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Off-Highway Gasoline Consuption Estimation Models Used in the Federal Highway Administration Attribution Process: 2008 Updates

Description: This report is designed to document the analysis process and estimation models currently used by the Federal Highway Administration (FHWA) to estimate the off-highway gasoline consumption and public sector fuel consumption. An overview of the entire FHWA attribution process is provided along with specifics related to the latest update (2008) on the Off-Highway Gasoline Use Model and the Public Use of Gasoline Model. The Off-Highway Gasoline Use Model is made up of five individual modules, one for each of the off-highway categories: agricultural, industrial and commercial, construction, aviation, and marine. This 2008 update of the off-highway models was the second major update (the first model update was conducted during 2002-2003) after they were originally developed in mid-1990. The agricultural model methodology, specifically, underwent a significant revision because of changes in data availability since 2003. Some revision to the model was necessary due to removal of certain data elements used in the original estimation method. The revised agricultural model also made use of some newly available information, published by the data source agency in recent years. The other model methodologies were not drastically changed, though many data elements were updated to improve the accuracy of these models. Note that components in the Public Use of Gasoline Model were not updated in 2008. A major challenge in updating estimation methods applied by the public-use model is that they would have to rely on significant new data collection efforts. In addition, due to resource limitation, several components of the models (both off-highway and public-us models) that utilized regression modeling approaches were not recalibrated under the 2008 study. An investigation of the Environmental Protection Agency's NONROAD2005 model was also carried out under the 2008 model update. Results generated from the NONROAD2005 model were analyzed, examined, and compared, to the extent that is possible on ...
Date: December 1, 2009
Creator: Hwang, Ho-Ling & Davis, Stacy Cagle
Partner: UNT Libraries Government Documents Department

Final Report Phase I Study to Characterize the Market Potential for Non-Motorized Travel

Description: The idea of livable communities suggests that people should have the option to utilize non-motorized travel (NMT), specifically walking and bicycling, to conduct their daily tasks. Forecasting personal travel by walk and bike is necessary as part of regional transportation planning, and requires fine detail not only about individual travel, but also on transportation and neighborhood infrastructure. In an attempt to characterize the 'market' potential for NMT, the Office of Planning, Federal Highway Administration (FHWA) funded the Center for Transportation Analysis (CTA) of the Oak Ridge National Laboratory (ORNL) to conduct a study. The objectives of this effort were to identify factors that influence communities to walk and bike and to examine why, or why not, travelers walk and bike in their communities. This study relied on information collected under the 2009 National Household Travel Survey (NHTS) as the major source of data, and was supplemented with data from the American Community Survey (ACS), educational survey, health, employment, and others. Initial statistical screening methods were applied to sort through over 400 potential predictor variables, and examined with various measures (e.g., walk trip per person, walk mileage per person, bike trip per person, bike mileage per person) as the dependent variables. The best geographic level of detail used in the modeling for this study was determined to be the Census block group level for walking and Census tract level for biking. The need for additional supplemental private data (i.e., Walk Scores and Nielsen employment data), and geospatial information that reflects land use and physical environments, became evident after an examination of findings from the initial screening models. To be feasible, in terms of costs and time, the geographic scale of the study region was scaled down to nine selected NHTS add-on regions. These regions were chosen based on various criteria including ...
Date: June 1, 2012
Creator: Hwang, Ho-Ling; Reuscher, Tim; Wilson, Daniel W & Schmoyer, Richard L
Partner: UNT Libraries Government Documents Department

Incorporating environmental justice into environmental decision making

Description: Executive Order 12898, signed on February 11, 1994, broadly states that federal activities, programs, and policies should not produce disproportionately high and adverse impacts on minority and low-income populations. Moreover, the Order indicates that these populations should not be denied the benefits of, or excluded from participation in, these activities, programs, and policies. Because a presidential memorandum accompanying the order said that National Environmental Policy Act (NEPA) documents should begin to address environmental justice immediately, much attention has been paid to assessment-related issues. Also important, a topic that appears to have received relatively little attention, is how decision makers should be expected to use information about environmental justice in their decision making. This paper discusses issues surrounding the use of environmental justice information in the decision-making process by focusing on the following five main topics: (1) the importance, or weight, attached to environmental justice within larger decision-making contexts; (2) the potential tension between localized environmental justice issues and regional or national issues and needs; (3) the use of environmental justice information to develop (perhaps in concert with affected minority and low-income communities) appropriate mitigation strategies, or to establish conditions under which activities, programs, and policies may be accepted locally; (4) the general implications of shifting the distribution of broadly defined risks, costs, and benefits among different population groups; and (5) the implications of implementing environmental justice on an individual, ad hoc basis rather than within a larger environmental justice framework. This paper raises the issues and discusses the implications of alternative approaches to them.
Date: July 1, 1995
Creator: Wolfe, A.K.; Vogt, D.P. & Hwang, Ho-Ling
Partner: UNT Libraries Government Documents Department

