Engineering Commons^™

A Comparison Of The Disaster™ Scheduling Software With A Simultaneous Scheduling Algorithm For Minimizing Maximum Tardiness In Job Shops, Barak J. Carlson, Christopher A. Lettiere

Theses and Dissertations

The Theory of Constraints (TOC) is the foundation for a computerized scheduling system called DISASTER. Although this system has proven successful in many manufacturing settings, it has potential limitations due to the sequential heuristic process by which it schedules constraints. The objective of this thesis was to determine the extent to which these limitations impact the due date performance of schedules created by DISASTER. This objective was addressed by developing an algorithm to simultaneously schedule multiple constraints in a job shop environment and provide the optimal schedule for minimized maximum tardiness. This algorithm was used to obtain solutions for a …

An Analysis Of The Effectiveness Of The Air Force Drug Testing Program And Four Potential Modifications, Thomas R. Doster, Hubert A. Ross

Theses and Dissertations

This study evaluated the 1992 USAF Drug Testing Program and potential improvements, based on the number of drug users detected, cost, and legal issues. Four potential improvements were examined: (1) increasing the annual amount of random urinalysis; (2) increasing the proportion of commander-directed testing; (3) using a weighted selection technique, and (4) replacing urinalysis with hair testing. For each improvement, the researchers used test and survey results to estimate the number of drug users detected, a cost formula to estimate any changes in cost, and interviews with legal experts to identify any legal issues associated with implementing the modification. Researchers …

Benchmark Production Scheduling Problems For Job Shops With Interactive Constraints, Stewart W. James, Bruno A. Mediate Jr.

Theses and Dissertations

United States Air Force (USAF) depots have expressed interest in utilizing DISASTER production scheduling software to schedule their maintenance operations. DISASTER attempts to increase system throughput by building effective schedules for system, constraint resources. However, when a system contains multiple, interactive constraints, DISASTER builds the constraint schedules one at a time. Since each successive schedule must adhere to timing restrictions imposed by previous constraint schedules, the quality of the schedules produced by DISASTER is dependent upon the sequence in which the constraints are scheduled. This thesis first developed a set of benchmark problems which provide a diversity of scheduling scenarios. …

An Investigation Of Integrated Product Development Implementation Issues: A Case Study Of Bosma Machine And Tool Corp, F. Paul Khuri, Howard M. Plevyak Jr.

Theses and Dissertations

This thesis investigated Integrated Product Development (IPD) implementation issues. Research emphasis focused on teams used in IPD, particularly self-directed work teams (SDWTs). The areas addressed in the study were: Work Environment, Team Organization, Training and Education, Group Dynamics and Communication, Motivation, Rewards and Incentives, Measurements, and Contracts. Data was collected using interviews and presented as a case study. The most significant findings on work environment were that the organization's leadership should commit to the teaming idea and sell it to the organization's members. Teams should be organized by choosing members carefully and defining all roles. Personnel should be trained in …

An Independent Evaluation Of Information Systems Support Of The Joint Forces Air Component Commander Concept Of Operations, Gregory R. Kincaid, Richard A. Poligala

Theses and Dissertations

This study examines automated Air Tasking Order (ATO) generation and dissemination under the Joint Forces Air Component Commander (JFACC) concept, focusing on an evaluation of information systems support given the differing service philosophies concerning control of tactical air assets. Current Department of Defense doctrine identifies the Contingency Tactical Air Control System Automated System (CTAPS) as the standard automated system for Theater Battle Management planning for the JFACC. To achieve service interoperability, the doctrine requires the use of CTAPS for ATO generation and dissemination when joint operations are conducted under the JFACC concept. A problem arises in that CTAPS is developed …

Scheduling A Medium-Sized Manufacturing Shop: A Simulation Study, Daniel J. Mcfeely

Theses and Dissertations

This study examined the application of simple-to-use, low cost scheduling methods to the operating environment of a medium-sized manufacturing shop. Computer simulation was used to evaluate eighteen different scheduling algorithms, each the result of the combination of a loading and a sequencing rule; due date setting was not considered since due dates are exogenously set. The loading rules investigated were Minimum Machine Required, Lowest Average WIP, and Lowest Average Aggregate Priority Level. The sequencing rules investigated were Priority, EDD, FIS, SPT, Slack, and Slack Ratio. The scheduling algorithms were evaluated against performance measures of mean tardiness, mean flowtime, mean percentage …

