Engineering Commons^™

Determining The Global Maximum Biofuel Production Potential Without Conflicting With Food And Feed Consumption, Watcharapol Pumkaew

All Theses

This study tries to resolve the competition between food and biofuel by balancing the allocation between food and feed areas and biofuel areas for the entire world. The maximum energy production is calculated by determining the theoretical amount of energy that can be grown, once food and feed consumption is taken into account, based on the assumption that unprotected grass and woody lands and forest lands can be converted into cultivated lands. The total optimum land area for biofuel energy, 4,926.49 Mha, consists of corn, rapeseed, sugar beet, sugar cane, and grasses. When considering energy conversion efficiency, the maximum energy …

Minimizing Base Column Demands In Multi-Story Buckling Restrained Braced Frames Using Genetic Algorithms, Christopher Hiroshi Yeates

Theses and Dissertations

Most structural optimization procedures focus on minimizing the total volume of steel in an attempt to reduce overall costs. However, many other factors can have an effect on the overall cost of a structure. Base column demands in particular, can affect base plate sizes, anchorage, and foundation design. Researchers have found that present methods for estimating column demands are too conservative. Nonlinear time history analyzes were conducted on buckling-restrained braced frames of six heights. Optimized results were found considering three ductility constraints and two optimization objectives. The two optimization objectives were minimized total brace area and minimized base column demands. …

Retrieval Of Aerosol Mass Concentration From Elastic Lidar Data, Christian C. Marchant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Agricultural aerosol sources can contribute significantly to air pollution in many regions of the country. Characterization of the aerosol emissions of agricultural operations is required to establish a scientific basis for crafting regulations concerning agricultural aerosols. A new lidar instrument for measuring aerosol emissions is described, as well as two new algorithms for converting lidar measurements into aerosol concentration data. The average daily aerosol emission rate is estimated from a dairy using lidar.

The Aglite Lidar is a portable scanning lidar for mapping the concentration of particulate matter from agricultural and other sources. The instrument is described and performance and …

The Conversion Of Low-Grade Heat Into Power Using Supercritical Rankine Cycles, Huijuan Chen

USF Tampa Graduate Theses and Dissertations

Low-grade heat sources, here defined as below 300 ºC, are abundantly available as industrial waste heat, solar thermal, and geothermal, to name a few. However, they are under-exploited for conversion to power because of the low efficiency of conversion. The utilization of low-grade heat is advantageous for many reasons. Technologies that allow the efficient conversion of low-grade heat into mechanical or electrical power are very important to develop.

This work investigates the potential of supercritical Rankine cycles in the conversion of low-grade heat into power. The performance of supercritical Rankine cycles is studied using ChemCAD linked with customized excel macros …

Optimization Of Basic And Reactive Dye Uptakes In Binary Dye Solution Using Statistical Experimental Methodology, Siew-Teng Ong, Weng-Nam Lee, Pei-Sin Keng, Siew-Ling Lee, Yung-Tse Hung

Civil and Environmental Engineering Faculty Publications

In the present study, the optimum adsorption conditions for the uptake of methylene blue (MB) and reactive orange 16 (RO16) in binary dye solution by ethylenediamine tetraacidic acid (EDTA) modified rice hulls was studied. By using the Plackett-Burman design, the significant variables in affecting the MB and RO16 uptake in binary dye solution were identified as pH and contact time. The combined effects of interaction between the variables were determined using response surface methodology (RSM). The model predicted that at optimum conditions: pH 6.77 and contact time of 205.58 min, the MB uptake greater than 95% could be obtained. As …

Potassium Hydroxide Catalyst Supported On Palm Shell Activated Carbon For Transesterification Of Palm Oil, Abdul Aziz Abdul Raman

Abdul Aziz Abdul Raman

In this study, potassium hydroxide catalyst supported on palm shell activated carbon was developed for transesterification of palm oil. The Central Composite Design (CCD) of the Response Surface Methodology (RSM) was employed to investigate the effects of reaction temperature, catalyst loading and methanol to oil molar ratio on the production of biodiesel using activated carbon supported catalyst. The highest yield was obtained at 64.1 °C reaction temperature, 30.3 wt.% catalyst loading and 24:1 methanol to oil molar ratio. The physical and chemical properties of the produced biodiesel met the standard specifications. This study proves that activated carbon supported potassium hydroxide …

Risk-Based Seismic Design Optimization Of Steel Building Systems With Passive Damping Devices, Junshan Liu

Dissertations (1934 -)

