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Assessing the Value of Delay to Truckers and CarriersMiao, Qing 2010 December 1900 (has links)
This thesis evaluates the Value of Delay (VOD) to commercial vehicle operators due to highway congestions. The VOD for congestion is a fundamental parameter driving the private sectors’ response to public freight projects and policies such as corridor construction and tolling. Factors affecting the commercial VOD include direct operational cost, travel length, travel time variation, inventory holding, and warehouse management. To approach the VOD, two methods are adopted in this thesis. One is the Stated Preference (SP) survey. The other is carrier fleet operational simulation.
The simulation framework uses ArcGIS, and C . ArcGIS is used to generate a freight network based on the Houston, TX highway system. A set of customers are randomly generated, each having a random demand for service, which is associated with time windows for delivery and pickup. A heuristic algorithm is proposed to dispatch vehicles for truckload service on a continuous time horizon. The average VOD is then obtained through the ratio between additional operational cost and the delay caused by the congestion. This ratio is assessed in two scenarios: single depot and two cooperating depots. Different tests based on demand size, demand distribution pattern, time window and location of congestion are conducted. Simulation shows a range of VOD from $93.99/hr to $120.89/hr for the case of a central depot and $79.81/hr to $83.81/hr for the case of two depots.
In addition, a SP survey is conducted for truckers and carriers in two scenarios. The first scenario assumes a driver running late by 30 minutes on a congested road, while the second scenario assumes an on-time delivery or pickup. Several tolling alternatives are assumed to test the driver’s willingness to pay for using a hypothetical toll road. The data is then regressed with the logit model using maximum likelihood estimation to obtain perspective value of delay. A generic utility function is adopted, which results in a VOD range from $24.72/hr to $64.99/hr.
A comparison between the survey and the simulation results shows that drivers perceive a significantly lower VOD than the simulated VOD in freight operation.
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Investigation of an empirical methodology for linking value of time with census tract median incomeStockton, William Radney 15 May 2009 (has links)
This research examines a new methodology for prospectively estimating the
willingness of travelers to use a toll road by combining travel time saved with the
income of the prospective customer base. The purpose of the research is to facilitate
network level planning by allowing some reasonable predictions of acceptable toll rates
from readily available data and estimation techniques. Methods of estimating user
benefit resulted in simulated distributions of value of user time. Values of time are
linked to census tract income data for the user population to produce value of time as a
percentage of income as an indicator. As relevant literature acknowledges the tendency
toward increased toll road usage at higher income levels, it is hypothesized that linking
estimates of value of time directly to household income would produce a more useful
indicator of the travel market than do conventional indicators. Techniques for
prospectively estimating the travelshed of a toll road are compared with the actual
travelshed, as reflected in user home census tracts, as a means of evaluating the efficacy
of those techniques in estimating the market area of a prospective toll road.
Results show that considering value of time as a percentage of census tract
median income provides an improved portrayal of the toll road market, as usage of the
toll road increases with increasing income. Using census tract median income as the
income parameter has shortcomings, in that it produces anomalous results at very low
population levels. Of the two methods of estimating the travelshed, the visual estimation
approach was not satisfactory, leaving the analyst to use select link analyses instead.
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Quantifying Road User Costs with Heterogeneous Value of Motorists' Travel TimeTiwari, Shashank 16 December 2013 (has links)
The state transportation agencies (STAs) in the United States are mandated by federal rule to carry out work-zone impact assessment for highway rehabilitation projects. The work zone impact assessment requires calculating road user costs (RUCs) which is the sum of vehicle operating costs, accident costs, and value of time (VOT). The term ‘value of time’ refers to monetary equivalent of travel time wasted due to rehabilitation projects. In current practice, STAs assume VOT as homogeneous within their respective states. This leads to inaccurate RUCs calculations and poses many misapplications.
Research has found that VOT is influenced by socio-demographic variables which vary within the states. But there is a lack of framework to evaluate the extent to which these factors affect value of time. The major objective of this research is to develop and validate a model that predicts value of time heterogeneously.
