Engineering Commons^™

Multi-Homotopy Class Optimal Path Planning For Manipulation With One Degree Of Redundancy, Jacob J. Rice, Joseph M. Schimmels

Mechanical Engineering Faculty Research and Publications

Redundant manipulators have an infinitely large set of joint paths that yield a desired end-effector path in the task space. A unique joint path can be obtained by minimizing a global cost function. Prior optimal control methods minimize a global cost function to find a local minimum within a homotopy class. Many possible locally optimal joint paths are in different homotopy classes. This paper presents an algorithm that effectively searches the solution space and finds many locally optimal paths in all relevant homotopy classes. The path with the lowest cost is very likely the globally optimal path. The algorithm is …

Parametric Study Of A Triboelectric Transducer In Total Knee Replacement Application, Alwathiqbellah Ibrahim, Geofrey Yamomo, Ryan Willing, Shahrzad Towfighian

Mechanical Engineering Faculty Scholarship

Triboelectric energy harvesting is a relatively new technology showing promise for biomedical applications. This study investigates a triboelectric energy transducer for potential applications in total knee replacement (TKR) both as an energy harvester and a sensor. The sensor can be used to monitor loads at the knee joint. The proposed transducer generates an electrical signal that is directly related to the periodic mechanical load from walking. The proportionality between the generated electrical signal and the load transferred to the knee enables triboelectric transducers to be used as self-powered active load sensors. We analyzed the performance of a triboelectric transducer when …

Restoring Lake Urmia: Moving Beyond A Uniform Lake Level (2-Page Summary), Somayeh Sima, Dory Rosenberg, Wayne A. Wurtsbaugh, Sarah E. Null, Karin M. Kettenring

Watershed Sciences Faculty Publications

More than 5 million people live near Lake Urmia in northwestern Iran, one of the world's largest hypersaline lakes. Over the past two decades, the lake has lost 95% of its volume, lake level has dropped more than 7 m, and lake restoration has gained widespread interest. The government seeks a uniform "ecological" target lake level of 1274.1 m above sea level to lower salinity below 240 gL^-1 and recover brine shrimp (Artemia spp.) and flamingos (Phoenicopterus roseus).

We have synthesized over 40 years of available data, defined 8 ecosystem services for human health, water quality, ecology, recreation, and …

Simulation And Optimal Control Of Crude Oil Separation Process At Offshore Facilities To Improve Efficiency Of Oil And Condensate Recovery, Yee Kai Chin

Student Works (2020-2029)

Crude oil separation process is the most crucial process in offshore production facilities in ensuring the well fluid is separated efficiently and persistently. Waxy crude or sluggish feed stream is the major disturbance that could cause operational issues and production loss due to process upset. The main objective of this research is to model offshore crude oil separation process and introduce state space control to optimize the control of total liquid and water level within the permissible range as well as to evaluate the effect of disturbances to the controls. This work presents two different modelling methods in developing three-phase …

Improving Client-Consultant-Contractor Communication In Construction Industry Through Whatsapp Application, Muhammad Hafizul Taib

Student Works (2020-2029)

A Smooth and effective communication is very important in construction industry to prevent iteration and rework which will cause money. Since there are a lot of parties involve in construction,it is important to have a good communication platform. In the current world, people are using the technology advancement to enhance the effectiveness of communication amongst people who work in construction industry. Though there are a lot of mobile application designed for construction purpose, WhatsApp is the most commonly used by all. However, there are no studies done to identify the effectiveness of it. This thesis will gather respond from client, …

Challenges In E-Tendering Implementation In Ministry Of Youth And Sports Malaysia, Azis Ahmad Zamie

Student Works (2020-2029)

The Ministry of Youth and Sport, like most ministries in Malaysia, tenders its projects through the traditional paper-based tendering process, which has many weaknesses, including bureaucracy and lack of transparency. In 2008, e-Tender was one of government incentive under e-Government application was introduced to replace manual tendering system in public agencies to systematic procurement which using internet as platform of transaction. Like any other transition project, implementation of e-tender in Ministry of Youth and Sport, is associated with several challenges. This research aims to explore the challenges facing the implementation of the e-tender system in the Ministry of Youth and …

A Multicriteria Aware Optimal Routing Approach For Enhancing Quality Of Service In Device To Device Communication, Tilwari Valmik

Student Works (2020-2029)

