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In the United States, freight transportation consumes 9% of all energy consumed and emits 12% of all CO2 emissions in the entire economy. Freight energy consumption and CO2 emissions have also been growing faster than those of other economic sectors since 1980. In response, this paper surveys freight energy consumption trends from both a modal-disaggregate (e.g. truck, rail, ship, etc.) and commodity-disaggregate (e.g. food products, wood products, consumer electronics, etc.) perspective. A systems approach is used to delineate the boundary between the freight systems and other economic systems with which it interacts, and to provide a framework for understanding the structure of freight. From a modal perspective, it is found that the amount of freight energy consumed by trucks has remained at about two-thirds of the total for the past two decades. However, there are also some recent examples of growing use of rail, which can be expanded to make U.S. freight less energy intensive. On the commodity side, freight energy use is found to be concentrated in a limited number of products, such as food products, farm products, and nonmetallic minerals, so that collaboration with these industries can provide a focal point for reducing freight energy. The subsequent discussion considers other factors such as changes to supply chains, impact of geographic patterns of freight, dematerialization of products, and transitioning to low-carbon fuels. [ABSTRACT FROM AUTHOR]

This paper investigates the application of linear regression models and modeling techniques in predicting freight generation at the national level within the U.S. Specifically, the paper seeks to improve the performance and fit of linear regression models of freight generation. We provide insight into different variable transformation techniques, evaluate the use of spatial regression variables, and apply a spatial regression modeling methodology to correct for spatial autocorrelation. We conclude that the spatial regression model is the preferred specification for freight generation at the national level. The proliferation of Geographic Information Systems (GIS) within planning agencies affords more widespread use of spatial regression and our results indicate this technique would provide improvement to models that have been traditionally limited by insufficient data. [ABSTRACT FROM AUTHOR]

This paper highlights geospatial science-related innovations and developments conducted by the Center for Transportation Analysis (CTA) at the Oak Ridge National Laboratory. CTA researchers have been developing integrated inter-modal transportation solutions through innovative and cost-effective research and development for many years. Specifically, this paper profiles CTA-developed Geographic Information System (GIS) products that are publicly available. Examples of these GIS-related products include: the CTA Transportation Networks; GeoFreight system; and the Web-based Multi-Modal Routing Analysis System. In addition, an application on assessment of railroad hazmat routing alternatives is also discussed. [ABSTRACT FROM AUTHOR]

Railroad transportation of hazardous materials did not receive as much attention as highway transportation in the academic literature, although comparable volumes are shipped via these two transport modes in North America and Europe. In this paper, we present an optimization methodology for the railroad tactical planning problem with risk and cost objectives. We determine the routes to be used for each shipment, the yard activities, and the number of trains of different types needed in the network. The transport risk assessment component of our model incorporates the differentiating characteristics of railroad operations. We develop a memetic algorithm-based solution methodology, which combines genetic and local searches, to solve the biobjective model. The railroad infrastructure in the midwestern United States is used as a basis for generating problem instances of the size encountered in real life. Our analyses of the solutions of instances indicate that it is possible to achieve significant reductions in population exposure without incurring unacceptable increases in operational costs. [ABSTRACT FROM AUTHOR]

This paper presents a decision tree model for evaluating countermeasures to reduce vulnerabilities to terrorism in commercial truck crossings at United States southwestern land ports of entry. The model includes critical events in four phases of cargo movement: cargo transfer in Mexico, Mexican customs, U.S. customs, and the inland phase. Improvements in transportation security, inspections at Mexican ports, and at U.S. ports, are comparatively evaluated using parameterized variables. Costs and benefits of such improvements are analyzed to counter a radiological dispersion device (also known as a "dirty bomb") attack. The results suggest that security decisions depend primarily on the probability of attack and parameters that influence the overall cost of false alarms. Extensive exploratory analysis reveals that improving security at Mexican ports is not recommended, mainly due to the cost of false alarms. However, a high percentage and a high cost of false alarms may justify new radiation portal monitors at U.S. ports even when improvements in the capability to detect dangerous cargo are insignificant. Better transportation security is not recommended if the probability of attack is less than 0.15. When the probability of attack exceeds 0.15 and false-alarm related costs are high, the model recommends enhancing transportation security. In addition, the parameters modeling economic consequences of an attack in a populated area, the probability of discovering weapons after smuggling into the United States, the probability of detonation, as well as the probability of detection at U.S. ports of entry, have significant impact on the countermeasure decision. [ABSTRACT FROM AUTHOR]

