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  • 1.
    Aaboen, Lise
    NTNU, Trondheim.
    BATON-CHANGING ON EGGSHELLS – TRANSFERRING SUPPLIER RELATIONSHIPS WHEN MOVING PRODUCTION2014Conference paper (Refereed)
    Abstract [en]

    Production transfers are a result of outsourcing and offshoring decisions. Though, because of

    the strategic focus of the outsourcing literature have not the operational issues of how

    relationship development between sender, receiver and raw material been fully depicted. The

    purpose of the present paper is to explore relationship development connected to transfer of

    raw material supplies responsibility during transfer of production. To fulfil the purpose, four

    different production transfers were studied: three from Sweden to China, Romania and

    Hungary respectively and one transfer from Holland to Sweden. We can see that the

    dependence and power shifts gradually between the sender and the receiver and the

    relationship between them sets the arena for what relationship is developed between the

    receiver and the raw material suppliers. Furthermore, short social distances can over bridge

    cultural and technological distances to some extent, because it motivates to take the

    relationship into a more developed state.

  • 2.
    Aaboen, Lise
    et al.
    Department of Industrial Economics and Technology Management, Norwegian University of Science and Technology (NTNU), Trondheim, Norway.
    Fredriksson, Anna
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    The relationship development aspect of production transfer2016In: Journal of Purchasing and Supply Management, ISSN 1478-4092, E-ISSN 1873-6505, Vol. 22, no 1, p. 53-65Article in journal (Refereed)
    Abstract [en]

    Production transfers are a result of outsourcing and offshoring decisions. Because of the strategic focus of the outsourcing literature, the operational issues of relationship development between sender and receiver and its impact on the transfer progress have not been fully depicted. The purpose of the present paper is to explore relationship development during production transfer. To fulfil this purpose, we studied three different production transfers and derived four propositions for further testing. Our main conclusions included that dependence and power gradually shift between the sender and the receiver and that the relationship between them sets the arena for what types of relationships can be developed between the receiver and the suppliers. Furthermore, short social distances can bridge cultural and technological distances to some extent, because it motivates the actors to bring their relationship into a more developed state. Finally, we noticed that the headquarters’ involvement can work both as an inhibitor as well as a converter.

  • 3.
    Aban, Kevin
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Göst, Jens
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Analysis of transports with pharmaceuticals on Arlanda airport2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Rapporten syftar till att kartlägga och analysera dagens transportflöde av läkemedel på fraktområdet Cargo City på Arlanda. Cargo Center och APH Logistics är två fraktagenter som har sin verksamhet på Cargo City. Observera att Cargo City och Cargo Center inte har samma innebörd. Cargo Center och APH Logistics erbjuder genom nära samarbete transport och hantering av temperaturkänsligt gods, som till exempel läkemedel. Läkemedel är värdefullt gods som kräver särskild skötsel vid transport, hantering och förvaring. Det ställer stränga krav på samtliga aktörer i försörjningskedjan. Genom studiebesök och intervjuer har författarna kartlagt det befintliga flödet av läkemedel. SACT, ett åkeri och dotterbolag till Cargo Center, utför transporten av godset till Cargo City med nerkylda lastbilar. APH Logistics omlastningsterminal på Cargo City är temperaturkontrollerad, vilket innebär att läkemedelsgodset förvaras och lastats i flygcontainrar där. Det färdiglastade godset forslas sedan vidare till Cargo Centers terminal. Där sker vikt- och volymkontroll av godset, det registreras i olika datasystem och slutligen märks det med etiketter, så som flygfraktsedeln. Mycket av godset som hanteras på Arlanda körs med lastbil till andra flygplatser och destinationer runt om i Europa istället för att flygfraktas direkt från flygplatsen. Dessutom hanteras och förvaras inte allt läkemedelsgods under temperaturkontrollerade former. En totalkostnadsanalys har gjorts för att jämföra olika transportflödesscenarion. Dessutom har författarna identifierat den kundservice Cargo Center och APH Logistics bör erbjuda kunden. Den bygger på kvalitativa resonemang. Resultatet av rapporten är författarnas rekommendation till företagen av hur de bör gå tillväga i framtiden. Den ger både kortsiktiga och långsiktiga tips.

  • 4.
    Abrahamsson, Mats
    Linköping University, Department of Management and Engineering, Logistics & Quality Management. Linköping University, Faculty of Science & Engineering.
    Logistik för ökad svensk konkurrenskraft: Forsknings- och innovationsagenda för framtidens logistik2013Report (Other academic)
    Abstract [sv]

    Framtidens logistik står inför mycket stora utmaningar som har direkt bäring på svenska företags och organisationers förmåga till tillväxt, hållbarhet och konkurrenskraft. 

    Det står utom all tvivel att logistikens betydelse kommer att öka ännu mer i framtiden. Vinnare på de globala, rörliga marknaderna kommer ett vara de flödeseffektiva företagen, som har förmåga att hantera förändringarna på marknaden med en effektiv logistik som grund. För att lyckas behövs ett Logistiklyft för Sverige, med ett medvetet fokus på att utveckla de dynamiska förmågorna i företag och organisationer. Detta gäller i de allra flesta branscher och typ av företag.

    Den här innovations- och forskningsagendan utgår från den svenska traditionen och internationellt sett unika kunskapen och förmågan att med en systemsyn som grund designa, utveckla och styra komplexa system där flera olika kompetenser samverkar. Logistikens systemkunskap handlar om att lära sig att utforma och styra omfattande och allt mer komplexa försörjningskedjor (supply chains) från råvara till slutkund i syfte att öka svenska företags internationella konkurrenskraft och förmåga att växa på ett miljömässigt och ekonomiskt hållbart sätt

    Agendan adresserar behovet av kompetens och kunskap för mer innovativ logistikutveckling som följer:

    • Utveckling av kunskap om nya och mer innovativa logistiksystem och modeller för industri & handel 
    • Tjänsteutveckling för transport/logistik och IT-företag som stöd för mer innovativa logistiksystem, men också att ta till vara och stimulera den omfattande tjänsteutveckling som finns i förnyelsen av svenskt näringsliv, t ex mot högre grad av e-handel. 
    • Tillämpning av befintliga logistikkunskaper för områden och sektorer i behov av ett logistiklyft och ökad flödeseffektivitet, t.ex. logistik för små- och medelstora företag (SME) med fokus på HUR (genomförandeprocesser) istället för VAD (utformning av koncept och modeller). 
    • Utveckling av kunskaper om hur logistiksystem kan bidra till en hållbar utveckling, såväl miljömässigt som socialt.
    • Utveckling av kunskap om och tillämpning av logistiklösningar med primär samhällsnytta, t ex sjukvårdslogistik och citylogistik samt effektiv och hållbar försörjning av livsmedel, energi etc.

    Den här forsknigs- och innovationsagendan är utvecklad i samarbete mellan Linköpings Universitet, Lunds Tekniska Högskola, Chalmers Tekniska Högskola och en lång rad företag där Axis, SKF, Volvo och Nobel Biocare har funnits med i projektets styrgrupp. 

    Agendan finns endast som PDF. Kontakta Mats Abrahamsson, Linköpings Universitet. mats.abrahamsson@liu.se

  • 5.
    Abrishami, Mahdi
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Dynamic Link Flow Estimation according to Historical Travel Times2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Vast application of ITS and the availability of numerous on-road detection devices has resulted in variety of alternative data sources to be exploited and used in the field of traffic modelling. In this thesis, historical travel times, as an alternative data source, is employed on the developed method to perform dynamic network loading. The developed method, referred to as DNLTT, uses the share of each route available in the route choice set from the initial demand, as well as link travel times to perform the network loading. The output of the algorithm is time-dependent link flows. DNLTT is applied on Stockholm transportation network, where it is expected to have variation in link travel times in different time-periods, due to network congestion. In order to calculate the route shares, a time-sliced OD matrix is used. The historical travel times and the routes in the route choice set are extracted from an existing route planning tool. An available logit model, which considers the route travel time as the only logit parameter, is used for the route share calculation and the network loading is performed according to 2 different methods of DNLTT and DL. The evaluation of results is done for a toy network, where there happen different network states in different time-periods. Furthermore, the model output from Stockholm case study is analyzed and evaluated. The dynamic behavior of DNLTT is studied by analysis of link flows in different time-periods. Furthermore, the resulting link flows from both network loading methods are compared against observed link flows from radar sensors and the statistical analysis of link flows is performed accordingly. DNLTT exhibits a better performance on the toy network compared to DL, where the increasing link travel times cause the link flows to decline in different time-periods. However, the output of the developed method does not resemble the observed link flows for the investigated links in Stockholm case study. It is strongly believed, that the performance of DNLTT on the investigated transportation network potentially improves, in case the historical travel times better resemble the network dynamics. In addition to a more reliable data set, an OD adjustment process in all the time-periods is believed to generate better model output.

  • 6.
    Adedokun, Adeyemi
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Application of Road Infrastructure Safety Assessment Methods at Intersections2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Traffic safety at intersections is a particularly difficult phenomenon to study, given the fact that accidents occur randomly in time and space thereby making short-term measurement, assessment and comparison difficult. The EU directive 2008/96/EC introduced road infrastructure safety management, which offers a five layer structure for developing safer road infrastructure has been used to develop tools for accident prediction and black spot management analysis which has been applied in this work to assess the safety level of intersections in Norrköping city in Sweden. Accident data history from STRADA (Swedish Traffic Accident Data Acquisition) and the network demand model for Norrköping city were used to model black spots and predict the expected number of accidents at intersections using PTV Visum Safety tool, after STRADA accident classification was restructured and the Swedish accident prediction model (APM) was configured and tested to work within the tool using the model from the Swedish road administration (SRA). The performance of the default (Swiss) and the Swedish APM was compared and identified locations with the high accident records, predicted accident counts and traffic volumes were audited using qualitative assessment checklist from Street-Audit tool. The results from these methods were analysed, validated and compared. This work provides recommendations on the used quantitative and qualitative methods to prevent accident occurrence at the identified locations.

