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  • 1.
    Amin, Hadi
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    Sjöberg, Lars
    Division of Geodesy and satellite positioning, KTH.
    Bagherbandi, Mohammad
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    A global vertical datum defined by the conventional geoid potential and the Earth ellipsoid parameters2019In: Journal of Geodesy, ISSN 0949-7714, E-ISSN 1432-1394, Vol. 93, no 10, p. 1943-1961Article in journal (Refereed)
    Abstract [en]

    The geoid, according to the classical Gauss–Listing definition, is, among infinite equipotential surfaces of the Earth’s gravity field, the equipotential surface that in a least squares sense best fits the undisturbed mean sea level. This equipotential surface, except for its zero-degree harmonic, can be characterized using the Earth’s global gravity models (GGM). Although, nowadays, satellite altimetry technique provides the absolute geoid height over oceans that can be used to calibrate the unknown zero-degree harmonic of the gravimetric geoid models, this technique cannot be utilized to estimate the geometric parameters of the mean Earth ellipsoid (MEE). The main objective of this study is to perform a joint estimation of W0, which defines the zero datum of vertical coordinates, and the MEE parameters relying on a new approach and on the newest gravity field, mean sea surface and mean dynamic topography models. As our approach utilizes both satellite altimetry observations and a GGM model, we consider different aspects of the input data to evaluate the sensitivity of our estimations to the input data. Unlike previous studies, our results show that it is not sufficient to use only the satellite-component of a quasi-stationary GGM to estimate W0. In addition, our results confirm a high sensitivity of the applied approach to the altimetry-based geoid heights, i.e., mean sea surface and mean dynamic topography models. Moreover, as W0 should be considered a quasi-stationary parameter, we quantify the effect of time-dependent Earth’s gravity field changes as well as the time-dependent sea level changes on the estimation of W0. Our computations resulted in the geoid potential W0 = 62636848.102 ± 0.004 m2 s−2 and the semi-major and minor axes of the MEE, a = 6378137.678 ± 0.0003 m and b = 6356752.964 ± 0.0005 m, which are 0.678 and 0.650 m larger than those axes of GRS80 reference ellipsoid, respectively. Moreover, a new estimation for the geocentric gravitational constant was obtained as GM = (398600460.55 ± 0.03) × 106 m3 s−2.

  • 2.
    Aslani, Mohammad
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Computer Science.
    Computational and spatial analyses of rooftops for urban solar energy planning2022Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In cities where land availability is limited, rooftop photovoltaic panels (RPVs) offer high potential for satisfying concentrated urban energy demand by using only rooftop areas. However, accurate estimation of RPVs potential in relation to their spatial distribution is indispensable for successful energy planning. Classification, plane segmentation, and spatial analysis are three important aspects in this context. Classification enables extracting rooftops and allows for estimating solar energy potential based on existing training samples. Plane segmentation helps to characterize rooftops by extracting their planar patches. Additionally, spatial analyses enable the identification of rooftop utilizable areas for placing RPVs. This dissertation aims to address some issues associated with these three aspects, particularly (a) training support vector machines (SVMs) in large datasets, (b) plane segmentation of rooftops, and (c) identification of utilizable areas for RPVs. SVMs are among the most potent classifiers and have a solid theoretical foundation. However, they have high time complexity in their training phase, making them inapplicable in large datasets. Two new instance selection methods were proposed to accelerate the training phase of SVMs. The methods are based on locality-sensitive hashing and are capable of handling large datasets. As an application, they were incorporated into a rooftop extraction procedure, followed by plane segmentation. Plane segmentation of rooftops for the purpose of solar energy potential estimation should have a low risk of overlooking superstructures, which play an essential role in the placement of RPVs. Two new methods for plane segmentation in high-resolution digital surface models were thus developed. They have an acceptable level of accuracy and can successfully extract planar segments by considering superstructures. Not all areas of planar segments are utilizable for mounting RPVs, and some factors may further limit their useability. Two spatial methods for identifying RPV-utilizable areas were developed in this realm. They scrutinize extracted planar segments by considering panel installation regulations, solar irradiation, roof geometry, and occlusion, which are necessary for a realistic assessment of RPVs potential. All six proposed methods in this thesis were thoroughly evaluated, and the experimental results show that they can successfully achieve the objectives for which they were designed.

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  • 3.
    Aslani, Mohammad
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Computer Science.
    Seipel, Stefan
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Computer Science. Uppsala universitet.
    A Spatially Detailed Approach to the Assessment of Rooftop Solar Energy Potential based on LiDAR Data2022In: Proceedings of the 8th International Conference on Geographical Information Systems Theory, Applications and Management - GISTAM, ScitePress , 2022, p. 56-63Conference paper (Refereed)
    Abstract [en]

    Rooftop solar energy has long been regarded as a promising solution to cities’ growing energy demand and environmental problems. A reliable estimate of rooftop solar energy facilitates the deployment of photovoltaics and helps formulate renewable-related policies. This reliable estimate underpins the necessity of accurately pinpointing the areas utilizable for mounting photovoltaics. The size, shape, and superstructures of rooftops as well as shadow effects are the important factors that have a considerable impact on utilizable areas. In this study, the utilizable areas and solar energy potential of rooftops are estimated by considering the mentioned factors using a three-step methodology. The first step involves training PointNet++, a deep network for object detection in point clouds, to recognize rooftops in LiDAR data. Second, planar segments of rooftops are extracted using clustering. Finally, areas that receive sufficient solar irradiation, have an appropriate size, and fulfill photovoltaic installation requirements are identified using morphological operations and predefined thresholds. The obtained results show high accuracy for rooftop extraction (93%) and plane segmentation (99%). Moreover, the spatially detailed analysis indicates that 17% of rooftop areas are usable for photovoltaics.

  • 4.
    Bagherbandi, Mohammad
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences. KTH.
    Amin, Hadi
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences. Department of Computer and Spatial Sciences University of Gävle Gävle Sweden.
    Wang, Linsong
    China University of Geosciences; GFZ German Research Centre for Geosciences, Telegrafenberg, Germany.
    Shirazian, Masoud
    Shahid Rajaee Teacher Training University, Tehran, Iran.
    Mantle Viscosity Derived From Geoid and Different Land Uplift Data in Greenland2022In: Journal of Geophysical Research - Solid Earth, ISSN 2169-9313, E-ISSN 2169-9356, Vol. 127, no 8, article id e2021JB023351Article in journal (Refereed)
    Abstract [en]

    The Earth's mass redistribution due to deglaciation and recent ice sheet melting causes changes in the Earth's gravity field and vertical land motion in Greenland. The changes are because of ongoing mass redistribution and related elastic (on a short time scale) and viscoelastic (on time scales of a few thousands of years) responses. These signatures can be used to determine the mantle viscosity. In this study, we infer the mantle viscosity associated with the glacial isostatic adjustment (GIA) and long-wavelength geoid beneath the Greenland lithosphere. The viscosity is determined based on a spatio-spectral analysis of the Earth's gravity field and the land uplift rate in order to find the GIA-related gravity field. We used different land uplift data, that is, the vertical land motions obtained by the Greenland Global Positioning System (GPS) Network (GNET), gravity recovery and climate experiment (GRACE) and glacial isostatic adjustment (GIA) data, and also combined them using the Kalman filtering technique. Using different land uplift rates, one can obtain different GIA-related gravity fields. As shown in this study, the mantle viscosities of 1.9 × 1022 Pa s and 7.8 × 1021 Pa s for a depth of 200–700 km are obtained using ICE-6G (VM5a) model and the combined land uplift model, respectively, and the GIA-related gravity potential signal

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  • 5.
    Bagherbandi, Mohammad
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Land management, GIS. KTH Royal Institute of Technology, Stockholm, Sweden.
    Bai, Yongliang
    School of Geosciences, China University of Petroleum (East China), Qingdao, China.
    Sjöberg, Lars
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Tenzer, Robert
    NTIS - New Technologies for the Information Society, Faculty of Applied Sciences, University of West Bohemia, Plzeň, Czechia.
    Abrehdary, Majid
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Miranda, Silvia
    Departamento de Geofísica y Astronomía, FCEFN Universidad Nacional de San Juan, San Juan, Argentina.
    Sanchez, Juan M. Alcacer
    Departamento de Geofísica y Astronomía, FCEFN Universidad Nacional de San Juan, San Juan, Argentina.
    Effect of the lithospheric thermal state on the Moho interface: a case study in South America2017In: Journal of South American Earth Sciences, ISSN 0895-9811, E-ISSN 1873-0647, Vol. 76, p. 198-207Article in journal (Refereed)
    Abstract [en]

    Gravimetric methods applied for Moho recovery in areas with sparse and irregular distribution of seismic data often assume only a constant crustal density. Results of latest studies, however, indicate that corrections for crustal density heterogeneities could improve the gravimetric result, especially in regions with a complex geologic/tectonic structure. Moreover, the isostatic mass balance reflects also the density structure within the lithosphere. The gravimetric methods should therefore incorporate an additional correction for the lithospheric mantle as well as deeper mantle density heterogeneities. Following this principle, we solve the Vening Meinesz-Moritz (VMM) inverse problem of isostasy constrained by seismic data to determine the Moho depth of the South American tectonic plate including surrounding oceans, while taking into consideration the crustal and mantle density heterogeneities. Our numerical result confirms that contribution of sediments significantly modifies the estimation of the Moho geometry especially along the continental margins with large sediment deposits. To account for the mantle density heterogeneities we develop and apply a method in order to correct the Moho geometry for the contribution of the lithospheric thermal state (i.e., the lithospheric thermal-pressure correction). In addition, the misfit between the isostatic and seismic Moho models, attributed mainly to deep mantle density heterogeneities and other geophysical phenomena, is corrected for by applying the non-isostatic correction. The results reveal that the application of the lithospheric thermal-pressure correction improves the RMS fit of the VMM gravimetric Moho solution to the CRUST1.0 (improves ∼ 1.9 km) and GEMMA (∼1.1 km) models and the point-wise seismic data (∼0.7 km) in South America.

