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2017

Optimization

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Full-Text Articles in Engineering

Load Balancing With Energy Storage Systems Based On Co-Simulation Of Multiple Smart Buildings And Distribution Networks, Shaun Duerr, Cristinel Ababei, Dan M. Ionel Dec 2017

Load Balancing With Energy Storage Systems Based On Co-Simulation Of Multiple Smart Buildings And Distribution Networks, Shaun Duerr, Cristinel Ababei, Dan M. Ionel

Electrical and Computer Engineering Faculty Research and Publications

In this paper, we present a co-simulation framework that combines two main simulation tools, one that provides detailed multiple building energy simulation ability with Energy-Plus being the core engine, and the other one that is a distribution level simulator, Matpower. Such a framework can be used to develop and study district level optimization techniques that exploit the interaction between a smart electric grid and buildings as well as the interaction between buildings themselves to achieve energy and cost savings and better energy management beyond what one can achieve through techniques applied at the building level only. We propose a heuristic …


Indonesia’S Municipal Solid Waste 3r And Waste To Energy Programs, Farizal Farizal, Radityo Aji, Amar Rachman, Nasruddin Nasruddin, Teuku Meurah Indra Mahlia Dec 2017

Indonesia’S Municipal Solid Waste 3r And Waste To Energy Programs, Farizal Farizal, Radityo Aji, Amar Rachman, Nasruddin Nasruddin, Teuku Meurah Indra Mahlia

Makara Journal of Technology

Like most cities in the world, population in Indonesia continues to grow every year. Problems that can arise from this are the increasing amount of municipal solid waste (MSW) production and the growing demand for electricity. To deal with the problems, Indonesian government runs 3R (Reduce, Reuse and Recycle) and WTE (Waste to Energy) Programs simultaneously. 3R program aims to reduce the number of waste, while WTE program aims to generate electricity as an alternative energy source. This study aims to find out the optimal proportion of MSW treated through the 3R and WTE programs. For the purpose, a goal …


Whitespace Exploration, Jason Lloyd Daniel Dec 2017

Whitespace Exploration, Jason Lloyd Daniel

Master's Theses

As engineering systems grow in complexity so too must the design tools that we use evolve and allow for decision makers to efficiently ask questions of their model and obtain meaningful answers. The process of whitespace exploration has recently been developed to aid in engineering design and provide insight into a design space where traditional design exploration methods may fail. In an effort to further the research and development of whitespace exploration algorithms, a software package called Thalia has been created to allow for automated data collection and experimentation with the whitespace exploration methodology.

In this work, whitespace exploration is …


Efficient Gate System Operations For A Multipurpose Port Using Simulation Optimization, Ketki Kulkarni, Trong Khiem Tran, Hai Wang, Hoong Chuin Lau Dec 2017

Efficient Gate System Operations For A Multipurpose Port Using Simulation Optimization, Ketki Kulkarni, Trong Khiem Tran, Hai Wang, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

Port capacity is determined by three major infrastructural resources namely, berths, yards and gates. Theadvertised capacity is constrained by the least of the capacities of the three resources. While a lot ofattention has been paid to optimizing berth and yard capacities, not much attention has been given toanalyzing the gate capacity. The gates are a key node between the land-side and sea-side operations in anocean-to-cities value chain. The gate system under consideration, located at an important port in an Asiancity, is a multi-class parallel queuing system with non-homogeneous Poisson arrivals. It is hard to obtaina closed form analytic approach for …


A Selective-Discrete Particle Swarm Optimization Algorithm For Solving A Class Of Orienteering Problems, Aldy Gunawan, Vincent F. Yu, Perwira Redi, Parida Jewpanya, Hoong Chuin Lau Dec 2017

A Selective-Discrete Particle Swarm Optimization Algorithm For Solving A Class Of Orienteering Problems, Aldy Gunawan, Vincent F. Yu, Perwira Redi, Parida Jewpanya, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

This study addresses a class of NP-hard problem called the Orienteering Problem (OP), which belongs to a well-known class of vehicle routing problems. In the OP, a set of nodes that associated with a location and a score is given. The time required to travel between each pair of nodes is known in advance. The total travel time is limited by a predetermined time budget. The objective is to select a subset of nodes to be visited that maximizes the total collected score within a path. The Team OP (TOP) is an extension of OP that incorporates multiple paths. Another …


