<?xml version="1.0" encoding="utf-8"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>TRB Publications Index</title><link>http://pubsindex.trb.org/</link><atom:link href="http://pubsindex.trb.org/common/TRIS Suite/feeds/rss.aspx?tc=NN%3AKadr%2A" rel="self" type="application/rss+xml" /><description></description><language>en-us</language><copyright>Copyright © 2015. National Academy of Sciences. All rights reserved.</copyright><docs>http://blogs.law.harvard.edu/tech/rss</docs><managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor><webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster><image><title>TRB Publications Index</title><url>http://pubsindex.trb.org/Images/PageHeader-wTitle.png</url><link>http://pubsindex.trb.org/</link></image><item><title>Development of a Consumption-Weighted Benchmarking Methodology for Asphalt Cradle-to-Gate Global Warming Potential in Colorado</title><link>http://pubsindex.trb.org/view/2571942</link><description><![CDATA[Green public procurement policies in the United States are beginning to require benchmarking of construction materials’ global warming potential (GWP) values for government environmental policies and programs. At the state level, Buy Clean legislation requires state transportation departments to measure and reduce the greenhouse gas emissions of construction materials. This study proposes a cradle-to-gate (A1 to A3 life cycle phases) GWP benchmarking methodology for hot-mix asphalt mixtures in Colorado. Statistical analysis of GWP results and a review of Colorado Department of Transportation (DOT) asphalt mixture types indicate that Colorado GWP asphalt benchmarks should be subdivided into five primary mixture types. For each of the five mixture types, a limit value benchmark data set was generated from published Environmental Product Declarations (EPD) data, and a reference value benchmark data set was generated from job mix formulas submitted to Colorado DOT projects. The reference value benchmarks were consumption weighted by the quantity of the mix placed on Colorado DOT projects. The limit value data set and reference value data set were divided into percentiles (or quantiles) to compare with industry averages and national benchmarks. For the five primary mixture types, the average Colorado DOT consumption-weighted reference value was 5% to 29% higher than the average GSA national benchmark value as a result of the required inclusion of a minimum of 1% hydrated lime in Colorado DOT mixtures, which highlights the need for regional data when calculating local or state benchmarks. The reference value benchmark results indicate that consumption weighting yielded slightly different GWP values than an unweighted analysis, but with meaningfully different procurement implications.]]></description><pubDate>Thu, 10 Jul 2025 16:39:44 GMT</pubDate><guid>http://pubsindex.trb.org/view/2571942</guid></item><item><title>Determining the Impacts of COVID-19 on Urban Deliveries in the Metropolitan Region of Belo Horizonte Using Spatial Analysis</title><link>http://pubsindex.trb.org/view/1927424</link><description><![CDATA[The COVID-19 pandemic has changed lifestyles, with consequent impacts on urban freight movements. This paper analyzes the impacts of COVID-19 on urban deliveries in the Belo Horizonte Metropolitan Region, Brazil. The Lee index and the Local Indicator of Spatial Association were calculated using data on urban deliveries (retail and home deliveries) and COVID-19 cases. The results confirmed the negative impacts on retail deliveries and the positive impacts on home deliveries. The spatial analysis demonstrated that the most interconnected cities presented more similar patterns. At the beginning of the pandemic, consumers were considerably concerned about the virus spread, and the changes in consumption behavior were slow. The findings suggest the importance of alternative strategies to traditional retail. In addition, the local infrastructure should adapt to the increased demand for home deliveries during pandemics.]]></description><pubDate>Fri, 18 Mar 2022 08:39:17 GMT</pubDate><guid>http://pubsindex.trb.org/view/1927424</guid></item><item><title>A Microeconomic Theory–Based Latent Class Multiple Discrete–Continuous Choice Model of Time Use and Goods Consumption</title><link>http://pubsindex.trb.org/view/1439207</link><description><![CDATA[A microeconomic theory–based multiple discrete–continuous choice model was developed to accommodate (a) both time allocation and goods consumption as decision variables in the utility function, (b) both time and money budget constraints governing the activity participation and goods consumption decisions, (c) a finite probability of zero consumption and zero time allocation (i.e., corner solutions), and (d) technical constraints in the form of minimum consumption levels for any good that would be consumed and minimum time allocation for any activity conducted. The proposed model was applied in the form of a latent class model (to consider heterogeneity) on a Dutch data set to understand the determinants of weekly time use and goods consumption behavior.]]