Mechanical Engineering Commons^™

Optimal Power Flow Control Of Networked Dc Microgrids, Eddy H. Trinklein

Dissertations, Master's Theses and Master's Reports

The US military is moving toward the electrification of many weapon systems and platforms. Advanced weapon systems such as high energy radar, electro-magnetic kinetic weapons and directed energy pose significant integration challenges due to their pulsed power electrical load profile. Additionally, the weapons platforms, including ships, aircraft, and vehicles can be studied as a mobile microgrids with multiple generation sources, loads, and energy storage. There is also a desire to extend the mission profile and capabilities of these systems. Common goals are to increase fuel efficiency, maintaining system stability, and reduce energy storage size as typically required to enable pulsed …

Estimation And Prediction Of The Human Gait Dynamics For The Control Of An Ankle-Foot Prosthesis, Guilherme Aramizo Ribeiro

Dissertations, Master's Theses and Master's Reports

With the growing population of amputees, powered prostheses can be a solution to improve the quality of life for many people. Powered ankle-foot prostheses can be made to behave similar to the lost limb via controllers that emulate the mechanical impedance of the human ankle. Therefore, the understanding of human ankle dynamics is of major significance. First, this work reports the modulation of the mechanical impedance via two mechanisms: the co-contraction of the calf muscles and a change of mean ankle torque and angle. Then, the mechanical impedance of the ankle was determined, for the first time, as a multivariable …

Modeling And Control Of Maximum Pressure Rise Rate In Rcci Engines, Aditya Basina

Dissertations, Master's Theses and Master's Reports

Low Temperature Combustion (LTC) is a combustion strategy that burns fuel at lower temperatures and leaner mixtures in order to achieve high efficiency and near zero NOx emissions. Since the combustion happens at lower temperatures it inhibits the formation of NOx and soot emissions. One such strategy is Reactivity Controlled Compression Ignition (RCCI). One characteristic of RCCI combustion and LTC com- bustion in general is short burn durations which leads to high Pressure Rise Rates (PRR). This limits the operation of these engines to lower loads as at high loads, the Maximum Pressure Rise Rate (MPRR) hinders the use of …

Estimation Of Multi-Directional Ankle Impedance As A Function Of Lower Extremity Muscle Activation, Lauren Knop

Dissertations, Master's Theses and Master's Reports

The purpose of this research is to investigate the relationship between the mechanical impedance of the human ankle and the corresponding lower extremity muscle activity. Three experimental studies were performed to measure the ankle impedance about multiple degrees of freedom (DOF), while the ankle was subjected to different loading conditions and different levels of muscle activity. The first study determined the non-loaded ankle impedance in the sagittal, frontal, and transverse anatomical planes while the ankle was suspended above the ground. The subjects actively co-contracted their agonist and antagonistic muscles to various levels, measured using electromyography (EMG). An Artificial Neural Network …

Networked Microgrid Optimization And Energy Management, Robert S. Jane

Dissertations, Master's Theses and Master's Reports

Military vehicles possess attributes consistent with a microgrid, containing electrical energy generation, storage, government furnished equipment (GFE), and the ability to share these capabilities via interconnection. Many military vehicles have significant energy storage capacity to satisfy silent watch requirements, making them particularly well-suited to share their energy storage capabilities with stationary microgrids for more efficient energy management. Further, the energy generation capacity and the fuel consumption rate of the vehicles are comparable to standard diesel generators, for certain scenarios, the use of the vehicles could result in more efficient operation. Energy management of a microgrid is an open area of …

Online Learning Of The Spatial-Temporal Channel Variation In Underwater Acoustic Communication Networks, Wensheng Sun

Dissertations, Master's Theses and Master's Reports

Influenced by environmental conditions, underwater acoustic (UWA) communication channels exhibit spatial and temporal variations, posing significant challenges for UWA networking and applications. This dissertation develops statistical signal processing approaches to model and predict variations of the channel and relevant environmental factors. Firstly, extensive field experiments are conducted in the Great Lakes region. Three types of the freshwater river/lake acoustic channels are characterized in the aspects of statistical channel variations and sound propagation loss, including stationary, mobile and under-ice acoustic channels. Statistical data analysis shows that relative to oceanic channels, freshwater river/lake channels have larger temporal coherence, higher correlation among densely …

