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Full-Text Articles in Systems Engineering

Implementation And Demonstration Of A Multiple Model Adaptive Estimation Failure Detection System For The F-16, Peter K. Eide Dec 1994

Implementation And Demonstration Of A Multiple Model Adaptive Estimation Failure Detection System For The F-16, Peter K. Eide

Theses and Dissertations

A Multiple Model Adaptive Estimation (MMAE) algorithm is implemented with the fully nonlinear six-degree-of-motion, Simulation Rapid-Prototyping Facility (SRF) VISTA F-16 software simulation tool. The algorithm is demonstrated to be capable of identifying flight critical aircraft actuator and sensor failures at a low dynamic pressure (20,000 ft, .4 Mach). Research included single and dual complete failures. Tuning methods for accommodating model mismatch, including addition of discrete dynamics pseudonoise and continuous measurement pseudonoise, are discussed and demonstrated. Scalar residuals within each filter are also examined and characterized for possible use as an additional failure declaration voter. Robustness to sensor failures provided by …


Development Of A Knowledge-Based System For Wastewater Pipeline Rehabilitation, David Allen Reaves Oct 1994

Development Of A Knowledge-Based System For Wastewater Pipeline Rehabilitation, David Allen Reaves

Engineering Management & Systems Engineering Theses & Dissertations

The purpose of this thesis is to study and develop a knowledge-based system to make decisions for the rehabilitation of wastewater pipelines. Development includes justification for the use of an expert system, data acquisition from knowledge experts, program model development, model testing, implementation and future considerations including expansion. The model is developed and implemented using an expert system shell called XIPlus ®.

This knowledge-based system is designed specifically for the Navy Public Works Center Utilities Department at Norfolk Naval Base in Norfolk, Virginia for making decisions for the rehabilitation of the 50-year-old wastewater collection system. Recent sewer collapses and a …


A Functional Architecture For Automated Highway Traffic Planning, H.-S. Jacob Tsao Jul 1994

A Functional Architecture For Automated Highway Traffic Planning, H.-S. Jacob Tsao

Faculty Publications

In a fully automated Automated Highway System (AHS), the roadside control system and the vehicles themselves are responsible for moving the large number of vehicles safely and efficiently. Therefore, the task of operating an AHS is drastically different from and much more complex than its conventional counterpart. Resulting from a large number of design options, there exist many possible ways to operate an AHS. Each of these possible operating scenarios will support a different set of functions. A crucial task in AHS R&D is to evaluate and compare these potentially large number of different AHS operating scenarios with respect to …


Capacity Of Automated Highway Systems: Effect Of Platooning And Barriers, H.-S. Jacob Tsao, Randolph Hall, Bruce Hongola Feb 1994

Capacity Of Automated Highway Systems: Effect Of Platooning And Barriers, H.-S. Jacob Tsao, Randolph Hall, Bruce Hongola

Faculty Publications

The concept of Automated Highway Systems (AHS) is based on the belief that an appropriate integration of control and communication technologies placed on the vehicle and on the highway can lead to a large improvement in capacity and safety without requiring a significant amount of additional highway right-of-way. Stemming from this belief are various conceptual scenarios for vehicle/highway automation.An AHS consists of two major components: vehicle/highway automation technology and highway operating strategy. In this paper, we study the capacity of key AHS operating scenarios.


A Probabilistic Model For Avcs Longitudinal Collision/Safety Analysis, Jacob Tsao, Randolph Hall Jan 1994

A Probabilistic Model For Avcs Longitudinal Collision/Safety Analysis, Jacob Tsao, Randolph Hall

Faculty Publications

This paper develops a probabilistic model for analyzing longitudinal collision/safety between an abruptly decelerating vehicle and its immediate follower. The input parameters are the length of the gap between the two vehicles, their common speed prior to the failure, the reaction delay of the following vehicle and a bivariate distribution for the two deceleration rates. The output includes the probability of a collision and the probability distribution of the relative speed at collision time We use this model to compare the safety consequences associated with the platooning and “free-agent” longitudinal-separation rules. We also demonstrate that the free-agent rule implemented with …


Constraints On Initial Ahs Deployment And The Concept Definition Of A Shuttle Service For Ahs Debut, Jacob Tsao Jan 1994

