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  • 101.
    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.

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    Examensarbete
  • 102.
    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
  • 103.
    Amiri, Shahnaz
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy engineering. Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Energisystem.
    Economic and Environmental Benefits of CHP-based District Heating Systems in Sweden2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Future energy systems and thus the climate are affected by many factors, such as energy resources, energy demand, energy policy and the choice of energy technologies. Energy systems of the future are facing three main challenges; the steady growth of global energy demand, the energy resource depletion, as well as the increasing emissions of carbon dioxide (CO2) and other greenhouse gases and their impact on climate change. To meet the mentioned challenges with sustainability in mind, actions that increase energy efficiency and choosing an energy-efficient energy system which is cost efficient will be essential. Combined heat and power (CHP) plants and district heating and cooling could contribute greatly to increased system efficiency by using energy otherwise wasted.

    The aim of this study is to increase the understanding of how CHP-based district heating and cooling systems using different primary energy sources can contribute to more cost-efficient energy systems, which reduce global CO2 emissions, and to highlight the impact of some important parameters and measures on Swedish municipal district heating systems. An important assumption in this study is the estimation of CO2 emissions from electricity production, which is based on marginal electricity perspectives. In the short term, the marginal electricity is assumed to come from coal-fired condensing power plants while in the long term it consists of electricity produced by natural gas-fired combined cycle condensing power plants. This means that the local electricity production will replace the marginal electricity production. The underlying assumption is an ideal fully deregulated European electricity market where trade barriers are removed and there are no restrictions on transfer capacity.

    The results show that electricity generation in CHP plants, particularly in higher efficiency combined steam and gas turbine heat and power plants using natural gas, can reduce the global environmental impact of energy usage to a great extent. The results confirm, through the scenarios presented in this study, that waste as a fuel in CHP-based district heating systems is fully utilised since it has the lowest operational costs. The results also show how implementation of a biogas-based CHP plant in a biogas system contributes to an efficient system, as well as lowering both CO2 emissions and system costs. The results show that replacing electricity-driven (e.g. compression) cooling by heat-driven cooling using district heating (e.g. absorption chillers) in a CHP system is a cost-effective and climate friendly technology as electricity consumption is reduced while at the same time the electricity generation will be increased. The results of the study also show that there is potential to expand district heating systems to areas with lower heat density, with both environmental and economic benefits for the district heating companies.

    The results reveal that the operation of a studied CHP-based district heating system with an imposed emission limit is very sensitive to the way CO2 emissions are accounted, i.e., local CO2 emissions or emissions from marginal electricity production. The results show how the electricity production increases in the marginal case compared with the local one in order to reduce global CO2 emissions. The results also revealed that not only electricity and fuel prices but also policy instruments are important factors in promoting CHP-based district heating and cooling systems. The use of electricity certificates has a large influence for the introduction of biogas-based cogeneration. Another conclusion from the modelling is that present Swedish policy instruments are strong incentives for cogeneration with similar impact as applying external costs.

  • 104.
    Amiri, Shahnaz
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy engineering. Department of Management and Engineering, Division of Energy Systems, Linköping University, Linköping, Sweden.
    Henning, Dag
    Optensys Energianalys, Linköping, Sweden .
    Karlsson, Björn G.
    Department of Management and Engineering, Division of Energy Systems, Linköping University, Linköping, Sweden .
    Simulation and introduction of a CHP plant in a Swedish biogas system2013In: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 49, p. 242-249Article in journal (Refereed)
    Abstract [en]

    The objectives of this study are to present a model for biogas production systems to help achieve a more cost-effective system, and to analyse the conditions for connecting combined heat and power (CHP) plants to the biogas system. The European electricity market is assumed to be fully deregulated. The relation between connection of CHP. increased electricity and heat production, electricity prices, and electricity certificate trading is investigated. A cost-minimising linear programming model (MODEST) is used. MODEST has been applied to many energy systems, but this is the first time the model has been used for biogas production. The new model, which is the main result of this work, can be used for operational optimisation and evaluating economic consequences of future changes in the biogas system. The results from the case study and sensitivity analysis show that the model is reliable and can be used for strategic planning. The results show that implementation of a biogas-based CHP plant result in an electricity power production of approximately 39 GW h annually. Reduced system costs provide a profitability of 46 MSEK/year if electricity and heat prices increase by 100% and electricity certificate prices increase by 50%. CO2 emission reductions up to 32,000 ton/year can be achieved if generated electricity displaces coal-fired condensing power.

  • 105.
    Amiri, Shahnaz
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy engineering.
    Moshfegh, Bahram
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy engineering.
    Possibilities and consequences of deregulation of the European electricity market for connection of heat sparse areas to district heating systems2010In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 87, no 7, p. 2401-2410Article in journal (Refereed)
    Abstract [en]

    The objective of the study is to analyse the conditions for connection of residential buildings in heat sparse areas to district heating systems in order to increase electricity production in municipal combined heat and power plants. The European electricity market has been assumed to be fully deregulated. The relation between connection of heat sparse areas, increased electricity and heat production as well as electricity prices, fuel prices and emissions rights is investigated. The results of the study show that there is potential to expand the district heating market to areas with lower heat concentrations in the cities of Gavle, Sandviken and Borlange in Sweden, with both economic and environmental benefits. The expansion provides a substantial heat demand of approximately 181 GWh/year, which results in an electricity power production of approximately 43 GWh/year. Since the detached and stand-alone houses in the studied heat sparse areas have been heated either by oil boiler or by direct electricity, connection to district heating also provides a substantial reduction in emissions of CO(2). The largest reductions in CO(2) emissions are found to be 211 ktonnes/year assuming coal-fired condensing power as marginal electricity production. Connection of heat sparse areas to district heating decrease the system costs and provide a profitability by approximately 22 million EURO/year for the studied municipalities if the price of electricity is at a European level, i.e. 110 EURO/MWh. Sensitivity analysis shows, among other things, that a strong relation exists between the price of electricity and the profitability of connecting heat sparse areas to district heating systems.

  • 106.
    Amiri, Shahnaz
    et al.
    University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för energi- och maskinteknik. Department of Management and Engineering, Division of Energy Systems, Linköping University, Linköping, Sweden.
    Trygg, Louise
    Department of Management and Engineering, Division of Energy Systems, Linköping University, Linköping, Sweden.
    Moshfegh, Bahram
    University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för energi- och maskinteknik. Department of Management and Engineering, Division of Energy Systems, Linköping University, Linköping, Sweden.
    Assessment of the natural gas potential for heat and power generation in the County of Östergötland in Sweden2009In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 37, no 2, p. 496-506Article in journal (Refereed)
    Abstract [en]

    The aim of this study is to investigate the potential use of natural gas for heat and power production for the municipality of Linkoping, Norrkoping and Finspang in the County of Ostergotland, Sweden. The results of the study revealed that these three municipalities with the present heating demand can convert 2030 GWh/year of the present fuel mixed to natural gas. The expansion of natural gas provides the possibility to increase the electricity generation with approximately 800 GWh annually in the County of Ostergotland. The global emissions of CO(2) reduce also by approximately 490 ktonne/year by assuming the coal condensing power plant as the marginal power plant. The total system cost decreases by 76 Mkr/year with the present electricity price which varies between 432 and 173 SEK/MWh and with 248 Mkr/year if the present electricity price increases to 37% which is approximately corresponding to European electricity prices. Sensitivity analysis is done with respect to the different factors such as price of electricity, natural gas, etc. The findings show that increased price of electricity and increased district heating demand increases the profitability to convert to natural gas using CHP plant. (C) 2008 Elsevier Ltd. All rights reserved.

