Engineering Commons^™

Controlled Rest In Position (Crip): Consumer Perceptions In The United States, Scott R. Winter, Jason Carryl, Stephen Rice

Publications

Controlled rest in position (CRIP) has been suggested as a viable countermeasure to the Federal Aviation Administration (FAA) in the ongoing efforts to combat in-flight pilot fatigue. It is already in use in other parts of the world; however, it is not currently permitted in the United States. While expert opinion suggested it poses little threat to flight safety, with valuable returns in terms of improved crew alertness and performance, there is some doubt about the level of consumer buy-in. This study completed a preliminary investigation into overall consumer willingness to fly, in the use of CRIP procedures in the …

Organizational Learning In Commercial Construction: Lessons Learned From The 2007-2009 U.S. Recession, Evan Michael Danforth

Theses and Dissertations

Organizational learning seeks to proactively expand the knowledge base of an organizational entity by incorporating knowledge, skills, and experience into the collective conscience of the company through the development of routines rather than relying on individual employees for these traits. Valuable experience gained by individuals who weather economic downturn with their companies must be absorbed into the corporate structure in a meaningful way so that it may be accessible for use during future recessions. This research asks what was learned by individuals during the most recent recession, what mechanisms were employed to retain and utilize this knowledge, and what cultures, …

A Compliant Mechanism-Based Variable-Stiffness Joint, Jacob Marc Robinson

Theses and Dissertations

A review of current variable-stiffness actuators reveals a need for more simple, cost effective, and lightweight designs that can be easily incorporated into a variety of human-interactive robot platforms. This thesis considers the potential use of compliant mechanisms to improve the performance of variable-stiffness actuators. The advantages and disadvantages of various concepts using compliant mechanisms are outlined, along with ideas for further exploration. A new variable-stiffness actuator that uses a compliant flexure as the elastic element has been modeled, built, and tested. This new design involves a variable stiffness joint that makes use of a novel variable transmission. A prototype …

A Hybrid Controller For Stability Robustness, Performance Robustness, And Disturbance Attenuation Of A Maglev System, Feng Tian

Dissertations (1934 -)

Devices using magnetic levitation (maglev) offer the potential for friction-free, high-speed, and high-precision operation. Applications include frictionless bearings, high-speed ground transportation systems, wafer distribution systems, high-precision positioning stages, and vibration isolation tables. Maglev systems rely on feedback controllers to maintain stable levitation. Designing such feedback controllers is challenging since mathematically the electromagnetic force is nonlinear and there is no local minimum point on the levitating force function. As a result, maglev systems are open-loop unstable. Additionally, maglev systems experience disturbances and system parameter variations (uncertainties) during operation. A successful controller design for maglev system guarantees stability during levitating despite system …

Mechatronics Design Process With Energy Optimization For Industrial Machines, Aderiano Medeiros Da Silva

Dissertations (1934 -)

The need for designing industrial machines with higher energy efficiency, reliability, flexibility, and accuracy has increased to satisfy market demand for higher productivity at reduced costs in a sustainable manner. As machines become more complex, model-based design is essential to overcome the challenges in mechatronic system design. However, a well-designed mechanical system with a well-designed and tuned control system are not sufficient for machines to operate at high-performance conditions; this also heavily depends on trajectory planning and the appropriate selection of the motors controlling the axes of the machine. In this work, a model-based design approach to properly select motors …

Dynamic Modeling Of Human Gait Using A Model Predictive Control Approach, Jinming Sun

Dissertations (1934 -)

This dissertation aims to develop a dynamic model of human gait, especially the working principle of the central nervous system (CNS), using a novel predictive approach. Based on daily experience, it should be straightforward to understand the CNS controls human gait based on predictive control. However, a thorough human gait model using the predictive approach have not yet been explored. This dissertation aims to fill this gap. The development of such a predictive model can assist the developing of lower limb prostheses and orthoses which typically follows a trial and error approach. With the development of the predictive model, lower …

Detect And Avoid For Small Unmanned Aircraft Systems Using Ads-B, Timothy Mclain, Laith R. Sahawneh, Matthew O. Duffield, Randall W. Beard

