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Modeling Systems For Optimal Resource Allocation, Scheduling, And Decision Making, Esengul Tayfur Aug 2008

Modeling Systems For Optimal Resource Allocation, Scheduling, And Decision Making, Esengul Tayfur

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This dissertation focuses on the resource requirements and scheduling problem for logistic systems. We investigate solutions to this problem in two different logistic systems: logistic system of the health care facilities during emergency evacuations and delivery and distribution system of production industries. All hospitals must have an evacuation plan to ensure the safety of patients and prevent the loss of life. However, hospital operators have not been able to quantify how resource availability, the cost of acquiring those resources, and evacuation completion time are related. This research addresses this problem and contributes two methodologies to solve this problem. In the …


Investigation Of A Photosynthetically Aerated Cathode In A Mfc, Derek Little Jul 2008

Investigation Of A Photosynthetically Aerated Cathode In A Mfc, Derek Little

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A microbial fuel cell (MFC) creates an environment that facilitates the conversion of electron donor compounds into electrical current through the oxidizing powers of microbial growth. Within the anode of a MFC bacteria grow oxidizing organic compounds while in the cathode oxygen is reduced. The goal of a MFC is to achieve respiration under anaerobic conditions having electrodes serve as intermediate electron acceptor for bacteria in the anode and shuttle electrons through a circuit to the cathode reducing a terminal electron acceptor.
Waste from the biological production of hydrogen from agricultural peach was explored for use within the anode of …


Optimization And Characterization Of Biodiesel Production From Cottonseed And Canola Oil, Hem Joshi Jun 2008

Optimization And Characterization Of Biodiesel Production From Cottonseed And Canola Oil, Hem Joshi

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Transesterification of cottonseed oil and canola oil was carried out using low molecular weight alcohols and potassium hydroxide. For cottonseed oil, a central composite design with eight factorial, six center and six axial points was used to study the effect of catalyst concentration, molar ratio of ethanol to cottonseed oil and reaction temperature on percentage yield and percentage initial absorbance (%A385nm) of the biodiesel. Catalyst concentration and molar ratio of ethanol to cottonseed oil were the most influential variables affecting percentage conversion and percentage initial absorbance. Maximum percentage yield of 98 % is predicted at a catalyst concentration of 1.07 …


Optimal Fleet Size Of An Integrated Production And Distribution Scheduling Problem For A Single Perishable Product, Priyantha Devapriya May 2008

Optimal Fleet Size Of An Integrated Production And Distribution Scheduling Problem For A Single Perishable Product, Priyantha Devapriya

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This dissertation focuses on a practical production problem in which a perishable product must be produced and distributed at minimum cost. The problem has some features of the integrated production and distribution scheduling problem in that we seek to determine the fleet size and their routes subject to a planning horizon constraint but there are significant differences as well. In particular, this research differs because the product has a limited lifetime, the total demand must be satisfied within a planning horizon, multiple trucks can be used, and the production schedule and the distribution sequence are considered. Two mixed integer programming …


Effect Of Nitrogen Filling On Tire Rolling Resistance And Vehicle Fuel Economy, Prakash Venkataraman Dec 2007

Effect Of Nitrogen Filling On Tire Rolling Resistance And Vehicle Fuel Economy, Prakash Venkataraman

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There are various losses associated with passenger vehicle that affect its fuel economy as it is being operated. These losses include engine, driveline, aerodynamic and rolling losses. While engine, driveline and aerodynamic losses are inherent with the vehicle due to large number of parts that go into assembling, rolling loss is associated with the vehicle tires and it is the only part of the vehicle that comes in contact with the road. The rolling resistance of inflated tires is an important component of resistance to vehicle motion and contributes to vehicle fuel consumption. Many research works have been focused on …


Heuristics For Scheduling Reentrant Flexible Job Shops With Sequence-Dependent Setup Times And Limited Buffer Capacities, Jakrawarn Kunadilok Aug 2007

Heuristics For Scheduling Reentrant Flexible Job Shops With Sequence-Dependent Setup Times And Limited Buffer Capacities, Jakrawarn Kunadilok

