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Optimization

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Articles 1 - 30 of 727

Full-Text Articles in Engineering

Dynamic Optimization Of High-Altitude Solar Aircraft Trajectories Under Station-Keeping Constraints, Abe Martin, Nathaniel S. Gates, Andrew Ning, John Hedengren Nov 2018

Dynamic Optimization Of High-Altitude Solar Aircraft Trajectories Under Station-Keeping Constraints, Abe Martin, Nathaniel S. Gates, Andrew Ning, John Hedengren

All Student Publications

This paper demonstrates the use of nonlinear dynamic optimization to calculate energy optimal trajectories for a high-altitude, solar-powered Unmanned Aerial Vehicle (UAV). The objective is to maximize the total energy in the system while staying within a 3 km mission radius and meeting other system constraints. Solar energy capture is modeled using the vehicle orientation and solar position, and energy is stored both in batteries and in potential energy through elevation gain. Energy capture is maximized by optimally adjusting the angle of the aircraft surface relative to the sun. The UAV flight and energy system dynamics are optimized over a ...


Swarm Intelligence As An Optimization Technique, Alma Bregaj Nov 2018

Swarm Intelligence As An Optimization Technique, Alma Bregaj

International Journal of Business and Technology

Optimization techniques inspired by swarm intelligence have become increasingly popular during the last years. Swarm intelligence is based on nature-inspired behaviours and is successfully applied to optimisation problems in a variety of fields. The advantage of these approaches over traditional techniques is their robustness and flexibility. These properties make swarm intelligence a successful design paradigm for algorithms that deal with increasingly complex problems. In this paper I am focused on the comparison between different swarmbased optimisation algorithms and I have presented some examples of real practical applications of these algorithms.


Fed-Batch Dynamic Optimization Using Generalized Dual Heuristic Programming, Donald C. Wunsch, M. S. Iyer Oct 2018

Fed-Batch Dynamic Optimization Using Generalized Dual Heuristic Programming, Donald C. Wunsch, M. S. Iyer

Donald C. Wunsch

Traditionally fed-batch biochemical process optimization and control uses complicated theoretical off-line optimizers, with no online model adaptation or re-optimization. This study demonstrates the applicability, effectiveness, and economic potential of a simple phenomenological model for modeling, and an adaptive critic design, generalized dual heuristic programming, for online re-optimization and control of an aerobic fed-batch fermentor. The results are compared with those obtained using a heuristic random optimizer


An Extended Kalman Filter (Ekf) Approach On Fuzzy System Optimization Problem, Nian Zhang, Donald C. Wunsch Oct 2018

An Extended Kalman Filter (Ekf) Approach On Fuzzy System Optimization Problem, Nian Zhang, Donald C. Wunsch

Donald C. Wunsch

Optimizing the membership functions of a fuzzy system can be viewed as a system identification problem for a nonlinear dynamic system. Basically, we can view the optimization of fuzzy membership functions as a weighted least-squares minimization problem, where the error vector is the difference between the fuzzy system outputs and the target values for those outputs. The extended Kalman filter algorithm is a good choice to solve this system identification problem, not only because it is a derivative-based algorithm that is suitable to solve the weighted least-squares minimization problem, but also because of its appealing predictor-corrector feature for nonlinear system ...


Adaptive Critic Designs, Danil V. Prokhorov, Donald C. Wunsch Oct 2018

Adaptive Critic Designs, Danil V. Prokhorov, Donald C. Wunsch

Donald C. Wunsch

We discuss a variety of adaptive critic designs (ACDs) for neurocontrol. These are suitable for learning in noisy, nonlinear, and nonstationary environments. They have common roots as generalizations of dynamic programming for neural reinforcement learning approaches. Our discussion of these origins leads to an explanation of three design families: heuristic dynamic programming, dual heuristic programming, and globalized dual heuristic programming (GDHP). The main emphasis is on DHP and GDHP as advanced ACDs. We suggest two new modifications of the original GDHP design that are currently the only working implementations of GDHP. They promise to be useful for many engineering applications ...


