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  • 1.
    Alizadeh Khameneh, Mohammad Amin
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Tree Detection and Species Identification using LiDAR Data2013Självständigt arbete på avancerad nivå (masterexamen), 30 poäng / 45 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The importance of single-tree-based information for forest management and related industries in countries like Sweden, which is covered in approximately 65% by forest, is the motivation for developing algorithms for tree detection and species identification in this study. Most of the previous studies in this field are carried out based on aerial and spectral images and less attention has been paid on detecting trees and identifying their species using laser points and clustering methods.

    In the first part of this study, two main approaches of clustering (hierarchical and K-means) are compared qualitatively in detecting 3-D ALS points that pertain to individual tree clusters. Further tests are performed on test sites using the supervised k-means algorithm in which the initial clustering points are defined as seed points. These points, which represent the top point of each tree are detected from the cross section analysis of the test area. Comparing those three methods (hierarchical, ordinary K-means and supervised K-means), the supervised K-means approach shows the best result for clustering single tree points. An average accuracy of 90% is achieved in detecting trees. Comparing the result of the thesis algorithms with results from the DPM software, developed by the Visimind Company for analysing LiDAR data, shows more than 85% match in detecting trees.

    Identification of trees is the second issue of this thesis work. For this analysis, 118 trees are extracted as reference trees with three species of spruce, pine and birch, which are the dominating species in Swedish forests. Totally six methods, including best fitted 3-D shapes (cone, sphere and cylinder) based on least squares method, point density, hull ratio and slope changes of tree outer surface are developed for identifying those species. The methods are applied on all extracted reference trees individually. For aggregating the results of all those methods, a fuzzy logic system is used because of its good reputation in combining fuzzy sets with no distinct boundaries. The best-obtained model from the fuzzy system provides 73%, 87% and 71% accuracies in identifying the birch, spruce and pine trees, respectively. The overall obtained accuracy in species categorization of trees is 77%, and this percentage is increased dealing with only coniferous and deciduous types classification. Classifying spruce and pine as coniferous versus birch as deciduous species, yielded to 84% accuracy.

  • 2.
    Amin, Hadi
    et al.
    Faculty of Engineering and Sustainable Development, The University of Gävle.
    Sjöberg, Lars
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Fastigheter och byggande, Geodesi och satellitpositionering. Faculty of Engineering and Sustainable Development, University of Gävle.
    Bagherbandi, Mohammad
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Fastigheter och byggande, Geodesi och satellitpositionering. Faculty of Engineering and Sustainable Development, The University of Gävle.
    A global vertical datum defined by the conventional geoid potential and the Earth ellipsoid parameters2019Ingår i: Journal of Geodesy, ISSN 0949-7714, E-ISSN 1432-1394Artikel i tidskrift (Refereegranskat)
    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.

  • 3.
    Bagherbandi, Mohammad
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Sjöberg, Lars E.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik. University of Gävle, Sweden .
    Improving gravimetric-isostatic models of crustal depth by correcting for non-isostatic effects and using CRUST2.02013Ingår i: Earth-Science Reviews, ISSN 0012-8252, E-ISSN 1872-6828, Vol. 117, s. 29-39Artikel i tidskrift (Refereegranskat)
    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.

  • 4.
    Bagherbandi, Mohammad
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Tenzer, R.
    Geoid-to-quasigeoid separation computed using the GRACE/GOCE global geopotential model GOCO02S -A case study of Himalayas and Tibet2013Ingår i: Terrestrial, Atmospheric and Oceanic Science, ISSN 1017-0839, E-ISSN 2223-8964, Vol. 24, nr 1, s. 59-68Artikel i tidskrift (Refereegranskat)
    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.

  • 5.
    Balazadegan Sarvrood, Yashar
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik och Geodesi.
    Amin, Md Nurul
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik och Geodesi.
    Server Based Real Time GPS-IMU Integration Aided by Fuzzy Logic Based Map Matching Algorithm for Car Navigation2011Självständigt arbete på avancerad nivå (masterexamen), 30 poäng / 45 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The stand-alone Global Positioning System (GPS) or an Integrated GPS and Dead Reckoning Systems (such as Inertial Navigation System or Odometer and magnetometer) have been widely used for vehicle navigation. An essential process in such an application is to map match the position obtained from GPS (or/and other sensors) on a digital road network map.

    GPS positioning is relatively accurate in open sky conditions, but its position is not accurate in dense urban canyon conditions where GPS is affected by signal blockage and multipath. High sensitivity GPS (HS GPS) receivers, can increase the availability, but are affected by multipath and cross correlation due to weak signal tracking. Inertial navigation system can be used to bridge GPS gaps, However, position and velocity results in such conditions are typically biased, therefore, fuzzy logic  based map matching, is mostly used because it can take noisy, imprecise input, to yield crisp (i.e. numerically accurate) output. Fuzzy logic can be applied effectively to map match the output from a High sensitivity GPS receiver or integrated GPS and INS in urban canyons because of its inherent tolerance to imprecise inputs.

    In this thesis stand-alone GPS positioning and integrated GPS and Inertial Measurement Unit (IMU) positioning aided by fuzzy logic based map matching for Stockholm urban and suburban areas are performed.  A comparison is carried out between, Map matching for stand-alone GPS and integrated GPS and IMU. Stand-alone GPS aided map matching algorithms identifies 96.4% of correct links for rural area, 92.6% for urban area (car test) and 93.4% for bus test in urban area. Integrated GPS and IMU aided map matching algorithms identifies 97.3% of correct links for rural area, 94.4% for urban area (car test) and 94.4% for bus test in urban area. Integrated GPS and Inertial Measurement Unit produces better vehicle azimuth than stand-alone GPS, especially at low speed. Furthermore, there are five more fuzzy rules based on gyro rate in integrated GPS and IMU map matching algorithm. Therefore, it shows better map matching results. GPS blackout happens rarely in Stockholm, because there are not many tall buildings in this city. Therefore, the integrated GPS and IMU aided by map matching shows only small improvement over stand-alone GPS aided by map matching.

  • 6. Bhowmick, S.
    et al.
    Nath, B.
    Halder, Dipti
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Biswas, Ashis
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Majumder, S.
    Mondal, P.
    Chakraborty, S.
    Nriagu, J.
    Bhattacharya, Prosun
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Iglesias, M.
    Roman-Ross, G.
    Guha Mazumder, D.
    Bundschuh, J.
    Chatterjee, D.
    Arsenic mobilization in the aquifers of three physiographic settings of West Bengal, India: Understanding geogenic and anthropogenic influences2013Ingår i: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 262, s. 915-923Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A comparative hydrogeochemical study was carried out in West Bengal, India covering three physiographic regions, Debagram and Chakdaha located in the Bhagirathi-Hooghly alluvial plain and Baruipur in the delta front, to demonstrate the control of geogenic and anthropogenic influences on groundwater arsenic (As) mobilization. Groundwater samples (n=90) from tube wells were analyzed for different physico-chemical parameters. The low redox potential (Eh=-185 to -86mV) and dominant As(III) and Fe(II) concentrations are indicative of anoxic nature of the aquifer. The shallow (<100m) and deeper (>100m) aquifers of Bhagirathi-Hooghly alluvial plains as well as shallow aquifers of delta front are characterized by Ca2+HCO3 - type water, whereas Na+ and Cl- enrichment is found in the deeper aquifer of delta front. The equilibrium of groundwater with respect to carbonate minerals and their precipitation/dissolution seems to be controlling the overall groundwater chemistry. The low SO4 2- and high DOC, PO4 3- and HCO3 - concentrations in groundwater signify ongoing microbial mediated redox processes favoring As mobilization in the aquifer. The As release is influenced by both geogenic (i.e. geomorphology) and anthropogenic (i.e. unsewered sanitation) processes. Multiple geochemical processes, e.g., Fe-oxyhydroxides reduction and carbonate dissolution, are responsible for high As occurrence in groundwaters.