The data were collected to cover 20 major cities in California. The state of California was chosen for this study because most highway rehabilitation projects are carried out there. The data sources included the United States Census Bureau, the California Department of Transportation (Caltrans), and the Bureau of Labor Statistics. With these data, a predictive model was developed using multiple linear regression analysis. Lastly, the model was validated using PRESS statistic. The results reveal that age, annual average daily traffic, and effective hourly income were the most significant factors influencing value of time.
This study developed a model which will help Caltrans in calculating value of time heterogeneously and therefore, improve the accuracy of RUCs calculations. Moreover, this research will serve as a guideline for other STAs to develop models for respective states. Therefore, this model has a potential to greatly improve the accuracy of value of time and therefore, RUCs.
The future research should focus on the identified factors, especially cost-of-living index and annual average daily traffic. Further research is required to account for heterogeneity due to other factors such as vehicle occupancy, frequency of travel, and educational qualifications.
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Consumer response to road pricing: Operational and demographic effectsSheikh, Adnan 07 January 2016 (has links)
The High Occupancy Vehicle (HOV) lanes on Atlanta, Georgia’s radial I-85 had long been providing sub-optimal throughput in the peak traffic hours, as the two-person occupancy requirement allowed the lanes to become heavily congested. The Georgia Department of Transportation converted 15.5 miles of HOV 2+ lanes to High Occupancy Toll (HOT) lanes, one in each direction on I-85. The lanes use dynamic value pricing to set toll levels based on the volume and average speed of traffic in the lanes. The goal of this research was to investigate the responses to toll lane pricing and the factors that appear to inform lane choice decisions, as well as examining values of travel time savings and toll price elasticity for users of the Express Lanes. This study of the metropolitan Atlanta I-85 Express Lanes operates at the microscopic level to examine the impact of demographic characteristics, congestion levels, and pricing on users’ decisions to use or not use the I-85 Express Lanes.
The dissertation examined the value of travel time savings distributions across income segments. The differences in these distributions among lower, medium, and higher income households were marginal at best. The results did not indicate that higher income households had the highest value of travel time savings results, as may have been expected. The modeling work performed here provided a number of insights into toll lane use. The determinants of lane choice decision-making in the morning peak had notable differences from the determinants of the afternoon peak. The initial analysis involved models which were estimated across three different income segments to examine differences in decision making between low, medium, and higher income households. The results indicated that the parameters were largely consistent across the three segments. Further segmenting the households showed that lane choice determinants varied more within the ‘Higher’ income segment than across the original three-segment structure. In particular, the five-segment models illustrated lower elasticities with regard to corridor segment counts and toll levels for the highest-income households in the sample, as well as higher household income level elasticities for afternoon trips by that same cohort.
The research was among the first in the available literature to use revealed preference lane use data for both the toll lane users and the unpriced general purpose lane users. The use of household level marketing data, rather than census or survey data, was another unique characteristic of this research. The analysis of value of travel time savings with a demographic component that looks at household income has not yet been seen in the literature; similarly, the findings regarding differing behavior among very high income households appear to be unseen in the existing literature. The results from this analysis, such as willingness-to-pay values for different population segments, will be useful inputs to the decisions surrounding future HOT implementations in the Atlanta region. The use of new data sources, the evaluation of those types of data sources, and the application of methods that have previously been unused in this field make up the primary contributions of this dissertation.
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A joint time-assignment and expenditure-allocation model: value of leisure and value of time assigned to travel for specific population segmentsHössinger, Reinhard, Aschauer, Florian, Jara-Díaz, Sergio, Jokubauskaite, Simona, Schmid, Basil, Peer, Stefanie, Axhausen, Kay W., Gerike, Regine January 2019 (has links) (PDF)
Based on a time-use model with a sound theoretical basis and carefully collected data for
Austria, the value of leisure (VoL) for different population segments has been estimated.