A Memetic Algorithm Configured Via A Problem Solving Environment For The Hamiltonian Cycle Problems, X. S. Chen, Meng-Hiot Lim, Donald C. Wunsch Oct 2018

A Memetic Algorithm Configured Via A Problem Solving Environment For The Hamiltonian Cycle Problems, X. S. Chen, Meng-Hiot Lim, Donald C. Wunsch

Donald C. Wunsch

Algorithm Development Environment for Permutation-based problems (ADEP) is a software environment for configuring meta-heuristics for solving combinatorial optimization problems. This paper describes the key features of ADEP and how the environment was used to generate a Memetic Algorithm (MA) solution for Hamiltonian Cycle Problems (HCP). The effectiveness of the MA algorithm is demonstrated through computer simulations and its performance is compared with backtracking and other heuristic techniques such as Simulated Annealing, Tabu Search, and Ant Colony Optimization.


A Simple, Robust, And On-Site Microwave Technique For Determining Water-To-Cement Ratio (W/C) Of Fresh Portland Cement-Based Materials, K. Mubarak, Karl Joseph Bois, R. Zoughi Sep 2018

A Simple, Robust, And On-Site Microwave Technique For Determining Water-To-Cement Ratio (W/C) Of Fresh Portland Cement-Based Materials, K. Mubarak, Karl Joseph Bois, R. Zoughi

Reza Zoughi

Inspection and evaluation of cement-based materials such as concrete is of great interest to the construction industry. In particular, real-time and on-site evaluation of water-to-cement ratio (w/c) is an important practical issue, since the compressive strength of a concrete structure is significantly influenced by its w/c. Currently, there is no single real-time, on-site, relatively in-expensive, easy-to-implement, and operator friendly technique for evaluating this parameter. Microwave nondestructive testing and evaluation techniques have shown great promise when used for inspection and evaluation of the properties of cement-based materials. In this paper, the optimal design of a monopole antenna probe used ...


Operational Squadron Scheduling, Khaled A. Almannaei Sep 2018

Operational Squadron Scheduling, Khaled A. Almannaei

Theses and Dissertations

The 28th Operational Weather Squadron (28th OWS) is responsible for producing and disseminating mission planning and execution weather analyses and forecasts. The squadron must prepare schedules that meet the needs of their mission while dealing with real-world constraints such as time windows, task priorities, and intermittent recurring missions. The 28th OWS's manning consists of active duty, deployed in-place, reserve, civilian and contract personnel. In this research, a scheduling model and algorithm are provided as an approach to crew scheduling for the 28th Operational Weather Squadron. Scheduling in the 28th OWS is complex and can be time consuming. This model ...


Design Of Wind Turbine Tower Height And Blade Length: An Optimization Approach, Ryan Wass Sep 2018

Design Of Wind Turbine Tower Height And Blade Length: An Optimization Approach, Ryan Wass

Mechanical Engineering Undergraduate Honors Theses

The wind industry is a fast growing market and is quickly becoming competitive with traditional non-renewable energy resources. As with any developing industry, research must continually be redefined as more complex understandings of design variables are learned. Optimization studies are common ways to quickly refine design variable selections. Historical wind turbine data shows that the tower hub height to rotor diameter ratio scales almost linearly. However there is no specific rule that dictates the optimum hub height for a given diameter. This study addresses this question by using an Excel based optimization program to determine the height to diameter ratio ...


