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Area-normalized thematic views

Description: This paper presents a novel technique for dealing with a classic problem that frequently arises in visualization. Very expressive nonlinear transformations can be automatically generated to correct thematic maps so that the areas of map regions are proportional to the thematic variables assigned to them. This helps to eliminate one of the most commonly occurring visual lies that occurs in information visualization. Thematic variables are commonly used in cartography to encode additional information within the spatial layout of a map. Common examples of thematic variables are population density, pollution level and birth rate. The method is illustrated with two examples, mapping interstate speed limits and presidential election results.
Date: October 1, 1998
Creator: Keahey, T.A.
Partner: UNT Libraries Government Documents Department

A Model for Flow and Dispersion Around Buildings and Its Validation Using Laboratory Measurements

Description: Numerical modeling of airflow and pollutant dispersion around buildings is a challenging task due to the geometrical variations of buildings and the extremely complex flow created by such surface-mounted obstacles. The airflow around buildings inevitably involves impingement and separation regions, a multiple vortex system with building wakes, and jetting effects in street canyons. The interference from adjacent buildings further complicates the flow and dispersion patterns. Thus accurate simulations of such flow and pollutant transport require not only appropriate physics submodels but also accurate numerics and significant computing resources. We have developed an efficient, high resolution CFD model for such purposes, with a primary goal to support incident response and preparedness in emergency response planning, vulnerability analysis, and the development of mitigation techniques.
Date: May 17, 2000
Creator: Chan, S. T.; Stevens, D. & Lee, R.
Partner: UNT Libraries Government Documents Department

Overview of nondestructive evaluation technologies

Description: The infrastructure in the US and the world is aging. There is an increasing awareness of the need to assess the severity of the damage occurring to the infrastructure. Limited resources preclude the replacement of all structures that need repairs or have exceeded their life times. Methods to assess the amount and severity of damage are crucial to implementing a systematic, cost effective approach to repair and/or replace the damaged structures. The challenges of inspecting aging structures without impairing their usefulness rely on a variety of technologies and techniques for nondestructive evaluation (NDE). This paper will briefly describe several nondestructive evaluation technologies that are required for inspecting a variety of systems and structures.
Date: April 1, 1995
Creator: Thomas, G.
Partner: UNT Libraries Government Documents Department

EM modeling for GPIR using 3D FDTD modeling codes

Description: An analysis of the one-, two-, and three-dimensional electrical characteristics of structural cement and concrete is presented. This work connects experimental efforts in characterizing cement and concrete in the frequency and time domains with the Finite Difference Time Domain (FDTD) modeling efforts of these substances. These efforts include Electromagnetic (EM) modeling of simple lossless homogeneous materials with aggregate and targets and the modeling dispersive and lossy materials with aggregate and complex target geometries for Ground Penetrating Imaging Radar (GPIR). Two- and three-dimensional FDTD codes (developed at LLNL) where used for the modeling efforts. Purpose of the experimental and modeling efforts is to gain knowledge about the electrical properties of concrete typically used in the construction industry for bridges and other load bearing structures. The goal is to optimize the performance of a high-sample-rate impulse radar and data acquisition system and to design an antenna system to match the characteristics of this material. Results show agreement to within 2 dB of the amplitudes of the experimental and modeled data while the frequency peaks correlate to within 10% the differences being due to the unknown exact nature of the aggregate placement.
Date: October 1, 1994
Creator: Nelson, S.D.
Partner: UNT Libraries Government Documents Department

Safety and security issues in developing and operating in intelligent transportation systems

Description: The purpose of this panel is to introduce the safety and security issues related to the development and operation of Intelligent Transportation Systems (ITS) to Compass participants. Many of these issues need to be addressed by the system safety and computer security communities prior to the development and deployment of ITS. For example, how can information technology be applied in the context of a fully automated highway system (AHS) such that the safety, security, and performance of the system are not compromised? At present, the US and other countries are funding academia and industry to build prototype automated highway systems in which vehicles are controlled via drive-by-wire technology, with vehicles traveling at high speeds (in excess of 30 m/s) at close spacing (1 to 4 m). The potential impact of software errors or hardware errors on system safety and security are great.
Date: April 1, 1995
Creator: Lawrence, J.D.
Partner: UNT Libraries Government Documents Department