An Analysis Of The Performance-Risk Trade-Off In Source Selection Decision Making, Richard G. Pierce, Jeffrey E. Wainwright

Theses and Dissertations

Each year the Air Force awards weapon system contracts worth billions of dollars using the source selection process. In the source selection, performance and risk assessments are evaluated to determine the best proposal; the proposal that gives the best overall value. The purpose of this research was to investigate the performance/risk trade-off in the source selection decision making process. The study also examined the effect individual risk propensities and the nature of item being evaluated have on the performance/risk trade-off decisions. Air Force acquisition personnel stationed at Aeronautical Systems Center, Wright-Patterson AFB, OH, who had participated in a source selection …

An Investigation Of Integrated Product Development Teams Of The F-22 Program, Gary F. Wagner, Randall L. White

Theses and Dissertations

This study investigated Integrated Product Development (IPD) at the F-22 System Program Office (SPO). A literature review revealed the key IPD characteristics of organizational structure, communication, intense up-front planning, training, integrated management tools, and lessons learned. The research method was twenty-two personal interviews of SPO subjects selected from four IPD teams, the front office, and functional support divisions. Key findings included an emphasis on up-front planning to establish an organizational and contractual structure which empowered workers to develop their products. Also, constant communication with all other functions and teams was stressed while training was primarily done while transitioning to IPD. …

Transition Mechanisms Of Two Interacting Dx Centers In N-Type Algaas Using Reverse-Bias Deep Level Transient Spectroscopy And Temperature-Dependent Pulse-Width Reverse-Bias Deep Level Transient Spectroscopy Methods, C. W. Wang, Cheng-Hsiao Wu

Electrical and Computer Engineering Faculty Research & Creative Works

The reverse-bias pulsed deep level transient spectroscopy (RDLTS) and a new temperature-dependent pulse-width RDLTS (TDP RDLTS) technique are reported to study the electric-field effect on carrier emission rates and the direct interaction between double DX centers recently detected in the Se:Al_0.6Ga_0.4As N confinement layer of the AlGaAs/GaAs single-quantum-well laser diodes. Traditional RDLTS measurements, with constant pulse width t_p, prove that the two DX centers, Et₁ and Et₂, have strong direct emission interaction. Furthermore, the new TDP-RDLTS technique enables one to evaluate this direct transition time constant. Possible mechanisms for this interstate …

Analysis Of Alcohol And Speed Related Traffic Accidents In Fayette County, Kenneth R. Agent

Kentucky Transportation Center Research Report

One objective of this study was to update the statistics related to alcohol-related accidents and arrests In Fayette County. The second objective was to include an analysis of speed-related accidents and citations.

The number of alcohol-related accidents in Fayette County has decreased over the past several years. The number of speed-related accidents has remained relatively constant Differences between the characteristics of all accidents and alcohol and speed-related accidents were noted. For example, there were higher percentages of alcohol and speed-related accidents involving a fixed object. Differences in driver characteristics, such as the high percentage of drivers in the 16 to …

Analysis Of Traffic Accident Data In Kentucky (1988-1992), Kenneth R. Agent, Jerry G. Pigman

Kentucky Transportation Center Research Report

This report includes an analysis of traffic accident data in Kentucky tor the years of 1988-1992. A primary objective of this study was to determine average accident statistics tor Kentucky highways. Average and critical numbers and rates at accidents were calculated for various types of highways in rural and urban areas. These data can be used in Kentucky's procedure to identify locations that have abnormal rates or numbers of accidents.

Another objective of this study was to provide data which can be used in the preparation of the problem identification portion of Kentucky's Annual Highway Safety Plan. County and city …

Evaluation Of The Lexington-Fayette County Safety Belt Ordinance, Kenneth R. Agent

Kentucky Transportation Center Research Report

A mandatory safety belt ordinance was enacted in Fayette County with an effective date of July 1, 1990. One objective of this study was to conduct usage surveys after the ordinance had been in effect for approximately three years. This would allow comparisons to be made of safety belt usage before and immediately after the effective date of the ordinance to that found a substantial time period after enactment of the ordinance. A second objective of the study was to compere accident data before and after the ordinance became effective. The would allow an analysis of the effect the ordinance …

Bs News

Building Services Engineering

No abstract provided.

