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  • 3201.
    Xiong, Zhitao
    et al.
    The University of New South Wales.
    Olstam, Johan
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Orchestration of driving simulator scenarios based on dynamic actor preparation and automated action planning2015In: Transportation Research Part C: Emerging Technologies, ISSN 0968-090X, E-ISSN 1879-2359, Vol. 56, p. 120-131Article in journal (Refereed)
    Abstract [en]

    In driving simulation, a scenario includes definitions of the road environment, the traffic situation, simulated vehicles’ interactions with the participant’s vehicle and measurements that need to be collected. The scenarios need to be designed in such a way that the research questions to be studied can be answered, which commonly imply exposing the participant for a couple of predefined specific situations that has to be both realistic and repeatable. This article presents an integrated algorithm based on Dynamic Actor Preparation and Automated Action Planning to control autonomous simulated vehicles in the simulation in order to generate predefined situations. This algorithm is thus able to plan driving actions for autonomous vehicles based on specific tasks with relevant contextual information as well as handling longitudinal transportation of simulated vehicles based on the contextual information in an automated manner. The conducted experiment shows that the algorithm is able to guarantee repeatability under autonomous traffic flow. The presented algorithm can benefit not only the driving simulation community, but also relevant areas, such as autonomous vehicle and in-vehicle device design by providing them with an algorithm for target pursue and driving task accomplishment, which can be used to design a human-vehicle cooperation system in the coming era of autonomous driving.

  • 3202.
    Xylia, Maria
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS. KTH, School of Industrial Engineering and Management (ITM), Centres, Integrated Transport Research Lab, ITRL.
    Leduc, S.
    Patrizio, P.
    Silveira, Semida
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Kraxner, F.
    Developing a dynamic optimization model for electric bus charging infrastructure2017In: Transportation Research Procedia, Elsevier, 2017, Vol. 27, p. 776-783Conference paper (Refereed)
    Abstract [en]

    Urban regions account for 64% of global primary energy use and 70% of carbon emissions. For that reason, options to decarbonize urban environments are receiving increasing attention. In this context, public transport shall play a key role in decarbonizing urban road transport. One efficient way to achieve that is shifting towards clean fuels and modern electric buses, an option that is already under implementation in several cities around the world. In this paper, the basis for developing a dynamic optimization model for establishing charging infrastructure for electric buses is presented, using Stockholm, Sweden, as a case study. The model places constraints depending on the bus stop type (end or middle stop) which affects the time available for charging at each particular location. It also identifies the optimal technology type for the buses: conductive or inductive. In addition, the electric buses compete with buses run on biogas or biodiesel. In this paper, we present the results of a cost minimization scenario with constraints placed on the available charging time and power, differentiated between end stops and major public transport hubs. The mean charging time is 7.33 minutes, with a standard deviation of 4.78 minutes for all bus stops. The inner city bus routes require less charging time, which ranges on average at around 3 minutes. The installation of chargers at the locations proposed in the model would require scheduling adjustments and careful planning for the density of charging occasions.

  • 3203.
    Xylia, Maria
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Leduc, Sylvain
    International Institute for Applied Systems Analysis (IIASA).
    Patrizio, Piera
    International Institute for Applied Systems Analysis (IIASA).
    Kraxner, Florian
    International Institute for Applied Systems Analysis (IIASA).
    Silveira, Semida
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    A future with electric buses? Placing bus chargers in Stockholm2016Conference paper (Other academic)
  • 3204.
    Xylia, Maria
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Leduc, Sylvain
    International Institute for Applied Systems Analysis (IIASA).
    Patrizio, Piera
    International Institute for Applied Systems Analysis (IIASA).
    Kraxner, Florian
    International Institute for Applied Systems Analysis (IIASA).
    Silveira, Semida
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Locating charging infrastructure for electric buses in Stockholm2017In: Transportation Research Part C: Emerging Technologies, ISSN 0968-090X, E-ISSN 1879-2359, Vol. 78, no 2017, p. 183-200Article in journal (Refereed)
    Abstract [en]

    Charging infrastructure requirements are being largely debated in the context of urban energy planning for transport electrification. As electric vehicles are gaining momentum, the issue of locating and securing the availability, efficiency and effectiveness of charging infrastructure becomes a complex question that needs to be addressed. This paper presents the structure and application of a model developed for optimizing the distribution of charging infrastructure for electric buses in the urban context, and tests the model for the bus network of Stockholm. The major public bus transport hubs connecting to the train and subway system show the highest concentration of locations chosen by the model for charging station installation. The costs estimated are within an expected range when comparing to the annual bus public transport costs in Stockholm. The model could be adapted for various urban contexts to promptly assist in the transition to fossil-free bus transport. The total costs for the operation of a partially electrified bus system in both optimization cases considered (cost and energy) differ only marginally from the costs for a 100% biodiesel system. This indicates that lower fuel costs for electric buses can balance the high investment costs incurred in building charging infrastructure, while achieving a reduction of up to 51% in emissions and up to 34% in energy use in the bus fleet.  

  • 3205.
    Xylia, Maria
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Silveira, Semida
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    The role of charging technologies in upscaling the use of electric buses in public transport: experiences from demonstration projectsIn: Transportation Research Part A: Policy and Practice, ISSN 0965-8564, E-ISSN 1879-2375Article in journal (Refereed)
    Abstract [en]

    Public transport is crucial for the functionality of urban systems. Electrification of public bus transport services is currently explored in various demonstration projects around the world. The aim of this paper is to discuss the main characteristics and differences between conductive and inductive charging technologies, and evaluate how charging infrastructure strategies could affect future upscaling of electric bus deployment in public transport. The focus is on the Nordic region. A survey with stakeholders involved with electric bus demonstration projects is performed for understanding the benefits and drawbacks of each solution, and identifying the main themes emerging from project implementation and upscaling. Advantages of the conductive charging include the maturity of the technology and its higher maximum charging power compared to currently available inductive alternatives. On the other hand, inductive technology entails other benefits, such as the lack of moving parts which could reduce the maintenance costs for infrastructure, as well as minimal visibility of the equipment. The main issues likely to impact the upscaling of electric bus use are related to the maturity, cost-effectiveness, compatibility, and charging efficiency of the available technologies.

  • 3206.
    Xylia, Maria
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Silveira, Semida
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    Georén, Peter
    KTH, School of Industrial Engineering and Management (ITM).
    Comparative analysis of charging technologies for electric buses: a meta-synthesis of international experiences2016Conference paper (Refereed)
    Abstract [en]

    Public transport is crucial for the functionality of urban systems. Globally, much attention is being given lately to reducing transport’s environmental impacts by shifting towards fossil-free fuels, while also improving service availability. In this context, electrification of bus transport is gaining popularity because of the high energy efficiency improvements that can be accrued, together with low emissions and noise reduction compared to conventional buses.

    Although several studies focus on engine performance and powertrain characteristics of electric buses for individual demonstration projects, there are few studies that analyze the role of bus charging technologies and charging strategies. Gathering and systematically analyzing existing experiences from electric bus demonstration projects around the world is necessary for understanding the benefits and drawbacks of emerging solutions. The aim of this paper is to fill this gap and offer a comparative analysis of various alternatives for electric bus charging. What are the characteristics of each technology and what are the main themes emerging when it comes to implementation? 

    The analysis draws from experiences around the world, which are systematically evaluated under guidelines of meta-synthesis, reviewing existing literature and complementing it with expert knowledge gathered from an electronic survey. The respondents belong to stakeholder groups involved with electric bus demonstration projects, such as public transport authorities, transport service operators, charging technology providers, municipalities, regional authorities, and academia. Particular attention is given to the Nordic region, where several successful initiatives are already in place.

    The preliminary results show a variety of choices among charging technologies, and it is not uncommon to have different strategies combined in the demonstration projects. The survey responses indicate that stakeholders participate in such projects primarily in order to gain knowledge about the technologies tested, as well as due to the potential environmental benefits from bus transport electrification. Common unexpected issues faced during project implementation include increased costs for infrastructure installation, difficulties in communication between the stakeholders involved, as well as unexpected technology compatibility issues.