  • 6.
    Bagherbandi, Mohammad
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Sjöberg, Lars E.
    Royal Institute of Technology (KTH), Stockholm, Sweden.
    Improving gravimetric–isostatic models of crustal depth by correcting for non-isostatic effects and using CRUST2.02013In: Earth-Science Reviews, ISSN 0012-8252, E-ISSN 1872-6828, Vol. 117, p. 29-39Article, review/survey (Refereed)
    Abstract [en]

    The principle of isostasy is important in different fields of geosciences. Using an isostatic hypothesis for estimating the crustal thickness suffers from the more or less incomplete isostatic model and that the observed gravity anomaly is not only generated by the topographic/isostatic signal but also by non-isostatic effects (NIEs). In most applications of isostatic models the NIEs are disregarded. In this paper, we study how some isostatic models related with Vening Meinez's isostatic hypothesis can be improved by considering the NIE. The isostatic gravity anomaly needs a correction for the NIEs, which varies from as much as 494 mGal to − 308 mGal. The result shows that by adding this correction the global crustal thickness estimate improves about 50% with respect to the global model CRUST2.0, i.e. the root mean square differences of the crustal thickness of the best Vening Meinesz type and CRUST2.0 models are 6.9 and 3.2 km before and after improvement, respectively. As a result, a new global model of crustal thickness using Vening Meinesz and CRUST2.0 models is generated. A comparison with an independent African crustal depth model shows an improvement of the new model by 6.8 km vs. CRUST2.0 (i.e. rms differences of 3.0 and 9.8 km, respectively). A comparison between oceanic lithosphere age and the NIEs is discussed in this study, too. One application of this study can be to improve crustal depth in areas where CRUST2.0 data are sparse and bad and to densify the resolution vs. the CRUST2.0 model. Other applications can be used to infer the viscosity of the mantle from the NIEs signal to study various locations around the Earth for understanding complete, over- and under-compensations of the topography.

  • 7.
    Bagherbandi, Mohammad
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute. KTH, Geodesy & Geoinformatics, Stockholm, Sweden.
    Tenzer, Robert
    School of Geodesy and Geomatics, Wuhan University, Wuhan, China.
    Geoid-to-Quasigeoid Separation Computed Using the GRACE/GOCE Global Geopotential Model GOCO02S: A Case Study of Himalayas and Tibet2013In: Terrestrial, Atmospheric and Oceanic Science, ISSN 1017-0839, E-ISSN 2223-8964, Vol. 24, no 1, p. 59-68Article in journal (Refereed)
    Abstract [en]

    The geoid-to-quasigeoid correction has been traditionally computed approximately as a function of the planar Bouguer gravity anomaly and the topographic height. Recent numerical studies based on newly developed theoretical models, however, indicate that the computation of this correction using the approximate formula yields large errors especially in mountainous regions with computation points at high elevations. In this study we investigate these approximation errors at the study area which comprises Himalayas and Tibet where this correction reaches global maxima. Since the GPS-leveling and terrestrial gravity datasets in this part of the world are not (freely) available, global gravitational models (GGMs) are used to compute this correction utilizing the expressions for a spherical harmonic analysis of the gravity field. The computation of this correction can be done using the GGM coefficients taken from the Earth Gravitational Model 2008 (EGM08) complete to degree 2160 of spherical harmonics. The recent studies based on a regional accuracy assessment of GGMs have shown that the combined GRACE/GOCE solutions provide a substantial improvement of the Earth’s gravity field at medium wavelengths of spherical harmonics compared to EGM08. We address this aspect in numerical analysis by comparing the gravity field quantities computed using the satellite-only combined GRACE/GOCE model GOCO02S against the EGM08 results. The numerical results reveal that errors in the geoid-to-quasigeoid correction computed using the approximate formula can reach as much as ~1.5 m. We also demonstrate that the expected improvement of the GOCO02S gravity field quantities at medium wavelengths (within the frequency band approximately between 100 and 250) compared to EGM08 is as much as ±60 mGal and ±0.2 m in terms of gravity anomalies and geoid/quasigeoid heights respectively.

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  • 8.
    Bagherbandi, Mohammad
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Tenzer, Robert
    Wuhan University, China.
    Sjöberg, Lars
    Royal Institute of Technology (KTH), Stockholm, Sweden.
    Novak, Pavel
    University of West Bohemia, Plzen, Czech Republic.
    Improved global crustal thickness modeling based on the VMM isostatic model and non-isostatic gravity correction2013In: Journal of Geodynamics, ISSN 0264-3707, E-ISSN 1879-1670, Vol. 66, p. 25-37Article in journal (Refereed)
    Abstract [en]

    In classical isostatic models for a gravimetric recovery of the Moho parameters (i.e., Moho depths and density contrast) the isostatic gravity anomalies are usually defined based on the assumption that the topographic mass surplus and the ocean mass deficiency are compensated within the Earth’s crust. As acquired in this study, this assumption yields large disagreements between isostatic and seismic Moho models. To assess the effects not accounted for in classical isostatic models, we conduct a number of numerical experiments using available global gravity and crustal structure models. First, we compute the gravitational contributions of mass density contrasts due to ice and sediments, and subsequently evaluate respective changes in the Moho geometry. Residual differences between the gravimetric and seismic Moho models are then used to predict a remaining non-isostatic gravity signal, which is mainly attributed to unmodeled density structures and other geophysical phenomena. We utilize three recently developed computational schemes in our numerical studies. The apparatus of spherical harmonic analysis and synthesis is applied in forward modeling of the isostatic gravity disturbances. The Moho depths are estimated globally on a 1 arc-deg equiangular grid by solving the Vening-Meinesz Moritz inverse problem of isostasy. The same estimation model is applied to evaluate the differences between the isostatic and seismic models. We demonstrate that the application of the ice and sediment density contrasts stripping gravity corrections is essential for a more accurate determination of the Moho geometry. We also show that the application of the additional non-isostatic correction further improves the agreement between the Moho models derived based on gravity and seismic data. Our conclusions are based on comparing the gravimetric results with the CRUST2.0 global crustal model compiled using results of seismic surveys.

  • 9.
    Bagherbandi, Mohammad
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute. KTH.
    Tenzer, Robert
    Royal Institute of Technology (KTH), Stockholm, Sweden .
    Sjöberg, L.E.
    Wuhan University, Wuhan, China .
    Moho depth uncertainties in the Vening-Meinesz Moritz inverse problem of isostasy2014In: Studia Geophysica et Geodaetica, ISSN 0039-3169, E-ISSN 1573-1626, Vol. 58, no 2, p. 227-248Article in journal (Refereed)
    Abstract [en]

    We formulate an error propagation model based on solving the Vening Meinesz-Moritz (VMM) inverse problem of isostasy. The system ofobservation equations in the VMM model defines the relation between theisostatic gravity data and the Moho depth  by means of a second-order Fredholm integralequation of the first kind. The corresponding error model (derived in aspectral domain) functionally relates the Moho depth errors with the commissionerrors of used gravity and topographic/bathymetric models. The error model alsoincorporates the non-isostatic bias which describesthe disagreement, mainly of systematic nature, between the isostatic andseismic models. The error analysis is conducted at the study area of theTibetan Plateau and Himalayas with the world largest crustal thickness. TheMoho depth uncertainties due to errors of the currently available globalgravity and topographic models are estimated to be typically up to 1-2 km,provided that the GOCE gravity gradient observables improved themedium-wavelength gravity spectra. The errors due to disregarding sedimentarybasins can locally exceed ~2 km. The largest errors (which cause a systematic bias betweenisostatic and seismic models) are attributed to unmodeled mantleheterogeneities (including thecore-mantle boundary) and other geophysical processes. These errors aremostly less than 2 km under significant orogens (Himalayas, Ural), but canreach up to ~10 km under the oceanic crust.