Resonant Acoustic Wave Assisted Spin-Transfer-Torque Switching Of Nanomagnets, Austin R. Roe

Theses and Dissertations

We studied the possibility of achieving an order of magnitude reduction in the energy dissipation needed to write bits in perpendicular magnetic tunnel junctions (p-MTJs) by simulating the magnetization dynamics under a combination of resonant surface acoustic waves (r-SAW) and spin-transfer-torque (STT). The magnetization dynamics were simulated using the Landau-Lifshitz-Gilbert equation under macrospin assumption with the inclusion of thermal noise. We studied such r-SAW assisted STT switching of nanomagnets for both in-plane elliptical and circular perpendicular magnetic anisotropy (PMA) nanomagnets and show that while thermal noise affects switching probability in in-plane nanomagnets, the PMA nanomagnets are relatively robust to the …

Immunity-Based Framework For Autonomous Flight In Gps-Challenged Environment, Mohanad Al Nuaimi

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this research, the artificial immune system (AIS) paradigm is used for the development of a conceptual framework for autonomous flight when vehicle position and velocity are not available from direct sources such as the global navigation satellite systems or external landmarks and systems. The AIS is expected to provide corrections of velocity and position estimations that are only based on the outputs of onboard inertial measurement units (IMU). The AIS comprises sets of artificial memory cells that simulate the function of memory T- and B-cells in the biological immune system of vertebrates. The innate immune system uses information about …

Energy Efficiency Evaluation Of Blower Heater Non-Purge Compressed Air Dryers, Alexandra M. Botts

Graduate Theses, Dissertations, and Problem Reports (ETD)

There are several compressed air dryers available for industrial use including, refrigerant, desiccant, and membrane. This research focuses on twin tower regenerative closed loop desiccant dryers, specifically: blower heater non-purge (BHNP) with and without cooling water pumps, Compressed-air Heater Purge (CHP), Blower Heater Purge (BHP), and Pressure Swing Heaterless (PSH). These styles of dryers are used mainly in industries that require extremely dry air such as, food manufacturing, medical air, or sensitive technology manufacturers. The research was conducted by collecting and analyzing real time current draw data on air compressors and associated dryers at eight different facilities (13 compressor systems) …

State Estimation For An Agonistic‐Antagonistic Muscle System, Thang Tien Nguyen, Holly Warner, Hung La, Hanieh Mohammadi, Daniel J. Simon, Hanz Richter

Electrical and Computer Engineering Faculty Publications

Research on assistive technology, rehabilitation, and prosthetics requires the understanding of human machine interaction, in which human muscular properties play a pivotal role. This paper studies a nonlinear agonistic‐antagonistic muscle system based on the Hill muscle model. To investigate the characteristics of the muscle model, the problem of estimating the state variables and activation signals of the dual muscle system is considered. In this work, parameter uncertainty and unknown inputs are taken into account for the estimation problem. Three observers are presented: a high gain observer, a sliding mode observer, and an adaptive sliding mode observer. Theoretical analysis shows the …

Optical Micro-Seismometer Based On Evanescent Field Perturbation Of Whispering Gallery Modes, Jaime Da Silva

Mechanical Engineering Research Theses and Dissertations

This thesis proposes a light-weight, compact, and accurate optical micro-seismometer that could be used in many applications, such as planetary exploration. The sensor proposed here is based on the principle of whispering gallery optical mode (WGM) resonance shifts of a dielectric micro-resonator due to disturbances of its evanescent field. The micro-seismometer could be used in place of the traditional bulky seismometers. The design of a waveguide-resonator and mechanical structure to disturb the evanescent field are presented. A proof-of-concept a seismometer model that uses a 5µm ring resonator is numerically tested with actual seismic data. The results show that a WGM-based …

Optimal Placement Of Distributed Energy Storage Systems In Distribution Networks Using Artificial Bee Colony Algorithm, Choton K. Das, Octavian Bass, Ganesh Kothapalli, Thair S. Mahmoud, Daryoush Habibi