Design And Analysis Of Compressed Air Power Harvesting Systems, Zachary James Sadler Dec 2017

Design And Analysis Of Compressed Air Power Harvesting Systems, Zachary James Sadler

Theses and Dissertations

Procedure for site discovery, system design, and optimization of power harvesting systems is developed with an emphasis on application to air compressors. Limitations for the usage of infrared pyrometers is evaluated. A system of governing equations for thermoelectric generators is developed. A solution method for solving the system of equations is created in order to predict power output from the device. Payback analysis is proposed for determining economic viability. A genetic algorithm is used to optimize the power harvesting system payback with changing quantities and varieties of thermoelectric generators, as well as the back work put into cooling the thermoelectric …


Design And Analysis Of Compressed Air Power Harvesting Systems, Zachary James Sadler Dec 2017

Design And Analysis Of Compressed Air Power Harvesting Systems, Zachary James Sadler

Theses and Dissertations

Procedure for site discovery, system design, and optimization of power harvesting systems is developed with an emphasis on application to air compressors. Limitations for the usage of infrared pyrometers is evaluated. A system of governing equations for thermoelectric generators is developed. A solution method for solving the system of equations is created in order to predict power output from the device. Payback analysis is proposed for determining economic viability. A genetic algorithm is used to optimize the power harvesting system payback with changing quantities and varieties of thermoelectric generators, as well as the back work put into cooling the thermoelectric …


Calibrating And Evaluating Dynamic Rule-Based Transit-Signal-Priority Control Systems In Urban Traffic Networks, Md Didarul Alam Nov 2017

Calibrating And Evaluating Dynamic Rule-Based Transit-Signal-Priority Control Systems In Urban Traffic Networks, Md Didarul Alam

Civil and Environmental Engineering Dissertations

Setting the traffic controller parameters to perform effectively in real-time is a challenging task, and it entails setting several parameters to best suit some predicted traffic conditions. This study presents the framework and method that entail the application of the Response Surface Methodology (RSM) to calibrate the parameters of any control system incorporating advanced traffic management strategies (e.g., the complex integrated traffic control system developed by Ahmed and Hawas). The integrated system is a rule-based heuristic controller that reacts to specific triggering conditions, such as identification of priority transit vehicle, downstream signal congestion, and incidents by penalizing the predefined objective …


Water Resources Adaptation To Climate And Demand Change In The Potomac River, James H. Stagge, Glenn E. Moglen Sep 2017

Water Resources Adaptation To Climate And Demand Change In The Potomac River, James H. Stagge, Glenn E. Moglen

Publications

The effects of climate change are increasingly considered in conjunction with changes in water demand and reservoir sedimentation in forecasts of water supply vulnerability. Here, the relative effects of these factors are evaluated for the Washington, DC metropolitan area water supply for the near (2010 to 2039), intermediate (2040-2069), and distant future (2070 to 2099) by repeated water resources model simulations. This system poses water management challenges due to long water delivery travel times that increase uncertainty, multiple water jurisdictions that constrain potential decisions, and future scenarios that simultaneously increase demand and decrease water supply during the critical summer period. …


Loading Time Flexibility In Cross-Docking Systems, Dincer Konur, Mihalis M. Golias Sep 2017

Loading Time Flexibility In Cross-Docking Systems, Dincer Konur, Mihalis M. Golias

Engineering Management and Systems Engineering Faculty Research & Creative Works

In this study, we investigate truck-to-door assignment problem for loading outgoing trucks in a cross-docking system with flexible handling times. Specifically, a truck's loading time depends on the number of workers assigned to the outbound door, where the truck is being loaded. An optimization problem is formulated to jointly determine the number of workers and the trucks to be loaded at each door. The resulting problem is a nonlinear integer programming model. Due to the complexity of this model, two evolutionary heuristic methods are proposed for solution. First heuristic method is based on truck assignments while the second heuristic is …


Simplex Solutions For Optimal Control Flight Paths In Urban Environments, Michael D. Zollars, Richard G. Cobb, David J. Grymin Aug 2017