  • 10.
    Bekele, Yared
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    GIS Based Factor Identification for the Change in Occurrence of Genista pilosa: a Case Study in Southern Sweden2012Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study has the objective of identifying the possible environmental constraints that has role for the continuous loss of heathland plant Genista pilosa. The study has assessed different environmental settings where the plant occurs by way of overlaying analysis based on multiple spatial data sets. Thereafter empirical change detection analyses on the land use of the study area have been performed on the GIS environment by combining temporal based remotely sensed spatial data. The result was then analyzed using land use dynamicity model and the rates of change on each land use type are identified. Expansion of human activity, especially the spreading of agricultural land and urbanization, is found to be the most determinant factor for the dramatic loss of the plant. Finally serious attention for the protection of the plant is recommended by mentioning the possible problem that would occur due to a loss of biodiversity.

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    GIS-Based Factor Identification for the Change in Occurrence of Genista pilosa a Case Study in Southern Sweden
  • 11.
    Billenberg, Mathias
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    Investigation of above-ground biomass with terrestrial laser scanning: A case study of Valls Hage in Gävle2023Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The thesis investigates above-ground biomass (AGB) with terrestrial laser scanning (TLS) for estimating AGB in a study area in Valls Hage, Gävle. The study used TLS for field measurements to collect highly detailed point clouds of two tree species for AGB estimation and comparison against validation data. TLS-derived data were validated using a non-destructive method involving direct field measurements using tape measures and a Trimble SX12 for extracting diameter at breast height (DBH), tree height, and crown diameter. Wood density was obtained from the literature. Data processing for segmentation, filtering, and generation of the quantitative structure model (QSM) was performed by using SimpleForest tool in Computree software. A statistical analysis was performed using linear regression, and AGB was estimated using QSM-derived volume multiplied by wood density. The finding in the results for the comparison of AGB estimation between TLS QSM and field validation from DBH-based tree-specific allometric equation had an RMSE of 154 kg, with a near-perfect agreement of 0.997 %, and RMSE of 189 kg, with the agreement of 0.990% for TLS QSM and TLS validation DBH-based tree specific equation. The comparison between TLS-derived DBH and field validation was accurate, leaving with insignificant differences, while the tree height had noticeable differences, and crown diameter had relatively low differences. The challenges during data processing were highlighted and the importance of TLS data for accurate AGB estimation, with the potential for refinement and integrating internal tree structure information to improve allometric models for future studies.

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  • 12.
    Carpenter, Angela
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production.
    Lozano, Rodrigo
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production.
    Introduction, chapter summary, and conclusions from the book2020In: European port cities in transition: Moving towards more sustainable sea transport hubs, Springer, 2020, p. 1-17Chapter in book (Other academic)
  • 13.
    Carpenter, Angela
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production.
    Lozano, Rodrigo
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production.
    Proposing a framework for anchoring sustainability relationships between ports and cities2020In: European port cities in transition: Moving towards more sustainable sea transport hubs, Springer, 2020, p. 37-51Chapter in book (Other academic)
  • 14.
    Eklundh, Lars
    et al.
    Lunds universitet.
    Ågren, Jonas
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    Olsson, Håkan
    Sveriges Lantbruksuniversitet.
    Harrie, Lars
    Lunds universitet.
    Klang, Dan
    Insamling av geografiska data2020In: Geografisk informationsbehandling: Teori, metoder och tillämpningar / [ed] Lars Harrie, Studentlitteratur AB, 2020, 7, p. 85-126Chapter in book (Other (popular science, discussion, etc.))
    Abstract [sv]

    Det här kapitlet fokuserar på att förklara de grundläggande principerna för insamling av geografiska data, och vi lägger tonvikten på fjärranalys och geodetiska metoder. Fjärranalys innefattar olika tekniker som fotogrammetri, laserskanning och analys av bilder från mark, flyg och satelliter. Geodetiska datainsamling används för att mäta in koordinater för objekt på marken och innefattar satellitbaserade tekniker såväl som användning av fältinstrument. Olika tekniker, avseende både fjärranalys och geodesi, används i olika situationer beroende på krav på noggrannhet och innehåll, och kompletterar därför varandra. Vi börjar med att beskriva satellitfjärranalys som kan täcka stora områden med relativt begränsad detaljeringsgrad, beskriver sedan flygbilder och laserskanning där detaljnivån ökar, för att till sist beskriva de geodetiska metoderna för noggranna mätningar på marknivå.

  • 15.
    Engfeldt, Andreas
    et al.
    Lantmäteriet.
    Olsson, Per-Anders
    Lantmäteriet.
    Steffen, Holger
    Lantmäteriet.
    Lidberg, Martin
    Lantmäteriet.
    Ågren, Jonas
    Lantmäteriet.
    Sekowski, Marcin
    Institute of Geodesy and Cartography, Poland.
    Krynski, Jan
    Institute of Geodesy and Cartography, Poland.
    Bryskhe, Henrik
    Lantmäteriet.
    Nielsen, Jens Emil
    Danish Technical University, Denmark.
    Strykowski, Gabriel
    Danish Technical University, Denmark.
    RG 2000 – the New Gravity Reference Frame of Sweden2019In: Geophysica, ISSN 0367-4231, E-ISSN 2324-0741, Vol. 54, no 1, p. 69-92Article in journal (Refereed)
    Abstract [en]

    The increased need for improved geoid models for Global Navigation Satellite Systems (GNSS) height determination calls for additional gravity observations and quality assurance of existing data. In this perspective, a modern gravity system and the renovation of an already existing high order gravity network is considered as a moderate strategic investment which provides a firm foundation for further activities. Here the new gravity reference frame RG 2000 for Sweden is presented. RG 2000 is realized by absolute gravity observations at 109 stations. The absolute points are connected via old and new relative gravity observations, including another 216 points. Points and observations have been chosen so that good overlap with the older Swedish reference frames, RG 62 and RG 82, is achieved, allowing to evaluate the older frames and transformations between them. RG 2000 is based on a zero permanent tide system with epoch 2000.

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  • 16.
    Findler, Florian
    et al.
    Vienna University of Economics and Business, Vienna, Austria.
    Schönherr, Norma
    Vienna University of Economics and Business, Vienna, Austria.
    Lozano, Rodrigo
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production.
    Reider, Daniela
    Vienna University of Economics and Business, Vienna, Austria.
    Martinuzzi, André
    Vienna University of Economics and Business, Vienna, Austria.
    The impacts of higher education institutions on sustainable development: a review and conceptualization2019In: International Journal of Sustainability in Higher Education, ISSN 1467-6370, E-ISSN 1758-6739, Vol. 20, no 1, p. 23-38Article, review/survey (Refereed)
    Abstract [en]

    Purpose

    This paper aims to conceptualize impacts of higher education institutions (HEIs) on sustainable development (SD), complementing previous literature reviews by broadening the perspective from what HEIs do in pursuit of SD to how these activities impact society, the environment and the economy.

    Design/methodology/approach

    The paper provides a systematic literature review of peer-reviewed journal articles published between 2005 and 2017. Inductive content analysis was applied to identify major themes and impact areas addressed in the literature to develop a conceptual framework detailing the relationship between HEIs’ activities and their impacts on SD.

    Findings

    The paper identifies six impact areas where direct and indirect impacts of HEIs on SD may occur. The findings indicate a strong focus on case studies dealing with specific projects and a lack of studies analyzing impacts from a more holistic perspective.

    Practical implications

    This systematic literature review enables decision-makers in HEIs, researchers and educators to better understand how their activities may affect society, the environment and the economy, and it provides a solid foundation to tackle these impacts.

    Social implications

    The review highlights that HEIs have an inherent responsibility to make societies more sustainable. HEIs must embed SD into their systems while considering their impacts on society.

    Originality/value

    This paper provides a holistic conceptualization of HEIs’ impacts on SD. The conceptual framework can be useful for future research that attempts to analyze HEIs’ impacts on SD from a holistic perspective.