Faculty Publications

With the increasing demand to integrate unmanned aircraft systems (UAS) into the National Airspace System (NAS), new procedures and technologies are necessary to ensure safe airspace operations and minimize the impact of UAS on current airspace users. Currently, small UAS face limitations on their use in civil airspace because they lack the ability to detect and avoid other aircraft. This article presents a framework that consists of an Automatic Dependent Surveillance-Broadcast (ADS-B)-based sensor, track estimator, conflict/collision detection, and resolution that mitigates collision risk. ADS-B offers long-range, omni-directional intruder detection with comparatively few size, weight, power, and cost demands. The proposed …

Generation Of Multi-Charged Aluminum Ions From Femtosecond Laser Induced Plasma, Frederick Guy Wilson

Electrical & Computer Engineering Theses & Dissertations

Laser-induced plasma multi-charged ion (MCI) sources have gained in popularity over the last thirty years with the advent of reliable, high peak power, short temporal pulse laser systems. Utilization of laser-induced plasma MCI sources allows for production of a wide array of ion species from a variety of source target materials. In this thesis an investigation of the generation of MCis from an aluminum (Al) target source through laser-induced plasma from a femtosecond (fs) pulsed laser system is outlined and the results presented and analyzed. In order to characterize the production of the Al MCis resulting from the fs laser …

Cardiovascular Magnetic Resonance Imaging-Based Computational Fluid Dynamics/Fluid-Structure Interaction Pilot Study To Detect Early Vascular Changes In Pediatric Patients With Type 1 Diabetes, Margaret M. Samyn, Ronak Jashwant Dholakia, Hongfeng Wang, Jennifer Co-Vu, Ke Yan, Michael E. Widlansky, John F. Ladisa Jr., Pippa Simpson, Ramin Alemzadeh

Biomedical Engineering Faculty Research and Publications

We hypothesized that pediatric patients with type 1 diabetes have cardiac magnetic resonance (CMR) detectable differences in thoracic aortic wall properties and hemodynamics leading to significant local differences in indices of wall shear stress, when compared with age-matched control subjects without diabetes. Pediatric patients with type 1 diabetes were recruited from Children’s Hospital of Wisconsin and compared with controls. All underwent morning CMR scanning, 4-limb blood pressure, brachial artery reactivity testing, and venipuncture. Patient-specific computational fluid dynamics modeling with fluid–structure interaction, based on CMR data, determined regional time-averaged wall shear stress (TAWSS) and oscillatory shear index (OSI). Twenty type 1 …

Analyzing Driver Behavior And Traffic Flow Breakdowns At The Hampton Roads Bridge Tunnel, Michelle L. Allen

Civil & Environmental Engineering Theses & Dissertations

The Hampton Roads Bridge Tunnel (HRBT) is a major link for activity in Hampton Roads. The eastbound direction also suffers from congestion during both morning and peak hours. During these periods of congestion, the flow rate varies in regards to the location of the congestion. This study focuses on investigating driver behavior during these different conditions and briefly investigates the cost of delay due to the different capacities. To accomplish this, per vehicle record data (PVR) is used. This data, collected at the exit of the tunnel, provides information on arrival time, speed, lane location, vehicle class, and time headway. …

Development Of A Practical Visual-Evoked Potential-Based Brain-Computer Interface, Nicholas R. Waytowich

Biomedical Engineering Theses & Dissertations

There are many different neuromuscular disorders that disrupt the normal communication pathways between the brain and the rest of the body. These diseases often leave patients in a `locked-in" state, rendering them unable to communicate with their environment despite having cognitively normal brain function. Brain-computer interfaces (BCIs) are augmentative communication devices that establish a direct link between the brain and a computer. Visual evoked potential (VEP)- based BCIs, which are dependent upon the use of salient visual stimuli, are amongst the fastest BCIs available and provide the highest communication rates compared to other BCI modalities. However. the majority of research …

Development Of Superconducting Spoke Cavities For High-Velocity Applications, Christopher Shawn Hopper

