Engineering Commons^™

Application Of Executable Architectures In Early Concept Evaluation, Ryan M. Pospisal

Theses and Dissertations

This research explores use of executable architectures to guide design decisions in the early stages of system development. Decisions made early in the system development cycle determine a majority of the total lifecycle costs as well as establish a baseline for long term system performance and thus it is vital to program success to choose favorable design alternatives. The development of a representative architecture followed the Architecture Based Evaluation Process as it provides a logical and systematic order of events to produce an architecture sufficient to document and model operational performance. In order to demonstrate the value in the application …

Collecting Unsolicited User-Generated Change Requests, Joseph W. Goldsmith

Theses and Dissertations

Unlike aircrew directly associated with acquisitions, line operators are not fully engaged in the methods to push materiel hardware or software change requests up the chain, to a decision maker, and then to the engineers. The Air Force trains these end users to logically apply expert systems knowledge to execute the mission but has not fully leveraged this resource for properly identifying and correcting operational shortfalls in an aircraft's design. Focusing on the Remotely Piloted Aircraft (RPA) community, the research goal is to determine if the Air Force should establish a formal program for collecting and prioritizing unsolicited user change …

Continuous Decision Support, Jeremy P. Hendrix

Theses and Dissertations

Organizations are often faced with portfolio construction efforts that require them to select one or more alternatives, subject to resource constraints, with the aim of achieving the maximum value possible. This is a well-defined problem with a number of analytically defensible approaches, provided the entire set of alternatives is known when the decision event takes place. Less well treated in the literature is how to approach this problem when the entire set of alternatives is unknown, as when the alternatives arrive over time. This change in the availability of data shifts the problem from one of identifying an optimal subset …

An Economical Model Development For A Hybrid System Of Grid Connected Solar Pv And Electrical Storage System, Mohammad Hasan Balali

Theses and Dissertations

Energy sources management is one of the most important concern in the recent decades. There are finite amount of non-renewable energy sources and one day they will run out if they have been used as primary sources of energy. Renewable energy sources have been significantly reduced the environmental effects. For most of them the source of energy is non-depletable.

One of the concerns associated with renewable resources is uncertainty or unavailability. Energy Storage Systems (ESSs) can help to have more reliable and more efficient systems by adjusting the charge and discharge time and rate. In this study, an economic model …

Warranty Period And Product Price Optimization For Remanufactured Products, Yuxi Liu

Theses and Dissertations

This study considers a remanufactured electrical product under a tiered warranty policy. Warranty is key in ensuring a good manufacturer—consumer relationship. Manufacturers hope to minimize warranty costs while consumers believe that good warranty promises better product quality and reliability. This Thesis presents an optimal warranty period from the perspective of a manufacturer to maximize the total expected profits, while ensuring sustained consumer relation. We use real data from a local company with a global supply chain to provide a numerical example.

Biomechanical Evaluation Of Three Post-Kneeling Tasks: Sitting, Walking, And Standing, Alexa Hernandez Principe

Theses and Dissertations

There are several occupations that require prolonged kneeling as part of their daily practice. Employees who kneel for a prolonged period of time have been reported to have high rates of knee and low back musculoskeletal disorders (Coggon et al. 2000, Halmstrom et al. 1992, Harkness et al. 2003, Manninen et al. 2002). These disorders result in excessive worker’s compensation costs. Gallagher el al. (2009) looked at the low seam mining industry and found that companies spent the most on knee related injuries with $4.2 million and $2.7 million for low back injuries.

There is a lack of knowledge available …

A Systems Approach To Point Source Indication Of Metformin Found In Local Water Systems – The Case Of Milwaukee County, Mohamed Salem Baitelmal

Theses and Dissertations

Pharmaceutical pollutants are present in traceable concentrations in Milwaukee County water system and Lake Michigan. The actual point sources and nature of entry into the water system is difficult to determine with certainty. Pharmaceuticals have been found to persist at the South Shore Wastewater Treatment Facility (SSWTF) in Milwaukee, Wisconsin. The highest concentration was found to be for the pharmaceutical drug metformin. Metformin is a first line drug for the treatment of type 2 diabetes mellitus.

