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The purpose of this thesis is to compare how the mathematics departments at Uppsala University and Alvar Aalto University relate to and manage their collections of mathematical models. In the thesis the importance of individuals in relation to this type cultural heritage and the situation for university collections will be discussed. Therefore the individuals’ interpretations of the approach are a major part of the study. Questions regarding the collections condition, placement, role, the knowledge about them and the responsibility for them are discussed and analysed. The methods used in the study were qualitative and taped interviews were done with three informants. The method of observation was also used to study the condition and placement of the collections and data was also collected from e-mail and conversations. The theories chosen for this study are phenomenology, cultural heritage and ideas of objects containing social ideas. The result from the study shows that the universities relate to and manage their collections differently. The collection at Aalto University has been cared for, been made available and used in teaching, which has resulted in that the awareness of it is high. At Uppsala University the majority of the collection is in poor condition and it is almost considered forgotten by the department. A few of the objects have been used in teaching. The collection has not been made available to students or employees. The study has also found that university collections could be considered museum objects as well tools for teaching and research. Universities are not museums, their main goal is not to care for huge collections and this affects their values and the management of them. Individuals have a significant impact on how university collections are managed and made available although this varies depending on the responsibility taken by the department itself. If the individuals’ knowledge about the collections is recorded, the collections are managed better.

The teaching of rational numbers to young students (grade 4-6) is known to be difficult. It is for instance difficult for students to understand that fractions and decimal numbers may represent the same value, or that fraction has a specific place on the number line, i.e. that it is a number among other numbers. The purpose of this article is to discuss and exemplify how students can be involved in a theoretical exploration of fractions as numbers. The basis of the students’ exploration was a designed situation where they were to make measurements of wooden rods where the measurements did not make an equal, i.e. “a little bit” was missing. With these measurements students in joint discussions were able to design a general model for fractions. Such a model could be used as a tool in discussions of “the whole” and “its parts” in fractions. The article is based on data from a series of Learning studies conducted in a grade 4 in an intercultural school in 2012-2013. Undervisning om rationella tal på mellanstadiet är ett erkänt svårt område. Eleverna har till exempel svårt att förstå att tal i bråkform och decimaltal kan representera samma värde eller att tal i bråkform har en bestämd plats på tallinjen, det vill säga att de är tal. I den här artikeln diskuteras och exemplifieras hur elever kan engageras i ett teoretiskt utforskande av tal i blandad form. Grunden för elevernas utforskande bestod i situationer där eleverna fick göra jämförelser av trästavar som inte gick jämt upp - det saknades ”en liten bit”. Utifrån dessa jämförelser kunde eleverna i gemensamma diskussioner skapa en generell modell för tal i blandad form, det vill säga en modell som också kunde beskriva mätningar som inte gick jämnt upp. Analysen visar bland annat att arbetet med modellen gjorde det möjligt för eleverna att diskutera heltalsdelar i förhållande till bråkdelar i tal i blandad form. Artikeln bygger på data från en serie Learning studies som genomfördes i en årskurs 4 på en interkulturell skola under 2012 – 2013.

The roads in our society are in a state of constant degradation. The reasons for this are many, and therefore constructed to have a certain lifetime before being reconstructed. To minimize the cost of maintaining the important transport road network high quality prediction models are needed. This report presents new models for flexible pavement structures for initiation and propagation of fatigue cracks in the bound layers and rutting for the whole structure. The models are based on observations from the Swedish Long Term Pavement Performance (LTPP) database. The intention is to use them for planning maintenance as part of a pavement management system (PMS). A statistical approach is used for the modeling, where both cracking and rutting are related to traffic data, climate conditions, and the subgrade characteristics as well as the pavement structure. QC 20130325

This book presents some recent systems engineering and mathematical tools for health care along with their real-world applications by health care practitioners and engineers. Advanced approaches, tools, and algorithms used in operating room scheduling and patient flow are covered. State-of-the-art results from applications of data mining, business process modeling, and simulation in healthcare, together with optimization methods, form the core of the volume. Systems Analysis Tools for Better Health Care Delivery illustrates the increased need of partnership between engineers and health care professionals. This book will benefit researchers and practitioners in health care delivery institutions, staff members and professionals of specialized hospital units, and lecturers and graduate students in engineering, applied mathematics, business administration and health care.

