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  • 1.
    Abdalla, Shireen
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Strömlind, Sandra
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Den ekonomiska lönsamheten att friköpa en tomträtt: En studie angående tomträtter i Gävle kommun2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Site-leasehold right is a form of access to a property. This means that the owner of the property, usually a municipality or the state, let a site-leaseholder use the property against an annual ground rent. A ground rent is determined by a site-leasehold agreement between the owner of the property and the site-leaseholder. The fixed ground rents are for a period of 10 or 20 years. Long periods of rents combined with a real estate market with rising prices means that the ground rent at a new period of ground rent can be increased considerably. The site-leaseholder may well choose to redeem their long lease. To buy the freehold of a site-leasehold means that the site-leaseholder acquires the property of the property owner and form a new single-family real estate.  The purpose of the study is to provide a better understanding and knowledge of the site lessee facing the decision to retain the site-leasehold or redeem it. The goal of the project is to provide knowledge about when the economic viability of redeeming a siteleasehold may be deemed attained. Another goal is based on the site-leaseholders perspectives consider to highlighting the underlying reasons why a single-family siteleasehold redeemed.   The study is limited to detached single-family site-leaseholds in three geographical areas in the municipality of Gävle. The economic viability of redeeming single-family site-leasehold examined from the site-leasehold executiver's decision to sell or retain the site-leasehold. To examine more closely why a site lessee chooses to redeem the siteleasehold conducted qualitative telephone interviews.  From the results based on the study, it can be concluded that it is likely to be economically justified to redeem a single-family site-leasehold on the price of acquiring the plot is equal to or less than the amount that symbolizes the breaking point of economic viability. Of the respondents surveyed for the study the single biggest reason for why a site lessee chooses to redeem his site-leasehold was because of the uncertainty arising from the developments around the ground rent.

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  • 2.
    Abdalmunim, Rand
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Effektivisering av bygglovsprocessen gällande ändring av kulturhistoriskt värdefull bebyggelse: En fallstudie av ett miljonprogramsområde-Nya Nordostprojektet i Gävle2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    En stor del av Sveriges bebyggelse har byggts mellan 1965 och 1974 eftersom det rådde stor bostadsbrist i Sverige. Regeringen beslutade att en miljon bostäder skulle uppföras under denna tid, det s.k. miljonprogrammet. Det byggdes bostäder i varierande former och storlekar för att bygga bort bostadsbristen. Storskaligheten och en stor grad av upprepning av identiska hus är kännetecken för miljonprogrammets bebyggelser. Nu är det dags att renovera dessa byggnader. I och med att dessa byggnader är av allmänt intresse då de speglar en del av Sveriges arkitekturhistoria ställer kommunerna vissa krav vid renovering av dem. Det kommunala företaget Gavlegårdarna i Gävle tar initiativ till att utveckla bygglovsprocessen för sådana bebyggelser. Detta görs för att reducera tiden för framställande av ett godkänt bygglov samt effektivisera och underlätta kommunikationen med kommunen under hela projektet. För att kunna bevara dessa byggnader i högsta möjliga mån har Gavlegårdarna utarbetat en effektiviseringsprocess genom att hyra in en extern bevarandeexpert för att fungera som en bro mellan företaget och kommunen samt för att kunna dela med sig av sina erfarenheter gällande bevarandet av det eventuella området. Dessutom har Gavlegårdarna låtit kommunen vara med från ett tidigt skede, d.v.s. redan från den första presentationen av förslaget. Därmed har kommunen fått vara med och medverka i förslaget, redan innan bygglovsansökan.

     

    Detta examensarbete tar upp konsekvenserna av de nya tillagda rutinerna och hur de har påverkat bygglovsansökningsprocessen för Nya Nordostprojektet. Genom att intervjua de inblandade aktörerna i det undersökta projektet har slutsatsen dragits att dessa rutiner har bidragit till att processen bedrivits mer effektivt jämfört med företagets tidigare projekt. Därutöver visar denna uppsats hur hyresgästerna har engagerat sig i det eventuella arbetet. Enkätundersökning har utförts för att kunna höra hyresgästernas åsikt.

     

    Det har visat sig att de nya rutinerna har effektiviserat tiden för bygglovsansöknings-processen. Tiden har förkortats jämförts med Gavlegårdarnas övriga projekt. Fördröjning i tid kostar företaget mer pengar. Dessutom har den förbättrade kommunikationen underlättat för båda parter att ta emot klagomål lättare och acceptera det. Det bidrar till att kommande problem kan lösas smidigare. Undersökningen har även visat att i projekt som Nya Nordost tas inte stor hänsyn till hyresgästernas åsikter, då byggherren redan är styrd från kommunen, vilket försvårar att flera kan vara med och välja. Ett annat resultat av denna undersökning var att de intervjuade personerna hade olika åsikter om bevarandet gällande Nordost. De flesta tyckte att Nordost ej var värt att bevara. Undersökningen visade även att hyresgästerna inte har engagerat sig lika mycket i bevarandet av gamla byggnader jämfört med att bo i ett modernare och nyrenoverat område.

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  • 3.
    Abdi, Joan
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences. Joan Abdi.
    Joel, Johansson
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    Georeferering av ortofoto med UAV: En jämförelsestudie mellan direkt och indirekt georeferering2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    UAV (Unmanned Aircraft Vehicle) has revolutionized the creation of orthophotos with its contribution to increased safety, lower costs and more effective ways when making orthophotos. The traditional aerial photogrammetry with airplanes and placement of flight signals has been the standard method for years. To fly with UAV instead of an airplane is cheaper and saves time, however, the placement and measurements of flight signals is still time consuming and therefore expensive. The company DJI has developed a new UAV called Phantom 4 RTK that supports satellite based technology for direct georeferercing.

    This study compared two different measuring methods when producing orthophotos with UAV: direct georeferencing with NRTK (Network Real Time Kinematic) and indirect georeferencing when using different number of Ground Control Points (GCP). The study was conducted at the University of Gävle over an area of eight hectares. An investigation of the deviation in plane and height resulted in acceptable units based on the guidelines that were followed in HMK – Ortofoto and the controls that were followed from SIS- TS 21144:2016.

    The RMS value in plane for the indirect georeferencing method is 0,0102 m. For the direct georeferencing method the RMS value in plane when using ground control points is between 0,0132 and 0,0148 m. At last the RMS value for the direct georeferencing method without ground control points is 0,0136m. The RMS value in height is between the intervals 0,008-0,025 m.

    The data presented in this study show that an accepted quality in the orthophotos can be acquired based on the RMS values in plane and height for every georeferencing that was tested. After accomplished controls and evaluation the results show that the different georeferencing methods doesn´t differantiate too much from each other based on their quality. However, the direct georeferencing method with ground control points is more effective from a time perspective.

    Phantom 4 RTK is new on the market and more research is necessary in order to understand the potential of this technology and its posibility to integrate into society. More research is recquired for the direct georeferencing method in order to evaluate the quality of orthophotos.

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  • 4.
    Abdi, Shorash
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Stedt, Fredrik
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Utvärdering av Leicas multistations och laserskanners mätosäkerheter2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Presently there is no standard for the evaluation of measurement uncertainties for terrestrial laser scanner (TLS) despite the fact that the instrument has been on the market and used for a long time. Since the manufacturer's specifications do not always correspond with reality, it is important to have knowledge about how well the instrument performs. Numerous studies over the past decade have applied different approaches to estimate the measurement uncertainties on various TLS.

    The purpose of this study was to evaluate and compare the measurement uncertainties of the TLS Leica ScanStation C10 with the multi station Leica Nova MS50 under two different weather conditions. The uncertainty was calculated using ISO 17123-5:2012, which is an international standard developed for acquiring measurement uncertainties of total stations, to investigate whether this standard could also be applicable for TLS. The survey, which took place outdoor at the University of Gävle, was carried out by scanning targets that were set up in a triangle formation from three stations. Both spheres and HDS-targets were scanned with the TLS while the MS50 only scanned spheres. The targets were scanned four times from each instrument setup. Cyclone was used to find the coordinates on the center of the targets which were used to calculate the uncertainties according to the ISO-standard. The results showed that the 3D-uncertainty of C10 with HDS-target and spheres were 2.9 mm and 3.5 mm during sunny conditions and 1.1 mm and 1.4 mm during cloudy conditions, respectively. In the case of the MS50, the uncertainty was 3.0 mm during sunny and 3.7 mm during cloudy conditions. MS50 demonstrated a higher 3D-uncertainty in both weather conditions due to high uncertainty in the vertical direction. In addition, a chi-two-test carried out on the TLS showed that the calculated uncertainty in plane and height did not significantly deviate from the manufacturer's specified uncertainty when using HDS-targets during cloudy conditions. Furthermore, it was found in the F-test that there was a significant difference in plane and height between two scans with the same instrument and target type in different weather conditions. MS50 did not show any significant difference at all. The results of this study showed that there will be a significantly lower uncertainty when scanning in cloudy conditions. Our conclusion is that it is possible to apply the standard to calculate the measurement uncertainties on TLS and ISO should consider using the same standard for TLS as the total station.

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    Utvärdering av Leicas multistations och laserskanners mätosäkerheter
  • 5.
    Abdul Hakim, Faisal
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Said, Shazad
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    En studie av småhusentreprenader: Varför går det fel?2021Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study was to investigate the single-family home construction industry and what problems arise. Furthermore, it was intended that this study would give the public a better idea of why conflicts arise between customers and contractors and how home suppliers work to counteract these problems.

    To achieve the purpose and get answers to the research questions, we used a qualitative research method in the form of semi-structured interviews. The reason why this interview technique was applied was to give respondents the freedom to talk openly about their experiences and views. The respondents interviewed were four representatives of house suppliers, three clients, a building inspector and an inspection manager.

    The results of the interviews showed that there was a common opinion among clients and house suppliers on certain issues, but then there were also opinions that differed. The study showed that customers experience the construction of detached houses as a slow and energy-intensive process. The problems that are common in detached house contracts are that there is a difference in language and knowledge between the involved parties. This results in a lack of communication which in turn can lead to various conflicts.

    Home suppliers are aware of the problems that exist in the industry and work continuously to develop solutions. One such solution is to place great emphasis on documentation and contracts because they are the ones that are legally binding. The conclusion of this study was that good communication results in fewer misunderstandings and conflicts. Conflicts, on the other hand, cannot be completely avoided, but will always arise due to human factors. 

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  • 6.
    Abu Sulaiman, Iyad
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science.
    Ibrahim, Miran
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science.
    Framställning av dränerande bärlager från bergtäkt2023Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Bearing layers are used in road and building constructions as underlying soil layers to provide stability and support to the top layer that takes up the load. A normal bearing layer contains different amounts of materials such as stone, gravel, and filler. That mixture of materials contains a large amount of filler to give the product tightness and stability. Draining bearing layers usually contain less filler than ordinary bearing layers, because their purpose is to improve the drainage properties and reduce the risk of damage due to water collection.This thesis work took place at NCC's quarries in Sälgsjö and Hammarby. At NCC's rock quarry, there already is a standard bearing layer with a grain size of 0/32 and a filler content of approximately 4–5%. In this degree project, a production process has been created to obtain a drain bearing layer where the filler content is reduced to approximately 2–3%. The requirement for a draining carrier layer is 2–3% filler content and this requirement has been followed in this production process. The draining bearing layer has been produced based on a standard product with the same grain size.There are practical limitations in how the operations work and what capabilities are required. Moisture in the material has also been a limitation. In this project, work is done with freshly crushed material, which has a relatively low moisture content (1–2%). A vibration-free screen like the function of the harp has been designed and built. Then the standard product was run through the harp at different gradients and the new product was analyzed in the lab to see what filler content was achieved. A simulation test was performed using a FEM design program called Digiroad at Chalmers University of Technology in Gothenburg.The results demonstrate that the utilization of the developed models of harp screens reduces the proportion of filler in the material. Additionally, the conducted harp screen analyses confirm that the designed harp screens are effective in transforming a standard bearing layer into a draining bearing layer, which helps to prevent water accumulation under roads or buildings and thus reduces the risk of damage and problems. The efficient production process for producing draining bearing layers can be of great importance to ensure a sustainable and safe infrastructure.