Constraints On Initial Ahs Deployment And The Concept Definition Of A Shuttle Service For Ahs Debut, Jacob Tsao

Faculty Publications

Highway automation and its evolution involve a multitude of systems issues. Particularly important and difficult in defining a deployment sequence is the very first step, i.e. the first user service involving fully automated freeway driving. However, this importance and the difficulty imply that many factors may severely constrain the initial deployment. After discussing the paramount importance of initial AHS deployment, this paper points out major high-level issues and constraints. Any realistic deployment strategy must take into consideration gradual technology maturation, introduction of new driver role and diminishing conventional driver role for automated driving, high cost of early-generation automation-equipped vehicles, gradual …


Constraints On Initial Ahs Deployment And The Concept Definition Of A Shuttle Service For Ahs Debut, Jacob Tsao Jan 1994

Constraints On Initial Ahs Deployment And The Concept Definition Of A Shuttle Service For Ahs Debut, Jacob Tsao

H.-S. Jacob Tsao

Highway automation and its evolution involve a multitude of systems issues. Particularly important and difficult in defining a deployment sequence is the very first step, i.e. the first user service involving fully automated freeway driving. However, this importance and the difficulty imply that many factors may severely constrain the initial deployment. After discussing the paramount importance of initial AHS deployment, this paper points out major high-level issues and constraints. Any realistic deployment strategy must take into consideration gradual technology maturation, introduction of new driver role and diminishing conventional driver role for automated driving, high cost of early-generation automation-equipped vehicles, gradual …


A Probabilistic Model For Avcs Longitudinal Collision/Safety Analysis, Jacob Tsao, Randolph Hall Jan 1994

A Probabilistic Model For Avcs Longitudinal Collision/Safety Analysis, Jacob Tsao, Randolph Hall

H.-S. Jacob Tsao

This paper develops a probabilistic model for analyzing longitudinal collision/safety between an abruptly decelerating vehicle and its immediate follower. The input parameters are the length of the gap between the two vehicles, their common speed prior to the failure, the reaction delay of the following vehicle and a bivariate distribution for the two deceleration rates. The output includes the probability of a collision and the probability distribution of the relative speed at collision time We use this model to compare the safety consequences associated with the platooning and “free-agent” longitudinal-separation rules. We also demonstrate that the free-agent rule implemented with …


A Study Of Similarity And Analogical Decision-Making In Collaborative Design, Christopher Edward Weeks Jan 1994

A Study Of Similarity And Analogical Decision-Making In Collaborative Design, Christopher Edward Weeks

Engineering Management & Systems Engineering Theses & Dissertations

The purpose of this study is to investigate the role of similarity and analogy in design communication and propose a descriptive representation of the analogical decision-making process in the context of engineering design. It is proposed that social, cultural, and contextual knowledge are brought to bear on statements of need in the form of analogy as a means to elicit and evince potential design solutions. A goal of this study is to identify communicative behaviors, representing process variables of analogical decision-making, that can be used to describe how design information is represented, manipulated, and conveyed in a collaborative design effort. …


Guidelines For Ensuring Software Supportability In Systems Developed Under The Integrated Weapon System Management Concept, Forrest F. Butts Iii, Anthony C. Johndro Dec 1993

Guidelines For Ensuring Software Supportability In Systems Developed Under The Integrated Weapon System Management Concept, Forrest F. Butts Iii, Anthony C. Johndro

Theses and Dissertations

This thesis studied the software maintenance planning and practices of the pilot Integrated Weapon System Management IWSM programs. Before IWSM, a System Program Office SPO acquired an Air Force weapon system then passed it to an Air Logistics Center ALC for follow-on support. The ALC was forced to maintain the software despite its questionable maintainability. The SPO de- emphasized maintainability because maintenance was an ALC responsibility and building maintainable software increased development costs and lengthened schedules. The IWSM philosophy closes the gap between development and maintenance. A System Program Director SPD, who oversees both system development and maintenance, has an …


A Multivariate Quality Control Approach For Automated Manufacturing Systems, Hisham Naim Ashur Jul 1993

A Multivariate Quality Control Approach For Automated Manufacturing Systems, Hisham Naim Ashur

Engineering Management & Systems Engineering Theses & Dissertations

In today's competitive manufacturing environment, effective and practical statistical quality control approaches are essential. A successful process control approach needs to provide on line real time monitoring of quality related characteristics.