Bruk av salt på vinterveger er et viktig virkemiddel for å oppnå best mulig sikkerhet og framkommelighet på vinteren, samtidig som salting kan ha negative effekter på miljø, biler og vegutstyr. Veg- og trafikkmyndighetene i de nordiske landene har derfor et behov for å optimalisere saltbruken ved å holde et lavest mulig saltforbruk men fortsatt kunne nå målene med hensyn på framkommelighet og trafikksikkerhet. Et tiltak for å kunne optimalisere saltbruken er å utvikle et operasjonelt verktøy som kan forutsi varigheten av et salttiltak under ulike vegforhold. En kan dermed unngå unødvendig salttiltak og redusere risikoen for glatt veg på grunn av for lite salt. NordFoU-prosjektet Modelling Residual Salt (MORS) har som mål å utvikle en modell for utviklingen av restsaltmengde under ulike forhold. Danmark, Sverige, Island og Norge har deltatt i prosjektet. For å kunne følge restsaltutviklingen under kontrollerte forhold har det blitt gjennomført feltforsøk på en testbane ved Bygholm, Horsens (Danmark). På en lukket bane har blitt gjennomført salttiltak og deretter målt restsaltutviklingen og sentrale parametere med og uten trafikk. Målingene har skjedd med både manuelle målemetoder og automatiske målinger (Vaisala Rosa-system). Ved gjennomføringen av feltforsøkene har prosjektet møtt noen utfordringer. Det opprinnelige asfaltdekket på testbane var ujevnt, hadde mye sprekkdannelser og manglet tverrfall. Banen måtte derfor reasfalteres. Etter reasfaltering har det vist seg at teksturen på vegoverflaten er for lav til at prosjektet kan være sikre på at resultatene er fullt ut representerbare for ordinære veger. Ut fra feltforsøkene ble det også oppdaget installeringen av vegbanesensorene var helt avgjørende for målekvaliteten. Etter andre feltforsøk måtte derfor en del av vegbanesensorene reinstalleres. Utfordringene knyttet til gjennomføringen av feltforsøkene har gjort at prosjektet ikke har kunnet nå alle må slik opprinnelig skrevet i prosjektplanen. Hvordan restsaltmengden utvikler seg ette et salttiltak vil påvirkes av mange prosesser. For å få en oversikt over de antatte prosesser og parametere bak disse er det blitt prinsipiell massebalansemodell. I alt ni prosesser er blitt identifisert og bak disse en rekke faktorer. For videre modellutvikling en forenkling har vært nødvendig. Ut fra feltforsøkene har det blitt konkludert med at det er to prosesser som er svært viktige for restsaltutviklingen; avrenning og «splash og spray» (sprut pga. trafikk). Modellen som har blitt utviklet basert på innsamlet data tar for seg disse to prosessene.

