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2011

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

Simulation-Based Optimisation Model For The Lean Assessment In Sme: A Case Study, Amr Arisha, Amr Mahfouz, John Shea Dec 2011

Simulation-Based Optimisation Model For The Lean Assessment In Sme: A Case Study, Amr Arisha, Amr Mahfouz, John Shea

Conference papers

Due to their space limitation and small production scale, small and medium enterprises (SME) are vulner-able to rapid changes. Lean principles are considered as effective improvement approach to eliminate sys-tem’s waste and inefficiencies. Although much of the academic materials have addressed the lean practic-es into large, global companies, they can still be adjusted to SMEs. Risks are usually associated with lean implementation process due to the drastic required changes in business policies and operations. Simulation can be successfully used to predict the impact of the proposed changes ahead of the implementation which helps to mitigate risks. Integrating simulation with optimization …


Inventory Models For Intermittent Highly Variable Demand And Policy Parameter Adjustments To Meet Desired Service Level Requirements, Yasin Unlu Dec 2011

Inventory Models For Intermittent Highly Variable Demand And Policy Parameter Adjustments To Meet Desired Service Level Requirements, Yasin Unlu

Graduate Theses and Dissertations

This dissertation consists of three assays. The first assay examines the robustness of lead time demand models for the continuous review (r;Q) inventory policy. A number of classic distributions as well as distribution selection rules are examined under a wide variety of demand conditions. First, the models are compared to each other by assuming a known demand process and evaluating the errors associated with using a different model. Then, the models are examined using a large sample of simulated demand conditions. Approximation results of inventory performance measures - ready, rate excepted number of backorders and on-hand inventory levels are reported. …


Improvements On Just-About-Right (Jar) Scales As Product Optimization Tools Using Kano Modeling Concepts, Bangde Li Dec 2011

Improvements On Just-About-Right (Jar) Scales As Product Optimization Tools Using Kano Modeling Concepts, Bangde Li

Graduate Theses and Dissertations

Attribute Kano characteristics are useful in product design to prioritize development efforts. However, attribute Kano characteristics have not been discussed and applied to product optimization when using Just-About-Right (JAR) scales. Product optimizations without identifying attributes Kano characteristics can be misleading. The two objectives in this research were: 1. Determine attribute Kano categories using a modified classic Kano classification methodology. 2. Propose a method to measure attribute performance and identify attribute Kano characteristics to direct product optimization. Two methodologies of attribute Kano classification were investigated. In experiment one, a modified classic Kano methodology was employed to determine attribute Kano categories through …


Ethnic Difference In Healthcare Delivery, Benny Mathew Varghese Dec 2011

Ethnic Difference In Healthcare Delivery, Benny Mathew Varghese

Department of Industrial and Management Systems Engineering: Dissertations, Theses, and Student Research

Quality in healthcare is a very important aspect; this is obtained when there is proper care provided to the patients without any discrimination. The healthcare system in the US can be improved in the fields of patient’s care, the amount of money spent and proper advice, if proper responsibilities are taken. Quality has been improving over the years, but the median by which there is an increase is too small. The other main factor is access to the healthcare system, which has over the year, has not progressed. Studies in healthcare quality should be conducted on a regular base, so …


Adaptive Intensity Modulated Radiation Therapy Planning Optimization With Changing Tumor Geometry And Biology Enforcing Both Cumulative And Fraction Size Dose Constraints, Behlul Saka Dec 2011

Adaptive Intensity Modulated Radiation Therapy Planning Optimization With Changing Tumor Geometry And Biology Enforcing Both Cumulative And Fraction Size Dose Constraints, Behlul Saka

Graduate Theses and Dissertations

Intensity Modulated Radiation Therapy (IMRT) is a modern technique of delivering radiation treatments to cancer patients. In IMRT technology, intensities must be chosen for the many small unit grids into which the beams are divided to produce a desired distribution of dose at points throughout the body with the goal of maximizing dose delivered to the tumor while sparing healthy tissues from excessive radiation and keeping dose homogeneous across the tumor. Although IMRT plans are optimized as a single overall treatment plan, they are delivered over 30-50 treatment sessions (fractions) and both cumulative and per-fraction dose constraints apply. The extended …