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  • 7.
    Abugessaisa, Imad
    et al.
    Department of Medicine, Karolinska Institutet.
    Östman, Anders
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Testing-SDI: E-government Prospective, Requirements, and Challenges2011In: International Journal of Public Information Systems, ISSN 1653-4360, Vol. 2011, no 1, p. 11-47Article in journal (Refereed)
    Abstract [en]

    Spatial Data Infrastructure denotes the collection of technologies, policies and institutional arrangements that facilitate the availability of and access to spatial information. During the last few years the development of spatial data infrastructure in Sweden has been influenced by two actions. The first was the European Directive in spatial data infrastructure namely Infrastructure for Spatial Information in Europe (INSPIRE), and the second action was the Swedish parliament's directive early in 2008 on e-Government. In a modern society, spatial data play major roles and have different applications such as information support during disaster prevention and management. These two milestones involving Geodata development have created huge demands and represent great challenges for researchers in the area of spatial data infrastructure. One of these challenges concerned the methodologies involved for testing proposed data specifications from INSPIRE. This paper addresses the above challenge and introduces a framework for testing Geodata. The testing of Geodata includes, the testing of the data specifications for different geographical themes and data structure, the performance testing of Opengeospatial Web Services (OWS) and the usability of Geoportals and services. The proposed methods were evaluated during a pilot test for a regional geoportal in Sweden, and the reported results in this paper show the feasibility and applicability of the methods used. The methods used assisted in the identification of the performance related defects and the bottleneck involved in relation to the response time, stress and load. The methods support the detection of different types of errors that occur during the testing time such as http error, timeout error, and socket error. During the pilot test of a geoportal, it was discovered that the response time was 30 seconds which is 6 times higher than the INSPIRE required time (Maximum 5 second), with 500 virtual users accessing the system and performing a specific task. A usability test was conducted which focused on the users' acceptance and the “think aloud” methods. The usability testing enabled the identification of user-interface related problems and the results were quantified to enable comparisons to be made with current results and those from the new test.

  • 8.
    Abushaqfa, Omar
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science.
    Bakero, Daniel
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science.
    Materials brandförmåga för mellanväggar2023Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nowadays, architects, designers and engineers pay a lot of attention to fire safety in buildings.Due to the high number of accidents, fire safety in construction is becoming increasinglyimportant.In order to use more fire-resistant material in the structure, attention was paid to the propertiesof the materials used. The material has begun to be evaluated for standard resistance and somestandard tests have been developed. Based on how long the material did not show anysignificant damage, these materials were evaluated and graded. This classification can beaccessed from Eurocodes (Svensk trä,2022).Timber was used in construction even before history was written. Since the ancient civilization,wood has been an important building material.Wood exhibits great resistance to fire due to its self-insulating property.When wood burns, it first chars to a certain depth. Then the outer charred layer acts as a barrierand suppresses the fire. This fire-extinguishing property in itself is the wood's self-insulatingproperty. (Swedish wood, 2021).Fire exposure usually occurs according to the standard fire curve that describes a fullydeveloped fire as defined in EN 1363-1. Building parts must withstand fire for a certain time,for example 60 minutes. With wooden constructions, it is possible to achieve high fire resistancewith the help of insulating material (EI). (Swedish wood, 2021).In the first part of the thesis, the properties of wood as a building material are discussed. INthe next part discusses the fire classes Br0, Br1, Br2 and Br3 for buildings. After that, the readercan learn about how a building can be divided into sections depending on its fire rating. Amaterial investigation will be done to be able to see the fire properties of certain materials thatwe will add to or remove from the wall such as extra plasterboard or insulation material withoutchanging the thickness of the wall to make them more fireproof and to be able to last longerwithout the fire spreads to the other spaces with the help of better material ability. (Swedishwood, 2021).This work also presents the theory behind wall fire sectioning in terms of materials and thevarious fire engineering solutions with some examples of calculations relating to the fireresistance of the materials, with references to the instructions in SS-EN 1995-1-2:2004/AC:2010. Finally, the results are analyzed and compared with different materials. Usingthe results of reactions of different types of materials and insulation, the fire resistance ofwooden walls can be discussed in more detail.Results show that gypsum boards combined with stone wool is the best choice of material forcreating fireproof partition walls. The results of our calculations show that double gypsumboards on each side with a thickness of 15 mm combined with stone wool with a thickness of95 mm provides fire resistance up to 109 minutes. Compared to a partition wall with a gypsumboard on each side without insulation, fire resistance is up to 48 minutes. This has beenemphasized with a study where the fire resistance has been investigated for walls, they havefound that double gypsum board combined with stone wool with the right conditions providesfire resistance up to 142 minutes. However, it is crucial for fire resistance to work that theinstallation is carried out correctly. All resulting screws must be placed correctly, there must beno holes on the gypsum boards and the number of gypsum boards and insulation thicknesstogether with the correct assembly provides better fire protection. This is based on the resultsthat have been obtained from articles, calculation during this work and from interviews withthe companies that work with requirements, manufacture and installation of fireproof partitionwalls. 

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  • 9.
    Ageborn, Elisabeth
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    Cardenström, Caroline
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    Acceptans hos närboende vid etablering av bygdeväg: En fallstudie av Sundsvall- och Timrå kommun2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the case of infrastructure projects, the authority should inform the nearby residents about what is happening in their area. Research shows that anchoring and trust are created when dialogues are applied in the planning process. These democratic processes are important to satisfy the interests of the public. The social aspect of a sustainable development is strengthened by allowing the public to participate in society's development, which in turn leads to greater equality. Changes create different reactions and communication has a significant role in the link between the public and authority, since information flows can contribute to less irritations and misunderstandings. An authority like the Swedish Traffic Authority not only has to deal with the public when establishing infrastructure projects, but also systems for planning processes, legislation, and financial frameworks. The purpose of this study is to investigate how the Traffic authority goes about giving out information to nearby residents in the planning process of new infrastructure and how the distribution of information affects the nearby residents' acceptance of the infrastructure project.

    A case study is carried out over two “2minus1” rural roads in Sundsvall and Timrå municipalities. For methods, questionnaires and interviews are used in studies, with the aim of collecting qualitative and quantitative data. Two methods are used to be able to verify results, as well as to get an overall picture of how the process works when establishing a “2minus1” road. Web-based questionnaires were sent to nearby residents at the two “2minus1” road, several interviews of nearby residents were conducted during site visits, and interviews were conducted with employees at the Swedish Traffic Authority who have expertise in establishing “2minus1” roads.

    The results of the interviews with the Swedish Traffic authority showed that there is no elaborate process for how they should distribute information to nearby residents when establishing a “2minus1” roads. This is because the “2minus1” roads are a new type of road and only a few of them have been established in Sweden. The results of the study indicate that information has a great importance for the acceptance of nearby residents. Acceptance is affected by when the information is distributed and whether the content of the information is adapted to the target group. By providing information on how the “2minus1” roads should be used and providing an understanding of the benefits of a “2minus1” roads, it contributes to greater acceptance by residents. Acceptance is a complex subject that can depend on many different factors. Acceptance is not only impact by information, but it can also depend on personal preferences.

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  • 10.
    Agebro, Andreas
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Datormodellering av en värmelagrande betongväggs inverkan på det termiska klimatet i ett växthus2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report describes the building of a computer model that makes it possible to simulate the thermal climate in a greenhouse. The computer model is built on the physical theory of heat exchange that occur in a greenhouse, such as radiation and convective heat exchange. The model also includes the heat storage that is active in a greenhouse.

    The computer model is used to simulate the thermal climate in a greenhouse under three periods, winter, spring and summer. It also investigates which effect a concrete wall has on the thermal climate in a greenhouse. The purpose of putting a concrete wall in the greenhouse model is to investigate the possibility to store heat during the day and then use this heat when the temperature drops during the night.

    The result from the simulations shows that a concrete wall levels the big difference in temperature that normally occurs under a day in a greenhouse. It also shows that heat is stored in the concrete wall and during the night the wall temperature is higher than both the outdoor temperature and the greenhouse temperature. This makes the wall a source of heat during this time.

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  • 11.
    Ahmad, Afaq
    et al.
    Department of Civil Engineering, University of Engineering and Technology, Taxila, Rawalpindi 46600, Pakistan.
    Bahrami, Alireza
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Alajarmeh, Omar
    Centre for Future Materials (CFM), School of Civil Engineering and Surveying, University of Southern Queensland, Toowoomba 4350, Australia.
    Chairman, Nida
    Department of Civil and Architectural Engineering, University of Westminster, London W1B 2HW, UK.
    Yaqub, Muhammad
    Department of Civil Engineering, University of Engineering and Technology, Taxila 47080, Pakistan.
    Investigation of Circular Hollow Concrete Columns Reinforced with GFRP Bars and Spirals2023In: Buildings, E-ISSN 2075-5309, Vol. 13, no 4, article id 1056Article in journal (Refereed)
    Abstract [en]

    Glass fiber-reinforced polymer (GFRP) reinforcements are useful alternatives to traditional steel bars in concrete structures, particularly in vertical structural elements such as columns, as they are less prone to corrosion, and impart increasing strength and endurance of buildings. There is limited research on the finite element analysis (FEA) of the structural behavior of hollow glass fiber-reinforced polymer reinforced concrete (GFRPRC) columns. The hollow portion can be used for the service duct and for reducing the self-weight of the members. Numerical analysis of the compressive response of circular hollow concrete columns reinforced with GFRP bars and spirals is performed in this study. This article aims to investigate the axial behavior of hollow GFRP concrete columns and compare it with that of solid steel reinforced concrete (RC) columns as well as hollow steel RC columns. The Abaqus software is used to construct finite element models. After calibration of modeling using an experimental test result as a control model, a parametric study is conducted. The columns with the same geometry, loading, and boundary conditions are analyzed in the parametric study. It is resulted that the hollow GFRP concrete columns provide a greater confinement effect than the solid steel RC columns. The average variation in the ultimate axial load-carrying capacities of the experimental results, from that of the FEA values, is noted to be only 3.87%, while the average difference in the corresponding deformations is 7.08%. Moreover, the hollow GFRP concrete columns possess greater axial load and deformation capacities compared with the solid steel RC columns.