Robust Allocation Of Funds For Nonstructural Flood Risk Mitigation In Coastal Louisiana, Simón Gómez Sierra, David R. Johnson, Matthew P. Shisler, Zachariah T. Richardson Aug 2018

Robust Allocation Of Funds For Nonstructural Flood Risk Mitigation In Coastal Louisiana, Simón Gómez Sierra, David R. Johnson, Matthew P. Shisler, Zachariah T. Richardson

The Summer Undergraduate Research Fellowship (SURF) Symposium

Coastal Louisiana is a critical economic, ecological and cultural asset, acting as a major hub for waterborne commerce, fisheries, and the petrochemical industry, and also as one of the world’s unique wetlands. Unfortunately, this rich environment is in great danger from the threat of hurricanes and storm surge flooding. Direct economic losses are estimated to average $2.7 billion per year under current conditions, and this could increase to $12 billion a year, or more, within 50 years if nothing is done. To prevent this catastrophe, Louisiana has developed a Comprehensive Master Plan for a Sustainable Coast, which plans ...


Developing Optimization Techniques For Logistical Tendering Using Reverse Combinatorial Auctions, Jennifer Kiser Aug 2018

Developing Optimization Techniques For Logistical Tendering Using Reverse Combinatorial Auctions, Jennifer Kiser

Electronic Theses and Dissertations

In business-to-business logistical sourcing events, companies regularly use a bidding process known as tendering in the procurement of transportation services from third-party providers. Usually in the form of an auction involving a single buyer and one or more sellers, the buyer must make decisions regarding with which suppliers to partner and how to distribute the transportation lanes and volume among its suppliers; this is equivalent to solving the optimization problem commonly referred to as the Winner Determination Problem. In order to take into account the complexities inherent to the procurement problem, such as considering a supplier’s network, economies of ...


Optimization Methods For Maintaining Complex Systems, Khatereh Ahadi Aug 2018

Optimization Methods For Maintaining Complex Systems, Khatereh Ahadi

Theses and Dissertations

My dissertation research focuses on developing and applying methodologies for optimizing the maintenance of complex systems. The main goal of these methodologies is minimizing maintenance and failure cost and maximizing the economic output of the systems. In Chapter 1, we develop a stochastic programming model to select a budget-limited subset of maintenance dredging projects to maximize the expected commodity tonnage that can be transported through the inland waterway system. The inland navigation system ensures cost-effective marine transportation throughout many portions of the country and is therefore vital to the U.S. economy. The uncertainty in these processes creates a challenging ...


Efficient Incorporation Of Fatigue Damage Constraints In Wind Turbine Blade Optimization, Bryce Taylor Ingersoll Aug 2018

Efficient Incorporation Of Fatigue Damage Constraints In Wind Turbine Blade Optimization, Bryce Taylor Ingersoll

All Theses and Dissertations

Improving the wind turbine blade design has a significant effect on the efficiency of the wind turbine. This is a challenging multi-disciplinary optimization problem. During the blade design process, the aerodynamic shapes, sizing of the structural members, and material composition must all be determined and optimized. Some previous blade design methods incorporate the wind turbine's static response with an added safety factor to account for neglected dynamic effects. Others incorporate the dynamic response, but in general is limited to a few design cases. By not fully incorporating the dynamic response of the wind turbine, the final turbine ...


Chaotic Phase-Coded Waveforms With Space-Time Complementary Coding For Mimo Radar Applications, Sheng Hong, Fuhui Zhou, Yantao Dong, Zhixin Zhao, Yuhao Wang, Maosong Yan Jul 2018

Chaotic Phase-Coded Waveforms With Space-Time Complementary Coding For Mimo Radar Applications, Sheng Hong, Fuhui Zhou, Yantao Dong, Zhixin Zhao, Yuhao Wang, Maosong Yan

Electrical and Computer Engineering Faculty Publications

A framework for designing orthogonal chaotic phase-coded waveforms with space-time complementary coding (STCC) is proposed for multiple-input multiple-output (MIMO) radar applications. The phase-coded waveform set to be transmitted is generated with an arbitrary family size and an arbitrary code length by using chaotic sequences. Due to the properties of chaos, this chaotic waveform set has many advantages in performance, such as anti-interference and low probability of intercept. However, it cannot be directly exploited due to the high range sidelobes, mutual interferences, and Doppler intolerance. In order to widely implement it in practice, we optimize the chaotic phase-coded waveform set from ...


