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Articles 58741 - 58770 of 198044

Full-Text Articles in Engineering

Design Of Prototype Prosthesis For A Canine With A Right Front Limb Deformity As An Alternate Approach To Stabilize Gait And Withstand Gait Forces, Tayler R. Kastlunger Jun 2020

Design Of Prototype Prosthesis For A Canine With A Right Front Limb Deformity As An Alternate Approach To Stabilize Gait And Withstand Gait Forces, Tayler R. Kastlunger

Master's Theses

Congenital and developmental limb deformities in canines are rare and can occur as a genetic disorder or be caused by extrinsic factors. Without surgery to correct the deformity, conservative management can be implemented to manage exercise and restrict high-intensity activity of the canine. However, any alteration to the normal gait and locomotive biomechanics of a canine can have significant long-term effects on the musculoskeletal health and quality of life of the canine. To improve quality of life and provide an alternative and more cost-effective approach to surgery, a custom prosthetic was designed and developed for a canine born with a …


Investigation Of New Forward Osmosis Draw Agents And Prioritization Of Recent Developments Of Draw Agents Using Multi-Criteria Decision Analysis, Jodie Wei Yu Jun 2020

Investigation Of New Forward Osmosis Draw Agents And Prioritization Of Recent Developments Of Draw Agents Using Multi-Criteria Decision Analysis, Jodie Wei Yu

Master's Theses

Forward osmosis (FO) is an emerging technology for water treatment due to their ability to draw freshwater using an osmotic pressure gradient across a semi-permeable membrane. However, the lack of draw agents that could both produce reasonable flux and be separated from the draw solution at a low cost stand in the way of widespread implementation. This study had two objectives: evaluate the performance of three materials — peptone, carboxymethyl cellulose (CMC), and magnetite nanoparticles (Fe3O4 NPs) — as potential draw agents, and to use multi-criteria decision matrices to systematically prioritize known draw agents from literature for …


A Study Of The Utilization Of Panel Method For Low Aspect Ratio Wing Analysis, William Barton D. Newey Jun 2020

A Study Of The Utilization Of Panel Method For Low Aspect Ratio Wing Analysis, William Barton D. Newey

Master's Theses

This study demonstrates the applicability of using a modified application strategy of panel method to analyze low aspect ratio wings at preliminary design phases. Conventional panel methods fail to capture the leading edge vortex (LEV) that is shed by wings with low aspect ratios, typically below 2 depending on planform. This aerodynamic phenomenon contributes to a significant amount of the lift of these wings and the result is a drastic underestimation of the lift characteristics when analyzed by conventional panel method. To capture the effect of the leading edge vortex, a panel method code was used with an extended definition …


A Comparative Study On Seismic Analysis Methods And The Response Of Systems With Classical And Nonclassical Damping, Noah G. Bleichner Jun 2020

A Comparative Study On Seismic Analysis Methods And The Response Of Systems With Classical And Nonclassical Damping, Noah G. Bleichner

Master's Theses

This thesis investigated the application of seismic analysis methods and the response of idealized shear frames subjected to seismic loading. To complete this research, a Design Basis Earthquake (DBE) for a project site in San Luis Obispo, CA, and five past earthquake records were considered. The DBE was produced per the American Society of Civil Engineers’ Minimum Design Loads for Buildings and Other Structures (ASCE 7-10) and used for application of the Equivalent Lateral Force Procedure (ELFP) and Response Spectrum Analysis (RSA). When applying RSA, the modal peak responses were combined using the Absolute Sum (ABS), Square-Root-of-the-Sum-of-Squares (SRSS), and Complete …


Three Axis Attitude Control System Design And Analysis Tool Development For The Cal Poly Cubesat Laboratory, Liam T. Bruno Jun 2020

Three Axis Attitude Control System Design And Analysis Tool Development For The Cal Poly Cubesat Laboratory, Liam T. Bruno

Master's Theses

The Cal Poly CubeSat Laboratory (CPCL) is currently facing unprecedented engineering challenges—both technically and programmatically—due to the increasing cost and complexity of CubeSat flight missions. In responding to recent RFPs, the CPCL has been forced to find commercially available solutions to entire mission critical spacecraft subsystems such as propulsion and attitude determination & control, because currently no in-house options exist for consideration. The commercially available solutions for these subsystems are often extremely expensive and sometimes provide excessively good performance with respect to mission requirements. Furthermore, use of entire commercial subsystems detracts from the hands-on learning objectives of the CPCL by …