Through the combination of these results with mode-specific values of travel time savings
from a related study based on the same data, the first mode-specific values of time assigned
to travel (VTAT) were calculated. Data was collected using a Mobility-Activity-Expenditure
Diary, a novel survey format which gathers all activities, expenditures, and travel decisions
from the same individuals for 1 week in a diary-based format. The average VoL is
8.17 Euro/h, which is below the mean wage of 12.14 Euro/h, indicating that the value of work is,
on average, negative. Regarding the reliability of the VoL, we show its sensitivity to the
variance of working time in a sample, something that has been ignored in previous studies
and could be used to avoid inadequate segmentation. We controlled this effect in the
analysis of the heterogeneity of the VoL across the population by estimating the parameters
from the total (unsegmented) dataset with single interaction terms. We find that the VTAT
is strictly negative for walking, predominantly negative for cycling and car, and predominantly
positive for public transport with 0.27 Euro/h on average. The positive VTAT for public
transport is a strong indication for the importance of travel conditions, in turn suggesting
that improvements in travel conditions of public transport might be as important as investing
in shorter travel times.
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Choice set as an indicator for choice behavior when lanes are managed with value pricingMastako, Kimberley Allen 17 February 2005 (has links)
Due to recent pricing studies that have revealed substantial variability in values of time among decision makers with the same socioeconomic characteristics, there is substantial interest in modeling the observed heterogeneity. This study addresses this problem by revealing a previously overlooked connection between choice set and choice behavior.
This study estimates a discrete choice model for mode plus route plus time choice, subdivides the population according to empirically formed choice sets, and finds systematic variations among four choice set groups in user preferences for price managed lanes. Rather than assume the same values of the coefficients for all users, the model is separately estimated for each choice set group, and the null hypothesis of no taste variations among them is rejected, suggesting that choice set is an indicator for choice behavior.
In the State Route 91 study corridor, the price-managed lanes compete with at least two other congestion-avoiding alternatives. The principal hypothesis is that a persons willingness to pay depends on whether or not he perceives as personally feasible the option to bypass some congestion in a traditional carpool lane or by traveling outside the peak period. The procedure for estimating the choice sets empirically is predicated on the notion that individuals operate within a wide array of unobservable constraints that can establish the infeasibility of either alternative. The universal choice set includes eight combinations of mode and time and route, wherein there are exactly two alternatives for each. Choice sets are formed from an assumed minimum set, which is expanded to one of three others whenever a non-zero choice probability for either ridesharing, or shoulder period travel, or both is revealed in a persons history of choice behavior.
Based on the test of taste variations, this author finds different values of time across the four choice set groups in the study sample. If these relationships can be validated in other locations, this would make a strong case for modeling choice behavior in value pricing as a function of choice set.
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Understanding the Value of Travel Time Reliability for Freight Transportation to Support Freight PlanningShams, Kollol, 3085942 18 November 2016 (has links)
Today’s logistics practices are moving from inventory-based push supply chains to replenishment-based pull supply chains, leading to a lower and less centralized inventory, smaller shipment sizes, and more just-in-time deliveries. As a result, industries are now demanding greater reliability in freight transportation. Delays and uncertainty in freight transportation translate directly into additional inventory, higher manufacturing costs, less economic competitiveness for businesses, and higher costs of goods that are being passed on to the consumers. Given the growing demand in freight transportation, the emerging needs to better understand freight behavior for better policy and investment decisions, and the increasing role of reliability in freight transportation, this research aims at providing a) better understanding of how the freight system users value travel time reliability in their transportation decisions, and b) advanced methods in quantifying the user’s willingness to pay for the improvement of transportation related attributes, particularly travel time reliability.
To understand how the freight industry values travel time reliability in their transportation decisions, and particularly the presence of user heterogeneity, this research designed and conducted a stated preference (SP) survey for freight users in road transportation. Based on the feedback received during the pilot stage, reliability was measured as the standard deviation of travel time and presented as a frequency of on-time and late delivery in the choice scenarios. The survey collected 1,226 responses from 159 firms in Florida between January and May 2016 via online and paper methods.
