+publisher:"Texas A&M University" +contributor:("Curry, Guy L.")

Texas A&M University

1. Katariya, Abhilasha. Optimal Allocation of Inventory and Demand for Managing Supply Chain Revenues.

Degree: PhD, Industrial Engineering, 2013, Texas A&M University

URL: http://hdl.handle.net/1969.1/151863

► This dissertation focuses on three distinct yet related problems that are motivated by practices of electronics manufacturers, who satisfy stochastic demand from multiple markets and… (more)

▼ This dissertation focuses on three distinct yet related problems that are motivated by practices of electronics manufacturers, who satisfy stochastic demand from multiple markets and multisource parts from several suppliers. The first problem investigates joint replenishment and allocation decisions for a supplier who satisfies stochastic demand from a primary market and a spot market. We formulate the problem as a multi-period stochastic dynamic program and show that the optimal policy is characterized by two quantities: the critical produce-up-to level and the critical retain-up-to level. We establish bounds for these two quantities, discuss their economic interpretation, and use them to construct a new and effective heuristic policy. We identify two practical benchmark policies and establish thresholds on the unit revenue earned from the spot market such that one of the two benchmark policies is optimal. Using a computational study, we quantify the benefits of the optimal policy relative to the benchmark policies and examine the effects of demand correlation. The second problem investigates an important extension where a supplier faces stochas- tic demand from Class 1 along with price-sensitive stochastic demand from Class 2. We investigate the supplier’s joint replenishment, allocation and pricing problem by formulating it as a multi-period, two-stage stochastic dynamic program. We show that a dynamic pricing policy is optimal at stage 2, and the stage 1 optimal policy is characterized by two quantities: the critical produce-up-to level and the critical amount of inventory to be protected from Class 1. In contrast to the optimal policy, myopic policies are less costly to evaluate, and hence, are more practical. We establish two sufficient conditions under which a myopic joint inventory and pricing policy is optimal. Using a computational study, we show that the benefits of dynamic pricing to Class 2 are higher than the benefits of discretionary sales to Class 1. While the first two problems consider a supplier’s decision under stochastic demand from multiple markets, the third problem considers decisions of a buyer who satisfies stochastic demand by multi-sourcing parts with percentage supply allocations (PSAs). We define PSA as a pre-negotiated percentage of a multi-sourced part’s total demand that the buyer should allocate to a supplier. During recent industry collaboration, we observed that in such settings the buyer’s demand allocation decisions are challenging due to operational changes needed for (temporarily) switching suppliers, and lead to the bullwhip effect. Demand allocation policies that can meet PSAs and the resulting bullwhip effect have not been investigated in the literature before. We contribute to the existing literature by introducing and analyzing the concept of bullwhip effect under multi-sourcing. In addition, we propose and investigate three demand allocation policies: (i) random allocation policy (RAP), which benchmarks the current practice, (ii) time-based (CCP-T) and (iii)… Advisors/Committee Members: Cetinkaya, Sila (advisor), Tekin, Eylem (advisor), Curry, Guy L (committee member), Sriskandarajah, Chelliah (committee member).

Subjects/Keywords: Inventory/production systems; production capacity; spot market; stochastic dynamic programming; dynamic pricing; myopic policies; replenishment; inventory allocation; demand allocation; bullwhip effect; cyclic consumption policy; multi-sourcing; multiple markets

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APA (6^th Edition):

Katariya, A. (2013). Optimal Allocation of Inventory and Demand for Managing Supply Chain Revenues. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/151863

Chicago Manual of Style (16^th Edition):

Katariya, Abhilasha. “Optimal Allocation of Inventory and Demand for Managing Supply Chain Revenues.” 2013. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/151863.

MLA Handbook (7^th Edition):

Katariya, Abhilasha. “Optimal Allocation of Inventory and Demand for Managing Supply Chain Revenues.” 2013. Web. 11 Apr 2021.

Vancouver:

Katariya A. Optimal Allocation of Inventory and Demand for Managing Supply Chain Revenues. [Internet] [Doctoral dissertation]. Texas A&M University; 2013. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/151863.

Council of Science Editors:

Katariya A. Optimal Allocation of Inventory and Demand for Managing Supply Chain Revenues. [Doctoral Dissertation]. Texas A&M University; 2013. Available from: http://hdl.handle.net/1969.1/151863

Texas A&M University

2. Dalal, Jyotirmoy. Models and Solution Approaches for Emergency Response Network Design Integrating Supply and Demand Sides.

Degree: PhD, Industrial Engineering, 2014, Texas A&M University

URL: http://hdl.handle.net/1969.1/154088

► We present three models for emergency response network design. First, in a deterministic setting, we focus on two critical aspects of emergency logistics: evacuation and… (more)

▼ We present three models for emergency response network design. First, in a deterministic setting, we focus on two critical aspects of emergency logistics: evacuation and relief distribution. We consider a three-tier system comprising evacuation sources, shelters, and distribution centers (DC). Applying a multi-objective mixed integer programming model, we minimize the evacuees’ maximum travel distance and total system cost. To solve large scale instances, we implement Benders Decomposition (BD) with callback feature, solving the master problem only once, thereby, saving significant solution time. We also find that tuning of master tree search parameters along with strengthening of the Benders cuts, impact convergence significantly. Next, our model is applied to a GIS-based case study on coastal Texas. We find the effects of changing problem parameters and explain the cost vs. critical distance trade-offs. We conclude that our proposed system works better than the system in practice by comparing them and by providing interesting managerial insights on location decision. In the second study, for a more detailed network comprising five tiers and multiple modes of transport, we determine the centralized supply locations that serve the region under consideration under any disaster event. Using scenario and interval based representations together, we address uncertainties (1) in disaster location, intensity, and duration, and (2) in demand due to varied compliance rate of the population to the authority’s orders. We efficiently solve the large scale instances using a decomposition-based approach. The model is applied to a case study on the Gulf coast of the USA. We find the effects of population density and disaster intensity on location-allocation decisions. Our model captures the trade-offs between system cost and critical time to start relief distribution, and can aid an emergency manager in strategic decision making under various uncertainties. Our third study combines the stochastic and robust optimization concepts. Disaster intensity and location related uncertainties are represented by a discrete scenario set. In a problem setting similar to our first study, the DC and shelter opening costs, and the weighted sum of the worst case (robust optimization) and expected (stochastic optimization) flow costs are minimized over all scenarios. We present Benders Decomposition based solution approaches to solve the model with different relative weight vectors. We conduct a case study on coastal Texas and observe the effects of changing certain problem parameters. We find that the underlying demand pattern dictates whether placing the relative emphasis on worst and average cases would alter the location decisions. Our model allows the decision maker to explore several alternatives by changing the emphasis on worst vs. average case cost minimization. Advisors/Committee Members: Uster, Halit (advisor), Curry, Guy L. (advisor), Cetinkaya, Sila (committee member), Geismar, Neil (committee member).

Subjects/Keywords: Humanitarian Logistics; Integrated Network; Emergency Response; Robust Optimization; Uncertainty; Multi-objective Optimization; Benders Decomposition; GIS.

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APA (6^th Edition):

Dalal, J. (2014). Models and Solution Approaches for Emergency Response Network Design Integrating Supply and Demand Sides. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/154088

Chicago Manual of Style (16^th Edition):

Dalal, Jyotirmoy. “Models and Solution Approaches for Emergency Response Network Design Integrating Supply and Demand Sides.” 2014. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/154088.

MLA Handbook (7^th Edition):

Dalal, Jyotirmoy. “Models and Solution Approaches for Emergency Response Network Design Integrating Supply and Demand Sides.” 2014. Web. 11 Apr 2021.

Vancouver:

Dalal J. Models and Solution Approaches for Emergency Response Network Design Integrating Supply and Demand Sides. [Internet] [Doctoral dissertation]. Texas A&M University; 2014. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/154088.

Council of Science Editors:

Dalal J. Models and Solution Approaches for Emergency Response Network Design Integrating Supply and Demand Sides. [Doctoral Dissertation]. Texas A&M University; 2014. Available from: http://hdl.handle.net/1969.1/154088

Texas A&M University

3. Harputlu, Emrah 1986-. A Human Performance Modeling System for Process Safety Operations.

Degree: MS, Chemical Engineering, 2013, Texas A&M University

URL: http://hdl.handle.net/1969.1/149226

► Operators have a crucial role in case of an emergency in a process facility. When an abnormality occurs in the process, the operator has a… (more)

▼ Operators have a crucial role in case of an emergency in a process facility. When an abnormality occurs in the process, the operator has a limited time to take corrective actions before system safety devices shut down the operation. It is crucial that system designers and safety professionals know about this required time frame before operations are initiated. Specific research goals for this project include the following: * Estimating the standard time data for operators to take corrective actions in emergency situations. * Developing a modeling system, to allow design/process engineers to find the standard time required for the operator(s) to respond in emergency situations. Current standard time data for carrying out tasks cover normal, steady state cases. However, the time required to take action in emergency situations is different than normal cases. Because of the possibility of a process incident and danger, operators make corrective actions faster compared to normal cases. Therefore, current standard time data do not meet the requirement for emergency situations. Shorter standard time data for emergency situations needs to be estimated. Standard time data for emergency situations is estimated by using time studies. Various time study methods were introduced and discussed. MODAPTS is a predetermined time standard method and stands for Modular Arrangement of Predetermined Time Standards, and was used in this project because it is reliable, easy to use and consistent. The methodology adopted for the study required observing several emergency case videos. The operations were decomposed into basic motions (such as walking, hand movement, bend and arise, etc.) by using a video player’s frame by frame feature. The amount of time required to take these basic motions was estimated. These estimated times were then compared to calculations based on MODAPTS, which is a predetermined time standard system. By comparing MODAPTS’s standard time intervals with those estimated from emergency situations, ratios or coefficients have been estimated for the various basic motions (e.g., factors such as 0.9, 0.75, etc.). The estimated coefficients for emergency situations, which are generally around 0.65, were used in developing a modeling system. The user of this modeling system can estimate the required time to take corrective actions in emergency situations as long as he/ she knows the actions need to be taken. Consequently, the time required to take necessary actions in emergency operations will be designed and evaluated in a systematic way to reduce the potential, as well as duration, of an incident. Advisors/Committee Members: Mannan, Sam M (advisor), El-Halwagi, Mahmoud M (committee member), Curry, Guy L (committee member).

