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Optimization Of Biomass Logistics System Using Genetic Algorithm And Particle Swarm Optimization For Biofuel Production, Ethel Regina Martinez-Schabez 2013 University of Texas at El Paso

Optimization Of Biomass Logistics System Using Genetic Algorithm And Particle Swarm Optimization For Biofuel Production, Ethel Regina Martinez-Schabez

Open Access Theses & Dissertations

As time goes by, Renewable Energy keeps proving to be an important and potential replacement for fossil fuels. All the different types of Renewable Energy offer a relief to the environmental aftermaths of the prolonged reliance on fossil fuel energy. Bioenergy is one of the types of Renewable Energy that can help by minimizing the emissions of fossil fuels. The Energy Independence and Security Act mandates the use of 21 billion gallons of advanced biofuels including 16 billion gallons of cellulosic biofuels by the year 2022. Biomass and Biofuels can clearly become a significant aid to sustainably supply energy in …


Experiments To Measure The Effects Of Timber Harvesting Equipment On Surface Lithic Scatters, Douglas J. Baughman 2013 Central Washington University

Experiments To Measure The Effects Of Timber Harvesting Equipment On Surface Lithic Scatters, Douglas J. Baughman

All Master's Theses

The importance of cultural resource preservation cannot be overstated; however local economies are at least as important. Due to conservative archaeological site protection practices in Region 5 of the United States Forest Service, the economy of Northeastern California is being adversely affected. In an attempt to help the Forest Service make more informed management decisions and improve the Northeastern California economy, I undertook experiments on the effects of timber harvesting on lithic scatters on Modoc National Forest. The experiments involved placement of 225 glass tiles (proxy lithics) in each of three plots subject to vehicle traffic and log dragging by …


Nylon Tension Pid Control During Raw Tire Assembly, Yuan-yu Luo 2013 Georgia Southern University

Nylon Tension Pid Control During Raw Tire Assembly, Yuan-Yu Luo

College of Graduate Studies: Theses & Dissertations

The purpose of this study is to evaluate several control methods to see which one has the best control of nylon tension during raw tire assembly. After nylon application step of the tire building process, the shape of the tire will undergo inflation that causes the nylon layers to expand and produces tension gradient. To overcome such a problem, the process needs to preapply a nylon trip with a gradient of tension so the tension can be balanced after the inflation step. The study evaluated several PID controllers and gathered data to see which controller results in the best nylon …


Supply Chain Optimization Of Blood Products, Serkan Gunpinar 2013 University of South Florida

Supply Chain Optimization Of Blood Products, Serkan Gunpinar

USF Tampa Graduate Theses and Dissertations

Major challenges in the management of blood supply chain are related to the shortage and wastage of the blood products. Given the perishability characteristics of blood which can be stored up to a limited number of days, if hospitals and blood centers keep an excessive number of blood units on inventory, wastages may occur. On the other hand, if sufficient number of blood units are not stored on inventory, shortages of this resource may cause the cancellations of important activities and increase the fatality rates at hospitals. Three mathematical models have been developed with the goal to improve the efficiency …


On The Maintenance Modeling And Optimization Of Repairable Systems: Two Different Scenarios, Suzan Alaswad 2012 University of Arkansas, Fayetteville

On The Maintenance Modeling And Optimization Of Repairable Systems: Two Different Scenarios, Suzan Alaswad

Graduate Theses and Dissertations

The use of mathematical modeling for the purpose of analyzing and optimizing the performance of repairable systems is widely studied in the literature. In this dissertation, we study two different scenarios on the maintenance modeling and optimization of repairable systems. First, we study the long-run availability of a traditional repairable system that is subjected to imperfect corrective maintenance. We use Kijima's second virtual age model to describe the imperfect repair process. Because of the complexity of the underlying probability models, we use simulation modeling to estimate availability performance and meta-modeling to convert the reliability and maintainability parameters of the repairable …


Capacity Planning For Elderly Care In Ireland Using Simulation Modeling, Mohamed Ragab, Waleed Abo Hamad, Amr Arisha 2012 Technological University Dublin

Capacity Planning For Elderly Care In Ireland Using Simulation Modeling, Mohamed Ragab, Waleed Abo Hamad, Amr Arisha

