Engineering Commons^™

Investigation Of Through Thickness Microstructure And Mechanical Properties In Friction Stir Welded 7n01 Aluminum Alloy Plate, Xingxin Zhao, Zhiyong Yang, Joseph P. Domblesky, Jianmin Han, Zhiqiang Li, Xiaolong Liu

Mechanical Engineering Faculty Research and Publications

An on-going problem in friction stir welded (FSW) joints used in the high-speed train sector is that the microstructure and mechanical properties can significantly vary in thick sections. Because inhomogeneous properties can reduce weld efficiency and degrade service performance, it is of some interest to understand how inhomogeneous properties can develop in FSW welds made from precipitation hardening alloys such as 7N01. In the current study, butt welds were made using 12 mm thick plates and then sectioned perpendicular to the weld line. Five 2.2 mm thick slices were cut from a section and used to measure tensile properties access …

Computational Analysis Of 3d Lattice Structures For Skin In Real-Scale Camber Morphing Aircraft, Bashir Alsaidi, Woong Yeol Joe, Muhammad Akbar

Mechanical and Manufacturing Engineering Faculty Research

Conventional or fixed wings require a certain thickness of skin material selection that guarantees structurally reliable strength under expected aerodynamic loadings. However, skin structures of morphing wings need to be flexible as well as stiff enough to deal with multi-axial structural stresses from changed geometry and the coupled aerodynamic loadings. Many works in the design of skin structures for morphing wings take the approach either of only geometric compliance or a simplified model that does not fully represent 3D real-scale wing models. Thus, the main theme of this study is (1) to numerically identify the multi-axial stress, strain, and deformation …

Range Of Motion Evaluation Of A Final Frontier Design Iva Spacesuit Using Motion Capture, Ryan L. Kobrick, Nicholas Lopac, Chase Covello, Benjamin Banner, Theodore Southern, Nikolay Moiseev

Publications

Embry-Riddle Aeronautical University’s Spacesuit Utilization of Innovative Technology Laboratory (S.U.I.T. Lab) is focused on improving human performance in spaceflight by concentrating on spacesuit research for intravehicular activities (IVA) and extravehicular activities (EVA). The design and execution of range of motion (ROM) protocols in an experimental setting will provide insight on the functions and restrictions of spacesuits, aiding in current and future designs or modification. The S.U.I.T. Lab worked with Final Frontier Design (FFD) to provide a quantitative analysis protocol for seated arm mobility of their NASA Flight Opportunities Program (FOP) IVA spacesuit. The lab used reflective tracking markers on three …

Features Of Designing The Architecture Of Intelligent Transport Systems, Jaffar Daeibal, Vyacheslav Lapshin, Dmitry Elkin, Sergey A. Kucherov

Karbala International Journal of Modern Science

In the global experience, intelligent transport systems (ITS) are recognized as a general transport ideology for integrating the achievements of telematics in all types of transport activities to solve economic and social problems: reducing accidents, improving the efficiency of public transport and cargo transportation, ensuring overall transport security, and improving environmental performance. Considering the design features of the intelligent transport system (ITS), there is a need to develop requirements for the functional and physical architecture as the main part of the ITS development. The creation of functional and physical architecture touches upon issues such as: the scheme of interaction between …

Field Monitoring Of A Tieback Wall And Comparison To Common Design Methods, Matheus Barbosa Santos De Miranda

Graduate Theses - Civil Engineering

This thesis presents the monitoring of a 28-foot high retaining wall located on the Rose- Hulman Institute of Technology (RHIT) campus and compares inclinometer and load cell data with common design methods. In addition, it briefly provides discussion regarding how the retaining structure is used to enhance student learning. The wall consists of soldier piles and wood lagging with tiebacks that vary from 22.5 to 40 feet. Construction was completed in 2017. Instrumentation, including load cell and inclinometers were installed to measure deflection, tieback load, and water level. This thesis describes the construction activities and the data gathered to date. …

Engineering Of Bio-Mimetic Substratum Topographies For Enhanced Early Colonization Of Filamentous Algae, Ali Khoshkhoo, Andres L. Carrano, David M. Blersch, Kamran Kardel

Manufacturing Engineering: Faculty Publications (2015-2023)