Subjects/Keywords: human factors; standard data; Human performance

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APA (6^th Edition):

Harputlu, E. 1. (2013). A Human Performance Modeling System for Process Safety Operations. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/149226

Chicago Manual of Style (16^th Edition):

Harputlu, Emrah 1986-. “A Human Performance Modeling System for Process Safety Operations.” 2013. Masters Thesis, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/149226.

MLA Handbook (7^th Edition):

Harputlu, Emrah 1986-. “A Human Performance Modeling System for Process Safety Operations.” 2013. Web. 11 Apr 2021.

Vancouver:

Harputlu E1. A Human Performance Modeling System for Process Safety Operations. [Internet] [Masters thesis]. Texas A&M University; 2013. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/149226.

Council of Science Editors:

Harputlu E1. A Human Performance Modeling System for Process Safety Operations. [Masters Thesis]. Texas A&M University; 2013. Available from: http://hdl.handle.net/1969.1/149226

Texas A&M University

4. Lakshmipathy, Sathish Kumar. VHTR Core Shuffling Algorithm Using Particle Swarm Optimization ReloPSO-3D.

Degree: MS, Nuclear Engineering, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11188

► Improving core performance by reshuffling/reloading the fuel blocks within the core is one of the in-core fuel management methods with two major benefits: a possibility… (more)

▼ Improving core performance by reshuffling/reloading the fuel blocks within the core is one of the in-core fuel management methods with two major benefits: a possibility to improve core life and increase core safety. VHTR is a hexagonal annular core reactor with reflectors in the center and outside the fuel rings (3-rings). With the block type fuel assemblies, there is an opportunity for muti-dimensional fuel bocks movement within the core during scheduled reactor refueling operations. As the core is symmetric, by optimizing the shuffle operation of 1/6th of the core, the same process can be repeated through the remaining 5/6th of the core. VHTR has 170 fuel blocks in the core of which 50 are control rod blocks and are not movable to regular fuel block locations. The reshuffling problem now is to find the best combination of 120 fuel blocks that has a minimized power peaking and/or increased core life under safety constraints among the 120! combinations. For evaluating each LP during the shuffling, a fitness function that is developed from the parameters affecting the power peaking and core life is required. Calculating the power peaking at each step using Monte Carlo simulations on a whole core exact geometry model is a time consuming process and not feasible. A parameter is developed from the definitions of reactivity and power peaking factor called the localized reactivity potential that can be estimated for every block movement based on the reaction rates and atom densities of the initial core burnup at the time of shuffling. The algorithm (ReloPSO) is based on Particle Swarm Optimization algorithm the search process by improving towards the optimum from a set of random LPs based on the fitness function developed with the reactivity potential parameter. The algorithm works as expected and the output obtained has a flatter reactivity profile than the input. The core criticality is found to increase when shuffled closer to end of life. Detailed analysis on the burn runs after shuffling at different time of core operation is required to correlate the estimated and actual values of the reactivity parameter and to optimize the time of shuffle. Advisors/Committee Members: Tsvetkov, Pavel V. (advisor), Hassan, Yassin A. (committee member), Curry, Guy L. (committee member).

Subjects/Keywords: Particle Swarm Optimization; Core shuffling optimization

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APA (6^th Edition):

Lakshmipathy, S. K. (2012). VHTR Core Shuffling Algorithm Using Particle Swarm Optimization ReloPSO-3D. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11188

Chicago Manual of Style (16^th Edition):

Lakshmipathy, Sathish Kumar. “VHTR Core Shuffling Algorithm Using Particle Swarm Optimization ReloPSO-3D.” 2012. Masters Thesis, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11188.

MLA Handbook (7^th Edition):

Lakshmipathy, Sathish Kumar. “VHTR Core Shuffling Algorithm Using Particle Swarm Optimization ReloPSO-3D.” 2012. Web. 11 Apr 2021.

Vancouver:

Lakshmipathy SK. VHTR Core Shuffling Algorithm Using Particle Swarm Optimization ReloPSO-3D. [Internet] [Masters thesis]. Texas A&M University; 2012. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11188.

Council of Science Editors:

Lakshmipathy SK. VHTR Core Shuffling Algorithm Using Particle Swarm Optimization ReloPSO-3D. [Masters Thesis]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11188

Texas A&M University

5. Wang, Yaping. Matching Misaligned Two-Resolution Metrology Data.

Degree: PhD, Industrial Engineering, 2016, Texas A&M University

URL: http://hdl.handle.net/1969.1/158076

► Multi-resolution metrology devices co-exist in today's manufacturing environment, producing coordinate measurements complementing each other. Typically, the high-resolution device produces a scarce but accurate dataset, whereas… (more)

▼ Multi-resolution metrology devices co-exist in today's manufacturing environment, producing coordinate measurements complementing each other. Typically, the high-resolution device produces a scarce but accurate dataset, whereas the low-resolution one produces a dense but less accurate dataset. Research has shown that combining the two datasets of different resolutions makes better predictions of the geometric features of a manufactured part. A challenge, however, is how to effectively match each high-resolution data point to a low-resolution point that measures approximately the same physical location. A solution to this matching problem appears a prerequisite to a good final prediction. This dissertation solves this metrology matching problem by formulating it as a quadratic integer programming, aiming at minimizing the maximum inter-point-distance difference (maxIPDdiff) among all potential correspondences. Due to the combinatorial nature of the optimization model, solving it to optimality is computationally prohibitive even for a small problem size. In order to solve real-life sized problems within a reasonable amount of time, a two-stage matching framework (TSMF) is proposed. The TSMF approach follows a coarse-to-fine search strategy and consists of down-sampling the full size problem, solving the down-sampled problem to optimality, extending the solution of the down-sampled problem to the full size problem, and refining the solution using iterative local search. Many manufactured parts are designed with symmetric features; that is, many part surfaces are invariant (are mapped to themselves) to certain intrinsic reflections and/or rotations. Dealing with parts surfaces with symmetric features makes the metrology matching problem even more challenging. The new challenge is that, due to this symmetry, alignment performance metrics such as maxIPDdiff and root mean square error are not able to differentiate between (a) correct solutions/correspondences that are orientationally consistent with the underlying true correspondences and (b) incorrect but seemingly correct solutions that can be obtained by applying the surface's intrinsic reflections and/or rotations to a correct set of correspondences. To address this challenge, a filtering procedure is proposed to supplement the TSMF approach. Specifically, the filtering procedure works by generating a solution pool that contains a group of plausible candidate sets of correspondences and subsequently filtering this pool in order to select a correct set of correspondences from the pool. Numerical experiments show that the TSMF approach outperforms two widely-used point set registration alternatives, the iterative closest point (ICP) and coherent point drift methods (CPD), in terms of several performance metrics. Moreover, compared to ICP and CPD, the TSMF approach scales very well as the instance size increases, and is robust with respect to the initial misalignment degree between the two datasets. The numerical results also show that, when enhanced with the proposed… Advisors/Committee Members: Moreno-Centeno, Erick (advisor), Ding, Yu (committee member), Curry, Guy L. (committee member), Sarin, Vivek (committee member).

Subjects/Keywords: Coordinate measuring machine; correspondences; iterative closest point (ICP); coherent point drift (CPD); two-stage matching framework; quadratic integer programming; rigid point set registration

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wang, Y. (2016). Matching Misaligned Two-Resolution Metrology Data. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/158076

Chicago Manual of Style (16^th Edition):

Wang, Yaping. “Matching Misaligned Two-Resolution Metrology Data.” 2016. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/158076.

MLA Handbook (7^th Edition):

Wang, Yaping. “Matching Misaligned Two-Resolution Metrology Data.” 2016. Web. 11 Apr 2021.

Vancouver:

Wang Y. Matching Misaligned Two-Resolution Metrology Data. [Internet] [Doctoral dissertation]. Texas A&M University; 2016. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/158076.

Council of Science Editors:

Wang Y. Matching Misaligned Two-Resolution Metrology Data. [Doctoral Dissertation]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/158076

Texas A&M University

6. Li, Ang. Optimal Screening for Preclinical Diseases.

Degree: PhD, Industrial and Systems Engineering, 2014, Texas A&M University

URL: http://hdl.handle.net/1969.1/152571

► Certain diseases comprise an initial asymptomatic period during which they can be identified only by a screening test. In many such cases, early detection translates… (more)

Subjects/Keywords: policy modeling and public sector operations research; asymptomatic disease screening; natural history model; stochastic models; nonlinear optimization

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Li, A. (2014). Optimal Screening for Preclinical Diseases. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/152571

Chicago Manual of Style (16^th Edition):

Li, Ang. “Optimal Screening for Preclinical Diseases.” 2014. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/152571.

MLA Handbook (7^th Edition):

Li, Ang. “Optimal Screening for Preclinical Diseases.” 2014. Web. 11 Apr 2021.

Vancouver:

Li A. Optimal Screening for Preclinical Diseases. [Internet] [Doctoral dissertation]. Texas A&M University; 2014. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/152571.