  • 7. Blomqvist, Göran
    et al.
    Riehm, Mats
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik, Biogeofysik.
    Jansson, Per-Erik
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik, Biogeofysik.
    ROAD SURFACE WETNESS AS AFFECTED BY EVAPORATION, SURFACE RUNOFF AND TRAFFIC SPLASHINGManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Road surface wetness governs the fate of pollutants on the road surface. The wetness is also important for estimating the risk of ice formation during winters. The road surface water is affected by evaporation, run-off and traffic induced splash and spray. Increased knowledge of how these processes govern the road surface water and how they could be modelled would help to improve the possibility to abate problems with raised levels of air pollutants, as well as traffic safety issues by facilitating optimization of the use of anti- and de-icing chemicals. The aim of this study was to use a modeling tool in order to differentiate between three processes governing the loss of wetness from the road surface within a cross section of a road during two different climatic scenes (winter and spring). Two new measurement techniques were used for detailed measurements of road surface wetness across a road to validate the model. It could be concluded that the changes in wetness on the road can be simulated from general simple weather and traffic information. Furthermore, the wetness across the road is very heterogeneous and can be described by a distribution of regulating parameter values. The presented model application has a potential for real time application on roads and within a region and also for predictions of future conditions by using weather forecast data.

  • 8.
    Bradley, Karin
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Urbana och regionala studier.
    Hedrén, Johan
    Green utopianism: Perspectives, politics and micro-practices2014Samlingsverk (redaktörskap) (Övrigt vetenskapligt)
    Abstract [en]

    Utopian thought and experimental approaches to societal organization have been rare in the last decades of planning and politics. Instead, there is a widespread belief in ecological modernization, that sustainable societies can be created within the frame of the current global capitalist world order by taking small steps such as eco-labeling, urban densification, and recycling. However, in the context of the current crisis in which resource depletion, climate change, uneven development, and economic instability are seen as interlinked, this belief is increasingly being questioned and alternative developmental paths sought. This collection demonstrates how utopian thought can be used in a contemporary context, as critique and in exploring desired futures. The book includes theoretical perspectives on changing global socio-environmental relationships and political struggles for alternative development paths, and analyzes micro-level practices in co-housing, alternative energy provision, use of green space, transportation, co-production of urban space, peer-to-peer production and consumption, and alternative economies. It contributes research perspectives on contemporary green utopian practices and strategies, combining theoretical and empirical analyses to spark discussions of possible futures.

  • 9.
    Breuillard, H.
    et al.
    Uppsala universitet, Institutet för rymdfysik, Uppsalaavdelningen.
    Yordanova, Emiliya
    Uppsala universitet, Institutet för rymdfysik, Uppsalaavdelningen.
    Vaivads, Andris
    Uppsala universitet, Institutet för rymdfysik, Uppsalaavdelningen.
    Alexandrova, O.
    LESIA Observ Paris Meudon, Meudon, France..
    The Effects Of Kinetic Instabilities On Small-Scale Turbulence In Earth's Magnetosheath2016Ingår i: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 829, nr 1, artikel-id 54Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Earth's magnetosheath is the region delimited by the bow shock and the magnetopause. It is characterized by highly turbulent fluctuations covering all scales from MHD down to kinetic scales. Turbulence is thought to play a fundamental role in key processes such as energy transport and dissipation in plasma. In addition to turbulence, different plasma instabilities are generated in the magnetosheath because of the large anisotropies in plasma temperature introduced by its boundaries. In this study we use high-quality magnetic field measurements from Cluster spacecraft to investigate the effects of such instabilities on the small-scale turbulence (from ion down to electron scales). We show that the steepening of the power spectrum of magnetic field fluctuations in the magnetosheath occurs at the largest characteristic ion scale. However, the spectrum can be modified by the presence of waves/structures at ion scales, shifting the onset of the small-scale turbulent cascade toward the smallest ion scale. This cascade is therefore highly dependent on the presence of kinetic instabilities, waves, and local plasma parameters. Here we show that in the absence of strong waves the small-scale turbulence is quasi-isotropic and has a spectral index alpha approximate to 2.8. When transverse or compressive waves are present, we observe an anisotropy in the magnetic field components and a decrease in the absolute value of alpha. Slab/2D turbulence also develops in the presence of transverse/compressive waves, resulting in gyrotropy/non-gyrotropy of small-scale fluctuations. The presence of both types of waves reduces the anisotropy in the amplitude of fluctuations in the small-scale range.

  • 10.
    Bundschuh, Jochen
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Maity, J. P.
    Nath, B.
    Baba, A.
    Gunduz, O.
    Kulp, T. R.
    Jean, J. -S
    Kar, S.
    Yang, H. -J
    Tseng, Y. -J
    Bhattacharya, Prosun
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Chen, C. -Y
    Naturally occurring arsenic in terrestrial geothermal systems of western Anatolia, Turkey: Potential role in contamination of freshwater resources2013Ingår i: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 262, s. 951-959Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Arsenic (As) contamination in terrestrial geothermal systems has been identified in many countries worldwide. Concentrations higher than 0.01mg/L are detrimental to human health. We examined potential consequences for As contamination of freshwater resources based on hydrogeochemical investigations of geothermal waters in deep wells and hot springs collected from western Anatolia, Turkey. We analyzed samples for major ions and trace element concentrations. Temperature of geothermal waters in deep wells showed extreme ranges (40 and 230°C), while, temperature of hot spring fluids was up to 90°C. The Piper plot illustrated two dominant water types: Na-HCO3 - type for geothermal waters in deep wells and Ca-HCO3 - type for hot spring fluids. Arsenic concentration ranged from 0.03 to 1.5mg/L. Dominance of reduced As species, i.e., As(III), was observed in our samples. The Eh value ranged between -250 and 119mV, which suggests diverse geochemical conditions. Some of the measured trace elements were found above the World Health Organization guidelines and Turkish national safe drinking water limits. The variation in pH (range: 6.4-9.3) and As in geothermal waters suggest mixing with groundwater. Mixing of geothermal waters is primarily responsible for contamination of freshwater resources and making them unsuitable for drinking or irrigation.

  • 11. Caceres Choque, Luis Fernando
    et al.
    Ramos Ramos, Oswaldo E.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Valdez Castro, Sulema N.
    Choque Aspiazu, Rigoberto R.
    Choque Mamani, Rocio G.
    Fernandez Alcazar, Samuel G.
    Sracek, Ondra
    Bhattacharya, Prosun
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Fractionation of heavy metals and assessment of contamination of the sediments of Lake Titicaca2013Ingår i: Environmental Monitoring & Assessment, ISSN 0167-6369, E-ISSN 1573-2959, Vol. 185, nr 12, s. 9979-9994Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Chemical weathering is one of the major geochemical processes that control the mobilization of heavy metals. The present study provides the first report on heavy metal fractionation in sediments (8-156 m) of Lake Titicaca (3,820 m a.s.l.), which is shared by the Republic of Peru and the Plurinational State of Bolivia. Both contents of total Cu, Fe, Ni, Co, Mn, Cd, Pb, and Zn and also the fractionation of these heavy metals associated with four different fractions have been determined following the BCR scheme. The principal component analysis suggests that Co, Ni, and Cd can be attributed to natural sources related to the mineralized geological formations. Moreover, the sources of Cu, Fe, and Mn are effluents and wastes generated from mining activities, while Pb and Zn also suggest that their common source is associated to mining activities. According to the Risk Assessment Code, there is a moderate to high risk related to Zn, Pb, Cd, Mn, Co, and Ni mobilization and/or remobilization from the bottom sediment to the water column. Furthermore, the Geoaccumulation Index and the Enrichment Factor reveal that Zn, Pb, and Cd are enriched in the sediments. The results suggest that the effluents from various traditional mining waste sites in both countries are the main source of heavy metal contamination in the sediments of Lake Titicaca.