Simplex Solutions For Optimal Control Flight Paths In Urban Environments, Michael D. Zollars, Richard G. Cobb, David J. Grymin

Faculty Publications

This paper identifies feasible fight paths for Small Unmanned Aircraft Systems in a highly constrained environment. Optimal control software has long been used for vehicle path planning and has proven most successful when an adequate initial guess is presented flight to an optimal control solver. Leveraging fast geometric planning techniques, a large search space is discretized into a set of simplexes where a Dubins path solution is generated and contained in a polygonal search corridor free of path constraints. Direct optimal control methods are then used to determine the optimal flight path through the newly defined search corridor. Two scenarios …


Pepso: Reducing Electricity Usage And Associated Pollution Emissions Of Water Pumps, Seyed Mohsen Sadatiyan Abkenar, Carol J. Miller Aug 2017

Pepso: Reducing Electricity Usage And Associated Pollution Emissions Of Water Pumps, Seyed Mohsen Sadatiyan Abkenar, Carol J. Miller

Civil and Environmental Engineering Faculty Research Publications

Using metaheuristic optimization methods has enabled researchers to reduce the electricity consumption cost of small water distribution systems (WDSs). However, dealing with complicated WDSs and reducing their environmental footprint remains a challenge. In this study a multi-objective version of Pollution Emission Pump Station Optimization tool (PEPSO) is introduced that can reduce the electricity cost and pollution emissions (associated with the energy consumption) of pumps of WDSs. PEPSO includes a user-friendly graphical interface and a customized version of the non-dominated sorting genetic algorithm. A measure that is called “Undesirability Index” (UI) is defined to assist the search for a promising optimization …


Treatment Of Oil Sands Process-Affected Water Using Activated And Surface Modified Petroleum Coke For Organic Compounds Recovery, Hojatallah Seyedy Niasar Aug 2017

Treatment Of Oil Sands Process-Affected Water Using Activated And Surface Modified Petroleum Coke For Organic Compounds Recovery, Hojatallah Seyedy Niasar

Electronic Thesis and Dissertation Repository

Each day large volumes of oil sands process-affected water (OSPW) are being produced during the extraction of bitumen in oil sands industry in northern Alberta. OSPW contains different polyaromatic hydrocarbons which not only are the major source of toxicity in OSPW, but also create operational problems such as corrosion of the equipment during bitumen recovery process. Therefore, these compounds need to be removed prior to the recycle of the OSPW. In this research, petroleum coke (PC) as an abundant, inexpensive adsorbent was selected as an adsorbent for recovery of chemicals from OSPW. The surface area and adsorption capacity of PC …


Applications Of Cfd Simulations On Chemical Processing Equipment Designs, Gongqiang He Aug 2017

Applications Of Cfd Simulations On Chemical Processing Equipment Designs, Gongqiang He

LSU Doctoral Dissertations

The objective of this work is to achieve process intensification by seeking optimal equipment design with CFD investigations. In this work, two projects on chemical equipment design have been discussed.

The first project is on design and optimization of fractal distributor in a novel ion-exchanger. Flow distributors are adopted extensively by chemical industry to distribute an incoming process stream uniformly to the downstream equipment. Currently, the performance of chemical equipment installed with conventional distributor is severely undermined due to poor flow distribution. For conventional distributors such as spray nozzle distributors, their design concept is based on maintaining very high pressure …


Towards Food Service Sustainability In Suburban Environments By Optimally Locating Shared Anaerobic Digester Units, Rebecca Loraamm, Joni Downs, Robert Alonso Bair, Daniel Yeh Aug 2017

Towards Food Service Sustainability In Suburban Environments By Optimally Locating Shared Anaerobic Digester Units, Rebecca Loraamm, Joni Downs, Robert Alonso Bair, Daniel Yeh

Suburban Sustainability

Anaerobic digestion is an effective method for reducing food waste at the consumer level. Drawbacks associated with this strategy include high construction costs for multiple digester units and limited public awareness of the method’s commercial potential. Given the large scale problem of food waste, an approach establishing community partnerships between local businesses and primary schools is offered to combat the problem of food waste. Optimizing the placement of shared digester units enabling utilization by multiple stakeholders is the suggested mitigation method. This research explores application of the p-median problem to determine the set of optimal sites for shared anaerobic digester …