During the 1950s, the share of freight carried by railroads was similar and declining in both the United States and Europe. By 2000, the railroads’ share of freight (measured in ton–kilometers) had reached 38% in the United States while falling to 8% in Europe. This paper examines the reasons for the difference in rail’s share of freight in Europe and the United States. We find that almost 83% of the gap in 2000 is probably due to natural or inherent differences, principally geography, shipment distance, and commodity mix. However, 17% of the gap cannot be explained by these inherent differences and is presumably due to public policies including priority of passenger service, lack of interoperability at borders, service quality and rates, and incentives of the rail operators. We estimate that if that policy gap were closed, railroads’ share of freight in Europe would increase from 8% to 13%. [ABSTRACT FROM AUTHOR]

This paper studies the business cycle features of the transportation sector using dynamic factor models. The transportation reference cycles peak ahead of the economic cycles, but lag by a few months at troughs. The asymmetric relationship between these two suggests the usefulness of transportation in monitoring business cycles. [ABSTRACT FROM AUTHOR]

This paper investigates change in U.S. rail freight flows for the period 1972-81. Hypotheses about possible sources of change in the pattern of flows are generated within a spatial price equilibrium framework and then operationalized as a hierarchical set of Kullback-Leibler models representing inertia, variation in regional imports and exports, and variation in generalized interregional transport cost. Models are calibrated (1) for 1981 compared with all previous years and (2) for adjacent years in the data set. Hypotheses are tested using distribution-free methods. Results indicate that significant change in rail freight flows occurs more rapidly than can be accounted for by existing geographic theory. Change is primarily attributable to variation in regional imports and exports; variation in generalized transport cost is found to be considerably less important. [ABSTRACT FROM AUTHOR]

The transportation system infrastructure in the United States is vital to sustaining the nation's economy, safety, and well-being. In its recent special report, Potential Impacts of Climate Change on U.S. Transportation, the National Research Council concluded that climate change will have significant impacts on transportation systems, affecting design, construction, operation, and maintenance. Furthermore, the report calls for a focus on the problem now through adaptation planning to avoid costly future investments and disruptions to operations. This begins with sharing information, resources, best practices, and lessons learned across jurisdictional lines and among different stakeholders. With this in mind, a select group of stakeholders representing the freight-transportation industry and climate science participated in a summit held at Vanderbilt University in 2011, to reach consensus on the needs and challenges that must be addressed in order for successful adaptation strategies to emerge. This paper presents a brief review of the relevant literature on this topic, shares the outcomes and findings of summit deliberations, and provides recommendations for a path forward. [ABSTRACT FROM AUTHOR]

This paper describes the role of trucking in the U.S. economy; the major changes that have impacted the industry since the mid-1950s; its current and future position vs. other freight transportation modes, especially rail; and competition within the trucking industry. [ABSTRACT FROM AUTHOR]

Abstract: Travel behavior researchers have long been interested in various factors influencing how individuals make transportation decisions. Research has shown that foreign born residents and recent immigrants to the US exhibit significantly different travel behavior than native born populations in the same regions. This paper expands on that existing research by examining the travel behavior data of 662 students from Brigham Young University (52.1% of whom have lived outside the United States for more than 60 consecutive days). First the paper identifies if an individual’s experience living abroad results in a change in travel behavior upon their return to the United States; second, if the foreign location where the experience was gained influences any behavioral change, and if so which regions of the world produce the greatest influence?; and third, if the duration of an individual’s residence abroad affects their travel behavior and transportation perceptions upon returning to the United States. The analysis revealed that individuals who have lived abroad do exhibit a significant change in travel behavior upon returning to the United States, and the continent where the individual lived does significantly affect their change in travel behavior. However it appears that this change in behavior upon their return to the United States may be a regression to the mean, manifested by individuals adopting travel behavior similar to the transportation culture of their domestic environment. The location and duration of foreign experience does not have a significant impact on the current travel behavior of the individuals represented in this sample. [Copyright &y& Elsevier]