  • 12. Cole, S. G.
    et al.
    Kinell, G.
    Söderqvist, T.
    Håkansson, Cecilia
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Miljöstrategisk analys (fms).
    Hasselström, L.
    Izmalkov, S.
    Mikkelsen, E.
    Noring, M.
    KTH.
    Sandberg, A.
    Sjöberg, E.
    Soutukorva, Å.
    Franzén, F.
    Khaleeva, Y.
    Arctic games: An analytical framework for identifying options for sustainable natural resource governance2016Ingår i: The Polar Journal, ISSN 2154-896X, E-ISSN 2154-8978, Vol. 6, nr 1Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Changes in the Arctic are fuelled by a variety of drivers, including global warming, economic growth, improved access to natural resources, technological advances and globalisation processes. Further, the region is characterised by a diverse set of international agreements, national legislations and common pool resources. This presents challenges for actors to suggest, evaluate and agree on sustainable development alternatives. We propose an analytical framework to better understand (1) the types of trade-offs associated with Arctic futures and (2) actors’ incentives for strategic behaviour. In the framework, game theory illuminates incentives and strategies among actors, cost-benefit analysis and economic valuation of ecosystem services help identify socially desirable outcomes and institutional analysis provides insight on how governance structures can support or interfere with policy intervention. We apply the proposed framework by analysing possible oil development futures for Lofoten in Northern Norway. For example, institutional analysis and estimates of costs and benefits of reducing oil spill risk and their distribution among actors are used for discussing incentive structures, including the use of side payments as a mechanism to mitigate conflicting interests. 

  • 13.
    Earon, Robert
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Dehkordi, Seyed Emad
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Olofsson, Bo
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Groundwater Resources Potential in Hard Rock Terrain: A Multivariate Approach2014Ingår i: Ground Water, ISSN 0017-467X, E-ISSN 1745-6584Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Groundwater resources are limited and difficult to predict in crystalline bedrock due to heterogeneity and anisotropy in rock fracture systems. Municipal-level governments often lack the resources for traditional hydrogeological tests when planning for sustainable use of water resources. A new methodology for assessing groundwater resources potential (GRP) based on geological and topographical factors using principal component analysis (PCA) and analysis of variance (ANOVA) was developed and tested. ANOVA results demonstrated statistically significant differences in classed variable groups as well as in classed GRP scores with regard to hydrogeological indicators, such as specific capacity (SC) and transmissivity. Results of PCA were used to govern the weight of the variables used in the prediction maps. GRP scores were able to identify 79% of wells in a verification dataset, which had SC values less than the total dataset median. GRP values showed statistically significant correlations using both parametric (using transformed datasets) and non-parametric methods. The method shows promise for municipal or regional level planning in crystalline terrains with high levels of heterogeneity and anisotropy as a hydrogeologically and statistically based tool to assist in assessing groundwater resources. The methodology is executed in a geographic information systems environment, and uses often readily available data, such as geological maps, feature maps and topography, and thus does not require expensive and time-consuming aquifer tests.

  • 14.
    Eshagh, Mehdi
    et al.
    Department of Engineering Science, University West, Trollhättan, Sweden .
    Bagherbandi, Mohammad
    Faculty of Engineering and Sustainable Development University of Gävle.
    Combined Moho Estimators2014Ingår i: Geodynamics Research International Bulletin, E-ISSN 2345-4997, Vol. 1, nr 3Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this study, we develop three estimators to optimally combine seismic and gravimetric models of Moho surface. The first estimator combines them by their special harmonic coefficients; the second one uses the spherical harmonic coefficients of the seismic model and use integral formula for the gravimetric one. The kernel of the integral terms of this estimator shows that a cap size of 20◦ is required for the integration, but since this integral is presented to combine the low frequencies of the gravimetric model, a low resolution model is enough for the integration. The third estimator uses the gravity anomaly and converts its low frequencies to those of the gravimetric Moho model, meanwhile combining them with those of seismic one. This integral requires an integration domain of 30◦ for the gravity anomalies but since the maximum degree of this kernel is limited to a specific degree, the use of its spectral form is recommended. The kernel of the integral involving the gravity anomalies, developed for recovering high frequencies of Moho, is written in a closed-from formula and its singularity is investigated. This kernel is well-behaving and decreases fast, meaning that it is suitable for recovering the high frequencies of the Moho surface.

  • 15.
    Fan, Hongchao
    et al.
    Department of Cartography, Technical University of Munich.
    Mao, Bo
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik och Geodesi.
    Meng, Liqiu
    Department of Cartography, Technical University of Munich.
    An automatic approach for the typification of façade structuresIngår i: ISPRS journal of photogrammetry and remote sensing (Print), ISSN 0924-2716, E-ISSN 1872-8235Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    Typification is a well-established operator of map generalization. Although it is widely used in many existing research fields, less discussion has been devoted to the quality of typification. This paper presents a user survey for the evaluation of different typification results of façade structures under different constraints. The survey shows that preservation of the shape of the features is the most important constraint for a reasonable typification process, which has also been quantitatively verified by calculating the similarities between the typified façades and the original façade using attributed relational graph (ARG) and nested earth mover’s distance (NEMD) algorithms. Based on that, an algorithm is developed to generate perceivably reasonable representation from the original facade with decreasing map scale. The algorithm is implemented and tested on a number of façades. Experiments reveal that the typification can be automatically conducted and can create results which are well associated with the original façades.

  • 16.
    Gashu Adam, Achamyeleh
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Fastigheter och byggande, Fastighetsvetenskap.
    Land Tenure in the Changing Peri-Urban Areas of Ethiopia: The Case of Bahir Dar City2014Ingår i: International Journal of Urban and Regional Research, ISSN 0309-1317, E-ISSN 1468-2427, Vol. 38, nr 6, s. 1970-1984Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ethiopia's urban expansion and development strategy has been based on the acquisition of land by government from adjacent peri-urban areas. The land in the peri-urban areas is predominantly agricultural in nature, and it has been held by local farmers or landholders. This article aims to examine the nature of urban expansion and development from the perspective of the land rights of the local peri-urban landholders. To achieve this purpose, it has employed a case-study approach. As urban territory extends into adjacent peri-urban areas, the land rights of local landholders are expected to be automatically cancelled and transferred to people who can pay for a lease. This shows that very little attention is paid to the land rights of local landholders in peri-urban areas in the process of urban expansion and development. Therefore, it is not difficult to imagine that local landholders in those areas have a prevailing sense of insecurity about their land.

  • 17.
    Gashu Adam, Achamyeleh
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Fastigheter och byggande, Fastighetsvetenskap.
    Peri-Urban Land Rights in the Era of Urbanisation in Ethiopia: A Property Rights Approach2014Ingår i: African Review of Economics and Finance, ISSN 2042-1478, E-ISSN 2410-4906, Vol. 6, nr 1, s. 120-138Artikel i tidskrift (Refereegranskat)
  • 18.
    Haas, Tigran
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Urbana och regionala studier.
    Sustainable Urbanism and Beyond: Rethinking Cities for the Future2012Samlingsverk (redaktörskap) (Refereegranskat)
  • 19.
    Haas, Tigran
    et al.
    KTH, Tidigare Institutioner, Infrastruktur.
    Roberts, Andrew
    Hifab International AB.
    Opportunities for Sustaining Human Settlements in a Post-Conflict War Zone: The Case of Bosnia and Herzegovina1999Ingår i: Open House International, ISSN 0168-2601, Vol. 24, nr 1, s. 54-65Artikel i tidskrift (Refereegranskat)
  • 20.
    Halder, Dipti
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Arsenic Exposure Risk from Rice and Other Dietry Components in Rural Bengal2013Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This study investigates the risk of arsenic (As) exposure from staple diet to the communities in rural Bengal, even when they have been supplied with As safe drinking water. The results indicate that average accumulation of As in rice grain increases with decrease of grain size [extra-long slender (ELS): 0.04 mg kg-1; long slender (LS): 0.10 mg kg-1; medium slender (MS): 0.16 mg kg-1 and short bold (SB): 0.33 mg kg-1], however people living in the rural villages mostly prefer brown colored SB type of rice because of its lower cost. Among the vegetables generally consumed in rural villages, the accumulation of As is highest in the leafy type of vegetables (0.21 mg kg-1), compared to non-leafy (0.07 mg kg-1) and root  vegetables (0.10 mg kg-1). Arsenic predominantly accumulates in rice (>90%) and vegetables (almost 100%) in inorganic species [As(III & V)]. The estimates of exposure via dietary and drinking water routes show that when people are consuming water with As concentration <10 μg L-1, the total daily intake of inorganic As (TDI-iAs) exceeds the previous provisional tolerable daily intake (PTDI) value of 2.1 μg day-1 kg-1 BW, recommended by World Health Organization (WHO) in 35% of the cases due to consumption of rice. Considerably high concentration of As in urine and saliva despite drinking of As safe water (<10 μg L-1) further supports that dietary intake of As, mainly through consumption of rice could be alternative pathway of As exposure among the population. When the level of As concentration in drinking water is above 10 μg L-1, the TDI-iAs exceeds the previous  PTDI for all the participants. These results imply that when rice consumption is a significant contributor to the TDI-iAs, supplying water with As concentration at current national drinking water standard for India and Bangladesh (50 μg L-1) would place many people above the safety threshold of PTDI. When As concentration in drinking water exceeds 50 μg L-1 As exposure through drinking water largely predominates over the exposure through dietary intake. It is found that the consumption of vegetables in rural Bengal does not pose  significant health threat to the population independently. It is also revealed that cooking of rice with high volume of As safe (<10 μg L-1) water can decrease both total and inorganic As content in cooked rice. However, the assessment of As exposure risk indicates that despite such lowering in As concentrations, still consumption of cooked rice is a significant pathway of As exposure to the population in rural Bengal. This study suggests that any effort to mitigate the As exposure of the villagers in Bengal must consider the risk of As exposure from rice consumption together with drinking water.

