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Articles 78391 - 78420 of 196383
Full-Text Articles in Engineering
Optimization Of Drilling And Blasting Practices At A Western Us Open Pit Copper Mine, Joel Gadikor
Optimization Of Drilling And Blasting Practices At A Western Us Open Pit Copper Mine, Joel Gadikor
Graduate Theses & Non-Theses
The mining process begins with drilling and blasting activities. The efficiency of blasting affects all downstream operations such as loading, hauling, crushing and milling. Therefore drilling and blasting activities should be designed to ensure that designed parameters produce the desired fragmentation. The Kuz-Ram model is a fragmentation prediction model and is widely used for predicting the fragmentation distribution from blasting in the mining industry. This research evaluates the performance of the Kuz-Ram and Modified Kuz-Ram models to determine the most accurate models applicable to a Western US open pit copper mine’s fragmentation data. The performance assessment was done using the …
The Effects Of Underground Blasting On Nearby Pre-Existing Structures, Logan Connolly
The Effects Of Underground Blasting On Nearby Pre-Existing Structures, Logan Connolly
Graduate Theses & Non-Theses
Butte, Montana holds a prestigious place in the history of mining, deemed “The Richest Hill on Earth,” containing a plethora of underground mines. The Orphan Boy/Orphan Girl underground mines, on the western side of Butte, operated from 1895-1956 producing zinc, lead, silver, and manganese. Today, the Orphan Boy mine is part of Montana Tech’s Underground Mine Education Center (UMEC) and the Orphan Girl mine houses the World Museum of Mining. Underground development in the Orphan Boy mine continues to progress as students from Montana Tech receive hands-on underground training; in addition, the UMEC is a multi-disciplinary research facility. Repeated underground …
Evaluating Open Pit Highwall Dig Compliance, Judith Buaba
Evaluating Open Pit Highwall Dig Compliance, Judith Buaba
Graduate Theses & Non-Theses
The mine planning process comprises three major stages: collection of relevant data, application of design methods and measurement of performance. Relevant information about the geology, structure, rock mass and hydrogeology are collected to create a geotechnical model. This information, collected by the geotechnical engineer, is used to design the pit slopes which are incorporated into the pit design by the mine planner based on mining regulations, safety and economics. Drilling, blasting, excavation and dewatering activities mainly constitute the implementation stage of the mine design. Mining to achieve design has proven to be difficult practically. Factors such as geology, blasting and …
Novel Hybrid Perovskite Composites And Microstructures: Synthesis And Characterization, John P. Murphy
Novel Hybrid Perovskite Composites And Microstructures: Synthesis And Characterization, John P. Murphy
Graduate Theses & Non-Theses
The water-energy nexus has been described as one of the great problems of our time. In an ever-growing society the demand for resources such as water and electricity often dictate the magnitude and direction of growth of society. Efficient generation of electricity, with minimal socioeconomic pushback, is paramount in the stable growth of our society. Solar energy harvesting is a strong candidate for the efficient generation of electrical energy with increasingly minimal resource use in fabrication. As manufacturing processes improve and novel materials are discovered/optimized, solar energy harvesting becomes a more economically viable means of energy generation. Hybrid perovskites (HPs) …
Phasor Measurement Unit Testing And Characterization, Joe Perigo
Phasor Measurement Unit Testing And Characterization, Joe Perigo
Graduate Theses & Non-Theses
The power grid is a complex system composed of many different elements. Knowledge of electrical waveform content across the grid is key to managing power and maintaining stability. Electrical waveforms can be represented mathematically as time-varying phasors. Electrical phasors give information pertaining to the magnitude of the waveform as well as the phase relationship of the waveform to a reference. A Phasor Measurement Unit (PMU) is a device that is installed at a node on the power grid and measures electrical phasors. The potential of near real time phasor information is powerful and has driven PMU application technology forward at …
Uav-Based Geotechnical Modeling And Mapping Of An Inaccessible Underground Site, Elizabeth Anne Russell
Uav-Based Geotechnical Modeling And Mapping Of An Inaccessible Underground Site, Elizabeth Anne Russell
Graduate Theses & Non-Theses