This work reveals a set of surface topography parameters that are significant for algal attachment to natural rock substrata. Topography analysis of rock surfaces from a stream identifies three descriptive areal parameters (Smr, Sv, and Sa) that correlate with the presence of natural periphyton community. A method was developed and validated to reverse engineer and manufacture artificial substrata with topographic complexity defined by these parameters, using computational modeling and additive manufacturing. Results from colonization experiments with filamentous algae show statistically significant increases in early biomass accrual rates on substrata with higher values of …

Gpu-Based Graph Traversal On Compressed Graphs, Mo Sha, Yuchen Li, Kian-Lee Tan

Research Collection School Of Computing and Information Systems

Graph processing on GPUs received much attention in theindustry and the academia recently, as the hardware accelerator offers attractive potential for performance boost. However, the high-bandwidth device memory on GPUs has limited capacity that constrains the size of the graph to be loadedon chip. In this paper, we introduce GPU-based graph traversal on compressed graphs, so as to enable the processingof graphs having a larger size than the device memory. Designed towards GPU’s SIMT architecture, we propose twonovel parallel scheduling strategies Two-Phase Traversal andTask-Stealing to handle thread divergence and workload imbalance issues when decoding the compressed graph. Wefurther optimize our …

High-Performance Polyvinyl Chloride Gel Artificial Muscle Actuator With Graphene Oxide And Plasticizer, Taeseon Hwang, Zachary Frank, Justin Neubauer, Kwang Jin Kim

Mechanical Engineering Faculty Research

A transparent and electroactive plasticized polyvinyl chloride (PVC) gel was investigated to use as a soft actuator for artificial muscle applications. PVC gels were prepared with varying plasticizer (dibutyl adipate, DBA) content. The prepared PVC gels were characterized using Fourier-transform infrared spectroscopy, thermogravimetric analysis, and dynamic mechanical analysis. The DBA content in the PVC gel was shown to have an inverse relationship with both the storage and loss modulus. The electromechanical performance of PVC gels was demonstrated for both single-layer and stacked multi-layer actuators. When voltage was applied to a single-layer actuator and then increased, the maximum displacement of PVC …

Evaluation Of Field Of View Width In Stereo-Vision-Based Visual Homing, Damian Lyons, Benjamin Barriage, Luca Del Signore

Faculty Publications

Visual homing is a local navigation technique used to direct a robot to a previously seen location by comparing the image of the original location with the current visual image. Prior work has shown that exploiting depth cues such as image scale or stereo-depth in homing leads to improved homing performance. While it is not unusual to use a panoramic field of view (FOV) camera in visual homing, it is unusual to have a panoramic FOV stereo-camera. So, while the availability of stereo-depth information may improve performance, the concomitant-restricted FOV may be a detriment to performance, unless specialized stereo hardware …

The Roussopoulos And Schwinger Functionals For Nuclear Systems Involving Imprecisely Known Fluxes And Parameters: Distinctions And Equivalences, Dan Gabriel Cacuci

Faculty Publications

For over 60 years, the Roussopoulos and Schwinger functionals have been used in many works and textbooks under the assumption that they provide “second-order accurate” trial functions for the forward and adjoint fluxes when computing reaction rates and/or particle detector responses in source-driven nuclear systems. The Schwinger functional has been employed as a particularly useful form of the Roussopoulos functional for systems in which the forward and adjoint particle fluxes were normalized. When using these functionals, however, the expressions for the approximate fluxes were postulated arbitrarily while the system parameters were unrealistically assumed to be perfectly well known. This work …

Personalized Product Evaluation Based On Gra-Topsis And Kansei Engineering, Huafeng Quan, Shaobo Li, Hongjing Wei, Jianjun Hu

Faculty Publications

With the improvement of human living standards, users’ requirements have changed from function to emotion. Helping users pick out the most suitable product based on their subjective requirements is of great importance for enterprises. This paper proposes a Kansei engineering-based grey relational analysis and techniques for order preference by similarity to ideal solution (KE-GAR-TOPSIS) method to make a subjective user personalized ranking of alternative products. The KE-GRA-TOPSIS method integrates five methods, including Kansei Engineering (KE), analytic hierarchy process (AHP), entropy, game theory, and grey relational analysis-TOPSIS (GRA-TOPSIS). First, an evaluation system is established by KE and AHP. Second, we define …

Phosphine Oxide Containing Poly(Pyridinium Salt)S As Fire Retardant Materials, Maksudul M. Alam, Bidyut Biswas, Alexi K. Nedeltchev, Haesook Han, Asanga D. Ranasinghe, Pradip K. Bhowmik, Kisholoy Goswami

Chemistry and Biochemistry Faculty Research

Six new rugged, high-temperature tolerant phosphine oxide-containing poly(4,4′-(p-phenylene)-bis(2,6-diphenylpyridinium)) polymers P-1, P-2, P-3, P-4, P-5, and P-6 are synthesized, characterized, and evaluated. Synthesis results in high yield and purity, as confirmed by elemental, proton (1H), and carbon 13 (13C) nuclear magnetic resonance (NMR) spectra analyses ... See full text for complete abstract.