Abstract: Intermodalism has become one of the most significant transformations of freight transportation in the United States over the past two decades. The coupling of shipping modes has enabled shippers to more fully realize the respective time and costs advantages of respective modes. The opportunity to take advantage of intermodalism when shipping manufactured goods overseas may provide an essential competitive edge to a company or to an entire region engaged in world commerce. The change in the freight accessibility map of the United States to foreign markets that can be ascribed to intermodal infrastructures and operations has so far not been studied. With the help of a geographic information system, this paper analyzes this transformation in the United States by mapping integral place accessibility measures of five-digit zip code areas with respect to gateways for export of manufactured goods, especially containerized freight. The performance of the intermodal freight network is evaluated by comparing accessibility measures based on the highway network and on the intermodal network, respectively, for all North American container ports, as well as for subgroups of container ports on the Eastern Seaboard, the Western Seaboard, and the Gulf Coast of North America. The paper discusses regional winners and losers in the new national freight transportation system. [Copyright &y& Elsevier]

Railroads represent one of the most efficient methods of long-haul transport for bulk commodities, from coal to agricultural products. Over the past 50 years, the rail network has contracted while tonnage has increased. Service, geographically, has been abandoned along short-haul routes and increased along major long-haul routes, resulting in a network that is more streamlined. The current rail network may be very vulnerable to disruptions, like the failure of a trestle. This paper proposes a framework to model rail network vulnerability and gives an application of this modeling framework in analyzing rail network vulnerability for the State of Washington. It concludes with a number of policy-related issues that need to be addressed in order to identify, plan, and mitigate the risks associated with the sudden loss of a bridge or trestle. [ABSTRACT FROM AUTHOR]

Ever-escalating gasoline and diesel fuel prices in the United States (US) are prompting some states to temporarily suspend the collections of gasoline, and in fewer instances, diesel fuel, taxes. The focus of this paper is on the determinants of US state excise taxes levied specifically on diesel fuel. Among other things, we find the freight trucking industry’s contribution to total state employment is a highly significant determinant of a state’s diesel tax rate, consistently suggesting that the greater this contribution, the lower the tax rate, ceteris paribus. We find little evidence that the degree of freight transportation usage on state highways impacts diesel tax rates. These two findings taken together suggest that state legislators, when determining the diesel tax rate, exhibit behavior consistent with Stigler’s (Bell J Econ Manag Sci 2: 3–21, 1971) economic or positive theory of regulation. Moreover, state law makers appear less concerned over the impact that heavy freight transportation has on highway infrastructure, which appears to be at odds with the public interest or normative theory of regulation as articulated by Posner (Bell J Econ Manag Sci 4: 335–358, 1974). [ABSTRACT FROM AUTHOR]

Almost six years have elapsed since the passage of the Ocean Shipping Reform Act (OSRA), legislation that has led to significant changes in the structure of the US liner shipping industry. The European Union (EU) is poised to follow suit with the impending elimination of rule 4056/86, the block exemption from EU competition rules for liner shipping companies operating on European trades routes. The EU reform, however, is likely to go further than OSRA by prohibiting both conferences and discussion agreements on European trade routes. The outcome of such a policy is uncertain and the current review of it is several years old already. This paper is intended to provide some insight into the potential impact of regulatory reform in Europe, using the US experience as a benchmark. Specifically, the impact of OSRA with respect to industry structure, including its profitability, efficiency and what may be in store for the future is examined. [ABSTRACT FROM AUTHOR]