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This research addresses the problem of scheduling complex job shops with minimizing total weighted tardiness as the objective. The complex job shop is characterized by reentrant job flow through a number of different work centers that contain one or more identical parallel machines. The processing restrictions for the complex job shop include possible non-zero ready times and sequence-dependent setup times. We categorize the complex job shop into two classes: the complex job shop with infinite or finite buffer capacities. We propose three solution methodologies for scheduling the problem with infinite buffer capacities. The first method is the use of mixed …


Development Of Prediction Models To Measure Vendor Performance In Surveillance And Auditing Of Aircraft Maintenance, Nikhil Iyengar May 2007

Development Of Prediction Models To Measure Vendor Performance In Surveillance And Auditing Of Aircraft Maintenance, Nikhil Iyengar

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Elimination of aviation accidents is one of the primary goals of the Federal Aviation Administration (FAA) and the airline industry. A leading cause of aviation accidents is lack of oversight of various organizational issues, in particular, the organization's maintenance operation performance. The technologies used in the industry generate multiple risks, mostly from three domains: systems, hardware and people. Maintenance performance analyses identify the inherent risk in distributed, large-scale systems. Analysis of existing aviation maintenance data is a crucial step in meeting the aviation industry's need to improve aviation safety. Presently, we lack suitable tools to analyze large bodies of maintenance …


Models Of Semi-Systematic Visual Search, Sourav Das May 2007

Models Of Semi-Systematic Visual Search, Sourav Das

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Visual search is an important aspect of many examination and monitoring tasks. As a result, visual search performance has been the topic of many empirical investigations. These investigations have reported that individual search performance depends on subject factors such as search behavior, which has motivated the development of models of visual search that incorporate this behavior. Search behavior ranges from random to strictly systematic; variation in behavior is commonly assumed to be caused by differences in memory retrieval and search strategy. Accordingly, a mathematical model of semi-systematic search is proposed here that can account for both memory retrieval and other …


Domination And Decomposition In Multiobjective Programming, Alexander Engau May 2007

Domination And Decomposition In Multiobjective Programming, Alexander Engau

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During the last few decades, multiobjective programming has received much attention for both its numerous theoretical advances as well as its continued success in modeling and solving real-life decision problems in business and engineering. In extension of the traditionally adopted concept of Pareto optimality, this research investigates the more general notion of domination and establishes various theoretical results that lead to new optimization methods and support decision making.
After a preparatory discussion of some preliminaries and a review of the relevant literature, several new findings are presented that characterize the nondominated set of a general vector optimization problem for which …


A Multidimensional Scaling And Participatory Design Approach To Classify Open Ended Aircraft Maintenance Data, Kunal Kapoor Dec 2006

A Multidimensional Scaling And Participatory Design Approach To Classify Open Ended Aircraft Maintenance Data, Kunal Kapoor

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The quality assurance data to be analyzed by the web-based surveillance and auditing tool (WebSAT) is both qualitative and quantitative. The forced responses to checklist questions provide a definitive outcome identifying the effectiveness of the four quality assurance work functions. On the other hand, open-ended responses, the second type of response for capturing maintenance errors, are qualitative in nature since they reflect what the auditors and quality assurance representatives observe during their interactions at vendor locations. This research proposes to apply the statistical technique of multidimensional scaling (MDS) and the User centered Design (UCD) method of Participatory Design (PD) to …


Use Of Personas For User Interface Design: Results Of Field And Experimental Studies , Pallavi Dharwada Dec 2006

Use Of Personas For User Interface Design: Results Of Field And Experimental Studies , Pallavi Dharwada

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Persona is a fictitious user serving as a role model for designers, helping them make difficult decisions from the users' perspective during the interface design process. This concept, which was introduced by Alan Cooper in 1999, has been found to be a powerful tool for engaging the designers with the users. Although personas do not replace the rich data acquired through user testing, they enhance the interface development process by focusing the designers' attention on the target user until the interface qualifies for testing. Recognizing the benefits of persona, many companies, including the Fortune 500 have embraced this concept as …