Independent seismic evaluation of the 24-580-980 south connector ramps

Description: The interchange for highways 24, 580, and 980 (the Stack) in Oakland, California, lies 4.3 km from the surface expression of the Hayward fault and 26 km from the San Andreas fault. The purpose of this project is to compute realistic, linear, strong ground motion (rock outcrop motion) likely to affect this interchange during a hazardous earth-quake on the Hayward fault. With the exception of very long period ( >20 sec) motion, the Hayward fault will be the controlling deterministic ground motion hazard to this structure. We identified a magnitude M = 7.25 earthquake that ruptures 82 km of the Hayward fault as the principal hazard to the Stack; it has a moment of 8.5 x 10{sup 26} dyne-cm. Moment magnitudes (Hanks and Kanamori, 1979) are used in this report. Our goal is to produce realistic synthesized ground motion for three components and the full wavetrain and for frequencies from 0.05 to 33.0 Hz.
Date: May 1, 1997
Creator: Hutchings, L.J.; Kasameyer, P.W.; Jarpe, S.P. & Foxall, W.
Partner: UNT Libraries Government Documents Department

Independent seismic evaluation of the 24-580-980 south connector ramps response to the south connector ramps to a magnitude 7.25 Hayward Fault earthquake. Volume 3

Description: The 24/580/980 interchange is located near Oakland California on the Eastern perimeter of the San Francisco Bay (Fig. 1 and Fig. 2). This interchange is a major artery in the Eastern San Francisco Bay area and provides a critical link between major bay area highways. The main Concord line of the Bay Area Rapid Transit System (BART), with ridership of approximately 270,000 per day, runs underneath the interchange. The interchange site is approximately 4 Km from the Hayward fault and 16 Km from the San Andreas fault. The reinforced concrete interchange was designed and constructed in the mid 1960`s and thus the asphalt structure has many of the vulnerabilities associated with typical pre-1970`s concrete structures (Roberts [1], Zefinski [2], Chai et. al. [3], Priestly and Seible [4]). In 1980 some of the seismic vulnerabilities were addressed as the interchange was retrofit with deck hinge restrainers as part of the California Department of Transportation (Caltrans) state-wide seismic retrofit of bridge expansion joints. The interchange was subjected to earthquake motion during the 1989 Loma Prieta earthquake and sustained minor damage in some of the concrete diaphragms which support the hinge restrainer forces [5]. Caltrans engineers, working together with their external consultants Imbsen and Associates, have recently completed a seismic retrofit design for portions of the interchange. The retrofit is primarily intended to fix inadequacies in many of the 1960`s vintage reinforced concrete elements which constitute the bridge superstructure and foundations.
Date: November 1996
Creator: McAllen, David B.; Gerhard, Michael A.; Trummer, David J. & Murray, Robert C.
Partner: UNT Libraries Government Documents Department

Tracer modeling in an urban environment

Description: The accurate simulation of the transport of a tracer released into an urban area requires sufficiently high model resolution to resolve buildings and urban street canyons. Within the authors' group a modeling effort has been underway to develop a model -- termed HIGRAD -- capable of simulating flow at the high spatial resolution required within the urban environment. HIGRAD uses state-of-the-art numerical techniques to accurately simulate the regions of strong shear found near edges of buildings. HIGRAD also employs a newly developed radiation package which in addition to standard shortwave and longwave heating/cooling effects can account for the shadowing effects of building complexes on the urban flow field. Idealized simulations have been conducted which clearly illustrate the role radiation plays in transport and dispersion in an urban setting. The authors have also modeled the flow of an inert tracer in a realistic, complex urban environment. Complex flow/building interactions were produced during the simulation and these interactions had a significant impact on the transport of the tracer.
Date: December 31, 1998
Creator: Reisner, J.M.; Smith, W.S.; Bossert, J.E. & Winterkamp, J.L.
Partner: UNT Libraries Government Documents Department

Two-lane traffic rules for cellular automata: A systematic approach

Description: Microscopic modeling of multi-lane traffic is usually done by applying heuristic lane changing rules, and often with unsatisfying results. Recently, a cellular automation model for two-lane traffic was able to overcome some of these problems and to produce a correct density inversion at densities somewhat below the maximum flow density. In this paper, the authors summarize different approaches to lane changing and their results, and propose a general scheme, according to which realistic lane changing rules can be developed. They test this scheme by applying it to several different lane changing rules, which, in spite of their differences, generate similar and realistic results. The authors thus conclude that, for producing realistic results, the logical structure of the lane changing rules, as proposed here, is at least as important as the microscopic details of the rules.
Date: November 5, 1997
Creator: Nagel, K.; Wolf, D.E.; Wagner, P. & Simon, P.
Partner: UNT Libraries Government Documents Department

