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  • 101. Akoulitch, A
    et al.
    Höbeda, Peet
    Swedish National Road and Transport Research Institute.
    Influence of activation of filler on the properties of asphalt concrete1993Report (Other academic)
  • 102. Akoulitch, Alexandre
    et al.
    Busel, Alexej
    Photometric control of the milling fineness of mineral filler and cement1993Report (Other academic)
  • 103. Akoulitch, Alexandre
    et al.
    Busel, Alexej
    Technical perspective on the production of asphalt concrete modified by the addition of rubber at the asphalt plant1993Report (Other academic)
  • 104. Al-Agha, HR
    et al.
    Bacon, DGC
    A tensioned cable steering guidance system for crash testing of heavy goods vehicles1989Report (Other (popular science, discussion, etc.))
  • 105.
    Alatalo, Juha M
    et al.
    Uppsala Universitet, Campus Gotland.
    Jägerbrand, Annika K
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Molau, Ulf
    Göteborg Universitet.
    Climate change and climatic events: Community-, functional- and species-level responses of bryophytes and lichens to constant, stepwise, and pulse experimental warming in an alpine tundra2014In: Alpine Botany, ISSN 1664-2201, Vol. 124, no 2, p. 81-91Article in journal (Refereed)
    Abstract [en]

    We experimentally imposed three different kinds of warming scenarios over 3 years on an alpine meadow community to identify the differential effects of climate warming and extreme climatic events on the abundance and biomass of bryophytes and lichens. Treatments consisted of (a) a constant level of warming with open top chambers (an average temperature increase of 1.87 °C), (b) a yearly stepwise increase of warming (average temperature increases of 1.0; 1.87 and 3.54 °C, consecutively), and (c) a pulse warming, i.e., a single first year pulse event of warming (average temperature increase of 3.54 °C only during the first year). To our knowledge, this is the first climate change study that attempts to distinguish between the effects of constant, stepwise and pulse warming on bryophyte and lichen communities. We hypothesised that pulse warming would have a significant short-term effect compared to the other warming treatments, and that stepwise warming would have a significant mid-term effect compared to the other warming treatments. Acrocarpous bryophytes as a group increased in abundance and biomass to the short-term effect of pulse warming. We found no significant effects of mid-term (third-year) stepwise warming. However, one pleurocarpous bryophyte species, Tomentypnum nitens, generally increased in abundance during the warm year 1997 but decreased in control plots and in response to the stepwise warming treatment. Three years of experimental warming (all treatments as a group) did have a significant impact at the community level, yet changes in abundance did not translate into significant changes in the dominance hierarchies at the functional level (for acrocarpous bryophytes, pleurocarpous bryophytes, Sphagnum or lichens), or in significant changes in other bryophyte or lichen species. The results suggest that bryophytes and lichens, both at the functional group and species level, to a large extent are resistant to the different climate change warming simulations that were applied.

  • 106.
    Alatalo, Juha M
    et al.
    Qatar University.
    Jägerbrand, Annika K
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Molau, Ulf
    Göteborgs Universitet.
    Impacts of different climate change regimes and extreme climatic events on an alpine meadow community2016In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6, article id 21720Article in journal (Refereed)
    Abstract [en]

    Climate variability is expected to increase in future but there exist very few experimental studies that apply different warming regimes on plant communities over several years. We studied an alpine meadow community under three warming regimes over three years. Treatments consisted of (a) a constant level of warming with open-top chambers (ca. 1.9 °C above ambient), (b) yearly stepwise increases in warming (increases of ca. 1.0, 1.9 and 3.5 °C), and (c) pulse warming, a single first-year pulse event of warming (increase of ca. 3.5 °C). Pulse warming and stepwise warming was hypothesised to cause distinct first-year and third-year effects, respectively. We found support for both hypotheses; however, the responses varied among measurement levels (whole community, canopy, bottom layer, and plant functional groups), treatments, and time. Our study revealed complex responses of the alpine plant community to the different experimentally imposed climate warming regimes. Plant cover, height and biomass frequently responded distinctly to the constant level of warming, the stepwise increase in warming and the extreme pulse-warming event. Notably, we found that stepwise warming had an accumulating effect on biomass, the responses to the different warming regimes varied among functional groups, and the short-term perturbations had negative effect on species richness and diversity.

  • 107.
    Alatalo, Juha M.
    et al.
    Uppsala Universitet.
    Jägerbrand, Annika
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Molau, Ulf
    University of Gothenburg.
    Seven years of experimental warming and nutrient addition causes decline of bryophytes and lichens in alpine meadow and heath communitiesManuscript (preprint) (Other academic)
    Abstract [sv]

    Global change is predicted to have large and rapid impact on polar and alpine regions. Bryophytes and lichens increase their importance in terms of biomass, carbon/nutrient cycling, cover and ecosystem functioning at higher latitudes/altitudes. Here we report from a seven year factorial experiment with nutrient addition and warming on the abundance of bryophytes and lichens in an alpine meadow and heath community. Treatments had significant negative effect on relative change of total abundance bryophytes and lichens, the largest decline to the nutrient addition and the combined nutrient addition and warming treatments, bryophytes decreasing most in the meadow, lichens most in the heath. Nutrient addition, and the combined nutrient addition and warming brought rapid decrease in both bryophytes and lichens, while warming had a delayed negative impact. Of sixteen species that were included the statistical analyses, we found significant negative effects on seven species. We show that impact of simulated global change on bryophytes and lichens differ in in time and magnitude among treatments and plant communities. Our results underscore the importance of longer-term studies to improve the quality of climate change models, as short-term studies are poor predictors of longer-term responses of bryophytes and lichens, similar to what have been shown for vascular plants. Species-specific responses may differ in time, and this will likely cause changes in the dominance structures of bryophytes and lichens over time.