Council of Science Editors:

Li A. Optimal Screening for Preclinical Diseases. [Doctoral Dissertation]. Texas A&M University; 2014. Available from: http://hdl.handle.net/1969.1/152571

Texas A&M University

7. Wei, Bo. Stochastic Clearing Models with Applications in Shipment Consolidation.

Degree: PhD, Industrial Engineering, 2014, Texas A&M University

URL: http://hdl.handle.net/1969.1/153865

► This dissertation focuses on the average cost and service performance models in the shipment consolidation setting, which is treated as an application of stochastic clearing… (more)

Subjects/Keywords: Stochastic Clearing Models; Shipment Consolidation

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wei, B. (2014). Stochastic Clearing Models with Applications in Shipment Consolidation. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/153865

Chicago Manual of Style (16^th Edition):

Wei, Bo. “Stochastic Clearing Models with Applications in Shipment Consolidation.” 2014. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/153865.

MLA Handbook (7^th Edition):

Wei, Bo. “Stochastic Clearing Models with Applications in Shipment Consolidation.” 2014. Web. 11 Apr 2021.

Vancouver:

Wei B. Stochastic Clearing Models with Applications in Shipment Consolidation. [Internet] [Doctoral dissertation]. Texas A&M University; 2014. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/153865.

Council of Science Editors:

Wei B. Stochastic Clearing Models with Applications in Shipment Consolidation. [Doctoral Dissertation]. Texas A&M University; 2014. Available from: http://hdl.handle.net/1969.1/153865

Texas A&M University

8. Moya, Hiram. Border Crossing Modeling and Analysis: A Non-Stationary Dynamic Reallocation Methodology For Terminating Queueing Systems.

Degree: PhD, Industrial Engineering, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11772

► The United States international land boundary is a volatile, security intense area. In 2010, the combined trade was $918 billion within North American nations, with… (more)

▼ The United States international land boundary is a volatile, security intense area. In 2010, the combined trade was $918 billion within North American nations, with 80% transported by commercial trucks. Over 50 million commercial vehicles cross the Texas/Mexico border every year, not including private vehicles and pedestrian traffic, between Brownsville and El Paso, Texas, through one of over 25 major border crossings called "ports of entry" (POE). Recently, securing our southwest border from terrorist interventions, undocumented immigrants, and the illegal flow of drugs and guns has dominated the need to efficiently and effectively process people, goods and traffic. Increasing security and inspection requirements are seriously affecting transit times. Each POE is configured as a multi-commodity, prioritized queueing network which rarely, if ever, operates in steady-state. Therefore, the problem is about finding a balance between a reduction of wait time and its variance, POE operation costs, and the sustainment of a security level. The contribution of the dissertation is three-fold. The first uses queueing theory on the border crossing process to develop a methodology that decreases border wait times without increasing costs or affecting security procedures. The outcome is the development of the Dynamic Reallocation Methodology (DRM). Currently at the POE, inspection stations are fixed and can only inspect one truck type, FAST or Non-FAST program participant. The methodology proposes moveable servers that once a threshold is met, can be switched to service the other type of truck. Particular emphasis is given to inspection (service) times under time-varying arrivals (demands). The second contribution is an analytical model of the POE, to analyze the effects of the DRM. First assuming a Markovian service time, DRM benefits are evaluated. However, field data and other research suggest a general distribution for service time. Therefore, a Coxian k-phased approximation is implemented. The DRM is analyzed under this new baseline using expected number in the system, and cycle times. A variance reduction procedure is also proposed and evaluated under DRM. Results show that queue length and wait time is reduced 10 to 33% depending on load, while increasing FAST wait time by less than three minutes. Advisors/Committee Members: Curry, Guy L. (advisor), Arreola-Risa, Antonio (committee member), Feldman, Richard M. (committee member), Phillips, Don T. (committee member).

Subjects/Keywords: Queueing Theory; Border Crossing Process; Homeland Security; POE model; Optimization; Simulation; Supply Chain Management; Dynamic Reallocation Methodology; Port of Entry; Commercial Border Crossing; FAST; BOTA; NAFTA

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APA (6^th Edition):

Moya, H. (2012). Border Crossing Modeling and Analysis: A Non-Stationary Dynamic Reallocation Methodology For Terminating Queueing Systems. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11772

Chicago Manual of Style (16^th Edition):

Moya, Hiram. “Border Crossing Modeling and Analysis: A Non-Stationary Dynamic Reallocation Methodology For Terminating Queueing Systems.” 2012. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11772.

MLA Handbook (7^th Edition):

Moya, Hiram. “Border Crossing Modeling and Analysis: A Non-Stationary Dynamic Reallocation Methodology For Terminating Queueing Systems.” 2012. Web. 11 Apr 2021.

Vancouver:

Moya H. Border Crossing Modeling and Analysis: A Non-Stationary Dynamic Reallocation Methodology For Terminating Queueing Systems. [Internet] [Doctoral dissertation]. Texas A&M University; 2012. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11772.

Council of Science Editors:

Moya H. Border Crossing Modeling and Analysis: A Non-Stationary Dynamic Reallocation Methodology For Terminating Queueing Systems. [Doctoral Dissertation]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11772

Texas A&M University

9. Zhang, Yi. Inventory Control for Remanufacturing with Batch Processing, Seed Stock Planning, and Coordination Considerations.

Degree: PhD, Industrial Engineering, 2015, Texas A&M University

URL: http://hdl.handle.net/1969.1/156126

► In recent years, the general area of remanufacturing has received significant attention both in academia and practice. While there is a growing body of literature… (more)

▼ In recent years, the general area of remanufacturing has received significant attention both in academia and practice. While there is a growing body of literature in production planning models for remanufacturing, there is still a need for analytical decision-making tools considering general cost/revenue structures, stochastic demands, stochastic returns, and multiple agents/decision makers. Of particular interest in this dissertation are inventory control models with batch processing, seed stock planning, and coordination considerations for efficient inventory control practices. More specifically we investigate three distinct, yet related, inventory control problems: (1) a fundamental inventory and production planning problem arising in a batch processing environment for a third party remanufacturer, which is characterized by a stochastic used-item return process along with a stochastic remanufactured item demand process; (2) a seed stock planning problem in a batch processing environment with two agents including an original equipment manufacturer (OEM) and a remanufacturing supplier (RS), for which three game-theoretic scenarios and two types of controls are investigated; (3) a channel coordination problem in the reverse supply chain, which generalizes the above two problems in the sense that the stochastic nature of returns is modeled in a batch processing environment for channel coordination purposes. Our analytical decision-making models contribute to the existing literature in the following ways: (1) we investigate the impact of more general cost structures (including both fixed operational costs and inventory-related costs) and disposal options in a batch processing environment with stochastic demand and return; (2) we systematically study seed stock planning issues in a batch processing environment for remanufacturing using the game-theoretic framework; and (3) we build an analytical framework for channel coordination mechanism design for the reverse supply chain in a stochastic environment. Advisors/Committee Members: Cetinkaya, Sila (advisor), Curry, Guy L. (advisor), Klutke, Georgia-Ann (committee member), Cline, Daren B.H. (committee member).

Subjects/Keywords: Batch Processing; Seed Stock Planning; Channel Coordination

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APA (6^th Edition):

Zhang, Y. (2015). Inventory Control for Remanufacturing with Batch Processing, Seed Stock Planning, and Coordination Considerations. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/156126

Chicago Manual of Style (16^th Edition):

Zhang, Yi. “Inventory Control for Remanufacturing with Batch Processing, Seed Stock Planning, and Coordination Considerations.” 2015. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/156126.

MLA Handbook (7^th Edition):

Zhang, Yi. “Inventory Control for Remanufacturing with Batch Processing, Seed Stock Planning, and Coordination Considerations.” 2015. Web. 11 Apr 2021.

Vancouver:

Zhang Y. Inventory Control for Remanufacturing with Batch Processing, Seed Stock Planning, and Coordination Considerations. [Internet] [Doctoral dissertation]. Texas A&M University; 2015. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/156126.

Council of Science Editors:

Zhang Y. Inventory Control for Remanufacturing with Batch Processing, Seed Stock Planning, and Coordination Considerations. [Doctoral Dissertation]. Texas A&M University; 2015. Available from: http://hdl.handle.net/1969.1/156126

Texas A&M University

10. Eren, Ezgi. Stochastic Modeling and Analysis of Plant Microtubule System Characteristics.

Degree: PhD, Industrial Engineering, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11085

► In this dissertation, we consider a complex biological system known as cortical microtubule (CMT) system, where stochastic dynamics of the components (i.e., the CMTs) are… (more)

▼ In this dissertation, we consider a complex biological system known as cortical microtubule (CMT) system, where stochastic dynamics of the components (i.e., the CMTs) are defined in both space and time. CMTs have an inherent spatial dimension of their own, as their length changes over time in addition to their location. As a result of their dynamics in a confined space, they run into and interact with each other according to simple stochastic rules. Over time, CMTs acquire an ordered structure that is achieved without any centralized control beginning with a completely disorganized system. It is also observed that this organization might be distorted, when parameters of dynamicity and interactions change due to genetic mutation or environmental conditions. The main question of interest is to explore the characteristics of this system and the drivers of its self-organization, which is not feasible relying solely on biological experiments. For this, we replicate the system dynamics and interactions using computer simulations. As the simulations successfully mimic the organization seen in plant cells, we conduct an extensive analysis to discover the effects of dynamics and interactions on system characteristics by experimenting with different input parameters. To compare simulation results, we characterize system properties and quantify organization level using metrics based on entropy, average length and number of CMTs in the system. Based on our findings and conjectures from simulations, we develop analytical models for more generalized conclusions and efficient computation of system metrics. As a fist step, we formulate a mean-field model, which we use to derive sufficient conditions for organization to occur in terms of input parameters. Next, considering the parameter ranges that satisfy these conditions, we develop predictive methodologies for estimation of expected average length and number of CMTs over time, using a fluid model, transient analysis, and approximation algorithms tailored to our problem. Overall, we build a comprehensive framework for analysis and control of microtubule organization in plant cells using a wide range of models and methodologies in conjunction. This research also has broader impacts related to the fields of bio-energy, healthcare, and nanotechnology; in addition to its methodological contribution to stochastic modeling of systems with high-level spatial and temporal complexity. Advisors/Committee Members: Gautam, Natarajan (advisor), Curry, Guy L. (committee member), Feldman, Richard M. (committee member), Yurttas, Salih (committee member), Dixit, Ram (committee member).