Gelcasting Polycrystalline Alumina

Description: OSRAM SYLVANIA INC. is a major U.S. manufacturer of high-intensity lighting. Among its products is the Lumalux TM line of high-pressure sodium vapor arc lamps, which are used for industrial, highway, and street lighting. The key to the performance of these lamps is the polycrystalline alumina (PCA) tube that is used to contain the plasma that is formed in the electric arc. That plasma consists of ionized sodium, mercury, and xenon vapors. The key attributes of the PCA tubes are their transparency ({approximately}97% total transmittance in the visible), their refractoriness (inner wall temperature can reach l2OOC), and their chemical resistance (sodium and mercury vapor are extremely corrosive). The current efficiency of the lamps is very high, up to 100 initial lumens per watt. (Compare incandescent lamps 10-20 lumens per watt, fluorescent lamps 25-90 lumens per watt.)
Date: January 1, 2000
Creator: Janney, M.A.; Zuk, K.J. & Wei, G.C.
Partner: UNT Libraries Government Documents Department

Surface radiological investigations along State Highway 95, Lagoon Road, and Melton Valley Drive, Oak Ridge Reservation, Oak Ridge, Tennessee

Description: The surface radiological investigation along State Highway 95, Lagoon Road, and Melton Valley Drive at the Oak Ridge Reservation was conducted as part of the Oak Ridge National Laboratory Environmental Restoration Program Surveillance and Maintenance activities. This report was prepared to document results of the investigation and subsequent remedial actions. The report details surface gamma radiation levels including gamma anomalies; surface beta radiation levels including beta anomalies; results of analysis of soil, water, and vegetation samples and smear samples collected from paved surfaces; remediation activities conducted as a result of the survey; and recommendations for further corrective measures.
Date: August 1, 1995
Creator: Tiner, P.F.; Uziel, M.S.; Rice, D.E. & Williams, J.K.
Partner: UNT Libraries Government Documents Department

Advanced weigh-in-motion system for weighing vehicles at high speed

Description: A state-of-the-art, Advanced Weigh-In-Motion (WIM) system has been designed, installed, and tested on the west bound side of Interstate I-75/I-40 near the Knox County Weigh Station. The project is a Cooperative Research and Development Agreement (CRADA) between Oak Ridge National Laboratory (ORNL) and International Road Dynamics, Inc. (IRD) sponsored by the Office of Uranium Programs, Facility and Technology Management Division of the Department of Energy under CRADA No. ORNL95-0364. ORNL, IRD, the Federal Highway Administration, the Tennessee Department of Safety and the Tennessee Department of Transportation have developed a National High Speed WIM Test Facility for test and evaluation of high-speed WIM systems. The WIM system under evaluation includes a Single Load Cell WIM scale system supplied and installed by IRD. ORNL developed a stand-alone, custom data acquisition system, which acquires the raw signals from IRD`s in-ground single load cell transducers. Under a separate contract with the Federal Highway Administration, ORNL designed and constructed a laboratory scale house for data collection, analysis and algorithm development. An initial advanced weight-determining algorithm has been developed. The new advanced WIM system provides improved accuracy and can reduce overall system variability by up to 30% over the existing high accuracy commercial WIM system.
Date: February 1, 1998
Creator: Beshears, D.L.; Muhs, J.D. & Scudiere, M.B.
Partner: UNT Libraries Government Documents Department

Aggregate vehicle travel forecasting model

Description: This report describes a model for forecasting total US highway travel by all vehicle types, and its implementation in the form of a personal computer program. The model comprises a short-run, econometrically-based module for forecasting through the year 2000, as well as a structural, scenario-based longer term module for forecasting through 2030. The short-term module is driven primarily by economic variables. It includes a detailed vehicle stock model and permits the estimation of fuel use as well as vehicle travel. The longer-tenn module depends on demographic factors to a greater extent, but also on trends in key parameters such as vehicle load factors, and the dematerialization of GNP. Both passenger and freight vehicle movements are accounted for in both modules. The model has been implemented as a compiled program in the Fox-Pro database management system operating in the Windows environment.
Date: May 1, 1995
Creator: Greene, D.L.; Chin, Shih-Miao & Gibson, R.
Partner: UNT Libraries Government Documents Department

Estimating vehicle roadside encroachment frequency using accident prediction models