  • 7.
    Adelsköld, Astrid
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Review of general demand responsive transport in Sörmland county2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Sörmlands län består till stor del av landsbygd där en kostnadseffektiv kollektivtrafik är svår att uppnå eftersom resandeunderlaget och därmed även efterfrågan normalt är låg. I dessa områden finns dock potential att uppnå en hållbar kollektivtrafik med hjälp av anropsstyrda trafikformer. I detta projekt utreddes dels en övergång av turer i landsbygdslinjetrafiken till allmän anropsstyrd trafik och dels en samordning av den allmänna och särskilda anropsstyrda kollektivtrafiken. En generell metod för val mellan fast linjetrafik och anropsstyrd linjelagd trafik utvecklades, vilken bestod av enkla tumregler för utvärdering av turer med regelbundet låg efterfrågan i landsbygdslinjetrafiken. Samordningen bestod av att utreda effekterna av att kompletteringsresor planerades och utfördes med samma fordon som den särskilda anropsstyrda kollektivtrafiken. Då kompletteringstrafiken får en högre kostnadseffektivitet genom samordning med den särskilda kollektivtrafiken kan denna användas som en flexibel ersättning där turutbudet i landsbygdslinjetrafiken behöver minska. En kostnadseffektivisering av landsbygdslinjetrafiken där turutbudet anpassas bättre till efterfrågan tillåter därmed en satsning av resurser till kompletteringstrafiken. Detta för att i enlighet med kollektivtrafikmyndighetens mål skapa en attraktiv kollektivtrafik för hållbar tillväxt och utveckling i Sörmlands län.

  • 8.
    Adjiashvili, David
    et al.
    ETH, Switzerland.
    Bosio, Sandro
    ETH, Switzerland.
    Li, Yuan
    Lund University, Sweden.
    Yuan, Di
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Exact and Approximation Algorithms for Optimal Equipment Selection in Deploying In-Building Distributed Antenna Systems2015In: IEEE Transactions on Mobile Computing, ISSN 1536-1233, E-ISSN 1558-0660, Vol. 14, no 4, p. 702-713Article in journal (Refereed)
    Abstract [en]

    We consider a combinatorial optimization problemin passive In-Building Distributed Antenna Systems (IB-DAS) deployment for indoor mobile broadband service. These systems have a tree topology, in which a central base station is connected to a number of antennas located at tree leaves via cables represented by the tree edges. Each inner node corresponds to a power equipment, of which the available types differ in the number of output ports and/or by power gain at the ports. This paper focuses on the equipment selection problemthat amounts to, for a given passive DAS tree topology, selecting a power equipment type for each inner node and assigning the outgoing edges of the node to the equipment ports. The performance metric is the power deviation at the antennas from the target values. We consider as objective function the minimization of either the total or the largest power deviation over all antennas. Our contributions are the development of exact pseudo-polynomial time algorithms and (additive) fully-polynomial time approximation schemes for both objectives. Numerical results are provided to illustrate the algorithms. We also extend some results to account for equipment cost.

  • 9.
    Adolfsson, Lovisa
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Nilsson, Rebecca
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Collection structure design of deposited PET bottles and aluminium cans in northern Sweden2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Returpack är ansvariga för Sveriges retursystem av tomma PET-flaskor och aluminiumburkar där insamling och hantering av förpackningar är en stor del av verksamheten. Transport av tomma förpackningar från butik till Returpacks fabrik i Norrköping sker huvudsakligen i form av lösvikt (bulklast) av Returpack. Övriga transporter av förpackningar sker i kartong eller säck där dryckesleverantörer sköter insamlingen. Syftet med denna studie är att skapa och undersöka olika typer av inhämtningsstrukturer för tomma förpackningar, där Returpack strävar efter att på ett kostnadseffektivt och miljömässigt sätt sköta inhämtningen samt öka kontrollen över flödet. I studien kommer fem områden i norra Sverige att undersökas, vilka skiljer sig från övriga områden i Sverige då dessa kännetecknas av långa avstånd mellan butiker samt låga volymer av förpackningar. I studien utförs ruttplanering av lösviktsinsamling samt totalkostnadberäkningar för varje område, där ett antal scenarier skapats med olika typer av inhämtningsstrukturer. I scenarierna varieras antalet butiker, mellanlager, ruttider samt insamlingsbilar. Utöver detta undersöks även fyra olika hubblösningar där förpackningarna gör en övergång från kartong- och säckflödet till lösviktsflödet. Resultaten av ruttplanerningarna visar att två av områdena har en hög belastning där antalet insamlingsbilar behöver ökas. Totalkostnadsberäkningarna tyder på att det går att sänka totalkostnaden i två av områdena genom att öka lösviktsinsamlingen. I de övriga tre områdena ger den nuvarande strukturen den lägsta totalkostnaden. Resultaten visar också att antalet fordonskilometer kan minska genom att addera ytterligare ett mellanlager i två av områdena. I studien visas det också att hubbar kan sänka kostnader för Returpack och minska antalet inkommande kartonger och säckar till fabriken. Att införa hubbar minskar också antalet fordonskilometer med mer än 50 %.

  • 10.
    Aghighi, Meysam
    et al.
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Bäckström, Christer
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Cost-optimal and Net-benefit Planning: A Parameterised Complexity View2015In: 24th International Joint Conference on Artificial Intelligence (IJCAI-15), IJCAI-INT JOINT CONF ARTIF INTELL, ALBERT-LUDWIGS UNIV FREIBURG GEORGES-KOHLER-ALLEE, INST INFORMATIK, GEB 052, FREIBURG, D-79110, GERMANY , 2015, p. 1487-1493Conference paper (Refereed)
    Abstract [en]

    Cost-optimal planning (COP) uses action costs and asks for a minimum-cost plan. It is sometimes assumed that there is no harm in using actions with zero cost or rational cost. Classical complexity analysis does not contradict this assumption; planning is PSPACE-complete regardless of whether action costs are positive or non-negative, integer or rational. We thus apply parameterised complexity analysis to shed more light on this issue. Our main results are the following. COP is W[2]-complete for positive integer costs, i.e. it is no harder than finding a minimum-length plan, but it is para-NPhard if the costs are non-negative integers or positive rationals. This is a very strong indication that the latter cases are substantially harder. Net-benefit planning (NBP) additionally assigns goal utilities and asks for a plan with maximum difference between its utility and its cost. NBP is para-NP-hard even when action costs and utilities are positive integers, suggesting that it is harder than COP. In addition, we also analyse a large number of subclasses, using both the PUBS restrictions and restricting the number of preconditions and effects.

  • 11.
    Ahlberg, John
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Cruz Wolter Håkansson, Christoffer
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Identification, mapping and control of non-structure-bound materials2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    I Saab Aerostructures tillverkning av flygplansdelar, används icke strukturbundet material, det vill säga material som inte har en angiven kvantifierad förbrukning per tillverkad enhet eller material vars angivna kvantifierade förbrukning per tillverkad enhet inte stämmer överens med verklig förbrukning. Personal på inköpsavdelningen vet i vissa fall inte var ett specifikt icke strukturbundet material förbrukas, alltså vilka tillverkningsavdelningar eller flygplansdelar som förbrukar materialet. Likaså saknas övergripande och gemensamma rutiner för hur material som klassas som icke strukturbundet material planeras och lagerstyrs. För att identifiera problemområden i materialförsörjningen genomfördes en flödeskartläggning för att identifiera vilka olika typer av icke strukturbundet material som används i Saab Aerostructures produktion samt hur dessa lagerstyrs mellan lager och buffertlager i produktion. Under flödeskartläggningen definierades sex olika materialgrupper tillhörande icke strukturbundet material. För att lagerstyra de identifierade materialgrupperna av icke strukturbundet material används idag åtta stycken lagerstyrningsmetoder. Saab Aerostructures har anlitat tredjepartslogistiker för att sköta merparten av dagens lagerstyrning. Lagerstyrningsmetoderna skiljer sig åt beroende på tredjepartslogistiker och materialgrupp av icke strukturbundet material. Resultatet från genomförd kartläggning och analys påvisar att det finns förbättringspotential i flera utav dessa lagerstyrningsmetoder, samt att det är möjligt att reducera antalet lagerstyrningsmetoder genom att använda samma lagerstyrningsmetod för snarlika materialgrupper av icke strukturbundet material. Genomförd analys påvisar även behovet av ett förbättrat informationsflöde mellan beredning, inköp och produktion, när det gäller hanteringen av icke strukturbundet material. Konkreta åtgärder i form av rekommendationer, för att förbättra lagerstyrningen av icke strukturbundet material, presenteras i slutet av denna rapport.  

  • 12.
    Ahlepil, Erik
    et al.
    Linköping University, Department of Management and Engineering, Logistics & Quality Management.
    Björck, Joel
    Linköping University, Department of Management and Engineering, Logistics & Quality Management.
    Evaluating Distribution Structures for Overseas Export of Frozen Food.2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The meat producers of the western world needs to develop their export organizations and to streamline their physical distribution in order to take new market shares on the fast growing overseas markets. HKScan is one of those meat producing companies, the group has businesses in Finland, Sweden, Denmark and the Baltic countries. A part of their sales goes frozen on overseas export by container sea freight. Lately the logistics management of HKScan has been interested in investigating the effects of centralizing the physical distribution for the overseas export from Sweden and Denmark. This leads to the purpose of this study, which is:

     “For HKScan, develop and apply a model that evaluates distribution structures for overseas export of frozen food regarding total cost, delivery service, environmental impact and regulations.”