    The decisive factors when choosing charging technologies are related to market-readiness, cost-effectiveness, replicability and operation costs of available technologies, but also the institutional set up that allow for the development of certain options over time. The analysis of the survey results links charging technologies and strategies to their advantages and disadvantages as acquired from experience, and explain the factors behind the choices made.

    The results are useful in helping to enrich the knowledge basis on transport electrification, shifting from individual empirical findings to a generalized framework for evaluation of technology choices when it comes to charging infrastructure. In this way, we extract knowledge that facilitates choosing the most appropriate charging technology, designing implementation strategies and avoiding pitfalls that have already been encountered elsewhere. 

  • 3207.
    Yang, Can
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geoinformatics. KTH, Royal Institute of Technology in Sweden.
    Gidofalvi, Gyözö
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geoinformatics.
    Fast map matching, an algorithm integrating hidden Markov model with precomputation2017In: International Journal of Geographical Information Science, ISSN 1365-8816, E-ISSN 1365-8824, p. 1-24Article in journal (Refereed)
    Abstract [en]

    Wide deployment of global positioning system (GPS) sensors has generated a large amount of data with numerous applications in transportation research. Due to the observation error, a map matching (MM) process is commonly performed to infer a path on a road network from a noisy GPS trajectory. The increasing data volume calls for the design of efficient and scalable MM algorithms. This article presents fast map matching (FMM), an algorithm integrating hidden Markov model with precomputation, and provides an open-source implementation. An upper bounded origin-destination table is precomputed to store all pairs of shortest paths within a certain length in the road network. As a benefit, repeated routing queries known as the bottleneck of MM are replaced with hash table search. Additionally, several degenerate cases and a problem of reverse movement are identified and addressed in FMM. Experiments on a large collection of real-world taxi trip trajectories demonstrate that FMM has achieved a considerable single-processor MM speed of 25,000–45,000 points/second varying with the output mode. Investigation on the running time of different steps in FMM reveals that after precomputation is employed, the new bottleneck is located in candidate search, and more specifically, the projection of a GPS point to the polyline of a road edge. Reverse movement in the result is also effectively reduced by applying a penalty.

  • 3208.
    Yang, Can
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geoinformatics.
    Gidofalvi, Gyözö
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geoinformatics.
    Mining and visual exploration of closed contiguous sequential patterns in trajectories2018In: International Journal of Geographical Information Science, ISSN 1365-8816, E-ISSN 1365-8824, Vol. 32, no 7, p. 1282-1303Article in journal (Refereed)
    Abstract [en]

    Large collections of trajectories provide rich insight into movement patterns of the tracked objects. By map matching trajectories to a road network as sequences of road edge IDs, contiguous sequential patterns can be extracted as a certain number of objects traversing a specific path, which provides valuable information in travel demand modeling and transportation planning. Mining and visualization of such patterns still face challenges in efficiency, scalability, and visual cluttering of patterns. To address these challenges, this article firstly proposes a Bidirectional Pruning based Closed Contiguous Sequential pattern Mining (BP-CCSM) algorithm. By employing tree structures to create partitions of input sequences and candidate patterns, closeness can be checked efficiently by comparing nodes in a tree. Secondly, a system called Sequential Pattern Explorer for Trajectories (SPET) is built for spatial and temporal exploration of the mined patterns. Two types of maps are designed where a conventional traffic map gives an overview of the movement patterns and a dynamic offset map presents detailed information according to user-specified filters. Extensive experiments are performed in this article. BP-CCSM is compared with three other state-of-the-art algorithms on two datasets: a small public dataset containing clickstreams from an e-commerce and a large global positioning system dataset with more than 600,000 taxi trip trajectories. The results show that BP-CCSM considerably outperforms three other algorithms in terms of running time and memory consumption. Besides, SPET provides an efficient and convenient way to inspect spatial and temporal variations in closed contiguous sequential patterns from a large number of trajectories.

  • 3209.
    Yang, Jiawei
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management, Industrial economics.
    Demand Forecast of China Courier Industry2016Independent thesis Advanced level (degree of Master (One Year)), 40 credits / 60 HE creditsStudent thesis
  • 3210.
    Yao, C.
    et al.
    Ludong University,Yantai, China.
    Gu, J. -C
    Ludong University,Yantai, China.
    Yang, Qi
    Traffic congestion identification and analysis of urban roadnetworkbased on granular computing2014In: Applied Mechanics and Materials, 641-642, 2014, 2014, p. 916-922Conference paper (Refereed)
    Abstract [en]

    This paper proposes a generalized model based on the granular computing to recognize and analyze the traffic congestion of urban road network. Using the method of quotient space to reduce the attributes associatingwith traffic congestion, the identification of traffic congestion evaluation system is established including 3 first class indexes and second class indexes of 11. The weight of evaluation indexes are sorted by value in descending order, which are calculated based on rough set theory. In order to improve the efficiency of traffic congestion identification, the appropriate granular is determined by the model parameter μ. When μis larger, the identification is more effective and the run time of model is longer conversely. Experiments show when the value of μ is between 0.8 and 0.98, the effect of traffic congestion identification is comprehensive optimal.

  • 3211.
    Ye, Zi
    University of Gävle, Faculty of Engineering and Sustainable Development.
    Supply chain risk management on natural disaster: A study of global supply chain influence by2011Tohoku earthquake2011Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
  • 3212.
    Yousuf, Jabran
    et al.
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Rezaie, Hamed
    Linnaeus University, Faculty of Technology, Department of Building Technology.
    Fukt i material under byggskedet2017Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta arbete tar upp fuktproblemen vid materialförvaring samt vid leverans. Fokus i arbetet ligger på trämaterial, dock har även andra byggnadmaterial tagits upp. Fuktmätningar och intervjuer på byggarbetsplatser har gjorts för att få en bild på hur byggnadsmaterialet hanteras på byggarbetsplatser. Arbetet visar att beställaren kan ha en stor påverkan på hur byggnadsmaterialet hanteras på byggarbetsplatserna.

  • 3213.
    Yurtkulu, Emine Zehra
    et al.
    Jönköping University, School of Engineering, JTH. Research area Industrial Production.
    Hilletofth, Per
    Jönköping University, School of Engineering, JTH. Research area Industrial Production. Jönköping University, School of Engineering, JTH, Industrial Engineering and Management.
    Hilmola, Olli-Pekka
    Lappeenranta University of Technology, Kouvola Research Unit, Kouvola, Finland.
    Extended service use and new product possibilities in Swedish trucking2014In: World Review of Intermodal Transportation Research (WRITR), ISSN 1749-4729, E-ISSN 1749-4737, Vol. 5, no 1, p. 80-98Article in journal (Refereed)
    Abstract [en]

    The purpose of this study is to examine how extended services from vehicle manufacturers can enhance value and reduce risk for transportation companies. The research shows that some transportation companies found extended services useful in order to enhance value and to decrease risks, while some of the companies mentioned advantages of not using extended services. Increased customer service and increased up time are some of the value factors. Decreased number of delays and decreased likelihood of breakdowns are some of the risk factors mentioned by the case companies. This study contributes the knowledge by examining the transporters' experiences of using extended services. The study also identifies feedback loop to develop further physical products based on case study and user service package experiences - one key component in the further development is to use simultaneously financial and overall service packages.