Electric and autonomous aircraft (EAA) are set to disrupt current cargo-shipping models. To maximize the benefits of this technology, investors and logistics managers need information on target commodities, service location establishment, and the distribution of origin–destination pairs within EAA's range limitations. This research introduces a three-phase data-mining and geographic information system (GIS) algorithm to support data-driven decision-making under uncertainty. Analysts can modify and expand this workflow to scrutinize origin–destination commodity flow datasets representing various locations. The algorithm identifies four commodity categories contributing to more than one-third of the value transported by aircraft across the contiguous United States, yet only 5% of the weight. The workflow highlights 8 out of 129 regional locations that moved more than 20% of the weight of those four commodity categories. A distance band of 400 miles among these eight locations accounts for more than 80% of the transported weight. This study addresses a literature gap, identifying opportunities for supply chain redesign using EAA. The presented methodology can guide planners and investors in identifying prime target markets for emerging EAA technologies using regional datasets. [ABSTRACT FROM AUTHOR]

Purpose: This paper seeks to pilot test a novel way to collect freight and service activity data and analyze the collected data in the metropolitan area of Medellin, Colombia.Methods: This research collects data using a multi-layer and multi-actor approach that includes surveys to receivers, suppliers, carriers, and truck drivers. The data are used by the authors to describe the overall freight patterns in the area of study and to show lessons learned.Results: The data collection resulted in 2947 establishments (4.4% of the total establishments in the city), a cordon survey of 2950 commercial vehicles (17% of the total vehicle volume) accessing the urban area, and carrier interviews to ten companies and 130 truck drivers. The results indicate that a total of 33,274 metric tons/day enter the study area, 35,240 tons/day leave the area; while 7000 tons/day are distributed in the study area. In terms of freight trips, 6600 trips/day enter the study zone and 6600 trips/day leave it.Conclusions: The data collection effort enabled the analyses of freight generation patterns. The freight surveys used in the study complement each other, and provided a good depiction of the freight movements in urban areas. It was found that in the Medellin Metropolitan Area, freight-intensive sector establishments generates, on average, significantly more cargo (freight attraction plus production) than the service-intensive sectors. The analyses of the surveys allow the decision makers to understand the nature of the cargo and the generation patterns in different type of establishments. This characterization of the freight patterns is vital for the forecasting of the behavior of the cargo and it is the main input to perform freight demand modeling for city planning, especially for developing countries, where there are too many budget constraints. [ABSTRACT FROM AUTHOR]

In this paper, the efficiency of the major US all-cargo carriers, both integrated and non-integrated, is measured and compared through a stochastic frontier analysis based on a translog cost function. Because of the high volatility of all-cargo traffic, especially since the 2008 economic crisis, and the increasing market share of integrators, this industry requires more detailed analysis. By using stochastic frontier analysis in this study, a distinction between random deviations from the production frontier and actual differences in technical efficiency is made. We find that smaller carriers react more flexible to a crisis and that non-integrated carriers are more efficient than the integrators when they are analysed jointly, which is however complicated by their different business models. These findings are not only useful for academics and industry actors, but also for policy makers, since air cargo contributes significantly to the profitability of airlines and airports. [ABSTRACT FROM AUTHOR]

Crew costs are a significant portion of rail operating expenses, and so effective deployment of train crews is an important priority for freight railroads. This paper proposes an optimization model and develops an effective solution approach to assign crews to trains and decide when to deadhead crew members in double-ended crew districts in U.S. freight railways. To solve this model quickly, we develop several modeling and methodological enhancements including methods to reduce the problem size, strengthen the model, and generate good heuristic solutions. Computational testing and validation using 140 real-life problem instances demonstrate that our algorithm can find optimal and implementable solutions very quickly (typically within one minute), making it well-suited for practical use to provide real-time decision support to crew planners. [ABSTRACT FROM AUTHOR]