Digital photogrammetry is becoming a more common method used for mapping geological and structural rock mass features in underground mining. The issue of capturing geological and structural data in inaccessible, unsupported areas of mines remains even when utilizing terrestrial photogrammetric methods; thus, geotechnical models of mines are left with incomplete datasets. Large unsupported underground voids, like stopes, have the potential to cause major failures, but by filling in the geotechnical data gaps in inaccessible areas, potential failures can be predicted through kinematic analysis of the area’s mapped discontinuities. Implementation of Unmanned Aerial Vehicles (UAVs) in underground mines and recent advances …
High Fidelity Kinetic Model For Flotation: Applications To Rare Earth Elements And Copper/Molybdenum Separations, Richard Ladouceur
High Fidelity Kinetic Model For Flotation: Applications To Rare Earth Elements And Copper/Molybdenum Separations, Richard Ladouceur
Graduate Theses & Non-Theses
A high-fidelity kinetic model was developed to identify and elucidate the effects of varying principle froth flotation parameters on the sub-processes that occur within and between the flotation zones. Whereas traditional models fail to adequately address froth recovery and recovery by entrainment, the high-fidelity model defines these phenomena based on an improved understanding of the pulp/froth interface. Solution chemistry considerations that govern rare earth mineral separation by flotation were identified, characterized, and optimized. Application of novel surfactants such H205 and salicylhydroxamic acid (collectors) and dimethyl glycol monobutyl ether (depressant) was evaluated to define optimal flotation conditions. The effect of pressure …
Investigations Of Solid-State Sintering Behavior Of Binary Refractory Metal Oxide Systems, Maureen Chorney
Investigations Of Solid-State Sintering Behavior Of Binary Refractory Metal Oxide Systems, Maureen Chorney
Graduate Theses & Non-Theses
Refractory metals are commonly alloyed for improved corrosion resistance, thermal stability, and strength. In service, these alloys form highly stable oxides under mildly oxidizing conditions at relatively low temperatures. In order to recycle these materials, high temperature electrochemical processing is required to reduce the refractory metal oxides. To abet experimental evaluation of the electrochemical reduction process under development at the Idaho National Laboratory, binary mixtures of selected refractory metal oxide powders were sintered to produce cathode pellets, which could be suspended in the molten salt electrolyte during reduction experiments. Preparatory literature review revealed a paucity of published information relative to …
Week 4 Lab: Counterlist, Michelle Shu, David Soon, Nyc Tech-In-Residence Corps
Week 4 Lab: Counterlist, Michelle Shu, David Soon, Nyc Tech-In-Residence Corps
Open Educational Resources
Syllabus and materials for the course "CSC 59940: Front-End Web Application Development" delivered at the City College of New York in Spring 2018 by Michelle Shu and David Moon as part of the Tech-in-Residence Corps program.
Autonomous Vehicle, Matyas Gyimesi, Keith Beier, Chris Brunton, Nick Frederick, Aaron Martindale
Autonomous Vehicle, Matyas Gyimesi, Keith Beier, Chris Brunton, Nick Frederick, Aaron Martindale
Research Horizons Day Posters
No abstract provided.
An Evaluation Of Induction Heating In Healthcare Food Industry, Barrett Alexander Hampton
An Evaluation Of Induction Heating In Healthcare Food Industry, Barrett Alexander Hampton
Masters Theses & Specialist Projects
This thesis addresses the problem healthcare facilities are having in maintaining proper food temperatures while transporting meals to patients after food has left the kitchen area. Induction heat has been a known method for generating heat for many years. The commercial food industry currently uses this technology, which is beginning to appear in the residential sector as well because of developments made by manufacturers. This study focuses on the top commercial brand models of induction heaters and the supporting materials currently used to create heat sources to maintain food temperatures in hospitals and long term care facilities.
The research in …
Application Of Huffman Data Compression Algorithm In Hashing Computation, Lakshmi Narasimha Devulapalli Venkata,
Application Of Huffman Data Compression Algorithm In Hashing Computation, Lakshmi Narasimha Devulapalli Venkata,
Masters Theses & Specialist Projects
Cryptography is the art of protecting information by encrypting the original message into an unreadable format. A cryptographic hash function is a hash function which takes an arbitrary length of the text message as input and converts that text into a fixed length of encrypted characters which is infeasible to invert. The values returned by the hash function are called as the message digest or simply hash values. Because of its versatility, hash functions are used in many applications such as message authentication, digital signatures, and password hashing [Thomsen and Knudsen, 2005].