Various modeling approaches were explored to estimate the willingness to pay (WTP) measures among freight users, including multinomial logit (MNL) and mixed logit model. Market segmentation and interaction modeling techniques were employed to investigate preference variations among user groups, commodity groups, product type, and various other shipment characteristics, including shipping distance and weight.
In general, across all groups in the sample, values of $37.00 per shipment-hour ($1.53 per ton-hour) for travel time savings and $55.00 per shipment-hour ($3.81 per ton- hour) for improvements of reliability were found in this research. Furthermore, while investigating the effects of shipping characteristics on the user’s preference in WTP, the results suggested that shipping distance and weight were the two most important variables.
The results of the study help advance the understanding of the impact of the performance of transportation systems on freight transportation, which will lead to policy and investment decisions that better serve the needs of the freight community.
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Is time money? Philosophical perspectives on the monetary valuation of travel timeNordström, Maria January 2020 (has links)
This licentiate thesis consists of an introduction (‘kappa’) and three papers discussing various aspects of time as a commodity and the practice of valuing travel time. The first paper is an analysis of the properties of time as an economic resource taking into account literature on behavior with regard to time. The intent is to provide better understanding of the underlying assumption of transferability between time and money in the context of transportation. The second paper builds on the analysis in the first paper combined with the findings of a study of commuters travel experiences during disruptions in the train traffic on the Øresund strait between Sweden and Denmark. It contrasts the theoretical account of value of travel time with the experiences reported by commuters and argues that the view of travel time as strictly a disutility can be limiting from a planning perspective. Instead, it is argued that an alternative approach can be to make travel time ‘plannable’, meaning viewing travel time as time travellers can plan to spend in a certain way at a certain time. The third paper argues that the diversity of possible mobility solutions based on self-driving vehicles has been somewhat overlooked in the current literature on value of travel time. Thus, the complexity of valuing travel time for self-driving vehicles has not been fully addressed. The paper consists of a morphological analysis of the parameters that might impact value of travel time for self-driving vehicles and a deeper analysis of five plausible self-driving vehicle mobility concepts. It is claimed that not all such concepts can be easily mapped into transport modes and that it might be more appropriate to differentiate value of travel based on travel characteristics. / Denna licentiatavhandling består av en introduktion och treartiklar som på olika sätt berör värdering av restid. Vare sigvi vill det eller inte är vår vardag driven av och bunden av tid.Vi planerar vår tid, spenderar vår tid och stressar när tideninte räcker till. Det vi önskar, vill och måste göra tar tid; tidenvillkorar helt enkelt mycket i våra liv. Om det är så att vi villförflytta oss från en fysisk plats till en annan, kanske mellanhem och jobb eller skola, tar det tid. Den här specifika tiden,restiden, antas behövas på grund av behovet av att jobba, fikaeller handla, inte genom en önskan om att resa i sig (även omdet självklart finns resor vi gör för nöjes skull, där nöjet är självaresan). I och med att resan (och restiden) är nödvändig men intei sig önskvärd är det ett grundläggande antagande inom fältetför transportekonomi att människor vill minimera sin restid i såstor utsträckning som möjligt. Det är det här antagandet sommycket av planeringen och investeringarna i transporter grundarsig på. Genom att undersöka betalningsvilja hos resenärer kanman sätta ett monetärt värde på potentiellt insparad restid: tidblir pengar. Men är det verkligen så enkelt? Till att börja medär tid och pengar