Nonlinear time history analysis software and an optimization algorithm for automating design of steel frame buildings with and without supplemental passive damping systems using the risk- or performance-based seismic design philosophy are developed in this dissertation. The software package developed is suitable for conducting dynamic analysis of 2D steel framed structures modeled as shear buildings with linear/nonlinear viscous and viscoelastic dampers. Both single degree of freedom (SDOF) and multiple degree of freedom (multistory or MDOF) shear-building systems are considered to validate the nonlinear analysis engine developed. The response of both un-damped and damped structures using the 1940 EI Centro (Imperial …

Optimized Waveform Relaxation Solution Of Electromagnetic And Circuit Problems, Martin J. Gander, Albert E. Ruehli

Electrical and Computer Engineering Faculty Research & Creative Works

New algorithms are needed to solve electromagnetic problems using today's widely available parallel processors. In this paper, we show that applying the optimized waveform relaxation approach to a partial element equivalent circuit will yield a powerful technique for solving electromagnetic problems with the potential for a large number of parallel processor nodes.

Economic Analysis Of End-Of-Life Computer Systems In Educational Institutions, Elif A. Kizilkaya, Surendra M. Gupta, Dincer Mehmet

Surendra M. Gupta

In this paper we address the operational and economical aspects of EOL computer systems at educational institutions. To this end we present an actual case study of a major university in Boston and provide an economical analysis of different options such as disposal, disassembly, recycling, reuse and re-sale of these systems. We recommend a new procedure that will improve the collection and handling processes leading to a structured decision making methodology.

Inventory Balancing Of Post-Usage Components Of A Disassembly Line, Surendra M. Gupta, Badr O. Johar

Surendra M. Gupta

In recent years, disassembly has gained a lot of attention due to its role in efficiently recovering valuable materials, parts, and subassemblies from end of life (EOL) products. This is due to the rigid environmental legislation, the economical and environmental benefits from reusing primary materials instead of virgin resources and the increase in environmental awareness and concerns of the consumers. However, the practice of recovering components and materials is challenging, as there are many associated complications that are unique to the disassembly process such as monitoring and controlling the inventory of core products and disassembled parts and the ability to …

A Stochastic Product Priority Optimization Method For Remanufacturing System Based On Genetic Algorithm, Xiong Xiong

Theses and Dissertations - UTB/UTPA

Increasing number of manufacturers are developing remanufacturing facilities to recover end-of-life products for product/component reuse and material recycling while the high uncertainty pattern of returned products complicates the production planning. In this thesis a stochastic production priority optimization method, considering various priority concerns for remanufacturing systems is developed. Priority ranking and matching algorithm is developed to determine the priority rule, using thirteen weighting factors. Queueing models are developed to formulate the objective function, a genetic algorithm is then developed to search optimal solution under different business configurations. Result of this research will provide insights to priority assignment mechanism, which in …

Expanding Horizons With Chameleon: Team Missouri's Innovative Home Automation System, Bryan Glass, Ben Brannon, Katie Grantham, Stuart Werner Baur

Engineering Management and Systems Engineering Faculty Research & Creative Works

Team Missouri's 2009 Solar Decathlon entry featured a revolutionary home automation system, Chameleon, promoting both convenience and energy savings. This was accomplished using the typical controls of a convenience based automation system, while maintaining user set points, such as a home's ambient temperature, in the most energy efficient manner. Environmental features of the system include controls for home heating, ventilation and air conditioning, lighting, windows, shades, appliances, indoor air quality, as well as indoor and outdoor irrigation. Further analysis and refinement to the prototype system displayed at the competition is also presented in this paper.

Modified Sequential Kriging Optimization For Multidisciplinary Complex Product Simulation, Wang Hao, Wang Shaoping, Mileta M. Tomovic

Engineering Technology Faculty Publications

Directing to the high cost of computer simulation optimization problem, Kriging surrogate model is widely used to decrease the computation time. Since the sequential Kriging optimization is time consuming, this article extends the expected improvement and put forwards a modified sequential Kriging optimization (MSKO). This method changes the twice optimization problem into once by adding more than one point at the same time. Before re-fitting the Kriging model, the new sample points are verified to ensure that they do not overlap the previous one and the distance between two sample points is not too small. This article presents the double …

Optimizing Integrated Service For A Transit Route With Heterogeneous Demand, Yavuz Yusuf Ulusoy

Dissertations

The methodology developed in this dissertation attempts to optimize integrated service that minimizes the total cost, including user and supplier costs, of a transit route with heterogeneous demand. While minimizing total cost, a set of practical constraints, such as capacity, operable fleet size and frequency conservation, are considered.