No longer acceptable is an approach that analyzes quality related data only after the product is produced. A statistical process control approach that monitors the process during production and that reports trouble spots before bad products are made is necessary in an automated manufacturing environment.

An automated manufacturing environment is characterized by high volume production runs and short production cycles. Traditional statistical process control approaches are not capable of …


Development Of A Knowledge Based System For Wastewater Pipeline Failure Risk Assessment, Adam Mayanzani Ngaliga Jul 1993

Development Of A Knowledge Based System For Wastewater Pipeline Failure Risk Assessment, Adam Mayanzani Ngaliga

Engineering Management & Systems Engineering Theses & Dissertations

The purpose of this thesis was to study and analyze the wastewater pipeline failure risk assessment process, and then design and develop an effective and efficient wastewater pipeline risk assessment tool for the Hampton Roads Sanitation District, in Virginia, U.S.A. A knowledge based system was developed using an expert system building shell (Xi-Plus).

The system design is based on the knowledge elicited from the experts and literature in sanitary pipeline failure risk evaluation. The knowledge base contains both heuristics and procedural rules. The system interprets the information provided by the user and reasons from that information to reach conclusions on …


A Probabilistic Model And A Software Tool For Avcs Longitudinal Collision/Safety Analysis, H.-S. Jacob Tsao, Randolph Hall Jun 1993

A Probabilistic Model And A Software Tool For Avcs Longitudinal Collision/Safety Analysis, H.-S. Jacob Tsao, Randolph Hall

Faculty Publications

This paper develops a probabilistic model and a software tool for analyzing longitudinal collision/safety between two automated vehicles. The input parameters are the length of the gap between the two vehicles, the common speed prior to the failure, the reaction delay of the following vehicle and a bivariate pint distribution of the deceleration rates of the two vehicles. The output includes the probability of a collision and also the probability distribution of the relative speed at collision time.We will use this model to compare the safety consequences associated with the platooning and "free-agent" vehicle-following rules. We will also demonstrate that …


Reliability Trend Analyses With Statistical Confidence Limits Using The Luke Reliability Trend Chart, Stephen R. Luke Jan 1993

Reliability Trend Analyses With Statistical Confidence Limits Using The Luke Reliability Trend Chart, Stephen R. Luke

Engineering Management & Systems Engineering Theses & Dissertations

In electronic systems, it is interesting to understand exactly how the reliability is changing with time. Dynamic performance changes when a system passes from infant mortality stage into useful life phase and when the system passes from useful life phase into wearout phase. Dynamic performance also changes when the system is redesigned or when the system is acted on by a number of other outside forces such as a change in maintenance policy, escalation of alignment problems, or a change in training program. It is important to know when a system is changing dynamically in order to assess design, policy …


Multidimensional Approach To Implementation Of Continuous Process Improvement Utilizing Small Run Analysis In A Shipyard Environment, Paul Ray Hollandsworth Jan 1993

Multidimensional Approach To Implementation Of Continuous Process Improvement Utilizing Small Run Analysis In A Shipyard Environment, Paul Ray Hollandsworth

Engineering Management & Systems Engineering Theses & Dissertations

Nationally, both public and private shipyards are experiencing a high rework rate (over 40%) in the fabrication of plug connectors used for electronic systems onboard Navy vessels. The shipyard's survival depends on acquiring the elements necessary to maintain a major industry in a position of continuous improvement that produces a better product than their competitors, at less cost, in a safe manner, and on schedule.

This research addresses the complex problem of how to introduce quality control methodologies within a job shop environment that assists in identifying variables that influence the rework rate of plug fabrication process over a four …


Domain Limitations And Interface Requirements For Expert Developed Knowledge Based Systems, Bernard Lee Lewis Oct 1991

Domain Limitations And Interface Requirements For Expert Developed Knowledge Based Systems, Bernard Lee Lewis

Engineering Management & Systems Engineering Theses & Dissertations

The expanded use of graphical, case-based and object oriented techniques in expert systems creation has made it more practical for domain experts to develop their own applications. This thesis focuses on the elements necessary in an expert/developer interface and looks at various forms and techniques that exemplify such an approach. The spreadsheet metaphor is used for an interface or managed set of interfaces that a domain expert can use in building his own expert system or prototype. criteria are established for such interfaces and recent commercial offerings that make expert-created knowledge-bases more practical are reviewed for techniques that qualify. Approaches …