  • 17.
    Fobbe, Lea
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production.
    Lozano, Rodrigo
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production.
    Carpenter, Angela
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production.
    Proposing a holistic framework to assess sustainability performance in seaports2020In: European port cities in transition: Moving towards more sustainable sea transport hubs, Springer, 2020, p. 149-168Chapter in book (Other academic)
  • 18.
    Gruber, Thomas
    et al.
    Technical University of Munich, Institute of Astronomical and Physical Geodesy, Germany.
    Ågren, Jonas
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences. Lantmäteriet.
    Angermann, Detlef
    Technical University of Munich, Deutsches Geodätisches Forschungsinstitut, Germany.
    Ellmann, Artu
    Tallinn University of Technology, School of Engineering, Estonia.
    Gisinger, Christoph
    German Aerospace Center, Remote Sensing Technology, Germany.
    Nastula, Jolanta
    Centrum Badań Kosmicznych, Polskiej Akademii Nauk, Poland.
    Poutanen, Markku
    Finnish Geospatial Research Institute, Finland.
    Schlaak, Marius
    Technical University of Munich, Germany.
    Nilfouroushan, Faramarz
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences. Lantmäteriet.
    Varbla, Sander
    Tallinn University of Technology, School of Engineering, Estonia.
    Zdunek, Ryszard
    Centrum Badań Kosmicznych, Polskiej Akademii Nauk, Poland.
    Marila, Simo
    Finnish Geospatial Research Institute, Finland.
    Engfeldt, Andreas
    Lantmäteriet, Swedish Mapping, Cadastral and Land Registration Authority, Sweden.
    Saari, Timo
    Finnish Geospatial Research Institute, Finland.
    Świątek, Anna
    Centrum Badań Kosmicznych, Polskiej Akademii Nauk, Poland.
    Geodetic SAR for Height System Unification and Sea Level Research - Observation Concept and Results in the Baltic Sea2022Conference paper (Refereed)
    Abstract [en]

    Traditionally, sea level is observed at tide gauge stations, which usually also serve as height reference stations for national leveling networks and therefore define a height system of a country. Thus, sea level research across countries is closely linked to height system unification and needs to be regarded jointly. One of the main deficiencies to use tide gauge data for geodetic sea level research and height systems unification is that only a few stations are connected to permanent GNSS receivers next to the tide gauge in order to systematically observe vertical land motion. As a new observation technique, absolute positioning by SAR using active transponders on ground can fill this gap by systematically observing time series of geometric heights at tide gauge stations. By additionally knowing the tide gauge geoid heights in a global height reference frame, one can finally obtain absolute sea level heights at each tide gauge. With this information the impact of climate change on the sea level can be quantified in an absolute manner and height systems can be connected across the oceans.The paper presents the results of a project, which was conducted in the years 2019 to 2021 in the frame of ESA´s Baltic+ initiative. Within this project a test network of electronic corner reflectors (ECR) as targets for Sentinel-1 was realized in the Baltic Sea area. The ECR locations were either co-located with tide gauges or with permanent GNSS stations in order to observe systematically the ellipsoidal heights of the tide gauges and possibly also any vertical land motion at the stations. Data for the year 2020 were collected at 10 stations in Estonia, Finland, Poland and Sweden and jointly analyzed with GNSS data, tide gauge records and regional geoid height estimates. The obtained results are promising, but also exhibit some problems related to the ECR´s and their performance. At co-located GNSS stations the estimated ellipsoidal heights agree in a range between about 2 and 50 cm between both observation systems. From the results it could be identified that most likely variable systematic electronic instrument delays of the ECR´s are the main reason for these differences and that each instrument needs to be calibrated individually. Nevertheless, the project provides a valuable data set, which offers the possibility to enhance methods and procedures in order to develop the geodetic SAR positioning technique towards operability. All data and reports are accessible at the following web site: https://www.asg.ed.tum.de/iapg/baltic/

  • 19.
    Håkansson, Timmie
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    Lind, Rebecca
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    Riskreducering av naturolyckor med hjälp av spatial multikriterieanalys: En fallstudie över Gävle kommuns omvandling av industriområdet Näringen utifrån kommun- respektive försäkringsperspektiv2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The context of this study came from Gävle municipality's planned transformation of the coastal district of Näringen, where many natural geographical and geotechnical challenges are identified. These challenges are expected to be exacerbated by climate change, but also to have a greater impact on low-lying areas and areas close to the sea. On the other hand, an economic gain is identified from the exploitation of land close to the center. The upcoming transformation of the district includes that 6,000 new homes and 450,000 square meters of new businesses will be added according to an agreement with the Swedish state. Increased financial burden for the insurance companies in connection with climate change and natural phenomena forces the insurance companies to review what can be insured in the future. A conflict was identified between the municipality's and the state's definition of sustainability, in comparison with the insurance companies' view of what is sustainable and sustainable in the long term. The purpose of the study was to answer the research question How can the transformation of Näringen be designed through risk reduction to reduce exposure and vulnerability and at the same time increase the district's resilience? To answer the question, methods have used spatial multi-criteria analysis with hazard maps, and design based on the results of the multi-criteria analysis to create a modelled proposal that presents a new layout of the district, which meets the agreement's requirements for housing and square meters, in addition to that the placement of the settlement is made to the highest degree possible, in areas where the exposure to various risks is lower. 

    The results of the study aim to show differences in standpoints. As part of the risk reduction strategy, high-risk areas were classified as blue-green infrastructure for those areas where conventional land use, such as development for housing and businesses, was not deemed appropriate due to the high-risk values in these areas. Based on the results of these maps, a 3D- model was created with the aim of creating an educational tool. The 3D- modeling also contributes to a higher understanding of how, according to the study, unsuitable land or beach protection can be transformed into attractive green areas that offer recreation, infiltration of stormwater and that increase biodiversity. The results of the study offer easy-to-understand interpretations of the underlying natural geographical and geotechnical risks, which even the general public can take part in and interpret. A recurring element in the results of the study is that large, protected areas that are covered by beach protection (strandskydd), also cover the areas that have the highest risk values. 

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  • 20.
    Jabbari, Mona
    et al.
    CitUpia AB.
    Ahmadi, Zahra
    University of Gävle, Faculty of Education and Business Studies, Department of Business and Economic Studies, Business administration.
    Ramos, Rui
    Urban and Regional Planning, Department of Civil Engineering, University of Minho, 4710-057 Braga, Portugal.
    Defining a digital system for the pedestrian network as a conceptual implementation framework2022In: Sustainability, E-ISSN 2071-1050, Vol. 14, no 5, article id 528Article in journal (Refereed)
    Abstract [en]

    In cities today, the digitalization of mobility is one of the most crucial tools that link each single mobility service providers (e.g., ride sharing, public transportation, air travel, etc.) to users. Based on the smart pedestrian network model, the purpose of this study is to initially provide the requirements towards the digitalization of a pedestrian network model and subsequently to draft an institutional framework towards the effective implementation and management of pedestrian mobility that will develop/create a pedestrian network as a new structure in the city. The methodology is applied in three phases, with three separate approaches: “desk approach” for a data gathering standard that is knowledge-based and connected to walkability; a “digitalization approach” for citizen and stakeholder participation in policy co-creation; and a “business approach”. A business approach is defined as a set of operations that takes one or more types of input and produces a customer-valued outcome. In this case, customers are citizens and the business approach by applying a digital system is assessing policies and finding/defining an optimized combination of shared applicable/effective policies to implement the pedestrian network. By boosting an innovative linkage of these three phases, digitalization of the pedestrian network has great potential to improve the walkability planning process and therefore to create more sustainable and livable urban spaces.

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  • 21.
    Jiang, Bin
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    Spatial Heterogeneity, Scale, Data Character, and Sustainable Transport in the Big Data Era2019In: DATA ANALYTICS: PAVING THE WAY TO SUSTAINABLE URBAN MOBILITY, 2019, Vol. 879, p. 730-736Conference paper (Refereed)
    Abstract [en]

    I have advocated and argued for a paradigm shift from Tobler's law to scaling law, from Euclidean geometry to fractal geometry, from Gaussian statistics to Paretian statistics, and - more importantly - from Descartes' mechanistic thinking to Alexander's organic thinking. Fractal geometry falls under the third definition of fractal given by Bin Jiang - that is, a set or pattern is fractal if the scaling of far more small things than large ones recurs multiple times - rather than under the second definition of fractal by Benoit Mandelbrot, which requires a power law between scales and details. The new fractal geometry is more towards Christopher Alexander's living geometry, not only for understanding complexity, but also for creating complex or living structure. This short paper attempts to clarify why the paradigm shift is essential and to elaborate on several concepts, including spatial heterogeneity (scaling law), scale (or the fourth meaning of scale), data character (in contrast to data quality), and sustainable transport in the big data era.

  • 22.
    Jiang, Bin
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    de Rijke, Chris
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    Living Images: A Recursive Approach to Computing the Structural Beauty of Images or the Livingness of Space2023In: Annals of the American Association of Geographers, ISSN 2469-4452, E-ISSN 2469-4460, Vol. 113, no 6, p. 1329-1347Article in journal (Refereed)
    Abstract [en]

    According to Gestalt theory, any image is perceived subconsciously as a coherent structure (or whole) with two contrast substructures: figure and ground. The figure consists of numerous autogenerated substructures with an inherent hierarchy of far more smalls than larges. Through these substructures, the structural beauty of an image (L), or equivalently the livingness of space, can be computed by the multiplication of the number of substructures (S) and their inherent hierarchy (H). This definition implies that the more substructures something has, the more living or more structurally beautiful it is, and the higher the hierarchy of the substructures, the more living or more structurally beautiful. This is the nonrecursive approach to the structural beauty of images or the livingness of space. In this article we develop a recursive approach, which derives all substructures of an image (instead of its figure) and continues the deriving process for those decomposable substructures until none of them are decomposable. All of the substructures derived at different iterations (or recursive levels) together constitute a living structure; hence the notion of living images. We have applied the recursive approach to a set of images that have been previously studied in the literature and found that (1) the number of substructures of an image is far lower (3 percent on average) than the number of pixels and the centroids of the substructures can effectively capture the skeleton or saliency of the image; (2) all the images have a recursive level more than four, indicating that they are indeed living images; (3) no more than 3 percent of the substructures are decomposable, implying that a vast amount of the substructures are not decomposable; (4) structural beauty can be well measured by the recursively defined substructures, as well as their decomposable subsets. Despite a slightly higher computational cost, the recursive approach is proven to be more robust than the nonrecursive approach. The recursive approach and the nonrecursive approach both provide a powerful means to study the livingness or vitality of space in cities and communities.