The research problem is presented in three scenarios, consisting of various service patterns (e.g., all-stop, short-turn and express) under heterogeneous demand. A logit-based model was used to estimate passenger transfer demand. An exhaustive search method was developed to find the optimal solutions for a simplified transit route with six stops, and a …

Improving Analytical Travel Time Estimation For Transportation Planning Models, Chenxi Lu

FIU Electronic Theses and Dissertations

This dissertation aimed to improve travel time estimation for the purpose of transportation planning by developing a travel time estimation method that incorporates the effects of signal timing plans, which were difficult to consider in planning models. For this purpose, an analytical model has been developed. The model parameters were calibrated based on data from CORSIM microscopic simulation, with signal timing plans optimized using the TRANSYT-7F software. Independent variables in the model are link length, free-flow speed, and traffic volumes from the competing turning movements. The developed model has three advantages compared to traditional link-based or node-based models. First, the …

Standby Leakage Power Reduction Technique For Nanoscale Cmos Vlsi Systems, Heungjun Jeon, Yong-Bin Kim, Minsu Choi

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a novel low-power design technique is proposed to minimize the standby leakage power in nanoscale CMOS very large scale integration (VLSI) systems by generating the adaptive optimal reverse body-bias voltage. The adaptive optimal body-bias voltage is generated from the proposed leakage monitoring circuit, which compares the subthreshold current (I_SUB) and the band-to-band tunneling (BTBT) current (I_BTBT). The proposed circuit was simulated in HSPICE using 32-nm bulk CMOS technology and evaluated using ISCAS85 benchmark circuits at different operating temperatures (ranging from 25°C to 100°C). Analysis of the results shows a maximum of 551 and …

Decentralized Coordination Of Multiple Autonomous Vehicles, Yongcan Cao

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation focuses on the study of decentralized coordination algorithms of multiple autonomous vehicles. Here, the term decentralized coordination is used to refer to the behavior that a group of vehicles reaches the desired group behavior via local interaction. Research is conducted towards designing and analyzing distributed coordination algorithms to achieve desired group behavior in the presence of none, one, and multiple group reference states.

Decentralized coordination in the absence of any group reference state is a very active research topic in the systems and controls society. We first focus on studying decentralized coordination problems for both single-integrator kinematics and …

Methods To Streamline Laminate Composite Design, Analysis, And Optimization, Ammon Ikaika No Kapono Hepworth

Theses and Dissertations

Advanced composite materials have seen major market growth in recent years due to their high strength and low weight properties. These materials are often made using a process that creates a composite laminate by stacking several composite layers together. However, the design, analysis and optimization of laminate composite materials are often a labor intensive process when done manually. This thesis discusses CAD independent algorithms that are integrated into commercial CAD tools to streamline these processes. Methods have been developed to automatically create 3D ply geometry for a laminate composite lay-up, streamline the creation of a laminate composite finite element model …

Random Approach To Optimization Of Overlay Public-Resource Computing Systems, Grzegorz Chmaj, Krzysztof Walkowiak

Electrical & Computer Engineering Faculty Research

The growing need for computationally demanding systems triggers the development of various network-oriented computing systems organized in a distributed manner. In this work we concentrate on one kind of such systems, i.e. public-resource computing systems. The considered system works on the top of an overlay network and uses personal computers and other relatively simple electronic equipment instead of supercomputers. We assume that two kinds of network flows are used to distribute the data in the public-resource computing systems: unicast and peer-to-peer. We formulate an optimization model of the system. After that we propose random algorithms that optimize jointly the allocation …

Energy Audit And Optimization For "Arches Etc.", James Ross Dixon

Industrial and Manufacturing Engineering

Arches etc. is a San Diego business, which specializes in the manufacture, distribution, and installation of custom designed doors, windows, mouldings, and hardware. Due to the recent economic downturn, which has hindered the construction industry, Arches etc. believed that an analysis and optimization of their energy usage would provide additional assistance towards their goal to lower overhead and maintain current operations.

To begin this task, a comprehensive energy audit was conducted to establish an initial state from which to base improvements. Arches etc.’s current monthly utility bill averages $996, which solidifies the accuracy of this project’s performed energy audit, estimating …

Optimizing The Rearrangement Process In A Dedicated Warehouse, Hector J. Carlo, German E. Giraldo

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

Determining the optimal storage assignment for products in a dedicated warehouse has been addressed extensively in the Facility Logistics literature. However, the process of implementing a particular storage assignment given the current location of products has not received much attention in the existing literature. Typically, warehouses use downtime or overtime to remove products from their current location and move them to the suggested location. This work presents the Rearrange-While-Working (RWW) policy to optimize the process of rearranging a dedicated warehouse. The RWW policy seeks to relocate products in a warehouse from the initial arrangement to the optimal arrangement while serving …

A Systematic Optimization And Operation Of Central Chilling Systems For Energy Efficiency And Sustainability, Zhenjun Ma, Shengwei Wang