There have now been over three decades of experience with rate-making freedom for all modes of intercity freight transport in the United States. Most evidence suggests that regulatory change has been beneficial for the rail industry and its users. Despite evidence of positive impacts of regulatory reform of U.S. freight transport, there is limited evidence related to long-term pricing trends by commodity in the deregulated era. Moreover, U.S. shipper groups have called for increased regulation of U.S. railroads, citing increased rates and profits, and monopoly pricing to 'captive shippers.' This study estimates U.S. railroad revenue-marginal cost ratios for seven different commodities between 1986 and 2008. Interestingly, we find no significant increase in revenue-cost margins for commodities thought to be 'most captive' (coal and chemicals), while finding large increases for some commodities thought to be 'non-captive.' These results may provide insight into the impacts of regulatory reform in other countries, where there are similar concerns of equitable pricing and financial viability. They suggest that a move toward a more market-based pricing system can enhance railroad viability without harming those with fewer transport options. [ABSTRACT FROM AUTHOR]

Abstract: This paper estimates the total embodied energy and emissions modal freight requirements across the supply chain for each of over 400 sectors using Bureau of Transportation Statistics Commodity Flow Survey data and Bureau of Economic Analysis economic input–output tables for 2002. Across all sectors, direct domestic truck and rail transportation are similar in magnitude for embodied freight transportation of goods and services in terms of ton-km. However, the sectors differ significantly in energy consumption, greenhouse gas emissions, and costs per ton-km. Recent pressure to reduce energy consumption and emissions has motivated a search for more efficient freight mode choices. One solution would be to shift freight transportation away from modes that require more energy and emit more (e.g., truck) to modes that consume and emit less (e.g., rail and water). Our results show there are no individual sectors for which targeting changes would significantly decrease the total freight transportation energy and emissions, therefore we have also looked at the prospect of policies encouraging many sectors to shift modes. There are four scenarios analyzed: (1) shifting all truck to rail, shifting top 20% sector mode choice, (2) based on their emissions, (3) based on a multi-attribute analysis, and (4) increasing truck efficiency (e.g., mpg). Increasing truck efficiency by 10% results in similar energy and emissions reductions (approximately 7% for energy and 6% for emissions) as targeting the top 20% of sectors when selected based on emissions, whereas selecting the top 20% based on availability to shift from truck results in slightly less reductions of energy and emissions. Implementing policies to encourage higher efficiency in freight trucks may be a sufficient short term goal while efforts to reduce truck freight transportation through sectoral policies are implemented in the long term. [Copyright &y& Elsevier]

Abstract: Government agencies can determine which specific facilities in a transportation network to restrict for each class of material and for which times of the day and/or week to stem the consequences of a terrorist event. To guide in making these determinations, this paper develops a three-player game of the interactions among a government agency, a carrier, and a terrorist. It also develops an effective solution procedure for this game and illustrates the use of that procedure on a realistic case study based on the freight rail network in the continental United States. [Copyright &y& Elsevier]

Abstract: In this paper we develop a model which approximates the upstream supply chains for embodied transportation in products. The sector with the largest embodied freight transportation in consumption is petroleum products followed by government services, construction, and food products. Overall, pipeline contributes 7% to the total embodied freight movement per sector, air transport is generally under 1%, water is 5%, and rail and truck transportation are the most dominant modes (14% each) for domestic freight transportation for the average sector. International water is the largest mode (60%) even compared to domestic modes, and international air contributes less than 1%. [Copyright &y& Elsevier]

This paper presents an energy and environmental network analysis model to explore tradeoffs associated with freight transport. The geospatial model uses an intermodal network built by the authors to connect various modes (rail, road, water) via intermodal terminals. Routes along the network are characterized not only by temporal and distance attributes, but also by cost, energy, and emissions attributes (including emissions of carbon dioxide, particulate matter, sulfur oxides, volatile organic compounds, and oxides of nitrogen). Decision-makers can use the model to explore tradeoffs among alternative route selection across different modal combinations, and to identify optimal routes for objectives that feature energy and environmental parameters (e.g., minimize carbon dioxide emissions). The model is demonstrated with three case studies of freight transport along the U.S. eastern seaboard. [ABSTRACT FROM AUTHOR]

Abstract: This paper examines the determinants of truck accidents in the United States using a time series data set covering the period 1970–2001. Along with other factors, the effect of the Motor Carrier Act of 1980, which deregulated the trucking industry, is examined for its impact on truck accidents. In addition, the model accounts for the effect railroad freight mileage has on truck accidents. Empirically, alcohol consumption, the unemployment rate, and railroad activity were found to have significant effects on truck accidents while deregulation of the trucking industry did not have a statistically significant adverse effect on these accidents. [Copyright &y& Elsevier]