Wildland Fire Location Management System (Wflms), Robert G. Goldie, Jack A. Gallegos Jun 2020

Wildland Fire Location Management System (Wflms), Robert G. Goldie, Jack A. Gallegos

Electrical Engineering

Wildland firefighters work in complex, dangerous environments where effective communication is key to developing situational awareness. Currently, the only communication firefighters have is with Very High Frequency (VHF) 160 MHz band analog radios. While digital radio protocols could potentially allow location data and commands to be sent to field crews, the technology is primarily for voice communication. This project presents a new system that frees up voice channels and uses LoRa transceivers for robust communication. The system allows for emergency and location reports to be sent to a dispatcher via an airborne repeater. The entire system is software-defined, so it …


Curriculum Development For Robotics Technology Program, Sanjeevi Chitikeshi, Shirshak K. Dhali, Betsey Odell, Vukica Jovanovic, Cheng Y. Lin Jun 2020

Curriculum Development For Robotics Technology Program, Sanjeevi Chitikeshi, Shirshak K. Dhali, Betsey Odell, Vukica Jovanovic, Cheng Y. Lin

Engineering Technology Faculty Publications

With a growing need for a more skilled workforce, providing industry-driven and employment centric training services is an important national priority. Over 3.4 million manufacturing jobs will need to be filled across the United Sates over the next decade. The skills gap is becoming greater based on the statistics provided by the Global Robotics Technology Market: Forecast, 2014-2020 published by Research and Markets, reporting that the worldwide robotics market is forecast to grow from the 2015 level of $26.98B to $82.78B in 2020. This 11 % compounded average growth in the next five years is unprecedented. Given the anticipated growth …


Design A Class Infusion Project Of Asme Geometric Dimensioning And Tolerancing Standard, Cheng Y. Lin, Hamid Eisazadeh, Alok K. Verma Jun 2020

Design A Class Infusion Project Of Asme Geometric Dimensioning And Tolerancing Standard, Cheng Y. Lin, Hamid Eisazadeh, Alok K. Verma

Engineering Technology Faculty Publications

This paper describes the development of a short course of Geometric Dimensioning and tolerancing (GD&T) for Mechanical Engineering (ME)/Mechanical Engineering Technology (MET) students in their freshman/sophomore classes. This class-infusion project was assisted and validated by an ASME Standards and Certification Engineer and was jointly sponsored by the ASME Committee on Engineering Education and the ASME Council on Standards and Certification. To assess the performance of the project, an instrument was developed with multiple-choice problems and survey questions for the students. The results of a field test in a sophomore manufacturing class are presented. The module is available at the ASME …


Soil Fatigue Hazard Screening Analyses Framework For Spacio-Temporally Clustered Induced Seismicity With Examples Of Damage Potential Due To Liquefaction, Merissa L. Zuzulock, Oliver Denzil S. Taylor, Norbert H. Maerz Jun 2020

Soil Fatigue Hazard Screening Analyses Framework For Spacio-Temporally Clustered Induced Seismicity With Examples Of Damage Potential Due To Liquefaction, Merissa L. Zuzulock, Oliver Denzil S. Taylor, Norbert H. Maerz

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Current studies that focus solely on the cause of the increase in seismicity neglect to include considerations for effects of small magnitude cluster events on federal infrastructure. These effects can be almost undetectable at first, but if left unchecked can evolve into a larger issue. The need to reassess and potentially modify the established risk assessment practices for evaluations of federal infrastructure needs to be reviewed to ensure the continued ability of the structure to function as intended. The U.S. Army Corps of Engineers (USACE) is responsible for hydroelectric power, flood protection, recreational areas, navigational channels and water supply along …


Me-Em Enewsbrief, June 2020, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University Jun 2020

Me-Em Enewsbrief, June 2020, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.