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  • 23.
    Jiang, Bin
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Jia, Tao
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Agent-based simulation of human movement shaped by the underlying street structure2011In: International Journal of Geographical Information Science, ISSN 1365-8816, E-ISSN 1365-8824, Vol. 25, no 1, p. 51-64Article in journal (Refereed)
    Abstract [en]

    Relying on random and purposive moving agents, we simulated human movement in large street networks. We found that aggregate flow, assigned to individual streets, is mainly shaped by the underlying street structure, and that human moving behavior (either random or purposive) has little effect on the aggregate flow. This finding implies that given a street network, the movement patterns generated by purposive walkers (mostly human beings) and by random walkers are the same. Based on the simulation and correlation analysis, we further found that the closeness centrality is not a good indicator for human movement, in contrast to a long-standing view held by space syntax researchers. Instead we suggest that Google's PageRank and its modified version (weighted PageRank), betweenness and degree centralities are all better indicators for predicting aggregate flow.

  • 24.
    Jiang, Bin
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Liu, Xintao
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Automatic generation of the axial lines of urban environments to capture what we perceive2010In: International Journal of Geographical Information Science, ISSN 1365-8816, E-ISSN 1365-8824, Vol. 24, no 4, p. 545-558Article in journal (Refereed)
    Abstract [en]

    Based on the concepts of isovists and medial axes, we developed a set of algorithms that can automatically generate axial lines for representing individual linearly stretched parts of open space of an urban environment. Open space is the space between buildings where people can freely move around. The generation of the axial lines has been a key aspect of space syntax research, conventionally relying on hand-drawn axial lines of an urban environment, often called axial map, for urban morphological analysis. Although various attempts have been made towards an automatic solution, few of them can produce the axial map that consists of the least number of longest visibility lines, and none of them really works for different urban environments. Our algorithms provide a better solution than existing ones. Throughout this article, we have also argued and demonstrated that the axial lines constitute a true skeleton, superior to medial axes, in capturing what we perceive about the urban environment.

  • 25.
    Jiang, Bin
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Liu, Xintao
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Computing the fewest-turn map directions based on the connectivity of natural roads2011In: International Journal of Geographical Information Science, ISSN 1365-8816, E-ISSN 1365-8824, Vol. 25, no 7, p. 1069-1082Article in journal (Refereed)
    Abstract [en]

    In this article, we introduce a novel approach to computing the fewest-turn map directions or routes based on the concept of natural roads. Natural roads are joined road segments that perceptually constitute good continuity. This approach relies on the connectivity of natural roads rather than that of road segments for computing routes or map directions. Because of this, the derived routes possess the fewest turns. However, what we intend to achieve are the routes that not only possess the fewest turns but are also as short as possible. This kind of map direction is more effective and favored by people because they bear less cognitive burden. Furthermore, the computation of the routes is more efficient because it is based on the graph encoding the connectivity of roads, which is substantially smaller than the graph of road segments. We experimented on eight urban street networks from North America and Europe to illustrate the above-stated advantages. The experimental results indicate that the fewest-turn routes possess fewer turns and shorter distances than the simplest paths and the routes provided by Google Maps. For example, the fewest-turn-and-shortest routes are on average 15% shorter than the routes suggested by Google Maps, whereas the number of turns is just half as much. This approach is a key technology behind FromToMap.org – a web mapping service using openstreetmap data.

  • 26.
    Jiang, Bin
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Yao, Xiaobai
    University of Georgia, Athens, GA, USA.
    Geospatial analysis and modeling of urban structure and dynamics: an overview2010In: The GeoJournal Library, 2010, Volume 99, Part 1 / [ed] Bin Jiang and Xiaobai Yao, Berlin: Springer , 2010, p. 3-11Chapter in book (Other academic)
  • 27.
    Jägerbrand, Annika
    Statens väg- och transportforskningsinstitut.
    New Framework of Sustainable Indicators for Outdoor LED (Light Emitting Diodes) Lighting and SSL (Solid State Lighting)2015In: Sustainability, E-ISSN 2071-1050, Vol. 7, no 1, p. 1028-1063Article in journal (Refereed)
    Abstract [en]

    Light emitting diodes (LEDs) and SSL (solid state lighting) are relatively  new light sources, but are already widely applied for outdoor lighting. Despite this, there is little available information allowing planners and designers to evaluate and weigh different sustainability aspects of LED/SSL lighting when making decisions. Based on a literature review, this paper proposes a framework of sustainability indicators and/or measures that can be used for a general evaluation or to highlight certain objectives or aspects of special interest when choosing LED/SSL lighting. LED/SSL lighting is reviewed from a conventional sustainable development perspective, i.e., covering the three dimensions, including ecological, economic and social sustainability. The new framework of sustainable indicators allow prioritization when choosing LED/SSL products and can thereby help ensure that short-term decisions on LED/SSL lighting systems are in line with long-term sustainability goals established in society. The new framework can also be a beneficial tool for planners, decision-makers, developers and lighting designers, or for consumers wishing to use LED/SSL lighting in  a sustainable manner. Moreover, since some aspects of LED/SSL lighting have not yet been thoroughly studied or developed, some possible future indicators are suggested.

  • 28.
    Lim, Nancy Joy
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Land management, GIS.
    Modelling, mapping and visualisation of flood inundation uncertainties2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Flood maps showing extents of predicted flooding for a given extreme event have wide usage in all types of spatial planning tasks, as well as serving as information material for the public. However, the production processes that these maps undergo (including the different data, methods, models and decisions from the persons generating them), which include both Geographic Information Systems (GIS) and hydraulic modelling, affect the map’s content, and will be reflected in the final map. A crisp flood boundary, which is a common way of representing the boundary in flood maps, may therefore not be the best representation to be used. They provide a false implication that these maps are correct and that the flood extents are absolute, despite the effects of the entire modelling in the prediction output. Hence, this research attempts to determine how flood prediction outputs can be affected by uncertainties in the modelling process. In addition, it tries to evaluate how users understand, utilise and perceive flood uncertainty information. 

    Three main methods were employed in the entire research: uncertainty modelling and analyses; map and geovisualisation development; and user assessment. The studies in this work showed that flood extents produced were influenced by the Digital Elevation Model (DEM) resolution and the Manning’s  used. This effect was further increased by the topographic characteristic of the floodplain. However, the performance measure used, which quantify how well a model produces result in relation to a reference floor boundary, had also biases in quantifying outputs. Determining the optimal model output, therefore, depended on outcomes of the goodness-of-fit measures used.

     In this research, several ways were suggested on how uncertainties can be visualised based on the data derived from the uncertainty assessment and by characterising the uncertainty information. These can be through: dual-ended maps; flood probability maps; sequential maps either highlighting the degrees of certainty (certainty map) or degrees of uncertainty (uncertainty map) in the data; binary maps; overlain flood boundaries from different calibration results; and performance bars. Different mapping techniques and visual variables were used for their representation. These mapping techniques employed, as well as the design of graphical representation, helped facilitate understanding the information by the users, especially when tested during the evaluations. Note though that there were visualisations, which the user found easier to comprehend depending on the task given. Each of these visualisations had also its advantages and disadvantages in communicating flood uncertainty information, as shown in the assessments conducted. Another important aspect that came out in the study was how the users’ background influence decision-making when using these maps. Users’ willingness to take risks depended not only on the map, but their perceptions on the risk itself. However, overall, users found the uncertainty maps to be useful to be incorporated in planning tasks.

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  • 29.
    Lin, Yue
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    A Comparison Study on Head/tail Breaks and Topfer’s Method for Model-based Map Generalization on Geographic Features in Country and City Levels2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Map generalization is a traditional cartographical issue which should be particularly considered in today’sinformation age. The aim of this study is to find some characteristics about head/tail breaks which worksas generalization method compared with the well known Topfer’s method. A questionnaire survey wasconducted to let 30 users choose either of the series maps of both methods and the reason(s) for thatchoice. Also to test their understanding of the series maps histograms were added for them to match.Afterwards the sample results were analyzed using both univariate and bivariate analysis approaches. Itshows that the head/tail breaks method was selected by 58%, compared with 38.7% of Topfer’s method,because of its simplicity. By checking the correctness of histogram question it also shows that those whowell understood answers choose the head/tail breaks rather than the Topfer’s method. However in somecases, where the amount of geographical features is relatively small, Topfer’s method is more selectedbecause of its informative characteristic and similar structure to the original map. It was also found that inthe comparison the head/tail breaks is more advantageous in line feature type generalization than in arealfeature type. This is probably because Topfer’s method changes its minority selection rule to half selectionin line feature type, whereas the head/tail breaks keeps the scaling property. Any difference between thetwo tested scales, Finland level and Helsinki level, is not found in this comparison study. However, futurework should explore more regarding this and other issues.