Sequence-Based Simulation-Optimization Framework With Application To Port Operations At Multimodal Container Terminals, Mariam Aladdin Kotachi Jul 2018

Sequence-Based Simulation-Optimization Framework With Application To Port Operations At Multimodal Container Terminals, Mariam Aladdin Kotachi

Engineering Management & Systems Engineering Theses & Dissertations

It is evident in previous works that operations research and mathematical algorithms can provide optimal or near-optimal solutions, whereas simulation models can aid in predicting and studying the behavior of systems over time and monitor performance under stochastic and uncertain circumstances. Given the intensive computational effort that simulation optimization methods impose, especially for large and complex systems like container terminals, a favorable approach is to reduce the search space to decrease the amount of computation.

A maritime port can consist of multiple terminals with specific functionalities and specialized equipment. A container terminal is one of several facilities in a port ...


Process Improvement At "The Manse On Marsh", Kevin C. Manko Jun 2018

Process Improvement At "The Manse On Marsh", Kevin C. Manko

Industrial and Manufacturing Engineering

The Manse on Marsh is an independent and assisted living facility that prides itself on providing life-enriching care for the elderly. Considering that the staff is essential to supply this care and turnover rates are a constant factor, the company would like to reduce the time it takes to hire new employees by at least one week. To facilitate this goal, process flow maps are utilized to assess the current state of the hiring process and metrics are applied to support future state design decisions. After performing a value added analysis and identifying areas of waste, a total of 20 ...


Healing Alternatives Workspace Remodel, Lissandra Ilcyn, Jenifer Astrid Colmenares, Grace E. Kuffner Jun 2018

Healing Alternatives Workspace Remodel, Lissandra Ilcyn, Jenifer Astrid Colmenares, Grace E. Kuffner

Industrial and Manufacturing Engineering

Healing Alternatives is an acupuncture office space located in a repurposed house in San Luis Obispo. Healing Alternatives’ current facility layout does not allow for an additional treatment room or the space to provide additional services because of the wasted space within the facility. Furthermore, patients can be disrupted by noise outside the treatment room causing a negative customer experience. The project team’s objectives are to:

o Design two layout alternatives

o Provide a time estimate for each alternative

o Provide a cost analysis of each alternative

o Implement 5s methodology on the storage room

o Provide a 2D-3D ...


Vial Of Life Redesign, Andrew Scott Heim, Marisonn Manalo Jun 2018

Vial Of Life Redesign, Andrew Scott Heim, Marisonn Manalo

Industrial and Manufacturing Engineering

Cambria Anonymous Neighbors (CAN), a nonprofit organization assisting the residences of Cambria, hopes to standardize first responder procedures and make medical information easily accessible in case of a medical emergency. Currently the container costs $3.78. CAN would like to provide 2000 containers at a lower cost. After researching materials, acrylic was found to be the best option for the container material due to its low cost and durability. A laser cutter was used to cut the acrylic pieces, and then a set of step by step instructions were created to assemble the product. To reduce the cost of acrylic ...


From Geographically Dispersed Data Centers Towards Hierarchical Edge Computing, Abbas Kiani May 2018

From Geographically Dispersed Data Centers Towards Hierarchical Edge Computing, Abbas Kiani

Dissertations

No abstract provided.


Modeling Of Capacitor Impedance In Switching Converters, Jonathan W. Kimball, Philip T. Krein, Kevin R. Cahill May 2018

Modeling Of Capacitor Impedance In Switching Converters, Jonathan W. Kimball, Philip T. Krein, Kevin R. Cahill

Jonathan W. Kimball

Switched capacitor (SC) converters are gaining acceptance as alternatives to traditional, inductor-based switching power converters. Proper design of SC converters requires an understanding of all loss sources and their impacts on circuit operation. In the present work, an equivalent resistance method is developed for analysis, and equivalent resistance formulae are presented for various modes of operation. Quasiresonant converters are explored and compared to standard SC converters. Comparisons to inductor-based switching power converters are made. A number of capacitor technologies are evaluated and compared for applications to both SC converters and inductor-based converters. The resulting model can be used to accurately ...