Subjects/Keywords: fluid queues; mean-field theory; simulation; spatio-temporal bio-processes; plant cell cortical microtubules

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APA (6^th Edition):

Eren, E. (2012). Stochastic Modeling and Analysis of Plant Microtubule System Characteristics. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11085

Chicago Manual of Style (16^th Edition):

Eren, Ezgi. “Stochastic Modeling and Analysis of Plant Microtubule System Characteristics.” 2012. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11085.

MLA Handbook (7^th Edition):

Eren, Ezgi. “Stochastic Modeling and Analysis of Plant Microtubule System Characteristics.” 2012. Web. 11 Apr 2021.

Vancouver:

Eren E. Stochastic Modeling and Analysis of Plant Microtubule System Characteristics. [Internet] [Doctoral dissertation]. Texas A&M University; 2012. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11085.

Council of Science Editors:

Eren E. Stochastic Modeling and Analysis of Plant Microtubule System Characteristics. [Doctoral Dissertation]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11085

Texas A&M University

11. Mekaroonreung, Maethee. Production Economics Modeling and Analysis of Polluting firms: The Production Frontier Approach.

Degree: PhD, Industrial Engineering, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11724

► As concern grows about energy and environment issues, energy and environmental modeling and related policy analysis are critical issues for today's society. Polluting firms such… (more)

▼ As concern grows about energy and environment issues, energy and environmental modeling and related policy analysis are critical issues for today's society. Polluting firms such as coal power plants play an important role in providing electricity to drive the U.S. economy as well as producing pollution that damages the environment and human health. This dissertation is intended to model and estimate polluting firms' production using nonparametric methods. First, frontier production function of polluting firms is characterized by weak disposability between outputs and pollutants to reflecting the opportunity cost to reduce pollutants. The StoNED method is extended to estimate a weak disposability frontier production function accounting for random noise in the data. The method is applied to the U.S. coal power plants under the Acid Rain Program to find the average technical inefficiency and shadow price of SO2 and NOx. Second, polluting firms' production processes are modeled characterizing both the output production process and the pollution abatement process. Using the law of conservation of mass applied to the pollution abatement process, this dissertation develops a new frontier pollutant function which then is used to find corresponding marginal abatement cost of pollutants. The StoNEZD method is applied to estimate a frontier pollutant function considering the vintage of capital owned by the polluting firms. The method is applied to estimate the average NOx marginal abatement cost for the U.S. coal power plants under the current Clean Air Interstate Rule NOx program. Last, the effect of a technical change on marginal abatement costs are investigated using an index decomposition technique. The StoNEZD method is extended to estimate sequential frontier pollutant functions reflecting the innovation in pollution reduction. The method is then applied to estimate a technical change effect on a marginal abatement cost of the U.S. coal power plants under the current Clean Air Interstate Rule NOx program. Advisors/Committee Members: Johnson, Andrew L. (advisor), Butenko, Sergiy (committee member), Curry, Guy L. (committee member), McCarl, Bruce A. (committee member).

Subjects/Keywords: Production economics; Frontier estimation; Nonparametric regression; Shadow pricing; Marginal abatement cost; Technical change

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APA (6^th Edition):

Mekaroonreung, M. (2012). Production Economics Modeling and Analysis of Polluting firms: The Production Frontier Approach. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11724

Chicago Manual of Style (16^th Edition):

Mekaroonreung, Maethee. “Production Economics Modeling and Analysis of Polluting firms: The Production Frontier Approach.” 2012. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11724.

MLA Handbook (7^th Edition):

Mekaroonreung, Maethee. “Production Economics Modeling and Analysis of Polluting firms: The Production Frontier Approach.” 2012. Web. 11 Apr 2021.

Vancouver:

Mekaroonreung M. Production Economics Modeling and Analysis of Polluting firms: The Production Frontier Approach. [Internet] [Doctoral dissertation]. Texas A&M University; 2012. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11724.

Council of Science Editors:

Mekaroonreung M. Production Economics Modeling and Analysis of Polluting firms: The Production Frontier Approach. [Doctoral Dissertation]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11724

Texas A&M University

12. Zhang, Yi. Inventory Control for Remanufacturing with Batch Processing, Seed Stock Planning, and Coordination Considerations.

Degree: PhD, Industrial Engineering, 2015, Texas A&M University

URL: http://hdl.handle.net/1969.1/156125

► In recent years, the general area of remanufacturing has received significant attention both in academia and practice. While there is a growing body of literature… (more)

▼ In recent years, the general area of remanufacturing has received significant attention both in academia and practice. While there is a growing body of literature in production planning models for remanufacturing, there is still a need for analytical decision-making tools considering general cost/revenue structures, stochastic demands, stochastic returns, and multiple agents/decision makers. Of particular interest in this dissertation are inventory control models with batch processing, seed stock planning, and coordination considerations for efficient inventory control practices. More specifically we investigate three distinct, yet related, inventory control problems: (1) a fundamental inventory and production planning problem arising in a batch processing environment for a third party remanufacturer, which is characterized by a stochastic used-item return process along with a stochastic remanufactured item demand process; (2) a seed stock planning problem in a batch processing environment with two agents including an original equipment manufacturer (OEM) and a remanufacturing supplier (RS), for which three game-theoretic scenarios and two types of controls are investigated; (3) a channel coordination problem in the reverse supply chain, which generalizes the above two problems in the sense that the stochastic nature of returns is modeled in a batch processing environment for channel coordination purposes. Our analytical decision-making models contribute to the existing literature in the following ways: (1) we investigate the impact of more general cost structures (including both fixed operational costs and inventory-related costs) and disposal options in a batch processing environment with stochastic demand and return; (2) we systematically study seed stock planning issues in a batch processing environment for remanufacturing using the game-theoretic framework; and (3) we build an analytical framework for channel coordination mechanism design for the reverse supply chain in a stochastic environment. Advisors/Committee Members: Cetinkaya, Sila (advisor), Curry, Guy L. (advisor), Klutke, Georgia-Ann (committee member), Cline, Daren B.H. (committee member).

Subjects/Keywords: Batch Processing; Seed Stock Planning; Channel Coordination

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APA (6^th Edition):

Zhang, Y. (2015). Inventory Control for Remanufacturing with Batch Processing, Seed Stock Planning, and Coordination Considerations. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/156125

Chicago Manual of Style (16^th Edition):

Zhang, Yi. “Inventory Control for Remanufacturing with Batch Processing, Seed Stock Planning, and Coordination Considerations.” 2015. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/156125.

MLA Handbook (7^th Edition):

Zhang, Yi. “Inventory Control for Remanufacturing with Batch Processing, Seed Stock Planning, and Coordination Considerations.” 2015. Web. 11 Apr 2021.

Vancouver:

Zhang Y. Inventory Control for Remanufacturing with Batch Processing, Seed Stock Planning, and Coordination Considerations. [Internet] [Doctoral dissertation]. Texas A&M University; 2015. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/156125.

Council of Science Editors:

Zhang Y. Inventory Control for Remanufacturing with Batch Processing, Seed Stock Planning, and Coordination Considerations. [Doctoral Dissertation]. Texas A&M University; 2015. Available from: http://hdl.handle.net/1969.1/156125

13. Yerasi, Pranavi. Productivity Improvement of a Manual Assembly Line.

Degree: MS, Industrial Engineering, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2011-08-10133

► The current project addresses the productivity improvement of a manual assembly line by making use of operations analysis in the framework of Lean production. A… (more)

Subjects/Keywords: Productivity Improvement; Manual Assembly line; Lean Production

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APA (6^th Edition):

Yerasi, P. (2012). Productivity Improvement of a Manual Assembly Line. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2011-08-10133

Chicago Manual of Style (16^th Edition):

Yerasi, Pranavi. “Productivity Improvement of a Manual Assembly Line.” 2012. Masters Thesis, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2011-08-10133.

MLA Handbook (7^th Edition):

Yerasi, Pranavi. “Productivity Improvement of a Manual Assembly Line.” 2012. Web. 11 Apr 2021.

Vancouver:

Yerasi P. Productivity Improvement of a Manual Assembly Line. [Internet] [Masters thesis]. Texas A&M University; 2012. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-08-10133.

Council of Science Editors:

Yerasi P. Productivity Improvement of a Manual Assembly Line. [Masters Thesis]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-08-10133

14. Kim, Pansoo. Near optimal design of fixture layouts in multi-station assembly processes.

Degree: PhD, Industrial Engineering, 2004, Texas A&M University

URL: http://hdl.handle.net/1969.1/1076

► This dissertation presents a methodology for the near optimal design of fixture layouts in multi-station assembly processes. An optimal fixture layout improves the robustness of… (more)

Subjects/Keywords: Fixture Layout Design; Data-mining Method; Revised Exchange Algorithm; E-optimality

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APA (6^th Edition):

Kim, P. (2004). Near optimal design of fixture layouts in multi-station assembly processes. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/1076

Chicago Manual of Style (16^th Edition):

Kim, Pansoo. “Near optimal design of fixture layouts in multi-station assembly processes.” 2004. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/1076.