    The case study included comparison between the current distribution structure for HKScan and three pre-determined scenarios. The current setup consists of multiple warehouses in both countries. In the first scenario the distribution structure is centralized to include one warehouse per country. In the second scenario, the total export flow of products from both Sweden and Denmark is redirected and centralized to one warehouse in Denmark. In the third scenario, the total export flow of products from both Sweden and Denmark is instead redirected and centralized to one warehouse in Sweden.

    To evaluate and compare the different distribution structures a general model was first created by combining different theoretical models and adapting them to the context of overseas distribution for frozen food. The study then included the three phases of developing the model to fit the case company, applying the model on the case company and then to finally evaluating the model.

    The resulting model, which was the outcome of the development process, can be seen below. The model illustrates the different included elements.

    By then applying the model onto the case company, HKScan, it was found that a centralization to a joint warehouse in Denmark would make total cost savings of several percents. In addition, this scenario would increase the total service level. However, the environmental impact would be increased due to long cross-border road transport distances and longer land and sea transports from the warehouse. In addition, it was not possible to fully investigate whether such a distribution would be possible from a regulatory point of view.  A centralization in each country would have minor regulatory issues, it would lead to the smallest environmental impact and have a slight increase in service levels as well as a reduction for the total cost of one percent.

    The evaluation of the model showed that it produces reasonable results with the regulatory elements being the hardest to evaluate for the different scenarios. Regarding the detail level, the veterinary element could be accounted for by the warehousing element and the sea freight element split into transport from warehouse to domestic port and sea freight from domestic port to the destination port. The box-model, containing twelve elements, can be seen as generalizable for evaluating distribution structures in similar contexts, Overseas export of frozen food. However, the calculation performed within the model do probably only apply to the specific scenarios in the study.

  • 13.
    Ahlstrom, Christer
    et al.
    Swedish Natl Rd and Transport Res Inst VTI, Linkoping, Sweden.
    Anund, Anna
    Not Found:Linkoping Univ, Rehabil Med, Linkoping, Sweden; Swedish Natl Rd and Transport Res Inst VTI, Linkoping, Sweden.
    Fors, Carina
    Swedish Natl Rd and Transport Res Inst VTI, Linkoping, Sweden.
    Akerstedt, Torbjorn
    Stockholm Univ, Sweden; Karolinska Inst, Sweden.
    The effect of daylight versus darkness on driver sleepiness: a driving simulator study2018In: Journal of Sleep Research, ISSN 0962-1105, E-ISSN 1365-2869, Vol. 27, no 3, article id UNSP e12642Article in journal (Refereed)
    Abstract [en]

    Driver sleepiness studies are often carried out with alert drivers during daytime and sleep-deprived drivers during night-time. This design results in a mixture of different factors (e.g. circadian effects, homeostatic effects, light conditions) that may confound the results. The aim of this study was to investigate the effect of light conditions on driver sleepiness. Thirty young male drivers (23.6 +/- 1.7years old) participated in a driving simulator experiment where they drove on a rural road. A 2x2 design was used with the conditions daylight versus darkness, and daytime (full sleep) versus night-time (sleep deprived). The results show that light condition had an independent effect on the sleepiness variables. The subjective sleepiness measured by Karolinska Sleepiness Scale was higher, lateral position more left-oriented, speed lower, electroencephalogram alpha and theta higher, and blink durations were longer during darkness. The number of line crossings did not change significantly with light condition. The day/night condition had profound effects on most sleepiness indicators while controlling for light condition. The number of line crossings was higher during night driving, Karolinska Sleepiness Scale was higher, blink durations were longer and speed was lower. There were no significant interactions, indicating that light conditions have an additive effect on sleepiness. In conclusion, Karolinska Sleepiness Scale and blink durations increase primarily with sleep deprivation, but also as an effect of darkness. Line crossings are mainly driven by the need for sleep and the reduced alertness at the circadian nadir. Lane position is, however, more determined by light conditions than by sleepiness.

  • 14.
    Ahlström, Christer
    et al.
    VTI, Swedish Natl Rd and Transport Res Inst, Linkoping, Sweden.
    Anund, Anna
    Linköping University, Department of Medical and Health Sciences, Division of Community Medicine. Linköping University, Faculty of Medicine and Health Sciences. VTI, Swedish Natl Rd and Transport Res Inst, Linkoping, Sweden.
    Fors, Carina
    VTI, Swedish Natl Rd and Transport Res Inst, Linkoping, Sweden.
    Åkerstedt, Torbjorn
    Stockholm Univ, Sweden; Karolinska Inst, Sweden.
    Effects of the road environment on the development of driver sleepiness in young male drivers2018In: Accident Analysis and Prevention, ISSN 0001-4575, E-ISSN 1879-2057, Vol. 112, p. 127-134Article in journal (Refereed)
    Abstract [en]

    Latent driver sleepiness may in some cases be masked by for example social interaction, stress and physical activity. This short-term modulation of sleepiness may also result from environmental factors, such as when driving in stimulating environments. The aim of this study is to compare two road environments and investigate how they affect driver sleepiness. Thirty young male drivers participated in a driving simulator experiment where they drove two scenarios: a rural environment with winding roads and low traffic density, and a suburban road with higher traffic density and a more built-up roadside environment. The driving task was essentially the same in both scenarios, i.e. to stay on the road, without much interaction with other road users. A 2 x 2 design, with the conditions rural versus suburban, and daytime (full sleep) versus night-time (sleep deprived), was used. The results show that there were only minor effects of the road environment on subjective and physiological indicators of sleepiness. In contrast, there was an increase in subjective sleepiness, longer blink durations and increased EEG alpha content, both due to time on task and to night-time driving. The two road environments differed both in terms of the demand on driver action and of visual load, and the results indicate that action demand is the more important of the two factors. The notion that driver fatigue should be countered in a more stimulating visual environment such as in the city is thus more likely due to increased task demand rather than to a richer visual scenery. This should be investigated in further studies.

  • 15.
    Ahlström, Christer
    et al.
    Swedish National Rd and Transport Research Institute VTI, S-58195 Linkoping, Sweden.
    Kircher, Katja
    Linköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences. Swedish National Rd and Transport Research Institute VTI, S-58195 Linkoping, Sweden.
    A Generalized Method to Extract Visual Time-Sharing Sequences From Naturalistic Driving Data2017In: IEEE transactions on intelligent transportation systems (Print), ISSN 1524-9050, E-ISSN 1558-0016, Vol. 18, no 11, p. 2929-2938Article in journal (Refereed)
    Abstract [en]

    Indicators based on visual time-sharing have been used to investigate drivers visual behaviour during additional task execution. However, visual time-sharing analyses have been restricted to additional tasks with well-defined temporal start and end points and a dedicated visual target area. We introduce a method to automatically extract visual time-sharing sequences directly from eye tracking data. This facilitates investigations of systems, providing continuous information without well-defined start and end points. Furthermore, it becomes possible to investigate time-sharing behavior with other types of glance targets such as the mirrors. Time-sharing sequences are here extracted based on between-glance durations. If glances to a particular target are separated by less than a time-based threshold value, we assume that they belong to the same information intake event. Our results indicate that a 4-s threshold is appropriate. Examples derived from 12 drivers (about 100 hours of eye tracking data), collected in an on-road investigation of an in-vehicle information system, are provided to illustrate sequence-based analyses. This includes the possibility to investigate human-machine interface designs based on the number of glances in the extracted sequences, and to increase the legibility of transition matrices by deriving them from time-sharing sequences instead of single glances. More object-oriented glance behavior analyses, based on additional sensor and information fusion, are identified as the next future step. This would enable automated extraction of time-sharing sequences not only for targets fixed in the vehicles coordinate system, but also for environmental and traffic targets that move independently of the drivers vehicle.

  • 16.
    Ahlström, Christer
    et al.
    Swedish National Rd and Transport Research Institute VTI, S-58195 Linkoping, Sweden.
    Kircher, Katja
    Linköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences. Swedish National Rd and Transport Research Institute VTI, S-58195 Linkoping, Sweden.
    Changes in glance behaviour when using a visual eco-driving system - A field study2017In: Applied Ergonomics, ISSN 0003-6870, E-ISSN 1872-9126, Vol. 58, p. 414-423Article in journal (Refereed)
    Abstract [en]

    While in-vehicle eco-driving support systems have the potential to reduce greenhouse gas emissions and save fuel, they may also distract drivers, especially if the system makes use of a visual interface. The objective of this study is to investigate the visual behaviour of drivers interacting with such a system, implemented on a five-inch screen mounted above the middle console. Ten drivers participated in a real world, on-road driving study where they drove a route nine times (2 pre-baseline drives, 5 treatment drives, 2 post-baseline drives). The route was 96 km long and consisted of rural roads, urban roads and a dual-lane motorway. The results show that drivers look at the system for 5-8% of the time, depending on road type, with a glance duration of about 0.6 s, and with 0.05% long glances (amp;gt;2s) per kilometre. These figures are comparable to what was found for glances to the speedometer in this study. Glance behaviour away from the windscreen is slightly increased in treatment as compared to pre- and post-baseline, mirror glances decreased in treatment and post-baseline compared to pre-baseline, and speedometer glances increased compared to pre-baseline. The eco-driving support system provided continuous information interspersed with additional advice pop-ups (announced by a beep) and feedback pop-ups (no auditory cue). About 20% of sound initiated advice pop-ups were disregarded, and the remaining cases were usually looked at within the first two seconds. About 40% of the feedback pop-ups were disregarded. The amount of glances to the system immediately before the onset of a pop-up was clearly higher for feedback than for advice. All in all, the eco-driving support system under investigation is not likely to have a strong negative impact on glance behaviour. However, there is room for improvements. We recommend that eco-driving information is integrated with the speedometer, that optional activation of sound alerts for intermittent information is made available, and that the pop-up duration should be extended to facilitate self-regulation of information intake. (C) 2016 Elsevier Ltd. All rights reserved.