Dynamic Maximum Power Point Tracking Of Photovoltaic Arrays Using Ripple Correlation Control, Trishan Esram, Jonathan W. Kimball, Philip T. Krein, Patrick L. Chapman, Pallab Midya May 2018

Dynamic Maximum Power Point Tracking Of Photovoltaic Arrays Using Ripple Correlation Control, Trishan Esram, Jonathan W. Kimball, Philip T. Krein, Patrick L. Chapman, Pallab Midya

Jonathan W. Kimball

A dynamically rapid method used for tracking the maximum power point of photovoltaic arrays, known as ripple correlation control, is presented and verified against experiment. The technique takes advantage of the signal ripple, which is automatically present in power converters. The ripple is interpreted as a perturbation from which a gradient ascent optimization can be realized. The technique converges asymptotically at maximum speed to the maximum power point without the benefit of any array parameters or measurements. The technique has simple circuit implementations.


Discrete-Time Ripple Correlation Control For Maximum Power Point Tracking, Jonathan W. Kimball, Philip T. Krein May 2018

Discrete-Time Ripple Correlation Control For Maximum Power Point Tracking, Jonathan W. Kimball, Philip T. Krein

Jonathan W. Kimball

Ripple correlation control (RCC) is a high-performance real-time optimization technique that has been applied to photovoltaic maximum power point tracking. This paper extends the previous analog technique to the digital domain. The proposed digital implementation is less expensive, more flexible, and more robust. with a few simplifications, the RCC method is reduced to a sampling problem; that is, if the appropriate variables are sampled at the correct times, the discrete-time RCC (DRCC) algorithm can quickly find the optimal operating point. First, the general DRCC method is derived and stability is proven. Then, DRCC is applied to the photovoltaic maximum power ...


Control Strategy Optimization For A Parallel Hybrid Electric Vehicle, Andrew Meintz, Mehdi Ferdowsi May 2018

Control Strategy Optimization For A Parallel Hybrid Electric Vehicle, Andrew Meintz, Mehdi Ferdowsi

Mehdi Ferdowsi

The efficiency improvement of parallel hybrid electric vehicles (HEVs) is strongly dependent on how the supervisory control of a vehicle determines the power split between the internal combustion engine (ICE) and the electric motor of the vehicle. This paper presents a classification of current supervisory control techniques with distinction between dynamic and static control methods; a description of the simulation software ADvanced Vehicle SimulatOR (ADVISOR) with Matlab Simulink for simulation of a rule-based control strategy, and proposed optimization methods.


Standby Leakage Power Reduction Technique For Nanoscale Cmos Vlsi Systems, Heungjun Jeon, Yong-Bin Kim, Minsu Choi May 2018

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

Minsu Choi

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 (ISUB) and the band-to-band tunneling (BTBT) current (IBTBT). 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 ...


Cost-Driven Optimization Of Fault Coverage In Combined Built-In Self-Test/Automated Test Equipment Testing, Shanrui Zhang, Minsu Choi, Nohpill Park, Fabrizio Lombardi May 2018

Cost-Driven Optimization Of Fault Coverage In Combined Built-In Self-Test/Automated Test Equipment Testing, Shanrui Zhang, Minsu Choi, Nohpill Park, Fabrizio Lombardi

Minsu Choi

As the design and fabrication complexities for the instrumentation-on-silicon systems intensify, optimization of combined Built-In Self-Test (BIST) and Automated Test Equipment (ATE) testing becomes more desirable to meet the required fault-coverage while maintaining acceptable cost overhead. The cost associated with combined BIST/ATE testing of such systems mainly consists of the following; (1) the cost induced by the BIST area overhead and (2) the cost induced by the overall testing time. In general, BIST has faster testing speed than ATE, while it can provide only limited fault-coverage and driving higher fault-coverage from BIST means additional area cost overhead. On the ...