Conference papers

Global population aging is creating an immense pressure on healthcare facilities making them unable to cope with the growing demand for elderly healthcare services. Current demand-supply gaps result in prolonged waiting times for patients and substantial cost burdens for healthcare systems due to delayed discharges. This paper describes a project aimed at presenting modeling and simulation to address elderly care pathways within the Irish healthcare sector. The management of frail patients admitted to acute hospitals and the introduction of the new intermediate care beds are alternative interventions that healthcare executives are interested in simulating to examine their impact on the …


The Factors Behind A Successful Implementation Of Electronic Health Records Systems, Anjee Gorkhali 2012 Old Dominion University

The Factors Behind A Successful Implementation Of Electronic Health Records Systems, Anjee Gorkhali

Engineering Management & Systems Engineering Theses & Dissertations

This research explores the role that budget for Information System (IS) and technical expertise of healthcare service provider staff play on the successful leap from a partial to exhaustive implementation of Electronic Health Records (EHR) Systems. Technical expertise in Information Systems might not be easily measurable directly, but there are a number of indicators that could be used as a proxy, such as: Information System (IS) Department Budget, number of IS staff and the extent of technical trainings provided by the IS department to the clinical staff. This research study hypothesizes that quality technical trainings conducted by an IS department …


Minimization Of Collateral Damage In Airdrops And Airstrikes, Steven P. Dillenburger 2012 Air Force Institute of Technology

Minimization Of Collateral Damage In Airdrops And Airstrikes, Steven P. Dillenburger

Theses and Dissertations

Collateral damage presents a significant risk during air drops and airstrikes, risking citizens' lives and property, straining the relationship between the United States Air Force and host nations. This dissertation presents a methodology to determine the optimal location for making supply airdrops in order to minimize collateral damage while maintaining a high likelihood of successful recovery. A series of non-linear optimization algorithms is presented along with their relative success in finding the optimal location in the airdrop problem. Additionally, we present a quick algorithm for accurately creating the Pareto frontier in the multi-objective airstrike problem. We demonstrate the effect of …


The Multiobjective Average Network Flow Problem: Formulations, Algorithms, Heuristics, And Complexity, Jeremy D. Jordan 2012 Air Force Institute of Technology

The Multiobjective Average Network Flow Problem: Formulations, Algorithms, Heuristics, And Complexity, Jeremy D. Jordan

Theses and Dissertations

Integrating value focused thinking with the shortest path problem results in a unique formulation called the multiobjective average shortest path problem. We prove this is NP-complete for general graphs. For directed acyclic graphs, an efficient algorithm and even faster heuristic are proposed. While the worst case error of the heuristic is proven unbounded, its average performance on random graphs is within 3% of the optimal solution. Additionally, a special case of the more general biobjective average shortest path problem is given, allowing tradeoffs between decreases in arc set cardinality and increases in multiobjective value; the algorithm to solve the average …


The In-Transit Vigilant Covering Tour Problem Of Routing Unmanned Ground Vehicles, Huang Teng Tan 2012 Air Force Institute of Technology

The In-Transit Vigilant Covering Tour Problem Of Routing Unmanned Ground Vehicles, Huang Teng Tan

Theses and Dissertations

The routing of unmanned ground vehicles for the surveillance and protection of key installations is modeled as a new variant of the Covering Tour Problem (CTP). The CTP structure provides both the routing and target sensing components of the installation protection problem. Our variant is called the in-transit Vigilant Covering Tour Problem (VCTP) and considers not only the vertex cover but also the additional edge coverage capability of the unmanned ground vehicle while sensing in-transit between vertices. The VCTP is formulated as a Traveling Salesman Problem (TSP) with a dual set covering structure involving vertices and edges. An empirical study …


Study On Optimal Dwell Time At Jakarta International Container Terminal, Siti Nurrochmah Badrudin 2012 World Maritime University

Study On Optimal Dwell Time At Jakarta International Container Terminal, Siti Nurrochmah Badrudin

World Maritime University Dissertations

No abstract provided.


Freight Forecasting Of Dry Bulk Market Based On The Bp Neural Network, Qianran Huang 2012 World Maritime University

Freight Forecasting Of Dry Bulk Market Based On The Bp Neural Network, Qianran Huang

World Maritime University Dissertations

No abstract provided.