  • 107.
    Amiri, Shahnaz
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system. Department of Management and Engineering, Division of Energy Systems, Linköping University, Linköping, Sweden.
    Weinberger, Gottfried
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Increased cogeneration of renewable electricity through energy cooperation in a Swedish district heating system - A case study2018In: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 116, p. 866-877Article in journal (Refereed)
    Abstract [en]

    The present study of the district heating (DH) system in the city of Kisa, Sweden, shows how, through energy cooperation with a nearby sawmill and paper mill, a local energy company contributes to energy-efficient DH and cost-effective utilization of a new biofuel combined heat and power (CHP) plant. Cases of stand-alone and integrated energy systems are optimized with the linear program MODEST. The European power market is assumed to be fully deregulated. The results show clear advantages for the energy company to cooperate with these industries to produce heat for DH and process steam for industry. The cooperating industries gain advantages from heat and/or biofuel by-product supply as well. The opening to use a biofuel CHP plant for combined heat supply results in cogenerated electricity of almost 29 GWh/a with an increased biofuel use of 13 GWh/a, zero fuel oil use and CO2 emission reductions of 25,800 tons CO2/a with coal-condensing power plant on the margin and biofuel as limited resource. The total system cost decreases by −2.18 MEUR/a through extended cooperation and renewable electricity sales. The sensitivity analysis shows that the profitability of investing in a biofuel CHP plant increases with higher electricity and electricity certificate prices.

  • 108.
    Amunarriz Ollokiegi, Endika
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Electric heated windows: thermal comfort and energy use aspects2013Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
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    FINAL REPORT
  • 109.
    Anastasopoulou, Kyriaki
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Creation of a Low Energy Building with the help of Energy Simulation2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this Thesis Project, the creation of a Low Energy building was examined in order to investigate how complex was to select the suitable parameters and systems of the dwelling, aiming to achieve the lowest possible energy consumption in one year period. All the technologies implemented into the system intended to be as energy efficient and profitable as possible. Another objective of this study was also to present the potential of the system to produce a part of the consumed energy, through renewable energy sources, approaching by this way also the standards of a Zero Energy Building. Firstly, the floor plan of the 150 m2 detached house, was drawn in the designing program AutoCAD. In continuation, this 2D floor plan was imported into the simulation program as well as all the initial input data so as for the Base model of the building to be created For the analysis of the building, the Simulation Program IDA ICE 4.7 was used. Gradually, alternations and adjustments were made into the Base model. Different models were created planning to analyze their results and conclude to the proper solution. All the simulations run for one year time period in order to present the total energy usage, system’s losses and demands in each case. In addition, as for the current study, the location of the construction was Athens, all building’s characteristics were chosen to comply with the Greek Regulation for Low Energy Buildings. Finally, through the procedure followed after having accomplished a series of simulations, the final annually energy demands managed to be within the required limits.

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    fulltext
  • 110.
    Anavberokhai, Isah
    University of Gävle, Department of Technology and Built Environment.
    Introducing GIS and Multi-criteria analysis in road path planning process in Nigeria: A case study of Lokoja, Kogi State2008Independent thesis Advanced level (degree of Magister), 15 points / 22,5 hpStudent thesis
    Abstract [en]

    In planning a suitable road network, planners put into consideration factors like gradients or slope of the area, available land-use and soil type, community or national landmarks and governmental interest. These different considerations and interest make the planning process complex and as such there might be confusion of interest in the decision making. The use of GIS and Multi-criteria analysis has helped planners to achieve desired and more accurate results and as such reducing the complex nature in the planning process allowing different stakeholders to reach a general conclusion.

    Multi-criteria analysis (MCA) prevents the imposition of limit on the form of criteria and gives opportunity to decision makers to enter their own judgments. This provides a better communication among the decision makers and the entire community and as such creating a more open choice for analysis and possible changes if necessary. The aim of this thesis is to introduce the possibility of using GIS and MCA in road path planning in Nigeria, using Lokoja, the capital of Kogi state as a case study.

    In actualizing the aim, satellite images of the area of study was obtained from the Landsat home page and analyzed to derive the land-use map. The land-use over the area of study was classified into five different classes using the unsupervised method of classification. A DEM over the area of study was downloaded from the website of the Consortium of Spatial information (CSI) and the DEM was used to derive the slope map over the area of study and the analytic hierarchy process (AHP) method was used in weighting the criterions according to preference.

    As the conclusion of the analysis, a road path between two points was obtained. The start point of the road was located on an approximate coordinate of 219002, 958986 meters and the destination point on an approximate coordinate of 320322, 878101 meters. The start and destination point were selected randomly without any pre-knowledge of the area. The thesis has succeeded in showing that it is possible to determine a road path between two points using Geographic information system (GIS) and Multi-criteria analysis in Nigeria.

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    FULLTEXT01
  • 111.
    Anavberokhai, Isah
    University of Gävle, Department of Technology and Built Environment.
    Mapping land-use in north-western Nigeria (Case study of Dutse)2007Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis
    Abstract [en]

    This project analyzes satellite images from 1976, 1985 and 2000 of Dutse, Jigawa state, in north-western Nigeria. The analyzed satellite images were used to determine land-use and vegetation changes that have occurred in the land-use from 1976 to 2000 will help recommend possible planning measures in order to protect the vegetation from further deterioration.

    Studying land-use change in north-western Nigeria is essential for analyzing various ecological and developmental consequences over time. The north-western region of Nigeria is of great environmental and economic importance having land cover rich in agricultural production and livestock grazing. The increase of population over time has affected the land-use and hence agricultural and livestock production.

    On completion of this project, the possible land use changes that have taken place in Dutse will be analyzed for future recommendation. The use of supervised classification and change detection of satellite images have produced an economic way to quantify different types of landuse and changes that has occurred over time.

    The percentage difference in land-use between 1976 and 2000 was 37%, which is considered to be high land-use change within the period of study. The result in this project is being used to propose planning strategies that could help in planning sustainable land-use and diversity in Dutse.

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    FULLTEXT01
  • 112.
    Anbessa, Gedion Biredaw
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electrical Engineering, Mathematics and Science.
    Implementation of Spectrum Analysis Functionality for IQ-Signal.2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The spectrum analyzer is a standard tool used to measure signals in the frequency domain. Traditional spectrum analyzers are based on sweeping a local oscillator and using this to mix signals down to an intermediate frequency (IF) and, subsequently filter them with a filter of settable characteristics, called the Resolution Bandwidth (RBW). This is still the preferred method when the requirement on dynamic range of the signals being measured is large. However, this approach has the drawbacks of being relatively slow, not adaptive and flexible for some specific need and certain special measurement functionalities cannot be done due to the sweeping. Due to this, Ericsson production test development would like to perform software-based spectrum analysis on sampled In-phase and Quadrature (IQ) signals.

    In this thesis, the introduction of IQ-signals and synthetic spectrum analysis (SSA) are presented. The statistical properties of root mean-square (RMS) and sample detectors for standard spectrum analyzer are investigated. The effect of swept time on statistical properties of the RMS and sample detectors were investigated and the results are presented in this work. The results of swept time effect for sample detector show the change in the variance of the statistical properties when continuous wave (CW) and two-tone test signals were used, however, for bandlimited Gaussian test signal, the variance of the statistical properties is not changed. For RMS detector, the swept time using two-tone and Gaussian test signals show the change in the variance of the statistical properties. Whereas, for CW test signal the statistical properties result in shift from higher power distribution level to lower power distribution level with increase in sweep-time.

    The emulation of spectrum analysis functionalities (RBW, envelope detector and 0detectors) for IQ-signal has been implemented in MATLAB. The verification of the implemented functionalities has been done by investigating the statistical properties of RMS and sample detectors for SSA for various test signals. These were found to agree with standard spectrum analyzer results.

    Moreover, the comparison of spectral traces and statistical properties between implemented functionality and standard spectrum analyzer have done. The results are showing agreement with industrial standard spectrum analyzer results.

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    fulltext
  • 113.
    Andersen, Niklas
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Wind Turbine End of Life: Characterisation of Waste Material2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Wind power is growing fast all over the world, and in Sweden alone thousands of turbines has been installed the last few decades. Although the number of decommissioned turbines so far is very low, the rapid installation rate indicates that a similar rapid decommissioning rate is to be expected shortly. If the waste material from these turbines is not handled sustainably the whole concept of wind power as a clean energy alternative is challenged.

