Launching Facility Constraints on the Space Exploration Initiative
The Space Exploration Initiative (SEI) proposes large space programs such as a human mission to Mars and the establishment of a lunar base. These programs will require massive logistical...
Launch Facilities as Infrastructure
Many of the launch facilities in this country impose inefficiencies on launch service providers due to the way they have been constructed. To improve launch operation efficiency and to...
Using Simulation to Evaluate On-Orbit Construction Operations
As the NASA Space Exploration Initiative (SEI) program contemplates a permanent presence on both the Lunar and Martian soil, the necessity for On-Orbit Construction of the Earth-to-Lunar/Martian...
Studies Related to Aircraft/Runway Friction Performance
Gaining a better understanding of the many factors influencing the tire/runway friction interface is the aim of several ongoing NASA Langley research programs. Results from studies conducted...
Baggage System Implementation at DIA
BAE Automated Systems is currently under contract to supply the complete, Integrated Automated Baggage Handling System (IABHS) for the New Denver International Airport. The system represents...
Modeling 3-D Circulation Using the DSS Technique
The direct stress solution (DSS) technique allows a numerical internal mode solution for the vertical variation of shear stress, rather than velocity, in a three-dimensional circulation...
The Last Freeway
Ever since what's now known as the Pasadena Freeway was completed in 1940, Los Angeles has been synonymous with the freeway�first with the ease and speed of transport it represented...
Transportation Planning Requirements of the Federal Clean Air Act Amendments (CAAAs) of 1990: A Highway Perspective
The transportation community faces many challenges ahead, as it tries to meet the Nation's mobility needs, reduce congestion levels, and improve air quality. Traffic congestion is increasing...
Opportunities for Improved Transportation Planning
The approaches, technical procedures, and analytical methodologies utilized for urban transportation planning need to be improved if the intent of the 1990 amendments to the Clean Air...
Arizona's Metropolitan Travel Reduction Programs
This paper documents the short-term response to Arizona's metropolitan travel reduction programs. The Phoenix (Maricopa County) and Tucson (Pima County) programs were initiated in 1988....
Effectiveness of Implemented HOV Lane System
Individual carpool lanes have proven their worth on a case by case basis. Now, in California and across the country, systems of HOV lanes are being planned for urban areas dealing with...
Estimation of Travel Related Inputs to Air Quality Models
A major contribution to air pollution is vehicular travel, i.e., mobile sources. The estimation of pollutant emissions due to vehicular travel is a major task of air quality modeling....
VMT for Air Quality Purposes
This paper addresses VMT as one of the important parameters in air quality analysis. It covers three main topics: (1) The context in which VMT should be viewed as one parameter for measuring...
Generating Detailed Emissions Forecasts Using Regional Transportation Models: Current Capabilities and Issues
Mobile source emission estimates have long been calculated using composite emission factors (expressed as grams of emissions per mile) and estimates of vehicle-miles travelled. Techniques...
Laboratory Tests of Modal Emissions and Off-Cycle Corrections to FTP-75
The modeling of emissions from on-road mobile sources is an on-going process. Two broad topics which are currently under study are the evaluation of driving cycles and the development...
In-Use Emissions with Today's Closed-Loop Systems
Closed-loop emission control systems were adopted by most motor vehicle manufacturers on a wide-spread basis in model year 1981, in order to meet the 1981 and later Federal exhaust emission...
Characteristics of MOBILE4 and EMFAC7E Models
Several recent studies (e.g., Lawson et al., 1990; Ingalls, 1989) have indicated that the EPA and ARB vehicle emission factor models MOBILE4 and EMFAC7E underpredict in-use vehicle emission...
Reliability Analysis of Uncertain Systems Under Random Loadings
This study considers the reliability assessment of uncertain systems under random loadings. The fast integration method (Wen and Chen, 1987) in conjunction with a second order asymptotic...
Controlled Braking on Uneven Roads
The braking process of a passenger car may be influenced by a large number of variables relating to driver, vehicle, brake system, tire-road interaction and ambient conditions. Because...
A Selective MC Simulation Technique for Nonlinear Structural Reliability Assessment
A selective Monte Carlo simulation (MCS) procedure for the evaluation of the reliability of nonlinear structures subjected to dynamic random loading is presented. The proposed 'double...
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