></description><pubDate>Mon, 20 Mar 2017 09:23:33 GMT</pubDate><guid>http://pubsindex.trb.org/view/1439207</guid></item><item><title>Impact of Transit Fare Increase in Caracas, Venezuela: Analysis Using PECAS Model</title><link>http://pubsindex.trb.org/view/1437742</link><description><![CDATA[A spatial economic framework for forecasting and policy analysis originally developed and mainly used in North America was applied to Caracas, Venezuela. This paper presents the application of the framework to analyze the spatial and economic implications of a policy of increasing public transit fares. The model shows the policy’s impact on the location of households and enterprises, as well as the impact on the spatial production and consumption of goods, services, labor and space. Changes in benefits are investigated, and are decomposed into components to identify the nature of winners and losers under the new scenario. Households responded to the higher transit fares by traveling less, and consuming services closer to home. Households out of poverty centralized, bidding up rents, leading to a decentralization of households in poverty, reinforcing socio-spatial segregation. Higher transport cost benefited some businesses by increasing their market dominance, however increases in wages paid counterpoise the higher commuting costs borne by employees. This test revealed how a model of interrelated spatial markets can help planners and policy makers understand potential and unexpected impacts in Caracas. This paper also identified the potential for improvements in the design of the model for Caracas. These would allow the Production, Exchange and Consumption Allocation System (PECAS) to serve as a more broadly applicable modelling framework for regions in developing countries]]></description><pubDate>Wed, 22 Feb 2017 17:01:11 GMT</pubDate><guid>http://pubsindex.trb.org/view/1437742</guid></item><item><title>Estimating the Loss of Consumption Due to Driving Cessation Among the Elderly Population</title><link>http://pubsindex.trb.org/view/1339431</link><description><![CDATA[As the number and influence of elderly persons in the United States grows, the changing transportation needs of this population will take on increasing importance.  According to the National Vital Statistics Report published by the Centers for Disease Control (2013), the life expectancy as of 2010 was 78.7 years, an increase from 77.0 years in 2000.  The elderly population will be expected to continue contributing to society as their numbers grow.  These contributions will be expected as many opt to limit or cease driving.  As a result, a given economy risks losing significant economic contribution due to the mobility loss experienced by elderly persons who do not drive.  Health and Retirement Study (HRS) data between 2000 and 2012 were used to determine driving ability.  Consumption and Activities Mail Survey (CAMS) data was then used to examine consumption patterns of the study group for certain categories.  Driving cessation was shown to be associated with a significant reduction in overall expenditures as compared to those who were able to continue driving, and is greatly influenced by land use characteristics. Society faces a significant potential economic loss as senior mobility declines. The transportation planning community’s ability to remove certain mobility barriers can mitigate these lost contributions.]]></description><pubDate>Fri, 27 Feb 2015 10:03:56 GMT</pubDate><guid>http://pubsindex.trb.org/view/1339431</guid></item><item><title>U.S. Freight Emissions Segmented by BCO Industry</title><link>http://pubsindex.trb.org/view/1242436</link><description><![CDATA[This paper estimates greenhouse gas (GHG) emissions from freight transport consumed by U.S. industries.  GHG emissions are allocated to detailed industry sectors.  The methodology described here uses ton-mile estimates by mode and commodity, allocates these ton-mile flows to producing industries in the U.S. Input-Output (I-O) Tables and estimates the consuming industries based on the relationships in the I-O table.  GHG emissions are estimated using ton-mile emission factors.  The results provide detailed data on the consumption of freight services and the energy intensity of these services.  The GHG emissions estimates include data on the GHG emissions associated with freight transport in international supply chains of U.S. companies.  These results can be used to benchmark the environmental footprint of U.S. industries and provide insight into where the greatest opportunities for GHG emissions reductions exist.]]