Modeling And Analysis Of High Energy Laser Weapon System Performance In Varying Atmospheric Conditions, Megan P. Melin Sep 2011

Modeling And Analysis Of High Energy Laser Weapon System Performance In Varying Atmospheric Conditions, Megan P. Melin

Theses and Dissertations

This thesis addresses two primary concerns relating to Directed Energy (DE) models and tests: need for more use of Design of Experiment (DOE) in structuring DE models and tests, and lack of modeling atmospheric variability in High Energy Laser (HEL) weapon system propagation models and tests. To address these concerns we use a DOE factorial design to capture main, interaction, and non-linear effects between modeled weapon design and environmental factors in a well defined simulated Air-to-Ground HEL engagement scenario. The scenario modeled considers a B1-B aircraft in the 2022 timeframe equipped with an HEL weapon, irradiating a ground target from …


Identification And Classification Of Player Types In Massive Multiplayer Online Games Using Avatar Behavior, Earl M. Bednar Sep 2011

Identification And Classification Of Player Types In Massive Multiplayer Online Games Using Avatar Behavior, Earl M. Bednar

Theses and Dissertations

The purpose of our research is to develop an improved methodology for classifying players (identifying deviant players such as terrorists) through multivariate analysis of data from avatar characteristics and behaviors in massive multiplayer online games (MMOGs). To build our classification models, we developed three significant enhancements to the standard Generalized Regression Neural Networks (GRNN) modeling method. The first enhancement is a feature selection technique based on GRNNs, allowing us to tailor our feature set to be best modeled by GRNNs. The second enhancement is a hybrid GRNN which allows each feature to be modeled by a GRNN tailored to its …


Evaluation Of A Shared Representation To Support Collaborative, Distributed, Coalition, Multilevel Planning, Michael C. Dorneich, David Mott, Ali Bahrami, Jitu Patel, Cheryl Giammanco Sep 2011

Evaluation Of A Shared Representation To Support Collaborative, Distributed, Coalition, Multilevel Planning, Michael C. Dorneich, David Mott, Ali Bahrami, Jitu Patel, Cheryl Giammanco

Michael C. Dorneich

This paper presents the extension and evaluation of a formal representation that enables planners at different levels of command, and in different functional area, to jointly share, develop, and modify plans. Planning has moved from a co-located, concurrent, small team activity to an activity that involves a large, culturally diverse, hierarchical, globally-distributed team. However, significant benefits of distributed planning can only come if the team is able to communicate and maintain a shared understanding of the commander’s intent, objectives, resources and constraints, as well as decisions made and justifications for planning options chosen or alternatives rejected. Effective automated support must …


Characterization Of Key Process Parameters In Injection Blow Molding For Improving Quality, Aspen D'Costa Aug 2011

Characterization Of Key Process Parameters In Injection Blow Molding For Improving Quality, Aspen D'Costa

Online Journal for Workforce Education and Development

The purpose of this study was to discover the performance of significant process parameters in manufacturing 20 oz. plastic beverage bottles. An experimental methodology was carefully designed to examine the characteristics of key variables such as ambient and operating temperatures, process line operators, resin types, resin colors and operating lines associated with a plastic bottle manufacturing line. More explicitly, this study seeks to identify the definitive relationship between the selected process parameters for the production machine (Sidel™) and the ensuing product quality. Also, this study was conducted to evaluate the performance characteristics of Post Consumer Resin (PCR), virgin resin and …


Assessment System Based On Fuzzy Scoring In European Foundation For Quality Management (Efqm) Business Excellence Model, J Dodangeh Aug 2011

Assessment System Based On Fuzzy Scoring In European Foundation For Quality Management (Efqm) Business Excellence Model, J Dodangeh

