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Full-Text Articles in Other Operations Research, Systems Engineering and Industrial Engineering

An Analysis Of Early Software Reliability Improvement Techniques, John G. Leonard, Ric K. Nordgren Dec 1997

An Analysis Of Early Software Reliability Improvement Techniques, John G. Leonard, Ric K. Nordgren

Theses and Dissertations

This research explores early life cycle software reliability prediction models or techniques to predict the reliability of software prior to writing code, and a method for increasing or improving the reliability of software products early in the development life cycle. Five prediction models and two development techniques are examined. Each model is statically analyzed in terms of availability of data early in the life cycle, ease of data collection, and whether data is currently collected. One model and the two techniques satisfied those requirements and are further analyzed for their ability to predict or improve software reliability. While the researchers …


Modeling And Comparison Of Wormhole Routed Mesh And Torus Networks, Ronald I. Greenberg, Lee Guan Oct 1997

Modeling And Comparison Of Wormhole Routed Mesh And Torus Networks, Ronald I. Greenberg, Lee Guan

Computer Science: Faculty Publications and Other Works

2D-mesh and torus networks have often been proposed as the interconnection pattern for parallel computers. In addition, wormhole routing has increasingly been advocated as a method of reducing latency. Most analysis of wormhole routed networks, however, has focused on the torus and the broader class of k-ary n-cubes to which it belongs. This paper presents a performance model for the wormhole routed mesh, and it compares the performance of the mesh and torus based on theoretical and empirical analyses.


A Comparison Of The Military's Organic Movement And Commercial Express Carriers, Travis E. Condon, Kirk A. Patterson Sep 1997

A Comparison Of The Military's Organic Movement And Commercial Express Carriers, Travis E. Condon, Kirk A. Patterson

Theses and Dissertations

The DoD has begun outsourcing airlift in order to expedite high priority cargo movement. However, are commercial express carriers more expedient in the cargo delivery than the Air Force organic transportation system? Although anecdotal evidence suggests commercial carriers are faster, little empirical research has been conducted on this subject. This study compares the military's organic transportation system with Federal Express in the delivery of high priority cargo to Spangdahlem Air Base, Germany. The Large Sample Test of Hypothesis was used to determine if there was a significant difference between the cargo transit times of the two. The mean delivery time …


Foreign Military Sales Supply Support: Is There A Better Way?, Eric G. Ellmyer, Won Joon Jang Sep 1997

Foreign Military Sales Supply Support: Is There A Better Way?, Eric G. Ellmyer, Won Joon Jang

Theses and Dissertations

In today's world of declining defense budgets, there is an increasing need for South Korea to ensure they obtain the best dollar value when procuring defense articles. With the increasing financial situation, the purpose of this thesis is to research a surrogate third party firm and determine to what degree South Korea and other foreign military sales customers obtain the best value for their money for follow-on support item procurements. South Korea has participated in the Parts and Repair Ordering System program since its inception. However, South Korea has received little, if any, feedback regarding lead time and cost performance …


Applying Cross-Decking And Activity-Based Costing To Military Distribution Centers: A Proposed Framework, Jonathan P. Elliott, Dwight H. Hintz Jr. Sep 1997

Applying Cross-Decking And Activity-Based Costing To Military Distribution Centers: A Proposed Framework, Jonathan P. Elliott, Dwight H. Hintz Jr.

Theses and Dissertations

Current events and fiscal constraints have focused DoD planners' attention on reducing logistics costs and improving efficiency while maintaining effective combat operations support. Military leaders are seeking private industry best practices that may help the DoD achieve these goals. Two commercially successful business practices that may help the DoD achieve its goals are cross-docking and Activity-Based Costing (ABC). Cross-docking is a commercially proven approach to material distribution through a distribution center that can help reduce inventories, speed material flows, and cut related logistics activity costs. However, the DoD is faced with the challenge of costing current and potential logistics processes …


An Improved Analytical Model For Wormhole Routed Networks With Application To Butterfly Fat-Trees, Ronald I. Greenberg, Lee Guan Aug 1997

An Improved Analytical Model For Wormhole Routed Networks With Application To Butterfly Fat-Trees, Ronald I. Greenberg, Lee Guan

Computer Science: Faculty Publications and Other Works

A performance model for wormhole routed interconnection networks is presented and applied to the butterfly fat-tree network. Experimental results agree very closely over a wide range of load rate. Novel aspects of the model, leading to accurate and simple performance predictions, include (1) use of multiple-server queues, and (2) a general method of correcting queuing results based on Poisson arrivals to apply to wormhole routing. These ideas can also be applied to other networks.


A Value Function Approach To Information Operations Moe's: A Preliminary Study, Michael P. Doyle, Richard F. Deckro, Jack M. Kloeber Jr., Jack A. Jackson Jr., Center For Modeling, Simulation, And Analysis, Air Force Institute Of Technology Jul 1997

A Value Function Approach To Information Operations Moe's: A Preliminary Study, Michael P. Doyle, Richard F. Deckro, Jack M. Kloeber Jr., Jack A. Jackson Jr., Center For Modeling, Simulation, And Analysis, Air Force Institute Of Technology

AFIT Documents

A value focused thinking approach is applied to information operations. A preliminary value hierarchy for information operations is constructed by extracting the values of senior military leadership from existing doctrine. To identify these key values for information operations, applicable existing doctrine was reviewed and summarized. Additionally, hierarchical representations of the values represented within each reviewed doctrine are developed. A value hierarchy requires that supporting objectives be mutually exclusive and collectively exhaustive. Within this analysis, these requirements are enforced, in part, by developed definitions which serve as tests to maintain mutual exclusivity. An exhaustive set of supporting values is also guaranteed …


System Comparison Procedures For Automatic Target Recognition Systems, Anne E. Catlin Mar 1997

System Comparison Procedures For Automatic Target Recognition Systems, Anne E. Catlin

Theses and Dissertations

Estimating the performance of an automatic target recognition (ATR) system in terms of probability of successful target identification involves extensive image collection and processing, which can be very time-consuming and expensive. We investigate the Wald sequential test for the difference in two proportions as a sample size-reducing alternative to ranking and selection and the classical method of comparing binomial confidence intervals. The test is modified for the multiple pairwise comparison of four systems, and is applied to actual data to compare different configurations of the Moving and Stationary Target Acquisition and Recognition (MSTAR) System.