The purpose of this study is to apply …
Failure Analysis Of Philos Plate Construct Used For Pantalar Arthrodesis Paper Ii-Screws And Fem Simulations, Farah Hamandi, Richard T. Laughlin, Tarun Goswami
Failure Analysis Of Philos Plate Construct Used For Pantalar Arthrodesis Paper Ii-Screws And Fem Simulations, Farah Hamandi, Richard T. Laughlin, Tarun Goswami
Biomedical, Industrial & Human Factors Engineering Faculty Publications
A fractured stainless steel 3.5 mm proximal humerus internal locking system (PHILOS) plate and screws were investigated in this paper. This plate was used for ankle arthrodesis of a 68-year-old female with a right ankle deformity. Both the plate and screws were considered in this investigation. Optical and scanning electron microscopes (SEM) were used to document fracture surface characteristics, such as extensive scratching, plastic deformation, rubbed surfaces, discoloration, and pitting, along with cleavage, secondary cracking, deposits of debris, striations, and dimples. Indications of these features show that the plate failed by corrosion fatigue, however, overloading separated the screw(s) in two …
Developing Knowledge Management Strategies, Bryan Gibson, Candice Y. Wallace, Steven Douglas Kreis
Developing Knowledge Management Strategies, Bryan Gibson, Candice Y. Wallace, Steven Douglas Kreis
Kentucky Transportation Center Research Report
Retirements and other staff changes have led to a loss of institutional knowledge across public agencies. These changing workforce dynamics have highlighted the study of knowledge management, and how organizations can best retain their core knowledge bases. Key to understanding knowledge management is how organizations have approached the issue and the most effective methods and processes they have used to retain, store, and disseminate knowledge. Part of the knowledge management discussion includes core competencies, or what basic knowledge and skills are essential to an organization’s mission. Also, considering the impacts of outsourcing on public employment, is another key to understanding …
Thermal And Structural Characterization Of Macro-Encapsulated Phase Change Material Integrated Into Concrete Cubes, Yasir Rashid
Thermal And Structural Characterization Of Macro-Encapsulated Phase Change Material Integrated Into Concrete Cubes, Yasir Rashid
Theses
High-energy consumption in buildings is a research issue of great importance today, with solid-liquid phase change materials (PCMs) proving an excellent candidate for passive means to reduce energy consumption. In the current research, a novel protective coating was developed from geopolymer to encapsulate a PCM to prevent leakage in the liquidous phase. The PCM was characterized using a customized temperature history method (THM) and standard differential scanning calorimetry (DSC). Two different porous materials, polyurethane foam and lightweight expanded clay aggregate (LECA), were selected to hold the PCM and act as a matrix in which to develop PCM capsules. Ingredients of …
Equivalent Capacitance Approach To Calculate Effective Roughness Dielectric Parameters For Copper Foils On Printed Circuit Boards, Marina Y. Koledintseva, Tracey Vincent
Equivalent Capacitance Approach To Calculate Effective Roughness Dielectric Parameters For Copper Foils On Printed Circuit Boards, Marina Y. Koledintseva, Tracey Vincent
Electrical and Computer Engineering Faculty Research & Creative Works
Effective roughness dielectric (ERD) is a homogeneous lossy dielectric layer of certain thickness with effective (averaged) dielectric parameters. The ERD layer is used to model copper foil roughness in printed circuit board interconnects by being placed on a smooth conductor surface to substitute an inhomogeneous transition layer between a conductor and laminate substrate dielectric. This work derives the ERD parameters based on the understanding that there is a gradual variation of concentration of metallic inclusions in the transition layer between the dielectric and foil. The gradual variation can be structured as thin layers that are obtained using the equivalent capacitance …
A Straightforward Updating Criterion For 2-D/3-D Hybrid Discontinuous Galerkin Time-Domain Method Controlling Comparative Error, Wending Mai, Ping Li, C. G. Li, Ming Jiang, Wenqu Hao, Lijun Jiang, Jun Hu
A Straightforward Updating Criterion For 2-D/3-D Hybrid Discontinuous Galerkin Time-Domain Method Controlling Comparative Error, Wending Mai, Ping Li, C. G. Li, Ming Jiang, Wenqu Hao, Lijun Jiang, Jun Hu
Electrical and Computer Engineering Faculty Research & Creative Works