MLA Handbook (7^th Edition):

Kim, Pansoo. “Near optimal design of fixture layouts in multi-station assembly processes.” 2004. Web. 11 Apr 2021.

Vancouver:

Kim P. Near optimal design of fixture layouts in multi-station assembly processes. [Internet] [Doctoral dissertation]. Texas A&M University; 2004. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/1076.

Council of Science Editors:

Kim P. Near optimal design of fixture layouts in multi-station assembly processes. [Doctoral Dissertation]. Texas A&M University; 2004. Available from: http://hdl.handle.net/1969.1/1076

15. Li, Xiugang. Optimal Design of Demand-Responsive Feeder Transit Services.

Degree: PhD, Civil Engineering, 2010, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-7074

► The general public considers Fixed-Route Transit (FRT) to be inconvenient while Demand-Responsive Transit (DRT) provides much of the desired flexibility with a door-to-door type of… (more)

▼ The general public considers Fixed-Route Transit (FRT) to be inconvenient while Demand-Responsive Transit (DRT) provides much of the desired flexibility with a door-to-door type of service. However, FRT is typically more cost efficient than DRT to deploy. Therefore, there is an increased interest in flexible transit services including all types of hybrid services that combine FRT and pure DRT. The demand-responsive feeder transit, also known as Demand-Responsive Connector (DRC), is a flexible transit service because it operates in a demand-responsive fashion within a service area and moves customers to/from a transfer point that connects to a FRT network. In this research we develop analytical models, validated by simulation, to design the DRC system. Feeder transit services are generally operated with a DRC policy which might be converted to a traditional FRT policy for higher demand. By using continuous approximations, we provide an analytical modeling framework to help planners and operators in their choice of the two policies. We compare utility functions of the two policies to derive rigorous analytical and approximate closed-form expressions of critical demand densities. They represent the switching conditions, that are functions of the parameters of each considered scenario, such as the geometry of the service area, the vehicle speed and also the weights assigned to each term contributing to the utility function: walking time, waiting time and riding time. We address the problem faced by planners in determining the optimal number of zones for dividing a service area. We develop analytical models representing the total cost functions balancing customer service quality and vehicle operating cost. We obtain close-form expressions for the FRT and approximation formulas for the DRC to determine the optimal number of zones. Finally we develop a real-case application with collected customer demand data and road network data of El Cenizo, Texas. With our analytical formulas, we obtain the optimal number of zones, and the times for switching FRT and DRC policies during a day. Simulation results considering the road network of El Cenizo demonstrate that our analytical formulas provide good estimates for practical use. Advisors/Committee Members: Quadrifoglio, Luca (advisor), Zhang, Yunlong (committee member), Curry, Guy L. (committee member), Lord, Dominique (committee member).

Subjects/Keywords: feeder transit; flexible transit; demand responsive; continuous approximation; critical demand; optimal design

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APA (6^th Edition):

Li, X. (2010). Optimal Design of Demand-Responsive Feeder Transit Services. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-7074

Chicago Manual of Style (16^th Edition):

Li, Xiugang. “Optimal Design of Demand-Responsive Feeder Transit Services.” 2010. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-7074.

MLA Handbook (7^th Edition):

Li, Xiugang. “Optimal Design of Demand-Responsive Feeder Transit Services.” 2010. Web. 11 Apr 2021.

Vancouver:

Li X. Optimal Design of Demand-Responsive Feeder Transit Services. [Internet] [Doctoral dissertation]. Texas A&M University; 2010. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-7074.

Council of Science Editors:

Li X. Optimal Design of Demand-Responsive Feeder Transit Services. [Doctoral Dissertation]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-7074

16. Zollanvari, Amin. Analytic Study of Performance of Error Estimators for Linear Discriminant Analysis with Applications in Genomics.

Degree: PhD, Electrical Engineering, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8685

► Error estimation must be used to find the accuracy of a designed classifier, an issue that is critical in biomarker discovery for disease diagnosis and… (more)

▼ Error estimation must be used to find the accuracy of a designed classifier, an issue that is critical in biomarker discovery for disease diagnosis and prognosis in genomics and proteomics. This dissertation is concerned with the analytical formulation of the joint distribution of the true error of misclassification and two of its commonly used estimators, resubstitution and leave-one-out, as well as their marginal and mixed moments, in the context of the Linear Discriminant Analysis (LDA) classification rule. In the first part of this dissertation, we obtain the joint sampling distribution of the actual and estimated errors under a general parametric Gaussian assumption. Exact results are provided in the univariate case and an accurate approximation is obtained in the multivariate case. We show how these results can be applied in the computation of conditional bounds and the regression of the actual error, given the observed error estimate. In practice the unknown parameters of the Gaussian distributions, which figure in the expressions, are not known and need to be estimated. Using the usual maximum-likelihood estimates for such parameters and plugging them into the theoretical exact expressions provides a sample-based approximation to the joint distribution, and also sample-based methods to estimate upper conditional bounds. In the second part of this dissertation, exact analytical expressions for the bias, variance, and Root Mean Square (RMS) for the resubstitution and leave-one-out error estimators in the univariate Gaussian model are derived. All probabilistic characteristics of an error estimator are given by the knowledge of its joint distribution with the true error. Partial information is contained in their mixed moments, in particular, their second mixed moment. Marginal information regarding an error estimator is contained in its marginal moments, in particular, its mean and variance. Since we are interested in estimator accuracy and wish to use the RMS to measure that accuracy, we desire knowledge of the second-order moments, marginal and mixed, with the true error. In the multivariate case, using the double asymptotic approach with the assumption of knowing the common covariance matrix of the Gaussian model, analytical expressions for the first moments, second moments, and mixed moment with the actual error for the resubstitution and leave-one-out error estimators are derived. The results provide accurate small sample approximations and this is demonstrated in the present situation via numerical comparisons. Application of the results is discussed in the context of genomics. Advisors/Committee Members: Braga-Neto, Ulisses M. (advisor), Dougherty, Edward R. (advisor), Datta, Aniruddha (committee member), Curry, Guy L. (committee member).

Subjects/Keywords: Error Estimation; Linear Discriminant Analysis; Genomics; Joint Distribution; Double Asymptotic Analysis; Cross-moments; Resubstitution; Leave-one-out

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APA (6^th Edition):

Zollanvari, A. (2012). Analytic Study of Performance of Error Estimators for Linear Discriminant Analysis with Applications in Genomics. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8685

Chicago Manual of Style (16^th Edition):

Zollanvari, Amin. “Analytic Study of Performance of Error Estimators for Linear Discriminant Analysis with Applications in Genomics.” 2012. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8685.

MLA Handbook (7^th Edition):

Zollanvari, Amin. “Analytic Study of Performance of Error Estimators for Linear Discriminant Analysis with Applications in Genomics.” 2012. Web. 11 Apr 2021.

Vancouver:

Zollanvari A. Analytic Study of Performance of Error Estimators for Linear Discriminant Analysis with Applications in Genomics. [Internet] [Doctoral dissertation]. Texas A&M University; 2012. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8685.

Council of Science Editors:

Zollanvari A. Analytic Study of Performance of Error Estimators for Linear Discriminant Analysis with Applications in Genomics. [Doctoral Dissertation]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8685

17. Jung, Seungho. Facility Siting and Layout Optimization Based on Process Safety.

Degree: PhD, Chemical Engineering, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8596

► In this work, a new approach to optimize facility layout for toxic release, fire and explosion scenarios is presented. By integrating a risk analysis in… (more)

▼ In this work, a new approach to optimize facility layout for toxic release, fire and explosion scenarios is presented. By integrating a risk analysis in the optimization formulation, safer assignments for facility layout and siting have been obtained. Accompanying with the economical concepts used in a plant layout, the new model considers the cost of willing to avoid a fatality, i.e. the potential injury cost due to accidents associated with toxic release near residential areas. For fire and explosion scenarios, the building or equipment damage cost replaces the potential injury cost. Two different approaches have been proposed to optimize the total cost related with layout. In the first phase using continuous-plane approach, the overall problem was initially modeled as a disjunctive program where the coordinates of each facility and cost-related variables are the main unknowns. Then, the convex hull approach was used to reformulate the problem as a Mixed Integer Non-Linear Program (MINLP) that identifies potential layouts by minimizing overall costs. This approach gives the coordinates of each facility in a continuous plane, and estimates for the total length of pipes, the land area, and the selection of safety devices. Finally, the 3D-computational fluid dynamics (CFD) was used to compare the difference between the initial layout and the final layout in order to see how obstacles and separation distances affect the dispersion or overpressures of affected facilities. One of the CFD programs, ANSYS CFX was employed for the dispersion study and Flame Acceleration Simulator (FLACS) for the fires and explosions. In the second phase for fire and explosion scenarios, the study is focused on finding an optimal placement for hazardous facilities and other process plant buildings using the optimization theory and mapping risks on the given land in order to calculate risk in financial terms. The given land is divided in a square grid of which the sides have a certain size and in which each square acquires a risk-score. These risk-scores such as the probability of structural damage are to be multiplied by prices of potential facilities which would be built on the grid. Finally this will give us the financial risk. Accompanying the suggested safety concepts, the new model takes into account construction and operational costs. The overall cost of locations is a function of piping cost, management cost, protection device cost, and financial risk. This approach gives the coordinates of the best location of each facility in a 2-D plane, and estimates the total piping length. Once the final layout is obtained, the CFD code, FLACS is used to simulate and consider obstacle effects in 3-D space. The outcome of this study will be useful in assisting the selection of location for process plant buildings and risk management. Advisors/Committee Members: Mannan, M. Sam (advisor), Laird, Carl D. (committee member), El-Halwagi, Mahmoud (committee member), Curry, Guy L. (committee member).