An Object Oriented Simulation Of The C-17 Wingtip Vortices In The Airdrop Environment, Hans J. Petry Mar 1997

An Object Oriented Simulation Of The C-17 Wingtip Vortices In The Airdrop Environment, Hans J. Petry

Theses and Dissertations

This thesis effort focuses on the development of an object-oriented simulation of C-17 personnel airdrop operations and provides a tool for risk assessment of jumper and wingtip vortex interaction. Using the initial modeling efforts of the Wright Laboratory, this model expands those efforts to include random aircraft, wind and jumper movement within the simulation using MODSIM III as its language. Once the model was built, verified, and calibrated, it helped perform a preliminary analysis of jumper risk with varying element spacing and no crosswind. The results of the simulation provided 15 data points with which linear and logistic regression provided …


Optimizing Airborne Area Surveillance Asset Placement, Douglas E. Fuller Feb 1997

Optimizing Airborne Area Surveillance Asset Placement, Douglas E. Fuller

Theses and Dissertations

Currently there is no automated planning tool for the optimum positioning of USAF area surveillance assets for a theater level campaign. This research seeks to find the optimum or near optimum placement of the limited USAF airborne surveillance assets against a theater level target set. The problem of finding the optimum orbit points can be modeled as a classic maximal covering location problem (MCLP). Operational constraints on the placement of surveillance aircraft can be handled by preprocessing the potential orbit points to eliminate infeasible orbit points. Heavy emphasis is placed on preprocessing the data to reduce problem size and hence …


An Integrated Approach To Simulation And Activity-Based Costing For Evaluating Alternative Manufacturing Cell Designs, Robert Williams, Paul Savory, Rodney Rasmussen Jan 1997

An Integrated Approach To Simulation And Activity-Based Costing For Evaluating Alternative Manufacturing Cell Designs, Robert Williams, Paul Savory, Rodney Rasmussen

Department of Industrial and Management Systems Engineering: Faculty Publications

One effective technique for improving manufacturing efficiency involves the application of group technology part families and manufacturing cells. Selection of the best or optimum configuration of the manufacturing cell relies on the experience and judgment of the cell designer. This paper describes how activity-based costing (ABC) concepts can be integrated into a discrete-event simulation model and be used to evaluate manufacturing cell configurations. The output of the combined ABC simulation model provides a detailed “Bill of Activity” which allows the cell designer to consider costs as a critical factor in the cell design problem. Alternative cell configurations studied in this …


Simulating Queue Scheduling Policies For A Spacecraft Simulator, Paul Savory, Gene Saghi Jan 1997

Simulating Queue Scheduling Policies For A Spacecraft Simulator, Paul Savory, Gene Saghi

Department of Industrial and Management Systems Engineering: Faculty Publications

The mission of the Cassini spacecraft is a unique opportunity to gain insights into major scientific questions about Saturn, the creation of the solar system, and the conditions that led to life on Earth. In preparation for the launch, NASA's Jet Propulsion Laboratory developed a software simulator to emulate the hardware data-control system of the spacecraft. Its primary use is to validate and verify commands that will be transmitted to the spacecraft. To improve the performance of the simulator, we used the SIMAN simulation language to model numerous queue-scheduling policies. Implementation of the simulation results combined with a software-code redesign …


Selecting For Random Drug Testing At Union Pacific Railroad, Jennifer Meyer, Paul Savory Jan 1997

Selecting For Random Drug Testing At Union Pacific Railroad, Jennifer Meyer, Paul Savory

Department of Industrial and Management Systems Engineering: Faculty Publications

Many industries have recently implemented programs to detect and deter the use of recreational drugs in the workplace. The transportation industry has received careful government attention, particularly where the safety of the public may be seriously affected by employees who use drugs. Following federal guidelines, Union Pacific Railroad first implemented a random drug-testing plan in 1990. Because the assigned jobs, shifts, and work locations of many railroad employees change frequently, defining the selection population was particularly challenging. In its continuing efforts to validate and improve this plan, Union Pacific Railroad sought an external evaluation to determine the fairness of its …


An Aggregation Procedure For Simulating Manufacturing Flow Line Models, Paul Savory, Gerald Mackulak Jan 1997

An Aggregation Procedure For Simulating Manufacturing Flow Line Models, Paul Savory, Gerald Mackulak

Department of Industrial and Management Systems Engineering: Faculty Publications

We develop a formal method for specifying an aggregate discrete-event simulation model of a production flow line manufacturing system. The methodology operates by aggregating production stations or resources of a flow line. Determining the specifications for representing the aggregated resources in a simulation model is the focus of our presentation. We test the methodology for a set of flow lines with exponentially distributed arrival and service times. Comparisons between analytical and simulation results indicate the aggregation approach is quite accurate for estimating average part cycle time.