Optimization And Control Of Production Of Graphene, Atharva Hans, Nimish M. Awalgaonkar, Majed Alrefae, Ilias Bilionis, Timothy S. Fisher Aug 2017

Optimization And Control Of Production Of Graphene, Atharva Hans, Nimish M. Awalgaonkar, Majed Alrefae, Ilias Bilionis, Timothy S. Fisher

The Summer Undergraduate Research Fellowship (SURF) Symposium

Graphene is a 2-dimensional element of high practical importance. Despite its exceptional properties, graphene’s real applications in industrial or commercial products have been limited. There are many methods to produce graphene, but none has been successful in commercializing its production. Roll-to-roll plasma chemical vapor deposition (CVD) is used to manufacture graphene at large scale. In this research, we present a Bayesian linear regression model to predict the roll-to-roll plasma system’s electrode voltage and current; given a particular set of inputs. The inputs of the plasma system are power, pressure and concentration of gases; hydrogen, methane, oxygen, nitrogen and argon. This …


Flight Risk Management And Crew Reserve Optimization, Ying Zhang Aug 2017

Flight Risk Management And Crew Reserve Optimization, Ying Zhang

Doctoral Dissertations

There are two key concerns in the development process of aviation. One is safety, and the other is cost. An airline running with high safety and low cost must be the most competitive one in the market. This work investigates two research efforts respectively relevant to these two concerns.

When building support of a real time Flight Risk Assessment and Mitigation System (FRAMS), a sequential multi-stage approach is developed. The whole risk management process is considered in order to improve the safety of each flight by integrating AHP and FTA technique to describe the framework of all levels of risks …


Specification Of Mixed Logit Models Using An Optimization Approach, Cristian David Arteaga Sanchez Aug 2017

Specification Of Mixed Logit Models Using An Optimization Approach, Cristian David Arteaga Sanchez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Mixed logit models are a widely-used tool for studying discrete outcome problems. Modeling development entails answering three important questions that highly affect the quality of the specification: (i) what variables are considered in the analysis? (ii) what are going to be the coefficients for these variables? and (iii) what density function these coefficients will follow? The literature provides guidance; however, a strong statistical background and an ad hoc search process are required to obtain the best model specification. Knowledge of the problem context and data is required. Given a dataset including discrete outcomes and associated characteristics the problem to be …


Optimization Of Prosthetic Hands: Utilizing Modularity To Improve Grip Force, Grasp, And Versatility, Jordan William Harris Aug 2017

Optimization Of Prosthetic Hands: Utilizing Modularity To Improve Grip Force, Grasp, And Versatility, Jordan William Harris

UNLV Theses, Dissertations, Professional Papers, and Capstones

It has been demonstrated that although many varieties of upper limb prosthetics exist, commercially available prosthetics are outdated and unsatisfactory. Ineffectiveness and limitations have led to some prosthesis wearers having to own multiple devices, whereas others have given up on them entirely. Even though ample research has been conducted to design and test new hand designs, the industry appears to rest in an overall stagnated state.

It was proposed here, that one problem with prosthetic research is an excess of variables involved in testing, and therefore the improper application of the scientific method. It seems that each time a research …


Improving The Floris Wind Plant Model For Compatibility With Gradient-Based Optimization, Jared Thomas, Pieter Gebraad, Andrew Ning Aug 2017

Improving The Floris Wind Plant Model For Compatibility With Gradient-Based Optimization, Jared Thomas, Pieter Gebraad, Andrew Ning

Faculty Publications

The FLOw Redirection and Induction in Steady-state (FLORIS) model, a parametric wind turbine wake model that predicts steady state wake characteristics based on wind turbine position and yaw angle, was developed for optimization of control settings and turbine locations. This paper provides details on the recent changes made to the FLORIS model to make the model more suitable for gradient-based optimization. Changes to the FLORIS model were made to remove discontinuities and add curvature to regions of non-physical zero gradient. Exact gradients for the FLORIS model were obtained using algorithmic differentiation. A set of three case studies demonstrate that using …