Subjects/Keywords: Facility siting; layout; optimization; toxic gas release; flammable gas release; PHAST; FLACS; CFX; QRA

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APA (6^th Edition):

Jung, S. (2012). Facility Siting and Layout Optimization Based on Process Safety. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8596

Chicago Manual of Style (16^th Edition):

Jung, Seungho. “Facility Siting and Layout Optimization Based on Process Safety.” 2012. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8596.

MLA Handbook (7^th Edition):

Jung, Seungho. “Facility Siting and Layout Optimization Based on Process Safety.” 2012. Web. 11 Apr 2021.

Vancouver:

Jung S. Facility Siting and Layout Optimization Based on Process Safety. [Internet] [Doctoral dissertation]. Texas A&M University; 2012. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8596.

Council of Science Editors:

Jung S. Facility Siting and Layout Optimization Based on Process Safety. [Doctoral Dissertation]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8596

18. Torres Soto, Joaquin. Dynamic and Robust Capacitated Facility Location in Time Varying Demand Environments.

Degree: PhD, Industrial Engineering, 2010, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-620

► This dissertation studies models for locating facilities in time varying demand environments. We describe the characteristics of the time varying demand that motivate the analysis… (more)

▼ This dissertation studies models for locating facilities in time varying demand environments. We describe the characteristics of the time varying demand that motivate the analysis of our location models in terms of total demand and the change in value and location of the demand of each customer. The first part of the dissertation is devoted to the dynamic location model, which determines the optimal time and location for establishing capacitated facilities when demand and cost parameters are time varying. This model minimizes the total cost over a discrete and finite time horizon for establishing, operating, and closing facilities, including the transportation costs for shipping demand from facilities to customers. The model is solved using Lagrangian relaxation and Benders? decomposition. Computational results from different time varying total demand structures demonstrate, empirically, the performance of these solution methods. The second part of the dissertation studies two location models where relocation of facilities is not allowed and the objective is to determine the optimal location of capacitated facilities that will have a good performance when demand and cost parameters are time varying. The first model minimizes the total cost for opening and operating facilities and the associated transportation costs when demand and cost parameters are time varying. The model is solved using Benders? decomposition. We show that in the presence of high relocation costs of facilities (opening and closing costs), this model can be solved as a special case by the dynamic location model. The second model minimizes the maximum regret or opportunity loss between a robust configuration of facilities and the optimal configuration for each time period. We implement local search and simulated annealing metaheuristics to efficiently obtain near optimal solutions for this model. Advisors/Committee Members: Uster, Halit (advisor), Curry, Guy L. (committee member), Tekin, Eylem (committee member), Flores, Benito E. (committee member).

Subjects/Keywords: Facility; Location; Capacitated facility location; Dynamic facility location; Facility location; Location theory; Logistics; Lagrangian relaxation; Benders decomposition; Robust; Robust facility location; Robustness; Minimax regret; Heuristics; Local search; Simulated annealing

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APA (6^th Edition):

Torres Soto, J. (2010). Dynamic and Robust Capacitated Facility Location in Time Varying Demand Environments. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-620

Chicago Manual of Style (16^th Edition):

Torres Soto, Joaquin. “Dynamic and Robust Capacitated Facility Location in Time Varying Demand Environments.” 2010. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-620.

MLA Handbook (7^th Edition):

Torres Soto, Joaquin. “Dynamic and Robust Capacitated Facility Location in Time Varying Demand Environments.” 2010. Web. 11 Apr 2021.

Vancouver:

Torres Soto J. Dynamic and Robust Capacitated Facility Location in Time Varying Demand Environments. [Internet] [Doctoral dissertation]. Texas A&M University; 2010. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-620.

Council of Science Editors:

Torres Soto J. Dynamic and Robust Capacitated Facility Location in Time Varying Demand Environments. [Doctoral Dissertation]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-620

19. Kim, Seong D. Tradeoff between Investments in Infrastructure and Forecasting when Facing Natural Disaster Risk.

Degree: PhD, Industrial Engineering, 2010, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-749

► Hurricane Katrina of 2005 was responsible for at least 81 billion dollars of property damage. In planning for such emergencies, society must decide whether to… (more)

Subjects/Keywords: infrastructure; forecast quality; natural disaster; hurricane; evacuation speed; forecast accuracy; hazard risk; emergency

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APA (6^th Edition):

Kim, S. D. (2010). Tradeoff between Investments in Infrastructure and Forecasting when Facing Natural Disaster Risk. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-749

Chicago Manual of Style (16^th Edition):

Kim, Seong D. “Tradeoff between Investments in Infrastructure and Forecasting when Facing Natural Disaster Risk.” 2010. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-749.

MLA Handbook (7^th Edition):

Kim, Seong D. “Tradeoff between Investments in Infrastructure and Forecasting when Facing Natural Disaster Risk.” 2010. Web. 11 Apr 2021.

Vancouver:

Kim SD. Tradeoff between Investments in Infrastructure and Forecasting when Facing Natural Disaster Risk. [Internet] [Doctoral dissertation]. Texas A&M University; 2010. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-749.

Council of Science Editors:

Kim SD. Tradeoff between Investments in Infrastructure and Forecasting when Facing Natural Disaster Risk. [Doctoral Dissertation]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-749

20. Mutlu, Fatih. The transporter's impact on channel coordination and contractual agreements.

Degree: PhD, Industrial Engineering, 2006, Texas A&M University

URL: http://hdl.handle.net/1969.1/4227

► This dissertation focuses on the recent supply chain initiatives, such as Vendor Managed Inventory (VMI) and Third-Party Logistics (3PL), enabling the coordination of supply chain… (more)

Subjects/Keywords: channel coordination; inventory; transportation; pricing; shipment consolidation

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APA (6^th Edition):

Mutlu, F. (2006). The transporter's impact on channel coordination and contractual agreements. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/4227

Chicago Manual of Style (16^th Edition):

Mutlu, Fatih. “The transporter's impact on channel coordination and contractual agreements.” 2006. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/4227.

MLA Handbook (7^th Edition):

Mutlu, Fatih. “The transporter's impact on channel coordination and contractual agreements.” 2006. Web. 11 Apr 2021.

Vancouver:

Mutlu F. The transporter's impact on channel coordination and contractual agreements. [Internet] [Doctoral dissertation]. Texas A&M University; 2006. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/4227.

Council of Science Editors:

Mutlu F. The transporter's impact on channel coordination and contractual agreements. [Doctoral Dissertation]. Texas A&M University; 2006. Available from: http://hdl.handle.net/1969.1/4227

21. Burgos Fuentes, Sergio Armando. Evaluation and redesign of a company's distribution network.

Degree: Doctor of Engineering, Engineering, 2004, Texas A&M University

URL: http://hdl.handle.net/1969.1/1062

► The current Record of Study presents the qualitative and quantitative analysis of a company's network of distribution centers with the purpose of determining the convenience… (more)

Subjects/Keywords: Distribution Logistics; Operations Research

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APA (6^th Edition):

Burgos Fuentes, S. A. (2004). Evaluation and redesign of a company's distribution network. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/1062

Chicago Manual of Style (16^th Edition):

Burgos Fuentes, Sergio Armando. “Evaluation and redesign of a company's distribution network.” 2004. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/1062.

MLA Handbook (7^th Edition):

Burgos Fuentes, Sergio Armando. “Evaluation and redesign of a company's distribution network.” 2004. Web. 11 Apr 2021.

Vancouver:

Burgos Fuentes SA. Evaluation and redesign of a company's distribution network. [Internet] [Doctoral dissertation]. Texas A&M University; 2004. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/1062.

Council of Science Editors:

Burgos Fuentes SA. Evaluation and redesign of a company's distribution network. [Doctoral Dissertation]. Texas A&M University; 2004. Available from: http://hdl.handle.net/1969.1/1062

Texas A&M University

22. Pham, Viet. A global optimization approach to pooling problems in refineries.

Degree: MS, Chemical Engineering, 2009, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-1445

► The pooling problem is an important optimization problem that is encountered in operation and scheduling of important industrial processes within petroleum refineries. The key objective… (more)

▼ The pooling problem is an important optimization problem that is encountered in operation and scheduling of important industrial processes within petroleum refineries. The key objective of pooling is to mix various intermediate products to achieve desired properties and quantities of products. First, intermediate streams from various processing units are mixed and stored in intermediate tanks referred to as pools. The stored streams in pools are subsequently allowed to mix to meet varying market demands. While these pools enhance the operational flexibility of the process, they complicate the decisionmaking process needed for optimization. The problem to find the least costly mixing recipe from intermediate streams to pools and then from pools to sale products is referred to as the pooling problem. The research objective is to contribute an approach to solve this problem. The pooling problem can be formulated as an optimization program whose objective is to minimize cost or maximize profit while determining the optimal allocation of intermediate streams to pools and the blending of pools to final products. Because of the presence of bilinear terms, the resulting formulation is nonconvex which makes it very difficult to attain the global solution. Consequently, there is a need to develop computationally-efficient and easy-to-implement global-optimization techniques to solve the pooling problem. In this work, a new approach is introduced for the global optimization of pooling problems. The approach is based on three concepts: linearization by discretizing nonlinear variables, pre-processing using implicit enumeration of the discretization to form a convex-hull which limits the size of the search space, and application of integer cuts to ensure compatibility between the original problem and the discretized formulation. The continuous quality variables contributing to bilinear terms are first discretized. The discretized problem is a mixed integer linear program (MILP) and can be globally solved in a computationally effective manner using branch and bound method. The merits of the proposed approach are illustrated by solving test case studies from literature and comparison with published results. Advisors/Committee Members: El-Halwagi, Mahmoud M. (advisor), Curry, Guy L. (committee member), Hahn, Juergen (committee member).