Javad Dodangeh

There are a few popular business excellence models that provide standard criteria against which an organization can measure its performances. European Foundation for Quality Management (EFQM) is the most popular one. The organizational self-assessment process is an admissible system in the area of Total Quality Management (TQM). Most specialists concur to the description of self-assessment that is presented by the European Foundation for Quality Management (EFQM). However, the current selfassessment methods in EFQM model have some drawbacks and problems which are scoring in these methods influenced by experts’ judgment and thus, are subjective. Furthermore, these methods cannot consider the empirical …


Optimization Of Supply Chain Planning With Considering Defective Rates Of Products In Each Echelon, Behin Elahi Jul 2011

Optimization Of Supply Chain Planning With Considering Defective Rates Of Products In Each Echelon, Behin Elahi

Behin Elahi

Supply Chain Planning has recently received considerable attention in both academia and industry. The major targets of supply chain planning are to reduce production costs, risks, delays and maximize or improve profit, quality of product, customer service which result in increased competitiveness, more customer satisfaction and portability. In this study, a new bi-objective mathematical modeling for a four-echelon supply chain, consisting multi-supplier, assembler, distribution center and retailer, with considering the defective rates of products is proposed. Then, fuzzy compromise programming method is applied to solve the non-linear mixed-integer bi-objective model. Finally, a numerical example is given to illustrate application of …


Designing Fuzzy Multi Criteria Decision Making Model For Best Selection Of Areas For Improvement In Efqm, J Dodangeh Jun 2011

Designing Fuzzy Multi Criteria Decision Making Model For Best Selection Of Areas For Improvement In Efqm, J Dodangeh

Javad Dodangeh

In a growingly competitive business environment, numerous organizations adopt the total quality management (TQM) approach, to struggle for business excellence. To monitor the progress towards business excellence, thousands of organizations across the world use self-assessment on a regular basis. There are a few popular business excellence models, that provide standard criteria against which an organization can measure its performances. European Foundation for Quality Management (EFQM) is the most popular ones. The EFQM Excellence Model was introduced at the beginning of 1992, as the framework for assessing organizations for the European Quality Award. It is now the most widely used organizational …


Face Recognition Via Ensemble Sift Matching Of Uncorrelated Hyperspectral Bands And Spectral Pcts, Mohd Fairul Mohd-Zaid Jun 2011

Face Recognition Via Ensemble Sift Matching Of Uncorrelated Hyperspectral Bands And Spectral Pcts, Mohd Fairul Mohd-Zaid

Theses and Dissertations

Face recognition is not a new area of study, but facial recognition using through hyperspectral images is a somewhat new concept which is still in its infancy. Although the conventional method of face recognition using Red-Green-Blue (RGB) or grayscale images has been advanced over the last twenty years, these methods are still shown to have weak performance whenever there are variations or changes in lighting, pose, or temporal aspect of the subjects. A hyperspectral representation of an image captures more information that is available within a scene than a RGB image therefore it is beneficial to study the performance of …


An Optimization Approach To Employee Scheduling Using Fuzzy Logic, William G. Spence Jun 2011

An Optimization Approach To Employee Scheduling Using Fuzzy Logic, William G. Spence

Master's Theses

An Optimization Approach to Employee Scheduling Using Fuzzy Logic

William G. Spence

Selection of sales employees is critical because the sales employees represent the company’s image, competitive advantage, technology, and values. In many service systems the majority of consumer contact is with the sales department. Since there are different types of customers, scheduling quality salespersons who can adequately help consumers may affect revenue.