    This study aims to present an accurate estimate of the amounts of waste material that will be generated from wind turbines in Sweden during the coming decades, allowing the waste management industry to plan for this and by extension prevent unnecessary energy losses through imperfect waste treatment. It should also present helpful information on how problematic waste can be reduced or avoided.

    VindStat’s annual report, presenting installation date and other relevant data for most installed turbines in Sweden, has been used as the base for the calculations. Information on material composition in different types and sizes of wind turbines has been extracted from various life cycle assessments, and by using the available parameters in the data base each turbine has been assigned a specific amount of steel, iron, copper, aluminum, blade material and electronics. An average life time of 20 years has been assumed, based on prior research and comparison with empiric data, and the material of each turbine is therefore seen as generated waste 20 years after installation date.

    To calculate the amount of waste material from replacing faulty components, empiric data over replacement rates in further developed markets has been combined with a prognosis over future development of installed wind capacity in Sweden based on a method described by prior research. As no sufficient way to predict how the future second hand market for turbines and components has been found, three different possible scenarios have been investigated to see how this may affect waste amounts.

    The results show that annual waste will grow slowly at about 12 % increase per year until around 2026, and then the average increase is 41 % per year until 2034. By then, annual waste amounts are estimated to have reached 237 600 tonne steel and iron (16 % of currently recycled amounts), 2 300 tonne aluminium (4 %), 3 300 tonne copper (5 %), 343 tonne electronics (<1 %) and 28 100 tonne blade material. There is no industrial scale recycling method for commonly used blade materials, and a high strength steel developed by Sandvik is proposed as a fully recyclable material to consider for further research. A well-functioning second hand market is shown to possibly have a major impact on waste amounts, at least in postponing it until better recycling systems are in place.

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    Wind turbines end-of-life - Characterisation of Waste Material
  • 114.
    Andersen, Niklas
    et al.
    Energi Funktion Komfort Skandinavien AB, Nacka, Sweden.
    Eriksson, Ola
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Hillman, Karl
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Wallhagen, Marita
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Wind turbines’ end-of-life: Quantification and characterisation of future waste materials on a national level2016In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 9, no 12, article id 999Article in journal (Refereed)
    Abstract [en]

    Globally, wind power is growing fast and in Sweden alone more than 3000 turbines have been installed since the mid-1990s. Although the number of decommissioned turbines so far is few, the high installation rate suggests that a similarly high decommissioning rate can be expected at some point in the future. If the waste material from these turbines is not handled sustainably the whole concept of wind power as a clean energy alternative is challenged. This study presents a generally applicable method and quantification based on statistics of the waste amounts from wind turbines in Sweden. The expected annual mean growth is 12% until 2026, followed by a mean increase of 41% until 2034. By then, annual waste amounts are estimated to 240,000 tonnes steel and iron (16% of currently recycled materials), 2300 tonnes aluminium (4%), 3300 tonnes copper (5%), 340 tonnes electronics (<1%) and 28,000 tonnes blade materials (barely recycled today). Three studied scenarios suggest that a well-functioning market for re-use may postpone the effects of these waste amounts until improved recycling systems are in place.

  • 115.
    Andersen, Olav
    et al.
    Ericsson.
    Björsell, Niclas
    University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för elektronik. University of Gävle, Center for RF Measurement Technologies.
    Keskitalo, Niclas
    University of Gävle, Center for RF Measurement Technologies. University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för elektronik.
    A Test-Bed Designed to Utilize Zhu’s General Sampling Theorem to Characterize Power Amplifiers2009In: Instrumentation and measurement technology conference 2009 I2MTC '09 IEEE, Singapore, 2009, p. 201-204Conference paper (Refereed)
    Abstract [en]

    Characterizing power amplifiers require test set-ups with performance superior to the power amplifiers. A commonly used method is to use an IQ-demodulator. However, problem arises due to imperfections in the demodulator such as IQ-imbalance; an alternative method is to use a direct down converter to intermediate frequency. The drawback then is the limited bandwidth. However, the required bandwidth of the ADC does not need to be exceptional. According to Zhu’s general sampling theorem is it enough to sample the output signal at the Nyquist rate of the input. However, even though the required sampling rate is reduced the demands on the analog bandwidth remains. Unfortunately, commercially available instruments such as vector signal analyzers can not be used for this purpose since their analog bandwidth is too small. In this paper a test-bed is designed to utilize the Zhu’s general sampling theorem. The RF front-end has frequency range of 500 MHz – 2.7 GHz and a bandwidth of 1 GHz. All performance data are verified with measurements.

  • 116.
    Andersen, Olav
    et al.
    Ericsson AB, Gävle Sweden.
    Wisell, David
    Ericsson AB, Gävle, Sweden.
    Keskitalo, Niclas
    Ericsson AB, Gävle, Sweden.
    Stenvard, Patrik
    Ericsson AB, Gävle, Sweden.
    Cost effective high performance modular instrumentation, signal generation and signal analysis for future mobile communication systems2007In: 2007 IEEE Autotestcon: proceedings. Vol. 1 AND 2, 2007, p. 660-668Conference paper (Refereed)
    Abstract [en]

    A decrease in life cycle cost is a key issue for testing of mobile communication systems. The rapid development and edge technology requires high performance instruments and state of the art measurement technology. It is desired to use virtual/synthetic instruments and put the measurement technology in software independent of hardware, i.e. software driven measurements. Increased flexibility and modularization, both in hardware and software, are requirements to support the cost decrease. The hardware basis is signal generation and signal analysis.

    In this paper state of the art signal generation and signal analysis capabilities are demonstrated in a modular and flexible architecture. A direct IF synthesis is used to generate 1 WideBand Code-Division Multiple Access (WCDMA) carrier with more than 72 dB Adjacent Carrier Leakage Ratio (ACLR) 2 carrier with more than 68 dBc ACLR over a total bandwidth of 100 MHz. The signal analysis capabilities, ACLR performance, for a WCDMA carrier is better than -70 dBc and for a continuous wave better than -85 dBc over a bandwidth of 42.5 MHz. The critical down converter in the set up doesn’t degrade the performance.

  • 117.
    Andersen, Olav
    et al.
    Ericsson Telecom AB, Gävle, Sweden.
    Wisell, David
    Ericsson Telecom AB, Stockholm, Sweden.
    Staenvard, Patrik
    Ericsson Telecom AB, Gävle, Sweden.
    Keskitalo, Niclas
    University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för elektronik. University of Gävle, Center for RF Measurement Technologies.
    Extending the Bandwidth and Dynamic Range of Old RF Instruments to Meet State-of-the-Art Performance, Using a Synthetic Instrument Approach2009In: IEEE Transactions on Instrumentation and Measurement, ISSN 0018-9456, E-ISSN 1557-9662, Vol. 58, no 2, p. 248-254Article in journal (Refereed)
    Abstract [en]

    A decrease in life cycle cost is a key issue for testing mobile communication systems. The rapid development and edge technology requires high-performance instruments and state-of-the-art measurement technology. New investments are expensive, but even older generation instruments are capable of extending their bandwidth and dynamic range to meet even the latest Third-Generation Partnership Project (3GPP) cellular measurement requirements by the addition of external hardware using a synthetic instrument approach. The novelty of this paper is the high performance on the most crucial parameters, i.e., the dynamic range and bandwidth achieved by only replacing some parts of the legacy instrument. Moreover, the demonstrated direct IF synthesis has a high degree of novelty at wide modulation bandwidths. It is desired to use virtual/synthetic instruments and make the signal processing in the software independent of the hardware, i.e., software-defined measurements (SDMs). In this paper, a state-of-the-art experimental setup for signal generation and signal analysis is demonstrated. A direct IF synthesis is used to generate a wideband code-division multiple-access (WCDMA) carrier with more than 72-dB adjacent carrier leakage ratio (ACLR) up to 12 parallel carriers with more than 68-dBc ACLR over a total bandwidth of 100 MHz. The signal analysis capabilities (e.g., ACLR performance) for a WCDMA carrier is better than -70 dBc and for a continuous wave better than -85 dBc over a bandwidth of 42.5 MHz. The critical RF downconverter in the setup is carefully designed not to degrade the dynamic range performance.