The broad goal of this exploratory study; the first of its kind, is to correlate trace concentrations of drugs to the point sources. Particularly, …

Water Withdrawal And Consumption Reduction Analysis For Electrical Energy Generation System, Narjes Nouri

Theses and Dissertations

There is an increasing concern over shrinking water resources. Water use in the energy sector primarily occurs in electricity generation. Anticipating scarcer supplies, the value of water is undoubtedly on the rise and design, implementation, and utilization of water saving mechanisms in energy generation systems are becoming inevitable. Most power plants generate power by boiling water to produce steam to spin electricity-generating turbines. Large quantities of water are often used to cool the steam in these plants. As a consequence, most fossil-based power plants in addition to consuming water, impact the water resources by raising the temperature of water withdrawn …

Characterizing The Effects Of Capillary Flow During Liquid Composite Molding, Michael Ray Morgan

Theses and Dissertations

As the aerospace industry continues to incorporate composites into its aircraft, there will be a need for alternative solutions to the current autoclaving process. Liquid composite molding (LCM) has proven to be a promising alternative, producing parts at faster rates and reduced costs while retaining aerospace grade quality. The most important factor of LCM is controlling the resin flow throughout the fiber reinforcement during infusion, as incomplete filling of fibers is a major quality issue as it results in dry spots or voids. Void formation occurs at the resin flow front due to competition between viscous forces and capillary pressure. …

Integrating Process Mining With Discrete-Event Simulation Modeling, Siyao Liu

Theses and Dissertations

Discrete-event simulation (DES) is an invaluable tool which organizations can use to help better understand, diagnose, and optimize their operational processes. Studies have shown that for the typical DES exercise, the greatest amount of time is spent on developing an accurate model of the process that is to be studied. Process mining, a similar field of study, focuses on using historical data stored in software databases to accurate recreate and analyze business processes. Utilizing process mining techniques to help rapidly develop DES models can drastically reduce the amount of time spent building simulation models, which ultimately will enable organizations to …

Deriving System Vulnerabilities Using Log Analytics, Matthew Somers Higbee

Theses and Dissertations

System Administrators use many of the same tactics that are implemented by hackers to validate the security of their systems, such as port scanning and vulnerability scanning. Port scanning is slow, and can be highly inaccurate. After a scan is complete, the results of the scan must be cross checked with a vulnerability database to discover if any vulnerabilities are present. While these techniques are useful, they have severe limitations. System Administrators have full access to all of their machines. They should not have to rely exclusively on port scanning them from the outside of their machines to check for …

Integrated Systems Health Management As An Enabler For Condition Based Maintenance And Autonomic Logistics, Robert M. Vandawalker

Theses and Dissertations

Health monitoring systems have demonstrated the ability to detect potential failures in components and predict how long until a critical failure is likely to occur. Implementing these systems on fielded structures, aircraft, or other vehicles is often a struggle to prove cost savings or operational improvements beyond improved safety. A system architecture to identify how the health monitoring systems are integrated into fielded aircraft is developed to assess cost, operations, maintenance, and logistics trade-spaces. The efficiency of a health monitoring system is examined for impacts to the operation of a squadron of cargo aircraft revealing sensitivity to and tolerance for …

Grabbing The Air Force By The Tail: Applying Strategic Cost Analytics To Understand And Manage Indirect Cost Behavior, Bradley C. Boehmke

Theses and Dissertations

Recent and projected reductions in defense spending are forcing the military services to develop systematic approaches to identify cost reduction opportunities and better manage financial resources. In response, the Air Force along with her sister services are developing strategic approaches to reduce front-line mission resources, commonly referred to as the Tooth . However, an underemphasized contributing source of costs are mission support activities, commonly referred to as the Tail . With the tail historically representing a sizable portion of the annual Air Force budget, strategically managing cost behavior of these indirect activities has the opportunity to generate significant cost reductions. …

Classification Of Adequate Impact Protection For Hands, Patrick Dylan Loshek

Theses and Dissertations

ABSTRACT

CLASSIFICATION OF ADEQUATE

IMPACT PROTECTION FOR HANDS

by

Patrick D. Loshek

The University of Wisconsin-Milwaukee, 2015

Under the Supervision of Professor Naira Campbell-Kyureghyan

Historically, hand injuries have been a large burden for the manufacturing, construction, mining, oil and gas industries. Specially designed gloves are commonly used in industry today to protect hands from impacts. These gloves are designed to reduce hand injuries by absorbing the impact forces workers may encounter due to objects striking the hand. However, to date, there is no standard for the testing of these gloves and quantifying the force reduction a user would experience when …

Transient Performance Analysis Of Serial Production Lines, Yang Sun

Theses and Dissertations

TRANSIENT PERFORMANCE ANALYSIS OF

SERIAL PRODUCTION LINES

by

Yang Sun

The University of Wisconsin-Milwaukee, 2015

Under the Supervision of Professor Liang Zhang

Production lines with unreliable machines and finite buffers are characterized by both steady-state performance and transient behavior. The steady-state performance has been analyzed extensively for over 50 years. Transient behavior, however, is rarely studied and remains less explored. In practice, a lot of the real production systems are running partially or entirely in transient periods. Therefore, transient analysis is of significant practical importance.