This thesis proposes a new methodology for the scheduling of employees in a service system. The methodology uses Fuzzy Logic to calculate possible sales and Linear Programming to create an optimal schedule. This approach enables the rating …


A Multi-Commodity Network Flow Approach For Sequencing Refined Products In Pipeline Systems, Rolando José Acosta Amado May 2011

A Multi-Commodity Network Flow Approach For Sequencing Refined Products In Pipeline Systems, Rolando José Acosta Amado

Doctoral Dissertations

In the oil industry, there is a special class of pipelines used for the transportation of refined products. The problem of sequencing the inputs to be pumped through this type of pipeline seeks to generate the optimal sequence of batches of products and their destination as well as the amount of product to be pumped such that the total operational cost of the system, or another operational objective, is optimized while satisfying the product demands according to the requirements set by the customers. This dissertation introduces a new modeling approach and proposes a solution methodology for this problem capable of …


Interaction Between Primary Resources And Root Causes In Lean Production Systems, Ernest Anene Iwuchukwu May 2011

Interaction Between Primary Resources And Root Causes In Lean Production Systems, Ernest Anene Iwuchukwu

Masters Theses

A model to analyze lean systems reliability is developed based on the premises that lean production systems require four primary resources; materials, equipment, personnel, and schedule (Sawhney, R., Subburaman, K., Sonntag, C., Capizzi, C. and Rao, P.V., 2009). The four primary lean resources were independently analyzed, without due consideration to underlying relationships within each other. In this research, relationships and interaction between root-causes and lean primary resources were conceptualized and developed. The development applied a five-phase approach: 1. review of related literature, 2. decompositions of lean primary resources, 3. selection of consensus root causes items and questionnaire construct, 4. survey …


Analyzing Supercomputer Utilization Under Queuing With A Priority Formula And A Strict Backfill Policy, Michael David Vanderlan May 2011

Analyzing Supercomputer Utilization Under Queuing With A Priority Formula And A Strict Backfill Policy, Michael David Vanderlan

Masters Theses

Supercomputers have become increasingly important in recent years due to the growing amount of data available and the increasing demand for quicker results in the scientific community. Since supercomputers carry a high cost to build and maintain, efficiency becomes more important to the owners, administrators, and users of these supercomputers. One important factor in determining the efficiency of a supercomputer is the scheduling of jobs that are submitted by users of the system. Previous work has dealt with optimizing the schedule on the system’s end while the users are blinded from the process. The work presented in this thesis investigates …


Examination Timetabling With Mathematical Programming An Application In Turkish Air Force Academy, Emrah Koksalmis Apr 2011

Examination Timetabling With Mathematical Programming An Application In Turkish Air Force Academy, Emrah Koksalmis

Engineering Management & Systems Engineering Theses & Dissertations

The focus of this thesis is the educational timetabling problem, which is a very challenging problem to solve especially with a high number of the departments, branches, classes, and students. Due to the large scale of educational timetabling problems and preferences of the stakeholders, it is almost impossible to form a general model that solves all of the timetabling problems in the literature. This resulted in the need to develop and employ specific models for specific institutions.

The purpose of this study is to develop a mathematical programming model that solves the examination timetabling problem in Turkish Air Force Academy …


Optimization Models And Approximate Algorithms For The Aerial Refueling Scheduling And Rescheduling Problems, Sezgin Kaplan Apr 2011

Optimization Models And Approximate Algorithms For The Aerial Refueling Scheduling And Rescheduling Problems, Sezgin Kaplan

Engineering Management & Systems Engineering Theses & Dissertations

The Aerial Refueling Scheduling Problem (ARSP) can be defined as determining the refueling completion times for fighter aircrafts (jobs) on multiple tankers (machines) to minimize the total weighted tardiness. ARSP can be modeled as a parallel machine scheduling with release times and due date-to-deadline window. ARSP assumes that the jobs have different release times, due dates, and due date-to-deadline windows between the refueling due date and a deadline to return without refueling. The Aerial Refueling Rescheduling Problem (ARRP), on the other hand, can be defined as updating the existing AR schedule after being disrupted by job related events including the …


A Method To Improve The Sustainment Of Systems Based On Probability And Consequences, Michael Ashton Gaintner Apr 2011

A Method To Improve The Sustainment Of Systems Based On Probability And Consequences, Michael Ashton Gaintner

Engineering Management & Systems Engineering Theses & Dissertations

The FROST Method is presented which improves the efficiency of long-term sustainment of hardware systems. The FROST Method makes sustainment and scheduling decisions based on the minimization of the expected value of current and future costs. This differs from current methods which tend to base decisions not on the expected value of costs, but on the expected inventory demand found through projections using data which is often inaccurate.