Statistical Learning Of Biomedical Non-Stationary Signals And Quality Of Life Modeling, Mahdi Goudarzi

USF Tampa Graduate Theses and Dissertations

Statistical learning is a set of tools for modeling and understanding complex datasets. It is a recently developed area in statistics and blends with parallel developments in computer science and, in particular, machine learning.

The classification of biomedical non-stationary signals such as Electroencephalogram (EEG) is always a challenging problem due to their complexity. The low spatial resolution on the scalp, curse of dimensionality, poor signal-to-noise ratio are disadvantages of working with biomedical signals. EEG signals are unstructured data which needs preprocessing steps to extract informative features which are measurable and predictive. In the first two chapters of this dissertation, EEG …

Bamboo As A Sustainable Engineering Material: Mechanical Properties, Safety Factors, And Experimental Testing, Lorena Sánchez Vivas

USF Tampa Graduate Theses and Dissertations

With exponential global population growth occurring and associated environmentally destructive consumption of natural resources, alternative materials that are fast growing and sustainable are being sought out to satisfy human needs. One material that is fast growing and sustainable that can be used to meet most basic needs of humans (i.e. shelter, food, tools) is the plant bamboo, of the grass family Poaceae. Bamboo was used in the past by native peoples who lived in the environment where bamboo natively grows (all continents except Europe and Antarctica) with proven success for uses such as shelter, piping, tools, wells, food, fencing, baskets …

Mhealth Elisa System For Point-Of-Care, Arsenii Zhdanov

USF Tampa Graduate Theses and Dissertations

Enzyme-linked immunosorbent assay (ELISA) is one of the most important technologies for biochemical analysis critical for diagnosis and monitoring of many diseases. Traditional systems for ELISA incubation and reading are expensive and bulky, thus cannot be used at pointof- care or in the field. Here, we design and demonstrate a new miniature mobile phone based system for ELISA. This mHealth system can be used to complete all steps of the assay, including incubation and reading. It can be fabricated at low cost, portable, and can transfer test results via mobile phone. We have designed the sample dispensing system, incubation chamber, …

Potential For On-Site, Prosecutorial Evidence From Drug Residues Collected On Plasmonic Paper: A Pilot Study For Sers-Psi-Ms, Daniel S. Burr

Theses and Dissertations

Given the potential impact of improvements to on-site drug testing, as well as recent, successful displays of paper spray ionization mass spectrometry (PSI-MS) in this regard, this thesis pilots the implementation of Raman spectroscopy as a compliment to MS for field-based confirmatory drug testing. Surface enhanced Raman scattering (SERS) is utilized for applications to trace detection. Two-tiered analysis of individual drug samples is enabled using triangularly-cut plasmonic papers, from which both SERS and PS-MS analysis may be performed. Several drug compounds, representative of traditional and emerging drug types, are examined by these techniques, both separately and as a fully integrated, …

Twenty-Three Unsolved Problems In Hydrology (Uph) – A Community Perspective, Günter Blöschl, Marc F.P. Bierkens, Antonio Chambel, Christophe Cudennec, Georgia Destouni, Aldo Fiori, James W. Kirchner, Jeffrey J. Mcdonnell, Hubert H.G. Savenije, Murugesu Sivapalan, Christine Stumpp, Elena Toth, Elena Volpi, Gemma Carr, David G. Tarboton, Et. Al

Civil and Environmental Engineering Faculty Publications

This paper is the outcome of a community initiative to identify major unsolved scientific problems in hydrology motivated by a need for stronger harmonisation of research efforts. The procedure involved a public consultation through online media, followed by two workshops through which a large number of potential science questions were collated, prioritised, and synthesised. In spite of the diversity of the participants (230 scientists in total), the process revealed much about community priorities and the state of our science: a preference for continuity in research questions rather than radical departures or redirections from past and current work. Questions remain focused …