  • 118.
    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
  • 119.
    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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  • 120.
    Andersson, Daniel
    et al.
    Radarbolaget.
    Björsell, Niclas
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Ottoson, Patrik
    Radarbolaget.
    Rönnow, Daniel
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Sandberg, Mats
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Radar Images of Leaks in Building Elements2015In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 78, p. 1726-1731Article in journal (Refereed)
    Abstract [en]

    Through leakage in the building envelope there is a penetration of air, water vapor and particles. The degree of leakage of air can be quantified by existing methods. However, the location of adventitious openings is often not known. In order to overcome the limitations in existing methods, a non-contact and non-destructive method based on ultra-wide bandwidth radar technology is suggested. A test-bed is designed that can measure with different polarization to be able to detect flaws in different directions. Initial measurements shows promising results for further development of the method of using radar images to find leaks in building elements.

  • 121.
    Andersson, Daniel
    et al.
    Radarbolaget, Gävle.
    Wallin, Kjell
    Radarbolaget, Gävle.
    Javashvili, Otar
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    Beckman, Claes
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electronics, Mathematics and Natural Sciences, Electronics.
    M-Sequence UWB Radar for Industrial Applications2010In: Program of GigaHertz Symposium 2010, March 9-10, at Lund University, 2010Conference paper (Other academic)
    Abstract [en]

    Ultra Wideband Radar has the potential of dramatically improving the control and surveillance of industrial processes in confined areas. An example is the application of UWB radar for surveillance of furnaces for heath treatment of steel billets developed by Radarbolaget in Gävle.

    In our installation at AB Sandvik Materials Technology, we have shown that by using a non-destructive UWB Radar technique it is possible to visualize in real-time the ongoing process inside the furnace behind a 0.5 m thick ceramic wall. Since the operating temperature inside the furnace is 1200 °C, there is today no other known method capable of visualizing the process for the operator of the furnace. The system is therefore designed to sustain high temperatures and powerful electromagnetic disturbances while performing measurement with wide dynamics and high stability.

    The design of this radar is based on the idea of transmitting a continuous m-sequence and then detecting the correlated impulse response (see figure below). The wide bandwidth is a requirement for obtaining high spatial accuracy and resolution but puts further requirements on the design of the antennas and the electronics. Our results show that with this technique it is possible to determine the deformation of the steel billets inside the furnace with an accuracy of less than 5 mm. The radar system is also able to detect deformations in the furnace wall

    The m-sequence radar has many advantages over other UWB radar technologies since it e.g. does not require many analogue components. Its performance is a result of the choice of code length, sampling rate and averaging. However, the resolution is still limited by the impulse response of the analogue antenna (ringing).

    In this paper system parameters that affect the overall performance of an m-sequence radar are reviewed and means of enhancing its performance are discussed.

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  • 122.
    Andersson, David
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Olsson, Philip
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Hur kan en skola med högre energianvändning än det svenska genomsnittet energieffektiviseras?: Energikartläggning2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The European Union as a whole is one of the largest energy users and has one of the world's largest greenhouse gas emissions. To reduce global warming, targets have been set to ensure that the average temperature on the earth does not increase more than 2 degrees since the pre-industrial time. Nearly 40% of Sweden's total energy use comes from the building and services sector which in context with that the 2020 targets approaching contributes to the increased need of higher energy efficiency of buildings. Energy audits is a tool for determining what has the greatest potential for saving energy before efficiency measures occurs.

    The thesis includes an energy audit of Trödje primary and middle school, administered by Gavlefastigheter. The study was performed using IDA Indoor Climate and Energy simulation tool. IDA ICE was used to modulate the existing building where all data for the school was included. The vision of the thesis is to investigate how much energy which is possible to save through energy saving measures and which action that is most effective.

    The potential energy saving in the school is high, the school uses 42.6 kWh/m2year more than the average for Gavlefastigheter schools, which corresponds to 21 %. The results show that the complexity of the school and the reconstruction, also called the paviljong, are a major factor in the high energy consumption. The school's energy use has a potential to decrease by 17 %, which did not correspond to the 25 % target set for the work. The work shows that the greatest savings potential exists through the exchange of windows and heat exchangers in the ventilation system, but also that the measures that are assumed to give the greatest savings are not always the most effective.

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  • 123.
    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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  • 124.
    Andersson, Emelie
    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.
    Aziz, Shniar
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Energy Systems and Building Technology.
    En jämförelse mellan gröna-, metall- och gråa tak för ett oisolerat parkeringshus utifrån dess olika temperaturer och dagvattenhantering2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Since climate change increases and changes constantly, it contributes to higher average temperatures, ice melting and has a great impact on our ecosystem. This will then lead to a warmer climate, which means increased precipitation and milder winters. One of the reasons to climate change is urbanization, meaning people moving to the cities. To succeed in changing the climate, international cooperation and common goals are required. At the northern part of Brynäs, in the municipality of Gävle, work is currently in progress around the area where the factory of Läkerol was once standing. The area continues to be rebuilt and the outcome will eventually be called Godisfabriken. There, amongst other, a car park will be built for the newly built homes. The aim of this study is to compare metal roofs, grey concrete roofs and green roofs within the two aspects of stormwater management and temperature. Then analyse which alternative of these three roofs would be most advantageous for the car park of Godisfabriken.

     

    The focused roofs are green, metal and concrete. A green roof is when it's completely or partly covered by a layer of vegetation and metal roofs are different sheet roofs with steel and aluminium-zinc. Grey roofs are made of concrete which works as both floor and ceiling. A building's roof affects which air temperature the surroundings has with its slope, vegetation and surrounding buildings. Another problem with urbanization and a warmer climate is stormwater management, which means rain and melted snow from roofs, parking areas and other hard surfaces.

     

    The method includes a literature study and calculations. The literature study gave research on temperature for all roofs as well as stormwater management for green roofs. Calculations were made for stormwater management and temperature with its flow, absorption, reflectance and heat transfer.

     

    The literature study and the calculations showed that green roofs have a high SRI value of 80 while the remaining roof is at around 40. The higher SRI, the lower surface temperatures on the material. This is proven in both methods when green roofs according to the literature study received a maximum surface temperature of 38 °C and 48 °C. According to the literature study green roofs can preserve more than 50 % of the rainwater. They also had a water flow rate of 1.97 l/s, which is less than half of what the metal roof got in the calculations. Since green roofs had both low air and surface temperatures, as well as longer drainage times and most absorbed water, green roofs are a more suitable choice than metal and grey concrete.

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  • 125.
    Andersson, Fredrik
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Utveckling av GIS-applikation för effektivisering av planeringsarbeten för infrastruktur2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Planeringsarbeten för infrastruktur sker ofta med hjälp av speciella programvaror som CAD för att skapa ritningar på kartor över områden där tänkta infrastrukturer skall utvecklas. Som en effektivisering för dessa arbeten handlar denna studie om implementering av en GIS-applikation för att motivera fördelar med GIS och sättet för hantering samt visualisering av geografisk information. En webbapplikation som hanterar baskartor samt överliggande vektorlager för infrastruktur utvecklas, samt även att samma kartdata över infrastrukturen kopplas till en mobilapplikation för att effektivisera eventuella inventeringsarbeten av infrastrukur med hjälp av GPS för att kunna positionera infrastruktur på ett bra sätt. Tekniken bakom utvecklingen bygger på HTML, CSS och JavaScript samt molntjänstlagrin av infrastruktursdata i en geodatabas . GIS-applikationen sammanställer svar på frågor som bevisar hur GIS på ett tillfredställande sätt mycket väl skulle kunna implementeras och användas praktiskt i ett utvecklingsarbete för infrastruktur i dagens morderna samhälle. 