Distributions are used to account for randomness and inaccuracy in inputs such as failure rates and vendor-claimed dates for end of production. A Monte Carlo technique is then used to convert these …


A Hybrid Lehmer Code Genetic Algorithm And Its Application On Traveling Salesman Problems, Jun Zhang Apr 2011

A Hybrid Lehmer Code Genetic Algorithm And Its Application On Traveling Salesman Problems, Jun Zhang

Engineering Management & Systems Engineering Theses & Dissertations

Traveling Salesman Problems (TSP) is a widely studied combinatorial optimization problem. The goal of the TSP is to find a tour which begins in a specific city, visits each of the remaining cities once and returns to the initial cities such that the objective functions are optimized, typically involving minimizing functions like total distance traveled, total time used or total cost.

Genetic algorithms were first proposed by John Holland (1975). It uses an iterative procedure to find the optimal solutions to optimization problems.

This research proposed a hybrid Lehmer code Genetic Algorithm. To compensate for the weaknesses of traditional genetic …


Improving Compressed Air Energy Efficiency In Automotive Plants: Practical Examples And Implementation, Nasr Alkadi, J. Kelly Kissock Apr 2011

Improving Compressed Air Energy Efficiency In Automotive Plants: Practical Examples And Implementation, Nasr Alkadi, J. Kelly Kissock

Mechanical and Aerospace Engineering Faculty Publications

The automotive industry is the largest industry in the United States in terms of the dollar value of production [1]. U.S. automakers face tremendous pressure from foreign competitors, which have an increasing manufacturing presence in this country. The Big Three North American Original Equipment Manufacturers (OEMs)-General Motors, Ford, and Chrysler-are reacting to declining sales figures and economic strain by working more efficiently and seeking out opportunities to reduce production costs without negatively affecting the production volume or the quality of the product. Successful, cost-effective investment and implementation of the energy efficiency technologies and practices meet the challenge of maintaining the …


Contextual Detection Of Anomalies In Hyperspectral Images, Adam J. Messer Mar 2011

Contextual Detection Of Anomalies In Hyperspectral Images, Adam J. Messer

Theses and Dissertations

The majority of anomaly detectors in Hyperspectral Imaging use only the statistical aspects of the spectral readings in the image. These detectors fail to use the spatial context that is contained in the images. The use of this information can yield detectors that out perform their spatially myopic counterparts. To demonstrate this, we will use an independent component analysis based detector, autonomous global anomaly detector (AutoGAD), developed at AFIT augmented to account for the spatial context of the detected anomalies. Through the use of segmentation algorithms, the anomalies identified are formed into regions. The size and shape of these regions …


Empirical Characterization Of Ballistic Impact Flash, Thomas P. Talafuse Mar 2011

Empirical Characterization Of Ballistic Impact Flash, Thomas P. Talafuse

Theses and Dissertations

Fires onboard aircraft are leading mechanisms for mishaps and losses during peacetime and combat operations. Typical ignition sources causing fires onboard aircraft include electrical sparks and hot surfaces. However, impact and penetration of common threats encountered during combat operations, such as armor piercing incendiary projectiles and missile fragments, generate short-lived, but thermally-intense clouds (flashes) capable of igniting fires. Fire simulations supporting system-level survivability analyses depend on accurate characterization of these flash clouds, however, such accurate representations are not currently available. This research presents the modeling approach developed to estimate the boundary model representations of impact flashes. The research presents generalized …


A Methodology Using Simulation Results For Test And Evaluation, Jonathon S. Hosket Mar 2011

A Methodology Using Simulation Results For Test And Evaluation, Jonathon S. Hosket