  • 108.
    Alatalo, Juha, M.
    et al.
    Uppsala Universitet.
    Jägerbrand, Annika
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Molau, Ulf
    Göteborgs Universitet.
    Testing reliability of short-term responses to predict longer-term responses of bryophytes and lichens to environmental change2015In: Ecological Indicators, ISSN 1470-160X, E-ISSN 1872-7034, Vol. 58, p. 77-85Article in journal (Refereed)
    Abstract [en]

    Environmental changes are predicted to have severe and rapid impacts on polar and alpine regions. At high latitudes/altitudes, cryptogams such as bryophytes and lichens are of great importance in terms of biomass, carbon/nutrient cycling, cover and ecosystem functioning. This seven-year factorial experiment examined the effects of fertilizing and experimental warming on bryophyte and lichen abundance in an alpine meadow and a heath community in subarctic Sweden. The aim was to determine whether short-term responses (five years) are good predictors of longer-term responses (seven years). Fertilizing and warming had significant negative effects on total and relative abundance of bryophytes and lichens, with the largest and most rapid decline caused by fertilizing and combined fertilizing and warming. Bryophytes decreased most in the alpine meadow community, which was bryophyte-dominated, and lichens decreased most in the heath community, which was lichen-dominated. This was surprising, as the most diverse group in each community was expected to be most resistant to perturbation. Warming alone had a delayed negative impact. Of the 16 species included in statistical analyses, seven were significantly negatively affected. Overall, the impacts of simulated warming on bryophytes and lichens as a whole and on individual species differed in time and magnitude between treatments and plant communities (meadow and heath). This will likely cause changes in the dominance structures over time. These results underscore the importance of longer-term studies to improve the quality of data used in climate change models, as models based on short-term data are poor predictors of long-term responses of bryophytes and lichens.

  • 109.
    Alatalo, Juha M
    et al.
    Qatar University.
    Jägerbrand, Annika
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Čuchta, Peter
    Academy of Science of the Czech Republic.
    Collembola at three alpine subarctic sites resistant to twenty years of experimental warming2015In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 5, article id 18161Article in journal (Refereed)
    Abstract [en]

    This study examined the effects of micro-scale, site and 19 and 21 years of experimental warming on Collembola in three contrasting alpine subarctic plant communities (poor heath, rich meadow, wet meadow). Unexpectedly, experimental long-term warming had no significant effect on species richness, effective number of species, total abundance or abundance of any Collembola species. There were micro-scale effects on species richness, total abundance, and abundance of 10 of 35 species identified. Site had significant effect on effective number of species, and abundance of six species, with abundance patterns differing between sites. Site and long-term warming gave non-significant trends in species richness.

    The highest species richness was observed in poor heath, but mean species richness tended to be highest in rich meadow and lowest in wet meadow. Warming showed a tendency for a negative impact on species richness. This long-term warming experiment across three contrasting sites revealed that Collembola is capable of high resistance to climate change. We demonstrated that micro-scale and site effects are the main controlling factors for Collembola abundance in high alpine subarctic environments. Thus local heterogeneity is likely important for soil fauna composition and may play a crucial role in buffering Collembola against future climate change.

  • 110.
    Alatalo, Juha M.
    et al.
    Department of Ecology and Genetics, Uppsala University, Visby, Sweden.
    Little, Chelsea, J.
    Department of Ecology and Genetics, Uppsala University, Visby, Sweden.
    Jägerbrand, Annika
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Molau, Ulf
    Göteborgs Universitet.
    Dominance hierarchies, diversity and species richness of vascular plants in an alpine meadow: contrasting short and medium term responses to simulated global change2014In: PeerJ, ISSN 2167-8359, E-ISSN 2167-8359, Vol. 2, article id e406Article in journal (Refereed)
    Abstract [en]

    We studied the impact of simulated global change on a high alpine meadow plant community. Specifically, we examined whether short-term (5 years) responses are good predictors for medium-term (7 years) changes in the system by applying a factorial warming and nutrient manipulation to 20 plots in Latnjajaure, subarctic Sweden. Seven years of experimental warming and nutrient enhancement caused dramatic shifts in dominance hierarchies in response to the nutrient and the combined warming and nutrient enhancement treatments. Dominance hierarchies in the meadow moved from a community being dominated by cushion plants, deciduous, and evergreen shrubs to a community being dominated by grasses, sedges, and forbs. Short-term responses were shown to be inconsistent in their ability to predict medium-term responses for most functional groups, however, grasses showed a consistent and very substantial increase in response to nutrient addition over the seven years.