  • 17.
    Ahlström, Mattias
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Development of an Attractive Network for Regional Bus Traffic in Dalarna County2015Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Även om direktbusstrafiken i Dalarnas län redan i dagsläget trafikerar relativt raka och snabba linjesträckningar anser länstrafikbolaget Dalatrafik att det finns potential till att ytterligare sänka restiderna för att locka fler resenärer. Fyra av länets viktigaste direktbusslinjer har därför studerats och för var och en av dessa har ett antal förändringsåtgärder tagits fram. Målet med förändringsåtgärderna har varit att, i första hand, åstadkomma en rakare linjesträckning och utreda hur mycket restiden skulle komma att förändras om bussen istället kör den nya vägen. Utifrån befintlig resandestatistik över hur många resenärer som reser på varje sträcka har den totala tidsbesparingen för samtliga förändringsåtgärder per linje beräknats och detta har givits ett monetärt värde. Genom täckningsanalyser har befolkningen inom upptagningsområdet kring varje hållplats beräknats, detta för att visa hur tillgängligheten till respektive linje förändras efter ett eventuellt införande av de föreslagna åtgärderna.

  • 18.
    Ahmad, Ban
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Vieglins, Gustav
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    A energy and cost comparison between a BBR and a passive apartment building2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Idag ställer samhället och konsumenterna allt större krav på klimatsmarta boenden för att minska energianvändningen. Trots det byggs fortfarande till stor del traditionella hus efter Boverkets byggregler. På uppdrag av WSP studerar denna rapport hur energiåtgången hos ett befintligt flerbostadshus i Stockholm, byggt efter BBR, hade sett ut om det uppförts för att fylla kravspecifikationen för passivhus enligt FEBY12. Samt hur livscykelkostnaderna hade skiljt sig för de två husen.

    Studien inleddes med en datainsamling av för det befintliga flerbostadshusets areor samt Uvärdena och följs upp med simuleringar av flerbostadshuset i beräkningsprogrammet Energihuskalkyl. Datorberäkningarna jämfördes med manuella beräkningar för att säkerställa värmeförlusttalet samt andelen köpt energi. Varefter flerbostadshuset anpassades med Kingspans detaljbibliotek för att uppfylla FEBY12s passivhuskrav och följdes upp med samma dator- och manuella beräkningar. Där de båda resultaten presenteras och jämförs.

    I rapportens andra del undersöks och jämförs de två flerbostadshusens livscykelkostnader, sett till investerings-, drifts- och underhållskostnader. Då beställaren sekretessbelagt de verkliga kostnaderna antogs de verkliga kostnaderna för det befintliga huset från Statistiska Centralbyrån. För att beräkna det teoretiska passivhusets investeringskostnader beräknades materialkostnaderna för de båda husen efter de givna ritningarna. Där skillnaden i materialkostnaderna adderades till investeringskostnaden för det passiva flerbostadshuset.

    Underhållskostnaderna antogs till detsamma för det passiva flerbostadshuset samtidigt som att driftskostnaderna sänktes procentuellt med den minskade mängden köpt energi från energiberäkningarna.

  • 19.
    Aid, Graham
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell ekologi.
    Brandt, Nils
    KTH, Skolan för industriell teknik och management (ITM), Industriell ekologi.
    Improvement of aggregate cycles in Stockholm and the Baltic Region: Activities and results of the BRA initiative2012In: Proceedings of the 8th International conference on Sustainable management of waste and recycled materials in construction, Gothenburg, Sweden, 30 May - 1 June 2012 / [ed] M. Arm, C. Vandecasteele, J. Heynen, P. Suer and B. Lind, Swedish Geotechnical Institute , 2012, p. 1-9Conference paper (Refereed)
    Abstract [en]

    From 2009 until 2011 project BRA (Bygg-och Rivningsavfall i Stockholms Län) “Construction and Demolition (C&D) waste in Stockholm County” was coordinated from the division of Industrial Ecology, KTH. This project was focused on actively improving (from plural perspectives) the cycles of C&D (specifically non-metallic inert) materials in the region. In response to the normative aim and inter-systems complexity, a highly participative action research procedure was adopted. Through processes of network communication, workshops, a course, and an international symposium - a number of issues (such as market development, recycled product quality, greenhouse gas impacts, collaborative planning, and statistics) were prioritized, researched, and acted upon. Indicators for measuring progress in selected areas were developed and preliminary action plans created. At a final co-organized symposium Swedish delegates laid the groundwork for the establishment of a Swedish C&D recycling b ranch organization. This initiative of continued collaboration between and within sectors is seen as a vehicle for the priorities and action requirements identified in BRA to be further enabled and held in focus. Furthermore, these actors taking ownership of the process is seen as a success in accordance to the original aims and the need for further cycles of evaluation, planning, and action.

  • 20.
    Aid, Graham
    et al.
    Division of Industrial Ecology, The Royal Institute of Technology (KTH), Stockholm, Sweden / Ragn Sells AB, Sollentuna, Sweden.
    Brandt, Nils
    Division of Industrial Ecology, The Royal Institute of Technology (KTH), Stockholm, Sweden.
    Lysenkova, Mariya
    Rampage Consulting Ltd., Stockholm, Sweden.
    Smedberg, Niklas
    Division of Industrial Ecology, The Royal Institute of Technology (KTH), Stockholm, Sweden.
    Looplocal - a heuristic visualization tool to support the strategic facilitation of industrial symbiosis2015In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 98, p. 328-335Article in journal (Refereed)
    Abstract [en]

    Industrial symbiosis (IS) developments have been differentiated as self-organized, facilitated, and planned. This article introduces a tool, Looplocal, which has been built with objectives to support the strategic facilitation of IS. Looplocal is a visualization tool built to assist in 1) Simplifying the identification of regions susceptible to new industrial symbiosis facilitation activities 2) Enabling proactive and targeted marketing of potential exchanges to key actors in specific regions and 3) Assisting facilitators to assess the various strategies and consequential engagement and analysis methodologies suitable for additional IS development in specific regions. The tool compares industrial symbiosis data and estimated regional material and energy flows (on a facility level) to identify potential IS transfer information along with key stakeholder and network data. The authors have performed a proof of concept run of this tool on Sweden. In its early stages of application the method has given results seen as useful for identifying regions susceptible to the investment of symbiosis facilitators' time and resources. The material focus and customization possibilities for the tool show potential for a spectrum of potential facilitators: from waste management companies to national or regional authorities. In conjunction with long term business models, such a tool might be utilized throughout an adaptive chain of facilitation activities and aims.

  • 21.
    Akgul, Veysel Dogan
    Linköping University, Department of Science and Technology.
    A Study on Children and School Pedestrians’ Safety in2008Independent thesis Advanced level (degree of Magister), 20 points / 30 hpStudent thesis
    Abstract [en]

    Child pedestrian safety is one of the biggest safety issues regarding planning of a well arranged urban traffic. The fact that vulnerable road users suffer most from traffic incidents also raises concern for children. Children need special care while considering traffic safety. The factors are various that they differ from adults by many aspects. For their physically smaller size, immature ability to judge the traffic situations, lack of experience about traffic and mental deficiencies like losing concentration after short periods, they are much more susceptible to the traffic hazards than adults. Various studies have been carried and many applications regarding child and school pedestrian safety worldwide and the most hazardous periods were found as afternoon hours. Age factor generally is flexible but as the child grows older, mobility increases and risks become larger. The risk factors also include the social and economical environment that children living in good life standards suffer less than those are not. Education is also crucial on adopting the sense of road safety on children’s perspective. Simulation based studies have proved to be effective in order to draw child’s attention to the subject, however it should be combined with field trips to gain a more realistic and solid idea about the matter. Besides, engineering measures rise up as another milestone where roadside and land use planning is important. Traffic calming measures have proved to be effective to warn road users and thus form a safer traffic environment for children. Special applications for school zones such as flashing lights, narrowed crossways or 30km/h areas have been effective. The case study concerns the evaluation of child pedestrian safety in the vicinities of various accidents previously happened in Norrköping. Two methods were used to examine the degree of safety for the places of incidents. For locations near an intersection, road safety audit and traffic conflicts technique were applied, while, for the incident points along streets, only road safety audit technique was used. It is stated that, because of the multivariable aspect of the problem, collective application of various safety evaluation solutions would give better idea on the risk of the location and possible improvements for the future.

  • 22.
    Akililu, Meaza Negash
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Verification of Rural Traffic Simulator, RuTSim 22012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Traffic models based on micro-simulation are becoming increasingly important as traffic analysistools. Due to the detailed traffic description, different micro-simulation models are needed tosimulate different traffic environments. The Rural Traffic Simulator, RuTSim, is a unique microtrafficsimulation model for traffic on rural roads. RuTSim is developed at VTI with support fromthe Swedish Transport Administration. Currently, a new version of the RuTSim model has beenimplemented based on the earlier one but with some enhancements. Due to these enhancements,the new implementation of RuTSim should be verified before being used to analyze real worldproblems.

    In this master’s thesis, a verification of the new implementation of the RuTSim model, RuTSim 2,has been carried out. This paper includes a description of traffic micro-simulation models forrural roads in general and a description of RuTSim model in particular. Common verificationtechniques of the simulation models are also discussed in this study.

    Based on the theoretical assessments, a model-to-model comparison verification scheme isselected to verify the RuTSim 2 model. That is, the model verification is performed by comparingthe simulation outputs from RuTSim 2 to the old version of RuTSim (RuTSim 1), since RuTSim1 is well verified and calibrated. Statistical hypothesis tests are used to check whether the meanand standard deviation differences of the simulation outputs between the two simulators aresignificant or not.