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  • 12.
    Ahmed, Ali Mohamed
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Rashid, Obaidullah
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Optimering av flervåningsbyggnadsstruktur genom att ersätta bärande väggar med pelare och balkar2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I takt med att den globala befolkningen fortsätter att växa, ökar efterfrågan på nya bostadsbyggnader avsevärt. Samtidigt har behovet av bostäder och byggande vuxit över hela världenunder de senaste decennierna, vilket har lett till en ökad efterfrågan på byggmaterial. Betong ärdet viktigaste byggmaterialet för flervåningsbyggnader pga. sin hållfasthet, men det bidrarbetydligt till utsläppen av växthusgaser. För att minska koldioxidavtrycket och främja hållbarhet är det avgörande att minimera materialanvändning med moderna byggmetoder.Syftet med denna studie är att optimera flervåningsbyggnadsstrukturer genom att ersättabärande väggar med pelare och balkar. Studien använder en referensbyggnad belägen iSandvikens kommun och verktyget StruSoft FEM-Design. Studien genomförs i två steg.I steg 1 utförs modellering, design och analys av referensbyggnaden med bärande väggar(byggnad 1). I steg 2 genomförs en förändring av byggnadsstrukturen genom att ersätta debärande väggarna med pelare och balkar av armerad betong (byggnad 2). Samma procedurersom i steg 1 upprepas för den omkonstruerade strukturen. Resultaten jämförs medreferensbyggnaden med hänsyn till utnyttjandegrad, deformation, spänningar, reaktioner, viktoch stabilitet.Ersättningen av bärande väggar med bärande pelare och balkar av armerad betong har variteffektiv. Båda strukturerna uppfyller de nödvändiga kraven. Baserat på resultaten ärdeformationen 9 mm för byggnad 1 och 7 mm för byggnad 2, vilket indikerar att skillnaden ideformation mellan de två strukturerna inte är signifikant.Byggnad 1 har en maximal utnyttjandegrad på 87%, medan byggnad 2 har en högre maximalutnyttjandegrad på 99%. Detta innebär att byggnad 2 kan utnyttjas i större utsträckning änbyggnad 1. Reaktionskrafterna är 563,6 respektive 476,4 kN i båda byggnaderna, vilketindikerar att reaktionskrafterna i byggnad 2 är 15% lägre än i byggnad 1. Båda strukturerna ärstabila, men det finns en skillnad i byggnadernas totala vikt. Vikterna på byggnaderna är 4169respektive 3 143 ton. Resultatet indikerar att byggnadens totala vikt minskar med ca 25% vidanvändning av betongpelare och betongbalkar.

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  • 13.
    Ahmed, Mohamed
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Maxamed, Maxamed
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Modell för beslutsfattande avseende hållbar logistik: I både tjänsteföretag och tillverkningsföretag2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In any successful business, it is important to establish a dedicated management with the ability to make critical and sustainable decisions. Policy makers are a major and perhaps the biggest factor in a company and usually it is the managers who are also decision-makers. There are a number of aspects to keep in mind in order to make as appropriate decisions as possible, which can be anything from personality traits to how market analytic decision-maker is.

    The purpose of this thesis is to develop a model for decision-making on sustainable logistics, in both manufacturing companies and service companies in Sweden. Literature studies and interviews are conducted in order to answer the purpose. Through the literary study, significant factors can be found, for example crisis management and trust, prejudice and character traits.

    This work’s empirical material is based on interviews in four different organizations regarding their decision making and their approach to sustainable logistics. These organizations are both service and manufacturing companies, which gives the work a breadth and generalizability.

    The identified factors that are developed through the case studies include emotionality and rationality, trust, and transparency. Several factors in the literature are clearly consistent with the significant factors in the study result. The factors that both the service and manufacturing companies have in mind when making decisions regarding sustainable logistics are presented in the results. The conclusion of this study is a model that visualizes the factors one should keep in mind when making decisions regarding sustainable logistics. These factors are trust, supplier selection, unity, facts, transparency and empathy. Based on these factors, any company with a dedication and commitment to long-term decision-making processes can make wise and effective assessments.

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    Modell för beslutsfattande avseende hållbar logistik
  • 14.
    Ahmed Waqas, Hafiz
    et al.
    Ghulam Ishaq Khan Institute of Engineering Sciences and Technology, Topi, Swabi 23640, Pakistan.
    Bahrami, Alireza
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Sahil, Mehran
    Ghulam Ishaq Khan Institute of Engineering Sciences and Technology, Topi, Swabi 23640, Pakistan.
    Poshad Khan, Adil
    Ghulam Ishaq Khan Institute of Engineering Sciences and Technology, Topi, Swabi 23640, Pakistan.
    Ejaz, Ali
    National University of Science and Technology, Risalpur 23200, Pakistan.
    Shafique, Taimoor
    Ghulam Ishaq Khan Institute of Engineering Sciences and Technology, Topi, Swabi 23640, Pakistan.
    Tariq, Zain
    Ghulam Ishaq Khan Institute of Engineering Sciences and Technology, Topi, Swabi 23640, Pakistan.
    Ahmad, Sajeel
    Ghulam Ishaq Khan Institute of Engineering Sciences and Technology, Topi, Swabi 23640, Pakistan.
    Onuralp Özkılıç, Yasin
    Necmettin Erbakan University, Konya, Turkey.
    Performance Prediction of Hybrid Bamboo-Reinforced Concrete Beams Using Gene Expression Programming for Sustainable Construction2023In: Materials, ISSN 1996-1944, E-ISSN 1996-1944, Vol. 16, no 20, article id 6788Article in journal (Refereed)
    Abstract [en]

    The building and construction industry’s demand for steel reinforcement bars has increased with the rapid growth and development in the world. However, steel production contributes to harmful waste and emissions that cause environmental pollution and climate change-related problems. In light of sustainable construction practices, bamboo, a readily accessible and ecofriendly building material, is suggested as a viable replacement for steel rebars. Its cost-effectiveness, environmental sustainability, and considerable tensile strength make it a promising option. In this research, hybrid beams underwent analysis through the use of thoroughly validated finite element models (FEMs), wherein the replacement of steel rebars with bamboo was explored as an alternative reinforcement material. The standard-size beams were subjected to three-point loading using FEMs to study parameters such as the load–deflection response, energy absorption, maximum capacity, and failure patterns. Then, gene expression programming was integrated to aid in developing a more straightforward equation for predicting the flexural strength of bamboo-reinforced concrete beams. The results of this study support the conclusion that the replacement of a portion of flexural steel with bamboo in reinforced concrete beams does not have a detrimental impact on the overall load-bearing capacity and energy absorption of the structure. Furthermore, it may offer a cost-effective and feasible alternative. 

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  • 15.
    Ahnberg Åsenius, Elisabeth
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Land management, GIS.
    Lekmöjligheter och trafiksäkerhet för barn i stadsmiljöer: Fallstudie av centrala Falun2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Small children in the age around two to ten needs space to play and move around to be able to develop, and these needs should be considered in the spatial planning practice. Unfortunely there are signs that childrens need for places to play and move around have lost in priority in spatial planning practice in Sweden the last decades. For example research shows that childrens access to public places to play at in swedish citys is reduced. Also childrens possibilities to move around freely in swedish cities are continuously reduced due to increasing traffic. It has also been noted that fewer children walk or bicycle on there own to school and bicycling in the spare time has also been declining.   

    The aim of this study has been to exmine childrens possibilities to play and move around independently in urban environment. The study is restricted to a casestudy of the city-environment Falun-Centrum. That is an area of ca 2,5 km2 predefined by Falu kommun. It contains the city-center with shops, parks, roads, residential areas, kindergardens, schools etc. Information has been collected by a postal survey sent to guardians of 100 children (about 20 % of the total number in the area) that were older than one year and younger than eleven years during 2017 living in the casestudy-area.

    The results are based on 53 answers; 39 answers to the postal survey and 14 answers to additional interwievs over telephone. The answers show that in Falun-Centrum the respondents experience that their children have quite good access to places to play at in their vicinity. Field inventory of the places showed that many of the places were spacious enough to allow vast playing and had green and varied terrain, which is good. Though, the results about the safety aspects in traffic shows that there are a lot of traffic hazards that prevent the children to move around independently in the area.

    In summary it means that the children in general have good places to play at in there vicinity (although there are exeptions), but that they can not go there on their own due to traffic hazards. The lack of traffic safety also means that the conditions for them to go to, explore and get to know new places in their surroundings are severely limited. In the long run it limits the development of their geographichal imagination of their urban surroundings. It also limits their opporunities to meet, get to know and understand other persons in the city. In the long run it inhibits the urban social sustainability.

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  • 16.
    Aittamaa, Christina
    University of Gävle, Department of Technology and Built Environment.
    Inmätning av fastigheten Hållsta 2:3, Hudiksvall2007Student paper second term, 10 points / 15 hpStudent thesis
    Abstract [sv]

    Detta projekt har genomförts på mark- och mätningsavdelningen i Hudiksvalls kommun och projektets område är beläget norr om Hudiksvall, ca 6 km från centrala Hudiksvall vid norra infarten till E4:an.

    I området ligger en friskola, en gymnasieskola som heter ”Glada Hudik-skolan”. I skolans lokaler har det tidigare bedrivits hotellverksamhet i många år, f.d. Hammering Hotell. Hösten 2006 öppnade skolan sina portar och de räknar med att öka antalet elever varje läsår. I närheten av skolan finns den kända travbanan, Hagmyren.

    Syftet med arbetet var att göra en inmätning av fastigheten Hållsta 2:3, eftersom det inte fanns några inmätningar där tidigare. Stompunkter mättes in både i plan och höjd, därefter gjordes det detaljmätningar. Koordinatsystemet i plan i Hudiksvall är RTR10 2.5 gon V 0:- 15 och i höjd RH 70. Efter stom- och detaljmätningarna konstruerades en primärkarta i Geosecma som är ett kartprogram.

    I den här rapporten kommer mätmetoder, beräkningar, dokumentation och kartframställning att redovisas.

    Målet med projektet är att kommunen skall få nytta av inmätningarna i framtiden för olika projekteringar och att jag skall få mer erfarenhet av både mätning och kartframställning. Jag får även kunskaper om hur det går till på arbetsplatsen, tankegångar kring ett projekt och lärdomar av att arbeta självständigt.

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  • 17.
    Akander, Jan
    et al.
    University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för byggnadskvalitet.
    Stojanovic, Bojan
    University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för byggnadskvalitet.
    Hallberg, Daniel
    University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för byggnadskvalitet.
    Simulated Long-term Thermal Performance of a Building That Utilizes a Heat Pump System and Borehole2008In: Durability of Building Materials & Components 11: Globality and Locality in Durability / [ed] A. Nil Türkeri, Özkan Sengül, Istanbul, Turkey: Istanbul Technical University, 2008Conference paper (Refereed)
    Abstract [en]

    Over the last decades, installation and use of heat pumps has grown rapidly in Sweden, to the extent that these mainly or partly heat roughly 25 % of the heated floor space in single-family houses. A majority are ground coupled where the heat exchanger is a borehole of 60-220 m depth. As the heat pump system operates, heat extraction will in time reduce borehole temperatures, rendering lowered efficiency of the heat pump system thus directly affecting its economical and environmental aspects. Within the building sector, durability and life performance dynamics of energy systems is often not reflected upon. System performance and efficiency is assumed to be static over time, changing only due to different operation scenarios. This paper serves to quantify the long-term thermal performance degradation of a component, in this case the borehole, and how the degradation of this component affects performance-over-time of an entire system, in this case the heating system of the building. A dynamic thermal simulation model is used to assess the long-term thermal performance of the borehole. The building, which the heat pump serves, is assumed to be a typical Swedish house with normal energy consumption. Simulation results show that the depth of the borehole is of great importance to limit over-time temperature drops. The efficiency of the heat pump system is directly dependent of temperatures in the borehole. How the overall system performance is affected by component performance degradation, is highlighted.