  • 3214.
    Yurtkulu, Emine Zehra
    et al.
    Jönköping University, School of Engineering, JTH, Industrial Engineering and Management. Jönköping University, School of Engineering, JTH. Research area Industrial Production.
    Hilletofth, Per
    Jönköping University, School of Engineering, JTH, Industrial Engineering and Management. Jönköping University, School of Engineering, JTH. Research area Industrial Production.
    Johansson, Glenn
    Jönköping University, School of Engineering, JTH, Industrial Engineering and Management. Jönköping University, School of Engineering, JTH. Research area Industrial Production.
    Foundation of the integration of supply chain decisions in new product development2014In: Proceedings of the 21th International Annual EurOMA Conference, International Annual EurOMA Conference, 2014Conference paper (Refereed)
    Abstract [en]

    The purpose of this study is to identify and classify supply chain decisions, which havecritical roles in new product development. Supply chain management completes themissing part of the new product development puzzle and provides a holistic view onvarious operational aspects such as on-time product launch, capacity utilization,inventory management, and accurate order processing. Findings of this study arepresented in a conceptual framework. Identified supply chain decisions are classified ina generic new product development model based on the main logistics drivers such assupply, manufacturing planning and control and transportation, to increase theunderstanding about role of different logistics drivers in different phases of new productdevelopment.

  • 3215.
    Zachau, Christoffer
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Säfström, Erik
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Electronic Chart Display Information System: En kvalitativ studie om användarnas upplevelser av ruttplanering i ECDIS2018Independent thesis Basic level (professional degree), 10 HE creditsStudent thesis
    Abstract [sv]

    I det här examensarbetet undersöks den upplevda arbetsbelastningen vid ruttplanering i ECDIS. Syftet med studien är att undersöka hur svenska däcksbefäl inom handelssjöfarten upplever arbetsbelastningen vid ruttplanering med ECDIS. Studien syftar vidare till att undersöka vilka moment under ruttplanering i ECDIS däcksbefäl uppfattar som mest belastande. Studien är avgränsad till svenska sjöbefäl med erfarenhet av ruttplanering ombord. Resultaten visar att informanterna upplever problem med hårdvaran som levereras med installationen av ECDIS, ibland så stora problem att de ombord byter ut den medföljande hårdvaran mot annan hårdvara. De upplever även att det inte finns optimal arbetsyta vid arbete i ECDIS samt att det saknas avsatt tid till ruttplanering.

  • 3216.
    Zanuy, Carrillo
    et al.
    TUB.
    Boysen, Hans
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Traffic and Logistics.
    Mašek, J
    UNIZA.
    Buda, M
    UNIZA.
    Janíček, F
    TVP.
    Karabin, J
    TVP.
    VEL Wagon: State of the art and concept drafting2011Report (Other academic)
    Abstract [en]

    The present deliverable presents a general overview of the European rail freight system in terms of:

    Demand:

    Where the general characteristics and trends on freight transportation market are analysed, obtaining among other conclusions that more transport of processed high-valued goods with low density and higher space requirement is happening in contrast to transport of bulk cargo and heavy goods.

    Supply

    Where the freight railway system and its performance are analysed, being intermodal transportation and unit trains the business segments with major interest. The current wagon fleet characteristics together with their performance are discussed to produce guidelines for VEL-Wagon concepts, among which the multipurpose applications. 

    Infrastructure

    General overview of railway infrastructure characteristics paying especial attention to loading gauges and axle loads.

    Finally it presents rough concept definitions of VEL-Wagon based on partners evaluation.

  • 3217. Zech, A.
    et al.
    Attinger, S.
    Cvetkovic, Vladimir
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Dagan, G.
    Dietrich, P.
    Fiori, A.
    Rubin, Y.
    Teutsch, G.
    Is unique scaling of aquifer macrodispersivity supported by field data?2015In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 51, no 9, p. 7662-7679Article in journal (Refereed)
    Abstract [en]

    Spreading of conservative solutes in groundwater due to aquifer heterogeneity is quantified by the macrodispersivity, which was found to be scale dependent. It increases with travel distance, stabilizing eventually at a constant value. However, the question of its asymptotic behavior at very large scale is still a matter of debate. It was surmised in the literature that macrodispersivity scales up following a unique scaling law. Attempts to define such a law were made by fitting a regression line in the log-log representation of an ensemble of macrodispersivities from multiple experiments. The functional relationships differ among the authors, based on the choice of data. Our study revisits the data basis, used for inferring unique scaling, through a detailed analysis of literature marcodispersivities. In addition, values were collected from the most recent tracer tests reported in the literature. We specified a system of criteria for reliability and reevaluated the reliability of the reported values. The final collection of reliable estimates of macrodispersivity does not support a unique scaling law relationship. On the contrary, our results indicate, that the field data can be explained as a collection of macrodispersivities of aquifers with varying degree of heterogeneity where each exhibits its own constant asymptotic value. Our investigation concludes that transport, and particularly the macrodispersivity, is formation-specific, and that modeling of transport cannot be relegated to a unique scaling law. Instead, transport requires characterization of aquifer properties, e.g., spatial distribution of hydraulic conductivity, and the use of adequate models.

  • 3218. Zhang, Chao
    et al.
    Osorio, Carolina
    Flötteröd, Gunnar
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Efficient calibration techniques for large-scale traffic simulators2017In: Transportation Research Part B: Methodological, ISSN 0191-2615, E-ISSN 1879-2367, Vol. 97, p. 214-239Article in journal (Refereed)
    Abstract [en]

    Road transportation simulators are increasingly used by transportation stakeholders around the world for the analysis of intricate transportation systems. Model calibration is a crucial prerequisite for transportation simulators to reliably reproduce and predict traffic conditions. This paper considers the calibration of transportation simulators. The methodology is suitable for a broad family of simulators. Its use is illustrated with stochastic and computationally costly simulators. The calibration problem is formulated as a simulation based optimization (SO) problem. We propose a metamodel approach. The analytical meta model combines information from the simulator with information from an analytical differentiable and tractable network model that relates the calibration parameters to the simulation-based objective function. The proposed algorithm is validated by considering synthetic experiments on a toy network. It is then used to address a calibration problem with real data for a large-scale network: the Berlin metropolitan network with over 24300 links and 11300 nodes. The performance of the proposed approach is compared to a traditional benchmark method. The proposed approach significantly improves the computational efficiency of the calibration algorithm with an average reduction in simulation runtime until convergence of more than 80%. The results illustrate the scalability of the approach and its suitability for the calibration of large-scale computationally inefficient network simulators. (C) 2016 Elsevier Ltd. All rights reserved.

  • 3219.
    Zhang, Li
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Kong, Yanjun
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Industrial Development, IT and Land Management.
    Outlining benefits and barriers for employing four types of information system in fourth-party logistics2014Independent thesis Advanced level (degree of Master (One Year)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    This paper examines the process of employing four kinds of information systems in fourth-party logistics. The paper mainly tries to answer research questions: what is fourth-party logistics and information systems; what are benefits and barriers for using four kinds of information systems (RFID, WMS, EDI, Electronic marketplace) with the help of fourth-party logistics; what are unique benefits and barriers for fourth-party logistics to employ the four kinds of information systems and how to overcome the difficulties. To answer the research question, qualitative case study approach was employed and two case companies were chosen. Information in literature review was collected from secondary data for example scientific paper. Information in findings was collected from interviews of people in charge of the project and internal reports.

     

    Definitions of fourth-party logistics and information system were reviewed in literature review. The differences between fourth-party logistics and third-party logistics were presented as well. In addition, categorization of various kinds of advanced information systems was also listed.

     

    Benefits and barriers organized from literature and case studies were gathered and compared in discussion. Two significant benefits were identified: opportunities to do businesses with leading companies and improved efficiency. Two main barriers are confusion of the concept of fourth-party logistics and terminology of information system and financial justification. There are different opinions between the two case companies, literature review and empirical data, and between different literature. The paper concluded that there are many benefits and barriers for employing the four kinds of information systems in fourth-party logistics, and the future development of it is promising.