As the world is moving towards the digitalization era, increasing demands of higher data rates, energy effiffifficiency, and seamless connectivity are skyrocketing. Device-to-Device (D2D) communication is one of the key technologies for future Fifth Generation (5G) network. D2D communication technology enhances network coverage, boosts spectral efficiency, has low latency, and enables the devices to communicate with each other, with partial or none involvement of network infrastructure. Therefore, factors of such nature make D2D communication a promising medium guarantying reliability to several telecommunications scenarios. D2D caters to all the needs of it’s users, from the high demand of peer-to-peer users for …

Multimode-Interference Based Optical Fiber Sensor For Civil Structures Monitoring, Sue Ping Chew

Student Works (2020-2029)

The thesis describes the experimental investigations on the multimode interferencebased fiber sensors using single mode multimode single mode (SMS) and multimode single mode multimode (MSM) structures as a sensing device for structural health monitoring (SHM) applications. Both sensor structures were fabricated, characterized and tested for detecting strain and vibration in civil infrastructures. The proposed SMS structure comprises of a short segment of multimode fiber (MMF), which were fusionspliced by two single mode fibers (SMFs) at both terminals. On the other hand, MSM was fabricated by splicing SMF with MMF at both ends. A new packaging technique for the SMS structure …

Syntheses, Characterisations And Electrochemical Studies Of Nickel(Ii) And Cobalt(Ii)-Ligand Assisted Cooperative Complexes, Subramaniam Jeevithra Dewi

Student Works (2020-2029)

A newly designed tetradentate ligand L1 (L1 = 3,6-bis(pyrazol-1-yl)-pyridazine) which offers multinucleation sites on its moiety structure has been prepared. The reaction of L1 with different molar ratio of nickel and cobalt salts lead to the formation of di- and tetranuclear complexes [NiII 2(L1)2(CH3CN)4](PF6)4 (1), [NiII 4(L1)4(μ-OH)4](ClO4)4 (2) and [CoII/III(L1)4(μ-CH3O)2(μ-O)2](PF6)3(NO3) (3), which served as the attempt to design of catalysts based on cheap and earth-abundant metals for carbon dioxide reduction. The presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as the base controls the nuclearity of the complex formation. In the absence of DBU, complex 1 was formed in dinuclear fashion whereas complex 2 …

Engineering Properties And Microstructural Characteristics Of Cement And Geopolymer Based Mortars Using Nontraditional Supplementary Cementitious Materials, Mathialagan Sumesh

Student Works (2020-2029)

The concrete repair and rehabilitation industry grows rapidly due to deterioration, damage and defects in concrete structures. For various reasons, the concrete construction industry is not sustainable; because it consumes huge quantities of virgin materials, the usage of Portland cement as prime binder. The production of cement is a major contributor to greenhouse gas emissions. In addition, the high cost of commercial repair material. Therefore, it is necessary to develop cost-effective alternative repair materials for concrete repairs. There have been many standard repair materials available in the market, which are costly and not affordable to common people. However, research works …

Optimal Network Reconfiguration And Distributed Generation Sizing With Consideration Of Protection System, Abdul Rahim Mohamad Norshahrani

Student Works (2020-2029)

Research on network reconfiguration (NR) considering distributed generation (DG) commonly focus on the issues of power loss, voltage deviation, DG sizing and its placement. These works are important and required in the planning stage of the distribution networks. In most of the past works, the protection system is neglected in this stage although it is essential to prevent the network from damages during operation. Without proper consideration of protection system settings and coordination during NR, the protection system may operate inaccurately. This happens due to changes in current flow and fault level when the network changes its configuration. As a …

Development Of Nano Carbon And Conducting Polymers Based Ternary Composites For Supercapattery, Iqbal Javed

Student Works (2020-2029)

Although significant efforts have been devoted on the development of energy storage systems such as batteries and fuel cells in the past decades, the low power density, short cyclic life and high maintenance cost have kept them away from many applications. Alternatively, supercapattery which has the characteristic features of batteries as well as supercapacitors has gained much attention because of its rapid charge/discharge mechanism, long life cycle, and high power density. However, supercapattery generally suffers from poor energy density. This research aims to develop carbon and conducting polymers based ternary nanocomposites for high performance supercapattery. Pristine metal oxide nanostructures suffer …

Combining Machine Learning And Empirical Engineering Methods Towards Improving Oil Production Forecasting, Andrew J. Allen