  • 21.
    Hammar, Torun
    et al.
    Swedish Univ Agr Sci SLU, Dept Energy & Technol, SE-75007 Uppsala, Sweden..
    Stendahl, Johan
    SLU, Dept Soil & Environm, SE-75007 Uppsala, Sweden..
    Sundberg, Cecilia
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik.
    Holmström, Hampus
    SLU, Dept Forest Resource Management, SE-90183 Umea, Sweden..
    Hansson, Per-Anders
    Swedish Univ Agr Sci SLU, Dept Energy & Technol, SE-75007 Uppsala, Sweden..
    Climate impact and energy efficiency of woody bioenergy systems from a landscape perspective2019Ingår i: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 120, s. 189-199Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The climate impact of bioenergy is debated, especially due to potential land use change effects and biogenic carbon fluxes. This study assessed the climate impact and energy efficiency of conventional long-rotation forest residues (branches, tops and stumps) and short-rotation forestry (willow) from a landscape perspective. A time-dependent life cycle assessment method, which considers the timing of biogenic carbon fluxes and the impact on global temperature over time, was combined with GIS mapping to assess the impact for a specific Swedish region (Uppsala County), i.e. a 'real' landscape. The results showed that harvesting forest residues decreased the forest carbon stocks over the landscape, while growing willow on previous fallow land increased the total carbon stocks. On average, energy ratios of 49 MJ MJ(-1) for branches and tops, and 30 MJ MJ(-1) for stumps and willow was found. Harvesting forest residues from the studied landscape resulted in climate impacts of around 0.8.10(-15) K MJ(-1) heat for branches and tops, and 1.3.10(-15) K MJ(-1) heat for stumps. Willow energy gave the lowest climate impact of about -0.6,10(-15) K MJ(-1) heat. The landscape analysis showed that spatial variations in the region had an effect on energy efficiency and climate impact, but that this effect was relatively small. A more important factor was the time frame chosen for the analysis, especially for long-rotation forest systems. Methodological choices such as spatial scale (stand or landscape perspective), allocation method and functional unit also influenced the results.

  • 22.
    Hedblom, Marcus
    et al.
    Department of Swedish Forest Resource Management, Swedish University of Agricultural Sciences.
    Andersson, Erik
    Stockholm Resilience Centre, Stockholm University.
    Borgström, Sara
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik. Stockholms universitet, Stockholm Resilience Centre.
    Flexible land-use and undefined governance: From threats to potentials in peri-urban landscape planning2017Ingår i: Land use policy, ISSN 0264-8377, E-ISSN 1873-5754, Vol. 63, s. 523-527Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Densification of cities is presently one of the dominating strategies for urbanization globally. However, how densification of cities is linked to processes in the peri-urban landscapes is rather unknown. The aim of this paper is to highlight the potentials in of peri-urban landscapes to be recognized as complementary providers of urban ecosystem services when green areas in cities are reduced by densification. We suggest that the way forward is to change the perceptions of peri-urban areas from being defined as located between cities and rural areas with a specific population density or a geographical distance, to become recognized as a landscape defined by its functionality. By identifying and describing the functionality in peri-urban landscapes the existing governance gaps can be recognized and thus dealt with through adaptation of existing planning tools. Although not yet articulated, peri-urban areas should be used to facilitate integration of top down and bottom up approaches and thereby closing the governance gaps. We illustrate this reasoning by two examples; one of the establishment of green wedges in Stockholm, Sweden, and the other with the establishments of international Model forests. We conclude that further densification of cities will create a lack of ecosystem services in cities by putting an even higher pressure on the peri-urban landscape and not as suggested today that densification lower pressure on peri-urban landscapes. Rethinking and reframing the peri-urban areas by adapting existing platforms will potentially contribute to a more nuanced discussion on strategies for urban development generally.

  • 23. Hoinkis, J.
    et al.
    Islam, R.
    Akhtarul Islam, M.
    Korejba, W.
    Ding, D.
    Bundschuh, Jochen
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630). Karlsruhe University of Applied Sciences, Karlsruhe, Germany .
    Energy-efficient small-scale reverse osmosis units - A promising approach for arsenic removal from drinking water2010Ingår i: Arsenic in Geosphere and Human Diseases, As 2010 - 3rd International Congress: Arsenic in the Environment, 2010, s. 429-430Konferensbidrag (Refereegranskat)
  • 24. Hossain, M.
    et al.
    Mainul Islam, M.
    Rashid, S. M. A.
    Moklesur Rahman, M.
    Rahman, M.
    Sultana, S.
    Ahmed, K. M.
    Aziz Hasan, M.
    Bhattacharya, Prosun
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630).
    Jacks, Gunnar
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630).
    Thunvik, Roger
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630).
    Von Brömssen, M.
    Delimiting the shallow aquifer characteristics using Vertical Electric Soundings (VES) and hydrochemical variability in a region with high arsenic groundwater in southeastern Bangladesh2010Ingår i: Arsenic in Geosphere and Human Diseases, As 2010 - 3rd International Congress: Arsenic in the Environment, 2010, s. 105-107Konferensbidrag (Refereegranskat)
  • 25. Innocenti, M. E.
    et al.
    Cazzola, E.
    Mistry, R.
    Eastwood, J. P.
    Goldman, M. V.
    Newman, D. L.
    Markidis, Stefano
    KTH, Skolan för datavetenskap och kommunikation (CSC), Beräkningsvetenskap och beräkningsteknik (CST).
    Lapenta, G.
    Switch-off slow shock/rotational discontinuity structures in collisionless magnetic reconnection: What to look for in satellite observations2017Ingår i: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 44, nr 8, s. 3447-3455Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In Innocenti et al. (2015) we have observed and characterized for the first time Petschek-like switch-off slow shock/rotational discontinuity (SO-SS/RD) compound structures in a 2-D fully kinetic simulation of collisionless magnetic reconnection. Observing these structures in the solar wind or in the magnetotail would corroborate the possibility that Petschek exhausts develop in collisionless media as a result of single X point collisionless reconnection. Here we highlight their signatures in simulations with the aim of easing their identification in observations. The most notable signatures include a four-peaked ion current profile in the out-of-plane direction, associated ion distribution functions, increased electron and ion anisotropy downstream the SS, and increased electron agyrotropy downstream the RDs.

  • 26.
    Jacks, Gunnar
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630).
    Mörth, M.
    Slejkovec, Z.
    Arsenic uptake by flora and fauna in northern Sweden2010Ingår i: Arsenic in Geosphere and Human Diseases, As 2010 - 3rd International Congress: Arsenic in the Environment, 2010, s. 187-188Konferensbidrag (Refereegranskat)
  • 27.
    Joud, Seyed Mehdi Shafiei
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och satellitpositionering.
    Contributions of Satellite Geodesy to Post-Glacial Rebound Research2018Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Glacial Isostatic Adjustment (GIA) is a global and long-term process in the Earth, which began 21.5 millennia ago, according to many ice history modellers. One way to understand the processes of the Earth’s interior, the crustal deformation, and a key correction to estimate the climatological parameters is obtained by studying GIA.