de facto inte samma sak. Vi kan inte sparatid på samma sätt som pengar utan sparad tid måste användasomedelbart. Det blir därmed rimligt att anta att vad man gör medden insparade tiden spelar roll eftersom tiden känns mer värd omden kan spenderas på något meningsfullt. Vad man har möjlighetatt göra beror ofta på sammanhanget och upplevs därför mindreflexibelt än när det gäller insparade pengar.Denna avhandling resonerar vidare kring frågor om förhållandetmellan tid och pengar, i synnerhet den vanligt förekommandeoch generellt accepterade monetära värderingen av restid. Tillviss del problematiserar avhandlingen antagandet att tid är pengar och frågar sig om inte för mycket fokus läggs på tidskvantitetframför tidskvalitet och att kan det vara värdefullt att reflekterakring vilka transportinvesteringar som detta gynnar. Syftet äratt undersöka om de vedertagna transportekonomiska modellersom tillämpas idag speglar sådant vi som samhälle värdesätteroch lyfta aspekter som möjligen förbises.Introduktionen till avhandlingen består av en metodologiskdiskussion kring filosofins roll i tvärvetenskapliga projekt, enöversiktlig teoretisk bakgrund till begrepp såsom rationalitetoch välfärdsekonomi och en genomgång av teman som på etteller annat sätt berör värdering av tid. Därefter sammanfattasartiklarna och introduktionen avslutas med slutsatser och ettavsnitt om möjliga framtida forskningsämnen.Den första artikeln i den här avhandlingen handlar om hurförhållandet mellan tid och pengar kan bättre förstås genom attutgå från tiden som det primära att värdesätta. Denna analysoch de insikter som analysen leder till kan därefter förklara ochbättre underbygga antaganden som görs vid modellering av beslutrörande tid. I artikeln analyseras egenskaper av tid i relation tillpengar som framkommit i beteendevetenskaplig och psykologiskforskning. I transportekonomi, likt traditionell mikroekonomi,utgår man från ett antagande om stabila rationella preferenser hosindivider. Givet skillnader mellan hur individer verkar resonerakring tid jämfört med pengar kan man dock ställa sig frågan omdet skulle kunna vara annorlunda att vara rationell med avseendepå tid jämfört med att vara rationell med avseende på pengar. Isynnerhet då det finns egenskaper hos tid som är så pass specifikaatt motsvarande egenskaper inte finns hos andra typer av objekteller varor. Sammantaget hävdar vi att det enkla förhållandetmellan tid och pengar inte är tillräckligt rättfärdigat i ljuset av defaktiska skillnaderna mellan tid och pengar som verkar föreligga.Den andra artikeln i avhandlingen rör upplevelser av restid ochförhållandet mellan upplevelsen och de teoretiska antagandenasom görs i transportekonomi. I artikeln analyserar vi upplevelser av restid hos resenärer som påverkades av det plötsliga införandetav identitetskontroller vid resor mellan Sverige och Danmark 2015.Mot bakgrund av en studie där upplevelserna dokumenteradesvisar vi på aspekter av restid som upplevs men inte speglas i vedertagnatransportekonomiska modeller. Artikeln delar upp dessaaspekter i tre kategorier: (i) aspekter rörande den faktiska restatiden och upplevelser av själva resan, (ii) kortsiktiga anpassningartill rådande omständigheter och (iii) långsiktiga anpassningar tillrådande omständigheter. Vi menar att restiden behöver sättasi ett vidare perspektiv genom att se resan och restiden i ettsammanhang där planering av vardagen är en förutsättning föratt få livet att gå ihop. Ett möjligt sådant perspektiv är att urplaneringssynpunkt sträva efter att göra tiden så ‘planerbar’ sommöjligt, alltså att underlätta individers långsiktiga och kortsiktigaplanering av både restid och resor, istället för att enkom serestid som onytta.I tredje artikeln tillämpas till viss del insikter om vad som skiljertid från pengar och dessa appliceras på värdering av restid försjälvkörande fordon. Värdet av restid beror traditionellt (blandannat) på transportmedel, det vill säga om resan görs med bil,buss eller tåg. Självkörande bilar har i litteraturen setts som ytterligareresslag, ofta en ny sorts bil. Vi menar dock att självkörandefordon kan mynna ut i många olika typer av transportmedel därvissa kommer att likna de vi har idag medan andra kommer attvara nya sett till resegenskaper. Givet