Most of the past research on production systems focuses on discrete materials flow which utilities …

Optimal Cyclic Control Of A Buffer Between Two Consecutive Non-Synchronized Manufacturing Processes, Wenhuan Hsieh

Theses and Dissertations

This thesis presents methods for efficiently controlling a buffer that is located between two non-synchronized manufacturing processes. Several machines with different cycle times and/or batch sizes perform each manufacturing process. The overall operation cycles every T time units. The first objective of the problem is to minimize the average buffer inventory level during one cycle. The second objective is to minimize the maximum inventory level observed at any point during the cycle. This new optimization problem has not been previously considered in the literature. An integer program is developed to model this problem. In addition, two heuristic methods—a simulated annealing …

Usage Analysis Of Milwaukee County's Paratransit System: The Case Of Potawatomi Casino And Veteran Affairs Medical Center Destinations, Po-Hsueh Chiu

Theses and Dissertations

In order to protect the rights of seniors and Persons with Disabilities (PWDs), the United States government, through Congress, enacted the Americans with Disabilities Act (ADA) in 1990. The Act ensures that there is equity for persons with disabilities in all aspects of public services including employment, education, transportation, accommodation, commercial facilities and businesses and communication (Federal Register, 2010). In this study, we focus on the problem of transportation of PWDs, specifically in Milwaukee County in Southeast Wisconsin. The study was initiated as a collaborative effort between UWM’s Industrial and Manufacturing Engineering team, UWM’s Director of the Rehabilitation Research Design …

Individual, Occupational And Biomechanical Factors That Affect Slip And Fall Risk From Fixed Ladders, Erika Mae Pliner

Theses and Dissertations

Injuries from ladder falls are prevalent and severe. Previous research has examined certain elements of ladder falls such as the ladder base slipping, but few studies have examined the factors that contribute to climbers falling from the ladder, particularly for permanent/fixed ladders. In addition, the biomechanical response to a ladder slip/misstep during ladder climbing and the factors that affect a fall from a ladder are not well understood. This thesis is a two part study that simulated ladder slips and missteps in order to find factors 1) associated with ladder slip risk and 2) that decrease fall severity from a …

A Simple Method For Evaluating Wear In Different Grades Of Tooling Applied To Friction Stir Spot Welding, Kirtis Frankland Kennard

Theses and Dissertations

In this study tools consisting of a 5mm cylindrical pin and a 12mm shoulder held by a simple tool holder were used to compare the wear of 11 tooling materials. The objective was to determine if using these tools in a spot welding configuration to simulate friction stir welding could differentiate the potential performance of tooling materials. All tools were made of varying percentages of polycrystalline cubic boron nitride (PCBN), tungsten (W) and rhenium (Re). The materials are referred to herein as GV1, GV2, G1, G2, G3, G4, G5, G6, G7, G8 and G9.

The tools were run to 205 …

Terminological Mediation In Information Technology And Related Fields, Jessica Smith Richards

Theses and Dissertations

Terminological dissonance is created by the inherent ambiguity of natural language and compounded by ontological specialization efforts within fields. Terminological dissonance creates high-risk miscommunications in two key areas: within Information Technology as a singular domain, and also between IT and other fields in interdisciplinary projects. A comprehensive literature review revealed a lack of previous effort to acknowledge or solve problems of terminological dissonance within Information Technology. This research provides a comprehensive overview and definition of the terminology mediation space as it relates to Information Technology and adjacent fields. An analysis and verification of the contents and implementation of the terminology …

Supply Chain Interoperability Measurement, Christos E. Chalyvidis

Theses and Dissertations

Academia recognizes that although supply chains have an inherent need to be validated for their performance, supply chain performance measurement systems are still inadequate and one of the major barriers to successful supply chain collaboration. In this research, theory of Systems Architecture is used to make the first step towards an innovative supply chain performance measure defined as supply chain interoperability. Interoperability is considered a similarity metric with regard to a set of deterministic and stochastic characters (criteria) describing supply chain participants, a methodology that adapts and expands an interoperability measurement tool initially developed in and for a military context. …

A Method To Predict Compressor Stall In The Tf34-100 Turbofan Engine Utilizing Real-Time Performance Data, Shuxiang A. Li, Trevor G. Jones

Theses and Dissertations

The Air Force current operations continue to undergo significant changes compelled by decreasing fiscal appropriations, aging aircraft, and personnel drawdown. The Air Force must effectively improve current maintenance operations in part to deal with these challenges. This study will explore the area of the A-10 aircraft fleet's TF34-100 high-pass turbo-fan engine sensor data to seek its deterioration modelling and prognostics capability. In futurity this will allow for achievement of greater confidence in predicting the compressor stall which leads to engine performance deterioration and a costly repair in maintenance. By utilizing an innovative method to forecast the probability of compressor stall, …

An Assessment Of The Effectiveness Of Air Force Risk Management Practices In Program Acquisition Using Survey Instrument Analysis, Michael J. Maroney Jr.