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  • 126.
    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.
    Numerical and experimental study of confluent jets supply device with variable airflow2019Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    In recent years, application of confluent jets for design of ventilation supply devices has been studied. Similarly, numerus studies have been made on the potential and application of variable air volume (VAV) in order to reduce the energy demand of ventilation systems. This study investigates the combination of supply devices based on confluent jets and VAV, both in terms of the nearfield flow behavior of the device and the impact on thermal comfort, indoor air quality and energy efficiency on a classroom-level space when the airflow rate is varied.

    The method used in this study is an experimental field study where the confluent jets-based supply devices were compared to the previously installed displacement ventilation. The field study evaluated the energy efficiency, thermal comfort and indoor air quality of the two systems. In the case of the confluent jets supply devices, airflow rate was varied in order to see what impact the variation had on the performance of the system for each airflow rate. Furthermore, the confluent jets supply devices were investigated both experimentally and numerically in a well insulated test room to get high resolution data on the particular flow characteristics for this type of supply device when the airflow rate is varied. The results from the field study show nearly uniform distribution of the local mean age of air in the occupied zone, even in the cases of relatively low airflow rates. The airflow rates have no significant effect on the degree of mixing. The thermal comfort in the classroom was increased when the airflow rate was adapted to the heat load compared to the displacement system. The results lead to the conclusion that the combination of supply devices based on confluent jets can reduce energy usage in the school while maintaining indoor air quality and increasing the thermal comfort in the occupied zone.

    The results from the experimental and numerical study show that the flow pattern and velocity in each nozzle is directly dependent on the total airflow rate. However, the flow pattern does not vary between the three different airflow rates. The numerical investigation shows that velocity profiles for each nozzle have the same pattern regardless of the airflow rate, but the magnitude of the velocity profile increases as the airflow increases. Thus, a supply device of this kind could be used for variable air volume and produce confluent jets for different airflow rates.

    The results from both studies show that the airflow rate does not affect the distribution of the airflow on both near-field and room level. The distribution of air is nearly uniform in the case of the near-field results and the room-level measurement shows a completely uniform degree of mixing and air quality in the occupied zone for each airflow rate. This means that there is potential for combining these two schemes for designing air distribution systems with high energy efficiency and high thermal comfort and indoor air quality.

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  • 127.
    Andersson, Harald
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Cehlin, Mathias
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Moshfegh, Bahram
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Energy-Saving Measures in a Classroom Using Low Pressure Drop Ceiling Supply Device: A Field Study2016In: 2016 ASHRAE Winter Conference Papers, ASHRAE, 2016Conference paper (Refereed)
    Abstract [en]

    Between 1990 and 2006 the energy use by ventilation systems in Swedish schools doubled. This is explained by high airflows in schools because of the high occupant density. Studies show that 87% of Swedish schools use constant air volume (CAV), and it is estimated that a change to variable air volume (VAV) could save 0.12-0.33 TWh (4.1*10(12) - 1.1*10(13) Btu) per year. Therefore the aim of this study is to investigate whether it is possible to replace displacement ventilation (DV) with mixing ventilation (MV) to create a comfortable indoor climate in a typical classroom and at the same time decrease the energy use by using VAV and Low Pressure Drop Ceiling Supply Device (LPDCSD). The study used two LPDCSDs which consist of circular channels with 190/228 round jets placed in an interlocking pattern, with a horizontal one/two-way-direction. The field study was carried out in a school which is intended to be extensively renovated. The school currently has DV and CAV. The study was carried out by installing MV with LPDCSD in one of the typical classrooms. Several different air-flow rates were investigated using tracer-gas technology to measure the local mean age of the air in the occupied zone. Simultaneously, thermal comfort and vertical temperature gradients were measured in the room. The results show nearly uniform distribution of the local mean age of air in the occupied zone, even in the cases of relatively low air-flow rates. Since the mixing of air is more or less the same in the entire occupied zone VAV can be used to reduce air-flow rate based on the desired CO2-level. Because of the number of students in each classroom and the fact that changes in air-flow rates have no significant effect on the degree of mixing, it is possible to reduce the air-flow rates for extended periods of time. Finally, since the LPDCSD has a lower pressure-drop than the currently used supply devices and it is possible to use VAV to lower the airflows in cases with reduced heat loads, it is possible to significantly reduce the energy usage in the school while maintaining the IAQ, increasing the thermal comfort and the available floor area of the occupied zone.

  • 128.
    Andersson, Harald
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Cehlin, Mathias
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Moshfegh, Bahram
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Experimental and numerical investigations of a new ventilation supply device based on confluent jets2018In: Building and Environment, ISSN 0360-1323, E-ISSN 1873-684X, Vol. 137, p. 18-33Article in journal (Refereed)
    Abstract [en]

    In developed countries, heating, ventilation, air conditioning (HVAC) systems account for more than 10% of national energy use. The primary function of a HVAC system is to create proper indoor environment. A number of ventilation strategies have been developed to minimize HVAC systems’ energy use whilst still maintaining a good indoor environment. Among these strategies are confluent jet ventilation and variable air volume. In this study, an air supply device with a novel nozzle design that uses both of the above-mentioned strategies was investigated both experimentally and numerically at three different airflow rates. The results from the numerical investigation using the SST k - ω turbulence model regarding velocities and flow patterns are validated by experimental data carried out by Laser Doppler Anemometry. The results from both studies show that the flow pattern and velocity in each nozzle is directly dependent on the total airflow rate. However, the flow pattern does not vary between the three different airflow rates. The numerical investigation shows that velocity profiles for each nozzle have the same pattern regardless of the airflow rate, but the magnitude of the velocity profile increases as the airflow increases. Thus, a supply device of this kind could be used for variable air volume and produce confluent jets for the airflow rates investigated.

  • 129.
    Andersson, Helena
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Åhsberg, Mela
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Debiteringsmodell för interna transporter: Hur en debiteringsmodell kan förändra beställningsbeteende och sänka kostnader2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Transfer pricing is the price of goods or services supplied between units within a larger company. It turns out that transfer prices can make it possible for a company to be more effective and direct the company towards the common targets. A payment model can be used to connect internal charging for a completed delivery, where a written request is sent electronically to the customer with information about the amount and in which account the money should be placed. The specified price is based either on the basis of a price list that is updated continuously, or calculated immediately after a completed delivery. By using the service levels in a payment model the ordering behavior in the internal logistics can be changed if a manager makes the workers aware of how their choices affect the production unit's finances.

     

    The purpose of this study is to investigate whether a payment model for internal transport can change ordering behaviors and reduce costs for internal logistics. The purpose has been filled by performing a literature review on the subject which has been conducted on a case company where the internal ordering behavior and the current payment model have been studied. After examining and documenting of the current situation on the case company, a new payment model has been developed. The new payment model consists of hard and soft factors, where the factors are strongly linked with each other and are important to change unwanted behaviors.

     

    The result of the survey shows that a payment model alone cannot change unwanted ordering behavior. Unwanted ordering behavior can only be changed with the combination of service levels and strong leadership.  The target is to make workers aware that the choice of service level affects the final price of an order. It can only happen if managers motivate the workers to choose a service level that can reduce production unit ordering costs. It is however important to note that the payment model itself must be supported by a strong leadership that promotes a change and that workers receive training in how the payment model works and knowledge of what management's view of the model is.

     

    With this background, this study aims to solve both the case company’s practical problems with internal transport costs and increasing knowledge about payment models and how these can be used to change unwanted behaviors.