    Based on the verification results, the new version of the RuTSim model has comparable modelingof vehicle-vehicle and vehicle-infrastructure interactions as the old version. Furthermore, thehypothesis test results show that the differences of the mean simulation results of the twosimulators are not significant. Therefore, the new implementation of RuTSim model, RuTSim 2,has been proven to be equivalent model as the old version.

  • 23.
    Al Haji, Ghazwan
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Fowler, Scott
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Andersson Granberg, Tobias
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Smart traffic calming measures for smart cities - a pre-study2018Report (Other academic)
    Abstract [en]

    Traffic calming measures, such as speed bumps and elevated crossing points, are used to reduce speed, to prevent overtaking and generally contribute to a safer traffic situation. However, they might also cause increased response times for rescue vehicles (e.g. ambulances or fire trucks). An alternative to the conventional traffic calming measures is so-called smart traffic calming measures. These can determine when a vehicle approaches, whose journey should not be hindered, and adjust to allow for free passage for this vehicle.

    This report gives an overview of the problem, and some examples of smart  traffic calming measures are discussed. Special focus is put on the wireless communication necessary to detect emergency vehicles. Furthermore, existing challenges and possible solutions for traffic calming measures and the communication needed to make them smart are discussed.

  • 24. Al-ani, Neeran
    et al.
    Boutros, Mireille
    Linköping University.
    Flerpatientbesök – ett förbättringsförslag baserat på en analys av den dagligaverksamheten vid vårdcentralen Cityhälsan Söder: En kartläggning på Blodtrycksmottagning och Astma/KOL- mottagning med hjälp av Lean2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Östergötland County Council has begun to implement “Lean-Thinking" in healthcare service. Staff at healthcare service has experienced new challenges. Health care quality cannot anymore be measured only by medical treatment results, other factors are of importance, for example accessibility.

    The management of the health centre “Cityhälsan Söder” wished to identify problems that affect patient flow and requested proposals for improvements which could increase the number of patients cared for at Blood Pressure-department and Asthma/COL- department.

    For the mapping of the activities performed by a nurse during a working day, two data collection methods were used: observation and survey. Collected data were analysed in relation to the frame of reference concerning theories of Lean healthcare and logistics. Focus in the identification of problems was to improve the utilization of nursing time to allow more patient visits. 

    In the analysis eight types of wastes are especially used: overproduction, waiting, transportation, extra-processing, inventory, motion, defects and non-utilised skills. From the healthcare logistics point of view, the cancelations problem, lack of resources and matching capacity with demand was also analysed.

    To increase staff knowledge of how service may work better it was suggested to take advantage of the staff's creativity by expanding the personnel’s perception of patient flow in order to match capacity with demand. Other proposals concerned waiting-list management, which aims to introduce direct time booking of upcoming patient visits at both departments, freeing administrative time that can be spent to accommodate more patients. To standardize medical examinations on Asthma/COL-departments is also a proposal.

    IT-solutions for both departments may also create opportunities for more patient visits. A film that prepares the patient by teaching the correct blowing technique for the visit on Asthma/COL-department may accelerate medical examinations and free time that can be used better.

  • 25.
    Al-Dabbas, Khaled
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Analysis of GHG emissions reduction from road transport: a case study of the German passenger vehicles2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Transportation and energy play an essential role in modern society. Since the Industrial Revolution, fossil fuels have enabled great advancements in human society. Within this process, Internal Combustion Engines Vehicles (ICEVs) played a significant role in guaranteeing reliable and affordable long-distance transportation. However, the subsequent increase of the Motorized Private Transport resulted in undesired effects such as pollution. One instrument in reducing the Greenhouse Gas (GHG) emissions of the transport sector is to shift from the conventional ICEVs toward zero local emission vehicles. Electric Vehicles (EVs) are being promoted worldwide as a suitable powertrain technology that could replace the ICEVs. However, unless combined with electricity from renewable generation technologies the EVs will not effectively reduce GHG emissions. Through the simulation of future transport and energy sector scenarios in Germany, the GHG emission reductions have been analyzed. Techno-economic and environmental characteristics for several powertrain technologies under several vehicles charging strategies are evaluated. The thesis explores the impact of charging EVs on the electrical grid. The result show that EVs using smart charging strategies that support Vehicle-to-grid (V2G) are capable of fulfilling mobility needs of users while providing substantial flexibility to the electrical grid. Such flexibility can facilitate the future expansion of non-dispatchable Renewable Energy Sources (RES).

  • 26.
    Aldin, Niklas
    Linköping University, Department of Management and Engineering, Logistics Management. Linköping University, The Institute of Technology.
    The Luna Case within Bergman & Beving Tools: Changes in Logistics Management2002Report (Other academic)
    Abstract [en]

    Companies conducting business in multiple marketing channels need logistics and IT solutions that support their wide array of strategy and operations. Those, and other firms, do not solely rely on new concepts but also on continuously developing their businesses in the interaction between marketing and logistics. This case study will show on these aspects - how marketing and logistics may be integrated in such a channel environment by continuously developing the business as well as through new approaches in information technology - electronic commerce.

    The Luna case Within Bergman & Beving Tools illustrates the development of a medium sized distributor from catalogue based firm to flow co-ordinator in a group constellation, a change from a single steady going to a multiple requirement demanding marketing channel. Luna is a transaction intensive distributor of tools and machinery equipment with long experience in logistics and information technology. The company is guarantor for assortment quality, fast and reliable logistics through sophisticated IT solutions as well as value added competence in its trade relations with dealers and end customers. Independent dealers and end customers are found in Nordic industrial, construction, engineering, administration and consumer sectors. Bergman & Beving Tools is parent company to seven distributors of which Luna is the largest.

    To start with, this case describes the background development of the business in the fields of marketing, logistics and information technology until 1993. The second part between 1993 and 2001 describes how the marketing agenda has changed, how electronic commerce has been used to develop the business and changes in logistics, both on operational and strategic levels. As a whole the case describes changes in logistics management and how that has interacted with market development.

  • 27.
    Aldén, Anna
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Odebo, Stina
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    The use of ground equipment at airports2015Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    För att flygplatser ska kunna ha så hög kapacitet som möjligt krävs effektivisering av alla delar av flygplatsverksamheten. Denna studie har identifierat problem och utvecklingsområden av användningen av markutrustning på flygplatser. I studien har det även analyserats effektiviseringsmöjligheter. Några exempel på problem och utvecklingsområden som funnits är att utrustningen är utspridd på flygplatsen och att det finns för mycket utrustning. Ett av lösningsförslagen som föreslås i rapporten är att en tredjepartsaktör äger all markutrustning på flygplatsen och sedan bedriver uthyrning av utrustningen till användarna.

  • 28.
    Al-Egli, Asawar
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Al-Egli, Fadwa
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Kostnadsanalys och identifiering av logistikprocesser2018Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Majoriteten av företagen runt om i världen arbetar ständigt med att förbättra sin logistik. Detta eftersom om logistiken fungerar på ett bra sätt ger det upphov till ett bra flyt igenom hela processen samt bra produktresultat. Logistiken som används i dagsläget av olika byggföretag har i princip liknande grunder. Beroende på vad som skall göras kan processen skilja sig åt. Inom företaget NCC kan man hitta olika logistikprocesser som bygger på liknande förutsättningar. Varav en av logistikprocesserna ligger hos verksamheten Addera byggkoncept som arbetar utifrån ett industrialiserat koncept för renovering/stambyte av badrum i miljonprogrammets bostäder, med en mer standardiserad arbetsgång än ordinarie byggverksamhet. Denna specialanpassade logistikprocess kommer i denna studie jämföras med en mer traditionell logistikprocess för renovering/stambyte av badrum

  • 29.
    Alesand, Adam
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Kostnader vid reparation av vattenläckor i Linköpings kommun2013Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Water is an essential resource that we today take for granted. The distribution of drinking water is done with pipes in our water distribution network. These pipes have a limited lifetime and at some point they will rupture, with a leak as a result. The leak can lead to major consequences. Some examples are: disturbance in traffics, damage to property, as well as private individuals and businesses that are without water. Another consequence is the cost itself of repairing the leak, which sometimes is the most severe consequence.

    To avoid future problems with water leaks, it is important to renew the pipe network. The planning of this renewal is called renewal planning. A method in renewal planning is so-called “risk-based renewal planning”. This method aims to find the pipes that carry the highest risk. A pipe with high risk is a pipe that has high probability of rupturing, at the same time as the consequence of a rupture is great.

    Tekniska Verken in Linköping is in charge of the water distribution network in Linköping municipality. In their renewal planning they are working on a new tool, called “Knappen”. The ambition with “Knappen” is to be able to find pipes with high risk with “just one touch of a button”. “Knappen” is a calculation based on a variety of input data on probability and consequence. One of the factors to be used in the calculation is an estimate of the repair cost that the leak causes. This study has resulted in a formula for calculating this cost.

    The formula is based on data about past leaks from 2011. The factors that the formula turned out to depend on is: in which land type the leak has occurred, how far the distance is, which repair method has to be used and also the material and dimension of the pipe.

  • 30.
    Alfredsson, Nina
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Angvarson, Josefin
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    An analysis of the robustness of SAS crew schedules2015Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Scandinavian Airlines (SAS) är nordens största flygbolag och har en besättning på 5 000 personer med baser i Danmark, Norge och Sverige. SAS besättningsscheman för kabinpersonal med bas Stockholm samt piloter med samma bas och kvalifikationer för flygplanstypen Boeing 737 har analyserats. Genomförda förändringar efter att scheman publicerats under 2013 och 2014 har kartlagts. Förändringarna har utretts för att fastställa hur stor andel av ett schema som genomförs som planerat. Vidare har ett mätetal som även tar hänsyn till antalet ändringar som sker från planerad ledighet och sjukdom till någon form av produktion tagits fram, mätetalet kallas förändringskvot. Andelen avvecklat enligt plan och förändringskvoten är beräknade per produktionsdag. Mätetalens resultat är relativt jämna för 2013 och 2014. År 2013 avvecklades i genomsnitt 75 % av panerade produktionsdagar och förändringskvoten utgjorde i genomsnitt 30 %. Motsvarande siffror för år 2014 var 77 % och 29 %.