Theses and Dissertations

Air Force acquisition programs invest a large amount of resources to develop and field systems. Many of these resources go to risk management in order to help ensure those programs finish successfully with respect to cost, schedule, and technical performance goals. The question arises as to whether this is a sound investment. Although risk management has been shown to be effective in industry, scant empirical evidence exists for its effectiveness within the Air Force. Correlation and regression analysis of survey data show that a positive relationship does exist between specific risk practices and project success. Furthermore, the analysis suggests that …

Analysis Of The Effectiveness Of The F-15e Risk Management During Peacetime Operations, Elliot B. Vasquez

Theses and Dissertations

Human factors are causal or contributory in 80% of Class A mishaps in the Air Force. Risk management tools are used throughout the service in every aircraft to help mitigate the risk of those human factors occurring. The F-15E Strike Eagle community was selected for analysis on the effectiveness of its risk management program but the data was comprised on Class A mishaps from Accident Investigation Boards since 2000 between the F-15 (all models), F-16 (all models), and F-22. Cases were selected if there were human factors root causes or contributory. A fault tree analysis coupled with the Department of …

Minimizing Average Handling Time In Contact Centers By Introducing A New Process: Rowan Support Desk Case Study, Niusha Jafari

Theses and Dissertations

Quality of a call center performance is an important factor in insuring customer satisfaction. Customers, the "callers", want their requests solved quickly, permanently and to their satisfaction. Often, there are staff constraints, budget or cost limitation, and the Service Level Agreement (SLA) which is resource availability to accomplish a task within a deadline. The purpose of this research is to analyze feasible approaches to minimize the long-lasting open requests and enhance a call center's performance. Multiple challenges that a call center often faces in handling requests are studied to identify key bottlenecks in the process of handling requests. Rowan University …

Void Modeling In Resin Infusion, Mark Wesley Brandley

Theses and Dissertations

Resin infusion of composite parts has continually been reaching to achieve laminate quality equal to, or exceeding, the quality produced with prepreg in an autoclave. In order for this to occur, developers must understand the key process variables that go in to producing a laminate with minimal void content. The purpose of this research is to continue efforts in understanding 1) the effect of process conditions on the resultant void content, with a focus on resin infusion flow rate, 2) applying statistical metrics to the formation, location and size of voids formed, and 3) correlate these metrics with the local …

Service Dependency Analysis Via Tcp/Udp Port Tracing, John K. Clawson

Theses and Dissertations

Enterprise networks are traditionally mapped via layers two or three, providing a view of what devices are connected to different parts of the network infrastructure. A method was developed to map connections at layer four, providing a view of interconnected systems and services instead of network infrastructure. This data was graphed and displayed in a web application. The information proved beneficial in identifying connections between systems or imbalanced clusters when troubleshooting problems with enterprise applications.

Friction Bit Joining Of Dissimilar Combinations Of Dp 980 Steel And Aa 7075, Rebecca Hilary Peterson

Theses and Dissertations

Friction Bit Joining (FBJ) is a new technology that allows lightweight metals to be joined to advanced high-strength steels (AHSS). Joining of dissimilar metals is especially beneficial to the automotive industry because of the desire to use materials such as aluminum and AHSS in order to reduce weight and increase fuel efficiency. In this study, FBJ was used to join 7075 aluminum and DP980 ultra-high-strength steel. FBJ is a two-stage process using a consumable bit. In the first stage, the bit cuts through the top material (aluminum), and in the second stage the bit is friction welded to the base …

A Predictive Logistic Regression Model Of World Conflict Using Open Source Data, Benjamin C. Boekestein

Theses and Dissertations

Nations transitioning into conflict is an issue of national interest. This study considers various data for inclusion in a statistical model that predicts the future state of the world where nations will either be in a state of violent conflict or not in violent conflict based on available historical data. Logistic regression is used to construct and test various models to produce a parsimonious world model with 15 variables. Further analysis shows that nations differ significantly by geographical area. Therefore six sub-models are constructed for differing geographical areas of the world. The dominant variables for each sub-model vary, suggesting a …

Overcoming Hurdles Implementing Multi-Skilling Policies, Joshua M. Isom

Theses and Dissertations

Ogden ALC at Hill AFB has been authorized to promote wage grade employees if they are multi-skilled, but that authorization will expire at the end of Fiscal Year 2018. Simulation research by Capt Wesley Sheppard demonstrated significant cost savings/cost avoidance if multi-skilling is pursued, but there are significant challenges to implementation. This research examined two challenges in implementation. First, how many employees can be multi-skilled and still maintain proficiency in both skills? Second, once multi-skilled, is there a technique that can be applied to easily and effectively schedule the new multi-skilled workforce. Using linear programming, staffing numbers were calculated based …