Master's Theses

Current methods of production forecasting such as decline curve analysis (DCA) or numerical simulation require years of historical production data, and their accuracy is limited by the choice of model parameters. Unconventional resources have proven challenging to apply traditional methods of production forecasting because they lack long production histories and have extremely variable model parameters. This research proposes a data-driven alternative to reservoir simulation and production forecasting techniques. We create a proxy-well model for predicting cumulative oil production by selecting statistically significant well completion parameters and reservoir information as independent predictor variables in regression-based models. Then, principal component analysis (PCA) …

Development And Optimization Of Imaging And Image Quantification Techniques For Tissue-Engineered Blood Vessel Mimics, Ashley Turcott

Master's Theses

Blood vessels mimics (BVMs) are tissue-engineered blood vessels used to test vascular devices in an environment that mimics some simple anatomical factors of native blood vessels. It is important to accurately and consistently assess tissue-engineered blood vessels, although there is currently a lack of standardization in Cal Poly’s Tissue Engineering Lab and in the entirety of the field. The goal of this thesis was to develop and optimize imaging and image quantification techniques for tissue-engineered blood vessels.

The first aim of this thesis optimized and compared imaging and assessment techniques for electrospun scaffolds. Images from different SEMs were compared to …

Identification Of Users Via Ssh Timing Attack, Thomas J. Flucke

Master's Theses

Secure Shell, a tool to securely access and run programs on a remote machine, is an important tool for both system administrators and developers alike. The technology landscape is becoming increasingly distributed and reliant on tools such as Secure Shell to protect information as a user works on a system remotely. While Secure Shell accounts for the abuses the security of older tools such as telnet overlook, it still has fundamental vulnerabilities which leak information about both the user and their activities through timing attacks. The OpenSSH client, the implementation included in all Linux, Mac, and Windows computers, sends each …

Dynamics Of Discontinuities In Elastic Solids, Arkadi Berezovski, Mihhail Berezovski

Publications

The paper is devoted to evolving discontinuities in elastic solids. A discontinuity is represented as a singular set of material points. Evolution of a discontinuity is driven by the configurational force acting at such a set. The main attention is paid to the determination of the velocity of a propagating discontinuity. Martensitic phase transition fronts and brittle cracks are considered as representative examples.

Synthesis And Fabrication Of Self-Sustainable Triboelectric Energy Case For Powering Smart Electronic Devices, Abu Masa Abdullah, Alejandro Flores, Aminur Rashid Chowdhury, Jianzhi Li, Yuanbing Mao, M. Jasim Uddin

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

In recent times, Triboelectric Nanogenerators (TENG) have attained the focus of the scientific community due to its potential as a medium to harvest mechanical energy from the ambient environment. Human motion has been attributed as a source of mechanical energy to drive electronic devices and sensors through TENG. Based on the principles of single electrode TENG, we have developed a Triboelectricity based Stepping and Tapping Energy Case (TESTEC) which magnifies the prospect to power touch electronic devices by utilizing finger tapping and stepping motion. This novel case was constructed with two single electrode TENG operating through the triboelectric mechanism between …

National Summer Transportation Institute: Increasing Career Awareness In Civil Engineering For Underserved High School Students, Melanie L. Villatoro, Janet Liou-Mark

Publications and Research

Our nation needs to increase the number of students pursuing degrees in the fields of Science, Technology, Engineering, and Mathematics (STEM) and those leading to transportation-related careers. In order to meet the demand for qualified graduates in transportation, it is necessary to diversify the pool of students entering college with an interest in these fields. The National Summer Transportation Institute (NSTI) is an educational initiative developed by the Federal Highway Administration (FHWA) and Department of Transportation (DOT). The NSTI at City Tech was designed to increase awareness of transportation-related careers among New York City high school students. The structure of …

Optimization Of Railroad Bearing Health Monitoring System For Wireless Utilization, Jonas Cuanang, Constantine Tarawneh, Martin Amaro Jr., Jennifer Lima, Heinrich D. Foltz

Mechanical Engineering Faculty Publications

In the railroad industry, systematic health inspections of freight railcar bearings are required. Bearings are subjected to high loads and run at high speeds, so over time the bearings may develop a defect that can potentially cause a derailment if left in service operation. Current bearing condition monitoring systems include Hot-Box Detectors (HBDs) and Trackside Acoustic Detection Systems (TADS™). The commonly used HBDs use non-contact infrared sensors to detect abnormal temperatures of bearings as they pass over the detector. Bearing temperatures that are about 94°C above ambient conditions will trigger an alarm indicating that the bearing must be removed from …