Design Of Variable Wall Thickness Geometry And Performance Mapping Of Scroll Expanders For Distributed Power Generation, Arun Kumar Narasimhan

USF Tampa Graduate Theses and Dissertations

Low-temperature heat sources such as industrial waste heat, solar, and geothermal are more suitable for small-scale power generation rather than utility scale. In order to maximize the electricity generated from low-temperature heat sources, an efficient expansion device for small-scale power output is necessary. This research work has focused on evaluating the use of a scroll expander and improving its geometrical design for the power output range of 1-25 kW_e.

The first part of the work focusses on modeling the performance of a scroll expander using two non-dimensionless parameters, namely, specific speed and specific diameter. Performance of a scroll …

Effects Of Support Fluid Type On Concrete Integrity And Durability In Drilled Shafts, Sarah J. Mobley

USF Tampa Graduate Theses and Dissertations

Until recently, concrete flow in tremie-placed drilled shafts has been mischaracterized as rising uniformly with laitance formation occurring only at the top of the rising concrete in the shaft. In actuality, concrete first fills a portion of the reinforcement cage to a sufficient height to promote radial flow into the cover region. Depending on support fluid type, the radial flow can produce laitance-filled creases/channels projecting the reinforcing cage configuration to the side of shaft surface. The flow pattern (and creases) can affect filter cake thickness, cover quality and propensity for corrosion. This research examines 52 tremie-placed laboratory drilled shaft specimens …

Study Of Transition Metal Dichalcogenides Via Linear And Non-Linear Spectroscopy, Christopher E. Stevens

USF Tampa Graduate Theses and Dissertations

Beginning with the discovery of graphene, two-dimensional materials have amassed a strong interest. Like graphene, transition metal dichalcogenides (TMDs) can be coaxed into atomically thin sheets which have some impressive properties. Unlike graphene, TMDs also has a change in their electronic band structure causing an indirect band gap to a direct gap transition in its monolayer form. Additionally, these materials lose their inversion symmetry as a monolayer. These unique properties make TMDs a strong candidate for being used in optoelectronic and valleytronic devices. In order for these devices to be successful, the optical properties of TMDs must be thoroughly understood. …

Longitudinal Analysis Of Perceived And Objective Airline Performance Quality, Kaetlyn Blocker, Javad Gorjidooz

Student Works

Commercial air carrier performance is a multivariable function, uniquely and substantially impacted by passenger's perception of negative employee behavior. High industry visibility, coupled with exponential social media growth, has provided the incredible potential to either widen or narrow the perception-performance gap. The present research conducts a rare longitudinal evaluation of objective airline performance quality in contrast with consumer perceptions of perceived airline performance and the dynamic changes occurring therein. Additionally, the implications regarding air carriers facing both objective and perceived performance challenges, as well as implications for the industry as a whole, are discussed. Utilizing nearly 30 years of objective …

High Enthalpy Storage Thermoset Network With Giant Stress And Energy Output In Rubbery State And Associated Applications, Jizhou Fan

LSU Doctoral Dissertations

In this study, a new shape memory thermoset network with giant stress and energy output in rubbery state is synthesized and studied firstly since the low output in stress and energy in rubbery state has been a bottleneck for wide-spread applications of thermoset shape memory polymers (SMPs). Traditionally, stress or energy storage in thermoset network is through entropy reduction by mechanical deformation or programming. We here report another mechanism for energy storage, which stores energy primarily through enthalpy increase by stretched bonds during programming. As compared to entropy-driven counterparts, which usually have a stable recovery stress from tenths to several …

Sodium-Ion Concentration Flow Cell Stacks For Salinity Gradient Energy Recovery: Power Generation Of Series And Parallel Configurations, Elizabeth Whiddon

LSU Master's Theses

Salinity gradient (SG) energy is a renewable and clean energy resource that exists worldwide from the change in Gibbs free energy when two solutions with different salinities are mixed. More recently, concentration flow cells (CFCs) have been introduced as a new technology for SG energy recovery with the highest reported power density output to date, as a result of the utilization of both the electrode potential and Donnan potential. In this study, multiple CFCs were connected to form a consecutive number of stacks, and systematic analysis was conducted to investigate the influence of both parallel and series electrical wire connections …