Radiative Heat Transfer Analysis Of Railroad Bearings For Wayside Hot-Box Detector Optimization, Arthur Mealer, Constantine Tarawneh, Stephen Crown Jul 2017

Radiative Heat Transfer Analysis Of Railroad Bearings For Wayside Hot-Box Detector Optimization, Arthur Mealer, Constantine Tarawneh, Stephen Crown

Mechanical Engineering Faculty Publications and Presentations

The railroad industry utilizes wayside detection systems to monitor the temperature of freight railcar bearings in service. The wayside hot-box detector (HBD) is a device that sits on the side of the tracks and uses a non-contact infrared sensor to determine the temperature of the train bearings as they roll over the detector. Various factors can affect the temperature measurements of these wayside detection systems. The class of the railroad bearing and its position on the axle relative to the position of the wayside detector can affect the temperature measurement. That is, the location on the bearing cup where the …


An Optimization Model For Operating Room Scheduling To Reduce Blocking Across The Perioperative Process, Amin Abedini, Wei Li, Honghan Ye Jul 2017

An Optimization Model For Operating Room Scheduling To Reduce Blocking Across The Perioperative Process, Amin Abedini, Wei Li, Honghan Ye

Mechanical Engineering Faculty Publications

Operating room (OR) scheduling is important. Because of increasing demand for surgical services, hospitals must provide high quality care more efficiently with limited resources. When constructing the OR schedule, it is necessary to consider the availability of downstream resources, such as intensive care unit (ICU) and post anaesthesia care unit (PACU). The unavailability of downstream resources causes blockings between every two consecutive stages. In this paper we address the master surgical schedule (MSS) problem in order to minimize blockings between two consecutive stages. First, we present a blocking minimization (BM) model for the MSS by using integer programming, based on …


Fast Estimation Model Of Pressure-Temperature Response For Planning Focused Ultrasound Surgery, Tariq Mohammad Arif Jul 2017

Fast Estimation Model Of Pressure-Temperature Response For Planning Focused Ultrasound Surgery, Tariq Mohammad Arif

Dissertations

High Intensity Focused Ultrasound (HIFU) is becoming a widely accepted modality for extracorporeal non-invasive hyperthermia and surgical procedures. Since ultrasonic transducers need to operate in various challenging body locations, the arrangement of their array elements can be optimized to improve the capability of controlling focus intensity. In the first part of this dissertation, patterns of pressure field variations with several selected design variables (kerf, transducer element’s number and element’s width-height) are studied. These patterns indicate that there is a more suitable shape and arrangement of transducer elements in a specified area to achieve highest possible pressure. In order to obtain …


A Parametric Investigation And Optimization Of A Cylindrical Explosive Charge, Logan Ellsworth Beaver Jul 2017

A Parametric Investigation And Optimization Of A Cylindrical Explosive Charge, Logan Ellsworth Beaver

Master's Theses (2009 -)

Explosive device design has a wide impact in the space, manufacturing, military, and mining industries. As a step toward computer assisted design of explosives, an optimization framework was developed using the Design Analysis Kit for Optimization and Terrascale Applications (Dakota). This software was coupled with the hydrocode CTH. This framework was applied to three exploding cylinder models, two in 1D and one in 2D. Gradient descent, dividing rectangles, and a genetic algorithm were each applied to the one-dimensional models. Parametric studies were performed as a basis for comparison with the optimization algorithms, as well as qualifying the 1D model's accuracy. …


Multi-Population-Based Differential Evolution Algorithm For Optimization Problems, Ishani Chatterjee May 2017

Multi-Population-Based Differential Evolution Algorithm For Optimization Problems, Ishani Chatterjee

Theses

A differential evolution (DE) algorithm is an evolutionary algorithm for optimization problems over a continuous domain. To solve high dimensional global optimization problems, this work investigates the performance of differential evolution algorithms under a multi-population strategy. The original DE algorithm generates an initial set of suitable solutions. The multi-population strategy divides the set into several subsets. These subsets evolve independently and connect with each other according to the DE algorithm. This helps in preserving the diversity of the initial set. Furthermore, a comparison of combination of different mutation techniques on several optimization algorithms is studied to verify their performance. Finally, …