  • 18.
    Aksoylu, Ceyhun
    et al.
    Konya Technical University, Konya 42250, Turkey.
    Özkılıç, Yasin Onuralp
    Necmettin Erbakan University, Konya, Turkey.
    Bahrami, Alireza
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Yıldızel, Sadık Alper
    Karamanoglu Mehmetbey University, Karaman, Turkey.
    Hakeem, Ibrahim Y.
    Najran University, Najran, Saudi Arabia.
    Özdöner, Nebi
    Necmettin Erbakan University, Konya 42000, Turkey.
    Başaran, Boğaçhan
    Amasya University, Amasya 05100, Turkey.
    Karalar, Memduh
    Zonguldak Bulent Ecevit University, Zonguldak, Turkey.
    Application of waste ceramic powder as a cement replacement in reinforced concrete beams toward sustainable usage in construction2023In: Case Studies in Construction Materials, E-ISSN 2214-5095, Vol. 19, article id e02444Article in journal (Refereed)
    Abstract [en]

    The main purpose of this study was to investigate the flexural behavior of reinforced concrete beams (RCBs) containing waste ceramic powder (CP) as partial replacement of cement. For this purpose, flexural tests were carried out using various amounts of mixing ratios. By determining the amount of CP utilized in the optimum ratios, it was aimed both to make predictions for design engineers and to show its beneficial effect on the environment by recycling the waste material. For this purpose, twelve specimens were produced and verified to monitor the flexural behavior. The longitudinal reinforcements percentage (0.77%, 1.21%, and 1.74%) and CP percentage (0%, 10%, 20%, and 30%) were chosen as the parameters. CP could be effectively used up to 10% of cement as a replacement material. Increasing the CP percentage by more than 10% could considerably reduce the load-carrying capacity, ductility, and stiffness of RCBs, specifically when the longitudinal reinforcements percentage was high. In other words, as CP increased from 0% to 30%, the load-carrying capacity decreased between 0.4% and 27.5% compared with RCBs with the longitudinal tension reinforcements of 2ϕ8 without CP. However, reductions of 5.5–39.8% and 2.15–39.5% in the load-carrying capacity occurred respectively compared with RCBs with the longitudinal tension reinforcements of 2ϕ10 and 2ϕ12 without CP. The achieved longitudinal reinforcements percentage was close to the balanced ratio, while more than 10% CP cannot be used without any precautions for mixtures.

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  • 19.
    Alaneme, George U
    et al.
    Department of Agricultural Engineering, Michael Okpara University of Agriculture, Umudike, P.M.B. 7267, Umuahia, 440109, Abia, Nigeria; Department of Civil Engineering, Kampala International University, Kampala, Uganda.
    Bahrami, Alireza
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Ibe Iro, Uzoma
    Department of Agricultural Engineering, Michael Okpara University of Agriculture, Umudike, P.M.B. 7267, Umuahia, 440109, Abia, Nigeria.
    Ganasen, Nakkeeran
    Department of Civil Engineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, 603203, India.
    Otu, Obeten N
    Department of Civil Engineering, University of Cross River State, Calabar, Nigeria.
    Udeala, Richard C
    Department of Agricultural Engineering, Michael Okpara University of Agriculture, Umudike, P.M.B. 7267, Umuahia, 440109, Abia, Nigeria.
    Ifebude, Blessing O
    Department of Agricultural Engineering, Michael Okpara University of Agriculture, Umudike, P.M.B. 7267, Umuahia, 440109, Abia, Nigeria.
    Onwusereaka, Emmanuel A
    Department of Agricultural Engineering, Michael Okpara University of Agriculture, Umudike, P.M.B. 7267, Umuahia, 440109, Abia, Nigeria.
    Numerical Analysis and Parametric Study on Multiple Degrees-of-Freedom Frames2023In: Civil Engineering Journal, ISSN 2676-6957, Vol. 9, no 7, p. 1709-1736Article in journal (Refereed)
    Abstract [en]

    The design of multiple degrees-of-freedom frames is critical in civil engineering, as these structures are commonly used in various applications such as buildings, bridges, and industrial structures. In this study, a six-degrees-of-freedom beam-column element stiffness matrix was formulated by superposition of beam and truss elements stiffness matrices and was adapted to statically analyze indeterminate frame structures. The development of a numerical model for the frame structures was achieved using the finite element method in the current study. Also, the investigation of the effects of various parameters such as frame geometries, material properties, and loading conditions was conducted on the internal forces developed in the frame structures. Three different parametric study cases that presented the frame structures with varying geometries and loading conditions were analyzed utilizing this matrix approach for the sake of emphasis and to evaluate the flexibility and adequacy of this formula to analyze the indeterminate frames using the MATLAB software. The analysis method comprised the derivation of the system displacements employing the relationships between the stiffness matrix and fixed end forces as the force vector and taking the attained displacements, which would be transformed to the local coordinates to obtain the member forces. The computed results from the element stiffness matrix approach were further statistically compared with the results achieved from the finite element software (SAP2000) applying the analysis of variance (ANOVA). The statistical results showed a P-value > 0.05, which indicated a good correlation between the compared results and adequate performance for the derived beam-column element matrix formula method. 

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  • 20.
    Albeman, William
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Lif, Emma
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Hur kan en gammal industribyggnad med kulturhistoriskt värde göras om till bostäder?: En fallstudie av lokstallarna i Bollnäs2022Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In Sweden there is a shortage of housing whilst old, abandoned industrial buildingstake up space on desirable land. These buildings generally do not live up to today’s standards regarding comfort and energy efficiency and are therefore not used today. If these buildings were to be renovated into housing, they could help remedy the housing shortage. However, many of these buildings are protected from distortion by law which makes renovation and remodeling difficult. The purpose of this work has been to provide solutions for how an old industrialbuilding with cultural-historical values can be remodeled into housing. The solutions consist of floor plans and drawings modeled in Autodesk Revit. The possibilities and difficulties with this kind of project as well as solutions to expected problems are also presented in the report. This work was executed as a case study on one of the old locomotive depots in Bollnäs. Since the building for this project is an old locomotive depot, it is positioned close to the railroad. Noise and ground pollution are therefore important to consider and demand certain measures, for example retaining walls, noise barriers and excavation of polluted soil. An energy simulation of the building was made using BV2 to determine the energy usage of the building. The walls, roof and slab were additionally insulated for the purpose of meeting the demands of energy efficiency and comfort defined by BBR 29. The insulation had to be internally constructed in order to avoid distortion of the facade. Additionally, all windows and doors had to be made energy efficient while remaining aesthetically preserved. Internal insulation is generally problematic due to problems with moisture. The solution to this problem was to insulate the walls with polyurethane foam and the slab with cellular plastic. In order to make the building energy efficient, the building should be heated using district heating in combination with photovoltaic panels. This building is well suited for solar panels due to the large, black metal sheet roof and shadow free placement. The study shows the complexity of refurbishing this type of building. The renovation is extensive, and the floor plans are characterized by compromises. It is possible to renovate the building without distorting it. A better alternative would be to use the building for other functions such as a store, restaurant or bar. 

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  • 21.
    Albuquerque, Daniel P.
    et al.
    Universidade de Lisboa.
    Sandberg, Mats
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Linden, P. F.
    University of Cambridge.
    Carrilho da Graça, Guilherme
    Universidade de Lisboa.
    Experimental and numerical investigation of pumping ventilation on the leeward side of a cubic building2020In: Building and Environment, ISSN 0360-1323, E-ISSN 1873-684X, Vol. 179, article id 106897Article in journal (Refereed)
    Abstract [en]

    Unstable interaction between shear layers that form in the wake of an isolated building exposed to wind can drive natural pumping ventilation in windward and leeward facing rooms with two or more horizontally separated openings. This paper presents an experimental and numerical study of pumping ventilation in a three-story cubic building with two leeward openings in its middle floor. Reduced-scaled measurements were performed in the University of Gävle atmospheric-boundary-layer wind tunnel. The ventilation mechanism was investigated using smoke visualization, hot wire anemometry and particle image velocimetry. Effective ventilation rates were obtained using a tracer gas decay method. Experimental results confirmed that pumping ventilation is a 3D oscillatory unstable phenomenon with periodic behavior over several oscillation cycles. Measured flowrates show a linear relation between the effective ventilation rate and window separation. The numerical simulations used two turbulence modeling approaches: unsteady Reynolds-averaged Navier-Stokes (URANS) and large eddy simulation (LES). Both URANS and LES could predict vortex shedding frequency with an error below 5%. LES showed a good agreement with the measured ventilation rates, with an error below 10%, while URANS underestimated ventilation rates by at least 40%. The ventilation efficiency, obtained by LES, ranged between 0.60 and 0.75 (for the case with larger window separation). The results show that LES may be a suitable simulation approach for pumping ventilation. In contrast, URANS cannot simulate pumping ventilation.

  • 22.
    Albuquerque, Daniel
    et al.
    Universidade de Lisboa, Portugal.
    Sandberg, Mats
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Linden, Paul
    University of Cambridge, UK.
    da Graca, Guilherme Carrilho
    Universidade de Lisboa, Portugal.
    LES simulation of oscillating natural ventilation driven by vortex shedding in isolated buildings2020In: Proceedings of Building Simulation 2019: 16th Conference of IBPSA / [ed] Corrado et al., IBPSA , 2020, p. 644-649, article id 11456Conference paper (Refereed)
    Abstract [en]

    A recently published study presented a new type of natural ventilation (NV) flow, named pumping ventilation. The oscilatory mechanism of vortex shedding that occurs at the wake region of an isolated building drives this new type of ventilation in rooms with two (or more) openings facing the leeward or windward side of an isolated building. This paper presents a validated Large Eddy Simulation (LES) study of oscillating/pumping NV in an isolated building using three different separations (s') between its two windows. LES is validated using an experimental database from measurements performed at the University of Gavle boundary layer wind tunnel (WT). The measurements use a cubic model with 0.45m side representing a three-story building at a 1/20 scale that allows the use of bottom-hung windows. LES results show a good agreement with the measured non-dimensional ventilation rates. A dimensionless analysis shows the dominant frequencies of the pumping flow, are close to the Strouhal frequency.

  • 23.
    Ali, Liaqat
    et al.
    Southern University of Science and Technology, Shenzhen, China.
    Isleem, Haytham F.
    Qujing Normal University, Qujing 655011, Yunnan, China.
    Bahrami, Alireza
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Jha, Ishan
    Indian Institute of Technology-BHU, Varanasi, Uttar Pradesh, India.
    Zou, Guang
    Southern University of Science and Technology, Shenzhen, China.
    Kumar, Rakesh
    National Institute of Technology Patna, India.
    Sadeq, Abdellatif M.
    Qatar University, Doha, Qatar.
    Jahami, Ali
    University of Balamand, Tripoli P.O. Box 100, Lebanon.
    Integrated behavioural analysis of FRP-confined circular columns using FEM and machine learning2024In: Composites Part C: Open Access, ISSN 2666-6820, Vol. 13, article id 100444Article in journal (Refereed)
    Abstract [en]

    This study investigates the structural behaviour of double-skin columns, introducing novel double-skin double filled tubular (DSDFT) columns, which utilise double steel tubes and concrete to enhance the load-carrying capacity and ductility beyond conventional double-skin hollow tubular (DSHT) columns, employing a combination of finite element model (FEM) and machine learning (ML) techniques. A total of 48 columns (DSHT+DSDFT) were created to examine the impact of various parameters, such as double steel tube configurations, thickness of fibre-reinforced polymer (FRP) layer, type of FRP material, and steel tube diameter, on the load-carrying capacity and ductility of the columns. The results were validated against the experimental findings to ensure their accuracy. Key findings highlight the advantages of the DSDFT configuration. Compared to the DSHT columns, the DSDFT columns exhibited remarkable 19.54 % to 101.21 % increases in the load-carrying capacity, demonstrating improved ductility and load-bearing capabilities. Thicker FRP layers enhanced the load-carrying capacity up to 15 %, however at the expense of the reduced axial strain. It was also observed that glass FRP wrapping displayed 25 % superior ultimate axial strain than aramid FRP wrapping. Four different ML models were assessed to predict the axial load-carrying capacity of the columns, with long short-term memory (LSTM) and bidirectional LSTM models emerging as superior choices indicating exceptional predictive capabilities. This interdisciplinary approach offers valuable insights into designing and optimising confined column systems. It sheds light on both double-tube and single-tube configurations, propelling advancements in structural engineering practices for new constructions and retrofitting. Further, it lays out a blueprint for maximising the performance of the confined columns under the axial compression.