Deep Learning Methods For Efficient Image Coding, Zachary Daniel Bellay Jun 2020

Deep Learning Methods For Efficient Image Coding, Zachary Daniel Bellay

Computer Science and Engineering Master's Theses

Video data makes up 58% of all internet traffic and is growing as self-driving car cameras, 4K televisions, and video surveillance systems continue to come online. Traditional heuristics based image and video codecs such as JPEG and HEVC have been successful thus far, however, these approaches lack the ability to leverage big data to gain massive insights. Six deep learning based approaches are proposed to tackle efficient image/video compression and image compression for machine classification.


Designing Metal-Organic Frameworks For Natural Gas Storage And Delivery, Labeeb Mohammed Ali Jun 2020

Designing Metal-Organic Frameworks For Natural Gas Storage And Delivery, Labeeb Mohammed Ali

Chemical and Petroleum Engineering Theses

Natural gas is major resource in UAE, constitute about 90% methane and as compared to other fossil fuels, it is more environmentally friendly. Energy demand from natural gas can be projected to exceed two hundred exajoules per year in 2040. In the UAE, many natural gas filling stations are already built for utilizing natural gas as a vehicle transportation fuel where these materials have potential applications to store and deliver this fuel. This research aims to study various kinds of Metal-Organic Frameworks, and to investigate adsorption properties for the storage of natural gas and its delivery. MOFs possess porous material …


Monte Carlo Tree Search Applied To A Modified Pursuit/Evasion Scotland Yard Game With Rendezvous Spaceflight Operation Applications, Joshua A. Daughtery Jun 2020

Monte Carlo Tree Search Applied To A Modified Pursuit/Evasion Scotland Yard Game With Rendezvous Spaceflight Operation Applications, Joshua A. Daughtery

Theses and Dissertations

This thesis takes the Scotland Yard board game and modifies its rules to mimic important aspects of space in order to facilitate the creation of artificial intelligence for space asset pursuit/evasion scenarios. Space has become a physical warfighting domain. To combat threats, an understanding of the tactics, techniques, and procedures must be captured and studied. Games and simulations are effective tools to capture data lacking historical context. Artificial intelligence and machine learning models can use simulations to develop proper defensive and offensive tactics, techniques, and procedures capable of protecting systems against potential threats. Monte Carlo Tree Search is a bandit-based …


Semi-Lagrangian Implicit Bhatnagar-Gross-Krook Collision Model For The Finite-Volume Discrete Boltzmann Method, Leitao Chen, Sauro Succi, Xiaofeng Cai, Laura Schaefer Jun 2020

Semi-Lagrangian Implicit Bhatnagar-Gross-Krook Collision Model For The Finite-Volume Discrete Boltzmann Method, Leitao Chen, Sauro Succi, Xiaofeng Cai, Laura Schaefer

Publications

In order to increase the accuracy of temporal solutions, reduce the computational cost of time marching, and improve the stability associated with collisions for the finite-volume discrete Boltzmann method, an advanced implicit Bhatnagar-Gross-Krook (BGK) collision model using a semi-Lagrangian approach is proposed in this paper. Unlike existing models, in which the implicit BGK collision is resolved either by a temporal extrapolation or by a variable transformation, the proposed model removes the implicitness by tracing the particle distribution functions (PDFs) back in time along their characteristic paths during the collision process. An interpolation scheme is needed to evaluate the PDFs at …


Application Of Mounting Personal Pid Voc Sensors To Small Unmanned Aircraft Systems To Aid First Responders, Cheri Marcham Jun 2020

Application Of Mounting Personal Pid Voc Sensors To Small Unmanned Aircraft Systems To Aid First Responders, Cheri Marcham

Publications

Small Unmanned Aerial Systems in Emergency Response

  • Current sUAS Uses
    • Search and rescue
    • Thermal imaging
    • Evaluating structural stability
    • Spread of wildfires
    • Storm damage


Design And Test Of An Autonomy Monitoring Service To Detect Divergent Behaviors On Unmanned Aerial Systems, Loay Y. Almannaei Jun 2020

Design And Test Of An Autonomy Monitoring Service To Detect Divergent Behaviors On Unmanned Aerial Systems, Loay Y. Almannaei