  • 31.
    Algmark, Carl
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Eskilsson, Mattias
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
    Omgivningspåverkan vid sänkhammarborrning2014Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Sänkhammarborrning är en metod som används för att utföra grundläggning med stålpålar. Metoden blir allt vanligare i Svenska tätbebyggda miljöer där krav ställs på låg omgivningspåverkan. Vid sänkhammarborrning borras ett foderrör av stål ner genom jordlagren till avsett djup, oftast till bärkraftigt berg. Foderröret lämnas sedan kvar, armeras, gjuts och utgör sedan själva pålen. Borrmaskinen består bland annat av en hammare som arbetar nere i hålet och drivs av antingen vatten eller luft. Borrföretagen har ofta tillgång till flera olika borrsystem men det saknas ibland underlag och forskning för hur olika borrsystem och metoder påverkar mark och omgivning vilket kan skapa en osäkerhet i projekteringsfasen och oförutsedda problem i utförandestadiet. Sänkhammarborrning anses ha en mindre massförträngande effekt men ger ändå en viss omgivningspåverkan både ovan och under mark. I den här studien har omgivningspåverkan under mark behandlats. Tre störningskällor har undersökts; vibrationer, uppspolning och trycksättning. Syftet har varit att teoretiskt undersöka hur vattendrivet- och luftdrivet sänkhammarborrsystem påverkar undergrunden i samband med att stålrörspålar installeras. För att nå syftet har en litteraturstudie och en intervjustudie genomförts. Även två fältbesök har gjorts. Litteratur och intervjuer har sedan analyserats med utgångspunkt i de tre nämnda fenomenen. Resultatet visar att de viktigaste faktorerna som påverkar hur stor omgivningspåverkan blir är markförutsättningar, maskinutrustning och utförandet. Vattendriven borrning visar sig löpa mindre risk att påverka omgivningen när det gäller uppspolning och trycksättning men om borrningen utförs på rätt sätt kan omgivningspåverkan undvikas även vid luftdriven borrning. De två borrsystemen har olika slagenergier och slagfrekvenser dock kan inga slutsatser dras av hur detta påverkar vibrationsnivåerna. Ett antal åtgärder finns för att minimera omgivningspåverkan, det handlar framförallt om att välja rätt borrsystem samt att borrningen utförs på rätt sätt.

  • 32.
    al-Haji, Ghazwan
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Integrated system for monitoring road safety performance in cities2014In: Urban street design & planning / [ed] Pratelli, A, WIT Press, 2014, p. 105-114Chapter in book (Refereed)
    Abstract [en]

    A strong monitoring system of road safety in a city is necessary to ensure that the strategies implemented will meet stated targets at city and national levels. Although road safety performance is a result of many key indicators, only a few of these indicators are generally considered in monitoring the performance of road safety in a city and in comparison to other cities. A number of monitoring systems are already being developed and used in road safety and they range from relatively simple models to highly complex ones depending on the number of indicators involved, details of data and complexity of methods used in calculations and analysis. In road safety, there are three main types of monitoring that are generally used, which are: Process Monitoring, Outcome Monitoring and Target Monitoring. The aim of this paper is to provide the importance and usefulness of having a fourth type of monitoring, so-called Integrated Monitoring, that links process, outcome and targets together. The paper also provides a conceptual overview, and illustrations that are used in the construction of the integrated monitoring system.

  • 33.
    Al-Haji, Ghazwan
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Road Safety Development Index: Theory, Philosophy and Practice2007Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This dissertation develops, presents and tests a new international tool, the so-called Road Safety Development Index (RSDI), which indicates in a comprehensive and easy way the severity of the road safety situation in a specific country and/or in comparison with other countries. There are three pillars of outcomes involved in the framework of RSDI. One pillar is the People focus (road user behaviour). The second is the System focus (safer vehicles, safer roads, enforcement, management, etc). The third is the Product focus in terms of accident death rates. This thesis analyses each of these pillars. In addition, RSDI links the key national practices of road safety to each other and to the end-results (accident death rates). The study suggests a master-list of performance indicators to be implemented for assessing road safety level in a country and for RSDI building. Based on the “master-list”, a short key list of performance indicators is chosen and classified into two primary categories that correspond to two groups of countries: LMCs “Less Motorised Countries” and HMCs “Highly Motorised Countries”. RSDI aggregates the key performance indicators into one single quantitative value (composite index). Four main objective and subjective approaches are used to calculate RSDI and determine which one is the best. One approach uses equal weights for all indicators and countries, whereas the other approaches give different weights depending on the importance of indicators. Two empirical studies were carried out, in different parts of the world, to determine the applicability of this tool in real world applications. The first empirical study comes from eight European countries (HMCs). The second empirical study comes from five Southeast Asian countries (LMCs). The RSDI results from this study indicate a remarkable difference between the selected countries even at the same level of motorisation and/or with close accident death rates. The unavailability of comparable and useful data are problems for deeper analysis of RSDI, especially the index should be as relevant as possible for different parts of the world. The empirical and theoretical assessments prove that RSDI can give a broader picture of the whole road safety situation in a country compared to the traditional models and can offer a simple and easily understandable tool to national policy makers and public.

  • 34.
    Alho, Yasser
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Usef Eillas, Rostam
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Learning time for graduated project manager2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Byggbranschen står idag inför stora utmaningar gällande rekrytering av erfarna projektledare. Företagen har upplevt svårigheter med att hitta erfarna projektledare, detta beror på att det saknas nästan två generationer av projektledare samt att många går i pension. En lösning till problemet är att anställa nyexaminerade projektledare för att fylla luckan. Problemet med nyutexaminerade är att de saknar erfarenhet när de kommer ut i arbetslivet. Det är en utmaning för konsultföretagen, eftersom inlärningstiden för att bli projektledare vanligtvis är långa perioder.

    Syftet med denna studie är att förtydliga inlärningstiden för de nyutexaminerade projektledare samt att ge organisationen ett underlag för att de ska kunna se vad de bör skapa för förutsättningar och metoder. Huvudfrågorna som behandlas i vår studie är ”Vad innebär det att vara projektledare?” och ”Vad krävs för att man skall gå från att vara en nyutexaminerade byggingenjör till att bli projektledare?”

    Undersökningen är en kvalitativ studie som genomförts på WSP Management Östergötland. Den empiriska datainsamlingen har skett via personliga intervjuer med elva respondenter fördelade på Norrköping och Linköping kontoren.

    Studien visar på att vara projektledare kan variera mycket beroende på hur man väljer att tolka det, men inom byggbranschen handlar det om att leverera en produkt eller ett resultat till en begränsad budget och till en bestämd tid. Som projektledare är man beställarens ”högra hand” och ska uppfylla kundens önskemål i projektet. För att detta ska gå ihop krävs ständig kommunikation så att man förstår varandra och undviker missförstånd.

    Med utgångspunkt från undersökningen har vi även konstaterat att det som krävs för att man ska gå från att vara nyexaminerad byggingenjör till att bli projektledare inom området management, är rätt metod, rätt organisatoriska- och individuella förutsättningar samt att man övervinner krav och hinder som ställs från beställarsidan.

  • 35.
    Allert, Eric
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Dalgren, Carl
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Introduction of newly qualified structural engineers in small construction companies2015Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Byggbranschen präglas framöver av stora pensionsavgångar vilket kommer kräva rekryteringen av ny arbetskraft. Många av de rutinerade tjänstemännen handplockas till de stora konsultföretagen där arbetsvillkoren och förmånerna i vissa fall upplevs bättre än hos entreprenadföretagen. Därför måste de mindre entreprenadföretagen anställa nyexaminerade byggnadsingenjörer i allt större utsträckning. Introduktionsprocessen för en nyanställd, och i synnerhet en nyexaminerad tjänsteman kan ta lång tid och ta upp resurser som mindre företag inte alltid kan avvara. Denna studie syftar därför till att försöka hitta faktorer och tips som leder till en lyckad introduktion gällande första arbetsuppgifter, socialisation och motivation för bibehållandet av arbetskraft. Denna studie är baserad på teori kring ämnet som sedan backats upp av empiri i form av sammanlagt åtta intervjuer av tjänstemän på företagen, Byggentreprenören AB och Stångebro Bygg AB.

  • 36.
    Allström, Andreas
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Highway Traffic State Estimation and Short-term Prediction2016Licentiate thesis, monograph (Other academic)
    Abstract [en]

    Traffic congestion is increasing in almost all large cities, leading to a number of negative effects such as pollution and delays. However, building new roads is not a feasible solution. Instead, the use of the existing road network has to be optimized, together with a shift towards more sustainable transport modes. In order to achieve this there are several challenges that needs to be addressed. One challenge is the ability to provide accurate information about the current and future traffic state. This information is an essential input to the traffic management center and can be used to influence the choices made by the travelers. Accurate information about the traffic state on highways, where the potential to manage and control the traffic in general is very high, would be of great significance for the traffic managers. It would help the traffic managers to take action before the system reaches congestion and limit the effects of it. At the same time, the collection of traffic data is slowly shifting from fixed sensors to more probe based data collection. This requires an adaptation and further development of the traditional traffic models in order for them to handle and take advantage of the characteristics of all types of data, not just data from the traditionally used fixed sensors.