  • 3220.
    Zhang, Wei
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Jenelius, Erik
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Ma, Xiaoliang
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Freight transport platoon coordination and departure time scheduling under travel time uncertainty2017In: Transportation Research Part E: Logistics and Transportation Review, ISSN 1366-5545, E-ISSN 1878-5794, Vol. 98, p. 1-23Article in journal (Refereed)
    Abstract [en]

    The paper formulates and analyzes a freight transport platoon coordination and departure time scheduling problem under travel time uncertainty. The expected cost minimization framework accounts for travel time cost, schedule miss penalties and fuel cost. It is shown that platooning is beneficial only when scheduled arrival times differ less than a certain threshold. Travel time uncertainty typically reduces the threshold schedule difference for platooning to be beneficial. Platooning in networks is less beneficial on converging routes than diverging routes, due to delay at the merging point. The model provides valuable insights regarding platooning benefits for freight transport planning.

  • 3221.
    Zhang, Wei
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Ma, Xiaoliang
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Jenelius, Erik
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Planning of heavy-duty vehicle platoon formulation: basic scheduling problem considering travel time variance2016Conference paper (Refereed)
  • 3222.
    Zhang, Wei
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Sundberg, Marcus
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Karlström, Anders
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Platoon coordination with time windows: An operational perspective2017In: 20th EURO Working Group on Transportation Meeting, EWGT 2017, 4-6 September 2017, Budapest, Hungary, Elsevier, 2017, Vol. 27, p. 357-364Conference paper (Refereed)
    Abstract [en]

    It has been reported that platooning has the potential of saving fuel and increasing traffic throughput. We formulate a platoon coordination problem with soft time windows as a mixed-integer linear programming problem and solve it with exact solutions. The objective function consists of operation costs, schedule miss penalties and fuel costs. In the numerical example, a Swedish highway network model is used and the computation result shows that, for 21 vehicles, the total cost can be reduced by 3.5% when the optimal preferred arrival times are chosen. A random disturbance is then added to the optimal time windows and the optimal result shows great sensitivity with respect to the disturbance. When the mean of the disturbance becomes larger than 10 minutes, more than half of the platooning benefits will be lost. The study also analyzes the change of different cost compositions as disturbance increases.

  • 3223.
    Zhang, Yingfeng
    et al.
    Key Laboratory of Contemporary Design and Integrated Manufacturing Technology, School of Mechanical Engineering, Northwestern Polytechnical University, Shaanxi, China.
    Liu, Sichao
    Key Laboratory of Contemporary Design and Integrated Manufacturing Technology, School of Mechanical Engineering, Northwestern Polytechnical University, Shaanxi, China.
    Liu, Yang
    Department of Production, University of Vaasa, Vaasa, Finland.
    Li, Rui
    Key Laboratory of Contemporary Design and Integrated Manufacturing Technology, School of Mechanical Engineering, Northwestern Polytechnical University, Shaanxi, China.
    Smart box-enabled product–service system for cloud logistics2016In: International Journal of Production Research, ISSN 0020-7543, E-ISSN 1366-588X, Vol. 54, no 22, p. 6693-6706Article in journal (Refereed)
    Abstract [en]

    Modern logistics takes significant progress and rapid developments with the prosperity of E-commerce, particularly in China. Typical challenges that logistics industry is facing now are composed by a lack of sharing, standard, cost-effective and environmental package and efficient optimisation method for logistics tasks distribution. As a result, it is difficult to implement green, sustainable logistics services. Three important technologies, Physical Internet (PI), product–service system (PSS) and cloud computing (CC), are adopted and developed to address the above issues. PI is extended to design a world-standard green recyclable smart box that is used to encapsulate goods. Smart box-enabled PSS is constructed to provide an innovative sustainable green logistics service, and high-quality packaging, as well as reduce logistics cost and environmental pollution. A real-time information-driven logistics tasks optimisation method is constructed by designing a cloud logistics platform based on CC. On this platform, a hierarchical tree-structure network for customer orders (COs) is built up to achieve the order-box matching of function. Then, a distance clustering analysis algorithm is presented to group and form the optimal clustering results for all COs, and a real-time information-driven optimisation method for logistics orders is proposed to minimise the unused volume of containers. Finally, a case study is simulated to demonstrate the efficiency and feasibility of proposed cloud logistics optimisation method. © 2016 Informa UK Limited, trading as Taylor & Francis Group.

  • 3224.
    Zhang, Yizhou
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Jenelius, Erik
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Kottenhoff, Karl
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport Planning, Economics and Engineering.
    Impact of real-time crowding information: A Stockholm metro case study2017In: Public Transport, ISSN 1866-749X, E-ISSN 1613-7159, Vol. 9, no 3, p. 483-499Article in journal (Refereed)
    Abstract [en]

    The paper evaluates the impact of real-time crowding information (RTCI) provision based on a pilot study at a Stockholm metro station. During a 6-day test period, RTCI for each car in the next arriving train was provided through a visual display and speakers. The impact is evaluated in three dimensions: (1) passenger attention is analyzed using video analysis; (2) passenger valuation is evaluated with traveler surveys; (3) passenger action is analyzed with in-vehicle passenger load data. It is estimated that around 25% of the passengers noticed, understood and considered the provided information useful for their travel decisions. Further, RTCI had a statistically significant positive impact on the boarding distribution between cars and, as a result, on the downstream in-vehicle crowding in the trains. RTCI reduced the share of passengers boarding the first, most crowded car by 4.3% points for trains that were crowded on arrival, and increased the share of passengers boarding the second, less crowded car by 4.1% points. The findings also suggest that many passengers may value the provided crowding information positively even though it does not change their travel decisions. The results indicate that RTCI may be a useful technology for public transport operators and agencies for increasing the utilization of available train capacity and reducing crowding.

  • 3225.
    Zhao, Xiaoyun
    et al.
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    Carling, Kenneth
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    Håkansson, Johan
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    An evaluation of the reliability of GPS-based transportation data2017In: Proceedings of IAC in Vienna 2017, 2017, p. 323-334, article id IAC201711035Conference paper (Refereed)
    Abstract [en]

    GPS-based data are becoming a cornerstone for real-time transportation applications. Tracking data of vehicles from GPS receivers are however susceptible to measurement errors. The assessment of the reliability of data from GPS receiver is a neglected issue, especially in a real road network setting and in the phase after data transfer but before information identification. An evaluation method is outlined and carried out by conducting a randomized experiment. We assess the reliability of GPS-based transportation data on geographical position, speed, and elevation from three varied receivers GlobalSat BT-338X, Magellan SporTrak Pro and smart phone for three transportation modes: bicycle, car, and bus. The positional error ranging from 0158 meters, and 74% to 100% with an error within 5 meters depending on the transportation mode and route, there is also a non-negligible risk for aberrant positioning. Speed is slightly underestimated or overestimated with errors around 5km/h except for SporTrak Pro which had an error of -10 km/h. Elevation measurements are unreliable with errors bigger than 100 meters.

  • 3226.
    Zhao, Yixin
    Linköping University, Department of Mathematics, Optimization . Linköping University, Faculty of Science & Engineering.
    On the Integration of Heuristics with Column-Oriented Models for Discrete Optimization2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Column-oriented models are today common in the eld of discrete optimization, and there is an increasing interest in using such models as a basis for heuristic solution methods. The common theme of this work is to explore some possibilities to integrate heuristic principles and column-oriented models for discrete optimization problems.

    In the rst paper, we consider a resource allocation problem for cellular systems. We propose a strong column-oriented formulation and a corresponding column generation method, as well as an enhanced column generation scheme for this problem. The enhanced scheme is composed of a stabilization technique, an approximate column generation principle, and, for nding integer solutions, a heuristic that is embedded in the column generation scheme.

    The second paper provides a new and strong convexied formulation of the xed charge transportation problem. This formulation is obtained by integrating the concepts of Lagrangian decomposition and column generation. It is shown both theoretically and practically that this integration yields a formulation which is stronger than three other convexied formulations of the problem.