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  • 30.
    Lozano, Rodrigo
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production.
    Bridging aims and delivery of higher education for sustainable development: Using pedagogical approaches to fulfil competences2019Conference paper (Refereed)
  • 31.
    Lozano, Rodrigo
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production.
    Drivers for and barriers to Corporate Sustainability2019Conference paper (Other academic)
  • 32.
    Lozano, Rodrigo
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production.
    Impulsores de la sostenibilidad corporativa [Corporate sustainability drivers]2019Conference paper (Other academic)
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  • 33.
    Lozano, Rodrigo
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production. Organisational Sustainability, Ltd, Cardiff, UK.
    Sustainable business models: providing a more holistic perspective2018In: Business Strategy and the Environment, ISSN 0964-4733, E-ISSN 1099-0836, Vol. 27, no 8, p. 1159-1166Article in journal (Refereed)
    Abstract [en]

    Corporate sustainability has recently been challenging traditional business models that have been based on value proposition, creation and capture. There has been a steady increase in publications using the term “sustainable business models”; however, there have been few that have theoretically defined or characterized the term, and in most cases, they just apply the term. Seven peer‐reviewed papers were selected that aimed to define and explain sustainable business models and that have been widely cited. The papers were analyzed by assessing the elements and activities covered using the corporate sustainability framework, and by comparing them against four approaches to explain organizations. The paper proposes a definition and framework for more sustainable business models aimed at integrating organizational approaches, the company system, stakeholders, change and sustainability dimensions, thus providing a more holistic and systemic approach to discourses on sustainable business models.

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  • 34.
    Lozano, Rodrigo
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production. Organisational Sustainability, Cardiff, UK.
    Barreiro-Gen, Maria
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production.
    Analysing the incorporation of sustainable development into European Higher Education Institution's curricula2019In: Engineering Education towards Sustainability: Approaches for Institutionalization and Teaching Implementation: Second Internacional Conference on Engineering Education for the 21st Century – ICEE21C 2019 / [ed] Guraya, T., Cabedo, L., Bilbao: Universidad del País Vasco / Euskal Herriko Unibertsitatea , 2019, p. 51-56Conference paper (Other academic)
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  • 35.
    Lozano, Rodrigo
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production.
    Carpenter, Angela
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production.
    Sammalisto, Kaisu
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Management, Industrial Design and Mechanical Engineering, Industrial Management. University of Gävle, Center for Logistics and Innovative Production.
    Analysing organisational change management in seaports: Stakeholder perception, communication, drivers for, and barriers to sustainability at the Port of Gävle2020In: European port cities in transition: Moving towards more sustainable sea transport hubs, Springer, 2020Chapter in book (Other academic)
  • 36.
    Lozano, Rodrigo
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Industrial economics. University of Gävle, Center for Logistics and Innovative Production.
    Findler, Florian
    Schönherr, Norma
    Stacherl, Barbara
    Making the Invisible Visible: Impact Assessment in Higher Education2018In: Proceedings of the International Association for Business and Society: Proceedings of the Twenty-Ninth Annual Meeting, 2018Conference paper (Refereed)
  • 37.
    Maekawa, Ikumi
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science.
    Pålsson, Kajsa
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science.
    Nature experiences for human wellbeing and Human-Nature Connection2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Our contact with nature is decreasing in what has been referred to as the “extinction of experience”. Consequences of the loss of nature experiences are far-reaching and involve not only changes in health and wellbeing, but also changes emotions, attitudes, and behaviour towards nature. This research aims to fill a knowledge gap in understanding specific characteristics of nature experiences in relation to both a) generating human wellbeing, and b) improving Human-Nature Connection (HNC), defined as how people relate to nature. The aim is to increase our understanding of the characteristics of nature experiences that can achieve both of these positive outcomes. Furthermore, this research explores an organisational perspective through interviewing organisations that are currently incorporating or thinking to implement practices that include nature experiences. To address the main aim, an integrative literature review was conducted, and the results revealed that intentional contact, active engagement (specifically appreciative outdoor activities, cognitive engagement, cues, and direct earth contact), and biodiversity and wildness to be significant characteristics that positively impact human beings. Moreover, appreciative outdoor activities and cognitive engagement have been shown to be beneficial even when passive. In addition, there is some evidence that there is a link between HNC and wellbeing, which suggests that improving HNC would increase the wellbeing effects experienced by an individual during a nature experience. This knowledge is crucial for designing nature experiences that are able to more efficiently improve wellbeing, as well as improve HNC. Regarding the organisational perspective, a barrier that needs to be overcome is reaching an understanding of the benefits of such experiences, not only for the employees but for the business. One major opportunity identified is the hybrid working model, which allows employees to work remotely, and the possibility for the company to actively encourage its employees to experience nature.

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    Nature experiences for human wellbeing and Human-Nature Connection
  • 38.
    Melander, Sandra
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building Engineering, Energy Systems and Sustainability Science, Environmental Science.
    Somebody should do something: A qualitative study to determine challenges that politicians face in decsion-making to mitigate climate change2022Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Climate change is known to cause more frequently occurring extreme events which threaten both natural and human systems as we know them. Island nations are particularly vulnerable to these climate-induced changes, and the Åland Islands are no exception to this rule. Åland has already seen a change in typical climate patterns as the temperature has been increasing and precipitation decreasing, which is a cause for concern. Political leaders have a great responsibility to mitigate climate change, through decisions on policy implementation and other legislative action, to strive towards sustainability. However, change is not being made fast enough. Hence, this study aims to determine the challenges that politicians of the Parliament of Åland face when making decisions that promote climate change mitigation, as well as seek why these challenges are present. The study was conducted through qualitative interviews with the seven political group leaders, one for each represented party, that participate in Bärkraft’s group leader forum. Bärkraft is a local network on Åland which strive toward sustainability through its Development and Sustainability Agenda. In addition, the main secretary of Bärkraft was interviewed. The interviews demonstrated that a majority of the participants had previous experience with climate change issues although, just under half of the respondents agreed that Åland faces little to no climate-related risks. From the interviews six themes were identified which relate to challenges in decision-making for climate change mitigation. For instance, a clear majority of the participants mentioned different economic aspects as a barrier in decision-making, likewise, the abstractness of climate change mitigation was deemed as challenging to handle, and marketing climate change mitigation to the citizens and other politicians was seen as challenging since proper arguments are essential for success. In addition, twelve sub-challenges were found that explains why the identified challenges are present. These sub-challenges included e.g., electoral popularity, municipal planning, motivation, etc. In conclusion, these challenges, with associated sub-challenges, highlight the complexity and uncertainty of climate change mitigation which sets barriers for the political leaders in making decisions for policy implementation. The study would have benefited from a larger number of participants. It also has limited generalizability, being a specific case and not including the complete decision-making process for policy implementation and viewpoints from other societal actors. However, the mentioned limitations can be subject to further research on the topic.

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    Somebody should do something
  • 39.
    Märdla, Silja
    et al.
    Tallinn University of Technology, Estonia.
    Ellmann, Artu
    Tallinn University of Technology, Estonia.
    Ågren, Jonas
    Lantmäteriet.
    Sjöberg, Lars
    KTH.
    Regional geoid computation by least squares modified Hotine’s formula with additive corrections2018In: Journal of Geodesy, ISSN 0949-7714, E-ISSN 1432-1394, Vol. 92, no 3, p. 253-270Article in journal (Refereed)
    Abstract [en]

    Geoid and quasigeoid modelling from gravity anomalies by the method of least squares modification of Stokes’s formula with additive corrections is adapted for the usage with gravity disturbances and Hotine’s formula. The biased, unbiased and optimum versions of least squares modification are considered. Equations are presented for the four additive corrections that account for the combined (direct plus indirect) effect of downward continuation (DWC), topographic, atmospheric and ellipsoidal corrections in geoid or quasigeoid modelling. The geoid or quasigeoid modelling scheme by the least squares modified Hotine formula is numerically verified, analysed and compared to the Stokes counterpart in a heterogeneous study area. The resulting geoid models and the additive corrections computed both for use with Stokes’s or Hotine’s formula differ most in high topography areas. Over the study area (reaching almost 2 km in altitude), the approximate geoid models (before the additive corrections) differ by 7 mm on average with a 3 mm standard deviation (SD) and a maximum of 1.3 cm. The additive corrections, out of which only the DWC correction has a numerically significant difference, improve the agreement between respective geoid or quasigeoid models to an average difference of 5 mm with a 1 mm SD and a maximum of 8 mm.