Research outputs 2014 to 2021

The deployment of utility-scale energy storage systems (ESSs) can be a significant avenue for improving the performance of distribution networks. An optimally placed ESS can reduce power losses and line loading, mitigate peak network demand, improve voltage profile, and in some cases contribute to the network fault level diagnosis. This paper proposes a strategy for optimal placement of distributed ESSs in distribution networks to minimize voltage deviation, line loading, and power losses. The optimal placement of distributed ESSs is investigated in a medium voltage IEEE-33 bus distribution system, which is influenced by a high penetration of renewable (solar and wind) …

College Of Engineering Senior Design Competition Fall 2018, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …

Conversion Of Heat Energy From Cooling Water Of Diesel Engine To Electrical Energy Using Thermoelectric Generator, Muhammad Hasan Albana

Makara Journal of Technology

This research objective is to convert heat from the radiator fluid of a diesel engine to electrical energy by utilizing a thermoelectric generator (TEG). The TEG consists of 20 semiconductors (TE modules) and is equipped with a heat sink. The research shows that using the TEG, the heat of radiator fluid can be converted to electrical energy, although the electricity generated is small. The maximum electrical voltage generated by the TEG when modules were connected in series was 10 volts. When the TE modules were connected in parallel and series-parallel, the maximum voltages generated were 2.11 and 2.53 volts, respectively. …

Immittance Response On Carboxymethyl Cellulose Blend With Polyvinyl Alcohol- Doped Ammonium Bromide-Based Biopolymer Electrolyte, Norfatihah Mazuki, Yuki Nagao, Ahmad Salihin Samsudin

Makara Journal of Technology

The blended carboxymethyl cellulose (CMC) and polyvinyl alcohol (PVA) doped with various compositions of ammonium bromide (NH4Br)-based solid biopolymer electrolytes (SBEs) were prepared by using the casting method. In this present work, CMC/PVA–NH4Br SBE thin film was used to investigate the electrical conductivity via electrical impedance spectroscopy. The maximum conductivity obtained was 3.21 X 10−4 S cm−1 for sample AB20 at ambient temperature (303 K), and this result might be due to the increased number of charge carrier. A dielectric study was conducted to understand the conductivity behavior. The electrical properties have been measured as a function of frequency of …

Transition Metal Dichalcogenide For High-Performance Electrode Of Supercapacitor, Saifful Kamaluddin Muzakir, Ahmad Salihin Samsudin, Bouchta Sahraoui

Makara Journal of Technology

Molybdenum dichalcogenides have been reviewed from the perspectives of bandgap, conductivity, and oxidation states of transition metal. Researchers have concluded that a narrow-bandgap transition metal dichalcogenide with high conductivity could be achieved for the high-performance electrode of a supercapacitor.

Automated Compilation Test System For Embedded System, Mohamad Khairi Ishak, Ooi Jun Hwan, Teh Jiashen, Nor Ashidi Mat Isa

Makara Journal of Technology

Embedded system testing involves testing an integration of software and hardware. It is increasingly difficult to evaluate the functionality of each module within a short time because of the increasing number of tests required. In this paper, a novel stepwise methodology involving the use of an automated compilation test system (ACTS) is proposed, to improve the quality of testing and optimize the testing time using automation. Using the proposed method, the testing coverage can be maximized, while minimizing the manual work and testing time required. This ACTS was used to automate the test code compilation and execution for different hardware …

Activated Carbon Fixed-Bed Adsorber Design For Treating Chromium Hexavalent Wastewater, Tedi Hudaya, Velicia Rachmat

Makara Journal of Technology

Pollution caused by industrial wastewater containing heavy metals is a major issue, primarily due to its toxic nature. A cheap yet effective method to deal with such wastewater is activated carbon adsorption. The purpose of this research is to evaluate and design a fixed bed adsorber with granular activated carbon as an adsorbent to process wastewater-containing chromium hexavalent (Cr 6+). Experiments show that the Langmuir isotherm fits the equilibrium data as effectively as the Freundlich isotherm. Activated carbon used in this research is Jacobi 2000® derived from bituminous coal. The lab scale inlet volumetric flow is 100 mL/h with different …