  • 3227. Zhao, Yong
    et al.
    Kockelman, Kara
    Karlström, Anders
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, Transport and Location Analysis. KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Welfare calculations in discrete choice settings: an exploratory analysis of error term correlation with finite populations2012In: Transport Policy, ISSN 0967-070X, E-ISSN 1879-310X, Vol. 19, no 1, p. 76-84Article in journal (Refereed)
    Abstract [en]

    A difference in logsum terms (also known as inclusive values) is becoming a standard practice for anticipating the welfare impacts of transport policy when choice alternatives are discrete and behavior is (assumed to be) random-utility maximizing. However, this calculation is only an approximation when the population under study is finite. This paper examines the effect of error term correlations in such welfare analyses with finite samples, recognizing that individual preferences and unobserved attributes influencing choice are unlikely to change much, if at all, across scenarios or across alternatives. Such measures appear reasonably robust to deviations in assumptions of correlation. Nevertheless, we identify cases when the synthetic population samples need to be quite large for the average logsum to be realized. Another finding in these results is the substantial variation that emerges across synthetic populations, suggesting that policies that appear welfare-improving (when evaluated with average welfare formulations) may well be welfare-reducing (or vice versa) for a wide variety of actual, finite populations.

  • 3228. Zhao, Yong
    et al.
    Kockelman, Kara
    Karlström, Anders
    KTH, School of Architecture and the Built Environment (ABE), Transport and Economics (closed 20110301), Transport and Location Analysis (closed 20110301). KTH, School of Architecture and the Built Environment (ABE), Centres, Centre for Transport Studies, CTS.
    Welfare Calculations in Discrete-Choice Settings: The Role of Error Term Correlation2008In: Proceedings of the 87th Annual Meeting of the Transportation Research Board, 2008Conference paper (Refereed)
  • 3229.
    Ziedén, Therése
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Development of a Logit model of the transition effect to public transport2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The importance of traffic planning has, throughout the years, been in- creased, providing sustainable developments of traffic and infrastructural investments. The analysis of the current traffic situation and the evalua- tion of the effects of a future investment are crucial for the socio-economic benefits maintenance. These analyses and evaluations are most commonly done using traffic simulation models. One of the main traffic planning aims, nowadays, is to increase the number of public transport users against the number of private car users. This change in mode choice is called transition effect and could be beneficial both from an environmental and socio-economic perspective. This thesis aims to evaluate and improve the macroscopic traffic demand and transition model, used fot the city of Norrköping. Additionally, the thesis investigates if a general transition Logit model can be developed and which parameters are the most important to be included in a modal choice estimation. For the needs of this study, the traffic planning software Visum is used. The travel mode distribution is calculated by Logit models coded in Python-scripts integrated in Visum. Then, a traffic assignment is performed by Visum, computing new travel times as inputs to the Logit model and this iterative procedure continues until the system reaches an equilibrium. The thesis aims for a more reliable prediction of the transition effect by correcting the Python-scripts and estimating the parameters of the Logit model using data from surveys. The study shows that travel times is the most important factor for realistic results generation. However, the data used for the estimation of the Logit model parameters did not include sufficient information of travel times. The travel times had to be calculated, using two different methods, in order to be included in the estimation of new parameters. Although these methods could not provide any positive effects on the transition, they did prove the importance and significance travel time have when developing a traffic model. The result of the study invokes the importance to further develop the method of calculating travel times, when the input data is not sufficient, and shows that the travel time parameters are case specific.

  • 3230.
    Zimmermann, Maëlle
    et al.
    Department of Computer Science and Operations Research, Universit\'e de Montr\'eal, QC, Canada.
    Blom Västberg, Oskar
    KTH, School of Architecture and the Built Environment (ABE), Transport Science, System Analysis and Economics. Royal Institute of Technology.
    Frejinger, Emma
    Department of Computer Science and Operations Research, Universit\'e de Montr\'eal, QC, Canada.
    Karlström, Anders
    Capturing correlation with a mixed recursive logit model for activity-travel schedulingManuscript (preprint) (Other academic)
    Abstract [en]

    Representing activity-travel scheduling decisions as path choices in a time-space network is an emerging approach in the literature. In this paper, we model choices of activity, location, timing and transport mode using such an approach and seek to estimate utility parameters. Relaxing the independence from irrelevant alternatives (IIA) assumption of the logit model in this setting raises a number of challenges. First, overlap in the network may not fully characterize the correlation between paths, due to their interpretation as activity schedules. Second, the large number of states that are needed to represent all possible locations, times and activity combinations imposes major computational challenges to estimate the model. We combine recent methodological developments to extend previous work that allow to model complex and realistic correlation patterns in this type of network. The resulting model is a mixed recursive logit which keeps the advantages of the recursive logit for prediction. We use sampled choices sets in order to estimate the model in reasonable time for large-scale, dense time-space networks. In addition to estimation results, we present an extensive empirical analysis which highlights the different substitution patterns when the IIA property is relaxed, and a cross-validation study which confirms improved out-of-sample fit.

  • 3231.
    Zisimopoulos, Dimitrios
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    En elektrifiering av den interna busstrafiken på Stockholm Arlanda Airport2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Functional and cost effective systems for the full electrification of a bus network are areas of intense research and development. The electrification can be accomplished using different technological solutions, for example using opportunity charging or using an electric road system – ERS. Both opportunity charging and ERS have the potential to be integrated into already existing bus lines. With opportunity charging, the regular dwell time at the end stops is used for the bus to recharge its batteries and with an ERS the bus can charge dynamically along the road. The purpose of this report is to analyze how the existing Alfa- and Beta line at Stockholm Arlanda Airport, in a functional and cost effective way, can be electrified using either opportunity charging or an ERS. The tradeoff between required charging power, battery capacity and the necessity to change the existing running schedule is explained in detail. In addition, the impact on the electrical grid is analyzed based on different load profiles of different charging stations using different power levels. The analysis is based on real data from the Alfa – and Beta line with its existing buses, the electrical grid at Arlanda and data provided by both the leading (electrical) bus manufacturers and the leading charging infrastructure manufacturers.  The outcome of this report suggests that a full electrification of the existing Alfa- and Beta line has the potential to lower CO2-emissions and energy use at a functional and cost effective way.

  • 3232.
    Zohrevandi, Elmira
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Effects of Complexity Factors on Controllers Workload in Stockholm Terminal Area2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Through a history of more than 50 years, the results of mathematical models have shown that controller workload is being driven by the complexity involved in the airspace environment. Part of this complexity is prompted by the dynamical behavior of traffic patterns. From the results of models describing controller’s workload, it is observed that predictability decreases the complexity. Therefore, the general idea behind this topic is to analyze how a specific notion of predictability influences the controller’s workload. This specific notion in this research is a type of automation that aircraft benefit from. In a more specific sense, the goal of this research was to analyze how the controllers handle the air traffic in different complex situations when exposed to different automation levels. The following dilemmas are focused through this work: - Information visualization of controllers’ interaction with radar screen - Quantification of dynamics of air traffic patterns - Modeling and quantification of controllers’ workload First, in order to have a grasp of the controllers’ interaction with the air traffic patterns, the controllers’ activities on the radar screen have been visualized in chapter 2. The visualization results for different automated conditions have been analyzed. Based on such analysis the criteria for problem space has been addressed and the main research question is identified. Next in chapter 3, the airspace complexity caused by air traffic flow has been studied and a set of known complexity factors are quantified using a novel calculation approach. With a logistics perspective toward airspace complexity, to calculate each complexity factor, a mathematical formulation has been used and the effects of each corresponding factor on controllers’ workload are addressed. Then in chapter 4, a novel approach toward modeling controller’s workload is presented. After implementing the model on 18 different scenarios, a model for controller’s workload has been developed in which around 60 percent of the en-route air traffic complexity values and around 80 percent of terminal air traffic complexity values could be well-matched with the workload values. From statistical point of view, the results are very much acceptable for experiments in which human factors are involved. Cognitive load has not been considered in the workload model which is the focus of a future work. Later on in chapter 5, the results for each complexity factor as well as workload models are analyzed and discussed for each sector separately. Based on the airspace complexity results, areas where traffic situation had become complex were identified and the controller’s response to different situations are discussed. For each complexity factor as well as workload, the results for three different scenarios featuring different automation levels for two en-route and terminal sectors are compared. At last in chapter 6, the main ideas are discussed, thesis conclusions are presented and possible future work is suggested.