></description><pubDate>Wed, 27 Feb 2013 09:22:28 GMT</pubDate><guid>http://pubsindex.trb.org/view/1242436</guid></item><item><title>Impact of Climate Change on Use of Anti-Icing and Deicing Salt in Sweden</title><link>http://pubsindex.trb.org/view/1138889</link><description><![CDATA[The future needs for winter maintenance will probably be influenced by the climate change in different ways in different parts of the world. As Sweden is a country with several climate zones, the influence of climate change on winter maintenance will therefore differ between regions within the country. To understand the influence of climate change on the future needs of salt consumption in winter maintenance, modeled road weather data were calculated in the IRWIN project (a joint research project through ERA-NET ROAD funded by the 6th Framework Program of the European Commission), where climate change scenarios from ECHAM5 (the fifth generation of the European Centre Hamburg Model general circulation model from the Max-Planck Institute for Meteorology) were combined with field data from the road weather information system in Sweden. These modeled road weather data were used in project KLIVIN (the study presented here) in three Swedish regions (Gothenburg, Stockholm, and Sundsvall) and was combined with the Swedish winter severity index in order to calculate the trends of future salt needs. In this study the needs of salt for each of the three investigated regions were calculated in 30-year periods between 1970 and 2100. The results show that salt use related to snowfall will decrease in all three regions, while the salt use related to temperature will increase in the northernmost region (Sundsvall) and show a small decrease in the two other regions (Gothenburg and Stockholm).]]></description><pubDate>Fri, 25 May 2012 10:32:55 GMT</pubDate><guid>http://pubsindex.trb.org/view/1138889</guid></item><item><title>Freight Generation, Freight Trip Generation, and Perils of Using Constant Trip Rates</title><link>http://pubsindex.trb.org/view/1091619</link><description><![CDATA[Several findings call into question current practices. The chief conclusion is that the accuracy of freight generation (FG) and freight trip generation (FTG) models depends on the consistency between the model’s structure and actual FG-FTG patterns, the degree of internal heterogeneity of the economic and land use aggregation used to estimate the model, and the appropriateness of the spatial aggregation procedure used to obtain the desired FG-FTG estimates. Relative to model structure, the paper establishes strong reasons to treat FG and FTG as separate concepts, because the latter is the output of logistic decisions, whereas the former is determined by the economics of production and consumption. The connection between business size variables—for example, employment—and FG is relatively strong because they are economic input factors, whereas the one with FTG is weaker because inventory and transportation costs come into play. Thus it is generally not correct to assume proportionality between FTG and business size or to assume that using constant FTG rates could be problematic. For instance, only 18% of the industry sectors in New York City exhibit constant FTG rates per employee. For economic and land use aggregation, the finer the level of detail the better, as independent variables have a better chance to explain FG-FTG. In the case of spatial aggregation, the correct aggregation procedure depends on the underlying disaggregate model. For a FG-FTG model to work well, both economic and land use and spatial aggregations must be appropriate.]]></description><pubDate>Fri, 29 Apr 2011 07:36:43 GMT</pubDate><guid>http://pubsindex.trb.org/view/1091619</guid></item><item><title>Entry-Only Automated Fare-Collection System Data Used to Infer Ridership, Rider Destinations, Unlinked Trips, and Passenger Miles</title><link>http://pubsindex.trb.org/view/880851</link><description><![CDATA[All U.S. transit agencies receiving FTA Urbanized Area Formula Program funding under Section 5307 (Section 15) report service consumption statistics (revenue passenger miles and unlinked trips) to the National Transit Database. Passenger miles is an incentive-based funding element that generates millions of dollars annually for New York City Transit (NYCT). Originally, Section 15 random sample data were collected by surveyors gathering passenger destination information, followed by manual distance calculation based on judgment of likely travel paths. This method was costly, inefficient, inconsistent, and not always reproducible despite rigorous auditing and certification. NYCT modernized this process by directly retrieving passenger-origination information from the automated fare-collection (AFC) system, inferring destinations with a second swipe, and automating passenger mile calculation by using schedule-driven shortest-path algorithms. While using state-of-the-art data collection and computation methods, NYCT retained FTA-approved sampling methodology