    Our main objectives are to improve the gravimetric GIA modelling by utilizing some of the satellite geodesy missions leading to the land uplift and geoid rate models and to determine the geoid depression due to GIA. The isostatic rebound of the solid Earth is observable in some regions, e.g. in Fennoscandia, North America and Greenland, using some geodetic techniques, such as GPS. In view of physical geodesy, the mantle mass flow in the GIA process perturbs the observed gravity from a hypothetic isostatic state, which can be measured using satellite gravimetry techniques. We will extract the static and temporal gravity signals due to GIA from satellite gravimetry and present a mathematical relation to determining the solid Earth vertical movement due to GIA leading to gravimetric and combined land uplift rate models.

    We use an Earth Gravitational Model (EGM) determined from a number of satellite missions to produce regional geoid models and remove the perturbing effect of the crustal variation and topography from the geoid height resulting in topographic-isostatic geoid models. Then the geoid height signal due to GIA will be extracted using a spectral window and a multiple regression analysis. In North America and Fennoscandia, we find that maximum depressions of  13.8 and 9.2 m of the topographic-isostatic geoid model, respectively, are due to GIA.

    Using some analysing methods, a number of high-resolution regional gravimetric modelling methods have been investigated with respect to their compatibility with the GPS data and the data from the GIA forward models. We determine the GIA signal of the temporal geoid change by exploiting the monthly gravity field from Gravity Recovery And Climate Experiment (GRACE) satellite mission and investigate the capability of three mathematical methods, namely regression, principal component, and independent component analysis (ICA) in extracting the secular trend of the GRACE monthly gravity data. One of the results of this investigation is the success of the ICA method relative to the other methods of gravimetric modelling.

    Finally, we present a least squares combined Land Uplift rate Model (LUM) by assimilating the data from GPS and the gravimetric model, determined using the ICA method, into the GIA forward model and compare it with a recent GIA forward model, namely ICE-6G_C (Peltier et al. 2015). Their discrepancies, for the whole areas subject to epeirogeny in North America and Fennoscandia, vary from -1.8 to +3.3, and -0.45 to +0.75 mm/a, respectively, while for the areas near the centre of the uplifting regions these two models are shown to be in a complete agreement.

  • 28. Karlsson, Hanna L.
    et al.
    Gliga, Anda R.
    Calleja, Fabienne M. G. R.
    Goncalves, Catia S. A. G.
    Odenevall Wallinder, Inger
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Vrieling, Harry
    Fadeel, Bengt
    Hendriks, Giel
    Mechanism-based genotoxicity screening of metal oxide nanoparticles using the ToxTracker panel of reporter cell lines2014Ingår i: Particle and Fibre Toxicology, ISSN 1743-8977, E-ISSN 1743-8977, Vol. 11, s. 41-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: The rapid expansion of manufacturing and use of nano-sized materials fuels the demand for fast and reliable assays to identify their potential hazardous properties and underlying mechanisms. The ToxTracker assay is a recently developed mechanism-based reporter assay based on mouse embryonic stem (mES) cells that uses GFP-tagged biomarkers for detection of DNA damage, oxidative stress and general cellular stress upon exposure. Here, we evaluated the ability of the ToxTracker assay to identify the hazardous properties and underlying mechanisms of a panel of metal oxide-and silver nanoparticles (NPs) as well as additional non-metallic materials (diesel, carbon nanotubes and quartz). Methods: The metal oxide-and silver nanoparticles were characterized in terms of agglomeration and ion release in cell medium (using photon cross correlation spectroscopy and inductively coupled plasma with optical emission spectroscopy, respectively) as well as acellular ROS production (DCFH-DA assay). Cellular uptake was investigated by means of transmission electron microscopy. GFP reporter induction and cytotoxicity of the NPs was simultaneously determined using flow cytometry, and genotoxicity was further tested using conventional assays (comet assay, gamma-H(2)AX and RAD51 foci formation). Results: We show that the reporter cells were able to take up nanoparticles and, furthermore, that exposure to CuO, NiO and ZnO nanoparticles as well as to quartz resulted in activation of the oxidative stress reporter, although only at high cytotoxicity for ZnO. NiO NPs activated additionally a p53-associated cellular stress response, indicating additional reactive properties. Conventional assays for genotoxicity assessment confirmed the response observed in the ToxTracker assay. We show for CuO NPs that the induction of oxidative stress is likely the consequence of released Cu ions whereas the effect by NiO was related to the particles per se. The DNA replication stress-induced reporter, which is most strongly associated with carcinogenicity, was not activated by any of the tested nanoparticles. Conclusions: We conclude that the ToxTracker reporter system can be used as a rapid mechanism-based tool for the identification of hazardous properties of metal oxide NPs. Furthermore, genotoxicity of metal oxide NPs seems to occur mainly via oxidative stress rather than direct DNA binding with subsequent replication stress.

  • 29. Kiamehr, R.
    et al.
    Eshagh, Mehdi
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Transporter och samhällsekonomi (stängd 20110301), Geodesi (stängd 20110301).
    EGMlab, a scientific software for determining the gravity and gradient components from global geopotential models2008Ingår i: Earth Science Informatics, ISSN 1865-0473, Vol. 1, nr 2, s. 93-103Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Nowadays, Global Geopotential Models (GGMs) are used as a routine stage in the procedures to compute a gravimetric geoid. The GGMs based geoidal height also can be used for GPS/levelling and navigation purposes in developing countries which do not have accurate gravimetric geoid models. Also, the GGM based gravity anomaly including the digital elevation model can be used in evaluation and outlier detections schemes of the ground gravity anomaly data. Further, the deflection of vertical and gravity gradients components from the GGMs can be used for different geodetic and geophysical interpretation purposes. However, still a complete and user-friendly software package is not available for universities and geosciences communities. In this article, first we review the procedure for determination of the basic gravity field and gradient components from the GGMs, then general MATLAB based software is presented and applied as a sample case study for determination of gravity components based on the most recent EIGEN-GL04C GRACE model in Sweden.

  • 30.
    Kourtit, Karima
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Urbana och regionala studier. KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centrum för framtida stadsrum.
    Nijkamp, P.
    Suzuki, S.
    Are global cities sustainability champions?: A double delinking analysis of environmental performance of urban agglomerations2020Ingår i: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 709, artikel-id 134963Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Urban agglomerations – irrespective of their size or location – may act not only as engines of economic growth, but also as vehicles of environmental and climate sustainability that may stimulate both socio-economic achievements and environmentally-benign outcomes. Clearly, the efficiency of these outcomes may differ for different types of urban agglomeration in the world. This paper aims to present and test an advanced methodology for assessing economic and sustainability-oriented performance strategies for global cities, by developing and applying a super-efficient Data Envelopment Analysis (DEA) model. We compare 40 global cities – included in the Global Power City Index (GPCI) database – in a benchmark study in order to trace the highest-performing urban regions from both an economic and environmental-climatological efficiency perspective, by applying relevant quantitative GPCI indicators to these 40 cities. Our ultimate goal is to test what is termed the ‘delinking’ hypothesis, from the viewpoint of both economic prosperity and urban size externalities. This approach will be applied empirically by examining the GPCI data set comprised of various multi-dimensional and empirically verified indicators on economic performance and climatological-environmental conditions for the 40 global cities concerned. We regard both the size of these agglomerations and their economic welfare position as critical parameters for assessing their economic and environmental efficiency performance. In the framework of our original DEA approach, these urban areas are categorised according to 2x2 dimensions, viz. in terms of both agglomeration size (big or medium-sized) and the economic development level of the area (highly developed or developing/emerging). Our contribution serves to assess – by means of regression techniques – the highest performing agglomerations among the urban sustainability champions on the basis of the two above-mentioned assessment criteria. This approach provides the opportunity to test the so-called Kuznets sustainability curve under two different conditions, viz. agglomeration size and economic development. The study presents and interprets the empirical findings for these four classes of global cities.