    The non-linear responses over time point out the importance of longer-term studies with repeated measurements to be able to better predict future changes. Forecasted changes to temperature and nutrient availability have implications for trophic interactions, and may ultimately influence the access to and palatability of the forage for grazers. Depending on what anthropogenic change will be most pronounced in the future (increase in nutrient deposits, warming, or a combination of them both), different shifts in community dominance hierarchies may occur. Generally, this study supports the productivity–diversity relationship found across arctic habitats, with community diversity peaking in mid-productivity systems and degrading as nutrient availability increases further. This is likely due the increasing competition in plant–plant interactions and the shifting dominance structure with grasses taking over the experimental plots, suggesting that global change could have high costs to biodiversity in the Arctic.

  • 111.
    Alatalo, Juha, M.
    et al.
    Uppsala Universitet.
    Little, Chelsea, J.
    Uppsala Universitet.
    Jägerbrand, Annika
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Molau, Ulf
    Göteborgs Universitet.
    Vascular plant abundance and diversity in an alpine heath under observed and simulated global change2015In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 5, p. 1-11, article id 10197Article in journal (Refereed)
    Abstract [en]

    Global change is predicted to cause shifts in species distributions and biodiversity in arctic tundra. We applied factorial warming and nutrient manipulation to a nutrient and species poor alpine/arctic heath community for seven years. Vascular plant abundance in control plots increased by 31%. There were also notable changes in cover in the nutrient and combined nutrient and warming treatments, with deciduous and evergreen shrubs declining, grasses overgrowing these plots. Sedge abundance initially increased significantly with nutrient amendment and then declined, going below initial values in the combined nutrient and warming treatment. Nutrient addition resulted in a change in dominance hierarchy from deciduous shrubs to grasses. We found significant declines in vascular plant diversity and evenness in the warming treatment and a decline in diversity in the combined warming and nutrient addition treatment, while nutrient addition caused a decline in species richness. The results give some experimental support that species poor plant communities with low diversity may be more vulnerable to loss of species diversity than communities with higher initial diversity. The projected increase in nutrient deposition and warming may therefore have negative impacts on ecosystem processes, functioning and services due to loss of species diversity in an already impoverished environment.

  • 112. Al-Babtain, Ibrahim
    et al.
    Abbas, Adil M
    Maintenance and repair of highway concrete bridges: A case study1991Report (Other (popular science, discussion, etc.))
  • 113. Albertsson, Pontus
    et al.
    Björnstig, Ulf
    Falkmer, Torbjörn
    Swedish National Road and Transport Research Institute.
    Turbell, Thomas
    Swedish National Road and Transport Research Institute.
    Litteraturöversikt Skadehändelser relaterade till busstrafik: Buss-OLA - en trafiksäker bussfärd2003Report (Other academic)
    Abstract [en]

    The aim of this literature review was to describe the pattern of injuries and fatalities related to bus traffic. Furthermore, the aim was to identify possible future measurements for improvement of passive safety in buses. Bus crashes were presented in international literature virtually in as many ways as there were articles on the topic. Hence, the authors used the term bus incidents, in order to cover all types of injuries related to bus traffic. In this review only M2 and M3 buses, i.e. buses over 3.5 tonnes were included. In the vast majority of OECD countries, less than 1 % of the vehicle fleet was constituted of buses. Bus passenger's average person kilometres represented 10 % of the total road vehicle person kilometres annually.

    The number of fatalities and injured in bus incidents have been stable recent years in EU. The fatality risk is ten times lower for bus passengers compared with car occupants. Of all traffic fatalities, bus fatalities represented 0.3-0.5 %. The most frequent injury localisations from all types of bus crashes were lower limb (35 %), upper limb (33 %) and head/face (28 %). Rollovers occurred in almost all cases of severe crashes. Projection, total ejection, partial ejection, intrusion and smoke inhalation were the main injury mechanism. Three major injury groups in severe bus crashes were thoracic injuries, massive injuries and pelvic fractures.

    Heavy wind seemed to be capable of affecting the bus dynamics, particularly on highly built buses (e.g. as high as 4.3 meters). Unprotected road users were hit by buses in about 1/3 of all cases in Sweden. Side impact was most common for local buses (38 %). Boarding and alighting were contributing to injuries in about 1/3 of all cases. If the coach has more than one section it seems that the upper section is more exposed to risk for injuries than the lower section.

    Safety belts can improve the passive safety in buses. The 2-point belt prevents passenger ejection but in frontal crashes the jack knife effect could cause head and thoracic injuries. However, the 3- point belt provides the best restraint in rollovers and frontal crashes, as it keeps the passenger remained seated.