Theses and Dissertations

Operation of Unmanned Aerial Vehicles (UAV) support many critical missions in the United State Air Force (USAF). Monitoring abnormal behavior is one of many responsibilities of the operator during a mission. Some behaviors are hard to be detect by an operator, especially when flying one or more autonomous vehicles; as such, detections require a high level of attention and focus to flight parameters. In this research, a monitoring system and its algorithm are designed and tested for a target fixed-wing UAV. The Autonomy Monitoring Service (AMS) compares the real vehicle or simulated Vehicle with a similar simulated vehicle using Software …


An Analysis Of A Hurricane Loss Model, Validation From Tyndall Afb, And Applications For The Air Force, Nestor Hernandez Jun 2020

An Analysis Of A Hurricane Loss Model, Validation From Tyndall Afb, And Applications For The Air Force, Nestor Hernandez

Theses and Dissertations

Recent reconstruction of infrastructure and its associated cost due to hurricanes justify research into hurricane loss models that can provide a more robust cost estimate. Academic research indicates that hurricane disasters are becoming more frequent and are becoming costlier. This research intends to explore hurricane loss models used by Federal Emergency Management Agency (FEMA), Risk Management Solution (RMS) and Florida State University (FSU). Within the literature review, key components of hurricane loss models were identified. These models and the key components were explored in order to help bring an understanding of loss estimation. The research found that the implementation of …


Tension-Tension Fatigue Behavior Of Nextel™ 720/Alumina-Mullite Ceramic Composite At 1200°C In Air And In Steam, Sarah A. Witzgall Jun 2020

Tension-Tension Fatigue Behavior Of Nextel™ 720/Alumina-Mullite Ceramic Composite At 1200°C In Air And In Steam, Sarah A. Witzgall

Theses and Dissertations

Uniaxial tension-tension fatigue performance of an oxide-oxide continuous fiber ceramic composite was studied at 1200°C in laboratory air and in steam. The composite is reinforced with laminated, 0/90 mullite/alumina (NEXTEL™720) fibers woven in an eight-harness satin weave and has a porous alumina/mullite matrix. There is no interphase between the fiber and matrix. The composite relies on the porous matrix for crack deflection and flaw tolerance. Tension-tension fatigue was examined for maximum stresses of 45 – 136 MPa in air and in steam. To assess the effects of the steam environment on fatigue performance, experimental results obtained in air are compared …


Multi-Robots Global Path Planning Based On Pso Algorithm And Cubic Spline, Qiang Ning, Gao Jie, Fengju Kang Jun 2020

Multi-Robots Global Path Planning Based On Pso Algorithm And Cubic Spline, Qiang Ning, Gao Jie, Fengju Kang

Journal of System Simulation

Abstract: There are shortcomings such as premature convergence, high encoding dimension and unsmooth path for particle swarm optimization (PSO) algorithm to solve the robot path planning problem under free space. The particle coding is coordinates of several path nodes in the environment. The number of spline curves and the maximum turnings of path were determined by the number of path nodes. The cubic spline function was used to interpolate on the path of the starting point, path nodes and target point, thus a full path which was formed by connecting all interpolation points was obtained. Simulation results show that …


Improved Marching Cubes Algorithmand Its Three-Dimensional Meteorological Simulation, Shuoben Bi, Lu Yuan, Xiaowen Zeng, Mingyue Lu, Yonghua Zhang Jun 2020

Improved Marching Cubes Algorithmand Its Three-Dimensional Meteorological Simulation, Shuoben Bi, Lu Yuan, Xiaowen Zeng, Mingyue Lu, Yonghua Zhang

Journal of System Simulation

Abstract: Methodof obtaining intersection points of isosurface and vowex by linear interpolation in original Marching Cubes algorithm has been replaced by the method of trisecting element boundaries. The problem of linear interpolation not suitable for meteorological data simulation is therefore solved and the number of triangular facets in isosurfacemapping is effectively reduced. While reducing redundancy and improving mapping speed, the quality of isosurface mapping is further improved. The improved Marching Cubes algorithm is applied to the simulation of meteorological model data, i.e., the isosurface of WRF data, and good results are obtained in both the speed of image rendering and …


Simulation On Psychosocial Adaption Of Urban New Migrants Based On Catastrophe Theory, Zhao Xu, Chuanchao Huang, Bin Hu Jun 2020