The 2-D/3-D hybrid discontinuous Galerkin time-domain (DGTD) method is efficient to deal with structures that contain elements capable of 2-D simplification. To separate 2-D elements from 3-D ones, a criterion for approximation error manipulation is required. However, in the latest reported technique, this kind of criterion is derived from the causality principle and the Courant-Freidrichs-Lewy constraint, and thus is indirect and inessential to 2-D simplification. As a result, some elements capable of 2-D simplification are unnecessarily flagged as 3-D ones, deteriorating efficiency dramatically. Moreover, controlling absolute error, the traditional criterion is not flexible for structures with complex mode distribution. In …
Direct Error Driven Learning For Deep Neural Networks With Applications To Bigdata, R. Krishnan, Jagannathan Sarangapani, V. A. Samaranayake
Direct Error Driven Learning For Deep Neural Networks With Applications To Bigdata, R. Krishnan, Jagannathan Sarangapani, V. A. Samaranayake
Electrical and Computer Engineering Faculty Research & Creative Works
In this paper, generalization error for traditional learning regimes-based classification is demonstrated to increase in the presence of bigdata challenges such as noise and heterogeneity. To reduce this error while mitigating vanishing gradients, a deep neural network (NN)-based framework with a direct error-driven learning scheme is proposed. To reduce the impact of heterogeneity, an overall cost comprised of the learning error and approximate generalization error is defined where two NNs are utilized to estimate the costs respectively. To mitigate the issue of vanishing gradients, a direct error-driven learning regime is proposed where the error is directly utilized for learning. It …
Displacement And Strain Measurement Up To 1000 °C Using A Hollow Coaxial Cable Fabry-Perot Resonator, Chen Zhu, Yizheng Chen, Yiyang Zhuang, Jie Huang
Displacement And Strain Measurement Up To 1000 °C Using A Hollow Coaxial Cable Fabry-Perot Resonator, Chen Zhu, Yizheng Chen, Yiyang Zhuang, Jie Huang
Electrical and Computer Engineering Faculty Research & Creative Works
We present a hollow coaxial cable Fabry-Perot resonator for displacement and strain measurement up to 1000 °C. By employing a novel homemade hollow coaxial cable made of stainless steel as a sensing platform, the high-temperature tolerance of the sensor is dramatically improved. A Fabry-Perot resonator is implemented on this hollow coaxial cable by introducing two highly-reflective reflectors along the cable. Based on a nested structure design, the external displacement and strain can be directly correlated to the cavity length of the resonator. By tracking the shift of the amplitude reflection spectrum of the microwave resonator, the applied displacement and strain …
Study On The Effect Of Iron-Based Deoxidizing Inhibitors For Coal Spontaneous Combustion Prevention, Chaoyu Hao, Yanling Chen, Jiren Wang, Cunbao Deng, Guang Xu, Fengwei Dai, Rui Si, Hongfei Wang, Haoyu Wang
Study On The Effect Of Iron-Based Deoxidizing Inhibitors For Coal Spontaneous Combustion Prevention, Chaoyu Hao, Yanling Chen, Jiren Wang, Cunbao Deng, Guang Xu, Fengwei Dai, Rui Si, Hongfei Wang, Haoyu Wang
Mining Engineering Faculty Research & Creative Works
To improve the prevention of spontaneous coal combustion, reduced iron powder and other ingredients should be added together to form an iron-based deoxidizing inhibitor, with the dual effect of oxygen consumption and inhibition. The oxygen consumption rate of the inhibitor was studied through experiments. According to the theory of coordination resistance, the coordination resistance of Fe3+ was studied via the density functional method. Subsequently, a comparative experiment of the effects on spontaneous coal combustion was conducted. The research shows that several kinds of common resistance agents that are added to the reduced iron powder can consume oxygen. However, the …
Review Of The Methods For Determination Of Reactive Oxygen Species And Suggestion For Their Application In Advanced Oxidation Induced By Dielectric Barrier Discharges, Emile S. Massima Mouele, Olanrewaju Ojo Fatoba, Omotola Babajide, Kassim O. Badmus, Leslie F. Petrik
Review Of The Methods For Determination Of Reactive Oxygen Species And Suggestion For Their Application In Advanced Oxidation Induced By Dielectric Barrier Discharges, Emile S. Massima Mouele, Olanrewaju Ojo Fatoba, Omotola Babajide, Kassim O. Badmus, Leslie F. Petrik
Mining Engineering Faculty Research & Creative Works
Advanced oxidation processes (AOPs) particularly non-thermal plasmas based on electrical discharges have been widely investigated for water and wastewater treatment. Dielectric barrier discharges (DBDs) generate large amounts of selective and non-selective reactive oxygen species (ROS) such as ozone, hydrogen peroxide, atomic oxygen, superoxide molecular anions and hydroxyl radicals, having been proved to be efficient for water decontamination among various forms of electrical discharge systems. The detection and quantification methods of these oxygen species in non-thermal plasmas have been reviewed. However, their application in dielectric barrier discharge has not been well studied. It is therefore imperative to summarize the various detection …