Theses and Dissertations

Each year the Air Force spends billions of dollars on Test and Evaluation to ensure acquisition programs roll out the best possible products. In 1997, the National Research Council assembled to evaluate the overall procedure used in procuring various platforms with system planning, research, development and engineering (SPRDE) and program management (PM) processes. In their final report, they claimed that the full advantages of statistical practices, simulation, model-test-models, and incorporation of prior test information into current test practices have not been fully utilized. To examine one of the report's recommendations, this thesis defines and explores a methodology using simulation to …


Weighted Key Player Problem For Social Network Analysis, Ryan M. Mcguire Mar 2011

Weighted Key Player Problem For Social Network Analysis, Ryan M. Mcguire

Theses and Dissertations

Social network analysis is a tool set whose uses range from measuring the impact of marketing campaigns to disrupting clandestine terrorist organizations. Social network analysis tools are primarily focused on the structure of relationships between actors in the network. However, characteristics of the actors, such as importance or status, are generally the output of the social network analysis rather than an input. Characteristics of actors can come from a number of sources to include information gathering, subject matter experts or social network analysis. Further, the strength of relationships between actors in social networks are often assumed to be all equal. …


Optimizing Ground Times For Amc Aircraft In Afghanistan, Eric W. Bucheit Jr. Mar 2011

Optimizing Ground Times For Amc Aircraft In Afghanistan, Eric W. Bucheit Jr.

Theses and Dissertations

This research provides insight into the cargo unloading and loading process and times at three airfields in Afghanistan. Using a linear regression model and its prediction capability, a more stabilized environment is produced. This uses the times from seven historical months of continuous operations in Afghanistan and uses this information for the prediction expressions. Using this model, no throughput is lowered and early and late times are lowered by an average of seven minutes per mission. Over the course of a month, this increases planning stability by 74.1 hours. This not only impacts the planning at the downrange location, but …


Tailoring The Statistical Experimental Design Process For Lvc Experiments, Casey L. Haase Mar 2011

Tailoring The Statistical Experimental Design Process For Lvc Experiments, Casey L. Haase

Theses and Dissertations

The use of Live, Virtual and Constructive (LVC) Simulation environments are increasingly being examined for potential analytical use particularly in test and evaluation. The LVC simulation environments provide a mechanism for conducting joint mission testing and system of systems testing when scale and resource limitations prevent the accumulation of the necessary density and diversity of assets required for these complex and comprehensive tests. The statistical experimental design process is re-examined for potential application to LVC experiments and several additional considerations are identified to augment the experimental design process for use with LVC. This augmented statistical experimental design process is demonstrated …


Determining Pilot Manning For Bomber Longevity, Jason S. Hamilton Mar 2011

Determining Pilot Manning For Bomber Longevity, Jason S. Hamilton

Theses and Dissertations

In support of US Air Force efforts to conserve resources without sacrificing capability, this research examines the question of whether the 509th Bomb Wing could continue to provide maximum combat capability with fewer assigned pilots. During peacetime, pilot proficiency training comprises the majority of annual flying hours for the small B-2 bomber fleet. Optimal pilot manning will decrease the accumulation of excess wear on the airframes; helping to extend the viable life of the B-2 fleet and preserve the deterrent and combat capabilities that it provides to the United States. The operations and maintenance activity flows for B-2 aircraft and …


Measure Of Effectiveness For Jstars Ground Moving Target Indicator: A Value Focused Thinking Approach, Gardner J. Joyner Mar 2011

Measure Of Effectiveness For Jstars Ground Moving Target Indicator: A Value Focused Thinking Approach, Gardner J. Joyner

Theses and Dissertations

As the nature of warfare has shifted from a conventional approach to more guerilla type warfare, intelligence has become more important than at any other time in the history of the United States Military. With the stochastic nature of intelligence gathering, it is almost impossible to know with any degree of certainty where and when the next piece of information that could possibly change the course of the battle or war will be obtained. US intelligence gathering assets have long been plagued with using useless measures of performance rather than measures of effectiveness to determine their worth. This research uses …