    The objective of this thesis is to contribute to the development and implementation of a model for estimation and prediction of the current and future traffic state and to facilitate an adaptation of the model to the conditions of the highway in Stockholm. The model used is a version of the Cell Transmission Model (CTM-v) where the velocity is used as the state variable. Thus, together with an Ensemble Kalman Filter (EnKF) it can be used to fuse different types of point speed measurements. The model is developed to run in real-time for a large network. Furthermore, a two-stage process used to calibrate the model is implemented. The results from the calibration and validation show that once the model is calibrated, the estimated travel times corresponds well with the ground truth travel times collected from Bluetooth sensors.

    In order to produce accurate short-term predictions for various networks and conditions it is vital to combine different methods. We have implemented and evaluated a hybrid prediction approach that assimilates parametric and non-parametric short-term traffic state prediction. To predict mainline sensor data we use a neural network, while the CTM-v is ran forward in time in order to predict future traffic states. The results show that both the hybrid approach and the CTM-v prediction without the additional predicted mainline sensor data is superior to a naïve prediction method for longer prediction horizons.

  • 37.
    Allström, Andreas
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Archer, Jeffery
    Sweco Infrastructure, Sweden.
    Bayen, Alexandre
    University of California, Berkeley, USA.
    Blandin, Sebastian
    University of California, Berkeley, USA.
    Butler, Joe
    California Center for Innovative Transportation. USA.
    Gundlegård, David
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Koutsopoulose, Haris N
    Royal Institute of Technology (KTH), Sweden.
    Lundgren, Jan
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Rahmani, Mahmood
    Royal Institute of Technology (KTH), Sweden.
    Tossavainen, Olli-Pekka
    NAVTEQ LLC, USA.
    Mobile Millennium Stockholm2011In: 2nd International Conference on Models and Technologies for Intelligent Transportation Systems, 2011Conference paper (Other academic)
  • 38.
    Allström, Andreas
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Barceló, Jaume
    Department of Statistics and Operations Research, Universitat Politècnica de Catalunya.
    Ekström, Joakim
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Grumert, Ellen
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Gundlegård, David
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Rydergren, Clas
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Traffic management for smart cities2017In: Designing, developing, and facilitating smart cities: urban design to IoT solutions. Part III / [ed] Vangelis Angelakis, Elias Tragos, Henrich C. Pöhls, Adam Kapovits and Alessandro Bassi, Switzerland: Springer, 2017, 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.

  • 39.
    Allström, Andreas
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology. Sweco TransportSystem, Stockholm, Sweden.
    Bayen, Alexandre M.
    University of California Berkeley, USA.
    Fransson, Magnus
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology. Sweco TransportSystem, Stockholm, Sweden.
    Gundlegård, David
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Patire, Anthony D.
    University of California Berkeley, USA.
    Rydergren, Clas
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Sandin, Mats
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Calibration Framework based on Bluetooth Sensors for Traffic State Estimation Using a Velocity based Cell Transmission Model2014In: Transportation Research Procedia, ISSN 2352-1465, Vol. 3, p. 972-981Article in journal (Refereed)
    Abstract [en]

    The velocity based cell transmission model (CTM-v) is a discrete time dynamical model that mimics the evolution of the traffic velocity field on highways. In this paper the CTM-v model is used together with an ensemble Kalman filter (EnKF) for the purpose of velocity sensor data assimilation. We present a calibration framework for the CTM-v and EnKF. The framework consists of two separate phases. The first phase is the calibration of the parameters of the fundamental diagram and the second phase is the calibration of demand and filter parameters. Results from the calibrated model are presented for a highway stretch north of Stockholm, Sweden.

  • 40.
    Allström, Andreas
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Ekström, Joakim
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Gundlegård, David
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Ringdahl, Rasmus
    Linköping University, Department of Science and Technology, Communications and Transport Systems.
    Rydergren, Clas
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Bayen, Alexandre M.
    Department of Civil and Environmental Engineering, University of California.
    Patire, Anthony D.
    Department of Civil and Environmental Engineering, University of California.
    A hybrid approach for short-term traffic state and travel time prediction on highways2016In: TRB 95th annual meeting compendium of papers, 2016Conference paper (Refereed)
    Abstract [en]

    Traffic management and traffic information are essential in urban areas, and require a good knowledge about both the current and the future traffic state. Both parametric and non-parametric traffic state prediction techniques have previously been developed, with different advantages and shortcomings. While non-parametric prediction has shown good results for predicting the traffic state during recurrent traffic conditions, parametric traffic state prediction can be used during non-recurring traffic conditions such as incidents and events. Hybrid approaches, combining the two prediction paradigms have previously been proposed by using non-parametric methods for predicting boundary conditions used in a parametric method. In this paper we instead combine parametric and non-parametric traffic state prediction techniques through assimilation in an Ensemble Kalman filter. As non-parametric prediction method a neural network method is adopted, and the parametric prediction is carried out using a cell transmission model with velocity as state. The results show that our hybrid approach can improve travel time prediction of journeys planned to commence 15 to 30 minutes into the future, using a prediction horizon of up to 50 minutes ahead in time to allow the journey to be completed.

  • 41.
    Allström, Andreas
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Ekström, Joakim
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Gundlegård, David
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Ringdahl, Rasmus
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Rydergren, Clas
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Bayen, Alexandre M.
    Department of Civil and Environmental Engineering, University of California, Berkeley, CA, USA.
    Patire, Anthony D.
    Department of Civil and Environmental Engineering, University of California, Berkeley, CA, USA.
    Hybrid Approach for Short-Term Traffic State and Travel Time Prediction on Highways2016In: Transportation Research Record, ISSN 0361-1981, E-ISSN 2169-4052, Vol. 2554, p. 60-68Article in journal (Refereed)
    Abstract [en]

    Traffic management and traffic information are essential in urban areas and require reliable knowledge about the current and future traffic state. Parametric and nonparametric traffic state prediction techniques have previously been developed with different advantages and shortcomings. While nonparametric prediction has shown good results for predicting the traffic state during recurrent traffic conditions, parametric traffic state prediction can be used during nonrecurring traffic conditions, such as incidents and events. Hybrid approaches have previously been proposed; these approaches combine the two prediction paradigms by using nonparametric methods for predicting boundary conditions used in a parametric method. In this paper, parametric and nonparametric traffic state prediction techniques are instead combined through assimilation in an ensemble Kalman filter. For nonparametric prediction, a neural network method is adopted; the parametric prediction is carried out with a cell transmission model with velocity as state. The results show that the hybrid approach can improve travel time prediction of journeys planned to commence 15 to 30 min into the future, with a prediction horizon of up to 50 min ahead in time to allow the journey to be completed

  • 42.
    Allström, Andreas
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Gundlegård, David
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Rydergren, Clas
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Evaluation of travel time estimation based on LWR-v and CTM-v: A case study in Stockholm2012In: 15th International IEEE Conference on Intelligent Transportation Systems (ITSC), 2012, Piscataway, N.J, USA: IEEE , 2012, p. 1644-1649Conference paper (Refereed)
    Abstract [en]

    Real-time estimations of current and future traffic states are an essential part of traffic management and traffic information systems. Within the Mobile Millennium project considerable effort has been invested in the research and development of a real-time estimation system that can fuse several sources of data collected in California. During the past year this system has been adapted to also handle traffic data collected in Stockholm. This paper provides an overview of the model used for highways and presents results from an initial evaluation of the system. As part of the evaluation process, GPS data collected in an earlier field-test and estimations generated by the existing system used by the TMC in Stockholm, are compared with the estimations generated by the Mobile Millennium system. Given that the Mobile Millennium Stockholm system has not undergone any calibration, the results from the evaluation are considered promising. The estimated travel times correspond well to those measured in the field test. Furthermore, the estimations generated by the Mobile Millennium system can be regarded as superior to those of existing traffic management system in Stockholm. The highway model was found to perform well even with a reduction in the number of sensors providing data. The findings of this study indicate the robustness of the Mobile Millennium system and demonstrate how the system can be migrated to other geographical areas with similar sources of available data.

  • 43.
    Alm, Johanna
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Plantin Vantell, My
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Problems and potential improvements of the order- and delivery process at Region Östergötland2015Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Region Östergötland (RÖ) har många olika order- och leveransprocesser varav en kallas för den yttre order- och leveransprocessen. Denna process är det informations- och materialflöde där beställning går direkt till leverantör och inte via den centraldepå som finns. Det är många personer som är inblandade och som ansvarar för olika delar av den yttre order- och leveransprocessen, samtidigt som personerna i fråga även arbetar på olika avdelningar. Detta tillsammans med att delar av processen sköts av en extern aktör har lett till att ingen ansvarar för hela processen i sig, och således finns inte heller en sammanhållen bild över processen. Syftet med rapporten är att ge en sammanhållen bild av den yttre order- och leveransprocessen samt belysa eventuella problem och ge förslag på förändringar som kan förbättra processen.

  • 44.
    Altkvist, Therese
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Hultman, Hanna
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Godsspårningssystem för landstinget i Östergötland2014Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Landstinget i Östergötland efterfrågar en högre spårbarhet för läkemedel och övrigt gods. Idag används godsspårningssystemet Arrival, levererat av Pitney Bowes för godsmottagningarna på Universitetssjukhuset i Linköping, Vrinnevisjukhuset i Norrköping samt på Lasarettet i Motala. För att kunna rekommendera vad Landstinget i Östergötland bör tänka på vid upphandling av ett eventuellt nytt godsspårningssystem har deras nuvarande system utvärderats och en omvärldsbevakning av alternativa spårningssystem har genomförts. Studien av Arrival baserades på fältstudier som genomfördes på godsmottagningar på Universitetssjukhuset i Linköping och Lasarettet i Motala samt genom intervjuer med användare och en kunnig brukare av systemet. Denna utvärdering av systemet resulterade i att ett antal förbättringsområden identifierades. I omvärldsbevakningen undersöktes tre alternativa godsspårningssystem från tre olika leverantörer. Ett nyutvecklat godsspårningssystem av ISS, TrueMobile Track and Trace av Optidev samt SendSuite av Pitney Bowes. Resultatet av detta examensarbete är ett antal rekommendationer till Landstinget i Östergötland avseende spårning av gods. Landstinget bör inkludera åsikter från systemanvändare vid upphandling samt erbjuda dem en fullgod utbildning i det initierande stadiet av en eventuell implementering av ett nytt godsspårningssystem. Landstinget bör vidare efterfråga funktioner som avläsningsverktyg som kan synkronisera trådlöst och en funktion för en mer tidseffektiv leverans av flera paket samt se över möjligheterna med RFID.