Development Of A Novel Bioactive Glass Suitable For Osteosarcoma-Related Bone Grafts, Alireza Rahimnejad Yazdi, Lawrence Torkan, Stephen D. Waldman, Mark R. Towler
Development Of A Novel Bioactive Glass Suitable For Osteosarcoma-Related Bone Grafts, Alireza Rahimnejad Yazdi, Lawrence Torkan, Stephen D. Waldman, Mark R. Towler
Chemical and Biochemical Engineering Faculty Research & Creative Works
In this study, zinc borate-based glasses with increasing gallium content (0, 2.5, 5, 10, and 15 wt % Ga) were synthesized and their effect on the viability and proliferation of preosteoblasts and osteosarcoma cancer cells were investigated. Methyl thiazolyl tetrazolium (MTT) cell viability assays using glass degradation extracts revealed that the extracts from glasses with lower Ga contents could enhance the viability of preosteoblasts, while extracts from the glass composition with 15 wt % Ga caused statistically significant reduction of their viability. MTT cell viability assays using the extracts and osteosarcoma cells showed that only extracts from the glass composition …
The Effect Of Incorporating Different Concentrations Of Chlorhexidine Digluconate On The Degree Of Conversion Of An Experimental Adhesive Resin, Lamiaa Mahmoud Moharam, Haidy Nabil Salem, Hanaa Mahmoud Elgamily
The Effect Of Incorporating Different Concentrations Of Chlorhexidine Digluconate On The Degree Of Conversion Of An Experimental Adhesive Resin, Lamiaa Mahmoud Moharam, Haidy Nabil Salem, Hanaa Mahmoud Elgamily
Chemical and Biochemical Engineering Faculty Research & Creative Works
Background: The aim of this study was to evaluate the effect of chlorhexidine digluconate incorporation on the degree of conversion of an experimental adhesive resin. Material and methods: The experimental resin was prepared from 70 wt.% bisphenol A glycerolate dimethacrylate, 30 wt.% hydroxyethyl methacrylate, silanized SiO2 nanofillers, 0.5% of camphorquinone and ethyl 4-dimethylaminebenzoate (binary photo-initiator system). Five chlorhexidine digluconate concentrations (0, 0.5, 1, 2 and 4 wt%) were then incorporated into the experimental resin. Thirty Potassium Bromide pellets were prepared then divided into six groups (n=5/group), representing the tested adhesive resins (Single Bond 2, 0, 0.5, 1, 2 and …
Additive Manufacturing Of Transparent Fused Quartz, Junjie Luo, John M. Hostetler, Luke Gilbert, Jonathan T. Goldstein, Augustine M. Urbas, Douglas A. Bristow, Robert G. Landers, Edward C. Kinzel
Additive Manufacturing Of Transparent Fused Quartz, Junjie Luo, John M. Hostetler, Luke Gilbert, Jonathan T. Goldstein, Augustine M. Urbas, Douglas A. Bristow, Robert G. Landers, Edward C. Kinzel
Mechanical and Aerospace Engineering Faculty Research & Creative Works
This paper investigates a filament-fed process for additive manufacturing (AM) of fused quartz. Glasses such as fused quartz have significant scientific and engineering applications, which include optics, communications, electronics, and hermetic seals. AM has several attractive benefits such as increased design freedom, faster prototyping, and lower processing costs for small production volumes. However, current research into glass AM has focused primarily on nonoptical applications. Fused quartz is studied here because of its desirability for use in high-quality optics due to its high transmissivity and thermal stability. Fused quartz filaments are fed into a CO2 laser-generated molten region, smoothly depositing …
Direct Metal Laser-Sintered Stainless Steel: Comparison Of Microstructure And Hardness Between Different Planes, M. Ghasri-Khouzani, H. Peng, R. Attardo, P. Ostiguy, J. Neidig, R. Billo, D. Hoelzle, M. R. Shankar
Direct Metal Laser-Sintered Stainless Steel: Comparison Of Microstructure And Hardness Between Different Planes, M. Ghasri-Khouzani, H. Peng, R. Attardo, P. Ostiguy, J. Neidig, R. Billo, D. Hoelzle, M. R. Shankar
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Microstructural analysis and micro-hardness measurements were performed on different planes of 316L stainless steel fabricated by direct metal laser sintering (DMLS) technique. A fine cellular network was observed within the steel microstructure, where morphology of most cells changed from columnar on XZ-plane (vertical section) to equiaxed on XY-plane (horizontal section). Correspondingly, morphology of most grains was found to alter from columnar for the XZ-plane to equiaxed in the case of the XY-plane. Moreover, X-ray diffraction (XRD) analysis revealed a fully austenitic structure for both the planes. The average micro-hardness value for the XZ-plane and XY-plane was insignificantly (≈ 3%) different, …