Description: The existing data to support the development of roadside encroachment- based accident models are extremely limited and largely outdated. Under the sponsorship of the Federal Highway Administration and Transportation Research Board, several roadside safety projects have attempted to address this issue by providing rather comprehensive data collection plans and conducting pilot data collection efforts. It is clear from the results of these studies that the required field data collection efforts will be expensive. Furthermore, the validity of any field collected encroachment data may be questionable because of the technical difficulty to distinguish intentional from unintentional encroachments. This paper proposes an alternative method for estimating the basic roadside encroachment data without actually field collecting them. The method is developed by exploring the probabilistic relationships between a roadside encroachment event and a run-off-the-road event With some mild assumptions, the method is capable of providing a wide range of basic encroachment data from conventional accident prediction models. To illustrate the concept and use of such a method, some basic encroachment data are estimated for rural two-lane undivided roads. In addition, the estimated encroachment data are compared with the existing collected data. The illustration shows that the method described in this paper can be a viable approach to estimating basic encroachment data without actually collecting them which can be very costly.
Date: July 1, 1996
Creator: Miaou, S.-P.
Partner: UNT Libraries Government Documents Department

Optimization-based Method for Automated Road Network Extraction

Description: Automated road information extraction has significant applicability in transportation. It provides a means for creating, maintaining, and updating transportation network databases that are needed for purposes ranging from traffic management to automated vehicle navigation and guidance. This paper is to review literature on the subject of road extraction and to describe a study of an optimization-based method for automated road network extraction.
Date: September 18, 2001
Creator: Xiong, D
Partner: UNT Libraries Government Documents Department

1995 Bird survey Foothills parkway section 8B National Park Service, Tennessee

Description: The Foothills Parkway Section 8B right-of-way (ROW) is a stretch of land between Pittman Center and Cosby, Tennessee that is approximately 14.2 miles long and 1,000 ft wide, with a considerably wider section on Webb Mountain. A breeding bird survey was conducted at selected sample points along the ROW. The intent of the survey was to identify bird communities, area sensitive species (birds dependent on extensive forest systems for all their needs) and endangered, threatened, federal candidate, and state `in need of management` species now using the ROW. The survey also provides baseline data to assess future habitat impacts as well as cumulative impacts of the project.
Date: May 1, 1996
Creator: Wade, M. C.; Giffen, N. R. & Wade, B. A.
Partner: UNT Libraries Government Documents Department

Analysis of automated highway system risks and uncertainties. Volume 5

Description: This volume describes a risk analysis performed to help identify important Automated Highway System (AHS) deployment uncertainties and quantify their effect on costs and benefits for a range of AHS deployment scenarios. The analysis identified a suite of key factors affecting vehicle and roadway costs, capacities and market penetrations for alternative AHS deployment scenarios. A systematic protocol was utilized for obtaining expert judgments of key factor uncertainties in the form of subjective probability percentile assessments. Based on these assessments, probability distributions on vehicle and roadway costs, capacity and market penetration were developed for the different scenarios. The cost/benefit risk methodology and analysis provide insights by showing how uncertainties in key factors translate into uncertainties in summary cost/benefit indices.
Date: October 1994
Creator: Sicherman, A.
Partner: UNT Libraries Government Documents Department

Registrations and vehicle miles of travel of light duty vehicles, 1985--1995

Description: To obtain vehicle registration data that consistently and accurately reflect the distinction between automobiles and light-duty trucks, Oak Ridge National Laboratory (ORNL) was asked by FHWA to estimate the current and historical vehicle registration numbers of automobiles and of other two-axle four-tire vehicles (i.e., light-duty trucks), and their associated travel. The term automobile is synonymous with passenger car. Passenger cars are defined as all sedans, coupes, and station wagons manufactured primarily for the purpose of carrying passengers. This includes taxicabs, rental cars, and ambulances and hearses on an automobile chassis. Light-duty trucks refer to all two-axle four-tire vehicles other than passenger cars. They include pickup trucks, panel trucks, delivery and passenger vans, and other vehicles such as campers, motor homes, ambulances on a truck chassis, hearses on a truck chassis, and carryalls. In this study, light-duty trucks include four major types: (1) pickup truck, (2) van, (3) sport utility vehicle, and (4) other 2-axle 4-tire truck. Specifically, this project re-estimates statistics that appeared in Tables MV-1 and MV-9 of the 1995 Highway Statistics. Given the complexity of the approach developed in this effort and the incompleteness and inconsistency of the state-submitted data, it is recommended that alternatives be considered by FHWA to obtain vehicle registration data. One alternative is the Polk`s NVPP data (via the US Department of Transportation`s annual subscription to Polk). The second alternative is to obtain raw registration files from individual states` Departments of Motor Vehicles and to decode individual VINs.
Date: February 1, 1998
Creator: Hu, P.S.; Davis, S.C. & Schmoyer, R.L.
Partner: UNT Libraries Government Documents Department