Detta VTI notat presenterar en beräkningsmetod för beräkning av förväntad kölängd och restidsfördröjning för enfältiga vägavsnitt utan omkörningsmöjligheter. Metoden utvecklades 2001 och presenterades i ett PM. Bakgrunden till modellutvecklingen var att dåvarande Vägverket (nu Trafikverket) planerade att införa så kallade 1+1-vägar, det vill säga, vägar med längre delsträckor utan omkörningsmöjlighet. Den utvecklade beräkningsmetoden har sedermera visat sig värdefull även vid framkomlighetsberäkningar för 2+1-vägar med varierande andel tvåfältsavsnitt och har använts vid framtagning av hastighetsflödessamband till Trafikverkets ”Effektsamband för vägtransportsystemet”. Metoden använder avsnittslängd, trafikflöde samt medelhastighet och standardavvikelse som indata. Metoden är uppdelad på beräkning av effekter på grund av enstaka långsamtgående fordon samt effekter vid ”normal” hastighetsfördelning. Då mätdata saknades vid modellutvecklingen jämfördes metoden med simuleringskörningar med den mikroskopiska trafiksimuleringsmodellen AIMSUN. Resultaten visar på en relativt god korrelation men generellt så ger den analytiska metoden cirka 1,2 procent lägre restidsfördröjning. En stor del av skillnaden mellan modellerna vid måttliga flöden bör kunna härledas till det stokastiska inslaget i simuleringen. Det bör även påpekas att varken den analytiska modellen eller trafiksimuleringsmodellen har kalibrerats och validerats mot verkliga data för denna typ av väg. Skillnaden mellan modellerna innebär således inte att den analytiska modellen självklart är den som avviker från verkligheten. This VTI report presents a method for calculating expected queue length and travel time delay on one lane road sections without overtaking possibilities. The method was developed 2001 and presented in a working paper. The background for the model development was that the Swedish Road Administration (now the Swedish Transport Administration) planned to build so called 1+1 roads, i.e. roads with longer sections without overtaking possibilities. The method developed has later on also shown to be valuable for level of service calculations of 2+1 roads with varying share of two lane sections and for developing speed-flow relationships for the Administration’s ”Effect calculations for road facilities”. The method uses section length, traffic flow, average speed and standard deviation as input. The method is divided with respect to calculation of effects due to single slowrunning vehicles and effects at “normal” speed distribution. Since no data were available when the model was developed, the model results were instead compared to traffic simulations with the microscopic traffic simulation model AIMSUN. The results show a good correlation but the analytical model gives in general approximately 1.2 per cent lower travel time delay. The differences can probably partly be explained by the stochastic parts of the simulation model. One should also remember that neither the analytical model nor the simulation model has been calibrated and validated with real data for this type of roads. Thus, the differences between the models do not necessary imply that the analytical model is the one deviating from reality.

Det första järnvägspaketet har omarbetats i den europeiska unionen och fastsällt en nytt direktiv, där banavgifter utgör en del. Samtidigt arbetar Trafikverket samtidigt med frågor om marginalkostnadsbaserade avgifter, finansierande avgifter och tilldelning av knapp bankapacitet. Den europeiska unionens direktiv ger inga tydliga riktlinjer för hur marginalkostnadsbaserade avgifter ska beräknas, speciellt beträffande kapacitetsbrist. Både EU: s direktiv och Trafikverket ignorerar väsentliga externa effekter som borde spela stor roll för fastställande av samhällsekonomiskt effektiva avgifter. Inledningsvis beskrivs kort hur EU: s direktiv ser på banavgifter samt några av Trafikverkets ståndpunkter. Med hjälp av en analytisk modell görs sedan ett försök att härled effektiva marginalkostnadsbaserade och finansierande avgifter, samt ges ett räkneexempel med tänkbart utfall av marginalkostnadsbaserade avgifter. Sådana skulle eventuellt kunna leda till grannlaga fördelningspolitiska överväganden.