  • 31.
    Kuttuva Rajarao, Gunaratna
    et al.
    KTH, Skolan för bioteknologi (BIO), Bioprocessteknik (stängd 20130101).
    Shokri, Atefeh
    KTH, Skolan för bioteknologi (BIO), Bioprocessteknik (stängd 20130101).
    Bhattacharya, Prosun
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630).
    Jacks, Gunnar
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630).
    Bundschuh, Jochen
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630).
    Von Brömssen, M.
    Microbial characterization of Holocene alluvial sediments in the Meghna Flood Plain of Matlab Upazila, Bangladesh2010Ingår i: Arsenic in Geosphere and Human Diseases, As 2010 - 3rd International Congress: Arsenic in the Environment, 2010, s. 140-142Konferensbidrag (Refereegranskat)
  • 32.
    Li, Xiaodong
    et al.
    Department of Chemistry,P.O. Box 55, FI-00014University of Helsinki, Finland.
    Meng, Shuo
    Puhakka, Eini
    Department of Chemistry,P.O. Box 55, FI-00014University of Helsinki, Finland.
    Ikonen, Jussi
    Department of Chemistry,P.O. Box 55, FI-00014University of Helsinki, Finland.
    Liu, Longcheng
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Siitari-Kauppi, Marja
    Department of Chemistry,P.O. Box 55, FI-00014University of Helsinki, Finland.
    A modification of the electromigration device and modelling methods for diffusion and sorption studies of radionuclides in intact crystalline rocks.2019Ingår i: Journal of Contaminant Hydrology, ISSN 0169-7722, E-ISSN 1873-6009Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    To determine the diffusion and sorption propertiesof radionuclides in intact crystalline rocks, a newelectromigration devicewas built and tested by running with I-and Se(IV) ions. By introducing a potentiostatto impose a constant voltageover the studied rock sample, the electromigration device cangive more stable and accurateexperimental resultsthan those from the traditional electromigration devices.In addition, the variation in the pHofthe background electrolytes wasminimised by adding a small amount of NaHCO3as buffers.To interpret the experimental results with moreconfidence, anadvection-dispersion model was also developed in thisstudy, which accounts for the most important mechanisms governing ionic transport in the electromigration experiments.Data analysis of the breakthrough curves by the advection-dispersion model, instead of the traditional ideal plug-flowmodel,suggest that the effective diffusivitiesof I-and Se(IV)are (1.15±0.06) ×10-13m2/s and (3.50±0.86) ×10-14m2/s, respectively. The results also show thatI-is more mobile than Se(IV) ions when migrating through the sameintact rock sampleand that theirsorption properties are almost identical.

  • 33.
    Lidström, Susanna
    et al.
    Filosofi och historia, KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Filosofi och teknikhistoria, Historiska studier av teknik, vetenskap och miljö.
    Johnson, Andrew F.
    Ecosystem-based fisheries management: a perspective on the critique and development of the concept2019Ingår i: Fish and Fisheries, ISSN 1467-2960, E-ISSN 1467-2979Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The concept of ecosystem‐based fisheries management (EBFM) has been subjected to debate since it was introduced in the late 1990s. The development of the concept seems to follow two separate but simultaneous trajectories of increased popularity but also sustained critique. This paper offers an analysis of potential mechanisms behind these disparate trajectories by drawing on a theoretical framework from science and technology studies (STS) centred around "black box" and actor‐network theory. To support our analysis, we perform an exploratory literature review of how the EBFM concept has been used in a selection of high impact fisheries research papers. We find that the popularity of EBFM does not guarantee its integrity, usefulness or analytical insight, but also that persistent critique of how the concept is used seems to be driving some change. We think that a continued trajectory of increased understanding, contextualization and discernibility of EBFM can help overcome the considerable ambiguity associated with the concept and make it increasingly useful to fisheries management. This means moving away from routine use of the term towards a practicable and tangible approach to improve fisheries sustainability.

  • 34. Lina, Nordin
    et al.
    Riehm, Mats
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630), Biogeofysik.
    Gustavsson, Torbjörn
    Bogren, Jörgen
    Road surface wetness variations: Measurements and effects for winter road maintenance2013Ingår i: Journal of transportation engineering, ISSN 0733-947X, E-ISSN 1943-5436, Vol. 139, nr 8, s. 787-796Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Road wetness is a critical parameter when it comes to preventing road slipperiness. It has so far been difficult to measure, but new measurement techniques on the market make it useful to investigate the savings opportunities within road maintenance operations. The present study tests a new sensor mounted on a road maintenance vehicle run in a maintenance district in central Sweden. The sensor that measures road surface water depth is connected to a global positioning system (GPS) system and a global system for mobile communications (GSM) phone modem. Potential savings are calculated based on the measured road surface water depth and on the amount of applied salt needed to lower the freezing point to a certain degree. The results indicate variations in water depth along the measured roads, which implies that the salt concentrations along the roads could also vary. Though the variations were smaller along the tested highway, the calculated savings could still be up to 22%. Despite the many assumptions made in the calculations, considerable savings could potentially be realized by applying such wetness measurements.

  • 35.
    Lind, Bo
    et al.
    Swedish Geotechnical Institute, SGI.
    Larsson, L.
    Gustafsson, Jon-Petter
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630), Miljögeokemi och ekoteknik.
    Gustafsson, David
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630), Biogeofysik.
    Ohlsson, Susanna
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630), Miljögeokemi och ekoteknik.
    Norrman, J.
    Arvidsson, O.
    Arm, M.
    Energiaska som vägbyggnadsmaterial - utlakning och miljöbelastning från en provväg2005Rapport (Övrigt vetenskapligt)
  • 36.
    LIU, RUI
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Travel Diary Semantics Enrichment of Trajectoriesbased on Trajectory Similarity Measures2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Trajectory data is playing an increasingly important role in our daily lives, as well as in commercial applications and scientific research. With the rapid development andpopularity of GPS, people can locate themselves in real time. Therefore, the users’behavior information can be collected by analyzing their GPS trajectory data, so as topredict their new trajectories’ destinations, ways of travelling and even thetransportation mode they use, which forms a complete personal travel diary. The taskin this thesis is to implement travel diary semantics enrichment of user’s trajectoriesbased on the historical labeled data of the user and trajectory similarity measures.Specially, this dissertation studies the following tasks: Firstly, trip segmentationconcerns detecting the trips from trajectory which is an unbounded sequence oftimestamp locations of the user. This means that it is important to detect the stops,moves and trips of the user between two consecutive stops. In this thesis, a heuristicrule is used to identify the stops. Secondly, tripleg segmentation concerns identifyingthe location / time instances between two triplegs where / when a user changesbetween transport modes in the user's trajectory, also called makes transport modetransitions. Finally, mode inference concerns identifying travel mode for each tripleg.Specially, steps 2 and 3 are both based on the same trajectory similarity measure andproject the information from the matched similar trip trajectory onto the unlabeled triptrajectory. The empirical evaluation of these three tasks is based on real word data set(contains 4240 trips and 5451 triplegs with 14 travel modes for 206 users using oneweek study period) and the experiment performance (including trends, coverage andaccuracy) are evaluated and accuracy is around 25% for trip segmentation; accuracyvaries between 50% and 55% for tripleg segmentation; for mode inference, it isbetween 55% and 60%. Moreover, accuracy is higher for longer trips than shortertrips, probably because people have more mode choices in short distance trips (likemoped, bus and car), which makes the measure more confused and the accuracy canbe increased by nearly 10% with the help of reverse trip identifiable, because it makesa trip have more similar historical trips and increases the probability that a newunlabeled trip can be matched based on its historical trips.

  • 37. McConville, Jennifer
    et al.
    Kain, Jaan-Henrik
    Kvarnström, Elisabeth
    Renman, Gunno
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630), Miljögeokemi och ekoteknik.
    Bridging sanitation engineering and planning: theory and practice in Burkina Faso2011Ingår i: Journal of Water Sanitation and Hygiene for Development, ISSN 2043-9083, Vol. 1, nr 3, s. 205-212Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The global challenge of providing sanitation services to the un-served underlines a need to change the way in which sanitation planning and service provision is approached. This paper offers a framework for categorizing sanitation projects planning processes based on planning steps and procedural planning theory to help engineers and sanitation planners gain a deeper understanding of the dynamics of these processes. The analysis identifies and discusses trends in both guidelines and actual sanitation programs. The results show that contemporary sanitation planning guidelines and field projects utilize patchwork processes of different planning modes, although the step of designing options is dominated by an expert-driven, rational-comprehensive approach. The use of planning theory can help engineers to ask critical questions about the objectives of the planning process and to develop context-appropriate planning processes that will make a difference for improving sanitation service provision.