  • 114. Albertsson, Pontus
    et al.
    Linder, Astrid
    Swedish National Road and Transport Research Institute, Traffic and road users, Traffic safety, society and road-user.
    Evaluation of extrication techniques. - Is there any other quality measurement then time?2007Conference paper (Refereed)
  • 115.
    Albinsson, Anton
    et al.
    Chalmers Tekniska Högskola.
    Bruzelius, Fredrik
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle. Chalmers Tekniska Högskola.
    Hjort, Mattias
    Swedish National Road and Transport Research Institute, Traffic and road users, Driver and vehicle.
    Required friction utilization for friction estimation on wet asphalt, an experimental study2018In: The Dynamics of Vehicles on Roads and Tracks, CRC Press/Balkema , 2018, p. 407-412Conference paper (Refereed)
    Abstract [en]

    Real-time information about the friction coefficient between the tyre and the road can be used to improve active safety systems and is an enabler for autonomous vehicles. Large tyre force excitation is normally required to obtain an accurate friction estimate. This paper quantifies this requirement for four different tyre models on wet salted asphalt at water freezing temperatures. Cost functions and different tyre models are evaluated and the results are compared to a previous study performed for snow conditions. The suitability of commonly used tyre models for friction estimation on snow and wet asphalt has thus been investigated.

  • 116.
    Albinsson, Anton
    et al.
    Chalmers Tekniska Högskola.
    Bruzelius, Fredrik
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation. Chalmers Tekniska Högskola.
    Jacobson, Bengt
    Chalmers Tekniska Högskola.
    Jonasson, Mats
    Volvo Cars Cooperation.
    Tire Force Estimation Based on the Recursive Least Square Method Utilizing Wheel Torque Measurement2014Conference paper (Refereed)
    Abstract [en]

    This study investigates a new tire force estimator based on the recursive least square (RLS) method. Tire force estimation with known driving wheel torque is studied and compared to the case with torque estimation from the internal combustion engine. This is motivated by a future scenario with electric propulsion, which reasonably gives improved wheel torque estimations. Sensitivity to vehicle parameters and challenges with individual lateral tire force estimation are also investigated. The results, experimental and simulation data, show good performance and potential for tire force estimation using the RLS method.

  • 117.
    Albinsson, Anton
    et al.
    Chalmers Tekniska Högskola.
    Bruzelius, Fredrik
    Swedish National Road and Transport Research Institute, Traffic and road users, Vehicle technology and simulation. Chalmers Tekniska Högskola.
    Pettersson, Pierre
    BorgWarner TorqTransfer Systems,.
    Jonasson, Mats
    Kungliga Tekniska Högskolan.
    Jacobson, Bengt
    Chalmers Tekniska Högskola.
    Estimation of the inertial parameters of vehicles with electric propulsion2015In: Proceedings of the Institution of mechanical engineers. Part D, journal of automobile engineering, ISSN 0954-4070, E-ISSN 2041-2991, p. 1-18, article id 0954-4070Article in journal (Refereed)
    Abstract [en]

    More accurate information about the basic vehicle parameters can improve the dynamic control functions of a vehicle. Methods for online estimation of the mass, the rolling resistance, the aerodynamic drag coefficient, the yaw inertia and the longitudinal position of the centre of gravity of an electric hybrid vehicle is therefore proposed. The estimators use the standard vehicle sensor set and the estimate of the electric motor torque. No additional sensors are hence required and no assumptions are made regarding the tyre or the vehicle characteristics. Consequently, all information about the vehicle is available to the estimator.

    The estimators are evaluated using both simulations and experiments. Estimations of the mass, the rolling resistance and the aerodynamic drag coefficient are based on a recursive least-squares method with multiple forgetting factors. The mass estimate converged to within 3% of the measured vehicle mass for the test cases with sufficient excitation that were evaluated. Two methods to estimate the longitudinal position of the centre of gravity and the yaw inertia are also proposed. The first method is based on the equations of motion and was found to be sensitive to the measurement and parameter errors. The second method is based on the estimated mass and seat-belt indicators.

    This estimator is more robust and reduces the estimation error in comparison with that obtained by assuming static parameters. The results show that the proposed method improves the estimations of the inertial parameters. Hence, it enables online non-linear tyre force estimators and tyre-model-based tyre–road friction estimators to be used in production vehicles.

  • 118. Albus, C
    ITS: Safety-related driver assistance systems1998Report (Other (popular science, discussion, etc.))
  • 119. Albus, Cristoph
    Current state of motorcycle engineering and research on the active safety sector1992Report (Other (popular science, discussion, etc.))
  • 120.
    Aldman, B
    et al.
    Swedish National Road and Transport Research Institute.
    Thorngren, L
    Swedish National Road and Transport Research Institute.
    Larsson, S
    Swedish National Road and Transport Research Institute.
    Haveriundersökningar av vägtrafikolyckor i Uppsala län 1960-19711974Report (Other academic)
  • 121.
    Aldman, Bertil
    et al.
    Swedish National Road and Transport Research Institute.
    Turbell, Thomas
    Swedish National Road and Transport Research Institute.
    Huvudstöd1971Report (Other academic)
    Abstract [sv]

    I denna rapport anges frekvensen av och principerna för skydd mot skador på huvud och hals för förare och passagerare i bilar vid påkörning bakifrån. Resultaten av en undersökning över hur några av de vanligaste skyddssystem som f n finns i Sverige och Finland svarar mot dessa principer redovisas och diskuteras.

    Termen huvudstöd har, i analogi med utländskt språkbruk (eng headrests, ty Kopfstützen) , använts för sådana skyddssystem. Den i allmänt språkbruk vanliga benämningen nackstöd har undvikits då den i olika sammanhang bedömts vara mindre adekvat. Den alternativa benämningen nackskydd, som föreslagits i pressen, betecknar enligt svensk standard den del av klädseln på motoristhjälmar som täcker nacken och har därför bedömts som mindre lämplig för den typ av skyddssystem som här avses.