Normalt beräknas längsgående ojämnheter på svenska vägar med måttet International Roughness Index (IRI). Detta mått beräknas från en längsprofil, och beskriver den ackumulerade rörelsen mellan hjul och chassi (fjäderrörelse) på en kvartsbilmodell. Resultatet redovisas som fjäderrörelse per färdad längd, vanligtvis millimeter per meter. IRI-modellen beskriver endast rörelsen i vertikalled, dessutom med en ganska orealistisk fordonsmodell som alltid går i 80 km/h. Denna rapport redovisar arbetet med att ta fram en så kallad FullCar-modell (möjligtvis helbilsmodell på svenska, men jag fortsätter att använda ”FullCar” som en generellt beteckning i denna rapport) som kan användas för en mer realistisk modellering av ett fordons rörelser under normal färd. Fördelen med en, ur fordonssynpunkt, mer realistisk modell är att man kan konstruera mått som stämmer bättre överens med det som förare och passagerare upplever när de färdas på vägen. Det bör nämnas att det tidigare har visats att det finns en relativt hög korrelation mellan IRI och hur förare och passagerare upplever vägens tillstånd. En FullCar-modell borde dock kunna ge mer detaljerad information om vägytans effekt på fordonet. Till exempel skulle en lastbilsmodell kunna detektera avsnitt med farliga tvärfall. En realistiskt fordonsmodell skulle även kunna användas till nedbrytningsstudier av vägar, där vägytan dels slits av överfarter, dels deformeras av kontaktkrafter. Med en enkel modell skulle hundratusentals överfarter kunna simuleras på några minuter. In Sweden, longitudinal roughness has been more or less synonymous with the International Roughness Index (IRI). IRI is calculated from a longitudinal profile, and describes the accumulated movement between the wheel and chassis on a quarter-car model. The result is given as this movement divided with the traveled length. In Sweden, the unit millimeters per mere is normally used. The IRI-model is only affected by movements in the vertical direction, and the speed is fixed to 80 km/h. This report presents the work to make a full-car model, with the aim to produce a more realistic view of the movements of a vehicle traveling on a normal road. The benefits with a more realistic vehicle model is that indices with a higher correlation to drivers’ and passengers’ experiences can be made. It should be mentioned that a relatively high correlation between IRI and drivers’ estimates road condition has been shown. A FullCar model should, however, give more detailed information about the effect of the road surface on the vehicle. A truck model could, for example, be used to find sections with a dangerous cross fall. A realistic vehicle model could also be used in studies concerning the deterioration of roads, as the road is partly worn by wheel abrasions and partly deformed by contact forces. A simple model could simulate hundreds of thousands of vehicle passages in only a few minutes.

För att uppskatta hur trafikenergin påverkas av förbättrad vägytestandard behövs följande: • rullmotstånd som funktion av vägytans tillstånd • alla övriga färdmotstånd • bränsleförbrukning (Fc) som function av färdmotstånd. Huvudsakligen baserat på data från svenska coastdown-mätningar har en generell rullmotståndsmodell utvecklats. Denna modell använder följande förklaringsvariabler: vägojämnheter (iri), makrotextur (mpd), temperatur och hastighet. Modellen har kalibrerats för personbil, tung lastbil och för tung lastbil med släp. Rullmotståndsmodellen har integrerats i en bränslemodell med färdmotstånd som bas. Modellen har en hög förklaringsgrad. Färdmotståndsuttrycket i Fc-funktionen innehåller utöver vägytevariabler sådana för horisontell kurvatur (ADC) och lutning (RF). Om mpd per väglänk reduceras med upp till 0,5 mm, kommer den totala bränsleförbrukningen i vägnätet att reduceras med 1,1 %. Genom att reducera iri per länk med 0,5 m/km kommer hastigheten att öka parallellt med att rullmotståndet minskar, vilket har uppskattats resultera i att den totala bränsleförbrukningen i vägnätet approximativt blir oförändrad. Om spårdjup skulle reduceras parallellt med iri kan hastigheten förväntas öka ytterligare. Därmed skulle den resulterande bränsleeffekten bli en ökning. För enskilda väglänkar kan bränsleförbrukningen minska om andelen tung trafik är tillräckligt stor. In order to evaluate traffic energy changes due to the improvement of road surface standard one need to describe: • rolling resistance at different road surface conditions • all other driving resistance • fuel consumption (Fc) as a function of driving resistance. Based mainly on empirical data from coastdown measurements in Sweden a general rolling resistance model – with roughness (iri), macrotexture (mpd), temperature and speed as explanatory variables – was developed and calibrated for a car; a heavy truck and a heavy truck with trailer. This rolling resistance model has been incorporated into a driving resistance based Fc model with a high degree of explanation. The Fc function also includes variables for horizontal curvature (ADC) and the road gradient (RF). If mpd per road link is reduced by up to 0.5 mm, the total Fc in the road network will be reduced by 1.1%. By reducing iri per link by 0.5 m/km, speed will increase in parallel to reduced rolling resistance and there will be approximately no resulting effect on Fc. If rut depth is decreased in parallel to iri there will be a further increase in speed. For individual road links there might be an energy saving potential if the proportion of heavy vehicles is big enough.