Faculty of Engineering - Papers (Archive)

This paper presents an optimization strategy for optimal control and operation of building central chilling systems in order to minimize their energy consumption and provide improved control performance. The strategy is formulated using a systematic approach, in which the characteristics and interactions among the components and subsystems in the central chilling system are considered. The simplified models of major components are used in the strategy as the performance predictors to estimate the system energy performance and responses to the changes of control settings and working conditions. To ensure the models to provide reliable estimates when the working condition changes, the …

A Λ-Cut And Goal-Programming-Based Algorithm For Fuzzy-Linear Multiple-Objective Bilevel Optimization, Ya Gao, Guangquan Zhang, Jun Ma, Jie Lu

Faculty of Engineering and Information Sciences - Papers: Part A

Bilevel-programming techniques are developed to handle decentralized problems with two-level decision makers, which are leaders and followers, who may have more than one objective to achieve. This paper proposes a λ-cut and goal-programming-based algorithm to solve fuzzy-linear multiple-objective bilevel (FLMOB) decision problems. First, based on the definition of a distance measure between two fuzzy vectors using λ-cut, a fuzzy-linear bilevel goal (FLBG) model is formatted, and related theorems are proved. Then, using a λ-cut for fuzzy coefficients and a goal-programming strategy for multiple objectives, a λ-cut and goal-programming-based algorithm to solve FLMOB decision problems is presented. A case study for …

Computational Fluid Dynamic Optimization And Design For The Airborne Laser System, Matthew James Opgenorth

Electronic Theses and Dissertations

The Airborne Laser (ABL) was designed to destroy any ballistic missile shortly after launch that could be a threat to the United States and its allies. The ABL uses several lasers to accomplish the destruction of the ballistic missile, most notably the high powered Chemical Oxygen Iodine Laser (COIL). The COIL is a complex device that could be improved upon in several areas that will result in overall weight reduction, refinement of beam quality, and increased magazine capacity.

This dissertation presents novel design and optimization techniques coupled with fluid dynamics to improve the performance of the COIL system. The focus …

An Approach Based On Particle Swarm Computation To Study The Nanoscale Dg Mosfet-Based Circuits, Fayacl Djeffal, Toufik Bendib, Redha Benzid, Abdelhamid Benhaya

Turkish Journal of Electrical Engineering and Computer Sciences

The analytical modeling of nanoscale Double-Gate MOSFETs (DG) requires generally several necessary simplifying assumptions to lead to compact expressions of current-voltage characteristics for nanoscale CMOS circuits design. Further, progress in the development, design and optimization of nanoscale devices necessarily require new theory and modeling tools in order to improve the accuracy and the computational time of circuits' simulators. In this paper, we propose a new particle swarm strategy to study the nanoscale CMOS circuits. The latter is based on the 2-D numerical Non-Equilibrium Green's Function (NEGF) simulation and a new extended long channel DG MOSFET compact model. Good agreement between …

Optimization, An Important Stage Of Engineering Design, Todd R. Kelley

Publications

The presents information on optimization, an important stage of engineering design. Criteria and design constraints are used in the optimization stage of the engineering design process to allow the designer to locate the optimal solution. Before initiating a prototype work, both analysis and optimization are done in designing a product. Optimization is done to create the best design relative to a set of prioritized criteria or constraints, including maximizing factors such as productivity, strength, reliability, longevity, efficiency and utilization.

Indiana Pavement Preservation Program, Ghim Ping (Raymond) Ong, Tommy E. Nantung, Kumares C. Sinha

JTRP Technical Reports

State highway agencies are facing immense pressure to maintain roads at acceptable levels amidst the challenging financial and economic situations. In recent years, pavement preservation has been sought as a potential alternative for managing the pavement assets, believing that it would provide a cost-effective solution in maintaining infrastructural conditions and meeting user expectations. This study explores the potential of pavement preservation concepts in managing the agency‘s pavement assets by attempting to integrate pavement preservation considerations within the network-level pavement management system. Several elements are studied in the report: (i) determining triggers for pavement preservation treatments for use in a PMS, …

Optimum Design Of Cable-Stayed Bridges, Mahmoud M. Hassan

Digitized Theses

Owing to their excellent structural characteristics, aesthetic appearance, low maintenance cost, and efficient use of structural materials, cable-stayed bridges have gained much popularity in recent decades. Stay cables of a cable stayed bridge are post-tensioned to counteract the effect of the bridge dead load. The solution for an optimum distribution of post-tensioning cable forces is considered one of the most important and difficult tasks in the design of cable-stayed bridges. A novel approach that utilizes the finite element method, B-spline curves, and real coded genetic algorithm to determine the global optimum post-tensioning cable forces is developed. The effect of geometric …