An Exploratory Survey Of Methods Used To Develop Measures Of Performance, Kenneth L. Hamner, Charles A. Lafleur

Theses and Dissertations

Nonmanufacturing organizations are being challenged to provide high- quality products and services to their customers, with an emphasis on continuous process improvement. Measures of performance, referred to as metrics, can be used to foster process improvement. The application of performance measurement to nonmanufacturing processes can be very difficult. This research explored methods used to develop metrics in nonmanufacturing Organizations. Several methods were formally defined in the literature, and the researchers used a two- step screening process to determine the OMB Generic Method was most likely to produce high-quality metrics. The OMB Generic Method was then used to develop metrics. A …

1993 Safety Belt Usage Survey And Evaluation Of Effectiveness In Kentucky, Kenneth R. Agent

Kentucky Transportation Center Research Report

The objective of the survey was to establish 1993 safety belt and child safety seat usage rates in Kentucky. Data were collected at 100 sites and combined based on vehicle miles travelled for a given type of highway, rural or urban location, and county population category. Also included in this report is an analysis of accident records evaluating the effectiveness of safety belts.

Statewide usage rates were 42 percent for drivers and front-seat passengers (over 19 years of age) and 61 percent for children under four years of age (front and rear seats). Driver usage rates increased in 1993 compared …

Dependence Of Binary Encounter Electron Production On The Charge State Of The Recoil Ion, Jee-Ching Wang, Ronald E. Olson, H. Wolf, J. Shinpaugh, W. Wolff, H. Schmidt Böcking

Chemical and Biochemical Engineering Faculty Research & Creative Works

We study the dependence of the production of binary encounter electrons on the charge state of recoil ions for 2.4 MeV u^-l Xe²¹⁺ on He and Ar. Doubly differential cross sections of electron emission are calculated with the ncrMC method. We find that the contributions to the binary electron cross section from various recoil ion charge states reach a maximum near Ar⁵⁺ for the Ar target. In the case of the He target; double ionization dominates over single ionization for alt ejected electron energies above 100 eV. However, an unexpected local drop of double ionization in the …

Transient Flowmeter Calibration Facility, Paul J. Lefebvre, William W. Durgin

Office of the Provost Scholarship

An apparatus for defining the free surface of a moving column of a fluid in a vertical pipe to enhance the accuracy of measurements of transient rate of flow of the fluid using electromagnetic flowmeter is described. It provides a neutrally buoyant plug which stays in contact with the free surface of the column of the fluid at all times and thus defines the free surface of the fluid moving in the vertical pipe accurately and reduces the oscillations of the free surface of the fluid.

Ccfss Technical Bulletin August 1993, Wei-Wen Yu Center For Cold-Formed Steel Structures

CCFSS Technical Bulletins (1993 - 2020)

No abstract provided.

Advanced Aeronatics Design: Project Based Engineering Education At Wpi, D. J. Olinger, William W. Durgin, Andreas N. Alexandrou

Office of the Provost Scholarship

One element of WPI's project-based curriculum is its interdisciplinary Advanced Aeronautics Design Program. Students participating in the program are involved in the design, construction, and flight testing of non-traditional aircraft such as an ultralight solar-powered vehicle, microwave-powered long endurance aircraft, or a flying oblique wing. The WPI project philosophy and character are described and illustrated using examples from the AAD program.

Acuta Enews August 1993, Vol. 22, No. 8

ACUTA Newsletters

In This Issue

Interview with Luther Robb

President's Message

Paradigms & Paradoxes

Total Quality Management

Super Schools

Win-Win Relationships

21st Century Technology

Executive Director's Message

Characterization Of A Resistive Half Plane Over A Resistive Sheet, John R. Natzke, John L. Volakis

Faculty Publications - Department of Electrical Engineering and Computer Science

The diffraction of a resistive half plane over a planar resistive sheet under plane wave illum1ination is determined via the dual integral equation method (a variation of the Wiener-Hopf method). The solution is obtained upon splitting the associated Wiener-Hopf functions via a numerically efficient routine. Based on the derived exact half plane dliffraction coefficient, a simplified equivalent model of the structure is developed when the separation of the half plane and resistive plane is on the order of a tenth of a wavelength or less. The model preserves the geometrical optics field of the original structure for all angles and …

Electric Fields Of An H-Plane Tapered Iris, John R. Natzke, T. Koryu Ishii

Faculty Publications - Department of Electrical Engineering and Computer Science

Microwave electric fields of an X -band H -plane tapered iris are calculated and plotted using the moment method for the first time. The moment method results are compared with previously obtained experimental measurements and numerical results based on an equivalent circuit approach, giving confirmation that the tapered iris is both a reciprocal and asymmetrical network. The moment method results now reveal that the asymmetry stems from the asymmetry in the phase of the input and output voltage reflection coefficients, their magnitudes being equal.