Implementing An Ore Reconciliation System Supported By Statistical Process Control, Bryan Nielson
Implementing An Ore Reconciliation System Supported By Statistical Process Control, Bryan Nielson
Graduate Theses & Non-Theses
There are several stages within mine planning that utilize different block models to help predict future values. Ore reconciliation manages the variance observed between the forecasted values from these block models and actual production data. This paper primarily focuses on an ore reconciliation system that was developed for an open pit copper operation located in the Western United States. A monthly reconciliation approach has been setup in a stepwise format along the mine value chain. Mine call factors are calculated each month for each step within the operation’s mining process to measure the variance between predicted values and production data. …
Optimal Mixed Tracking/Impedance Control With Application To Transfemoral Prostheses With Energy Regeneration, Gholamreza Khademi, Hanieh Mohammadi, Hanz Richter, Daniel J. Simon
Optimal Mixed Tracking/Impedance Control With Application To Transfemoral Prostheses With Energy Regeneration, Gholamreza Khademi, Hanieh Mohammadi, Hanz Richter, Daniel J. Simon
Mechanical Engineering Faculty Publications
We design an optimal passivitybased tracking/impedance control system for a robotic manipulator with energy regenerative electronics, where the manipulator has both actively and semi-actively controlled joints. The semi-active joints are driven by a regenerative actuator that includes an energy-storing element. Method: External forces can have a large influence on energy regeneration characteristics. Impedance control is used to impose a desired relationship between external forces and deviation from reference trajectories. Multi-objective optimization (MOO) is used to obtain optimal impedance parameters and control gains to compromise between the two conflicting objectives of trajectory tracking and energy regeneration. We solve the MOO problem …
Rotordynamic Analysis Of Theoretical Models And Experimental Systems, Cameron R. Naugle
Rotordynamic Analysis Of Theoretical Models And Experimental Systems, Cameron R. Naugle
Master's Theses
This thesis is intended to provide fundamental information for the construction and
analysis of rotordynamic theoretical models, and their comparison the experimental
systems. Finite Element Method (FEM) is used to construct models using Timoshenko
beam elements with viscous and hysteretic internal damping. Eigenvalues
and eigenvectors of state space equations are used to perform stability analysis, produce
critical speed maps, and visualize mode shapes. Frequency domain analysis
of theoretical models is used to provide Bode diagrams and in experimental data
full spectrum cascade plots. Experimental and theoretical model analyses are used
to optimize the control algorithm for an Active Magnetic Bearing …
Modeling And Analysis Of Cal Poly Microgrid, Matthew A. Guevara
Modeling And Analysis Of Cal Poly Microgrid, Matthew A. Guevara
Master's Theses
Microgrids—miniature versions of the electrical grid are becoming increasingly more popular as advancements in technologies, renewable energy mandates, and decreased costs drive communities to adopt them. The modern microgrid has capabilities of generating, distributing, and regulating the flow of electricity, capable of operating in both grid-connected and islanded (disconnected) conditions. This paper utilizes ETAP software in the analysis, simulation, and development of the Cal Poly microgrid. Additionally, an ETAP power system protection tutorial is created to aid students entering the power industry. Microprocessor-based relays are heavily utilized in both the ETAP model and hardware implementation of the system. Case studies …
Near-Optimal Control Of Switched Systems With Continuous-Time Dynamics Using Approximate Dynamic Programming, Tohid Sardarmehni
Near-Optimal Control Of Switched Systems With Continuous-Time Dynamics Using Approximate Dynamic Programming, Tohid Sardarmehni
Mechanical Engineering Research Theses and Dissertations
Optimal control is a control method which provides inputs that minimize a performance index subject to state or input constraints [58]. The existing solutions for finding the exact optimal control solution such as Pontryagin’s minimum principle and dynamic programming suffer from curse of dimensionality in high order dynamical systems. One remedy for this problem is finding near optimal solution instead of the exact optimal solution to avoid curse of dimensionality [31]. A method for finding the approximate optimal solution is through Approximate Dynamic Programming (ADP) methods which are discussed in the subsequent chapters.
In this dissertation, optimal switching in switched …