New York State 2009 NHTS Comparison Report

Description: The U.S. Department of Transportation (USDOT) initiated an effort in 1969 to collect detailed data on personal travel, with the most recent surveys being the 1995 Nationwide Personal Transportation Survey (NPTS) and the 2001 and 2009 National Household Travel Surveys (NHTS). The primary objective of these surveys is to collect trip-based data on the nature and characteristics of personal travel so that the relationships between the characteristics of personal travel and the socio-economic and demographic characteristics of the traveler and his/her household can be established. In addition to the number of sample households that the national NPTS/NHTS survey allotted to New York State, NYDOT procured an additional sample of households in the 1995, 2001, and 2009 surveys. The comparisons drawn in this report compare the results from these NYS sampled households to the results from households drawn for the rest of the nation. Many of the differences between NYC counties and others in the state result from the striking differences in private vehicle ownership levels, with less than one in two NYC drivers and only 64% of NYC households owning a vehicle in 2009: versus 9 out of 10 drivers owning a vehicle, and between 1.5 and 2 vehicles owned per household, on the average, in the state's other metro areas. And this situation has changed very little over the past fourteen years covered by the three latest NPTS/NHTS surveys. While households in metro areas outside NYC do not own a vehicle largely due to income constraints, many households in NYC/Manhattan do not own a vehicle by choice. However, the statistics suggest that the mobility of zero-vehicle households in NYC/Manhattan is by no means deterred by the lack of a vehicle. While the private vehicle tripmaking rate of NYC residents was between one half and one third that in the ...
Date: June 2012
Creator: Southworth, Frank; Reuscher, Tim & Hwang, Ho-Ling
Partner: UNT Libraries Government Documents Department

Supply Chain Based Solution to Prevent Fuel Tax Evasion: Proof of Concept Final Report

Description: The goal of this research was to provide a proof-of-concept (POC) system for preventing non-taxable (non-highway diesel use) or low-taxable (jet fuel) petrochemical products from being blended with taxable fuel products and preventing taxable fuel products from cross-jurisdiction evasion. The research worked to fill the need to validate the legitimacy of individual loads, offloads, and movements by integrating and validating, on a near-real-time basis, information from global positioning system (GPS), valve sensors, level sensors, and fuel-marker sensors.
Date: December 1, 2011
Creator: Capps, Gary J.; Lascurain, Mary Beth; Franzese, Oscar; Earl, Dennis Duncan; West, David L.; McIntyre, Timothy J. et al.
Partner: UNT Libraries Government Documents Department

Modified seasonal factors in exponential smoothing

Description: Current practice uses statistical tests to determine whether seasonal factors should be applied in a given forecasting situation. Research suggests that an optimal policy might lie somewhere between using full seasonal factors and using no seasonal factors on series. This research proposes and tests use of a modified seasonality factor. Modified seasonal factors reduce the emphasis on the seasonal adjustments when forecasts are made. The adjustments account for errors in the estimation of the factors and for possible changes in the factors over the forecast horizon. An analysis of data from US Navy personnel inventories was conducted to test the use of a modified seasonality factor. Modified seasonal factors led to improved accuracy for predictions of inventories by paygrade using quarterly data from the Navy Personnel Research and Development Center (NPRDC). Under certain selections of factors, the mean absolute percent error (MAPE) was reduced by 4.4%. No gain was obtained, however, for the inventories by length of service. It is expected, but not shown here, that the modified seasonal factors will only be of value for series where the estimated seasonal factors show a substantial variation across the year. 3 refs., 6 tabs.
Date: September 1, 1990
Creator: Armstrong, J.S. (Pennsylvania Univ., Philadelphia, PA (USA). Wharton School of Finance and Commerce); Hwang, Ho-Ling (Oak Ridge National Lab., TN (USA)) & Bandy, J. (Tennessee Univ., Knoxville, TN (USA))
Partner: UNT Libraries Government Documents Department