The standard method of estimating the value of travel time variability for use in policy appraisal is to estimate the parameters of a reduced-form utility function, where some measure of travel time variability (such as the standard deviation) is included. A problem with this approach is that the obtained valuation will in general depend on the standardized travel time distribution, and hence cannot be transferred from one context to another. A recently suggested remedy of this problem has been to estimate a scheduling model, which in theory is transferrable, and use the implied reduced-form to derive valuations for use in appraisal. In this paper we estimate both a scheduling model and the implied reduced-form model, using stated choice data. The valuation of travel time variability implied by the scheduling model turns out to be substantially smaller than what is obtained from a reduced-form model estimated on the same sample. The results suggest that the scheduling model does not capture all of the disutility arising from travel time variability. Hence, although it can be shown that scheduling and reduced-form models are “theoretically equivalent”, that hypothesized equivalence is not reflected in the empirical evidence. We speculate that the derivation of reduced-form models from an underlying scheduling model omits two essential features: first, the notion of an exogenously fixed “preferred arrival time” neglects the fact that most activities can be rescheduled given full information about the travel times in advance, and second, disutility may be derived from uncertainty as such, in the form of anxiety, decisions costs or costs for having contingency plans. We also report our estimates of the valuation of travel time variability for public transit trips, for use in applied appraisal.

Baserat på så kallad coastdown-mätning har parametrar för färdmotstånd uppskattats för en tung lastbil med släp (60 ton) och med skåp som påbyggnad. Färdmotståndet vid en hastighet av 20 m/s, genomsnittliga vindförhållanden och 50 % lastfaktor fördelas med 5 % på transmissionsmotstånd, 41 % på rullmotstånd och 54 % på luftmotstånd. Mätningar har också utförts med lastbil utan släp. Rullmotstånd beror av vägytans ojämnhet (iri) och makrotextur (mpd). Det totala rullmotståndet kan indelas i: basmotstånd (plan yta), motstånd av iri och motstånd av mpd. På mätsträckan utgör vägyteeffekten cirka 40 % av det totala rullmotståndet. Ojämnhetseffekten bedöms utgöra den dominerande delen av vägyteeffekten till skillnad från lätta fordon. Parametrar ingående i funktioner för färdmotstånd har uppskattats med statistisk analys. Ett problem i detta sammanhang är hur större korrelationer mellan de ingående förklaringsvariablerna skall kunna undvikas. En målsättning i försöksuppläggningen har varit att undvika sådana beroenden. Föreliggande studie bör kunna vara av metodintresse avseende följande punkter: mätsträckans lutning, bestäms med hög noggrannhet (avvägning), och övriga vägytedata ingår i analysen fordonsvikt, uppföljning från utrullning till utrullning utrustningen för registrering av utrullningsförloppen (Dopplerteknik) separering av olika delar av färdmotståndet By use of coastdown measurements, driving resistance parameters have been estimated for a truck with trailer (60t) and a box vehicle body. At a vehicle speed of 20 m/s, average meteorological wind conditions and a load factor of 50% the following distribution of the driving resistance components has been obtained: transmission resistance (churning losses), 5% rolling resistance (test route surface conditions), 41% air resistance, 54%. There are also measurements for the truck without a trailer. Rolling resistance is dependent on road surface conditions, in particular roughness (iri) and macro texture (mpd). The total rolling resistance consists of three parts: a basic, an iri and a mpd part. The road surface effect amounts to approximately 40% of the total rolling resistance. The iri effect seems to be the dominating part of the surface effects on the contrary to light vehicles. Driving resistance parameters have been estimated by means of regression analysis. A major problem is how to avoid high correlations between explanatory variables. One objective of the experiment design has been to minimize such dependencies. This study might also be of interest for methodological reasons and in particular for including: the introduction of high accuracy road gradients as well as other road surface properties the estimation of vehicle mass from coastdown to coastdown the equipment (based on Doppler technique) used in order to measure the coastdown driving pattern the method used in order to separate parts of the driving resistance