A Robust Approach To Human-Computer Interface Design Using The Taguchi Method, Billie Mitchell Reed Jul 1991

A Robust Approach To Human-Computer Interface Design Using The Taguchi Method, Billie Mitchell Reed

Engineering Management & Systems Engineering Theses & Dissertations

The application of Dr. Genichi Taguchi's approach for design optimization, called Robust Design, to the design of human-computer interface software is investigated. The Taguchi Method is used to select a near optimum set of interface design alternatives to improve user acceptance of the resulting interface software product with minimum sensitivity to uncontrollable noise caused by human behavioral characteristics.

Design alternatives for interaction with personal micro-computers are identified. Several important and representative alternatives are chosen as design parameters for the Taguchi matrix experiment. A noise field with three human behavioral characteristics as noise factors were chosen as a representative noise array. …


An Unsolicited Sociotechnical Intervention In A Public System: A Participatory Action Research Approach, Ely Alfred Dorsey Jr. Jan 1991

An Unsolicited Sociotechnical Intervention In A Public System: A Participatory Action Research Approach, Ely Alfred Dorsey Jr.

Engineering Management & Systems Engineering Theses & Dissertations

This research concerns itself with Participatory Action Research in a hostile setting. The thrust is a sociotechnical one, with the intent being to enhance the capacity of the Wallop Public School System, Wallop, USA, to address its problem of racial disparate treatment of Black children. The potential for Organizational Learning among the school system's senior staff is studied. Some new theory about such hostile interventions is proposed. Also discussed are questions about reliability and construct validity within the context of the multiple role playing that an interventionist has in this setting. The role of the press is reflected in the …


Information Technology And Wealth: Cybernetics, History And Economics, Elin Whitney-Smith Jan 1991

Information Technology And Wealth: Cybernetics, History And Economics, Elin Whitney-Smith

Engineering Management & Systems Engineering Theses & Dissertations

Capitalism developed where and when it did because there was high information access. There was high information access because of a major advance in information technology--the press. Where the technology was not controlled by the "powers that be" there was economic growth and a shift in the entire social structure. Where it was controlled there was no structural change and there was economic ruin. The development of capitalism is a major step change in economic growth. It is also a major change in the way people organize themselves into groups.

Major step changes in the growth and in the organization …


Relational Database Applications In Manufacturing System Design., Elizabeth C. Scheyder Dec 1989

Relational Database Applications In Manufacturing System Design., Elizabeth C. Scheyder

Elizabeth C Scheyder

Relational databases can be implemented as an effective design tool during the Preliminary and Final Engineering phases of manufacturing system design projects. The use of a hierarchical relational database structure will be shown to enhance system development, handling detailed information about electrical, mechanical, chemical or other parameters of system components and their applications. Holding such information in a central database structure as it becomes available maximizes its accessibility and coordinates communication between disciplines involved in the project. This enables calculations to be automated, ensures data integrity, and minimizes redundant compilation and typing of data. The ability to interface with a …


Polynomial Approximations To Mooring Forces In Equations Of Low-Frequency Vessel Motions, Bohdan W. Oppenheim, P. A. Wilson Mar 1982

Polynomial Approximations To Mooring Forces In Equations Of Low-Frequency Vessel Motions, Bohdan W. Oppenheim, P. A. Wilson

Systems Engineering Faculty Works

Multivariate polynomial approximations are considered to the coupled nonlinear mooring forces acting on a vessel moored with multileg moorings. The objective is to yield explicit forms of equations of the low-frequency vessel motions, since the exact mooring forces are known numerically only. Such forms could then be used for analytical solutions of the equations of motion. It is shown that the polynomials lack sufficient generality and accuracy for this purpose, and hence solution of the problem can be considered only by the exact method.