Subjects/Keywords: global optimization; Pooling problem; refinery; discretization; LINGO; convex hull

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APA (6^th Edition):

Pham, V. (2009). A global optimization approach to pooling problems in refineries. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-1445

Chicago Manual of Style (16^th Edition):

Pham, Viet. “A global optimization approach to pooling problems in refineries.” 2009. Masters Thesis, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-1445.

MLA Handbook (7^th Edition):

Pham, Viet. “A global optimization approach to pooling problems in refineries.” 2009. Web. 11 Apr 2021.

Vancouver:

Pham V. A global optimization approach to pooling problems in refineries. [Internet] [Masters thesis]. Texas A&M University; 2009. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1445.

Council of Science Editors:

Pham V. A global optimization approach to pooling problems in refineries. [Masters Thesis]. Texas A&M University; 2009. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1445

Texas A&M University

23. Lopez Hernandez, Henry De Jesus. Optimal fracture treatment design for dry gas wells maximizes well performance in the presence of non-Darcy flow effects.

Degree: MS, Petroleum Engineering, 2004, Texas A&M University

URL: http://hdl.handle.net/1969.1/1103

► This thesis presents a methodology based on Proppant Number approach for optimal fracture treatment design of natural gas wells considering non-Darcy flow effects in the… (more)

Subjects/Keywords: hydraulic fracturing; design; non-Darcy flow; optimization

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APA (6^th Edition):

Lopez Hernandez, H. D. J. (2004). Optimal fracture treatment design for dry gas wells maximizes well performance in the presence of non-Darcy flow effects. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/1103

Chicago Manual of Style (16^th Edition):

Lopez Hernandez, Henry De Jesus. “Optimal fracture treatment design for dry gas wells maximizes well performance in the presence of non-Darcy flow effects.” 2004. Masters Thesis, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/1103.

MLA Handbook (7^th Edition):

Lopez Hernandez, Henry De Jesus. “Optimal fracture treatment design for dry gas wells maximizes well performance in the presence of non-Darcy flow effects.” 2004. Web. 11 Apr 2021.

Vancouver:

Lopez Hernandez HDJ. Optimal fracture treatment design for dry gas wells maximizes well performance in the presence of non-Darcy flow effects. [Internet] [Masters thesis]. Texas A&M University; 2004. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/1103.

Council of Science Editors:

Lopez Hernandez HDJ. Optimal fracture treatment design for dry gas wells maximizes well performance in the presence of non-Darcy flow effects. [Masters Thesis]. Texas A&M University; 2004. Available from: http://hdl.handle.net/1969.1/1103

Texas A&M University

24. Easwaran, Gopalakrishnan. Design and development of a vehicle routing system under capacity, time-windows and rush-order reloading considerations.

Degree: MS, Industrial Engineering, 2004, Texas A&M University

URL: http://hdl.handle.net/1969.1/1143

► The purpose of this research is to present the design and development of a routing system, custom developed for a fence manufacturing company in the… (more)

▼ The purpose of this research is to present the design and development of a routing system, custom developed for a fence manufacturing company in the continental US. The objective of the routing module of the system is to generate least cost routes from the home-center of the company to a set of delivery locations. Routes are evolved for a set of customer locations based on the sales order information and are frequently modified to include rush orders. These routes are such that each delivery is made within a given time window. Further, total truckload of all delivery locations over any particular route is not allowed to exceed the weight and volume capacities of the truck. The basic system modules such as user interface functions and database are designed using MS Access 2000. An interface module to retrieve data from existing ERP system of the company is developed to import pick-ticket information. A customer inter-distance maintenance module is designed with the abilities of a learning tool to reduce information retrieval time between the routing system and the GIS server. The Graphical User Interface with various screen forms and printable reports is developed along with the routing module to achieve complete system functionality and to provide an efficient logistics solution. This problem, formulated as a mixed-integer program, is of particular interest due to its generality to model problem scenarios in the production shop such as job-shop scheduling, material handling, etc. This problem is coded and solved for instances with different input parameters using AMPL/CPLEX. Results of test runs for the company data show that the solution time increases exponentially with the number of customers. Hence, a heuristic approach is developed and implemented. Sample runs with small instances are solved for optimality using AMPL/CPLEX and are used to compare the performance of the heuristics. However, test runs solved using the heuristics for larger instances are compared with the manual routing costs. The comparison shows a considerable cost savings for heuristic solutions. Further, a what-if analysis module is implemented to aid the dispatcher in choosing input parameters based on sensitivity analysis. In conclusion, further improvement of the routing system and future research directions are proposed. Advisors/Committee Members: Cetinkaya, Sila (advisor), Lawrence, F. Barry (committee member), Curry, Guy L. (committee member).

Subjects/Keywords: Vehicle Routing; Heuristics; Rush-order processing.

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APA (6^th Edition):

Easwaran, G. (2004). Design and development of a vehicle routing system under capacity, time-windows and rush-order reloading considerations. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/1143

Chicago Manual of Style (16^th Edition):

Easwaran, Gopalakrishnan. “Design and development of a vehicle routing system under capacity, time-windows and rush-order reloading considerations.” 2004. Masters Thesis, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/1143.

MLA Handbook (7^th Edition):

Easwaran, Gopalakrishnan. “Design and development of a vehicle routing system under capacity, time-windows and rush-order reloading considerations.” 2004. Web. 11 Apr 2021.

Vancouver:

Easwaran G. Design and development of a vehicle routing system under capacity, time-windows and rush-order reloading considerations. [Internet] [Masters thesis]. Texas A&M University; 2004. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/1143.

Council of Science Editors:

Easwaran G. Design and development of a vehicle routing system under capacity, time-windows and rush-order reloading considerations. [Masters Thesis]. Texas A&M University; 2004. Available from: http://hdl.handle.net/1969.1/1143

Texas A&M University

25. Agarwal, Pranab. Conceptual design of long-span trusses using multi-stage heuristics.

Degree: MS, Civil Engineering, 2006, Texas A&M University

URL: http://hdl.handle.net/1969.1/3863

► A hybrid method that addresses the design and optimization of long-span steel trusses is presented. By utilizing advancements in present day computing and biologically inspired… (more)

▼ A hybrid method that addresses the design and optimization of long-span steel trusses is presented. By utilizing advancements in present day computing and biologically inspired analysis and design, an effort has been made to automate the process of evolving optimal trusses in an unstructured problem domain. Topology, geometry and sizing optimization of trusses are simultaneously addressed using a three stage methodology. Multi-objective genetic algorithms are used to optimize the member section sizes of truss topologies and geometries. Converting constraints into additional objectives provides a robust algorithm that results in improved convergence to the pareto-optimal set of solutions. In addition, the pareto-curve plotted based on how well the different objectives are satisfied helps in identifying the trade-offs that exist between these objectives, while also providing an efficient way to rank the population of solutions during the search process. A comparison study between multi-objective genetic algorithms, simulated annealing, and reactive taboo search is conducted to evaluate the efficiency of each method with relation to its overall performance, computational expense, sensitivity to initial parameter settings, and repeatability of finding near-global optimal designs. The benefit of using a three stage approach, and also implementing the entire model on parallel computers, is the high level of computational efficiency that is obtained for the entire process and the near-optimal solutions obtained. The overall efficiency and effectiveness of this method has been established by comparing the truss design results obtained using this method on bridge and roof truss benchmark problems with truss designs obtained by other researchers. One of the salient features of thisresearch is the large number of optimal trusses that are produced as the final result. The range of designs available provides the user with the flexibility to select the truss design that best matches their design requirements. By supporting human-computer interactions between these stages, the program also incorporates subjective aesthetic criteria, which assist in producing final designs in consonance with the user's requirements. Advisors/Committee Members: Raich, Anne M. (advisor), Curry, Guy L. (committee member), Hueste, Mary Beth D. (committee member).

Subjects/Keywords: structural engineering; design and analysis; roof and bridge trusses; multi-objective genetic algorithms; heuristics; simulated annealing; reactive taboo search; unstructured problem domain; conceptual design

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APA (6^th Edition):

Agarwal, P. (2006). Conceptual design of long-span trusses using multi-stage heuristics. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/3863

Chicago Manual of Style (16^th Edition):

Agarwal, Pranab. “Conceptual design of long-span trusses using multi-stage heuristics.” 2006. Masters Thesis, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/3863.

MLA Handbook (7^th Edition):

Agarwal, Pranab. “Conceptual design of long-span trusses using multi-stage heuristics.” 2006. Web. 11 Apr 2021.

Vancouver:

Agarwal P. Conceptual design of long-span trusses using multi-stage heuristics. [Internet] [Masters thesis]. Texas A&M University; 2006. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/3863.

Council of Science Editors:

Agarwal P. Conceptual design of long-span trusses using multi-stage heuristics. [Masters Thesis]. Texas A&M University; 2006. Available from: http://hdl.handle.net/1969.1/3863

Texas A&M University

26. Sellamuthu, Sivakumar. An Effective Implementation of Operational Inventory Management.

Degree: Doctor of Engineering, Engineering, 2010, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-786

► This Record of Study describes the Doctor of Engineering (DE) internship experience at the Supply Chain Systems Laboratory (SCSL) at Texas A&M University. The objective… (more)

Subjects/Keywords: Inventory Management; Data Analysis Automation; Engineering Management; Project Management; Supply Chain Management; Information Technology; Data Integrity; Data Quality; Inventory Stratification; Forecasting; Replenishment

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APA (6^th Edition):

Sellamuthu, S. (2010). An Effective Implementation of Operational Inventory Management. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-786

Chicago Manual of Style (16^th Edition):

Sellamuthu, Sivakumar. “An Effective Implementation of Operational Inventory Management.” 2010. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-786.

