see document / Master of Science

<p>This paper describes the development of simulation models for a variety of traffic flow scenarios. The major goal of the models was to evaluate the effects of driver characteristics and traffic composition on traffic flow. The five scenarios modeled and their respective objectives were as follows:</p> <p>1. Vehicles switching lanes to increase speed. Objectives were thruput and number of lane switches.</p> <p> 2. Vehicles merging into an adjacent lane. Objectives were distance traveled before merging and number of collisions during lane switching.</p> <p> 3. Vehicles switching from the left or right lane into the center lane. Objectives were number of collisions and number of new misses during lane switching.</p> <p> 4. Vehicles passing on a two-lane bidirectional road. Objective was number of collisions during passing. 5. Vehicles switching from the center lane to the left or right lane to avoid an impassible obstacle. Objectives were number of collisions during lane switching and number of collisions with obstacle.</p> <p> Various driver characteristics were implemented in the models. The concept of preoccupation/attentiveness was factored into the models through the use of varied reaction times. 0ther driver characteristics were incorporated in the models via the assignment of vehicle speed. The models provided for a wide variety of driver types. Examples are as follows:</p> <p> 1. Drivers in a hurry.</p> <p> 2. Tourists or drivers unfamiliar with the area.</p> <p> 3. Law-abiding drivers.</p> <p> 4. Aggressive and passive drivers.</p> <p> 5. Young, inexperienced drivers.</p> <p> 6. Tired truck drivers.</p> <p> The driver characteristics were varied via percentage allocations entered at run-time. The traffic composition for the models consisted of automobiles and multi-axle vehicles of fixed lengths. The percentages for each vehicle type were also entered at run-time.</p> <p> The scope and level of detail for each model was delineated with assumptions. General assumptions made included the following:</p> <p> 1. An autombile is 10 feet fong, a multi-axle vehicle is 30 feet long.</p> <p> 2. The width of a lane is such that only one vehicle can be accommodated at a time.</p> <p> 3. A vehicle is considered to be entirely in one lane or another.</p> <p> 4. A vehicle switches lanes instantaneously.</p> <p> 5. The reaction time of an attentive driver is normally distributed with a mean of .5; the reaction time of a preoccupied driver is normally distibuted with a mean of .7. Three standard deviations are included to ensure complete population coverage.</p> <p> 6. A collision between two vehicles results in the termination of the vehicle causing the collision: the other vehicle continues.</p> <p> Implementation of these models was performed using the student version of the simulation language GPSS/H. The models were validated. but not verified against their real world counterparts. Test results showed that select ctiver characteristics can affect traffic flow; however, the effect of traffic composition was relatively unshown.</p> / Master of Science

<p>Steel connection design is one area in structural steel design courses that is not always thoroughly addressed. This report attempts to address this area of steel design at a basic level. Its purpose is to be used as a teaching aid for a structural steel design course, and to familiarize students with connection design and its associated strength limit states.</p> <p> Limit states for steel connection design have been covered using both AISC ASD and LRFD Specifications. However, all included connection design examples used only LRFD limit states. Wherever possible all limit state calculations are accompanied by printouts from a knowledge-based expert system, CONXPRT.</p> <p> Typical building connection limit states are covered by way of an accompanying steel structure, which includes many of the connections, in order for students to receive an adequate grasp of both simple framing and moment connections. The purpose of this steel "sculpture" is to actively reinforce the students' understanding of the basic building connections seen in industry today.</p> / Master of Engineering

<p>The topic of this project is employee job descriptions within an athletic department. This project involves Virginia Polytechnic Institute and State University Athletic Department's top eight administrators. The job descriptions were reviewed and updated to ensure compliance with federal and state governments, university personnel office, and governing organizations.</p> <p> Since the ratification of Title VI many organizations have had to update their systems to comply with the Title VI legislation. In 1964, when Title VI of the Civil Rights Act was passed, many organizations found that they were not in compliance.</p> / Master of Science in Education

Master of Science

Master of Science

<p>The objective of this research project is to develop a computer assisted education system to enable users to effectively learn the Visual Simulation Environment (VSE), simulation and modeling. The vast amount and the relatively high complexity of the knowledge contained in the VSE, simulation, and modeling, dictate a need to provide an effective mechanism for assimilating the knowledge. This report describes the Learning Support System (LSS), a tool developed to present documents to users in an effective manner, thereby facilitating access to the knowledge contained within the documents. Text, graphics and animations are used within documents to support the learning process. The hierarchical organization of the information structure, the use of hypertext links, and search capabilities facilitate the efficient transfer of relevant information. The LSS thus incorporates features that contribute to an improved learning process. Usability tests across a wider spectrum of users would enable the LSS to be modified to meet the needs of the diverse user community. The LSS will be used in the Spring '95 Simulation classes to aid in the teaching of simulation and modeling. Feedback from users will shape the future enhancements to LSS. Future technology changes are expected to provide advantages for building on the LSS research project described herein. / Master of Science

The purpose of this project was to create guidelines of practice for college athletic directors in creating injury waivers for their departments. It is the complexity of the different issues concerning the waiver that ledSteve Horton, an Assistant Athletic Director at Virginia Tech to suggest the need for the development of standards for collegiate athletic programs in Virginia (Horton, 1993). However, it is possible for standards to be developed that can be used for any athletic department as long as the users are aware of the applicable laws in their own states. Creation of general guidelines will provide a tool which athletic departments can use in establishing their standard of care to the athletes. The establishment of tangible guidelines may make the use of injury waivers as a defense, more plausible in court / Master of Science

This paper presents a study of the Computer Aided Design (CAD) needs for the Facilities Engineering Division (PENGD) of NASA Langley Research Center. PENGD currently has many more projects than resources. Government cuts and reductions in personnel promise to make the situation worse. PENGD needs to increase the throughput of its existing staff while also decreasing the product cycle of a project. The existing design scenario with PC based CAD is used as a baseline to evaluate possible improvements and cost savings by implementing workstation based CAD with feature-based solid modeling. A detailed case study is used to illustrate and compare the differences in designing with AutoCAD1 and ProlEngineer. Equivalent hourly engineering rates are calculated for each system based on a four year life cycle. The results of the case study and engineering rates are used to determine the actual cost of designing with both CAD systems. A costlbenefit analysis is used to determine the cost effectiveness of continued use of PC based CAD with complex design projects versus the purchase and integration of workstation based CAD. My findings conclude that projects with any degree of uncertainty benefit from workstation based CAD. Solid modeling provides a mechanism for thorough study which reduces modifications, rework, and schedule delays. The associative database greatly reduces the amount of time required to create and update drawings. As uncertainty increases, the savings from using workstation based CAD over PC based CAD also increases. / Master of Engineering

Master of Science