Low-Frequency Dynamics Of Moored Vessels, Bohdan W. Oppenheim, P. A. Wilson Jan 1982

Low-Frequency Dynamics Of Moored Vessels, Bohdan W. Oppenheim, P. A. Wilson

Systems Engineering Faculty Works

Three complete theories of the low-frequency dynamics of ships and disks moored with multileg mooring systems in deep water are derived, evaluated, and computerized. One theory is nonlinear; it includes the effects of cubic damping, nonlinear mooring forces and the excitation-yaw motion feedback, and it is handled by simulation. It yields random, regular and transient records, probabilities and statistics, exact and linearized transfer functions, and spectra of responses. The second theory is linear, solved in the frequency domain. The third is a static theory, which is a by-product of the linear one. Mooring lines of arbitrary compositions are considered.


Static 2-D Solution Of A Mooring Line Of Arbitrary Composition In The Vertical And Horizontal Operating Modes, Bohdan W. Oppenheim Jan 1982

Static 2-D Solution Of A Mooring Line Of Arbitrary Composition In The Vertical And Horizontal Operating Modes, Bohdan W. Oppenheim

Systems Engineering Faculty Works

A theoretical static solution is reported for a two-dimensional mooring line having an arbitrary multi-segment composition of wires, chains, synthetic ropes and buoys. The segments can be buoyant, neutrally buoyant or heavier than water, and they can be nonlinearly stretchable. The buoys can be of constant positive and negative buoyancy, thus representing submerged buoys and hung weights. A mooring line can operate in the 'horizontal' or slack mode, and in the 'vertical' or 'tension-moor' mode. In the former cese, a surface-floating 'spring-buoy' is allowed, as well as a linear slope of the sea bottom at the anchor.


The Biology Instrument For The Viking Mars Mission, Frederick S. Brown, H.E. Adelson, M.C. Chapman, O.W. Clausen, A.J. Cole, J.T. Cragin, R.J. Day, C.H. Debenham, R.E. Fortney, R.I. Gilje, D.W. Harvey, J.L. Kropp, S.J. Loer, J.L. Logan, Jr., W.D. Potter, G.T. Rosniak Jan 1978

The Biology Instrument For The Viking Mars Mission, Frederick S. Brown, H.E. Adelson, M.C. Chapman, O.W. Clausen, A.J. Cole, J.T. Cragin, R.J. Day, C.H. Debenham, R.E. Fortney, R.I. Gilje, D.W. Harvey, J.L. Kropp, S.J. Loer, J.L. Logan, Jr., W.D. Potter, G.T. Rosniak

Systems Engineering Faculty Works

Two Viking spacecraft have successfully soft landed on the surface of Mars. Each carries, along with other scientific instruments, one biology laboratory with three different experiments designed to search for evidence of living microorganisms in material sampled from the Martian surface. This 15.5-kg biology instrument which occupies a volume of almost 28.3 dm3 is the first to carry out an in situ search for extraterrestrial life on a planet. The three experiments are called the pyrolytic release, labeled release, and gas exchange. The pyrolytic release experiment has the capability to measure the fixation of carbon dioxide or carbon monoxide into …


Efficiency Of Sprinkler Irrigation Systems, T C. Calder Jan 1976

Efficiency Of Sprinkler Irrigation Systems, T C. Calder

Journal of the Department of Agriculture, Western Australia, Series 4

Shallow-rooted vegetable crops growing on sandy soils in hot, often windy summer weather, pose a difficult watering problem for most Western Australian vegetable growers.

Irregularities in wetting patterns are common. Wind effects are seldom taken into account in system design. The increasing popularity of knocker-type sprinklers makes these considerations particularily important.


Eight Tractors In The 35-45 H.P. Class. Part 1, W F. Baillie, G. H. Vasey Jan 1967

Eight Tractors In The 35-45 H.P. Class. Part 1, W F. Baillie, G. H. Vasey

Journal of the Department of Agriculture, Western Australia, Series 4

Summary report of tests on tractors in the 35-45 h.p. class by the Australian Tractor Testing Committee, based on Tractor Tests Nos. 38 to 45. Part 1


Development Of Detection And Tracking Systems For Autonomous Vehicles Using Machine Learning, Tyler Ward Apr 203

Development Of Detection And Tracking Systems For Autonomous Vehicles Using Machine Learning, Tyler Ward

Morehead State Theses and Dissertations

A thesis presented to the faculty of the Elmer R. Smith College of Business and Technology at Morehead State University in partial fulfillment of the requirements for the degree of Master of Science by Tyler Ward April 25, 2023.