  • 3233.
    Zomer, Lara-Britt
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Daamen, Winnie
    TU Delft.
    Meijer, Sebastiaan
    KTH, School of Technology and Health (STH), Health Systems Engineering, Health Care Logistics.
    Hoogendoorn, Serge
    TU Delft.
    Managing Crowds: The Possibilities and Limitations of Crowd Information During Urban Mass Events2015Conference paper (Refereed)
    Abstract [en]

    Thischapter,basedonamixedmethodresearchapproach,offersinsights into possibilities and limitations of using ICT measures for crowd management and distribution during urban mass events (UMEs). Based on literature, practical applications and analyses of research results, we propose crowd management should consider characteristics of both crowds and UMEs to increase information effectiveness. In relation to urban planning, results show that possibilities to influence a crowd’s behavior depend on available (and known) choice sets offered in various locations, while distances towards locations across city centers appear less important. Limitations appear to be related to scarce knowledge on what drives crowd members to adapt or adhere to their activity choice behavior. Such insights are essential for smart cities striving for an optimal use of infrastructural capacity, as both the ambiguous effects of ICT measures, as well as a crowd’s self-organizing capacity should be taken into account for delaying, solving and preventing dis- ruptions of pedestrian flows in city centers. 

  • 3234. Zomer, Lara-Britt
    et al.
    Moustaid, Elhabib
    KTH, School of Technology and Health (STH), Health Systems Engineering, Health Care Logistics.
    Meijer, Sebastiaan
    KTH, School of Technology and Health (STH), Health Systems Engineering, Health Care Logistics.
    A Meta-Model for Including Social Behavior and Data into Simulation in the Smart City Context2015In: Proceedings of the 2015 Winter Simulation Conference / [ed] L. Yilmaz, W. K. V. Chan, I. Moon, T. M. K. Roeder, C. Macal, and M. D. Rossetti, 2015Conference paper (Refereed)
    Abstract [en]

    mart city management can be regarded to bridge different realms of thinking about cities, i.e., 1) the city as complex-adaptive system, 2) socio-technical operational control center and 3) multi-actor policy-making. Underpinned by different world views and theoretical bodies, integration of the three realms puts forward new demands on simulation approaches and challenges current knowledge and available technology regarding integration of sub-models across different systems. In order to support urban transportation management, a holistic approach is needed that semantically connects the three realms by incorporation of human behavior and knowledge. Combining research on knowledge management and computer science, this paper presents a novel meta-framework as socio-technical hybrid simulation language to generalize integration of simulations, gaming and data for modeling urban transportation.

  • 3235.
    Zou, Liangchao
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Jing, Lanru
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Cvetkovic, Vladimir
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering.
    Modeling of Solute Transport in a 3D Rough-Walled Fracture-Matrix System2017In: Transport in Porous Media, ISSN 0169-3913, E-ISSN 1573-1634, Vol. 116, no 3, p. 1005-1029Article in journal (Refereed)
    Abstract [en]

    Fluid flow and solute transport in a 3D rough-walled fracture-matrix system were simulated by directly solving the Navier-Stokes equations for fracture flow and solving the transport equation for the whole domain of fracture and matrix with considering matrix diffusion. The rough-walled fracture-matrix model was built from laser-scanned surface tomography of a real rock sample, by considering realistic features of surfaces roughness and asperity contacts. The numerical modeling results were compared with both analytical solutions based on simplified fracture surface geometry and numerical results by particle tracking based on the Reynolds equation. The aim is to investigate impacts of surface roughness on solute transport in natural fracture-matrix systems and to quantify the uncertainties in application of simplified models. The results show that fracture surface roughness significantly increases heterogeneity of velocity field in the rough-walled fractures, which consequently cause complex transport behavior, especially the dispersive distributions of solute concentration in the fracture and complex concentration profiles in the matrix. Such complex transport behaviors caused by surface roughness are important sources of uncertainty that needs to be considered for modeling of solute transport processes in fractured rocks. The presented direct numerical simulations of fluid flow and solute transport serve as efficient numerical experiments that provide reliable results for the analysis of effective transmissivity as well as effective dispersion coefficient in rough-walled fracture-matrix systems. Such analysis is helpful in model verifications, uncertainty quantifications and design of laboratorial experiments.

  • 3236.
    Åhman, K-I
    Swedish National Road and Transport Research Institute.
    Omkörningar av lastbilar: Trafikstudier1972Report (Other academic)
  • 3237.
    Åkerman, Jonas
    et al.
    KTH .
    Gudmundsson, Henrik
    Technical University of Denmark.
    Hedegaard Sørensen, Claus
    Technical University of Denmark.
    Isaksson, Karolina
    Swedish National Road and Transport Research Institute, Society, environment and transport, Mobility, actors and planning processes.
    Olsen, Silvia
    Institute of Transport Economics.
    Kessler, Florian
    AustriaTech.
    Macmillan, James
    University of Oxford.
    How to manage barriers to formation and implementation of policy packages in transport2011Report (Other academic)
    Abstract [en]

    The aim of this study has been to explore success factors and barriers to the formation and implementation of single policy measures and policy packages in transport, and to identify strategies to manage such barriers. As a first step, we developed a typology of barriers and success factors for policy formation and implementation. Secondly, we carried out an empirical analysis of barriers and success factors in four cases of policy packaging: Urban Congestion Charging; National Heavy Vehicle Fees; Aviation in the European Emissions Trading System and The EU’s First Railway Package. The third and final task was to identify more general strategies to manage barriers in policy formation and implementation. A main conclusion in this report is that a conscious application of these strategies may contribute significantly to successful formation and implementation of even controversial policies or policy packages.

  • 3238.
    Åkesson, Christopher
    et al.
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Starborg, Rasmus
    Linnaeus University, Faculty of Technology, Kalmar Maritime Academy.
    Eskortbogsering: ökad säkerhet eller bara bekymmer?2016Independent thesis Basic level (degree of Bachelor), 10 HE creditsStudent thesis
    Abstract [en]

    This paper deals with escort towing and the pilots’ attitudes towards the usage of this. The method used is qualitative and the approach is hypothetico-deductive.  Results from the interviews conducted with pilots in Gothenburg harbor gave an impression that, in general, the pilots favored the use of escort towing although their opinions sometimes differed on what type of ships should be included and excluded by escort regulations. To further the study, a comparison has been made to an earlier American report on the Puget Sound area by using it as a basis for the Port of Gothenburg and the West Coast. The conclusion is that the pilots' attitudes towards escort towing will surely be the same given that the shipping industry is growing as well as transportation worldwide is increasing. With this in mind, it can be assumed that the requirements of safety will increase. In this case, it is believed that more ports may take after Gothenburg in terms of requirements and rules regarding escort towing.

  • 3239.
    Åsa, Weinholt
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Exploring Collaboration Between the Fire and Rescue Service and New Actors: Cost-efficiency and Adaptation2015Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The emergency services serves an important purpose in society by ensuring that people in need, regardless of their geographical location, receives help when they fall victims to undesirable incidents. Existing resources are however often limited and concentrated to urban areas making travel distances to remote areas long. Local authorities are also facing budget constraints and clients are becoming more demanding. This means that the emergency services need to do more, but with less resources. Collaboration with new actors has therefore been proposed as a solution. There exist several actors with basic knowledge in both fire suppression or medical treatment that might be able to contribute at an early stage in order to reduce response time and provide help to citizens in need. However, little research has been dedicated to investigating the possibilities and the potential of new collaborative practices in every day accidents.