Container-Handling Operation Optimization At Koja Container Terminal, Moh Taufik Hidayat 2012 World Maritime University

Container-Handling Operation Optimization At Koja Container Terminal, Moh Taufik Hidayat

World Maritime University Dissertations

No abstract provided.


Design And Implementation Of Erp Software In Material Supply Chain Management For Siix Corp., Xing'er Chen 2012 World Maritime University

Design And Implementation Of Erp Software In Material Supply Chain Management For Siix Corp., Xing'er Chen

World Maritime University Dissertations

No abstract provided.


Extendsim-Based Research On Transport Process Optimization Of Emergency Cold-Chain Logistics, Ran Zhang 2012 World Maritime University

Extendsim-Based Research On Transport Process Optimization Of Emergency Cold-Chain Logistics, Ran Zhang

World Maritime University Dissertations

No abstract provided.


The Rationality Study On Capacity Allocation For Cscl’S Asia-Europe Route, Yan Zhou 2012 World Maritime University

The Rationality Study On Capacity Allocation For Cscl’S Asia-Europe Route, Yan Zhou

World Maritime University Dissertations

No abstract provided.


Rough-Cut Capacity Planning In Multimodal Freight Transportation Networks, Robert B. Hartlage 2012 Air Force Institute of Technology

Rough-Cut Capacity Planning In Multimodal Freight Transportation Networks, Robert B. Hartlage

Theses and Dissertations

A main challenge in transporting cargo for United States Transportation Command (USTRANSCOM) is in mode selection or integration. Demand for cargo is time sensitive and must be fulfilled by an established due date. Since these due dates are often inflexible, commercial carriers are used at an enormous expense, in order to fill the gap in organic transportation asset capacity. This dissertation develops a new methodology for transportation capacity assignment to routes based on the Resource Constrained Shortest Path Problem (RCSP). Routes can be single or multimodal depending on the characteristics of the network, delivery timeline, modal capacities, and costs. The …


A Model For Optimizing The Allocation Of Ethanol Production In The U.S., Anali Huggins 2012 University of Nebraska-Lincoln

A Model For Optimizing The Allocation Of Ethanol Production In The U.S., Anali Huggins

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

In the last five years, fuel prices have fluctuated from 2.86$/gallon to 3.87$/gallon which represents an increase of 35%. This situation has collocated the ethanol manufacturing in an advantageous situation. However, a major problem that is faced by the ethanol producers is the high cost of transportation. The objective of this thesis study is to determine the optimal allocation of ethanol production in the U.S. in 2009 that minimizes the transportation cost. This thesis is based on the application of a linear programing model. The thesis is focused on two questions. The first is the optimal allocation of ethanol between …


Locating And Protecting Facilities Subject To Random Disruptions And Attacks, Hugh Medal 2012 University of Arkansas, Fayetteville

Locating And Protecting Facilities Subject To Random Disruptions And Attacks, Hugh Medal

Graduate Theses and Dissertations

Recent events such as the 2011 Tohoku earthquake and tsunami in Japan have revealed the vulnerability of networks such as supply chains to disruptive events. In particular, it has become apparent that the failure of a few elements of an infrastructure system can cause a system-wide disruption. Thus, it is important to learn more about which elements of infrastructure systems are most critical and how to protect an infrastructure system from the effects of a disruption. This dissertation seeks to enhance the understanding of how to design and protect networked infrastructure systems from disruptions by developing new mathematical models and …


Optimization Models And Algorithms For Truckload Relay Network Design, Hector Andres Vergara Arteaga 2012 University of Arkansas, Fayetteville

Optimization Models And Algorithms For Truckload Relay Network Design, Hector Andres Vergara Arteaga

Graduate Theses and Dissertations

Driver turnover is a significant problem for full truckload (TL) carriers that operate using point-to-point (PtP) dispatching. The low quality of life of drivers due to the long periods of time they spend away from home is usually identified as one of the main reasons for the high turnover. In contrast, driver turnover is not as significant for less-than-truckload (LTL) carriers that use hub-and-spoke transportation networks which allow drivers to return home more frequently. Based on the differences between TL and LTL, the use of a relay network (RN) has been proposed as an alternative dispatching method for TL transportation …


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