  • 24.
    Ali, Remen
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Issa, Yaser
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Återanvändning av byggnadsmaterial: En fallstudie om Andersberg förskola i Gävle2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This work is about recycling of building materials. The aim of this work is to find out which building materials and equipment could be reused after the deconstruction of the Andersbergsgården preschool in Gävle, and to examine the profitability of these building materials and equipment if it is to be selectively demolished, stored and then reused.Both theory and conclusion were formulated through a literature study at the beginning of the work and contact with the involved companies. Research shows that 95% of building materials can be recycled. This percentage can be achieved if the building does not contain hazardous substances in the construction or it´s in bad condition.The study highlights some of the barriers to the wider use of reused materials. Examples of this are the verification of guarantees and qualities of the materials. It has been shown that the cost of traditional demolition generally is higher than the cost of selective demolition. What can be stored and reused are doors because these are in good condition.In the end, the conclusion is that all building materials in the Andersbergsgården preschool, with the exception of concrete and insulation, can be recycled. The reasons for this are that the concrete has had moisture problems and the insulation is too old to be recycled

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  • 25.
    Ali, Shara
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Khatibi, Farida
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Påbyggnad av våningsplan ovanför befintligt höghus: En fallstudie inom förtätning av storstäder2022Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Throughout Sweden, the cities expand due to increased population. The expansion causes housing shortage and the need for larger infrastructure especially in larger cities where the ground surface is more limited and restricted. These circumstances cause a dilemma as to whether the establishment of new infrastructure or new residential apartments should be prioritized, basically the establishment of new infrastructure vs. the establishment of new residential apartments.  

    A suggestion of a solution for this case is vertical building extension implying to build above an existing building without any utilization of the ground surface being required or needed. The empty space above an existing building, whether it is a high rise building or a single-family house, is being turned to advantage for expansion of the floor area. 

    This concept is an alternative to horizontal building extension. Unlike vertical building extension, it requires utilization of the ground surface and is therefore not suitable for this case.

    This thesis constitutes a case study covering the projecting phase in the building process of vertical building extension of storeys on existing high-rise buildings located in large cities such as Stockholm. Vertical building extension is presented as a solution for densification of large cities. There are several subjects which are investigated in the projecting phase. Architecture, urban planning, geotechnics, building construction and sustainability are a few of the subjects and these are specifically investigated in this case study. 

    The aim with this paper is through the mentioned investigation, to clarify why vertical building extension could be a solution for urban circumstances like housing shortage.

    This case study is based on qualitative research. Collection of scientific information has been done through both literature research and online research. 

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    fulltext
  • 26.
    Alikhani, Mohammad
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    A GIS-based crowdsourcing iPhone Application to Report Necessities, Civic Issues, and Public Events2011Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Civic issues in a society can be reported through a crowdsourcing web application. People can download the application on their smartphones and report the issues such as a pothole or broken streetlight. The report is submitted by taking a photo of the issue and additional information is entered. At first, the reports are submitted to a call center and after analyzing they will be transferred to organizations responsible for this type of events. In such a crowdsourcing project it is very vital to motivate people to participate in the project. The reports are supplied by users and without an acceptable number of users the application would be useless. In addition, having the exact location of a report is very helpful to facilitate the process of solving civic issues. Positioning with smartphones is not very accurate as they do not have strong and accurate GPSs. Therefore, there is a need to improve the accuracy of the positioning process and consequently accuracy of the spatial data. The aim of this thesis is to investigate how to employ GIS to help reporting civic issues and how to design an interesting client interface for such an application, in order to motivate user to download and use it. The goal is also to find out shortcomings and weaknesses of the positioning with smartphones and find a way to improve its accuracy.Some of successful similar applications’ structures and their interfaces were reviewed. In addition, a survey among existing users of crowdsourcing applications has been done in order to find out how to design the application to be interesting for users. Furthermore, some techniques and methods were chosen in order to improve the GPS accuracy especially in the places with a low GPS signal strength. These methods exploit WLAN and some of embedded features in a smartphone such as microphone, camera, accelerometer, gyroscope to improve the positioning accuracy. In the end, along reporting civic issues the user is able to report and get information about cheap and appropriate necessities and public events in different geographical areas through a map-based application. Furthermore, he or she is benefited by some location-based services such as online-food or taxi. The client application’s interface was designed for iPhone.This GIS-based mobile application would be an appropriate alternative for the old reporting methods like phone call or mail. Nevertheless, reporting civic issues itself, cannot be necessarily a strong motivation to attract the user to download and use the application. Therefore, desired feedbacks of the crowd need to be found out in order to encourage them to spend their time for the application. User needs to get motivated to use the application and considered additional parts can be very helpful to reach this aim.

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    fulltext
  • 27.
    Aljaberi, Saif
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science.
    Majeed, Aram
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science.
    Energisimulering i modulhus: Fallstudie för uppskattning av energiprestanda och därefter energieffektivisera enligt passivhusstandaren2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

    The Building sector is today an important sector in our society, which means that more people move from the urban area to the big cities, which in turn increases building production. The building and service sector is the largest energy waste in Sweden and internationally, which is about 40% of Sweden's total energy use and 60% of that energy goes to heating. The EU Directive Energy Performance of Buildings Directive (EPBD), implemented the concept of near zero-energy houses, which comes into full force in 2020, which means that all newly-built buildings must be energy-efficient with better energy performance than todays buildings. This is in connection with the need of houses/buildings and rental costs continuing to increase. For this reason, Ljusbo Hyreshus AB has invented a solution that includes both climatesmart rental apartments and cheap rental costs, which has attracted more than 20 communes (kommuner in Sweden) to offer land for these apartments. The purpose of this thesis is to find out the energy performance of one of Ljusbo Hyreshus AB's prototype module houses. Furthermore, improvement proposals would be developed to make the module house more energy efficient. The prototype house consisted of a single-storey modularhouse that stay in Söderhamn, which has been chosen in this thesis for further investigations. The house had a total area of 45 m2 and consisted of 3 rooms and kitchen. In this case study, the energy performance has been developed using analysis methods in the form of hand calculations and the energy signature method. Subsequently, the result of the analysis would be validated and would form the basis for later identification of various energy efficiency measures that contributed to the reduction of energy performance in the house and thereby achieved the passive house standard. The result shows that the modularhouse does not fullfil BBR's requirements at present, because the house misses important components which is important for energy performance. For this reason, improvement proposals, specifically regarding the climate shell, on energy efficiency measures have been developed in this report. With the help of these energy efficiency measures, which mainly consist of additional insulation and energy-efficient windows and with an energy-efficient ventilation system with heat recovery (FTX) and an installed air-water heat pump, the passive house standard has been possible to achieve. Future measures, such as the installation of solar cells, have also been examined in the report. This is due to converting the building from a passive house to a plus energy house.

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    Energisimulering i modulhus
  • 28.
    Almberg, Stina
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development.
    Michel, Gabriella
    University of Gävle, Faculty of Engineering and Sustainable Development.
    Analys av energianvändningen i kvarteren Carolina och Jenny: en fallstudie2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    An energy study has been performed on two blocks in an area called Gävle Strand. The buildings are owned by a tenant-owner’s association called brf Carolina and were built by the company Skanska 2008. The builder as well as brf Carolina are pussled by the fact that electricity use is higher than expected while heating is less. Skanska is also very interested in finding out how much heat recovery from stale exhaust air through a geo-thermal heat pump is contributing to the general heating requirement and energy balance in four out of the ten buildings located on the properties.

    To find possible answers to the higher electricity use a literature survey on user behaviour was conducted. Simulations were executed in the energy simulation program BV2 testing the efficiency of a mechanical ventilation system with fans dispatching the used stale air with heat recovery through the geo-thermal heat pump in comparison to a HRV-system. As BV2 can’t simulate heat pumps its impact was instead calculated manually and added to the result from BV2.

    The result show that there are significant differences in both water and electricity use between households. The mean value in brf Carolina is also higher for both water and electricity use than the typical pattern value most commonly used in energy simulations for new buildings. The simulations and calculations show that a HRV-system is practically equal to the system chosen for these buildings. The geo-thermal heat pump make a substantial contribution to the heating requirements but also increases the electricity use in comparison to the HRV-system.

    The buildings over all have a good energy performance. The chosen heat recovery system is working well. If the source for energy is also valued a HRV-system is still preferable since it requires less electricity.In regards to user behaviour the under floor heating installed in the bathrooms and operated by the occupants is very likely to have a substantial impact on the higher than average electricity use. There are however many other factors that could have an impact on energy use due to behaviour factors. This is also a factor when varations between households are viewed.

    Key words; energy, energy simulation, user behaviour

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    FULLTEXT01
  • 29.
    Almstedt, Åsa
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    Peterson, Niclas
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    Lägesosäkerhet vid nätverks-RTK-mätning med inbyggd lutningskompensator: en undersökning av Leica GS18 T2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A recently introduced GNSS instrument on the market is Leica GS18 T with tilt compensation, based on GNSS/Inertial Navigation Systems (INS) integration, with no need to centre the survey pole with the GNSS instrument over the target point being measured. Besides making surveying faster, the tilt compensation technique enables measuring of hidden points where the use of conventional GNSS measuring normally is not possible without more time-consuming methods. The instrument also has advanced GNSS signal tracking which makes surveying in challenging environments possible.

    In this study, the Leica GS18 T has on behalf of Lantmäteriet been tested through studying the measurement uncertainty in network RTK measurement with tilted survey pole in three different situations: with the survey pole tilted in various degrees in both favourable and challenging survey environments; with tilt towards north, east, south and west to test if the tilt direction would affect the result; and for surveying of building corners as a possible field of application. In the latter case, the result was compared with what can be achieved with the conventional hidden point method using intersection of distances. The analysis of the measurement uncertainty was based on calculations of standard uncertainty, RMS (Root Mean Square) and mean deviation.

    The measurement uncertainty from the first part of the test was on cm-level horizontally, both in favourable and challenging survey environments, and in height on mm-level in favourable survey environment and on cm-level in challenging survey environment. Further, the results indicate that the tilt direction affects measurement uncertainty. The reason for this is not clarified and needs further investigation. The measurements of building corners resulted in a mean deviation of approximately 12 mm when the survey pole was tilted 30°. The hidden point method using intersection of distances generally resulted in lower mean deviation, even though the difference is relatively small (4 mm at best). To summarize, Leica GS18 T seems to be well suited for measuring with tilt in detailed surveying, at least if the requirements of position uncertainty is on cm-level.