to maintain comparability of data. Success of automated data reporting is maximized by developing algorithms first by using small data sets, followed by clearly documented parallel testing with full involvement of data consumers, including relevant regulatory authorities. Software development is iterative, and computation time should be monitored to ensure scalability. Building on this work, NYCT is developing AFC-based methodologies to infer bus passenger origins and destinations and train loads and it is adapting signal-system data for routine monitoring of operating performance. Reporting automation to the extent at which live data can be used for scheduling and service planning without modeling or special analyses will allow service to be monitored much more frequently and extensively.]]></description><pubDate>Wed, 27 May 2009 10:17:44 GMT</pubDate><guid>http://pubsindex.trb.org/view/880851</guid></item><item><title>Modeling Influence of Temporal and Monetary Constraints on Activity Participation, Travel, Consumption of Goods, Residential Location, and Work Status: Application in Land Use-Transport Interaction Model</title><link>http://pubsindex.trb.org/view/880555</link><description><![CDATA[The impact of income and monetary budgets on activity participation and travel, in relation to the costs of activities, travel and goods has received limited attention in the land use and transport modeling arena. Micro-economic approaches have accounted for the existence of time and money constraints, but make rather rigid assumptions about the relationship between expenditures and duration of activity participation. This paper proposes a more flexible approach in which money can be allocated to activities such as to increase their utility or decrease their duration. The allocation model is embedded in a land use transport interaction (LUTI) model, that also includes longer-term decisions regarding residential location, work location and work hours. The model is demonstrated in a series of simulations.]]></description><pubDate>Tue, 19 May 2009 07:48:44 GMT</pubDate><guid>http://pubsindex.trb.org/view/880555</guid></item><item><title>Modal Choices and Spending Patterns of Travelers to Downtown San Francisco, California: Impacts of Congestion Pricing on Retail Trade</title><link>http://pubsindex.trb.org/view/882238</link><description><![CDATA[Congestion pricing is a demand management strategy implemented on roadways to reduce traffic congestion, improve mobility, and encourage public transit ridership. The San Francisco County Transportation Authority in California is determining the feasibility of pricing to manage congestion, which is most severe in the downtown, Civic Center, and south of Market districts. These districts serve a variety of purposes that are not limited to office, restaurant, retail, hotel, and industrial and everyday attract a high number of workers and visitors—both local and tourist. The most vocal opponents to the potential congestion pricing program are downtown merchants. Many believe that their patrons primarily come by car and that drivers spend more money than transit riders and pedestrians. This study examined the travel to San Francisco’s major retail and entertainment centers and the spending patterns of those traveling to these centers, to assess whether these perceptions hold true. The survey found that most travelers get to downtown San Francisco by taking transit or walking, regardless of their income. Travelers using these modes spend more per month than those traveling by car, because they come more frequently to engage in recreational activities. The belief that recreational customers predominantly travel by car and spend more than transit riders is not reflected in the data, nor is this belief consistent with similar observations in other cities. Findings indicate the need for faster, more reliable multimodal transportation that supports a vibrant economy and provides viable travel choices to all.]]></description><pubDate>Mon, 30 Mar 2009 07:18:28 GMT</pubDate><guid>http://pubsindex.trb.org/view/882238</guid></item><item><title>Evidence of a Shift in the Short-Run Price Elasticity of Gasoline Demand</title><link>http://pubsindex.trb.org/view/801958</link><description><![CDATA[The short-run price and income elasticities of gasoline demand in the United States have been studied extensively by a number of authors.  Previous research has focused on the gasoline market during the 1970’s and 1980’s.  However, transportation analysts have hypothesized that behavioral and structural factors over the past several decades have changed the responsiveness of U.S. consumers to changes in gasoline price.  In this study we estimate the price and income elasticities of gasoline demand in two periods of similarly high prices from 1975 to 1980 and 2001 to 2006.  The estimated short-run price elasticities are approximately -0.30 and -0.04 for the earlier and more recent period, respectively.  