Simulation On Psychosocial Adaption Of Urban New Migrants Based On Catastrophe Theory, Zhao Xu, Chuanchao Huang, Bin Hu

Journal of System Simulation

Abstract: Based on the mental recovery and adaptive behavior translation of the new urban migrants, a two system decision-making model for psychological adaption was built. The simulation research of psychosocial adaption process was studied through the stochastic catastrophe theory and the specific artificial social environment. Simulation experiments indicate that the sustained pressure-bearing suffers from outside situation and the policy system result in the fluctuation of migrants' psychosocial adaption with the former more significant. In the translation of adaptive psychology to adaptive behavior, the attitude orientation and psychological cognition of migrants are critical. The duration or degree of the adaptive process …


Simulation Of Joint Power Control Routing Algorithm For Interference And Energy Consumption In Crahns, Zhufang Kuang, Zhigang Chen Jun 2020

Simulation Of Joint Power Control Routing Algorithm For Interference And Energy Consumption In Crahns, Zhufang Kuang, Zhigang Chen

Journal of System Simulation

Abstract: Problems of interference power to primary user by secondary userand the secondary user's running out of energy under underlay spectrum access model in cognitive radio ad hoc networks (CRAHNs) were investigated. Joint power control, routing and spectrum (channel) allocation algorithm (PRSA) based on particle swarm optimization were proposed. The goal of PRSA was to minimize interference power to primary user and prolong lifetime of CRAHNs. Particle encoding, particle initialization, fitness function, particle flight were included in PRSA. An Adjacency matrix with two-tuples containing allocated channel and power level was designed, and three operation rules for particle were redefined. …


Improved Design Scheme And Simulation Analysis Of Non-Valve Controlled Hydraulic Impact System, Liu Zhong, Zou Yu, Zhang Kai, Zhao Fei, Junjun Liu Jun 2020

Improved Design Scheme And Simulation Analysis Of Non-Valve Controlled Hydraulic Impact System, Liu Zhong, Zou Yu, Zhang Kai, Zhao Fei, Junjun Liu

Journal of System Simulation

Abstract: Due to valve port commutation of traditional hydraulic impact system caused valve leakage. For the above shortcomings, an improved structure principle of the new type of non-valve controlled hydraulic impact system was proposed establishing dynamic equations of impact system andconducting simulation analysis based on AMESim. Due to the simulation results which was inconsistent with design goal, two improvement schemes were proposed adding throttle device and controlling inlet and outlet circuit. The simulation results suggest that the working performance of impact system has been improved by adding throttle device, and its efficiency has been increased from 11.8% to 18.3% …


Inertia Effect In Dynamic Tensile Tests Of Concrete-Like Materials, Zhang Shu, Yubin Lu, Dongmei Zhao, Chen Xing Jun 2020

Inertia Effect In Dynamic Tensile Tests Of Concrete-Like Materials, Zhang Shu, Yubin Lu, Dongmei Zhao, Chen Xing

Journal of System Simulation

Abstract: The different understanding on the influential degree of the inertial effect does exist among researchers, and it has not been uniformly defined in dynamic tensile tests. The finite element numerical simulation method was employed to analyze the three typical dynamic tensile tests, without considering the real strain-rate effect in these models, where a constitutive model only considered the influence of hydrostatic pressure was used for modeling the specimen in these models. It is found that the dynamic tensile strength of concrete specimens in the three models mentioned is strengthened with the increase of loading strain-rate, owing to the …


Weld Trajectory Measurement Based On Stripe Type Laser Sensor, Li Lin, Weijie Chen, Yanbiao Zou Jun 2020

Weld Trajectory Measurement Based On Stripe Type Laser Sensor, Li Lin, Weijie Chen, Yanbiao Zou

Journal of System Simulation

Abstract: Teaching and playback are usually used on welding robot to weld a part. To make sure the implementation of this mode, it is needed to locate the part using artificial sport welding in the front process, which could cause location error and make the actual track deviate from the teaching track. A welding track offline detection device using stripe type laser sensor was proposed for solving the problem. The laser sensor was mounted at the end of the robot. The robot moved along the weld trajectory before welding. The information of the weld track section was gotten and the …


Novel Power Control Algorithm For Cognitive Radio Network, Long Min, Juanjuan Lei Jun 2020