  • 40.
    Märdla, Silja
    et al.
    Tallinn University of Technology, Estonia.
    Ågren, Jonas
    Lantmäteriet.
    Strykowsky, Gabriel
    Technical University of Denmark.
    Oja, Tönis
    Estonian Land Board.
    Ellmann, Artu
    Tallinn University of Technology, Estonia.
    Forsberg, René
    Technical University of Denmark.
    Bilker-Koivula, Mirjam
    Land Survey of Finland.
    Omang, Ove
    Norwegian Mapping Authority.
    Parseliunas, Eimuntas
    Vilinius Gediminas Technical Univesity, Lithuania.
    Liepins, Ivars
    Latvian Geospatial Information Agency.
    From discrete gravity survey data to a high-resolution gravity field representation in the Nordic-Baltic region2017In: Marine Geodesy, ISSN 0149-0419, E-ISSN 1521-060X, Vol. 40, no 6, p. 416-453Article in journal (Refereed)
    Abstract [en]

    The deduction of a regularly spaced gravity anomaly grid from scattered survey data is studied, addressing mainly two aspects: reduction of gravity to anomalies and subsequent interpolation by various methods. The problem is illustrated in a heterogeneous study area and contrasting test areas including mountains, low terrains, and a marine area. Provided with realistic error estimates, Least Squares Collocation interpolation of Residual Terrain Model anomalies yields the highest quality gravity grid. In most cases, the Bouguer reduction and other interpolation methods tested are equally viable. However, spline-based interpolation should be avoided in marine areas with trackwise survey data.

  • 41.
    Novák, Pavel
    et al.
    University of West Bohemia, Plzeň, Czech Republic.
    Tenzer, Robert
    National School of Surveying, Division of Sciences, University of Otago, Dunedin, New Zealand.
    Eshagh, Mehdi
    Royal Institute of Technology, Stockholm, Sweden.
    Bagherbandi, Mohammad
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Evaluation of gravitational gradients generated by Earth's crustal structures2013In: Computers & Geosciences, ISSN 0098-3004, E-ISSN 1873-7803, Vol. 51, p. 22-33Article in journal (Refereed)
    Abstract [en]

    Spectral formulas for the evaluation of gravitational gradients generated by upper Earth’s mass components are presented in the manuscript. The spectral approach allows for numerical evaluation of global gravitational gradient fields that can be used to constrain gravitational gradients either synthesised from global gravitational models or directly measured by the spaceborne gradiometer on board of the GOCE satellite mission. Gravitational gradients generated by static atmospheric, topographic and continental ice masses are evaluated numerically based on available global models of Earth’s topography, bathymetry and continental ice sheets. CRUST2.0 data are then applied for the numerical evaluation of gravitational gradients generated by mass density contrasts within soft and hard sediments, upper, middle and lower crust layers. Combined gravitational gradients are compared to disturbing gravitational gradients derived from a global gravitational model and an idealised Earth’s model represented by the geocentric homogeneous biaxial ellipsoid GRS80. The methodology could be used for improved modelling of the Earth’s inner structure.

  • 42.
    Paasch, Jesper M.
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences. Aalborg University, Copenhagen, Denmark.
    Paulsson, Jenny
    KTH Royal Institute of Technology.
    Trends in 3D cadastre – A literature survey2023In: Land use policy, ISSN 0264-8377, E-ISSN 1873-5754, Vol. 131, article id 106716Article, review/survey (Refereed)
    Abstract [en]

    The formation and alteration of real property and rights, restrictions and responsibilities are important parts of land administration. Research on the distribution of publications in the three-dimensional (3D) cadastral domain has been in focus as a specialised part of real property research during the last decades. A number of literature surveys on research trends in the domain show a growing number of publications during the last decades. The number of publications have increased considerably within a range of topics, classified into legal, technical, registration and organisational categories of 3D property. The purpose of the research presented here is to contribute to these analyses of the number and thematic distribution of the 3D cadastral domain literature by analysing three aspects: 1) To add to the recent study by including 3D cadastre publications published during 2021 (Paasch and Paulsson, 2021b, Paasch and Paulsson, 2021a); 2) To briefly analyse the classification of 3D cadastre research in technical programmes and proceedings of major conferences focussing, in total or in part, on 3D cadastre. 3) The results are used to contribute to the discussion regarding if the 3D cadastral domain is too diverse today to talk about a single 3D cadastral domain. An input to the discussion of what constitutes a domain is provided from an analysis of another land administration research topic that is often addressed in relation to 3D real property research; the international standard for land administration, the Land Administration Domain Model, LADM, ISO 19152.

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  • 43.
    Sahlin, Eva A.U.
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    Glasser, Neil F.
    Institute of Geography and Earth Sciences, Aberystwyth University, Wales.
    The Geomorphological Map of Wales and its use in Geoconservation Assessment (poster)2011Conference paper (Other academic)
    Abstract [en]

    A geomorphological map is probably the most comprehensive way of illustrating the landform distribution, surface form, material, age, and the processes responsible for the landscape look. As such geomorphological maps are invaluable in the fields of geoconservation assessment, evaluation and management. It is therefore an oddity, as well as an inconvenience, that there is no systematic landform inventory or mapping of the geomorphology that is comparable to the surveys undertaken for geology or soils in the UK. For that purpose the project of “Developing a Geomorphological Map of Wales” was initiated by the Countryside Council for Wales (CCW) as part of a PhD project investigating the Quaternary glaciations of Wales.

    To develop a mapping methodology suitable for the Welsh landscape, three contrasting areas were selected to provide a wide range of geomorphological features. Aerial photography, satellite imagery, digital elevation models, and field investigations of landform/sediment associations, formed the foundation for landform interpretation, which were compiled in a GIS.

    Geomorphological maps of Cadair Idris, and the Central and North Cambrian Mountains were produced, scale 1:10 000 – 1:25 000. The maps form an extensive inventory of the geomorphological geodiversity, and were used for providing data to palaeoglaciological reconstructions and making geoconservation recommendations to the CCW. The recommended sites are of regional interest; their rareness, distinct morphology, interesting research and educational value makes them worthy of RIGS (Regional Important Geodiversity Sites) protection.

    A Geomorphological Map of Wales has the potential for wider practical, scientific and educational benefits, such as for governmental bodies, local authority planners, tourism, researchers, teachers, landowners and land managers. Without a full account of all the geomorphological components of a landscape, there can be no full understanding of the landscape history or the various landforming processes. Important geodiversity sites may be overlooked, badly managed or lost before their full potential are realised.

  • 44.
    Schwabe, Joachim
    et al.
    Federal Agency for Cartography and Geodesy (Germany).
    Ågren, Jonas
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    Liebsch, Gunter
    Federal Agency for Cartography and Geodesy (Germany).
    Westfeld, Patric
    Federal Maritime and Hydrographic Agency (Germany).
    Hammarklint, Thomas
    Swedish Maritime Administration (Sweden).
    Mononen, Jyrki
    Finnish Transport Agency (Finland).
    Andersen, Ole B
    DTU Space (Denmark).
    The Baltic Sea Chart Datum 2000 (BSCD2000): Implementation of a common reference level in the Baltic Sea2020In: The international hydrographic review, ISSN 0020-6946, no 23, p. 63-83Article in journal (Other academic)
    Abstract [en]

    The Baltic Sea Chart Datum 2000 (BSCD2000) is a geodetic reference system adopted for Baltic Sea hydrographic surveying, hydrographic engineering, nautical charts, navigational publications and water level information. It is based on the common geodetic standards for the height system (EVRS) and the spatial reference system (ETRS89) in Europe. In particular, the zero level of BSCD2000 is in accordance with the Normaal Amsterdams Peil (NAP). BSCD2000 is about to be adopted as unified chart datum by all the countries around the Baltic Sea. It agrees with most national height realizations used on land. BSCD2000 will facilitate effective use of GNSS methods like GPS, GLONASS and Galileo for accurate navigation and hydrographic surveying in the future.

  • 45.
    Seipel, Stefan
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Computer Science. Uppsala university.
    Andrée, Martin
    Lantmäteriet.
    Larsson, Karolina
    Lantmäterimyndigheten.
    Paasch, Jesper M.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences. Lantmäteriet; Aalborg university.
    Paulsson, Jenny
    KTH.
    Visualisation of 3D Property Data and Assessment of the Impact of Rendering Attributes2020In: Journal of Geovisualization and Spatial Analysis, ISSN 2509-8810, E-ISSN 2509-8829, Vol. 4, no 2, article id 23Article in journal (Refereed)
    Abstract [en]

    Visualisations of 3D cadastral information incorporating both intrinsically spatial andnon-spatial information are examined here. The design of a visualisation prototype islinked to real case 3D property information. In an interview with domain experts, thefunctional and visual features of the prototype are assessed. The choice of renderingattributes was identified as an important aspect for further analysis. A computationalapproach to systematic assessment of the consequences of different graphical designchoices is proposed. This approach incorporates a colour similarity metric, visualsaliency maps, and k-nearest neighbour (kNN) classification to estimate risks ofconfusing or overlooking relevant elements in a visualisation.The results indicate that transparency is not an independent visual variable, as itaffects the apparent colour of 3D objects and makes them inherently more difficult todistinguish. Transparency also influences visual saliency of objects in a scene. Theproposed analytic approach was useful for visualisation design and revealed that theconscious use of graphical attributes, like combinations of colour, transparency andline styles, can improve saliency of objects in a 3D scene.