  • 38.
    Meng, Shuo
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Li, Xiaodong
    Siitari-Kauppi, Marja
    Liu, Longcheng
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik.
    Development and application of an advection-dispersion model for data analysis of electromigration experiments with intact rock coresManuskript (preprint) (Övrig (populärvetenskap, debatt, mm))
  • 39. Mileriene, Rosita
    et al.
    Gulbinskas, Saulius
    Sustainable development indicators for the coastal zone management2012Ingår i: Proceedings of the 2nd International Symposium of Integrated Coastal Zone Management / [ed] E. Moksness, E. Dahl & J. Støttrup, Wiley-Blackwell, 2012Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Increasing pressure on coastal areas arising from more intensive marine use stimulates conflicts among different stakeholders in coastal regions. Different demands in using land and marine coastal components need to be balanced in a multi sectoral perspective. Therefore application of ICZM principles seems to be the optimal economical and legal instrument for minimising possibilities of conflicts. 27 sustainable development indicators, established by EU have been widely applied for ICZM in many European coastal regions. Indicatorbased approach to evaluating coastal zone development allows to make comparisons between different coastal regions as well as between coastal zone and hinterland. Such approach also has to provide the reliable information on state of the coastal zone in each separate region, thus supporting the quality of coastal management decisions. The Sustainable Development indicators for ICZM (SDI‐4‐SEB) in the South‐Eastern Baltic region project was carried out in order to assess the state of the coastal zone using EU recommended set of indicators. Analysed indicators are the signpoins, describing the current state of the coastal zone management. Also being interconnected to each other indicators have the additional value when speaking about understanding such a complex system as the coastal zone. However, project implementation revealed that sustainable development indicators may require some improvements and adaptation to regional specifics. Insufficient data, imprecise requirements or lack of national regulations suggested to revise the chosen indicator’s set and to think about the development of more region specific indicators, also reserving the possibility of benchmarking EU coastal regions.

  • 40. Neidhardt, H.
    et al.
    Berner, Z.
    Freikowski, D.
    Biswas, Ashis
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Mark- och vattenteknik.
    Winter, J.
    Chatterjee, D.
    Norra, S.
    Influences of groundwater extraction on the distribution of dissolved As in shallow aquifers of West Bengal, India2013Ingår i: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 262, s. 941-950Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Here we report temporal changes of As concentrations in shallow groundwater of the Bengal Delta Plain (BDP). Observed fluctuations are primarily induced by seasonally occurring groundwater movement, but can also be connected to anthropogenic groundwater extraction. Between December 2009 and July 2010, pronounced variations in the groundwater hydrochemistry were recorded in groundwater samples of a shallow monitoring well tapping the aquifer in 22-25m depth, where Astot concentrations increased within weeks from 100 to 315μgL-1. These trends are attributed to a vertically shift of the hydrochemically stratified water column at the beginning of the monsoon season. This naturally occurring effect can be additionally superimposed by groundwater extraction, as demonstrated on a local scale by an in situ experiment simulating extensive groundwater withdrawal during the dry post-monsoon season. Results of this experiment suggest that groundwater extraction promoted an enduring change within the distribution of dissolved As in the local aquifer. Presented outcomes contribute to the discussion of anthropogenic pumping influences that endanger the limited and yet arsenic-free groundwater resources of the BDP.

  • 41. Nilsson, D.
    et al.
    Kaijser, Arne
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Filosofi och teknikhistoria, Historiska studier av teknik, vetenskap och miljö.
    Discrimination by Default: The post-colonial heritage of Urban water provision in east Africa2012Ingår i: Water and Sanitation Services: Public Policy and Management, Taylor and Francis , 2012, s. 275-291Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 42.
    Nyblom, Åsa
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Miljöstrategisk analys (fms). Skolan för datavetenskap och kommunikation (CSC), Centra, KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centre for Sustainable Communications, CESC.
    Making travel sustainable with ICT?: The social practice of travel planning and travel information use in everyday life2014Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Denna avhandling tar resenärens perspektiv, och undersöker från vardagslivets horisont hur resor egentligen planeras, och hur information används när de många, ofta obemärkta, vardagsresorna görs i staden. Etnografiska fältstudier i södra Stockholm, gjorda och analyserade med ett praktikteoriperspektiv, visar att människor använder sig av många olika typer av information för att planera och genomföra sina resor. Därför bör begreppet reseinformation definieras vitt nog att rymma både informella, formella, analoga och digitala typer av reseinformation. Först då är det möjligt att iaktta interaktioner mellan dessa, och också se informationens eventuella potential som förändringsfaktor för hållbart stadsresande. Även situationer när reseinformation inte används uppmärksammas och diskuteras.

    Reseplanering är i vardaglig praktik något som sker lite i taget, i mellanrummen mellan andra sysslor och aktiviteter. Det är en process mer förgrenad i tid, rum och innehåll än den avgränsade sökning efter information om bästa sättet att ta sig mellan A och B som många existerande IT-baserade reseplanerare verkar förutsätta och i dagsläget assisterar. Reseplanering är starkt knutet till den övergripande planeringen av aktiviteter i livet, och reseplanering har därför oftast ett vidare tidsspann än endast en resa. Planering av resor inkluderar även hänsyn till faktorer som nödvändiga förberedelser (saker att göra innan avfärd/ta med sig på resan); hantering av fordon och bagage i tid och rum (få hem cykeln/bilen igen eller få den säkert parkerad); vädret (nuvarande och prognostiserat); sociala relationer (potentialen för konflikter/positiv samvaro vid olika färdmedelsval); sociala normer (om gott föräldraskap eller hur man för sig på kollektiva färdmedel); och hälsoaspekter (vilja till motion eller oförmåga att gå i trappor).

    Fältarbetet gjorde tydligt att reseinformation ibland används som en snuttefilt – något att ty sig till och hålla i handen på okänt territorium tills du har kommit till målet för din resa. Reseplanering kan också, beroende på livssituation, antingen upplevas och liknas vid husbygge med prefabricerade element – samma standardiserade, välkända bitar sammanfogas på ungefär samma sätt varje gång; eller också ett korthus – om någonting ändras brakar hela huset ihop, och måste byggas upp igen med en helt annan design.

    Under de senaste decennierna har det skett en snabb utveckling av IT-lösningar på transportområdet. Olika typer av reseinformationstjänster har föreslagits som ett verktyg för att ändra resebeteenden och därmed minska transporters miljöpåverkan. Med utgångspunkt från studiens 6 empiriska insikter i hur reseplanering går till i praktiken, och hur reseinformation används blir det tydligt att morgondagens reseplanerartjänster, om de kopplades ihop med andra digitala system vi använder i vår vardag, skulle kunna utformas på ett sätt som utvidgar systemets "assistanshorisont" för att bättre passa ihop med reseplaneringspraktikerna i vår vardag. Potentialen och rollen för reseinformationstjänster och IT i arbetet med att minska transporters miljöpåverkan bör diskuteras från ett perspektiv som är kritiskt till alltför linjära och instrumentella utgångspunkter, vilket denna avhandling bidrar till.