Physics Theses & Dissertations

To date, superconducting spoke cavities have been designed, developed, and tested for particle velocities up to β0 ~ 0.6, but there is a growing interest in possible applications of spoke cavities for high-velocity applications. The first task is to explore the design parameter space for low-frequency, high-velocity, single- and double-spoke superconducting cavities in order to determine how each design parameter affects the electromagnetic properties, in particular the surface electromagnetic fields and the shunt impedance. Once an electromagnetically optimized, high-velocity spoke cavity is designed, there are several other characteristics that need to be investigated. These include multipacting scenarios, higher-order mode excitation …

Isogeometric Analysis For Electromagnetism, Tahsin Khajah

Mechanical & Aerospace Engineering Theses & Dissertations

The combination of numerical analysis with the scanning technology has been seeing increased use in many research areas. There is an emerging need for high-fidelity geometric modeling and meshing for practical applications. The Isogeometric Analysis (IGA) is a comprehensive computational framework, which integrates geometric modeling and meshing with analysis. Different from other existing numerical methods, the IGA can generate analysis ready models without loss of geometrical accuracy. In IGA, the continuity and the quality of a solution can be conveniently controlled and refined. These features enable IGA to integrate modeling, analysis, and design in a unified framework, the root idea …

An Analysis Of The Relationship Between Military Leaders' Operational Adaptability And Knowledge Transfer, Vahap Kavaker

Engineering Management & Systems Engineering Theses & Dissertations

A variety of research underlines the increasing need for adaptable leaders in the military and enhancing operational adaptability is accepted as one of the crucial factors for achieving success in future military operations. In general terms, operational adaptability is the ability to successfully respond to unforeseen changing situations during military operations. However, this study reveals that operational adaptability is not clearly conceptualized and supporting factors are not investigated in detail in the literature. Among possible factors, knowledge transfer is claimed to be an important practice that increases personal performance and effectiveness.

This research conceptualized operational adaptability and investigated the relationship …

Command And Control In The Information Age: A Case Study Of A Representative Air Power Command And Control Node, Marvin Leo Simpson Jr.

Engineering Management & Systems Engineering Theses & Dissertations

As operations command structures change, it is important to be able to explore and understand their fundamental nature; researchers should unearth the gestalt nature of the operational node. The organizational structure and the infrastructure can significantly affect overall command and control (C2) performance. Thus, it is necessary to develop understanding of effectiveness of the technical network and the people using the system as a whole.

The purpose of this research is to conduct an analysis of a representative Air Power Operational C2 node, create and use a repeatable method, and present the results as a case study to elicit fundamental …

Ablation Of Cardiac Tissue With Nanosecond Pulsed Electric Fields: Experiments And Numerical Simulations, Fei Xie

Biomedical Engineering Theses & Dissertations

Cardiac ablation for the treatment of cardiac arrhythmia is usually performed by heating tissue with radio-frequency (RF) electrical currents to create conduction-blocking lesions in order to stop the propagation of electrical waves. Problems associated with RF ablation are recurrence of arrhythmias after successful treatments, tissue loss beyond the targeted tissue, long duration of the ablation procedure, and thermal side effects including thrombus formation that may lead to stroke. Here, we propose a new, non-thermal ablation method using nanosecond pulsed electric fields (nsPEFs) with better-controlled ablation volume, shorter procedure time, and no thermal side effects. We demonstrate that we can create …

Toward A Theory Of Multi-Method Modeling And Simulation Approach, Mariusz A. Balaban

Computational Modeling & Simulation Engineering Theses & Dissertations

The representation via simulation models can easily lead to simulation models too simple for their intended purpose, or with too much detail, making them hard to understand. This problem is related to limitations of the modeling and simulation methods. A multi-method Modeling and Simulation (M&S) approach has the potential for improved representation by taking advantage of methods' strengths and mitigating their weaknesses. Despite a high appeal for using multiple M&S methods, several related problems should be addressed first. The current level of theoretical, methodological, and pragmatic knowledge related to a multi-method M&S approach is limited. It is problematic that there …

The Use Of Lanthanum (La+3) And Cerium (Ce+3) Ions As Phosphate Activators In Low Grade Phosphate Flotation, Salah Al-Thyabat, Patrick Zhang

Beneficiation of Phosphates VII

No abstract provided.