Clean Cities Award Winning Coalition: Chicago

Description: The Chicago area coalition marks its five-year anniversary in 1999 as a member of the Clean Cities Program. Their progress in the last five years has been remarkable as they advance the alternative fuel and vehicle markets, increase coalition membership, help support new alternative fuel vehicle (AFV) legislation, and educate fleet managers. The coalition boasts more than 90 stakeholders, including industry, government, environmental and academic organizations, and membership continues to grow. Thanks to dedicated coalition members' efforts, a variety of AFVs can be seen on Chicago's streets, including transit and school buses, taxicabs, sedans, vans, and trucks.
Date: May 19, 1999
Creator: Kaiser, ICF
Partner: UNT Libraries Government Documents Department

Clean Cities Award Winning Coalition: Salt Lake City

Description: Since its designation as a national Clean City in 1994, Salt Lake Clean Cities has put more than 2,600 alternative fuel vehicles (AFVs) on community streets. The 82 business, nonprofit, and government agencies that comprise the coalition are all dedicated to cleaning the air by reducing vehicle exhaust. Salt Lake Clean Cities has the third largest compressed natural gas and propane-refueling infrastructure in the country, with 98 locations available. They sponsor an annual ''Spring Soiree'' to increase public awareness about the program and educate the public about the benefits of alternative fuel and AFVs.
Date: May 20, 1999
Creator: Kaiser, ICF
Partner: UNT Libraries Government Documents Department

Transportation Energy Survey Data Book 1.1

Description: The transportation sector is the major consumer of oil in the United States. In 2000, the transportation sector's share of U.S. oil consumption was 68 percent (U.S. DOE/EIA, 2001a, Table 2.5, p. 33, Table 1.4, p.7). As a result, the transportation sector is one of the major producers of greenhouse gases. In 2000, the transportation sector accounted for one-third (33 percent) of carbon emissions (U.S. DOE/EIA, 2000b, Table 5, p.28). In comparison, the industrial sector accounted for 32 percent and residential and commercial sector for 35 percent of carbon emissions in 2000. Carbon emissions, together with other gases, constitute greenhouse gases that are believed to cause global warming. Because that the transportation sector is a major oil consumer and producer of greenhouse gases, the work of the Analytic Team of the Office of Transportation Technologies (OTT) focuses on two main objectives: (1) reduction of U.S. oil dependence and (2) reduction of carbon emissions from vehicles. There are two major factors that contribute to the problem of U.S. oil dependence. First, compared to the rest of the world, the United States does not have a large oil reserve. The United States accounts for only 9 percent of oil production (U.S. DOE/EIA, 2001c, Table 4.1C). In comparison, the Organization for Petroleum Exporting Countries (OPEC) produces 42 percent of oil, and the Persian Gulf accounts for 28 percent. (U.S. DOE/EIA, 2001c, Table 1.1A). More than half (54 percent) of oil consumed in the United States is imported (U.S. DOE/EIA, 2001a, Table 1.8, p. 15). Second, it is estimated that the world is approaching the point at which half of the total resources of conventional oil believed to exist on earth will have been used up (Birky et. al., 2001, p. 2). Given that the United States is highly dependent on imported oil and ...
Date: June 18, 2002
Creator: Gurikova, T
Partner: UNT Libraries Government Documents Department

Landslide remediation on Ohio State Route 83 using clean coal combustion by-products

Description: The disposal of flue gas desulfurization (FGD) by-products has become a major concern as issues of emission cleansing and landfill costs continue to rise. Laboratory tests conducted at the Ohio State University have shown that dry FGD by-products possess certain engineering properties that have proven desirable in a number of construction uses. As a follow on to the laboratory program, a field investigation into engineering uses of dry FGD wastes was initiated. In the present work, an FGD by-product was used to reconstruct the failed portion of a highway embankment. The construction process and the stability of the repaired embankment are examined.
Date: December 31, 1995
Creator: Payette, R.; Chen, Xi You; Wolfe, W. & Beeghly, J.
Partner: UNT Libraries Government Documents Department