Abstract: In this paper, empty container movements in the Los Angeles and Long Beach (LA/LB) port area are studied in an effort to reduce congestion by optimizing the empty container reuse. The dynamic empty container reuse is modeled analytically, and techniques are developed to optimize empty container operations. Several case studies based on current and projected demand in the LA/LB port area are used to evaluate the proposed techniques. Simulation results demonstrate that significant cost and congestion reductions can be achieved in the area, through reuse of empty containers. [Copyright &y& Elsevier]

The paper presents a methodology for forecasting freight flows over regional transportation networks. This methodology may be used by state departments of transportation (DOTs), metropolitan planning organizations (MPOs) and county transportation planners as a planning tool for identifying the most heavily traveled links of transportation networks and determining the direction of flow for major commodity groups. The model may also be used to estimate the major routes for movement of hazardous materials and to ascertain the impact of freight flows on pavement maintenance. Application of the methodology to the state of New Jersey indicates that the most heavily freight-flow utilized routes are Interstate 80, New Jersey Turnpike, and Route 202. [ABSTRACT FROM AUTHOR]

The article focuses on an analysis of regulatory change in the transportation industry in the U.S. The paper develops and applies a model for analyzing regulatory change in the freight transportation industry. The model incorporates multiple product markets, multiple transport modes and imperfect competition between modes. An application of the model to consider some of the consequences of extending the Interstate Commerce Commission's agricultural exemption to railroads, for the movement of corn in the Midwest, is provided. Data to estimate transport demands were obtained from a survey of country grain elevator operators on shipments of corn originating in the Midwest and destined for interior, East Coast and Gulf Coast markets. ICC data were used to estimate rail cost functions, while survey data were used to provide truck rate functions, surrogates for truck supply functions. Computations indicate that while transport rates will generally rise after deregulation, rail rates will increase relatively more in markets characterized by low-volume or short-haul activity. This will encourage a redistribution of freight patterns between rail and truck.

This article focuses on a survey of the international freight forwarders' (IFFs) perspectives on electronic data interchange and information management issues. The sample for this study consisted of 441 U.S. based IFFs. Each company received two mailings of a six-page survey that dealt with strategic, operational, and tactical issues of IFFs. The two mailings consisted of a cover letter, a copy of the survey, and a postage-paid return envelope. An unusually high number of surveys were returned as undeliverable, reducing the effective sample size to 336. This high number was surprising, as this same sampling frame was used just three years previously. A total of 98 usable responses, representing an effective response rate of 29.16%, were received. Non-response bias was examined by comparing completed surveys received within 21 days of the initial mailing to those received after this time. The rationale behind such a comparison is that late respondents tend to have more in common with non-respondents than do early respondents. While the comparison of earlier and later respondents yielded a total of five statistically significant differences, nearly 100 separate variables were included in the survey. As a result, non-response bias does not appear to be a major problem in this study.

The past 15 years have seen important changes in public policies toward the trucking industry, including deregulation, the imposition of a nationwide 55 mile per hour speed limit and significant changes in the stock of capital invested in the nation's highway system. The last of these changes entailed a substantial increase in the nation's highway stock in the 1960's through the mid-1970's. Since that time, however, it is widely believed that the system has not been kept up to earlier standards, with a resulting decline in highway capital stock likely. The main purpose of this paper is to analyze the effects of the last two of these policy changes on productivity in trucking over the last twenty years. It will also provide some tentative evidence of the effects of deregulation on costs for some large trucking companies. Although it is possible to suggest the directions of these effects a priori, it is impossible to do so with certainty. In the case of the 55 mph speed limit, faster speeds mean better utilization rates of the trucks and drivers but they also mean higher fuel consumption, and if the trucks are not engineered to operate at very high speeds, they can mean higher operating costs as well, so the direction of the effect is ambiguous.