A 2.3/3.3-Ghz Dual Band Low Noise Amplifier Using Switchable Load Inductor In 0.18-Um Cmos Technology, Taufiq Alif Kurniawan, Hsiao-Chin Chen

Makara Journal of Technology

In this paper, the dual band low noise amplifier is designed in 0.18-μm CMOS technology. By combining the proposed switchable load inductor for gain controlling and the conventional inductive source degeneration topology, narrow band gain and good impedance matching are achieved at 2.3/3.3-GHz frequency bands. The new mathematical analysis of low noise amplifier design is derived to define the component parameters of the proposed circuits. The proposed low noise amplifier exhibits gain of 17.18 dB and 15.5 dB, and noise figure of 2.67 dB and 2.52 dB at the two frequency bands, respectively.

Ascorbic Acid Degradation In Cut Lemon Packaged Using Oxygen Scavenging Active Film During Storage, Kurniawan Yuniarto, Setyo Purwanto, Bruce Ari Welt, Anang Lastriyanto

Makara Journal of Technology

Oxygen scavenging active film can be used to prevent diffusion of free oxygen due to the action of permeation mechanism. In this study, biodegradable oxygen scavenging plastic film was designed by incorporating an antioxidant agent into plasticized polylactic acid or PLA-PEG (PPLA). Butylated hydroxytoluene (BHT) was added at different concentrations into the matrix of the PPLA film using a direct casting method to produce oxygen scavenging active film. The antiradical activity of the oxygen scavenging active film was observed, which could be applied for preventing vitamin C degradation in cut lemon during storage. The antiradical activity of the active film …

The Importance Of Usability Aspect In M-Commerce Application For Satisfaction And Continuance Intention, Yassierli Yassierli, Vinsensius Vinsensius, M. S. Syed Mohamed

Makara Journal of Technology

There has been a rapid growing of m-commerce application in recent years due to the development of mobile communication technology and e-commerce business. However, only about 30% of online users, who conduct online searching, make online purchases. The low conversion rate seems to be correlated with poor usability aspect of most m-commerce applications and poor satisfaction reported by users. Research has reported that satisfaction and continuance intention in using m-commerce applications have relationships with service quality and information quality. In this study, a new model of user satisfaction and continuance intention in the context of mobile application was proposed by …

Development Of A Rapid Fatigue Life Testing Method For Reliability Assessment Of Flip-Chip Solder Interconnects, Cody Jackson Marbut

Graduate Theses and Dissertations

The underlying physics of failure are critical in assessing the long term reliability of power packages in their intended field applications, yet traditional reliability determination methods are largely inadequate when considering thermomechanical failures. With current reliability determination methods, long test durations, high costs, and a conglomerate of concurrent reliability degrading threat factors make effective understanding of device reliability difficult and expensive. In this work, an alternative reliability testing apparatus and associated protocol was developed to address these concerns; targeting rapid testing times with minimal cost while preserving fatigue life prediction accuracy. Two test stands were fabricated to evaluate device reliability …

Nanosatellite Launch Data-Logger (Sync), Christopher Martin Gerdom

Master's Theses

CubeSat designers are increasingly looking to incorporate delicate structures and optics into their payloads. These delicate payloads, however, may not survive the required absolute-worst-case launch vibration testing needed for flight certification. To help address this problem, and to better match testing conditions to real-world launch environments, this thesis introduces Sync, a compact 1/4U CubeSat payload designed to collect data on the vibrations and thermal environments CubeSats experience inside a deployer on the way to orbit. This data can be used to better understand the launch environment for different vehicles, and help develop new, more realistic testing guidelines that could enable …

Furnace System Improvements, Kenji K. Anzai, Ethan Fedor, Patrick Zailaa

Mechanical Engineering

This Final Design Review (FDR) documents the work done by the group to manufacture the system to deliver improvements to the furnace in the Cal Poly microfabrication laboratory (better known as the cleanroom). The document describes the material covered in the Scope of Work (SOW), including background research, customer needfinding, and the problem statement, material associated with concept development and selection for Preliminary Design Review (PDR), material detailing the design and manufacturing plan of the system for Critical Design Review (CDR), and new material detailing the manufacture of the system for FDR.