The presence of distortive taxation and agglomeration benefits in the labour market means that there are benefits and losses not captured by standard cost-benefit analyses of transport policy measures. Recent theoretical analyses have raised concerns that the labour market effects of congestion charges may constitute considerable losses in the form of reduced aggregate labour income, over and above what is captured by the consumer surplus in the standard analysis of congestion charges – possibly to the extent that congestion charges may reduce aggregate social welfare, contrary to conventional wisdom in transport economics. The sign and size of these effects are an empirical question, however. We investigate this issue by estimating the labour income effects of the Stockholm congestion charges, using an estimated relationship between workplace accessibility and labour income. Results show positive effects on labour income, meaning that the “wider economic benefits” of this system are in fact benefits, not losses. It turns out to be crucial that the model accounts for value-of-time heterogeneity in the income/accessibility relationship and in the calculation of generalized travel costs.

Det saknas idag tillfredsställande effektmodeller för beräkning av konsekvenser och kostnader för trafikanterna av olika underhållsstrategier. Det största problemet identifierat av Trafikverken/Vägverken i Finland, Sverige, Norge och Estland är sambandet mellan vägytans tillstånd och olyckor, effekten av den viktigaste tillståndsparametern spårdjup för trafikantkostnaderna, liksom betydelsen av trafikantkostnaderna/- effekterna för ett vägnät som är i ett huvudsakligen gott tillstånd. Detta är problem som måste lösas för att bättre kunna rättfärdiga budgettilldelningen för vägunderhåll. VTI har därför i uppdrag på finska Trafikverket och med finansiering även från de övriga Trafikverken/Vägverken, genomfört en studie för att avgöra hur spårdjup påverkar olycksrisken för trafikanter. Separata analyser har gjorts för data från Sverige, Finland respektive Norge. Det antogs att olycksrisken också beror på andra vägtillståndsvariabler, t.ex. längsgående ojämnhet, textur, tvärfall, geografiskt läge (land), fordonsflöde, klimat, väderförhållanden etc. En modellansats valdes som skulle kunna hantera påverkan av alla dessa övriga vägtillståndsvariabler, samt eventuella interaktioner mellan dessa, på olycksrisken. Det antogs vidare att förhållandet mellan olycksrisk och spårdjup inte nödvändigtvis är en linjär funktion, varför spårdjup delades upp i ett antal kategorier. Det beslutades också att separata ekvationer skulle härledas för olika hastighets- och ÅDT (Årsmedeldygnstrafiken)-klasser. Spårdjupskategorier samt hastighets- och ÅDT-klasser valdes för att matcha varje lands strategier för underhåll. Den övergripande slutsatsen av analysen är att data inte ger stöd för några allmänna regler i en underhållsplan. Det finns inga resultat från studien som säger att djupare spår generellt tenderar att öka olycksrisken. Det finns heller inga resultat som säger att spår har samma påverkan på olycksrisken i olika ÅDT-klasser vid en given hastighet eller vice versa. Det tycks finnas en ökad risk vid spårdjup ? ca 15 mm i högsta hastighetsklassen, men resultaten skiljer sig åt mellan olika ÅDT-klasser och inte är lika i angränsande hastighetsklasser, vilket gör resultaten svåra att förstå och mindre användbara för att ange regler för underhåll. För norska data erhölls inte samma resultat i den högsta hastighetsklassen (> =90 km/tim), denna skiljer sig dock från de svenska och finska högsta hastighetsklasserna (> =110 km/tim-vägar respektive motorväg) There are currently no satisfactory effect models for calculating the consequences and costs for road users of different maintenance strategies. The main problems identified by the Transport/Road Administrations in Finland, Sweden, Norway and Estonia, are the relationship between road surface condition and accidents, the effect of the most important state parameter rut depth on road user costs, as well as the role of road-user costs/effects of a road network that is mostly in good condition. These are problems that must be resolved in order to better justify budget allocation for road maintenance. VTI has therefore on commission by the Finnish Transport Administration and with funding from the other Transport/Road Administrations conducted a study to determine the influence of rut depth effects on the accident risk of road users. Separate analyses were made of data from Sweden, Finland and Norway, respectively. It was assumed that the accident risk also depends on other road condition variables, such as longitudinal unevenness, texture, cross slope, geographic location (country), vehicle flow, climate, weather, etc. A model approach was chosen that could address the impact of all these other road condition variables, and the possible interactions between them, on the accident risk. It was assumed that the relationship between accident risk and rut depth is not necessarily a linear function, why rut depth was divided into several categories. It was also agreed that separate equations should be derived for different speed and AADT (Annual average daily traffic) classes. Rut depth categories, as well as speed and AADT classes were chosen to match each country's strategies for maintenance. The overall conclusion of the analysis is that the data does not support any general rules for a maintenance scheme. There are no results to show that deeper ruts generally tend to increase the accident risk. Nor are there results that show that ruts have the same influence on the accident risk for different AADT classes at a given speed or vice versa. There seems to be at increased risk for ruts ? about 15 mm in the highest speed class, but the results differ between AADT classes and are not similar in adjacent speed classes, making the results difficult to understand and less useful to specify the rules for maintenance. For the Norwegian data this trend can not be seen in the highest speed class (> = 90 km/h), but then this speed class differs from the Swedish and Finnish highest speed classes (> = 110 km/h roads and motorways, respectively).