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    fulltext
  • 30.
    Al-Mulla, Tiba
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Jämförelsestudier mellan olika typer av korslimmat träbjälklag:: Undersökning av konsekvenser vid ändring från betong- till korslimmat trä- bjälklag i ett flervåningshus2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Timber is one of the most common materials that had been use for a long time. The need for new buildings will affect the climate negatively, that is why it’s necessarily to find new ways to build quickly and sustainably. Cross-laminated timber (CLT) product came in the 1990- century. The material was developed to be used in high residential wood constructions buildings.

    The material considered to have good properties compared with other types of wood material, some of the studies showed the possibilities of building high residential with the CLT material. Such high rises buildings work best when CLT wood constructions combined with other materials, which called, Composite constructions.

    Case study preformed theoretically in Fullriggaren building in Alderholmen in Gävle city, the building have 14 floors and about 40 m high. With the purpose of trying to investigate the consequences that occur when the concrete floor slabs were replaces  with CLT wood floor slabs, taking into account the rules and standards for fire safety, acoustics, oscillations and vibrations. In order to achieve this and to determine the most suitable alternatives, the different types of CLT-wood floor slabs was compared.

    The building studied in its design and execution, and a simpler model created in Revit 2018. The challenge was that the building has a long span of maximum 10 m. The different types of CLT floor slabs which compared in the study was, CLT timber joist slaps, flat floor slab and CLT wood floor slabs in combination with steel hat beams and other beam steel types. Each type of floor slabs had its advantages and disadvantages, but the results and studies showed that timber and concrete composite floor slab combined with steel hat beams are the best possible options for the construction in Fullriggaren building, where the floor slab height is the shortest compared to other CLT wood floor types. With the chosen floor slab, the problem of vibration and oscillations will minimize. When using such a floor slab, the building height will increase, which means in this case, removing an entire floor from the building.

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    fulltext
  • 31.
    Al-Sabti, Rita
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science.
    Fransson, Josefin
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science.
    Missfärgat dricksvatten i Sandvikens kommun: En studie med avseende på järn och mangan2021Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Drinking water is a cornerstone to a prosperous society. The quality of drinking water is affected by the type of raw-water sources and how drinking water treatment is carried out in a drinking water treatment plant. If the quality of the drinking water deteriorates, it may indicate that the drinking water treatment is not optimal or that the quality of raw-water sources has changed.The municipality of Sandviken in Sweden has had recurring problems with brown and black discolorations of the drinking water. Brown and black discolorations can be caused by oxidation of iron and manganese in the drinking water distribution system. The oxidation of manganese leads to the formation of manganese dioxide that can accelerate the corrosion processes of cast iron pipes. The Swedish Food Agency has set a limit value for the concentration of iron and manganese in drinking water to prevent the formation of precipitates in the drinking water distribution system. The aim of the study is to investigate whether the discolorations are due to high levels of iron and manganese in the drinking water. Water samples were collected to practically and statistically analyse the concentrations of iron, manganese and the formation of manganese dioxide. The statistical analysis showed that the levels of manganese were at their highest closest to the drinking water treatment plant. No other statistical correlations have been established. The analysis of manganese showed that 20 out of 31 water samples were above the limit value. The limit value for manganese was already exceeded at the drinking water treatment plant. The analysis of iron showed that 2 out of 24 water samples were above the limit value. Results also showed the presence of manganese-oxidizing microorganisms in the drinking water distribution system. Manganese is emitted from the drinking water plant and favors microorganisms as well as increases the formation of manganese dioxide, which may cause corrosion on cast iron pipes. Thus, the composition of the drinking water can affect or accelerate corrosion in the drinking water distribution system.Theoretically, the discolorations that have been experienced by the users may be due to a high concentration of manganese. However, it cannot be excluded that discolorations may be caused by other factors as the result did not provide a statistical relationship between discoloration and the concentration of iron and manganese. Further studies are required to determine all the causes behind discoloured drinking water. The problem of the concentrations of manganese should be solved, whether or not it is the main cause of the water discoloration. The concentrations of iron and manganese are likely to increase in the raw water due to climate change. If the drinking water plant continues to mix surface and groundwater, the problem can be solved by installing a static mixer and introducing a separation step for iron and manganese. When choosing a biological separation method, microorganisms from the drinking water distribution system can be used.

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    Missfärgat dricksvatten i Sandvikens kommun
  • 32.
    Al-Saour Rafie, Mais
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Farhad, Tafan
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Tillgänglighet och användbarhet i nybyggnation: En fallstudie - Bostadslägenheter på Gävle Strand Etapp2 - Gavlegårdarna2014Independent thesis Basic level (university diploma), 180 HE creditsStudent thesis
    Abstract [en]

    Human beings are always considered to be the starting point for various construction projects; their needs and interests should always be the center of each successful design. At the same time, considerations should be given to activities and surrounding environment to ensure that buildings can be both accessible and usable.

    The accessibility and usability requirements for constructions were introduced in 1977 by the National Housing Board and have evolved since then. The requirements are still developing to achieve homes that are accessible and useable, especially for people with disabilities. They have also been tightened in particular concerning the design of new construction and alteration of buildings.

    Gavlegårdarna have, in 2012, built new residential apartments with high accessibility standards. The apartments in Gävle Strand, Stage 2 are located in an area next to the sea and offer new opportunities for a modern way of living. Considering the new residential area of Gävle Strand, this case study focuses on the accessibility standards concerning three categories of disabilities: limited mobility, limited vision and limited hearing. The case study examines three selected apartments with different living area. The purpose of the case study is to assess the accessibility and usability of the apartments. This is done through an inventory using a wheelchair, taking a walking tour while blindfolded and using a cane. Before the assessment of the apartments' requirements, an inventory list of respective apartments was prepared. The list is based on regulations, laws and recommendations from Building Regulations and Swedish Standard.

    The results of the case study categorize the apartments in two levels: normal- and high level accessibility. Spaces and details that are considered to have high accessibility have externally contrast markings including the entrances and stairways. Inside, the apartments are well planned for enhanced usability and there are spacious areas where a wheelchair can move without any difficulty.

    The conclusion shows that all apartments meet the requirements at normal level which is the minimum level of accessibility and usability. Despite the general assessment of the apartments’ well-planned design, the study finds flaws in the form of a cramped bathrooms and high thresholds to the balcony doors. Finally, in order to achieve high availability the case study presents improvements and measures that need to be changed to the presented deficiencies.

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    Tillgänglighet och användbarhet i nybyggnation
  • 33.
    Altabba, Abdulrahman
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Karlsson, Lina
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    A framework for implementing the VMI model in an MRO partnership2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Purpose - The purpose of this paper is to investigate the feasibility of implementing the Vendor Managed Inventory (VMI) model in an MRO (maintenance, repair, and operations) partnership, and highlight its potential economic, environmental, and organizational benefits, as well as limitations.

    Approach - First, a comprehensive literature review was conducted on fields relevant to VMI. Second, empirical data was gathered from a single exploratory case study with Momentum Industrial, and its customer Stora Enso. Semi-structured interviews were used to gather data from the case companies.

    Findings - Results suggest that VMI results in benefits for the supply chain in general, such as reduced administration and inventory costs, improved service levels, reduced information distortion, and improved relationship among partners. For the particular case of VMI in an MRO partnership, improved service levels can be obtained by a reduced risk of production downtime for the customer. Moreover, the implementation of VMI has potential environmental benefits, such as reduced paper use, and higher transportation fill rate. Limitations of implementing VMI include the difficulty in system integration, and information sharing. Trust could be a potential issue that limits information sharing amongst supply chain partners. Moreover, the difference in organizational cultures and policies of partners should be taken into consideration.

    Limitations - The study is limited to opinions from one MRO customer in the paper and packaging industry. Even though the questions asked to informants in Momentum and Stora Enso tackled benefits to MRO customers in general, a broader image could have been achieved by interviewing customers from different industries. Moreover, the case companies do not currently adopt VMI in their partnership, so the case study results are based on what they think would be the potential benefits and limitations of implementing VMI in an MRO partnership.

    Practical Implications - This paper can serve as a guideline for logistics managers who are considering VMI in an MRO partnership specifically, as it provides them with the benefits and limitations associated with VMI. More generally, any company considering VMI can also benefit from the theoretical framework presented.

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    Altabba, A. & Karlsson, L (2016)
  • 34.
    Aminzoui, Abla
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering.
    Vikten av kommunikation med inköpsavdelning: En studie ur medarbetarperpektiv i en fastighetsbolag2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purchasing function has become a strategic position for most companies. Activity in an organization cannot be performed without the presence of the information, which means that communication is important for being able to perform a task or activity. Communication related to the purchasing process has been investigated at Gavlegårdarna, a real estate company located in Gävle. In this work, Gavlegårdarna wanted to examine whether there is an opportunity to improve communication and investigate factors that lead to a lack of communication. The purpose of this study was to get a general image and increase understanding of factors that affect communication. The study is based on a case study, where one interview took place in the purchasing department and a questionnaire sent out to people who work daily with purchasing function.

    Download full text (pdf)
    Examensarbete
  • 35.
    Amiot, Victor
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Torung, Rikard
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Oliksidig krympning i betong2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Concrete is one of the most commonly used building materials in foundation construction. Concrete is highly resistant to external stresses and hence makes it a very useful material in many different situations. However, there are problems that can arise with the use of concrete. One of the more common is cracking. There are several reasons why this might occur, for example, external impact, creep and moist-related movements. The concrete slab is one of the elements that often encounter this problem. Since concrete slabs are frequently used as foundation, it is of great interest to find solutions for this matter. In order to do that, the causes are needed to be specified more clearly. This study investigated experimentally how a concrete slab reacts when differences in humidity exposing the top and bottom after curing period, and if this may contribute to sufficient deformation to cause cracking. Six specimens were made and observed where three where exposed to a moisture content of 100% on the bottom. The remaining three samples have been placed in dry conditions in order to make a comparison possible. A relative humidity of 25% was measured in the surrounding air. The experiment showed clear differences in deformation between the two situations. The samples exposed to differential humidity exhibited sufficient stresses to cause cracking seen from the moment that occurred in the concrete. This shows that different prevailing humidity on the top and bottom of a slab can create sufficient stress to cause cracking.

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    Oliksidig krympning i betong
  • 36.
    Andersson, Christine
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Linderdahl, Sofia
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Ett förslag till arbetsmiljöplan för underhållsarbete inom bygg: en förenkling av rutiner för arbetsmiljöarbetet2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    According to the Swedish Work Environment Authority (Arbetsmiljöverket), accidents among construction workers occur twice as often as other workers. In 2015 the construction industry had over three thousand work accidents resulting in sick leave, which corresponded to eleven percent of Swedens total reported work accidents with sick leave. Considering what a worker in the building and construction industry expose themselves to in their daily work, it is obvious that focus must be towards safety.

    This study has been carried out on the building department for maintenance work at BillerudKorsnäs Gävle Bruk. At the company, there is a need for improving the establishment of safety and health plans within the existing working environment work. The aim and objective of the study is to create a draft template for the safety and health plan that is user friendly and includes the 13 works with special risks according to AFS 1999:3. Hopefully the template will contribute to a simplification of existing procedures in the construction working environment planning, lead to increased safety on site and fewer work accidents.

    To receive a better understanding of the viewpoint of BillerudKorsnäs Gävle Bruks construction workers regarding working environment and risks on site, semi-structured interviews were conducted and together with statistics on accidents and incidents, served as the studies results. In addition, a literature review has been conducted to provide an overview of previous studies in the field.