Electronic Simulation Of The Temporal Characteristics Of Photon Memory Echoes And Some Related Applications, Yuwen Kuo, Monish Ranjan Chatterjee

Electrical and Computer Engineering Faculty Publications

The characteristics of nonlinear photon memory echoes are investigated by means of SPICE simulations using equivalent resonator ensembles. By developing implicit nonlinear circuit models in the memory echo domain, the triple product formalism of electronic holography, involving correlation and convolution, is tested for the storage and recall of arbitrary signals and/or data bit streams in both time-inverted and nontime-inverted modes. Furthermore, a few specific optical data processing applications are also simulated in which the mixed binary multiplication of two or more binary bit streams is achieved.

Higher order products, optical pattern recognition, and other possible applications are also discussed. It …

Ccfss News August 1993, Wei-Wen Yu Center For Cold-Formed Steel Structures

CCFSS Newsletters (1999 - 2008)

No abstract provided.

Incorporation Of Traffic Collision Alert System (Tcas) Advisories On Heads-Up Displays: Enhanced Pilot Response, Hamadeh A. Nureddine

Master's Theses - Daytona Beach

This study evaluated the effects that heads-up mounted TCAS displays had on pilot response and workload. Pilot response was evaluated by: (a) response time to a traffic advisory, and (b) number of missed traffic alerts. Workload assessment was accomplished in accordance with NASA's Task Load Index (TLX). Subjects were all licensed pilots with a minimum of a private pilot license and an instrument rating. A total of 32 subjects were randomly assigned to experimental and control groups utilizing HUD-mounted, and conventional, TCAS displays respectively. Performance data was collected during computer-simulated flights, while subjective workload levels were reported at the end. …

An Econometric Analysis Of The Nw/Klm Corporate Alliance, S. Koo Boon

Master's Theses - Daytona Beach

This thesis investigates whether a corporate alliance between international air carriers is beneficial, considering the changes in the global air transport system. Dividing the research method into three phases, the author first lists and identifies the recent changes in world air transport trends. Then, the author defines the different types of alliances and studies the advantages and disadvantages of these corporate alliances. Finally, a multiple regression analysis is performed using the KLM/Northwest Airlines alliance as a case analysis.

Networking Your Cd-Roms: A Texas Tale, Margaret Sylvia

Faculty Publications

Installation of a CD-ROM network at St. Mary's University Academic Library created a revolution in the way students and faculty do research.

Proposed Smoothing Technique To Avoid Numerical Instabilities In A Hydrodynamic Numerical Model, Thomas P. Abraham

Electronic Theses and Dissertations

Despite every effort being made to produce a completely problem-free computational model, no breakthrough has yet been made. When a numerical model is used to solve a real world problem, there is a tendency for the non-physical spurious waves to creep in. If these waves are not checked, they can lead to serious instability problems. Once these waves are removed, the model should be able to simulate physical phenomenon like circulation, separation, flow reversal in the vertical plane, mixing/transport, convection/diffusion, etc.

When a numerical mode] is made to run for a certain period of time, node-to-node oscillations may arise and …

Analysis Of Sandwich Plates Subjected To Blast Loading, Vijay Prasad Bulla

Masters Theses

A dynamic analysis is presented for the bending response of square sandwich plates with isotropic core and facings under blast type pressure. The maximum central deflections of simply supported plates under static and dynamic loadings are compared for various thicknesses and elastic moduli. The deviation of the thick sandwich plate results from the pure-bending theory results is presented for various core properties. Small deflection dynamic iso-response plots are shown for different core rigidities. To study the limits of small deformation linearity for various sandwich plates, non-linear results for deformations under high pressure loads are compared with the linear results. The …

Excited Atomic Bromine Energy Transfer And Quenching Mechanisms, Ray O. Johnson

Theses and Dissertations

Pulsed and steady-state photolysis experiments have been conducted to determine the rate coefficients for collisional deactivation of the spin-orbit excited state of atomic bromine, Br(²p_1/2). Pulsed lifetime studies for quenching by Br₂ and CO₂, established absolute rate coefficients at room temperature of k_Br2 = 1.2 ± 0.1 x 10^-12 and k_CO2 = 1.5 ± 0.2 x 10^-11 cm³/molecule-s. Steady-state photolysis methods were used to determine the quenching rates for the rare gases, N₂, 0₂, H₂, D₂, NO, …