Processing-Structure-Property Relationships Of Biopolyester/Zinc Oxide Fibrous Scaffolds Engineered By Centrifugal Spinning, Victoria Padilla-Gainza, Heriberto Rodríguez-Tobías, Graciela Morales, Antonio Ledezma-Pérez, Carmen Alvarado-Canché, Cristobal Rodriguez, Robert Gilkerson, Karen Lozano

Mechanical Engineering Faculty Publications

This study addresses the processing of nonwoven fibrous materials obtained by centrifugal spinning method, namely Forcespinning; a high yield and low production cost technique little explored in this field. Poly(D, L-lactic acid) (PDLLA) and poly(3-hydroxybutyrate) (PHB) were used as matrices and reinforced with zinc oxide nanoparticles (n-ZnO). The morphology, mechanical, and thermal performance of the developed composites were analyzed as well as the antibacterial effect of n-ZnO. Fibrous materials with n-ZnO concentrations of 1, 3, and 5 wt. % for PDLLA and 1 and 3 wt. % for PHB were evaluated. The results showed that the incorporation of n-ZnO produces …

Socio-Technical Transitions In The Water Sector: Emerging Boundaries For Utility Resilience In Barbados, Wainella N. Isaacs

USF Tampa Graduate Theses and Dissertations

Resilience is gaining popularity in the water sector where it described as contributing to reduced vulnerability to water-related risks and hazards including climate change. Unfortunately, literature in this area, contributed mainly from North America and Europe, is fragmented with a concentration on engineering resilience in water supply infrastructure. The absence of any scholarship on resilience for a small island nation, coupled with the absence of sociological contributors to building resilience in this sector motivated this research.

The goal of this research was to understand and evaluate how resilience is characterized and operationalized in the Barbados water and wastewater infrastructure system, …

Effects Of Physical And Chemical Characteristics Of Slags And Cements On Durability Of Portland Cement-Slag Blended Systems, Farzaneh Nosouhian

USF Tampa Graduate Theses and Dissertations

Ground granulated blast furnace slag (GGBFS) which is a commonly used supplementary cementitious material (SCM) needs to be more investigated for improving durability of concrete elements and service life of concrete structures. This research focuses on the effect of the physical and chemical characteristics of GGBFS and portland cement on durability of portland cement-slag blended systems. The effect of cement replacement level is also investigated using control mixes (no slag) and four different levels of slag content. To this end, eight GGBFS and eight portland cements were selected based on their physical characteristics and chemical composition. Four series of experimental …

Fabrication And Characterization Of Flexible Three-Phase Zno-Graphene-Epoxy Electro-Active Thin-Film Nanocomposites: Towards Applications In Wearable Biomedical Devices, Mandeep Singh, Sanjeev Kumar, Shervin Zoghi, Debaki Sarcar, Saquib Ahmed, Shaestagir Chowdhury, Sankha Banerjee

Mechanical and Materials Engineering Faculty Publications and Presentations

Perovskite oxides have been used as sensors, actuators, transducers, for sound generation and detection, and also in optical instruments and microscopes. Perovskite halides are currently considered as optoelectronic devices such as solar cells, photodetectors, and radiation detection, but there are major issues with stability, interfacial recombination, and electron/hole mobility. The following work looks into the fabrication of non-toxic ZnO-based lead-free alternatives to perovskite oxides for use as secondary sensors or electron transport layers along with perovskite halides for application in stacked biomedical wearable devices. Three-phase, lead-free, Zinc Oxide-Graphene-Epoxy electroactive nanocomposite thin films were fabricated. The volume fraction of the Graphene …

Guided-Wave Shm And Nde Of Composite Structures: Modeling And Experiments, Hanfei Mei

Theses and Dissertations

The extensive use of composites in aerospace structures has posed new challenges for implementing effective structural health monitoring (SHM) and nondestructive evaluation (NDE) techniques due to the general anisotropic behavior and complex damage scenarios in composites. This dissertation addresses the SHM and NDE of composites using ultrasonic guided waves, with an emphasis on theoretical modeling and experimental validation of guided-wave propagation and interaction with damage in composites. A semi-analytical finite element (SAFE) approach is presented to calculate guided-wave dispersion curves in composites. The theoretical framework is formulated using the finite element method (FEM) to describe the material variation along the …