The short-run income elasticity is approximately 0.50 and is not significantly different between the two periods.  These results have important policy implications.  In the short-run, consumers today appear significantly less responsive to gasoline price increases than in previous decades.  As a result, technologies and policies for improving vehicle fuel economy may become increasingly important for reducing U.S. gasoline consumption.]]></description><pubDate>Tue, 06 Mar 2007 14:38:11 GMT</pubDate><guid>http://pubsindex.trb.org/view/801958</guid></item><item><title>PREVENTING ALCOHOL-RELATED PROBLEMS: PUBLIC POLICY STRATEGIES</title><link>http://pubsindex.trb.org/view/754159</link><description><![CDATA[Traditionally, drinking prevention, especially for youth, has relied largely on educational and persuasive approaches.  Such approaches focus on changing knowledge and beliefs, teaching new skills, or modifying other individual-level mediating factors. Educational and persuasive approaches, however, cannot provide a complete answer to the problem of drinking by young people.  In part, this limitation arises because people are immersed in a broader social context in which alcohol is readily available and glamorized (Mauss et al., 1988).  In contrast, policy approaches address (a) formal legal and regulatory mechanisms, rules, and procedures for reducing the consumption of alcohol or risky drinking behaviors and (b) enforcement of these measures (Grube and Nygaard, 2001; Toomey and Wagenaar, 1999).  Policy approaches to prevention have considerable promise for addressing the problems associated with drinking by changing the legal and social environment.  In particular, policy strategies can be used to reduce alcohol availability, directly deter drinking by increasing the personal costs associated with it, and communicate norms regarding acceptable and unacceptable drinking practices.]]></description><pubDate>Tue, 22 Mar 2005 00:00:00 GMT</pubDate><guid>http://pubsindex.trb.org/view/754159</guid></item><item><title>CONSUMER AWARENESS OF MOTOR FUEL TAX RATES AND PRICES</title><link>http://pubsindex.trb.org/view/92970</link><description><![CDATA[MOTOR FUEL TAXES ARE ANALYZED AS A SOURCE OF STATE HIGHWAY FUNDS IN VIRGINIA. ABOUT 80 PERCENT OF ALL VIRGINIA HIGHWAY DOLLARS CURRENTLY COME FROM MOTOR FUEL TAXES, AND THIS STUDY EXAMINES EFFECTS OF THE TAX ON THE CONSUMPTION OF GASOLINE, ALONG WITH EVALUATING IT AS A CONTINUING SOURCE OF REVENUE. THE STUDY INVESTIGATES THE EXTENT TO WHICH VIRGINIA AND OUT-OF-STATE MOTORISTS WERE AWARE OF GASOLINE TAXES AND PRICES, AND EVALUATES DRIVER AND VEHICLE CHARACTERISTICS POSSIBLY INFLUENCING BUYING PATTERNS FOR GASOLINE. THE EXISTING VARIED PRICE STRUCTURE OF GASOLINE WITHIN GIVEN AREAS, THE GENERAL LACK OF TAX AND PRICE CONSCIOUSNESS OF THE GAS-BUYING PUBLIC, AND THE OVERALL GASOLINE BUYING HABITS OBSERVED INDICATE THAT AT PRESENT THERE IS NO WIDESPREAD RESISTANCE TO GASOLINE TAXES AS A SOURCE OF HIGHWAY FUNDS. ONLY A SMALL MINORITY OF ALL THE MOTORISTS INTERVIEWED KNEW THE DIVISION OF GAS TAXES BETWEEN STATE AND FEDERAL GOVERNMENTS, AND THERE WAS CONFUSION IN MOST MOTORISTS MINDS AS TO WHICH LEVIED THE LARGER AMOUNT. THE DATA INDICATED THAT OUT-OF-STATE DRIVERS ALSO BOUGHT GAS IN VIRGINIA AS THE NEED OCCURRED, AT WHAT MIGHT BE CONSIDERED NORMAL STOPPING TIMES, AND THAT THEY EXHIBITED A GENERAL LACK OF CONCERN FOR GASOLINE PRICES AND THE STATE-FEDERAL TAX RATES ON MOTOR FUEL.]]></description><pubDate>Fri, 18 Nov 1994 00:00:00 GMT</pubDate><guid>http://pubsindex.trb.org/view/92970</guid></item><item><title>ALCOHOL-RELATED ROAD ACCIDENTS IN THE FEDERAL REPUBLIC OF GERMANY</title><link>http://pubsindex.trb.org/view/390360</link><description><![CDATA[In the period from 1975 to 1990 there can be seen a favorable and continuous drop of alcohol-related road accidents in Germany.  This relatively favorable development among alcohol-related accidents is accompanied by a slight drop in alcohol consumption:  11.8 liters of pure alcohol per capita were consumed in 1990, a decrease of 10% when compared to 1980. In addition, a steady increase in soft drinks was found:  from 405.2 liters in 1980 to 513.0 liters in 1990, i.e., an increase of 26.5% (Kretschmer-Baumel).  Since the unification in 1990, in the New Lander, accidents in general and especially those concerning alcohol, have increased.  The recent figures, for 1992, which are still not official, show a stabilization and slight improvement in the New Lander.  This paper presents the statistics supporting these findings and offers perspectives on the process of social reorientation that is necessary to change dominant attitudes and to practice new behaviour modes of drinking-driving control.]]></description><pubDate>Thu, 05 May 1994 00:00:00 GMT</pubDate><guid>http://pubsindex.trb.org/view/390360</guid></item></channel></rss>