Reliability Of Corroding Reinforced Concrete Structures, Travis Honore

LSU Master's Theses

The enhanced performance due to the addition of steel within concrete elements has thrust reinforced concrete structures to be one of the most commonly used construction materials in the world. Reinforced concrete structures are exposed to a variety of deterioration mechanisms during their operational existence, each of which contributes to reducing their service life, durability, and load bearing capacity. The longevity of these reinforced concrete structures is strongly connected to degradation processes, whose origin is environmental and/or functional. Among these processes is the initiation and evolution of corrosion on the steel reinforcement. Steel reinforcement has direct effects on the durability, …

Teaching Top-Down Approaches To The Engineering Design Process, Joshua E. Katz, Joshua E. Katz

STAR Program Research Presentations

One of the main focuses of metacognition is to have students think about their learning. By bringing the engineering design process with educational psychology together, it can lead to a society that thinks more in-depth on various topics. The goal of the internship was to utilize and teach top-down educational and instructional objectives. Throughout the project, we followed a modified progression of the System Architecture Methodology to help other interns think in a top-down fashion. The purpose of this procedure is to create and induce new innovative and creative ideas for different projects. As teaching this methodology was tasked, research …

A Half-Yearly Newsletter Of The Department Of Mechatronics V2 S1 [July 2019], Chandrashekhar Bhat

Faculty work

No abstract provided.

A Half- Yearly E-Newsletter Of The Department Of Computer Science And Engineering, Manipal Institute Of Technology - Jul 2019, Ashalatha Nayak

Faculty work

No abstract provided.

Forecasting In Blockchain-Based Local Energy Markets, Michael Kostmann, Wolfgang Karl Hardle

Sim Kee Boon Institute for Financial Economics

Increasingly volatile and distributed energy production challenges traditional mechanisms to manage grid loads and price energy. Local energy markets (LEMs) may be a response to those challenges as they can balance energy production and consumption locally and may lower energy costs for consumers. Blockchain-based LEMs provide a decentralized market to local energy consumer and prosumers. They implement a market mechanism in the form of a smart contract without the need for a central authority coordinating the market. Recently proposed blockchain-based LEMs use auction designs to match future demand and supply. Thus, such blockchain-based LEMs rely on accurate short-term forecasts of …

Seven Hci Grand Challenges, Constantine Stephanidis, Gavriel Salvendy, Margherita Antona, Jessie Chen, Jianming Dong, Vincent Duffy, Xiaowen Fang, Cali Fidopiastis, Gino Fragomeni, Limin Fu, Yinni Guo, Don Harris, Andri Ioannou, Kyeong-Ah (Kate) Jeong, Shin'ichi Konomi, Heidi Kromker, Masaaki Kurosu, James Lewis, Aaron Marcus, Gabriele Meiselwitz, Abbas Moallem, Hirohiko Mori, Fiona Fui-Hoon Nah, Stavroula Ntoa, Pei-Luen Rau, Dylan Schmorrow, Keng Siau, Norbert Streitz, Wentao Wang, Sakae Yamamoto, Panayiotis Zaphiris, Jia Zhou

Faculty Publications

This article aims to investigate the Grand Challenges which arise in the current and emerging landscape of rapid technological evolution towards more intelligent interactive technologies, coupled with increased and widened societal needs, as well as individual and collective expectations that HCI, as a discipline, is called upon to address. A perspective oriented to humane and social values is adopted, formulating the challenges in terms of the impact of emerging intelligent interactive technologies on human life both at the individual and societal levels. Seven Grand Challenges are identified and presented in this article: Human-Technology Symbiosis; Human-Environment Interactions; Ethics, Privacy and Security; …

Santa Clara Magazine, Volume 60 Number 4, Summer 2019, Santa Clara University

Santa Clara Magazine

16 - PROTECTING THE HEART To grow the campus, we must care for the thing unchanging at its center—its Mission. Take a journey through the restoration of Mission Santa Clara de Asís. By Lander Eicholzer ’19.

22 - A LOBBY FOR JUSTICE What do you do when it is impossible for the innocent to prove their innocence? Change the law. The Northern California Innocence Project teamed up with state lawmakers and others to do just that. By Deborah Lohse.

26 - FINDING CENTER Outgoing Frank Sinatra Chair in the Performing Arts Taye Diggs reflects on celebrating who are you, where …