    The importance in carrying out risk assessments has been confirmed through interviews and becomes more evident as the conditions in the daily construction work varies in large proportion. Every work situation and risk is unique, therefore a risk assessment can not only consist of the 13 works with special risks. The interviews have confirmed the need for a simplification and improvement in the process of establishing a safety and health plan. A template for the safety and health plan should include how the work environment shall be conducted such as general information about the work and a risk assessment.

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    Examensarbete 2016 Sofia och Christine
  • 37.
    Andersson, Daniel
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Land management, GIS.
    Färdigställande av Sveriges digitala förrättningsarkiv: Effekter av skanning av äldre gällande förrättningsakter2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When the Swedish Mapping, Cadastral and Land Registration Authority, Lantmäteriet, first digitised their archived cadastral procedures into the digital archive Arken, the aim was to create a national digital archive for cadastral procedures. Lantmäteriet now have their cadastral procedures digitised in Arken. Some municipalities still have their older analogue cadastral procedures from 1972 and before archived in the office of their local authority. For the cadastral procedure, this means the land surveyor is bound to contact the local authority to reach all information needed for the procedure.

    A digitisation of the remaining older cadastral procedures may improve their availability and make todays cadastral procedure more effective and manageable for Lantmäteriet. This also applies to other users of these older archived documents. This dissertation aims to answer the following questions: 1) How may cadastral procedures become more effective and 2) become more legally certain through a digitisation of the analogue archives? 3) Which impact may a digitisation of these older archives have on the real property market and the Swedish municipalities? The research questions were answered through inventory of cadastral procedures and personal interviews with local authorities and other actors, experienced of or influenced by these matters. The inventory helped answering the amount of work remaining in digitising these archives. The interviews answered which impact a digitisation of the material would have on different users of the information. Interviews were also used together to investigate both the legal certainty of cadastral procedures and the quality of the Swedish land registry.

    The result of the dissertation shows which impact a digitisation would have on different users of the information. The most common effect of digitisation was effectiveness in different aspects, such as timesaving and cost-effectiveness along with legal certainty. Conclusions from the dissertation are: all interviewed users of the older cadastral procedures are positive to a digitisation of the material. More effort in time and finance from the different Swedish local authorities and Lantmäteriet is needed and strongly recommended.

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    fulltext
  • 38.
    Andersson, Elias
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    Dokumentation av en trafikolycka med handhållen laserskanning och UAS-fotogrammetri: En utvärdering av punktmolnens lägesosäkerhet och visuella kvalitet2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the event of a traffic accident, it is often important to restore the site to its normal condition as fast as possible. Occasionally, the accident scene must be documented so that the cause of the accident can be investigated at a later stage. Traditionally, this work has been performed by taking pictures of the site and measuring different distances. Lately, terrestrial laser scanning has also become a reliable alternative. With that said, it is possible that photogrammetry and other types of laser scanning also could be utilized to achieve similar results.   

    The aim of this study is to investigate how handheld laser scanning and UAS photogrammetry can be used to document a traffic accident. This is achieved by examining the positional uncertainty and visual quality of the point clouds. Moreover, the advantages and disadvantages of each method are explored, for instance in terms of time consumption and costs, in order to finally come to a conclusion of which method is best suited for documenting a traffic accident.

    A traffic accident with two involved cars was staged and initially laser scanned with the handheld laser scanner Leica BLK2GO. Thereafter, pictures were collected with the unmanned aerial vehicle Leica Aibot followed by the creation of a reference point cloud with the terrestrial laser scanner Leica C10. By comparing the coordinates of control points in the reference point cloud with the coordinates of the corresponding control points in the two other point clouds, their positional uncertainty could be determined.

    The results of the study show that both the point cloud produced by the handheld laser scanner and UAS photogrammetry have a positional uncertainty (standard uncertainty) of 0.019 m. Both methods are applicable for documenting a traffic accident but compared to terrestrial laser scanning, the point clouds are deficient in different ways. BLK2GO produces a relatively dark point cloud and dark objects are reproduced worse than lighter objects. In the point cloud produced by Leica Aibot, there were noticeable cavities in the bodies of the cars. Handheld laser scanning is a time-efficient method while UAS photogrammetry can be performed at a lower cost.

    In conclusion, it is not possible to arrive at an unambiguous conclusion with regards to which method that is best suited for documenting a traffic accident. The choice depends on the prevailing circumstances at the accident scene.

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    fulltext
  • 39.
    Andersson, Elisabeth
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Maria, Reineck
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Betydande faktorer för effektiva specialtransporter2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    To be competitive in the market, companies need to find and use available resources for improvements. Transport is a source to cost-effective and customer accessible logistics system. Both internal and externals transports are important to focus on when processes are optimized in order to obtain lower costs. The main logistics cost in many companies constitutes of transports.

     

    This case study has been conducted in an industrial company. This study intends to make the transports more effective, through better customer service and reduced costs. The transports that have been studied are not directly linked to the production. When a transport is needed an order is made by telephone.

     

    The purpose of the study is to identify significant factors for effective special transports. The factors form a foundation for recommendations to the case company in the future work to have more effective special transports. To answer the purpose literature studies, observations, data analysis, interviews and benchmarking have been carried out. Some significant factors for effective special transports are information, effective logistics and standardization. Some identified waste in the case company is lack of communication and information and the utilization of resources. The significant factors have a correspondence with the identified waste.

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  • 40.
    Andersson, Harald
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    An Investigation Concerning Optimal Design of Confluent Jet Ventilation with Variable Air VolumeManuscript (preprint) (Other academic)
  • 41.
    Andersson, Jacob
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Land management, GIS.
    Norbäck, Markus
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Land management, GIS.
    Lokalisering av nya bostadsområden i översiktlig planering: En rumslig multikriterieanalys över Gävle2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Urbanization combined with toxic emissions from motor traffic calls forhigher demands when house planning in cities. The purpose of this study is toincrease understanding about how to apply multi criteria analyses whenmaster planning to contribute to a more sustainable society. A more effectivehouse planning connected to existing societal functions might add to the usageof more sustainable transportation alternatives rather than that of cars.

    Using the input from interviews with representatives from both the privateand the public sector, a number of criterias have been developed for theanalysis. Considering existing societal functions, this study was intended toidentify new areas for housing development using a multi criterial analysis.This might contribute to more sustainable transportation because of thedistance to the societal functions. In addition to this, the intention extended tothe investigation of how political interests differs from one another, using aranking system based on the developed criterias.

    The results show that representatives from the two largest political parties in asmall town in Sweden rank the criterias different when it comes to whatsocietal functions a new housing area should have in close proximity. On theother hand, the end results show that the areas chosen for housingdevelopment have similar qualities, in spite of varying housing politics amongthe politicians. This study might contribute to a more effective politicalhandling of business, since political differences does not ultimately showdifferences in where activities or objects should be placed.

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  • 42.
    Andersson, Jonas
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Hedlund, Patrik
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Undersökning om handhållna laserskannrar vid detaljmätning: En jämförelse mellan multistationen Leica Nova MS50 och den handhållna laserskannern FARO Freestyle X2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Terrestrial laser scanners (TLS) have been common in geodetic measurements for over 10 years. The technology is developing rapidly and specialized instruments are launched constantly. One type of these specialized TLS instruments are hand-held laser scanners. They are designed primarily to generate point clouds of spaces and small objects where the traditional tripod mounted laser scanner has difficulties to scan. When the hand-held laser scanners are relatively new, the research on the instruments is limited, and the lack of standardized control methods. With that in mind it is important to study the instruments. In this thesis the hand-held laser scanner FARO Freestyle X was investigated on how well the handheld laser scanning technology really is and what limitations the instruments have. This was done by comparing point clouds from FARO Freestyle X with reference point cloud generated by Leica's multi-station MS50. To study the instrument a number of parameters was investigated such as scanning distance, ease of use, time and performance. These parameters were considered to be sufficient basis for conclusions about the instrument's advantages/disadvantages and limitations.

    The result of the point cloud comparison from the short distance showed deviations around 10 mm and then increase to few centimeters at longer distances. Volume limitation control showed no differences compared to the scanning from short distance. This means that moving the instrument does not affect the results significantly. The instrument's Achilles' heel is the noise that occurs when scanning from longer distances, about 30 mm deviations. Even the type of object affects the noise. The noise on the wall showed the greatest deviation while the noise on the table indicated the lowest results. The repeatability showed good results visually and had similar deviations. The instrument has a good ability to recreate objects when the resolution test demonstrates good performance. Main advantage of the instrument is its effective documentation of smaller objects, but also some larger areas where the uncertainty of centimeter-level is required. The ease of use can be described as good and the colored point clouds takes visualization to a new level. The results of the study show that the hand-held laser scanners can, potentially, challenge the traditional laser scanner.

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    Undersökning om handhållna laserskannrar vid detaljmätning
  • 43.
    Andersson, Kjell
    et al.
    School for Forest Management, Faculty of Forest Sciences, Swedish University of Agriculture.
    Angelstam, Per
    School for Forest Management, Faculty of Forest Sciences, Swedish University of Agriculture / Department of Forestry and Wildlife Management, Inland Norway University of Applied Sciences.
    Brandt, S. Anders
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    Axelsson, Robert
    County Administrative Board Västmanland.
    Bax, Gerhard
    Limited GIS skills hamper spatial planning for green infrastructures in Sweden2022In: Geografiska Notiser, ISSN 0016-724X, Vol. 80, no 1, p. 16-35Article in journal (Other academic)
    Abstract [en]

    The term green infrastructure captures the need to conserve biodiversity and to sustain landscapes’ different ecosystem services. Maintaining green infrastructures through protected areas, management and landscape restoration requires knowledge in geography, spatial data about biophysical, anthropogenic and immaterial values, spatial comprehensive planning, and thus geographical information systems (GIS). To understand land use planning practices and planning education regarding GIS in Sweden we interviewed 43 planners and reviewed 20 planning education programmes. All planners used GIS to look at data but did not carry out spatial analyses of land covers. BSc programmes included more GIS than MSc programmes but very few taught analyses for spatial planning. As key spatial planning actors, municipalities’ barriers and bridges for improved GIS use for collaborative learning about green infrastructures are discussed. A concluding section presents examples of how GIS can support spatial planning for green infrastructures.

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    Limited-GIS-skills-hamper-spatial-planning
  • 44.
    Andersson, Leo
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences.
    Lägets betydelse för värdet på småhus och tomtmark vid skidanläggningar2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study is to find out if vicinity to alpine ski resorts affect the transfer prices of properties. The study should also describe and analyse whether the taxation level of singel-family house properties close to a ski resort should be managed through value area divisions. The study is written on behalf of Lantmäteriet.

    In Sweden, the land is divided into various large properties. Each property is unique, which means that they have different values. The most important factor for the property’s tax assessment value is its geographical location. If the property is far from the community with poor communications to a nearby city, it probably has a low property value. If the property on the other hand has good communications, close to shops, schools and access to municipal water and sewage, it probably has a higher property value. In order to investigate this, two local price surveys on two alpine ski resorts has been done, Björnrike and Lofsdalen in the municipality of Härjedalen. Data on sales has been collected for each area, which has been analysed and processed into the result of this study. Interviews have also been done in the study.

    The study shows that there is a connection between family-house properties that have ski-in/ski-out location and the tax assessment value. Properties that have this location are sold for a higher purchase price than the properties that do not have a ski-in/ski-out location. This study has only investigated how the ski-in/ski-out location affects the market value of properties in Björnrike and Lofsdalen. However, real estate agents from various alpine ski resorts in Sweden agree that the sales prices are higher for properties and condominiums with a ski-in/ski-out location.