Novel Power Control Algorithm For Cognitive Radio Network, Long Min, Juanjuan Lei

Journal of System Simulation

Abstract: For the problems of near-far effect, large path loss, and stability of algorithm, etc., in the cognitive radio, a new power control algorithm was proposed. Utility function was improved effectively, where punishment factors, such as, link quality and the interference capacity limit of the primary users (PUs) were considered. Signal-to-interference radio (SINR) of cognitive users (CUs) was controlled above the minimum threshold, and the interference value of the CUs was controlled below the capacity tolerance of PUs. The existence of Nash equilibrium was given. Simulation results show that the new algorithm has better stability; the loss of path …


Research On Feedback Compensation Control For Aircraft Electric Antiskid Brake System Based On Il, Gao Jie, Gao Bing, Jianying Liu Jun 2020

Research On Feedback Compensation Control For Aircraft Electric Antiskid Brake System Based On Il, Gao Jie, Gao Bing, Jianying Liu

Journal of System Simulation

Abstract: Safety, efficiency and comfort of aircraft are all determined by antiskid braking system. Because of the problem of inadequate control in the anti-skid braking system, the nonlinear model of the aircraft electric braking system was built by the analysis of aircraft landing process, and the iterative learning algorithm was introduced for reciprocating characteristics of anti-skid control. The groups in different speeds and road conditions were trained using the PD type learning rate. The knowledge base on the relationship among the optimal slip ratio and velocity and road conditions was built. The feed-forward control knowledge system for identifying the different …


Survey Of Studies On Numerical Simulations Of Optical-Wave Propagation In Atmospheric Turbulence, Bin Ren, Chunyi Chen, Huamin Yang Jun 2020

Survey Of Studies On Numerical Simulations Of Optical-Wave Propagation In Atmospheric Turbulence, Bin Ren, Chunyi Chen, Huamin Yang

Journal of System Simulation

Abstract: The complicated random behavior of atmospheric turbulence makes it difficult to verify the theories of optical-wave propagation in atmospheric turbulence by conducting experimental measurements. The parameters used in numerical simulations can be easily controlled; therefore numerical simulations have been used as another important tool to investigate the optical-wave propagation in atmospheric turbulence. Based on the existing literature, both the theoretical models and numerical generating methods for random phase screens of atmospheric turbulence are surveyed, and the spatial sampling constraints for numerical simulations of optical propagation in atmospheric turbulence were summarized. By comprehending the existing results, it has been pointed …


Genetic Algorithm For Solving Multi-Objective Dynamic Flexible Job Shop Scheduling, Wang Chun, Zhang Ming, Zhicheng Ji, Wang Yan Jun 2020

Genetic Algorithm For Solving Multi-Objective Dynamic Flexible Job Shop Scheduling, Wang Chun, Zhang Ming, Zhicheng Ji, Wang Yan

Journal of System Simulation

Abstract: To solve the scheduling problem of mold workshop in a toy factory with dynamic and flexible features, a mathematical model was established by introducing virtual operation and virtual working hours. Based on the strategies of periodic scheduling combined with dynamic event scheduling as well as the rolling window scheduling operation technology, dynamic scheduling was transformed into several continuous static scheduling windows, under which multi-objective genetic algorithm was used to solve the model. The priority of operation scheduling was given in different dynamic events. In addition, the encoding and anti-encoding of chromosome's operation sequence were made based on the proposed …


Fast Tree Modeling Method Based On Simple Freehand Sketch, Ma Ling, Xiaoping Liu, Xiaoping Liu Jun 2020

Fast Tree Modeling Method Based On Simple Freehand Sketch, Ma Ling, Xiaoping Liu, Xiaoping Liu

Journal of System Simulation

Abstract: Aiming at problems such as complicated process and professional knowledge requirements in tree modeling, a quick tree modeling method for non-experts was proposed, combining branch library with simple sketch to make non-experts create tree model quickly. The method preprocessed the sketch to eliminate noise and error points and identify the strokes, the trunk and branch were reconstructed, child three-dimensional profile was built through the two-dimensional canopy profile, under the constraint of the child profile, suitable branches from library and insert were extracted into the branches, consequently the whole tree model was completed. Experimental results show that this method …