    In this thesis collaboration between new actors and the fire and rescue service (FRS) in Sweden is studied. The aim is to analyze whether collaborative practices leads to an increased cost-efficiency, for the FRS and society as a whole. The thesis also aims to analyze how traditional actors and new actors adapt to collaborative practices.

    For evaluating cost-efficiency in the FRS stochastic frontier analysis is used and for analyzing the societal effects cost-benefit analysis is applied. In total three cases are studied; (1) security officers assisting the FRS in fire alarms (2) home care nurses collaborating with the FRS in medical alarms and (3) citizens responding to FRS-alarms through SMS.

    The results do not show that collaboration have led to increased cost-efficiency in the FRS during the studied time period. However, despite that no evidence for increased cost-efficiency is found in the FRS, there are several societal gains from collaborating related to e.g. equity, quality and effectiveness. And the costs for implementing collaborative arrangements are relatively low. It is however argued that to be able to get the most out of collaboration more emphasis should be put on building common platforms, where the different organizations and actors can communicate, share experiences, organize joint training sessions and actually collaborate. Today interaction outside the rescue site hardly exist between the collaborative partners; the actual collaboration between the FRS and the new actors is limited only to the response phase. Also, the FRS do not adapt their bureaucratic structures to collaborate with the new actors. Instead the changes associated with collaboration affect mainly the new actors, as an addition to their regular duties. Factors related to discretion, professional identity and personal motivation are identified as important for understanding how new actors adapt to collaboration.

  • 3240.
    Åsenholm, Andreas
    et al.
    Linnaeus University, Faculty of Science and Engineering, Kalmar Maritime Academy.
    Hult, Carl
    Linnaeus University, Faculty of Science and Engineering, Kalmar Maritime Academy.
    Insamling och hantering av data om sjömäns förhållande till arbete och yrke2012In: Sjömän och sjömansyrke 2010: en studie i attityder till arbete och yrke under olika skeden i sjömanslivet / [ed] Hult, Carl, Sjöfartshögskolan, Linnéuniversitetet , 2012, 1, p. 51-72Chapter in book (Other academic)
  • 3241.
    Åström, Elias
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Wahllöf, Magnus
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences.
    Konceptuell utformning av verkstadslayout: En fallstudie vid Saab AB2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A well-planned workshop is an important component for achieving effective productions.Many of the wastes within Lean, which most of the manufacturing companies want tominimize, can be neglected by a well-planned workshop layout. This creates a bigincentive for companies to plan workshops carefully prior to implementation orrebuilding.

    This study is a case study conducted at Saab in Linköping, which providing world-leadingproducts, services and solutions to the defence industry, civil security and aviation. Thestudy is conducted on a production section that produces cell layers for the fighter aircraftGripen. Saab is currently developing a new model of Gripen, Gripen E, which will soonstart to be batch produced. In order for Saab to be competitive in the future, the productionsection that produces cell layers needs to be rebuilt and adapted to the production ofGripen E.

    The purpose of the study is to investigate how a conceptual workshop layout for theproduction of cell layers can be designed with production flow and material transport inconsideration. Data collection in the study has consisted of qualitative data obtained frominterviews and observations with Saab employees and literature. Furthermore, data hasalso been obtained quantitatively where it was retrieved from article registers andestimated dimensions of machines and tools included in the production section. The studyis intended as a decision basis for Saab in the establishment of the new workshop.

    With support from theories from Lean and the subjective method of simplified systematiclayout planning, proposals for conceptual workshop layouts and finally a definitiveconceptual model have been developed. Furthermore, verification of the layout proposalsestablished by simplified systematic layout planning has been performed through amathematical programming where the goal has been to minimize the flow of processeswith respect to the flow. The results of the verification and the layout proposals that weremade showed similar results, indicating that the layout proposals made by the simplifiedsystematic layout planning can be compared. Following verification, decisions were madeon a final conceptual layout that was selected after a valuation process.

  • 3242.
    Öberg, Christina
    et al.
    Lunds Tekniska Högskola.
    Huge-Brodin, Maria
    Linköping University, Department of Management and Engineering, Logistics Management. Linköping University, The Institute of Technology.
    Björklund, Maria
    Linköping University, Department of Management and Engineering, Logistics Management. Linköping University, The Institute of Technology.
    Applying a network level in environmental impact assessments2012In: Journal of Business Research, ISSN 0148-2963, E-ISSN 1873-7978, Vol. 65, no 2, p. 247-255Article in journal (Refereed)
    Abstract [en]

    Researchers and society devote increasing interest to environmental impact assessments. The study here discusses and questions current assessment models by relating them to inter-organizational network analyses, and demonstrates that single entities as the basis for environmental impact assessments may not be in the best interests of society. Three case studies focusing on logistical solutions illustrate environmental effects on a single-entity and a network level. The paper concludes that considering environmental impacts on a single-entity level disregards indirect effects, which in turn has consequences for the environment. The paper points to the importance of identifying the appropriate level for analysis of environmental impacts since the single entity as the basis for assessments may undermine environmentally friendly intentions.

  • 3243.
    Öberg, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Johansson, Charlotta ()
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    By Maria Öberg, Senior research engineer/PhD-student, Kristina L. Nilsson, Professor, and Charlotta Johansson, Assistant Professor Luleå University of Technology2013Other (Other (popular science, discussion, etc.))
  • 3244.
    Öberg, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Governance for sustainable development of major European transport corridors: The Scandinavian-Mediterranean TEN-T core network corridor2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Intermodal road, rail, air and sea transport networks across the European Union (EU) calledTrans-European Networks for Transport (TEN-T) are currently being implemented. Keyelements, which should be implemented by 2030, are the most strategic TEN-T Core networkcorridors. These nine corridors are expected to enhance smoothness and sustainability oftransport across the EU, thereby enhancing cohesion between EU nations, and relate to non-EU nations. In the EU Regulation 1315/2013 a governance framework for implementation ofthe Core network corridors is outlined, which mainly involves appointment of a Europeancoordinator for each corridor, establishment of Corridor forums for consultations, andformulation of work plans and follow-up measures.This framework is now being implemented in practice. A recognised challenge in the processis engaging the numerous, diverse stakeholders. A possible solution is to introduceappropriate elements of complementary governance. Thus, in this doctoral research, suitablecomplementary governance to support the sustainable development of a Core networkcorridor was investigated. Complementary governance, a concept that was developed andrefined during the project, refers here to additional governance in relation to the governanceframework described for the EU Core network corridors in the EU Regulation 1315/2013.To address an identified gap in knowledge on the nature and utility of complementarygovernance a series of studies was carried out. The studies included a study of relevantacademic literature, studies of EU transport policy and implementation documents regardinggovernance and sustainability, a survey of views of Scandinavian-Mediterranean Corridorforum participants, and interviews with stakeholders in the Baltic Sea region. These studiescollectively constitute a case study, focusing on the Scandinavian-Mediterranean Corenetwork corridor, of the need for, and if a need is present the optimal design of,complementary governance in the process of sustainable development of a Core networkcorridor.The main findings of the studies are that the implementation process of the Core networkcorridors could benefit from complementary governance measures, mainly to increaseinclusiveness, which is crucial for a sustainable development. Complementary governancecould both deepen and broaden stakeholder awareness and involvement. This may haveseveral advantages, such as increasing possibilities for stakeholders to influence the processand benefit from the corridor, align activities, and promote cooperation and learning betweenstakeholders. Moreover, including stakeholders who are based outside the corridors mayimprove distributive aspects of the investments and reduce risks of focusing attention tooclosely on the corridors per se. However, broadening stakeholder inclusion also hasdisadvantages, as it increases the complexity of the process, which may impair itseffectiveness, and may lead to unrepresentative involvement due to differences instakeholders’ interests, administrative capacities and power. It also increases requirements forcoordination.The nature of complementary governance is multifaceted and related to diverse dimensions ofgovernance, such as processes, stakeholder participation and implementation documents. For complementary governance measures a flexible and task-specific multi-level design isemphasised, which may involve various types of engagement mechanisms. Further, thefindings showed a need to extend previously recognised types of public engagementmechanisms based on communication, consultation and participation in the decision-makingstage, by recognising another category, named stakeholder exchange. This category ischaracterised by stakeholder cooperation and collaboration in an implementation stage wheremain goals and policies already are in place.Areas for complementary governance in the implementation process of the Core networkcorridors were indicated in the interview study. They consisted of extended involvement ofprivate stakeholders, extended involvement of regional and local stakeholders, extendedinvolvement of stakeholders geographically external to the immediate corridor, and extendedinformation both generally and specifically (i.e. directed information to specific stakeholders).Several complementary governance measures that could potentially improve implementationof the Core network corridors were raised in the interviews, ranging from minor adjustment inthe existing process to entirely new solutions. These ideas correspond well to the indicatedareas and provide robust foundations for further discussion.Thus, findings from the research suggest several governance measures to systematicallyinvolve and engage diverse stakeholders in the Core network corridor implementationprocess. However, before introducing such measures, they should be assessed together withexisting governance measures, to avoid overlapping or contradictory initiatives, possiblyusing policy packaging approaches, where policies are combined and analysed together toachieve a desired overall outcome. Proposals for future research and practices are presented.