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  • 46.
    Sjöberg, Lars
    et al.
    Division of Geodesy and Satellite Positioning KTH.
    Abrehdary, Majid
    Division of Geodesy and Satellite Positioning.
    Bagherbandi, Mohammad
    Division of Geodesy and Satellite Positioning KTH.
    The observed geoid height versus Airy's and Pratt's isostatic models using matched asymptotic expansions2014In: Acta Geodaetica et Geophysica Hungarica, ISSN 1217-8977, E-ISSN 1587-1037, Vol. 49, no 4, p. 473-490Article in journal (Refereed)
    Abstract [en]

    Isostasy is a key concept in geodesy and geophysics. The classical isostatic models of Airy/Heiskanen and Pratt/Hayford imply that the topographic mass surplus and ocean mass deficit are balanced by mountain roots and anti-roots in the former model and by density variations in the topography and the compensation layer below sea bottom in the latter model. In geophysics gravity inversion is an essential topic where isostasy comes to play. The main objective of this study is to compare the prediction of geoid heights from the above isostatic models based on matched asymptotic expansion with geoid heights observed by the Earth Gravitational Model 2008. Numerical computations were carried out both globally and in several regions, showing poor agreements between the theoretical and observed geoid heights. As an alternative, multiple regression analysis including several non-isostatic terms in addition to the isostatic terms was tested providing only slightly better success rates. Our main conclusion is that the geoid height cannot generally be represented by the simple formulas based on matched asymptotic expansions. This is because (a) both the geoid and isostatic compensation of the topography have regional to global contributions in addition to the pure local signal considered in the classical isostatic models, and (b) geodynamic phenomena are still likely to significantly blur the results despite that all spherical harmonic low-degree (below degree 11) gravity signals were excluded from the study.

  • 47.
    Sjöberg, Lars
    et al.
    Royal Institute of Technology (KTH), Stockholm, Sweden .
    Bagherbandi, Mohammad
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Urban and regional planning/GIS-institute.
    A study on the Fennoscandian post-glacial rebound as observed by present-day uplift rates and gravity field model GOCO02S2013In: Acta Geodaetica et Geophysica Hungarica, ISSN 1217-8977, E-ISSN 1587-1037, Vol. 48, no 3, p. 317-331Article in journal (Refereed)
    Abstract [en]

    Repeated absolute gravity measurements in Fennoscandia have revealed that the on-going post-glacial rebound can be regarded as a pure viscous flow of mantle mass of density 3390 kg/m3 towards the central part of the region caused by a gravity/uplift rate of −0.167 μGal/mm. Our model estimates the rebound induced rates of changes of surface gravity and geoid height to have peaks of −1.9 μGal/yr and 1.6 mm/yr, respectively, the former being consistent with absolute gravity observations. The correlation coefficient of the spherical harmonic representations of the geoid height and uplift rate for the spectral windows between degrees 10 and 70 is estimated to −0.99±0.006, and the maximum remaining land uplift is estimated to the order of 80 m. Both the (almost) linear increase of relaxation time with degree and the linear relation between geoid height and uplift rate support a model with mass flow in the major part of the mantle and disqualify the model with a flow in a thin channel below the crust. The mean viscosity of the flow in the central uplift region is estimated to 4×1021 Pa s.

  • 48.
    Sjöberg, Lars E.
    et al.
    Royal Institute of Technology, Stockholm, Sweden.
    Bagherbandi, Mohammad
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Land management, GIS. Royal Institute of Technology, Stockholm, Sweden.
    Isostasy - Geodesy2016In: Encyclopedia of Geodesy / [ed] Grafarend, Erik, Springer , 2016Chapter in book (Other academic)
    Abstract [en]

    Isostasy (Greek isos “equal,” stasis “stand still”) is a term in geology, geophysics, and geodesy to describe the state of mass balance (equilibrium) between the Earth’s crust and upper mantle. It describes a condition to which the mantle tends to balance the mass of the crust in the absence of external forces.

  • 49.
    Sánchez, Laura
    et al.
    Technical University of Munich.
    Ågren, Jonas
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences. Lantmäteriet; KTH.
    Huang, Jianliang
    Natural Resources Canada.
    Wang, Yan Ming
    National Geodetic Survey, USA.
    Mäkinen, Jaakko
    Finnish Geospatial Research Institute.
    Pail, Roland
    Technical University of Munich.
    Barzaghi, Riccardo
    Politecnico Di Milano.
    Vergos, Georgios S.
    Aristotle University of Thessaloniki.
    Ahlgren, Kevin
    National Geodetic Survey, USA.
    Liu, Qing
    Technical University of Munich.
    Strategy for the realisation of the International Height Reference System (IHRS)2021In: Journal of Geodesy, ISSN 0949-7714, E-ISSN 1432-1394, Vol. 95, article id 33Article in journal (Refereed)
    Abstract [en]

    In 2015, the International Association of Geodesy defned the International Height Reference System (IHRS) as the conventional gravity feld-related global height system. The IHRS is a geopotential reference system co-rotating with the Earth.Coordinates of points or objects close to or on the Earth’s surface are given by geopotential numbers C(P) referring to anequipotential surface defned by the conventional value W0=62,636,853.4 m2 s−2, and geocentric Cartesian coordinates Xreferring to the International Terrestrial Reference System (ITRS). Current eforts concentrate on an accurate, consistent,and well-defned realisation of the IHRS to provide an international standard for the precise determination of physical coordinates worldwide. Accordingly, this study focuses on the strategy for the realisation of the IHRS; i.e. the establishment ofthe International Height Reference Frame (IHRF). Four main aspects are considered: (1) methods for the determination ofIHRF physical coordinates; (2) standards and conventions needed to ensure consistency between the defnition and the realisation of the reference system; (3) criteria for the IHRF reference network design and station selection; and (4) operationalinfrastructure to guarantee a reliable and long-term sustainability of the IHRF. A highlight of this work is the evaluation ofdiferent approaches for the determination and accuracy assessment of IHRF coordinates based on the existing resources,namely (1) global gravity models of high resolution, (2) precise regional gravity feld modelling, and (3) vertical datumunifcation of the local height systems into the IHRF. After a detailed discussion of the advantages, current limitations, andpossibilities of improvement in the coordinate determination using these options, we defne a strategy for the establishmentof the IHRF including data requirements, a set of minimum standards/conventions for the determination of potential coordinates, a frst IHRF reference network confguration, and a proposal to create a component of the International Gravity FieldService (IGFS) dedicated to the maintenance and servicing of the IHRS/IHRF

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  • 50.
    Tenzer, Robert
    et al.
    The Key Laboratory of Geospace Environment and GeodesySchool of Geodesy and Geomatics, Wuhan UniversityWuhanChina.
    Bagherbandi, Mohammad
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences. Division of Geodesy and Satellite Positioning.
    Comparative Study of the Uniform and Variable Moho Density Contrast in the Vening Meinesz-Moritz’s Isostatic Scheme for the Gravimetric Moho Recovery2014In: IGFS 2014, Proceedings of the 3rd International Gravity Field Service (IGFS), Shanghai, China, 30 June - 6 July 2014 / [ed] Shuanggen Jin, Riccardo Barzaghi, Springer, 2014, p. 199-207Conference paper (Refereed)
    Abstract [en]

    In gravimetric methods for a determination of the Moho geometry, the constant value of the Moho density contract is often adopted. Results of gravimetric and seismic studies, however, showed that the Moho density contrast varies significantly. The assumption of a uniform density contrast thus might yield large errors in the estimated Moho depths. In this study we investigate these errors by comparing the Moho depths determined globally for the uniform and variable models of the Moho density contrast. These two gravimetric results are obtained based on solving the Vening Meinesz-Moritz’s inverse problem of isostasy. The uniform model of the Moho density contrast is defined individually for the continental and oceanic lithosphere to better reproduce the reality. The global data of the lower crust and upper mantle retrieved from the CRUST1.0 seismic crustal model are used to define the variable Moho density contrast. This seismic model is also used to validate both gravimetric solutions. Results of our numerical experiment reveals that the consideration of the variable Moho density contrast improves the agreement between the gravimetric and seismic Moho models; the RMS of differences is 5.4 km (for the uniform density contrast) and 4.7 km (for the variable density contrast).

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