    In Björnrike, the value difference is not significant enough in order to be managed through value area divisions. In Lofsdalen, on the other hand, family-house properties with ski-in/ski-out location should be handled with separate value area divisions. One suggestion that this study has resulted in, and which is reported in the discussion, is that family-house properties at alpine ski resorts could be handled in different location classes in relation to the ski slope and the ski lift. Based on the location class, the family-houses would then be assessed differently. The closer to the ski slope the property is located, the higher the location factor the property will have, which affects the tax assessment value.

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  • 45.
    Andersson, Linda
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Land management, GIS.
    Hedlund, Johanna
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Land management, GIS.
    Trivsam boendemiljö för studenter: En gestaltningsstudie utifrån studenters åsikter för ett trivsamt boende2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The physical environment is a very important component for human health.  A well-functioning site enables people to recreation and social life. People who spend a lot of time outdoor are also experiencing less stress. If people doesn’t give opportunity to influence the spatial planning process there is a risk of negative attitudes and discomfort. This can create a mental illness. This study deals with how students feel about their physical environment and how they want it to be designed. The study is aimed at students who live in one of the three different student areas in Gävle: Kungsbäck, Campus Sätra and Midgård. The study is based on three methods. These were: a questionnaire, an observation study, and a physical design study in 3D.

     

    The observations showed significant problems with the site design as only movement, who take into necessary but significant activity account. The observations showed a clear lack of both elective and social activities, both of which are important for a well-functioning place. The survey showed dissatisfaction about the site design among the students. Through this study, students were given an opportunity to share their wishes about the site's future design. The proposals were designed in 3D. Three different proposals were developed: a zero option, an economical option, and an expensive option. The zero option indicates a probable development of the area if no action takes place. The economical option indicates a solution that focus on economical sustainability. The expensive option has the highest costs both in construction and maintenance. The evaluation showed that the students liked the economical proposal option most.

     

    The result showed the importance of student participation in the planning process. Student comments through the survey and evaluation, indicated that: trees, venues, water, grass and lighting should be included in future planning frameworks for student housing.

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  • 46.
    Andersson, Martin
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Jonsson, Andreas
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Nyström, Niklas
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Insvällning av olimmade och limmade trädymlingar2019Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [en]

    Wood is a renewable material, unlike many other building materials. The amount of wood used in the construction industry can be increased by using wooden dowels as a substitute for screws and nails. Screws and nails are made of metals, which are non-renewable materials. The manufacturing process of metal-based materials is more energy consuming than it is for wooden materials and therefore it has a greater impact on our global environment.The purpose of this study was to investigate the adhesion capacity of wooden dowel-joints, non-glued and glued made out of beech and pine. The attachment of the non-glued wooden dowels was achieved by swelling of the wood. Swelling was achieved by first drying the wooden dowels in an oven and then letting them acclimatize with the surrounding materials and the relative air humidity. The adhesion capacity of the wooden dowels should be able to compete with the withdrawal strength of nails to be practically useful.Tensile strength tests have been carried out in the laboratory in house 45 at the University of Gavle to determine the adhesion capacity of wooden dowel-joints. The tensile strength tests were performed with a Shimadzu AG-X machine. The results of the tests have been compared with the theoretical withdrawal strength for nails. Characteristic strength values have also been calculated from the tensile strength test results for the wooden dowels.The results of the study shows that only the glued wooden dowels can compete with the withdrawal strength of nails. Glued wooden dowels can therefore be a substitute for screws and nails. The calculated characteristic values for glued beech-dowels and glued pine-dowels are 5,2 kN respectively 4,3 kN.

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    Insvällning av olimmade och limmade trädymlinga r
  • 47.
    Andersson, Mattias
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Stenberg, Catarina
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Effektivisering av interna transportsystem: Utformning av IT-stöd för fallföretag2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Att hantera den interna logistiken när marknaden är volatil och rörlig kan vara svårt. När avdelningar på företag inte kommunicerar eller delar information med varandra gör det att bistående företagsfunktioner, som interna transporter, får svårt att planera sina processer gentemot produktionsfabriker och marknaden, vilket kan leda till resursslöseri. För att underlätta arbetet och planeringen för den interna logistiken krävs att rätt teknik och förhållningssätt finns.

    Detta arbete tar fram en metodik som undersöker vilka faktorer som finns för att effektivisera den interna logistiken, samt hur ett IT-stöd för effektivisering kan utformas. Fallstudien avgränsas till interna transportsystem för de produktionsfabriker där sidlastare och grensletruckar utför transporter.

    Genom fallstudien på företaget visade det sig att de bristfälliga områdena var integrering och samarbete, kommunikation samt standardiserat arbetssätt. Detta försvårar arbetet med den interna logistiken och gör att företagsfunktionerna inte är synkroniserade i arbetet. Den bristfälliga informationsdelningen om framtida beläggningar och prognoser gör att planeringen av interna transporter mot produktionsenheterna inte fungerar önskvärt.

    I den teoretiska referensramen framgår att faktorer som påverkar effektiviteten av internlogistik är IT-stöd, arbetssätt och rutiner, planering och kommunikation samt resursutnyttjande. IT-stöd är något som kan hjälpa företag inom de bristfälliga områdena och vara en start till att integrera ett företags processer för att förbättra kommunikationen och informationsdelningen, som i sin tur ger bättre förutsättningar för att planera bistående företagsfunktioner till ett bättre resursutnyttjande.

    Genom metodiken för att effektivisera den interna logistiken påbörjas ett första steg av ett IT-stöd genom att en EXCEL-modell skapas som ett underlag för planeringsprocessen av interna transporter på fallföretaget. EXCEL-modellen skapas genom sammanförandet av historiska data från transportavdelningen och produktionsfabrikerna. Metodiken kan vidare användas för framtida undersökningar för effektivisering av den interna logistiken på företag.

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  • 48.
    Andersson, Michael
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Jonsson, Axel
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Strorheter vid bedömning av energieffektivitet för byggnader: En fallstudie för indikator 1 och 3, Miljöbyggnad 3.12021Independent thesis Basic level (university diploma), 180 HE creditsStudent thesis
    Abstract [en]

    Sweden uses a large amount of energy within the housing and services sector and there is a greatneed to reduce the energy usage & heat demand of buildings. Using environmental certifications it ispossible to reward buildings that are dimensioned for lower energy usage and low heat demand fromrequirements demanded by the Swedish National Board of Housing, Building and Planning(Boverket). Miljöbyggnad 3.1 (Swedish Green Building Council) Indicator 1 Heat demand is todayassessed in relation to the inside enclosing area of the building, W/m2,Aoms, while Indicator 3 Energyusage is assessed in relation to heated floor area, kWh/m2,Atemp. Previous research indicates that thesequantities do not take into account how well the building is used but only how well it is dimensionedin terms of construction technology. Therefore it might be appropriate to introduce a quantity thattakes into account how well the building is used.

    The purpose of this case study is to raise a discussion if Boverket and Miljöbyggnad 3.1 today usessuitable quantities when it comes to grade energy efficient building and how different quantities cancome and affect a grading.

    This research presents a case study where an elementary- and a preschool using IDA ICE-modelsevaluates based on simulations for energy usage and heat demand. The results from the simulationsare compiled in diagrams to be able to see how different cases affect the grading based on whichquantities are being used. The quantities that are being used in this study is based on previousresearch and the different cases have been made to see which parameters affect the quantities.

    The study shows that depending on what is considered to be an energy efficient building, differentquantities may be applied for the assessment. The quantities used today in Miljöbyggnad 3.1 forIndicator 1 Heat demand and Indicator 3 Energy usage favors different types of buildings.kWh/m2,Aoms favors buildings with higher floor heights while kWh/m2,Atemp favors buildings withlower floor heights.

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  • 49.
    Andersson, Niklas
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Energieffektivisering av byggnad med enkla medel: en fallstudie på Hofors mödravårdscentral2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the central parts of Hofors a healthcenter is located which is included in Hoforshus AB's building stock, the building itself is divided into a main building and a smaller one in which the child health center and maternity care is located. The buildings are connected by a corridor substantially glazed. Now they are interested in maping the building's energyusage as this is relatively high, in addition, the users of the building had been dissatisfied with the indoor climate in both summer and winter. Because of the healtcare activities the owners were most interested in finding solutions that would not interfere with it.

    The study conducted has had a primary focus on the building envelope and above all on the glazed corridor’s impact on the rest of the building. One can assume that the high proportion of glass in this part of the building affects the indoor climate negatively keeping in mind the low U-value of the glass and the solar heat load, this gives during the summer when heat gain is not desired. A literature study to investigate how people perceive the climate as well as how to make a reliable simulation model of a building has been completed. The study resulted in an understanding of how the indoor climate is perceived and quantified, and also in an understanding of what is important in the collection of data for the simulation model.

    Keeping in mind how data should be collected according to the literature reviwe- have as much data as possible measured through surveys and own observations, blueprints have been studied and their validity has been investigated by measuring the building, blower door has been performed and temperature- and relative humidityloggning. Instantaneous values of the FTX system was made to calculate its efficiency. Linear thermal bridges have been investigated by finite element method in the program COMSOL Multiphysics 3.5. For validation of the simulated model the results of it were compared with the acutal measured energyconsumption of the building. The simulations were performed in BV2.

    The results of the study show, as expected, the glazed corridor’s negative impact on the building's indoor climate. Temperature was logged between 160412-160509 highest temperature was 30 ° C and minimum 15 ° C, which is more widespread than in other areas where the temperature was logged. The simulations that were performed on the glazed corridor shows that it consumes between 5000-5500 kWh on the area of 13.5 m2. Finally the study resulted in recommendations for the building that includes additional insulation of the attic, replacement of a smaller wall section, lowering the temperature by 1 ° C, as well as some maintenance measures to improve the indoor climate. The measures are believed to be possible to implement without significant interference with the health care acitivities. In addition the proposed measures seem profitable according to the pay of method.

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  • 50.
    Andersson, Nils
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Lindberg, Samuel
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    Dynamisk energieffektivisering med hjälp av elektrokroma fönster i ett svenskt klimat: En fallstudie av en simulerad kontorslokal med geografisk variabilitet.2022Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Det används stora mängder energi inom kontorslandskap för att reglera inomhusklimatet. Intresset har ökat för energisparande åtgärder både politiskt och privat. För kontorsbyggnader är fönster en stor andel av klimatskärmen vilket har en stor påverkan på värme- och kylvärmeenergin som tillförs in i kontorsbyggnaden.

    Elektrokroma fönster kan, genom att skicka en spänning till ett av fönstrets skikt, aktivt förändra sina egenskaper för att steglöst begränsa solinstrålning i en byggnad.   

    Denna fallstudie är framtagen för att undersöka var och hur elektrokroma fönster kan användas för att effektivisera inomhusklimatet, med betoning på kylbehov, i Sverige.

    Undersökningen gjordes genom att göra flertal simuleringar på en kontorslokal i IDA ICE där lokalen simuleras på olika orter. Orter varieras från norr till söder och från kust till inland. Fönsterfasaden simulerades även i olika väderstreck.

    Resultaten visar att användning av tekniken sänker inkommande värmeenergi genom fönster med runt 60 procent oavsett på omgivande medeltemperatur. Därför motiveras användandet bäst på sydliga fasader och vid orter nära kust eller stora vatten där solvärmelasten är som störst.

     

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