att dessa egenskaper är relateradetill aspekter som påverkar resenärers värdering av restidkommer tiden alltså vara olika mycket värd. Värdering av restidför självkörande fordon bli därför mer komplext än att lägga tillett eller ens några ytterligare transportmedel. För att belysa dettagör vi i artikeln en så kallad morfologisk analys där vi spännerupp ett lösningsfält vi menar täcker in aspekter som påverkarvärderingen av restid för självkörande fordon. Sedan analyserarvi möjliga (och troliga) lösningar, där varje lösning motsvararett möjligt transportmedel, och menar att restidsvärdet för dessa lösningar rimligen bör skilja sig åt. Det leder oss till att föreslåatt ett alternativt sätt att segmentera restidsvärde skulle kunnavara att utgå från resegenskaper, snarare än transportmedel somsådana. Sådana resegenskaper skulle kunna vara privat/deladresa eller om resan sker efter tidtabell eller är “on-demand“.Sammanfattningsvis menar jag att monetär värdering av tidkan ses från tre perspektiv: (i) det linjära förhållandet mellan tidoch pengar som sådant, (ii) aggregeringen av individers insparaderestid till faktisk samhällsnytta och (iii) restidsförkortningarsplats i kostnadsnyttoanalys och transportplanering i allmänhet.Transportinvesteringar görs på lång sikt och de samhällsekonomiskakalkyler som ligger till grund för dessa investeringar behöverdärmed spegla både vårt förhållande till tid idag men även hur vikommer att förhålla oss till tiden i framtiden. Rimligen kommervi då ha lika mycket tid som idag, men kommer vårt förhållandetill tid vara detsamma?Slutligen föreslår jag i avhandlingen möjliga framtida temanatt undersöka vidare, såsom transporträttvisa, aggregering avväldigt små restidsvinster och förhållandet mellan risker ochtidsvinster. / <p>QC 20200819</p>
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Global Demand Model to Estimate Supersonic Commercial ServicesFreire Burgos, Edwin Ruben 09 November 2021 (has links)
Not too long ago, commercial supersonic aircraft flights were part of the air transportation system. In the 1970's we had the Russian-built Tupolev Tu-144 and the BAC/Aerospatiale Concorde, the latest being tin operation for 27 years. The work documented in this dissertation focused on the viability of bringing back supersonic aircraft as a transportation mode. Throughout three years, Virginia Tech and a team from NASA have been combining efforts to develop a model capable of predicting future air travel demand for supersonic vehicles. The model can predict future supersonic commercial services and allows aircraft designers from NASA to optimize aircraft performance and characteristics by maximizing the potential air travel demand.
The final product of this study was the development of the Low-Boom Supersonic Aircraft Model (LBSAM). The development progress took three years to be completed, and during each year, a version of the model with the preliminary predictions was made available to NASA. Each of the three versions of the model predicts future supersonic commercial services. What differentiates each version is the data, method, and aircraft type/design implemented; the latest version of the model is more realistic and provides a higher number of functionalities.
The first version of the model predicted the possible supersonic commercial service for three aircraft types: each with two variations. An 18-seat, 40-seat, and 60-seat low-boom and non-low-boom aircraft were analyzed. The second version of the model analyzed a 20-seat and 40-seat low-boom, non-low-boom aircraft with restrictions and non-low-boom aircraft without restrictions. The latest version of the model tries to estimate potential demand for a 43-seat and a 52-seat supersonic low-boom aircraft design. The low-boom concept refers to the implementation of technology that reduces the loudness of a sonic boom. A non-low-boom concept refers to an aircraft flying faster than Mach 1 with the technology's implementation that reduces the loudness of a sonic boom. The final results suggest that for a 52-seat LBSA, the potential worldwide demand is as follows.
• 33.4 million seats worldwide. Assuming an overland range of 3,200 nm., an overland Mach 1.7, and an overland fuel scale factor of 0.98.