  • 3245.
    Öberg, Maria
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Nilsson, Kristina
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Johansson, Charlotta M.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Expected benefits and drawbacks of Baltic Sea European transport corridors: implications for complementary governance of TEN-T Core network corridors2018In: Cogent Business & Management, E-ISSN 2331-1975, Vol. 5, no 1, article id 1423870Article in journal (Refereed)
    Abstract [en]

    In this paper, stakeholders’ expected benefits and concerns are presented regarding the development of Core Network Corridors (CNCs) within the European transport initiative, the Trans-European Network for Transports. An interview study was conducted with 23 stakeholders from different parts of the society in the Baltic Sea area. The results show that stakeholders have a range of expectations, both positive and negative, for the development of the CNC. Stakeholders’ views were sorted into three categories based on the gathered data: matters that are already regulated; unregulated matters that often include vaguely defined responsibilities and require diverse stakeholder engagement for improvement; and matters for which there are concerns about negative outcomes. The results indicate (a) a need for cost-effective complementary governance, here described as additional governance measures to those regulated in the initial framework, (b) that a wider group of stakeholders than is currently involved is needed in the on-going implementation process. Additional regional and local level stakeholders, within and outside of the CNC, and private businesses, would enhance the benefits and/or mitigate negative implications of the developed CNCs, (c) an openness for complementary governance in the on-going CNC implementation process. This openness needs to be considered when developing models for policy packaging.

  • 3246.
    Öberg, Maria
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Nilsson, Kristina L
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Johansson, Charlotta
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Complementary governance for sustainable development in transport: the European TEN-T Core Network Corridors2018In: Article in journal (Refereed)
    Abstract [en]

    When implementing major European transport corridors, such as the Core network corridors (CNC) which is a part of the European Trans-European Network for Transports (TEN-T), the number of stakeholders affected is huge. A governance framework for the CNC’s implementation was introduced in EU Regulation No. 1315/2013, and is now being enacted. Sustainable development and stakeholder involvement are crucial areas in the implementation. This interview study investigated the need for complementary governance, here meaning governance in addition to the governance framework set in the regulation. The interviews involved 23 individuals from the Baltic Sea Region, who are affiliated to the four categories public authority, infrastructure organisation/company, private company and other organisation. The results confirm the importance of an inclusive approach. Further, the results showed a need to ensure that all three social, economic and ecological dimensions of sustainability are considered. Summarising the interview results, four areas for attention in the further CNC implementation process were identified: more and directed information, extended involvement of private sector transport stakeholders, extended involvement of regional and local stakeholders, and involvement of stakeholders located geographically outside the immediate corridor. Complementary governance can be a tool to address these areas, as governance structures and processes can involve stakeholders and steer towards desired outcomes. The interviewees own ideas for complementary governance are presented in this paper.

    The CNC implementation is currently an on-going process and these results will be further utilised in the process, as a basis for stakeholder discussions of changes in practice.

  • 3247.
    Öberg, Maria
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Nilsson, Kristina L.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Johansson, Charlotta
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    How to create a management structure for transport corridors2016In: Towards Innovative Freight and Logistics: Research for Innovative Transports Set / [ed] Corinne Blanquart; Uwe Clausen; Bernard Jacob, John Wiley & Sons, 2016, Vol. 2, p. 231-241Conference paper (Other academic)
  • 3248.
    Öberg, Maria
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Nilsson, Kristina L.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Johansson, Charlotta
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    How to create a management structure for transport corridors2014Conference paper (Refereed)
  • 3249.
    Öbrink, Emil
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Analysis and streamline the information flow at Baltic Sea Gateway2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    I takt med att informationen blir en allt större del av logistiken måste även den utvecklas och inte bara den fysiska delen. Hos Baltic Sea Gateway har informationslogistiken haft en stor utveckling på sidan som heter Fredriksskans medan Granudden som den andra sidan av vattnet heter har fortsatt som tidigare. I det här arbetet kommer informationsflödet på Granudden att ses över för att se vilka förbättringar som kan utföras på detta flöde som även kommer att stötta det fysiska flödet. Metoderna som använts för insamling av information till nulägesbeskrivningen och kartläggningen är intervjuer och observationer. Delar av informationen har fåtts ut genom tre av företagens interna system. Flödeskartläggningen visade att informationen på terminal Granudden har väldigt många steg samt att det finns två kundserviceavdelningar som båda hanterar information som rör det fysiska arbetet på terminal Granudden. Genom att ha två kundserviceavdelningar som sköter informationen på samma terminal sker en stor del onödig kommunikation och personalen i magasinet vet inte alltid vem de ska kontakta. En anledning till att informationsflödet är komplicerat hos Baltic Sea Gateway är för att det finns två olika kundserviceavdelningar där en endast tar hand om en kund medan den andra tar hand om all annan information inom och ut från företaget. Dessa två avdelningar kommunicerar med varandra och till viss del med samma personal i magasinen. Genom kartläggningen av informationsflödet på terminal Granudden har det visats att det finns en del problem i informationskedjan. Informationskedjan är onödigt komplex och en del arbetsuppgifter saknas samt att vissa uppgifter utförs i onödan. Denna rapport resulterar i ett antal förbättringsförslag där de två viktigaste rekommendationerna är att använda sig av en kundserviceavdelning istället för två samt att magasinsplanering måste ske för alla magasin på terminal Granudden.

  • 3250.
    Öhlin, Simon
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Urban and Regional Studies.
    Förklaringsmodell för cykelresor i Trondheim: Fysiska och demografiska faktorers betydelse för det geografiska resmönstret2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The work examines geographical variations of bicycle use in Trondheim municipality with the aim to create an understanding of what influences the use of bicycles and explain the geographical travel pattern for cycling. The work focuses on the how physical structures generates different transports effects. Where bicycle travels in Trondheim municipality are undertaken is described by using network analysis in ArcGIS, based on aggregated data from the travel habit survey (RVU) in 2009/2010. Trondheim municipality is divided into smaller geographical units (zoner) whose characteristics are described by 19 variables, categorized into 6 groups; Distance, Land use, Topography, Bicycle Facilities, Road characteristics and Demographic factors.

    By linear regression analysis in SPSS and ArcGIS Spatial Analyst, an explanatory model is elaborated. The variables

    distance to the regional center, workplace density, percentage separate bike paths and hilly terrain explains 78 percent of where cycle journeys are undertaken. Single variable with the highest explanatory power is degree of separate bicycle paths, which highlights the importance of infrastructure investment for bicyclists.

    Based on the result, recommendations are given on improvements of the bicycle routes in Trondheim, followed by a discussion of strategies for planning cycle routes.

6263646566 3201 - 3250 of 3271
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