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  • 130.
    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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  • 131.
    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
  • 132.
    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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  • 133.
    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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  • 134.
    Andersson, Maria
    et al.
    Department of Psychology, University of Gothenburg, Göteborg, Sweden .
    Eriksson, Ola
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    von Borgstede, Chris
    Department of Psychology, University of Gothenburg, Göteborg, Sweden .
    The Effects of Environmental Management Systems on Source Separation in the Work and Home Settings2012In: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 4, no 6, p. 1292-1308Article in journal (Refereed)
    Abstract [en]

    Measures that challenge the generation of waste are needed to address the global problem of the increasing volumes of waste that are generated in both private homes and workplaces. Source separation at the workplace is commonly implemented by environmental management systems (EMS). In the present study, the relationship between source separation at work and at home was investigated. A questionnaire that maps psychological and behavioural predictors of source separation was distributed to employees at different workplaces. The results show that respondents with awareness of EMS report higher levels of source separation at work, stronger environmental concern, personal and social norms, and perceive source separation to be less difficult. Furthermore, the results support the notion that after the adoption of EMS at the workplace, source separation at work spills over into source separation in the household. The potential implications for environmental management systems are discussed.

  • 135.
    Andersson, Martin
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Berge, Nils
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy system.
    Energi- och miljökonsekvenser vid energieffektivisering av belysning och installation av solceller på Nacka Forum i Stockholm2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The use of energy is increasing worldwide and due to the threat of global warming more and more discussions are made about how the consumption could be reduced and at the same time more sustainable solutions is requested.Buildings consume 40 % of the total global energy where most of it comes from fossil fuels. To reduce the impact of the environment the EU (European Union) has set several goals for that where one is reducing its CO2-emission with 20 % compared to 2008 by the year 2020. One way to do so is from using more efficient technology. This work was made to reduce Nacka Forums electricity bills and that after it had been requested of their owner Unibail-Rodamco. The authors have only looked for solution in areas which the property owners are responsible for like services areas and public spaces. Ideas for reducing their energy use were obtained through studying literature. That study also showed that shopping malls use a lot of energy, especially electricity which mostly is consumed by the building’s lighting. Something that is becoming increasingly more common on buildings is solar cells. Solar cells do not only cut the electricity costs but also decreases the demand on fossil fuels. The shopping mall seemed to have good conditions for such an installation so an investigation was made to see if that could be useful. A plant with a power of 100 kWp was calculated to need 920 m2 roof surface and would yearly produce 93 534 kWh which the authors conclude that it would be a good investment and also highlights that an even bigger plant should be considered. After observing the lights two new solutions were proposed where LED-lamps was considered to be the best source for replacement. Just changing all the light sources would cut the electricity costs a lot but since the existing luminaires was considered to be at the end of their technical lifetime the best solution would therefore be to change both luminaires and light sources. Such solution would decrease the energy use with 544,4 MWh/year and has a payback period of 3,3 years. That energy saving would decrease the CO2-emission with 218 ton/year.This work shows that regardless of which solution that is chosen both of them would decrease the energy use and CO2-emission with 50 %.One of the stores in the shopping mall was using a lot of light which caused problem with the thermal comfort. Despite that, the store does not exceed the limit of 50 W/m2 that is set from the property owner. Such low requirements might hinder any efforts to reduce the energy use and also contribute to unnecessary heat.

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  • 136.
    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
  • 137.
    Andersson, Martin
    et al.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Sosa, Mario
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Sjöberg, Sören
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Mechanical Engineering.
    Olofsson, Ulf
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Effect of Assembly Errors in Back-to-Back Gear Efficiency Testing2015In: Power Transmission Engineeing, Vol. December, p. 72-77Article in journal (Other academic)
  • 138.
    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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  • 139.
    Andersson, Michael
    et al.
    Department of Transportation and Logistics Chalmers University of Technology.
    Olsson, Göte
    University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för industriell ekonomi.
    A simulation based decision support approach for operational capacity planning in a customer order driven assembly line1998In: Proceedings of the 1998 Winter Simulation Conference / [ed] Medeiros, D. J., Watson, E. F., Carson, J. S., and Manivannan, M. S., IEEE , 1998Conference paper (Refereed)
    Abstract [en]

    The paper reports on a project in the area of simulation based decision support (SBDS) at the operational level of the manufacturing system. The purpose of the project was to explore and describe the possibilities to use a standard discrete event simulation package for capacity planning in a situation where labor was a primary and scarce production resource. This has been done through a case study at a Radio Base Station (RBS) assembly line at Ericsson Radio System, Gavle in Sweden. Results from the study are a conceptual structure for a SBDS system and a prototype simulation system tailored for the RBS-2000 assembly line. The system has been tested in a simulated environment and results indicate a delivery precision improvement of eleven percent. Conclusions from the study are that this kind of tool for operational decision support offers a flexible decision support environment and that the need for high quality information and information collecting systems are crucial for the success of such tools.

  • 140.
    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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  • 141.
    Andersson, Niklas
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Mechanical Engineering.
    Modelling of metal removal rate in titanium alloy milling2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Titanium is one of fourth most abundant structural metal in earths soil. It is in a composition with other elements, forming titanium alloys. These alloys are used in many different areas, such as medical, energy and sports, but is most commonly used in aerospace applications. Titanium alloys have different solid phases, α, α+β and β depending on temperature and the amount of α and β-stabilizers.When machining titanium alloys, one of the most important factors to control is the temperature in the cutting zone. The built-up heat in the cutting edge of the tool, are connected to titanium alloys low thermal conductivity and high heat capacity, which means that the alloy has low heat conduction from the cutting zone. The temperature is strongly depending on the cutting speed, which is the relative speed difference between the cutting tool and the workpiece. Many studies and research work have been conducted surrounding this fact, focusing on the physical and chemical quantities, to model tool wear progression and how this affects the tool life and the metal removal. These models are often implemented and analyzed in finite element software providing detailed but time-consuming solutions.The focus for this work have been on developing a suitable tool life expectancy model, using design of experiments in combination with metamodeling to establish a model connecting cutting parameters and measured responses in terms of tool life, from a conducted milling experiment. This models where supposed to provide a platform for customer recommendation and cutting data optimization to secure reliable machining operations. The study was limited to focus on the common α+β titanium alloy 6Al-4V. The outcome and conclusion for this study, is that the tool life is strongly connected to the choice of cutting speed and the radial width of cut and that these parameters can be predicted by the two models that have been develop in this project. The models ensure the highest possible metal removal rate, to selected parameters.

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  • 142.
    Andersson, Rabé
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Electrical Engineering, Mathematics and Science, Electronics.
    Exploring Baxter Robot and Development of Python algorithms to Execute Holding, Lifting and Positioning Tasks2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The greatest feature of using a Baxter robot among other industrial robots is the ability to train this robot conveniently. The training of the robot could be done within a few minutes and it does not need so much knowledge of programming. However, this type of training feature is limited in functionality and needs frequent updating of the software and the license from the manufactural company. As the manufacturer of Baxter Robot no longer exists due to a merger, the thesis has twofold aims, (1) Exploring different functional, installation, calibration, troubleshooting and hardware features of the Baxter robot and (2) demonstrate the functionality of Baxter to perform general tasks of holding, lifting and moving of test objects from one desired position to another position using custom-made programs in Python. Owing to this, details about different software and hardware aspects of Baxter robot is presented in this thesis. Additionally, systematic laboratory tutorials are also presented in appendices for students who want to learn and operate the robot from simple to complicated tasks. In order to keep the Baxter operational for students and researchers in future, when there is no more help available from its manufacturer, this thesis endeavour to cover all these aspects. Thus, the thesis presents a brief understanding of how to use the Baxter Robot in a simple and efficient way to perform a basic industrial task. The kinematics part will show the concepts of forward and inverse kinematics and the DH (the Denavit–Hartenberg) parameters that are important to understand the end-effector position according to the world frame that will give the knowledge of those who are interested in the kinematics part of Baxter robot. The work of the thesis will make it easier to understand how to program a Baxter robot by using Python language and using the simplest way to move the arm to certain positions. The ROS principles, kinematics and Python language programs will provide a good platform to understand the usability of Baxter robot. Furthermore, easy to use laboratory tutorials are devised and are presented in the appendices. These laboratory tutorials will improve the understanding of the readers and provide a step-by-step guide of operating Baxter robot according to the principles of Robotics. In addition to all these points above, the thesis shows useful functions that are built in ROS (Robot Operating System) that make it easier to program the robot in an untraditional way which is one of a contribution of this thesis itself. The usual way to program the robots, in general, is to study the robot kinematics and calculate the position of the end-effector or the tool according to some frame or the world coordinate frame. This calculation can be done by the forward kinematics or the inverse kinematics. The set of programming Baxter robot in this thesis is not the complex calculation of the forward or the inverse kinematics. The tf (transform)tool in ROS has made it easier to reach the joint angles and program Baxter robot using Python.