  • 122.
    Aldulaimi, Mustafa
    Concordia University, Montreal.
    Road lighting and safety: a pilot study of Arthabaska region2016Conference paper (Refereed)
    Abstract [en]

    We investigate the specification of roadway lighting for safety to understand the elements needed in statistical analysis of road collisions during night time. Several goals were targeted. First, which type of response is best, or whether both responses should be used. Second, which indicator of lighting should we favor? Third, which other factors should be included in the analysis and fourth, how effective is lighting in reducing nigh-time collision. The case study comprised illuminance and luminance measurements collected for the Arthabaska region in Quebec, along with available operational and geometric variables expected to explain roadway collisions. A zero-inflated negative-binomial model was used to analyze the impact of predictors on collision frequency and severity using classical maximum likelihood validated by a Full Bayesian regression. It was found that collision severity is best, resulting in more factors being significant in the expected sense of contribution. Luminance was the best indicator for road lighting. A correlation matrix aided in the identification of linearly dependencies between factors and the response or other factors. The last goal was investigated by comparing daytime with night-time collision analysis. The night time analysis included luminance and glare. The results were very close between day and night, with luminance proving to be an effective countermeasure for night collisions. A three-time difference on the coefficient for traffic volume was found. The use of a dummy variable related to standard levels of illumination is presented and will be key in future research for the estimation of effective levels of lighting.

  • 123. Alexandersson, Gunnar
    Upphandling av järnvägstrafik i konkurrens - omfattning och effekter 1989-981999Report (Other (popular science, discussion, etc.))
  • 124. Alexandersson, Gunnar
    et al.
    Hulten, Staffan
    Fölster, Stefan
    Hur effektiv är anbudskonkurrensen i Sverige?: erfarenheter från den lokala kollektivtrafikens avreglering1996Report (Other (popular science, discussion, etc.))
  • 125.
    Alexandersson, Gunnar
    et al.
    Stockholm school of economics.
    Hultén, Staffan
    Stockholm school of economics.
    Nilsson, Jan-Eric
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics Stockholm.
    Pyddoke, Roger
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics Stockholm.
    The liberalization of railway passenger transport in Sweden: outstanding regulatory challenges2012Report (Other academic)
    Abstract [en]

    The purpose of this paper is to describe Sweden’s recent reforms to open the railway passenger markets to entry, and to addresses four critical issues for the success of the reforms; the allocation of infrastructure capacity, the provision of maintenance and terminal facilities, the access to rolling stock and the provision of information and ticketing to travelers. The analysis shows that the legislation and regulatory tools that are needed to handle these challenges to a large extent remain to be developed.

  • 126.
    Alfredsson, Magnus
    et al.
    NCC.
    Karlsson, Robert
    Swedish National Road and Transport Research Institute, Infrastructure, Pavement Technology.
    Sjögren, Leif
    Swedish National Road and Transport Research Institute, Infrastructure, Infrastructure maintenance.
    Hintze, Staffan
    NCC.
    Johansson, Bo
    NCC.
    Lundström, Robert
    NCC.
    Winnerholt, Tomas
    Trafikverket.
    Funktionskriterier för vägkonstruktioner: Förstudie2010Report (Other academic)
    Abstract [sv]

    Det projekt som här rapporteras har som syfte att identifiera och beskriva de svårigheter och möjligheter som totalentreprenader medför, respektive erbjuder, för alla parter. Målet är att utveckla totalentreprenader på ett sådant sätt att branschens effektivitet ökas. Denna rapport är en förstudie där det studerats vilka krav som byggherren ska ställa på utföraren av en vägkonstruktion i en totalentreprenad med funktionsansvar och hur utföraren ska verifiera kraven. Arbetet har genomförts med medlemmar från olika aktörer i branschen och omfattat främst litteraturstudier och intervjuer. Kunskaper och erfarenheter har sammanställts och analyserats för att slutligen kondenseras ned till ett antal förslag till fortsatt arbete.

    Förstudien har pekat ut ett antal områden som viktiga för att påskynda framtida utveckling av totalentreprenader:

    Terminologi – idag råder viss begreppsförvirring

    Analys av funktionella krav i tidigare projekt

    Trafikantkrav

    Miljökrav

    Utveckling av funktionella krav i samverkan

    Väghållarekonomi

    Regelbetingade begränsningar av funktionella krav

    Uppföljning och underlättande av erfarenhetsackumulering

    Implementering av nya mått och mätmetoder

  • 127. Al-Ghamdi, Ali S
    An object-oriented knowledge-based expert system for correcting hazardous locations1996Report (Other (popular science, discussion, etc.))
  • 128.
    Ali, Arshad
    et al.
    East China Normal University.
    Molau, Ulf
    Göteborgs Universitet.
    Bai, Yang
    Chinese Academy of Sciences.
    Jägerbrand, Annika K
    Swedish National Road and Transport Research Institute, Society, environment and transport, Environment.
    Alatalo, Juha M.
    Qatar University.
    Diversity-productivity dependent resistance of an alpine plant community to different climate change scenarios2016In: Ecological research, ISSN 0912-3814, E-ISSN 1440-1703, Vol. 31, no 6, p. 935-945Article in journal (Refereed)
    Abstract [en]

    Here we report from a experiment imposing different warming scenarios [control with ambient temperature, constant level of moderate warming for 3 years, stepwise increase in warming for 3 years, and one season of high level warming (pulse) simulating an extreme summer event] on an alpine ecosystem to study the impact on species diversity–biomass relationship, and community resistance in terms of biomass production.