Development Of Optimal Material Extrusion Additive Manufacturing Tool Path Parameters For Minimizing Void Regions Using Contemporary Tool Path Solutions, Hasti Eiliat May 2018

Development Of Optimal Material Extrusion Additive Manufacturing Tool Path Parameters For Minimizing Void Regions Using Contemporary Tool Path Solutions, Hasti Eiliat

Electronic Theses and Dissertations

A problem with the planning solutions for the additive manufacturing material extrusion process is a lack of optimization strategies to improve upon the standard raster and contour toolpaths. After experimental testing, it was recognized that a component’s strength relationship with respect to the volume of material usage is inconsistent and that failures occurred in regions of voids. From previous studies, it was found that a build orientation in the material extrusion process influences the support material requirements, processing time, surface finish, voids volume, etc. This dissertation aims to identify, minimize, and manage void regions during the toolpath generation, and ...


Assessment And Optimization Of Environmental Systems Using Data Analysis And Simulation., Milad Ebrahimi May 2018

Assessment And Optimization Of Environmental Systems Using Data Analysis And Simulation., Milad Ebrahimi

Electronic Theses and Dissertations

For most environmental systems, specifically wastewater treatment plants and aquifers, a significant number of performance data variables are attained on a time series basis. Due to the interconnectedness of the variables, it is often difficult to assess over-arching trends and quantify temporal operational performance. The objective of this research study was to provide an effective means for comprehensive temporal evaluation of environmental systems. The proposed methodology used several multivariate data analyses and statistical techniques to present an assessment framework for the water quality monitoring programs as well as optimization of treatment plants and aquifer systems. The developed procedure considered the ...


Evaluating The Practices Of A Small Business: A Case Study, Madeleine Bernadicou May 2018

Evaluating The Practices Of A Small Business: A Case Study, Madeleine Bernadicou

Construction Management

Companies are in constant search to increase profits. The company success is dependent on its standard operational procedures, otherwise known as SOP. Golden State Irrigation and Noack Pump is a non-union merit shop contractor that performs irrigation work in the California’s central valley. This paper researches the utilized methods of the company to see if it is operating at an optimal level. The methodology used in this project is a case study, where multiple jobs, income statements, and cash flows were analyzed, along with conducted interviews. Both qualitative and quantitative data were collected in the investigation of this case ...


Optimizing The Distributed Hydrology Soil Vegetation Model For Uncertainty Assessment With Serial, Multicore And Distributed Accelerations, Andrew Adriance May 2018

Optimizing The Distributed Hydrology Soil Vegetation Model For Uncertainty Assessment With Serial, Multicore And Distributed Accelerations, Andrew Adriance

Master's Theses and Project Reports

Hydrology is the study of water. Hydrology tracks various attributes of water such as its quality and movement. As a tool Hydrology allows researchers to investigate topics such as the impacts of wildfires, logging, and commercial development. With perfect and complete data collection researchers could answer these questions with complete certainty. However, due to cost and potential sources of error this is impractical. As such researchers rely on simulations.

The Distributed Hydrology Soil Vegetation Model(also referenced to as DHSVM) is a scientific mathematical model to numerically represent watersheds. Hydrology, as with all fields, continues to produce large amounts of ...


Methods For The Aerostructural Design And Optimization Of Wings With Arbitrary Planform And Payload Distribution, Jeffrey D. Taylor May 2018

Methods For The Aerostructural Design And Optimization Of Wings With Arbitrary Planform And Payload Distribution, Jeffrey D. Taylor

All Graduate Theses and Dissertations

The design of an aircraft wing often involves the use of mathematical methods for simultaneous aerodynamic and structural design. The goal of many of these methods is to minimize the drag on the wing. A variety of computer models exist for this purpose, but some require the use of expensive time and computational resources to give meaningful results. As an alternative, some mathematical methods have been developed that give reason ably accurate results without the need for a computer. However, most of these methods can only be used for wings with specific shapes and payload distributions. In this thesis, a ...