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  • 143.
    Andersson, Robin
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering.
    Energibalansberäkning för flerbostadshus: projekterad energianvändning jämfört med beräknad energianvändning med uppmätta värden för Gävle Strand Etapp 12011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The estimated amount of energy that a building consumes during one year indicates whether it contributes to a sustainable society or not. The communal company, AB Gavlegårdarna , that rents out apartments, works not only with designing proposals for solutions for the future housing , they also work with improving their stock when it comes to energy consumption. The multi-family buildings of Gävle Strand Phase 1 were completed in 2008 with a population of twelve buildings that are shaped in four ways.

     

    During the planning phase a consultant was hired to calculate the how much energy these buildings would have to purchase and came up with an energy use of 92 kWh/m2,year. Gavlegårdarna’s own calculations are based on the actual values obtained for each apartment and in September 2009 and they showed a mean value for the whole stock, which was 114 kWh/m2,year.

     

    AB Gavlegårdarna want to find a solution to the problem and reduce the extra cost that Gävle Strand Phase 1 has given rise through increased use of energy. They want to perform precise calculations on each building's energy use. The problem can be formulated as follows:

    How much influence does the malfunction of a heat exchanger in a balanced ventilation system have on the total energy consumption in apartment buildings? Can a house among the various geometrically designed houses of a stock be considered to be representative when calculating the energy use of the stock as a whole?

    The report deals with a number of U-value and area calculations, ventilation and air leakage assessments, domestic hot water use and energy user behavior of the residents, to work out how much a simulated building uses in terms of specific energy, with unit kWh/m2,year. An building simulation program called BV2 2010was utilized.

    The results show that the majority of the buildings located in Gävle Strand Phase 1 have higher energy consumption than the consultant's basic case. This is due to several factors but the main causes of the high residential energy use is the low temperature efficiency in the FTX-system heat exchanger, the residents’ behavior and in some cases relatively high usage of hot water.

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  • 144.
    Andersson Skått, Kristian
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    Bergkvist, Kristoffer
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    Småhusfastigheters värdeförändring vid större infrastrukturprojekt: En studie av ombyggnationen E4 Sundsvall2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Infrastructure investments is a large part of the regional development in Sweden, researchers in the subject agrees that investment in infrastructure generate increased economic development, one thing they still share a disagreement in which calculating methods are suitable. Are there any winners or losers in infrastructure projects, for example, smaller cities in the countryside where highways have previously passed, have they benefited from a quicker and easier commuting to the city, or have they been adversely affected when the highway has been given a new stretch?

    This research report focuses in one of the largest infrastructure investments in northern Sweden, European road 4 (E4) through Sundsvall. The research, combined with location-based sales comparison method and local analyzes, will show what effect market values will have on the houses real estate’s and what influence the road construction might have regarding to the values of the properties.

    The results of these studies are shown trough the average changes in property prices in the areas of Njurundabommen, Nedre Haga/Skönsberg, Nolby/Kvissleby and Västbo. However, the result was shown to have too few transactions, which is common in local level sales analyzes. This generates uncertainty in the result, meaning that the values can be large in relation to the actual sales development. The uncertainty was minimized in the results by merging two similar areas, which finally gave a result that indicates that the areas in the study had a more negative development towards Sundsvall and Sweden, since the area received a new infrastructure in the form of the E4 Sundsvall.

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  • 145.
    Andersson, Tommy
    et al.
    University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för elektronik. University of Gävle, Department of Technology and Built Environment.
    Algilany, Gazwan
    University of Gävle, Department of Technology and Built Environment, Ämnesavdelningen för elektronik. University of Gävle, Department of Technology and Built Environment.
    Konstruktion Signalgenerator2009Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    SAAB Aerotech division FGR in Arboga builds and develops equipment and components used in both military and civilian applications. To build a test system for a specific project that SAAB is responsible for requires a simple signal generator that can provide a pulse modulated signal. The need to buy a new advanced signal generator for example from Agilent is not as profitable as the instrument is expensive and contains features that SAAB does not require in their applications and test systems. That was the reason why SAAB offers two students a thesis where the goal is to construct a signal generator in accordance with what SAAB requests.

    This thesis contains several different phases. The first step was a meeting with our supervisor Mats Bergman and by reading the data sheets for components to be used in the project, with these information and specifications that we have received from SAAB we started to construct the signal generator.

    What we did during the construction work was to simulate and draw a schematic to be able to design the circuit board. Simulation was done both in software and on laboration board. The card is then ordered from a circuit board manufacturer in Bulgaria. On the finished card the components will be fitted. Then the card will plugged in into a rack and then presented finished as a signal generator that can be used in a test system.

    The final results of all phases are satisfactory in the part of design and laboratory work. The finished mother board was tested and test results corresponded well with the theory. The final results will be presented with a spoken presentation at the University of Gävle and at SAAB Aerotech in Arboga division FGR

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  • 146.
    Andersson, Towe
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Lindgren, Matilda
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Fastighetsbestämning och särskild gränsutmärkning i Sverige2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis is to describe property definition and special boundary demarcation and to analyze the differences between the two cadastral procedures. Property boundaries, especially unlawfully determined boundaries created through unofficial parcelling, can create conflicts between landowners and make it diffi-cult to know which land that a property contains of. It is possible to clarify the boundary conditions through a property definition or through a special boundary demarcation re-establish boundary marks.

    The methods used are: (1) A literature review to collect background information, (2) A case study to summarize court cases and (3) A questionnaire study to collect opinions from cadastral surveyors.

    The result is summarized in two comparisons. Firstly between restoration of landmark and special boundary demarcation (which replaced restoration of landmark in a legislative change in 2010), which demonstrated that the change in the law is considered positive because special boundary demarcation gives a legal effect on the boundaries. Secondly between property definition and special boundary demarcation which demonstrated that the two procedures are similar to each other. One difference between the procedures is that special boundary demarcation only can be used when there are no uncertainties concerning the boundary. It also demonstrated that the cadastral procedure costs only can be distributed during property definition.

    The legal effect on the boundaries contributes with a certainty for the property owners and is also considered positive for the community development. No exact definition of what a legal uncertainty is, was found using the three methods. A definition should make it easier to know which cadastral procedure that should be used. A question to examine in future studies is the possibilities to distribute cadastral procedure costs even during special boundary demarcation. 

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    Fastighetsbestämning och särskild gränsutmärkning i Sverige
  • 147.
    Andersson, Victor
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Industrial economics.
    Pappersfria informationsflöden: En fallstudie om implementeringsprocessen2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Although computers have been around for a long time and are used more and more, the use of paper inoffices remains. One of the reasons is that there are not good enough digital tools to get rid of paper from work. In this qualitative case study, the office department of ABB Components is investigating on how the implementation processes for a paperless information flows can be introduced in ways that generate benefits of working digitally.

    The result of this study will be based on data collected from interviews and observations carriedout in the office. By identifying which processes using paper in the office, different tools have been developed to facilitate the implementation. The result of this study suggests that the implementation of a paperless information flows must be a well-planned change process where tools are developed to compensate for the earlier use of paper.