  • 43.
    Nyblom, Åsa
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Miljöstrategisk analys (fms). Skolan för datavetenskap och kommunikation (CSC), Centra, KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centre for Sustainable Communications, CESC.
    Eriksson, Elina
    KTH, Skolan för datavetenskap och kommunikation (CSC), Medieteknik och interaktionsdesign, MID. Skolan för datavetenskap och kommunikation (CSC), Centra, KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Centra, Centre for Sustainable Communications, CESC.
    Travel information services and travel planning practice: Changing the horizon of assistanceIngår i: International Journal of Sustainable Transportation, ISSN 1556-8318, E-ISSN 1556-8334Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    Recent decades have seen rapid growth in ICT services relating to transportation. Different types of travel information services have been proposed as a means to decrease the environmental impacts of transportation through behavioural change. However, empirical evidence shows that travel planning is a fragmented, distributed and fluid process that is not as enclosed in time and space or delimited in content, as existing ICT services for travel planning would imply, despite smart and mobile solutions. This paper examines the role of planning and coordination in the travel choices of everyday life and the time horizons and decisions that are part of current travel planning services. It also considers how travel information services of tomorrow, linked with other ICT services, could be designed to stretch the horizon of assistance, in order to better support travel planning processes in everyday life. Finally, it critically discusses the role of travel information services and ICT in the work of achieving more sustainable mobility.

  • 44. Ordóñez, J. I.
    et al.
    Condori, A.
    Moreno, Luis
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk apparatteknik.
    Cisternas, L. A.
    Heap leaching of caliche ore. Modeling of a multicomponent system with particle size distribution2017Ingår i: Minerals, ISSN 2075-163X, E-ISSN 2075-163X, Vol. 7, nr 10, artikel-id 180Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Caliche is a mineral exploited in northern Chile, from which iodine and Nitrate salts (saltpeter) are obtained. This ore is the most important source of iodine in the world and is processed mainly by heap leaching using water as a leaching agent. Heap leaching of caliche ore is carried out by the stacking of ROM (Run-Of-Mine) material, where the particle size distribution covers a wide range, from a few millimeters up to several decimeters, even diameters about 1 m. During the leaching, the multiple soluble species of caliche, which can reach total fractions larger than 40%, are dissolved at different rates, mainly controlled by their solubilities. When it occurs and unlike most other leachable ores, the particle size diminishes. The leaching modeling of several soluble species of caliche has been recently addressed; however, one of the main assumptions is the idealization that the heap is composed of particles of the same size. The present work aims to complement the previously formulated phenomenological models for caliche ore leaching, through a model that considers the simultaneous dissolution of two species from caliche with three different particle sizes. These two water-soluble species have different solubilities and dissolution rates and the conceptual model considers that both species are dissolved at the particle surface. When the most soluble species is being depleted, the particle collapses, leaving a remaining fraction of the less soluble species together with insoluble material. The less soluble species is now being dissolved from the collapsed material. This article also includes the experimental verification of the conceptual model using data obtained from column leaching tests conducted for this purpose, focusing on the dissolution of two soluble species: Nitrate and Magnesium.

  • 45. Ouassou, Mohammed
    et al.
    Jensen, Anna B. O.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och satellitpositionering.
    Gjevestad, Jon Glenn Omholt
    Kristiansen, Oddgeir
    Next Generation Network Real-Time Kinematic Interpolation Segment to Improve the User Accuracy2015Ingår i: International Journal of Navigation and Observation, ISSN 1687-5990, E-ISSN 1687-6008, artikel-id 346498Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper demonstrates that automatic selection of the right interpolation/smoothing method in a GNSS-based network realtime kinematic (NRTK) interpolation segment can improve the accuracy of the rover position estimates and also the processing time in the NRTK processing center. The methods discussed and investigated are inverse distance weighting (IDW); bilinear and bicubic spline interpolation; kriging interpolation; thin-plate splines; and numerical approximation methods for spatial processes. The methods are implemented and tested using GNSS data from reference stations in the Norwegian network RTK service called CPOS.Data sets with an average baseline between reference stations of 60–70 kmwere selected. 12 prediction locations were used to analyze the performance of the interpolation methods by computing and comparing different measures of the goodness of fit such as the root mean square error (RMSE), mean square error, and mean absolute error, and also the computation time was compared. Results of the tests show that ordinary kriging with theMat´ern covariance function clearly provides the best results. The thin-plate spline provides the second best results of the methods selected and with the test data used.

  • 46. Pell, Mikael
    et al.
    Wörman, Anders
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik, Vattendragsteknik.
    Biological wastewater treatment systems2008Ingår i: Encyclopedia of ecology / [ed] Sven Erik Jorgensen; Brian D Fath, Amsterdam: Elsevier, 2008, s. 426-441Kapitel i bok, del av antologi (Refereegranskat)
  • 47. Ramanathan, A. L.
    et al.
    Tripathi, P.
    Ranjan, R.
    Kumar, M.
    Bhattacharya, Prosun
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630).
    Elfverson, Katarina
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630).
    Thunvik, Roger
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630).
    Jacks, Gunnar
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630).
    Sracek, O.
    Bundschuh, Jochen
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630). Karlsruhe University of Applied Sciences, Karlsruhe, Germany .
    Tsujimura, M.
    Hydrogeochemistry of the alluvial aquifers of the central Gangetic Plain in India: Constraints on source and mobility of arsenic2010Ingår i: Arsenic in Geosphere and Human Diseases, As 2010 - 3rd International Congress: Arsenic in the Environment, 2010, s. 23-25Konferensbidrag (Refereegranskat)
  • 48. Ramos, O.
    et al.
    Ormachea, M.
    Niura, M.
    García, M. E.
    Quintanilla, J.
    Bhattacharya, Prosun
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630).
    Thunvik, Roger
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630).
    Jacks, Gunnar
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik (flyttat 20130630).
    Sracek, O.
    Arsenic and other trace elements in groundwater and surface water of the Poopó Basin and drinking water quality in Bolivian Altiplano2010Ingår i: Arsenic in Geosphere and Human Diseases, As 2010 - 3rd International Congress: Arsenic in the Environment, 2010, s. 517-519Konferensbidrag (Refereegranskat)
  • 49.
    Rasul, Hedi
    et al.
    Koya University.
    Wu, Mousong
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Vatten- och miljöteknik.
    Hansson, Klas
    Olofsson, Bo
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Vatten- och miljöteknik.
    Two-dimensional model for heat and moisture dynamics in Nordic roads: Model set-up and sensitivity analysisIngår i: Cold Regions Science and Technology, ISSN 0165-232X, E-ISSN 1872-7441Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    Modeling moisture and heat changes in road layers is important for understanding road hydrology, but also for better construction and maintenance of roads. The modeling task is more complicated in cold regions, due to the water-ice phase change in wintertime. This paper presents a two-dimensional model based on a road section. The water and heat transport equations, including freezing/thawing and vapor flow, were implemented within the COMSOL Multiphysics tool. Parameters were optimized from modeling results based on measured soil moisture and temperature at a road test station near Stockholm. Impacts of phase change in the model were assessed. The results showed that model developed can accurately predict temperature changes, water and ice content in different road layers based on pressure head and temperature gradient. The model of water dynamics performs much better than predicting the average water content in the upper road layer. Parameters related to soil water retention curve are optimized and most parameters influence water and heat change in the same direction, except the thermal conductivity of soil. The optimized parameters based on moisture content and temperature data from the sensors in the road section can be used in this model for testing different road materials and geometries. The model provides a clear understanding of water and heat transfer in roads with ideal boundary and initial conditions. For a better understanding of road heat and moisture dynamics, more physical processes can be added to the model in future work by coupling snow melt and surface flow models.

  • 50.
    Riehm, Mats
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik, Biogeofysik.
    Blomqvist, Michael
    Gustavsson, Torbjörn
    Bogren, Jörgen
    Jansson, Per-Erik
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Mark- och vattenteknik, Biogeofysik.
    IMAGE PROCESSING AS A METHOD FOR DETERMINING ROAD SNOW ACCUMULATIONManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Snowfall often causes limitations for road transportation and large efforts are devoted to snow removal. Snow that falls on a road surface often melts due to the surface being warmer than the air under some circumstances. Melting of snow can also be induced by use of road salt. Consequently, snow measurements by precipitation sensors along roads may indicate thicker snow depths than are actually present on the roads. A method for determining the onset time of snow accumulation on roads based on a combination of precipitation measurements and image processing is presented. The method detects whether the snow accumulates rather than melts. It can be used to calculate accumulated snow depth, a more accurate measurement than using precipitation sensors alone. The method was tested over one winter and showed potential to improve the description of snow accumulation in a road network, which could lead to more efficient planning of snow removal.

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