    Multiple linear mixed models indicate that experimental years had stronger influence on biomass than warming scenarios and species diversity. Species diversity and biomass had almost humpback relationships under different warming scenarios over different experimental years. There was generally a negative diversity–biomass relationship, implying that a positive diversity–biomass relationship was not the case.

    The application of different warming scenarios did not change this tendency. The change in community resistance to all warming scenarios was generally negatively correlated with increasing species diversity, the strength of the correlation varying both between treatments and between years within treatments. The strong effect of experimental years was consistent with the notion that niche complementarity effects increase over time, and hence, higher biomass productivity over experimental years. The strongest negative relationship was found in the first year of the pulse treatment, indicating that the community had weak resistance to an extreme event of one season of abnormally warm climate.

    Biomass production started recovering during the two subsequent years. Contrasting biomass-related resistance emerged in the different treatments, indicating that micro sites within the same plant community may differ in their resistance to different warming scenarios.

  • 129.
    Allard, Alexandra
    et al.
    Linköping Universitet.
    Takman, Johanna
    Swedish National Road and Transport Research Institute, Society, environment and transport, Transport economics.
    Uddin, Gazi Salah
    Linköping Universitet.
    Ahmed, Ali
    Linköping Universitet.
    The N-shaped environmental Kuznets curve: an empirical evaluation using a panel quantile regression approach2017In: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, p. 1-14Article in journal (Refereed)
    Abstract [en]

    We evaluate the N-shaped environmental Kuznets curve (EKC) using panel quantile regression analysis. We investigate the relationship between CO2 emissions and GDP per capita for 74 countries over the period of 1994–2012. We include additional explanatory variables, such as renewable energy consumption, technological development, trade, and institutional quality. We find evidence for the N-shaped EKC in all income groups, except for the upper-middle-income countries. Heterogeneous characteristics are, however, observed over the N-shaped EKC. Finally, we find a negative relationship between renewable energy consumption and CO2 emissions, which highlights the importance of promoting greener energy in order to combat global warming.

  • 130. Allen, Wade
    Crash avoidance models and driver/vehicle handling1988Report (Other (popular science, discussion, etc.))
  • 131. Allen, Wade R et al
    Validation of real-time man-in-the-loop simulation1991Report (Other (popular science, discussion, etc.))
  • 132.
    Allirani, Hemanthini
    et al.
    National Institute of Technology, Tiruchirappalli.
    Santhakumar, Moses
    National Institute of Technology, Tiruchirappalli.
    Kumar, Kavitha
    National Institute of Technology, Tiruchirappalli.
    Analysis of factors influencing traffic accidents: a case study of Tiruchirappalli city2018Conference paper (Refereed)
    Abstract [en]

     Road safety is a major concern in many developing countries including India. Road accidents are responsible for an increase in deaths and disability throughout the world. Road accidents lead to loss of life, property and affect the general welfare of the people and the economy. India accounts for 10% of global road accidents and has the highest death rate in the world. In India, traffic fatalities have increased by 4.6% from 2014 to 2015. The analysis of road accident data reveals that about 57 accidents and 17 deaths take place every hour on an average in Indian roads. Road accidents have been increasing alarmingly in Tamil Nadu, being a major state contributing to total no. of accidents in India. Tamil Nadu reported the highest number of road accidents in 2015 sharing about 13.8% of the total accidents in the country. Tamil Nadu accounts for about 10.7% and 15.9% of total road fatalities and injury accidents in the entire country. Tamil Nadu ranked second highest and first in the country for fatalities and minor injury accidents.

    A case study of Tiruchirappalli city is considered for the present study. Tiruchirappalli city is situated at the geographical center of Tamil Nadu. Every year, a number of people are killed or injured due to road accidents. In Tiruchirappalli between the year 2010 and 2015, about 924 fatal accidents were reported and 974 people were killed due to road accidents. Hence, it is essential to find solutions to mitigate the problem. Road accidents are influenced by many factors such as traffic flow, geometric design of road sections, horizontal curvature, vertical grade, lane width, and shoulder width etc. Predicting the exact cause for the road accident is complex. Studies were done relating the factors like traffic volume, speed, road characteristics, road geometrics etc., with the road accidents. This study focuses on analysing road accident data and the relationship between various factors influencing road accidents so that suitable accident remedial measures can be suggested to enhance road safety.