We study the effect of uncertainty about the greenhouse gas emissions arising from the production of biofuels on trade policy, in the presence of lobby groups and two policy instruments, trade policy and biofuels mandates. We show that in the presence of biofuels mandates it would be optimal from a societal point of view to lower the trade tariff on biofuels when the emissions from their production are shown to be 'high' as compared to when they are believed to be 'low'. If the government is susceptible to lobbying, the tariff may be raised instead. We further show that at subsequent time periods, the biofuels sector's marginal lobbying effort will not fall compared to previous periods, and that consequently, its political contribution also does not fall. Finally we show how policy may be path dependent, i.e., that earlier tariff rates in part determine future tariff rates if the government is susceptible to lobbying and given that the domestic price of biofuels does not fall. The model can, e.g., shed light on why the EU does not lower the tariffs on Brazilian ethanol in the face of new information. Older version : http://swopec.hhs.se/vtiwps/abs/vtiwps2011_001.htm

A common approach for procuring large construction projects is through Unit Price Contracts. By the means of a simple model, we study the optimal quantity to procure under uncertainty regarding the actual required quantity given that the procurer strives to minimize expected total costs. The model shows that the quantity to procure in optimum follows from a trade-off between the risk of having to pay for more units than actually necessary and of having to conduct costly renegotiations. The optimal quantity increases in costs associated with possible renegotiations, decreases in expected per unit price, and, if a renegotiation does not increase per unit price too much, decreases in the uncertainty surrounding the actual quantity required. Older version: http://swopec.hhs.se/vtiwps/abs/vtiwps2011_004.htm

Denna rapport utgör slutrapportering i projektet ”ITS-stöd för miljövänlig körning” som utförts under 2009-2010 med finansiering från Trafikverkets FUD-program. Projektet har utförts av Sweco och VTI. Projektets syfte har varit att öka kunskapen kring hur kända och nya ITS-tillämpningar kan bidra till minskade koldioxidutsläpp i samband med vägtrafik. Fokus ligger särskilt på stödsystem för miljövänlig körning. Målsättningen har varit att kunna värdera existerande produkter och satsningar inom området men även att föreslå framtida lösningar och insatser inom området.