MLA Handbook (7^th Edition):

Sellamuthu, Sivakumar. “An Effective Implementation of Operational Inventory Management.” 2010. Web. 11 Apr 2021.

Vancouver:

Sellamuthu S. An Effective Implementation of Operational Inventory Management. [Internet] [Doctoral dissertation]. Texas A&M University; 2010. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-786.

Council of Science Editors:

Sellamuthu S. An Effective Implementation of Operational Inventory Management. [Doctoral Dissertation]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-786

Texas A&M University

27. Sun, Feng. Stochastic analyses arising from a new approach for closed queueing networks.

Degree: PhD, Industrial Engineering, 2009, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-1016

► Analyses are addressed for a number of problems in queueing systems and stochastic modeling that arose due to an investigation into techniques that could be… (more)

▼ Analyses are addressed for a number of problems in queueing systems and stochastic modeling that arose due to an investigation into techniques that could be used to approximate general closed networks. In Chapter II, a method is presented to calculate the system size distribution at an arbitrary point in time and at departures for a (n)/G/1/N queue. The analysis is carried out using an embedded Markov chain approach. An algorithm is also developed that combines our analysis with the recursive method of Gupta and Rao. This algorithm compares favorably with that of Gupta and Rao and will solve some situations when Gupta and Rao's method fails or becomes intractable. In Chapter III, an approach is developed for generating exact solutions of the time-dependent conditional joint probability distributions for a phase-type renewal process. Closed-form expressions are derived when a class of Coxian distributions are used for the inter-renewal distribution. The class of Coxian distributions was chosen so that solutions could be obtained for any mean and variance desired in the inter-renewal times. In Chapter IV, an algorithm is developed to generate numerical solutions for the steady-state system size probabilities and waiting time distribution functions of the SM/PH/1/N queue by using the matrix-analytic method. Closed form results are also obtained for particular situations of the preceding queue. In addition, it is demonstrated that the SM/PH/1/N model can be implemented to the analysis of a sequential two-queue system. This is an extension to the work by Neuts and Chakravarthy. In Chapter V, principal results developed in the preceding chapters are employed for approximate analysis of the closed network of queues with arbitrary service times. Specifically, the (n)/G/1/N queue is applied to closed networks of a general topology, and a sequential two-queue model consisting of the (n)/G/1/N and SM/PH/1/N queues is proposed for tandem queueing networks. Advisors/Committee Members: Feldman, Richard M. (advisor), Curry, Guy L. (committee member), Larson, David R. (committee member), Peters, Brett A. (committee member).

Subjects/Keywords: Queueing; Stochastic processes; Applied probability; Phase-type distributions; Closed queueing networks

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APA (6^th Edition):

Sun, F. (2009). Stochastic analyses arising from a new approach for closed queueing networks. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-1016

Chicago Manual of Style (16^th Edition):

Sun, Feng. “Stochastic analyses arising from a new approach for closed queueing networks.” 2009. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-1016.

MLA Handbook (7^th Edition):

Sun, Feng. “Stochastic analyses arising from a new approach for closed queueing networks.” 2009. Web. 11 Apr 2021.

Vancouver:

Sun F. Stochastic analyses arising from a new approach for closed queueing networks. [Internet] [Doctoral dissertation]. Texas A&M University; 2009. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1016.

Council of Science Editors:

Sun F. Stochastic analyses arising from a new approach for closed queueing networks. [Doctoral Dissertation]. Texas A&M University; 2009. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1016

Texas A&M University

28. Rabie, Ahmed Ibrahim El Said. Nonlinear estimation of water network demands form limited measurement information.

Degree: MS, Chemical Engineering, 2009, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-3132

► Access to clean drinking water is very important to the health and well-being of the population. Mathematical modeling, optimization, and online estimation are needed to… (more)

Subjects/Keywords: Nonlinear Optimization; Water Networks; Water Demands; Estimation Formulation

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APA (6^th Edition):

Rabie, A. I. E. S. (2009). Nonlinear estimation of water network demands form limited measurement information. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-3132

Chicago Manual of Style (16^th Edition):

Rabie, Ahmed Ibrahim El Said. “Nonlinear estimation of water network demands form limited measurement information.” 2009. Masters Thesis, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-3132.

MLA Handbook (7^th Edition):

Rabie, Ahmed Ibrahim El Said. “Nonlinear estimation of water network demands form limited measurement information.” 2009. Web. 11 Apr 2021.

Vancouver:

Rabie AIES. Nonlinear estimation of water network demands form limited measurement information. [Internet] [Masters thesis]. Texas A&M University; 2009. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-3132.

Council of Science Editors:

Rabie AIES. Nonlinear estimation of water network demands form limited measurement information. [Masters Thesis]. Texas A&M University; 2009. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-3132

Texas A&M University

29. Chae, Junjae. Concurrent design of facility layout and flow-based department formation.

Degree: PhD, Industrial Engineering, 2005, Texas A&M University

URL: http://hdl.handle.net/1969.1/1606

► The design of facility layout takes into account a number of issues including the formation of departments, the layout of these, the determination of the… (more)

Subjects/Keywords: Facility Layout; Department Formation; Material Handling; Multi-bay Facility; Genetic Algorithms; Memetic Algorithms

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APA (6^th Edition):

Chae, J. (2005). Concurrent design of facility layout and flow-based department formation. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/1606

Chicago Manual of Style (16^th Edition):

Chae, Junjae. “Concurrent design of facility layout and flow-based department formation.” 2005. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/1606.

MLA Handbook (7^th Edition):

Chae, Junjae. “Concurrent design of facility layout and flow-based department formation.” 2005. Web. 11 Apr 2021.

Vancouver:

Chae J. Concurrent design of facility layout and flow-based department formation. [Internet] [Doctoral dissertation]. Texas A&M University; 2005. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/1606.

Council of Science Editors:

Chae J. Concurrent design of facility layout and flow-based department formation. [Doctoral Dissertation]. Texas A&M University; 2005. Available from: http://hdl.handle.net/1969.1/1606

Texas A&M University

30. Kim, Man-Keun. Economic investigation of discount factors for agricultural greenhouse gas emission offsets.

Degree: PhD, Agricultural Economics, 2005, Texas A&M University

URL: http://hdl.handle.net/1969.1/2187

► This dissertation analyzes the basis for and magnitudes of discount factors based on the characteristics of greenhouse gas emission (GHGE) offsets that are applied to… (more)

▼ This dissertation analyzes the basis for and magnitudes of discount factors based on the characteristics of greenhouse gas emission (GHGE) offsets that are applied to the GHGE reduction projects, concentrating on agricultural projects. Theoretical approaches to discount factors, estimation and incorporation of discount factors procedures are developed. Discount factors would be imposed by credit purchasers due to noncompliance with regulatory program of the credits with GHG program including consideration of shortfall penalties and limited durations. Discount factors are proposed for (i) additionality, (ii) leakage, (iii) permanence, and (iv) uncertainty. Additionality arise when the region where an AO project is being proposed would have substantial adoption of the AO practice in the absence of GHG programs (business as usual GHGE offset). Leakage arises when the effect of a program is offset by an induced increase in economic activity and accompanying emissions elsewhere. The leakage effect depends on demand and supply elasticities. Permanence reflects the saturation and volatility characteristics of carbon sequestration. Carbon is stored in a volatile form and can be released quickly to the atmosphere when an AO practice is discontinued. The permanence discount depends on the project design including practice continuation after the program and the dynamic rate of offset. Also, consideration of multiple offsets is important. Uncertainty arises due to the stochastic nature of project quantity. The uncertainty discount tends to be smaller the larger the size of the offset contract due to aggregation over space and time. The magnitude of these discounts is investigated in Southeast Texas rice discontinuation study. The additionality and the leakage discounts are found to play an important role in case of rice lands conversion to other crops but less so for pasture conversions and yet less for forest conversions. The permanence discount is important when converting to other crops and short rotation forestry. When all discounts are considered, rice lands conversion to forest yields claimable credits amounting to 52.8% ~ 77.5% of the total offset. When converting rice lands to pasture, the claimable credits 45.1% ~ 64.2%, while a conversion of rice lands to other crops yields claimable credits 38.9% ~ 40.4%. Advisors/Committee Members: McCarl, Bruce A. (advisor), Curry, Guy L. (committee member), Mitchell, Paul D. (committee member), Woodward, Richard T. (committee member).

Subjects/Keywords: Climate Change; Carbon Sequestration; Additionality; Permanence; Leakage; Uncertainty; Offset Credits

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APA (6^th Edition):

Kim, M. (2005). Economic investigation of discount factors for agricultural greenhouse gas emission offsets. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/2187

Chicago Manual of Style (16^th Edition):

Kim, Man-Keun. “Economic investigation of discount factors for agricultural greenhouse gas emission offsets.” 2005. Doctoral Dissertation, Texas A&M University. Accessed April 11, 2021. http://hdl.handle.net/1969.1/2187.

MLA Handbook (7^th Edition):

Kim, Man-Keun. “Economic investigation of discount factors for agricultural greenhouse gas emission offsets.” 2005. Web. 11 Apr 2021.

Vancouver:

Kim M. Economic investigation of discount factors for agricultural greenhouse gas emission offsets. [Internet] [Doctoral dissertation]. Texas A&M University; 2005. [cited 2021 Apr 11]. Available from: http://hdl.handle.net/1969.1/2187.

Council of Science Editors:

Kim M. Economic investigation of discount factors for agricultural greenhouse gas emission offsets. [Doctoral Dissertation]. Texas A&M University; 2005. Available from: http://hdl.handle.net/1969.1/2187

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