• 772 aircraft needed worldwide. Assuming an overland range of 2,800 nm., an overland Mach 1.7, and an overland fuel scale factor of 0.90.
• 1,032 one-way OD pairs where LBSA can operate. Assuming an overland range of 2,800 nm., an overland Mach 1.7, and an overland fuel scale factor of 0.90.
The LBSAM is mainly driven by the cost per passenger mile values calculated for each one-way Origin-Destination (OD) pair. Additional uncertainties in the model include the market share and annual aircraft utilization. The market share refers to the percent of the demand that will switch from current subsonic commercial services to commercial supersonic services. During the three-year work, we considered a market share of 50% and 100%. Aircraft utilization refers to the number of hours that the airline will be able to use the aircraft. The majority of the projections were based on a 3,500-hour aircraft utilization. / Doctor of Philosophy / Not too long ago, commercial supersonic aircraft flights were part of the air transportation system. An aircraft flying faster than the speed of sound is known as an aircraft flying at supersonic speed. Current commercial aircraft fly at subsonic speed. Subsonic speed refers to aircraft flying at a speed lower than the speed of sound. In the 1970's we had the Russian-built Tupolev Tu-144 and the BAC/Aerospatiale Concorde, the latest being tin operation for 27 years. The work documented in this dissertation focused on the viability of bringing back supersonic aircraft as a transportation mode. Throughout three years, Virginia Tech and a team from NASA have been combining efforts to develop a model capable of predicting future air travel demand for supersonic vehicles. The model can predict future supersonic commercial services and allows aircraft designers from NASA to optimize aircraft performance and characteristics by maximizing the potential air travel demand.
The purpose of this dissertation effort is to provide a better understanding of what could be the potential commercial demand for supersonic flight in the near future. We consider all the benefits and characteristics of supersonic flight and studied in detail what percentage of the travelers might be willing to migrate from the current subsonic market to the supersonic market. We estimated this ratio by studying the spending behavior of passengers in the current market. How much more are passengers willing to pay to save time? We can infer how much travelers value their time by comparing direct flights versus flights with an intermediate stop.
The results show that a demand of 33.4 million seats could be reached by the year 2040. The supersonic market would consist of more than one thousand one-way origin-destination pairs worldwide, and more than seven hundred supersonic aircraft are expected to satisfy the forecast demand.
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Modelling and Appraisal in Congested Transport NetworksWest, Jens January 2016 (has links)
Appraisal methodologies for congestion mitigation projects are relatively less well developed compared to methodologies for projects reducing free flow travel times. For instance, static assignment models are incapable of representing the build-up and dissipation of traffic queues, or capturing the experienced crowding caused by uneven on-board passenger loads. Despite the availability of dynamic traffic assignment, only few model systems have been developed for cost-benefit analysis of real applications. The six included papers present approaches and tools for analysing traffic and transit projects where congestion relief is the main target. In the transit case studies, we use an agent-based simulation model to analyse congestion and crowding effects and to conduct cost-benefit analyses. In the case study of a metro extension in Stockholm, we demonstrate that congestion and crowding effects constitute more than a third of the total benefits and that a conventional static model underestimates these effects vastly. In another case study, we analyse various operational measures and find that the three main measures (boarding through all doors, headway-based holding and bus lanes) had an overall positive impact on service performance and that synergetic effects exist. For the congestion charging system in Gothenburg, we demonstrate that a hierarchal route choice model with a continuous value of time distribution gives realistic predictions of route choice effects although the assignment is static. We use the model to show that the net social benefit of the charging system in Gothenburg is positive, but that low income groups pay a larger share of their income than high income groups. To analyse congestion charges in Stockholm however, integration of dynamic traffic assignment with the demand model is necessary, and we demonstrate that this is fully possible. Models able to correctly predict these effects highlight the surprisingly large travel time savings of pricing policies and small operational measures. These measures are cheap compared to investments in new infrastructure and their implementation can therefore lead to large societal gains. / <p>QC 20160829</p>
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