  • 133.
    Allström, Andreas
    et al.
    Linköpings universitet.
    Barceló, Jaume
    Universitat Politècnica de Catalunya.
    Ekström, Joakim
    Linköpings universitet.
    Grumert, Ellen
    Linköpings universitet.
    Gundlegård, David
    Linköpings universitet.
    Rydergren, Clas
    Linköpings universitet.
    Traffic management for smart cities2016In: Designing, developing, and facilitating smart cities: urban design to IoT solutions / [ed] Vangelis Angelakis, Elias Tragos, Henrich C. Pöhls, Adam Kapovits and Alessandro Bassi, Switzerland: Springer, 2016, p. 211-240Chapter in book (Other academic)
    Abstract [en]

    Smart cities, participatory sensing as well as location data available in communication systems and social networks generates a vast amount of heterogeneous mobility data that can be used for traffic management. This chapter gives an overview of the different data sources and their characteristics and describes a framework for utilizing the various sources efficiently in the context of traffic management. Furthermore, different types of traffic models and algorithms are related to both the different data sources as well as some key functionalities of active traffic management, for example short-term prediction and control.

  • 134.
    Allström, Andreas
    et al.
    Sweco.
    Kristoffersson, Ida
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. Kungliga Tekniska Högskolan.
    Susilo, Yusak
    KTH.
    Smartphone based travel diary collection: Experiences from a field trial in Stockholm2017In: Transportation Research Procedia, Elsevier B.V. , 2017, Vol. 26, p. 32-38Conference paper (Refereed)
    Abstract [en]

    Currently, there is a great need for new methods to collect travel data. Traditional methods have considerable drawbacks and, at the same time, the models used to analyse the transport system require more and more detailed and high-quality data. Since most smartphones are equipped with various sensors that can be used to determine the location of the smartphone, and since smartphones are integrated in the daily life of most people, they provide an unprecedented opportunity for large-scale travel data collection. This method has a great potential to solve the problems related to the estimation of distance/travel time, geographic coding of departure/destination locations and forgotten trips and it will also provide a more detailed and extensive data set.

    In a recently completed research project the feasibility of replacing or complementing the traditional travel diary, with a suite of tools that make use of smartphone collected travel data has been evaluated. The advantages and disadvantages of the traditional method and the proposed method were studied. For a fair comparison, both methods have been tested in the same city, at the same time, and with the same respondents. To achieve the objectives of the project, MEILI, a system that consists of a smartphone application for capturing the movement of users and a web application for allowing the users to annotate their movement, has been deployed. In total 2142 trips were collected and annotated by 171 users. 51 of the users annotated trips covering more than a week. The main findings of the paper are that smartphone based data collection is feasible, that the algorithms to save battery work well and that trips of the same respondent vary considerably depending on day of the week.

  • 135.
    Allström, Andreas
    et al.
    Trivector .
    Olstam, Johan
    Swedish National Road and Transport Research Institute, Society, environment and transport, Traffic analysis and logistics. Linköpings universitet, Kommunikations- och transportsystem.
    Thorsson, Tobias
    WSP .
    Analys av modeller för beräkning av framkomlighet i korsningar2008Report (Other academic)
  • 136. Alm, Charlotte
    et al.
    Lindberg, Erik
    Swedish National Road and Transport Research Institute.
    Betydelsen av upplevda risker och känslor av otrygghet vid resor med kollektivtrafik: en undersökning i Göteborg samt jämförelse med resultat från Norrköping och Stockholm2004Report (Other academic)
    Abstract [en]

    A questionnaire, including questions about perceived attractiveness, feelings of unsafety and different types of perceived risks connected to five different transport modes (car, city bus, tram, regional bus and commuter train), was filled out by 58 persons at the city library in Gothenburg. The results showed that perceived risk and worry of being bothered, threatened or attacked might have a larger impact on perceived attractiveness than perceived risk and worry of being seriously injured in traffic accidents. Similiar results were obtained in similar studies conducted in Norrköping and in Stockholm. Of the respondents in Gothenburg, 45 % stated that they avoid travelling with particularly tram during evenings and weekends, to the areas Angered or Bergsjön. The results obtained from the studies conducted in Gothenburg and in Stockholm also suggest that perceived risk and worry of being bothered, threatened or attacked affect feelings of unsafety. The results obtained from all three studies showed that certain circumstances, such as the bus stop etc. being situated next to a park, contribute to a high degree to feelings of unsafety while walking to, or waiting at, a bus stop etc. When travelling with a public transport mode feelings of unsafety arise for example when the driver/personnel do not supervise their vehicle. In all three studies, women stated to a higher extent than men that different circumstances contribute to feelings of unsafety.

  • 137.
    Alm, Charlotte
    et al.
    Linköpings universitet.
    Lindberg, Erik
    Banverket.
    Kollektivtrafik i storstad -: undviker människor att resa på grund av otrygghet?2003Report (Other (popular science, discussion, etc.))
    Abstract [en]

    A questionnaire, including questions pertaining to perceived attractiveness, feelings of unsafety and different types of risks connected to different transport modes (car, city bus, tram, regional bus, commuter train and subway), was filled out by 59 respondents. The results showed that perceived attractiveness might be affected by perceived risks and worry of being bothered, threatened or attacked by fellow passengers to a higher extent than perceived risks and worry of being involved in traffic accidents. Different circumstances, for instance the bus stop etc being remotely situated, were considered to contribute to feelings of unsafety when walking to and waiting at the bus stop etc. When travelling with different public transport modes the participants stated that they feel unsafe if for example drivers/personnel do not supervise their vehicle. Women stated to a higher extent than men that different circumstances contribute to feelings of unsafety when walking to and waiting at the bus stop etc. as well as when travelling with different public transport modes. A majority of the respondents stated that they avoid travelling with the red subway-line during night-time, especially during weekends. The respondents stated that they had a more positive attitude towards tram than towards regional bus and commuter train, which was not the case in a similar study conducted in Norrköping. This result might be explained by a successful introduction of a new tramway-line (Tvärbanan) in Stockholm.