    With the introduction of paperless information flows, the use of consumables will decrease and the location it takes to store these papers will disappear. This leads to more cost-effective work and less waste paper. In order for this concept to lead to a more beneficial routine it needs to be redesigned for the implementation.

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    Pappersfria informationsflöden
  • 148.
    Andrée, Martin
    et al.
    Lantmäteriet.
    Larsson, Karolina
    KLM; Stockholms stad.
    Nordqvist Darell, Fanny
    Stockholms stad.
    Malm, Linus
    Tyréns.
    Tullberg, Odd
    WSP.
    Wallberg, Ann
    JM.
    Norsell, Johan
    NAI Svefa.
    Paasch, Jesper M.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Land management, GIS.
    Seipel, Stefan
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Computer science.
    Paulsson, Jenny
    Kungliga Tekniska Högskolan, Stockholm.
    Slutrapport för projektet Smart planering för byggande: Delprojekt 3 - BIM som informationsstöd för 3D fastighetsbildning2018Report (Other academic)
    Abstract [sv]

    Samhällsbyggnadsprocessen behöver utvecklas och bli smartare, öppnare och mer effektiv för ett ökat bostadsbyggande. En digitalisering av samhällsbyggnadsprocessen kan ge ett effektivare samarbete mellan kommun, fastighetsägare, byggherrar, medborgare, näringsliv och myndigheter.Vid bildande av tredimensionellt avgränsade fastigheter eller fastighetsutrymmen (3D-fastigheter) behöver gränsernas läge redovisas både verbalt och i kartor och ritningar, detsamma gäller berörda rättigheter. Det är idag ofta svårt att korrekt redovisa en 3D-volym med enbart dagens pappersritningar och även svårt att läsa en registerkarta i 2D med fastigheter och rättigheter beslutade i 3D. Beslutsunderlagen i fastighetsbildnings-processen behöver bli mer enhetliga och entydiga samt fastighetsinformationen behöver bli återanvändningsbar i hela samhällsbyggnadsprocessen.I detta projekt har vi studerat informationsbehovet i de olika tidpunkterna under fastighetsbildningsprocessen för 3D-fastigheter med fokus på vem som är ansvarig för att tillhandahålla informationsunderlag för att identifiera krav på utformning av 3D-modeller (t.ex BIM) och 3D-stöd för fastighetsbildning.Internationellt finns det ett stort intresse och många frågeställningar gällande samspelet mellan BIM och Fastighetsinformation; det är däremot ganska få fall som har identifierats där man har arbetat praktiskt med BIM i relation till redovisning av 3D-fastigheter.Projektethar även tittat på behov av visualisering och tillhandahållande av fastighetsinformation i 3D, hur informationen bör utformas för att kunna tolkas korrekt samt nyttjas vidare av andra aktörer i samhällsbyggnadsprocessen.Slutsatsen i projektetär att en framtida arbetsmodell där man i samband med myndighetsutövningen för fastighetsbildning samverkar med stöd av BIM och geografisk information i ärendehandläggningen kan ge stora effekter på både myndighetens effektivitet och i ärendeutövningen och för förståelsen av fastighetbildningsbeslutet hos samtliga intressenter i processen. För att det arbete som genomförts i denna utredning skall få genomslag i den dagliga verksamheten rekommenderar vibland annatatt de statliga och kommunala lantmäterimyndigheterna arbetar vidare med att utveckla arbetsprocessen och rekommendationerna för 3D-fastighetsbildning baserat på resultatet från detta projekt och redan i dagens modell efterfrågar att man i handläggningsprocessen kan arbeta BIM-baserat även om kommande beslutshandlingar under en övergångsperiod fortfarande kommer att vara baserade på ritningsbilagor i 2D.

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    fulltext
  • 149.
    Angele, Kristian
    et al.
    Vattenfall Research & Development AB, Älvkarleby, Sweden.
    Cehlin, Mathias
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy engineering. Vattenfall Research & Development AB, Älvkarleby, Sweden.
    Högström, Carl-Maikel
    Vattenfall Research & Development AB, Älvkarleby, Sweden.
    Odemark, Ylva
    Vattenfall Research & Development AB, Älvkarleby, Sweden.
    Henriksson, Mats
    Vattenfall Research & Development AB, Älvkarleby, Sweden.
    Tinoco, Hernan
    Forsmarks Kraftgrupp AB, Östhammar, Sweden.
    Lindqvist, Hans
    Forsmarks Kraftgrupp AB, Östhammar, Sweden.
    Hemström, Bengt
    Vattenfall Research & Development AB, Älvkarleby, Sweden.
    Flow Mixing Inside a Control-Rod Guide Tube: Part 2—Experimental Tests and CFD-Simulations2010In: 18th International Conference on Nuclear Engineering: Volume 4, Parts A and B, 2010, p. 655-663Conference paper (Refereed)
    Abstract [en]

    Alarge number of control rod cracks were detected during therefuelling outage of the twin reactors Oskarshamn 3 and Forsmark3 in the fall of 2008. The extensive damage investigationfinally lead to the restart of both reactors at theend of 2008 under the condition that further studies wouldbe conducted in order to clarify all remaining matters. Also,all control rods were inserted 14% in order to locatethe welding region of the control rod stem away fromthe thermal mixing region of the flow. Unfortunately, this measureled to new cracks a few months later due toa combination of surface finish of the new stems andthe changed flow conditions after the partial insertion of thecontrol rods. The experimental evidence reported here shows an increasein the extension of the mixing region and in theintensity of the thermal fluctuations. As a part of thecomplementary work associated with the restart of the reactors, andto verify the CFD simulations, experimental work of the flowin the annular region formed by the guide tube andcontrol rod stem was carried out. Two full-scale setups weredeveloped, one in a Plexiglass model at atmospheric conditions (inorder to be able to visualize the mixing process) andone in a steel model to allow for a highertemperature difference and heating of the control rod guide tube.The experimental results corroborate the general information obtained through CFDsimulations, namely that the mixing region between the cold crud-removalflow and warm by-pass flow is perturbed by flow structurescoming from above. The process is characterized by low frequent,high amplitude temperature fluctuations. The process is basically hydrodynamic, causedby the downward transport of flow structures originated at theupper bypass inlets. The damping thermal effects through buoyancy isof secondary importance, as also the scaling analysis shows, howevera slight damping of the temperature fluctuations can be seendue to natural convection due to a pre-heating of thecold crud-removal flow. The comparison between numerical and experimental resultsshows a rather good agreement, indicating that experiments with plantconditions are not necessary since, through the existing scaling lawsand CFD-calculations, the obtained results may be extrapolated to plantconditions. The problem of conjugate heat transfer has not yetbeen addressed experimentally since complex and difficult measurements of theheat transfer have to be carried out. This type ofmeasurements constitutes one of the main challenges to be dealtwith in the future work.

  • 150.
    Angele, Kristian
    et al.
    Vattenfall Research & Development AB, Älvkarleby, Sweden.
    Odemark, Ylva
    Vattenfall Research & Development AB, Älvkarleby, Sweden.
    Cehlin, Mathias
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Energy engineering. Vattenfall Research & Development AB, Älvkarleby, Sweden.
    Hemström, Bengt
    Vattenfall Research & Development AB, Älvkarleby, Sweden.
    Högström, Carl-Maikel
    Vattenfall Research & Development AB, Älvkarleby, Sweden.
    Henriksson, Mats
    Vattenfall Research & Development AB, Älvkarleby, Sweden.
    Tinoco, Hernan
    Forsmarks Kraftgrupp AB, Östhammar, Sweden.
    Lindqvist, Hans
    Forsmarks Kraftgrupp AB, Östhammar, Sweden.
    Flow mixing inside a control-rod guide tube: Experimental tests and CFD simulations2011In: Nuclear Engineering and Design, ISSN 0029-5493, E-ISSN 1872-759X, Vol. 241, no 12, p. 4803-4812Article in journal (Refereed)
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