In this study we estimate the willingness to pay for railway noise abatements based on the effect of railway noise on property prices. We estimate both steps of the hedonic regression technique on a large data set of different Swedish regions which contains detailed information about railway noise along with socioeconomic characteristics for each property/household. The estimated demand relationship suggest welfare gains for a 1 dB reduction of railway noise as; 1240 SEK per individual and year at the baseline noise level of 71 dB, and 661 SEK at the baseline noise level of 61 dB. Below a noise level of 49.09 dB, individuals have no willingness to pay for railway noise abatements. In policy, these results can be used for cost benefit analysis and to derive marginal costs for infrastructure charges.

There are many methods for the solution of nonlinear programming (NLP) problems. This paper presents a new method, a heuristic, for the solution of large-scale separable NLP-problems. In this paper, separable NLP-problems are referred to a problem structure where each variable, in the problem, is only found in terms with a single variable. The method can tackle separable MINLP-problems as well. The proposed method is used to solve some smaller examples in order to show the usefulness of it on real problems.

VTI and the Norwegian Institute of Transport Economics (TØI) have at the request of the Swedish Road Administration carried out a research and development project concerning tourist routes in Sweden. The project was done in two parts, one literature study with examples of how other countries work with tourist routes and one field study about the opinions of visitors and business operators along two Swedish tourist routes (the present publication). The two tourist routes which have been studied are Tourist Route Gränna-Ödeshög-Rök in the Counties of Jönköping and Östergötland, and Tourist Route Kullaberg in the County of Skåne. The study of the experiences of the business operators, the visitors' willingness to pay and a deepened analysis of the landscape was only done along the Gränna route. As for the experiences of the visitors the data for the two Swedish tourist routes have been compared with similar data from a Norwegian tourist route, Tourist Route Sognefjell.

In diabetes mellitus pancreas fails to produce insulin enough to maintain tissue utilisation of blood glucose. To maintain a normalised metabolism many diabetic patients have to provide insulin from injections or an infusion pump. The disease affects some percent of western population. The insulin provided by the patient has to be adjusted to food and physical exercise. This may be achieved by following rules from diabetes professionals, but also by self learning how food, insulin and physical exercise interact and influence the blood glucose. It seems that the patients who have this intuitive knowledge of the interactions are the ones who manages their diabetes treatment best and have the highest quality of life. The learning have, however, been performed by trial and error - to the price of severe inconvenience and bad metabolic control. A combination of computer science and diabetes physiology has resulted in the computer program Särimner. It is created to give the user a possibility to experiment with diabetes treatment. Food, insulin and physical exercise may be varied and the blood glucose is calculated. Sarimner provides a short-cut to obtaining knowledge since it allows experiments, stimulates discussions and let the user by himself formulate and test hypotheses regarding experienced problems. Since Särimner may be adjusted to look more alike an individual, the experiments are driven by the user's own curiosity. He may experiment with situations of importance to himself and finally make himself the expert of his own treatment situation. The way Särimner is designed, allows interested users to get "under the skin" of the model and study details in the physiological processes. This transparency makes it possible to search for explanations to treatment phenomena. One drawback with the model is that it is quite complex and requires some knowledge from a user with the ambition to understand all the processes. To measure the impact of Särimner training, 11 diabetic teenagers were evaluated with respect to metabolic control, emotional adjustment, focus of control, self-esteem and ability to discuss treatment phenomena. No control group was possible to recruit. The results indicated that the education had been useful for some individuals. They increased their knowledge and ability to discuss treatment situations, their sense of control over the diabetes treatment, their self esteem and furthermore Särimner education may have caused a reduction of diabetes related stress. However, an increased level of diabetes related guilt did occur in some individuals, possibly due to either increased knowledge or a more internalised focus of control. The models ability to look alike reality is depending on for which purpose it is used. Even though it would be theoretically possible to fit the model to an individual, such an experiment would not be performable in reality since Särimner requires input data from the physiology which is impossible to measure. The properties of the model are, however, adequate for illustrating several treatment situations on a phenomenological level.

I rapporten presenteras en brottmekanisk modell kallad Fictitious Crack Model, FCM, med vilken det är möjligt att beräkna sprickbildning i trä.