  • 138. Alm, Charlotte
    et al.
    Lindberg, Erik
    Swedish National Road and Transport Research Institute.
    Upplevd trygghet vid resor med kollektiva transportmedel2002Report (Other academic)
    Abstract [en]

    The main objective was to study differences and similarities between different transport modes (car, city bus, tram, regional bus and commuter train) concerning perceived attractiveness, feelings of safety and different types of risks connected to the different transport modes. Another aim was to study to what extent different circumstances (for instance lighting) contribute to feelings of insecurity while travelling with different public transport modes. Finally, an objective was to study possible effects of individual differences (such as demographic variables). A questionnaire was constructed for these purposes and was filled out by 58 respondents. The results showed that people perceive feelings of safety and attractiveness to be different depending on the transport mode. People perceive private cars to be more attractive than public transport modes. Perceived attractiveness might be affected by perceived risks and worry of being bothered, threatened and violated by fellow passengers to a higher extent than perceived risks and worry of being involved in traffic accidents while travelling. Individual differences might have an affect on perceived attractiveness, feelings of safety and perceptions of risks.

  • 139.
    Alm, Håkan
    Swedish National Road and Transport Research Institute.
    Driver behaviour models and accident causation1989Report (Other academic)
  • 140.
    Alm, Håkan
    Swedish National Road and Transport Research Institute.
    Representation of large-scale environments1989Report (Other academic)
    Abstract [en]

    The purpose of this report is to, through a literature study, shed some light on peoples’ representation of large-scale environments. This knowledge will make it possible to adapt the information from a navigation or route guidance-system to the drivers representation of the environment. In other words, if one knows how drivers are thinking about their environment, then it is possible to provide them with information that they understand and can use effectively during navigation.

    Before considering the question of how people represent large-scale environments it seems necessary to briefly analyse the task of navigation. The reason is that the navigation task will, to some extent, determine what type of information a driver needs from the environment.

  • 141.
    Alm, Håkan
    et al.
    Swedish National Road and Transport Research Institute.
    Johansson, Roger
    Swedish National Road and Transport Research Institute.
    Trafik- och boendemiljö vid Turistvägen i Järvsö: En förmätning1988Report (Other academic)
  • 142.
    Alm, Håkan
    et al.
    Swedish National Road and Transport Research Institute.
    Nilsson, Lena
    Swedish National Road and Transport Research Institute.
    Changes in driver behaviour as a function of handsfree mobile phones: A simulator study1991Report (Other (popular science, discussion, etc.))
  • 143.
    Alm, Håkan
    et al.
    Swedish National Road and Transport Research Institute.
    Nilsson, Lena
    Swedish National Road and Transport Research Institute.
    Changes in driver behaviour as a function of handsfree mobile phones: A simulator study1994Report (Other academic)
  • 144.
    Alm, Håkan
    et al.
    Swedish National Road and Transport Research Institute.
    Nilsson, Lena
    Swedish National Road and Transport Research Institute.
    Changes in driver behaviour as a function of handsfree mobile telephones: A simulator study1991Report (Other academic)
  • 145.
    Alm, Håkan
    et al.
    Swedish National Road and Transport Research Institute.
    Nilsson, Lena
    Swedish National Road and Transport Research Institute.
    The effects of a mobile telephone task on driver behaviour in a car following situation1996Report (Other academic)
  • 146.
    Alm, Håkan
    et al.
    Swedish National Road and Transport Research Institute.
    Nilsson, Lena
    Swedish National Road and Transport Research Institute.
    Järmark, Stina
    Swedish National Road and Transport Research Institute.
    Savelid, John
    Hennings, Ulf
    The effects of landmark presentation on driver performance and uncertainty in a navigation task: A field study1992Report (Other academic)
  • 147.
    Alm, Irma
    Swedish National Road and Transport Research Institute.
    Transportabel komfort - komfortabel transport1989Report (Other academic)
  • 148.
    Alm, Irma
    et al.
    Swedish National Road and Transport Research Institute.
    Magnusson, Georg
    Swedish National Road and Transport Research Institute.
    Bilisters uppfattning om körkomfort och om det svenska vägnätet1992Report (Other academic)
  • 149.
    Alm, L-O
    Swedish National Road and Transport Research Institute.
    Mätning av vägbeläggningars makrotextur för friktionsbedömning: Principer och mätmetoder1979Report (Other academic)
  • 150.
    Alm, L-O
    Swedish National Road and Transport Research Institute.
    Spårbildning i vägbeläggningar. Olägenheter, kritiska spårdjup och mätmetoder1977Report (Other academic)
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