Cache Power Optimization Using Multiple Voltage Supplies To Exploit Read/Write Asymmetry, Dengxue Yan May 2017

Cache Power Optimization Using Multiple Voltage Supplies To Exploit Read/Write Asymmetry, Dengxue Yan

McKelvey School of Engineering Theses & Dissertations

Power consumption becomes more and more critical in computer systems nowadays. Most of the previous work has been focusing on general-purpose computational core, but optimization techniques for conventional CPU core has reached a limit. Our experimental results show that read operations in SRAM can be performed at a lower supply with much reduced power consumption compared to write operations. Based on this observation and the fact that cache, consisting mostly of SRAM, often occupies significant on-chip area of the CPU and consumes a huge portion of the CPU power, we propose a new method to reduce the power consumption of …


Electric Power System Operations With A Variable Series Reactor, Xiaohu Zhang May 2017

Electric Power System Operations With A Variable Series Reactor, Xiaohu Zhang

Doctoral Dissertations

Series FACTS devices, such as a Variable Series Reactor (VSR), have the ability to continuously regulate the transmission line reactance so as to control power ow. This research work evaluates the benefits brought by VSRs in different aspects of power system and develops efficient planning models and algorithms to provide optimal investment plan for the VSRs.

First, an optimization approach capable of finding both optimal locations and settings of VSRs under a specific operating condition is developed. The tool implements a full ac model as well as detailed models for different power system components.

Second, an optimization tool which can …


Maximum Likelihood Temperature/Emissivity Separation Of Hyperspectral Images With Gaussian Distributed Downwelling Radiance, David A. Neal May 2017

Maximum Likelihood Temperature/Emissivity Separation Of Hyperspectral Images With Gaussian Distributed Downwelling Radiance, David A. Neal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Hyperspectral images are made up of energy measurements at different wavelengths of light. The case is considered where these measurements are dependent on temperature, the self-emitted energy (emissivity), and reflected energy (downwelling radiance) from the surroundings. The process where the downwelling radiance is fixed and the temperature and emissivity are estimated is referred to as temperature/emissivity separation.

Due to the way these terms mix, for a given set of measurements, there exist many pairs of temperatures and emissivities that satisfy the model. This creates ambiguity in the solution that must be resolved for the result to have any significance.

A …


Cost And Fuel Usage Optimization Of Activating Solution Based Silica Fume Geopolymer Concrete, Lateef Najeh Assi May 2017

Cost And Fuel Usage Optimization Of Activating Solution Based Silica Fume Geopolymer Concrete, Lateef Najeh Assi

Theses and Dissertations

Development of sustainable construction materials has been the focus of research efforts worldwide in recent years. Concrete is a major construction material; hence, finding alternatives to ordinary Portland cement is of extreme importance due to high levels of carbon dioxide emissions associated with its manufacturing process. Geopolymer concrete is a potential solution; however, concerns about the high cost and the low real fuel energy efficiency are obstacles against its increase in the market share.

In this thesis, the current cost and fuel (thermal energy) usage are calculated. In addition, the cost and fuel usage were optimized based on previous experimental …


Optimization Under Uncertainty For Wake Steering Strategies, Julian Quick, Jennifer Annoni, Ryan King, Katherine Dykes, Paul Fleming, Andrew Ning May 2017

Optimization Under Uncertainty For Wake Steering Strategies, Julian Quick, Jennifer Annoni, Ryan King, Katherine Dykes, Paul Fleming, Andrew Ning

Faculty Publications

Wind turbines in a wind power plant experience significant power losses because of aerodynamic interactions between turbines. One control strategy to reduce these losses is known as 'wake steering,' in which upstream turbines are yawed to direct wakes away from downstream turbines. Previous wake steering research has assumed perfect information, however, there can be significant uncertainty in many aspects of the problem, including wind inflow and various turbine measurements. Uncertainty has significant implications for performance of wake steering strategies. Consequently, the authors formulate and solve an optimization under uncertainty (OUU) problem for finding optimal wake steering strategies in the presence …