Fundamental Understanding Of Plasma Discharge Formation In Liquid And Multiphase Configurations Through Multiphysics Modeling, Ali Charchi Aghdam

Theses and Dissertations

During the last two decades, non-thermal plasma discharges in and in contact with liquids have received significant attention due to their wide range of applications including chemical analysis, medical, water treatment, fuel processing, etc. Despite the tremendous interest and advances attained in the experimental studies, modeling efforts providing a comprehensive understanding of the underlying physicochemical processes are limited. There is still no unified theory on plasma formation in dense medium and various theories have been proposed such as the presence of bubbles and tunneling which are topics of debate. In the first part of this study, a mathematical model is …

Evaluation Of Temporal Damage Progression In Concrete Structures Affected By Asr Using Data-Driven Methods, Vafa Soltangharaei

Theses and Dissertations

Alkali-silica reaction (ASR) is a chemical reaction, which causes damage in concrete structures such as bridges, dams, and nuclear containments and powerplant structures. The ASR-induced damage may endanger the integrity and serviceability of structures. Several methods such as visual inspection, petrographic analysis, demountable mechanical strain gauges, and cracking index have been utilized for study the effect of ASR on structures, which are not always efficient in early damage detection and some are destructive and prohibited in nuclear structures. Nondestructive methods and structural health monitoring techniques can be alternatives for the condition assessment of structures. Among the nondestructive methods, acoustic emission …

An Aviation Weather Preflight Decision Support Tool To Improve Ga Pilots' Preflight And Inflight Performance, Jayde M. King

Doctoral Dissertations and Master's Theses

Low hour, inexperienced General Aviation (GA) pilots account for the majority of weather-related incidents, which often result in fatalities. Previous research identifies poor preflight planning practices and a lack of aviation weather knowledge as key contributing factors to the high novice private pilot accident and fatality rate. Research invested into resolving these issues often attempt to introduce new inflight weather technology to assist pilots with weather avoidance. However, these interventions usually result in pilots using the information to strategically navigate closer to degraded weather conditions (Beringer & Ball, 2004; Burgess & Thomas, 2004). Therefore, the purpose of this study was …

Optimum Mixing Design Of Xanthan And Gellan Treated Soils For Slope Stabilization For Weathered Shales And Glacial Tills In Nebraska, Layal Bitar

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Verdigre located in North Eastern Nebraska experienced slope failures. The geological formations of theses slopes largely consist of several layers of weathered shales and glacial tills. It is believed that the weathering process reduced the shear strength of the soils leading to slope failures.

In this study, strength characteristics of Xanthan and Gellan gums treated soil specimens compacted at the optimum moisture content for field application were investigated so that the biopolymer treated soils may be properly used to stabilize the slopes. The untreated and treated samples were subjected to a wet-freeze(-6^oF)-thaw(167^oF)-dry weathering process up to …

Development Of A Mash Test Level 4 Open Concrete Bridge Rail, Jacob Delone

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

An open concrete bridge rail was designed and developed according to safety performance guidelines in the American Association of State Highway Transportation Officials (AASHTO) Manual for Assessing Safety Hardware (MASH) for Test Level 4 (TL-4). Systems designed and developed under previous guidance were studied, and their geometric information and full-scale crash testing performance was studied to establish the geometry of the new bridge rail. Yield-Line Theory and the AASHTO Post and Beam design methods were studied, and a modified version of the AASHTO Post and Beam method was utilized to determine the capacity of the new open concrete bridge rail. …

Study On New Sampling Plans And Optimal Integration With Proactive Maintenance In Production Systems, Sinan Obaidat

Graduate Theses and Dissertations

Sampling plans are statistical process control (SPC) tools used mainly in production processes. They are employed to control processes by monitoring the quality of produced products and alerting for necessary adjustments or maintenance. Sampling is used when an undesirable change (shift) in a process is unobservable and needs time to discover. Basically, the shift occurs when an assignable cause affects the process. Wrong setups, defective raw materials, degraded components are examples of assignable causes. The assignable cause causes a variable (or attribute) quality characteristic to shift from the desired state to an undesired state.

The main concern of sampling is …