  • 45.
    Alyusif, Natalee
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Yacoub, Sally
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Cost comparison of alternative foundation methods2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    SAMMANFATTNING Syftet med detta projekt är att jämföra byggnaders olika grundläggningsmetoder, vid grundläggning på jordar med låg hållfasthet, för att kunna välja den mest ekonomiska metoden. I detta examensarbete har fokus lagts på fyra grundläggningsmetoder vilka är betongpålar, Kalkcement-pelare (KC-pelare), träpålar och stenpelare och deras respektive kostnadseffektivitet. Analysen baseras på utredning av hur företagets tid och kostnad påverkas i början av varje projekt samt vid användning av de olika grundläggningsmetoderna med fokus på olika faktorer som kan påverka valet av grundläggningsmetoder. Denna undersökning genomfördes genom att studera fyra projekt som utfördes av NCC anläggning och deras dotterföretag Hercules: tre av projekten är grundlagda med betongpålar och ett av projekten är grundlagt med stenpelare. Beräkningar innefattar projekteringskostnader och kostnad för utförande av de olika metoder där prisdokument fåtts av NCC anläggning och Hercules. Ett frågeformulär har skickats till två produktionschefer och en platschef som har arbetat med de olika metoderna för att få mer information från produktion. Dessutom samlades information från olika litteratur och hemsidor sökning för att förstå olika egenskaper hos varje metod Slutsatsen av detta arbete ät att den mest ekonomiska grundläggningsmetoden är betongpålar samt den är mest användbara hos NCC, medan stenpelare är den dyraste metoden som har använts bara en gång av NCC anläggning. Dessutom fick vi antagande projekt om KC-pelare som visas vara dyrt metod jämförd med betongpålar. Därtill har inte fått något projekt om träpålar, därför är det svårt att undersöka den metoden.

  • 46.
    Anany, Hossam
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Effectiveness of a speed advisory traffic signal system for Conventional and Automated vehicles in a smart city2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis project presents a traffic micro simulation study that investigates the state-of-the-art in traffic management "Green Light Optimal Speed Advisory (GLOSA)" for vehicles in a smart city. GLOSA utilizes infrastructure and vehicles communication through using current signal plan settings and updated vehicular information in order to influence the intersection approach speeds. The project involves simulations for a mixed traffic environment of conventional and automated vehicles both connected to the intersection control and guided by a speed advisory traffic management system. Among the project goals is to assess the effects on traffic performance when human drivers comply to the speed advice. The GLOSA management approach is also accessed for its potential to improve traffic efficiency in a full market penetration of connected automated vehicles with enhanced capabilities such as having shorter time head ways.

  • 47.
    Anany, Hossam
    Linköping University, Department of Science and Technology, Communications and Transport Systems.
    Effectiveness of a Speed Advisory Traffic Signal System for Conventional and Automated vehicles in a Smart City2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis project investigates the state-of-the-art in traffic management "Green Light Optimal Speed Advisory (GLOSA)" for vehicles in a smart city. GLOSA utilizes infrastructure and vehicles communication through using current signal plan settings and updated vehicular information in order to influence the intersection approach speeds.

    The project involves traffic microscopic simulations for a mixed traffic environment of conventional and automated vehicles (AVs) both connected to the intersection control and guided by a speed advisory traffic management system. Among the project goals is to assess the effects on traffic performance when human drivers comply to the speed advice. The GLOSA management approach is accessed for its potential to improve traffic efficiency in a full market penetration of connected AVs with absolute compliance. The project also aims to determine the possible outcome resulting from enhancing the AVs capabilities such as implementing short time headways between vehicles in the future. 

    The best traffic performance results achieved by operating GLOSA goes for connected AVs with the lowest simulated time headway (0.3 sec). The waiting time reduction reaches 95% and trip delay lessens to 88 %.

  • 48.
    Andersson, Anja
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    Logistic process models for Swedtrac2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Detta examensarbete har utförts hos Swedtrac Trafik AB som är ett dotterbolag till Swedtrac AB. Swedtrac Trafik AB har trafikutövartillstånd och erbjuder utbildningar inom alla trafiksäkerhetsrelaterade delar av järnvägsverksamheten. Företaget har också verksamhet som löser kundernas transportbehov. Swedtrac Trafik AB baserar sin verksamhetsutveckling på processer vilket innebär att en processorienterad verksamhetsstyrning behövs för att klara dagens allt intensivare konkurrens på en global marknad. Därför är en initial processmall nödvändig. Syftet med detta examensarbete är att kartlägga nuvarande processer och göra en processmall/ett flödesschema från kundbeställning till slutprodukt samt ge en klar bild över var i processerna det finns möjlighet till effektivisering. Detta arbete är en studie av företagets processer med utvald processkartläggningsmetod. I metoden ingår studiebesök, telefon- grupp- och personlig intervju. Resultatet från dessa sammanställningar ger en djupare insyn i den nuvarande processen. Vid processkart-läggningen utgår arbetet från två vinklar: den ena är en ”as-is” process (swim lane chart) som utifrån beskrivningar från avdelningarnas intervjuer har ritats upp ett flöde över nuläget. Den andra är en ”to-be” process där problem som hittas i nulägesflödet har getts förslag på åtgärder. Processkarläggningen bygger på en SS-modell(sjustegsmodell). Varje steg bidrar till processmallen och har sitt eget syfte, mål och ett centralt värde för processkartläggningen. Resultatet består av två processmallar samt förbättringsförslag för nuläget och för framtiden. Förbättringsförslagen baseras på en processanalys av ”as-is” och ”to-be” processen. Processmallarna konstrueras med hjälp av modelleringsspråket ”BPMN”. Genom att jämföra de två processerna kan problem och förbättringsmöjligheter identifieras. När onödiga aktiviteter eliminerats och icke värdeskapande aktiviteter ändrats till värdeskapande, leder det till en minskning av administrativa kostnader samt att processens förmåga och effektiviteter förbättras. Detta innebär att processen kommer att utvecklas till en mer värdeskapande process.

  • 49.
    Andersson, Anna
    et al.
    Linköping University, Department of Thematic Studies, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    Harir, Mourad
    Helmholtz Zentrum München, Germany.
    Gonsior, Michael
    University of Maryland Center for Environmental Science, USA.
    Hertkorn, Norbert
    Helmholtz Zentrum München, Germany.
    Schmitt-Kopplin, Philippe
    Helmholtz Zentrum München, Germany.
    Kylin, Henrik
    Linköping University, Department of Thematic Studies, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    Karlsson, Susanne
    Linköping University, Department of Thematic Studies, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    Ashiq, Muhammad Jamshaid
    Linköping University, Department of Thematic Studies, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    Lavonen, Elin
    Norrvatten, Kvalitet och Utveckling.
    Nilsson, Kerstin
    VA SYD.
    Pettersson, Ämma
    Nodra.
    Stavklint, Helena
    Tekniska verken i Linköping.
    Bastviken, David
    Linköping University, Department of Thematic Studies, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    Waterworks-specific composition of drinking water disinfection by-products2019In: Environmental Science: Water Research & Technology, ISSN 2053-1419, no 5, p. 861-872Article in journal (Refereed)
    Abstract [en]

    Reactions between chemical disinfectants and natural organic matter (NOM) upon drinking water treatment result in formation of potentially harmful disinfection by-products (DBPs). The diversity of DBPs formed is high and a large portion remains unknown. Previous studies have shown that non-volatile DBPs are important, as much of the total toxicity from DBPs has been related to this fraction. To further understand the composition and variation of DBPs associated with this fraction, non-target analysis with ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) was employed to detect DBPs at four Swedish waterworks using different types of raw water and treatments. Samples were collected five times covering a full year. A common group of DBPs formed at all four waterworks was detected, suggesting a similar pool of DBP precursors in all raw waters that might be related to phenolic moieties. However, the largest proportion (64–92%) of the assigned chlorinated and brominated molecular formulae were unique, i.e. were solely found in one of the four waterworks. In contrast, the compositional variations of NOM in the raw waters and samples collected prior to chemical disinfection were rather limited.This indicated that waterworks-specific DBPs presumably originated from matrix effects at the point of disinfection, primarily explained by differences in bromide levels, disinfectants (chlorine versus chloramine) and different relative abundances of isomers among the NOM compositions studied. The large variation of observed DBPs in the toxicologically relevant non-volatile fraction indicates that non-targeted monitoring strategies might be valuable to ensure relevant DBP monitoring in the future.

  • 50.
    Andersson, Emma
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    An Economic Evaluation of the Swedish Prioritisation Rule for Conflict Resolution in Train Traffic Management2014In: Procedia - Social and Behavioral Sciences: Transportation: Can we do more with less resources?, Elsevier, 2014, p. 634-644Conference paper (Refereed)
    Abstract [en]

    An increase in train traffic is a politically welcomed trend, which on the other hand has led to too high capacity utilisation at times and a railway network sensitive to disturbances. Delays are easily spread, causing high cost. A mean of controlling the secondary delays is to use efficient operational prioritisation rules for trains in conflict. This paper presents an evaluation of the current Swedish prioritisation rule. For two frequent conflict situations the associated cost related to applying the rule is calculated. The result indicates a poor economic efficiency and show that significant savings can be achieved by changing strategy.

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