Research done for the SOW resulted in a …

Intelligent Application Of Flexible Ac Transmission System Components In An Evolving Power Grid, Robert Wall

Graduate Theses and Dissertations

The world revolves around energy and the energy sector is continually transforming and evolving. The status quo has been set by governing agencies in the United States for completely reliable power. The demand for energy efficiency continually rises for multiple reasons. Technology has improved for all sectors of the power grid, including renewable energy sources, fault protection, and SMART grid technology. The addition of new energy sources has led to the decommissioning of inefficient energy sources. The implementation of new technologies and power load on a large scale, coupled with the removal of grid stabilizers has posed different challenges that …

Comparative Study Of Power Semiconductor Devices In A Multilevel Cascaded H-Bridge Inverter, Kenneth Mordi

Graduate Theses and Dissertations

This thesis compares the performance of a nine-level transformerless cascaded H-bridge (CHB) inverter with integrated battery energy storage system (BESS) using SiC power MOSFETs and Si IGBTs. Two crucial performance drivers for inverter applications are power loss and efficiency. Both of these are investigated in this thesis. Power devices with similar voltage and current ratings are used in the same inverter topology, and the performance of each device is analyzed with respect to switching frequency and operating temperature. The loss measurements and characteristics within the inverter are discussed. The Saber® simulation software was used for the comparisons. The power MOSFET …

Transcribing Braille Code: Learning Equations Across Platforms, Deegan Atha, Courtney Balogh

Purdue Journal of Service-Learning and International Engagement

Deegan Atha, a graduating senior in electrical engineering and a future engineer, is interested in human-centered design and developing technology that helps students engage and be successful in STEM.

Courtney Balogh, a junior in mechanical engineering, is interested in human-centered design and the importance it plays in product development. Deegan and Courtney are members of the Purdue EPICS project, Learning Equations Across Platforms (LEAP). They partnered with the Indiana School for the Blind and Visually Impaired (ISBVI) to develop a braille transcription device and web application that converts braille to print in real time.

Cost Benefit Analysis Of Led Vs Florescent Lighting, Kurtis Clark, Phillip Humphrey

Student Research

Over the last few years, the state of Oklahoma has been looking at ways to reduce expenses to address concerns about a budget deficit. There have been efforts made to reduce expenses due to the use of energy. It has been said, when the lights are on, work is getting done. Running lights is therefore the cost of doing business. Our research examines the question, “is there a way to provide better lighting while operating at a lower cost.” This research examines the current lighting at Southwestern State University, primarily fluorescent lighting (FL), and a cost benefit analysis of switching …

Creating A Computational Tool To Simulate Vibration Control For Piezoelectric Devices, Ahmet Ozkan Ozer, Emma J. Moore

Posters-at-the-Capitol

Piezoelectric materials have the unique ability to convert electrical energy to mechanical vibrations and vice versa. This project takes a stab to develop a reliable computational tool to simulate the vibration control of a novel “partial differential equation” model for a piezoelectric device, which is designed by integrating electric conducting piezoelectric layers constraining a viscoelastic layer to provide an active and lightweight intelligent structure. Controlling unwanted vibrations on piezoelectric devices (or harvesting energy from ambient vibrations) through piezoelectric layers has been the major focus in cutting-edge engineering applications such as ultrasonic welders and inchworms. The corresponding mathematical models for piezoelectric …

Cfd Modeling On Hydrodynamic Characteristics Of Multiphase Counter-Current Flow In A Structured Packed Bed For Post-Combustion Co2 Capture, Li Yang, Fang Liu, Kozo Saito, Kunlei Liu

Mechanical Engineering Faculty Publications

Solvent-based post combustion CO₂ capture is a promising technology for industrial application. Gas-liquid interfaces and interactions in the packed bed are considered one of the key factors affecting the overall CO₂ absorption rate. Understanding the hydrodynamic characterizations within packed beds is essential to identify the appropriate enhanced mass transfer technique. However, multiphase counter-current flows in the structured packing typically used in these processes are complicated to visualize and optimize experimentally. In this paper, we aim to develop a comprehensive 3D multiphase, counter-current flow model to study the liquid/gas behavior on the surface of structured packing. The output from …