Application Of Custofloat® Carbonate Collectors In Beneficiating Phosphate Ores In China, Guoxin Wang, Zhengguo Jiang, Lingyi Du

Beneficiation of Phosphates VII

Custofloat® 813 (CF-813) is a collector specially designed and manufactured by ArrMazz for reverse flotation of phosphate ores with carbonate impurities. It was used to process phosphate ores from several mines in China with great success. The paper will present the process flowsheets and flotation results of phosphate ores in three commercial beneficiation plants.

Processing Florida Dolomitic Phosphate Pebble With Custofloat® Carbonate Collectors, Guoxin Wang, Zhengxing (James) Gu

Beneficiation of Phosphates VII

It was estimated that phosphate reserves associated with high carbonate minerals are greater than those with siliceous gangues worldwide. It has been long recognized that separation of carbonate from phosphate is difficult because those minerals contain same or similar alkaline earth cations which lead them to exhibit similar surface behavior in flotation. With the depletion of easy-to-process phosphate reserves, phosphate deposits with high carbonate impurities must be mined and processed to meet the demand. Crushing, grinding and flotation are considered the most efficient process to recover phosphate from phosphate ores associated with carbonate gangue minerals. Therefore, flotation reagents, especially collectors, …

An Examination Of The Potential For Distributed Wind Generation (Dwg) In Urban Distribution Networks, Keith Sunderland, Thomas Woolmington, Michael Conlon, Gerald Mills

Conference papers

In a sustainable economy, smarter cities need energy networks that can deliver consistent electricity while maximising the use of intermittent renewables. Therefore an understanding of the available resource and a means for viable integration of distributed generation (DG) is required. In this research, energy harvesting of the wind climate is considered in the context of distributed wind generation (DwG) as an integral component of a smarter electricity network. The approach combines wind climate modeling of the resource at the urban scale with enhanced electricity network simulation. The former considers energy harvesting potential while the latter investigates the opportunities for this …

Mainstreaming Green Infrastructure: The Nexus Of Infrastructure And Education Using The Green Space Based Learning (Gsbl) Approach For Bioretention Plant Selection, Ryan Charles Robert Locicero

USF Tampa Graduate Theses and Dissertations

The Green Space Based Learning (GSBL) approach builds on a long-term partnership between a Research I university, surrounding community, and local school district, transforming underutilized community green space into an interactive educational tool to addresses national infrastructure and educational challenges. The GSBL approach is an educational platform for engaging K-12 and the local community in engineering design and construction of sustainable Green Infrastructure (GI) projects. GSBL was piloted as a part of a federally funded Research Experience for Teachers (RET) program in which teachers participated in two intensive 6-week summer research experiences and two consecutive academic year components. The summer …

Recovery Of Ree From An Apatite Concentrate In The Nitrophosphate Process Of Fertilizer Production, Mahmood Alemrajabi, Kerstin Forsberg, Ake Rasmuson

Beneficiation of Phosphates VII

No abstract provided.

The Surface And Colloid Chemistry Of Layered Silicate Minerals, J.D. Miller, Jing Liu

Beneficiation of Phosphates VII

No abstract provided.

Upgrading Phosphate Flotation Tailings For Rare Earths Extraction, Salah Al-Thyabat, Patrick Zhang

Beneficiation of Phosphates VII

No abstract provided.

Pertumbuhan, Hasil Dan Kualitas Tomat Cv. Marta-9 Pada Berbagai Sistem Budidaya Dalam Rumah Plastik Di Dataran Medium Jatinangor, Tino Mutiarawati Onggo, Sumadi, R. Fauziah

Jurnal Kultivasi

Penanaman tomat dalam rumah plastik dengan sistem budidaya hidroponik, meng-0hasilkan buah dengan kuantitas dan kualitas baik serta dapat dilakukan secara kontinu, namun kekurangan sistem tersebut adalah bahan kimia yang digunakan untuk hara tanaman mahal, sehingga perlu dicarikan sistem budidaya alter-natif yang dapat mengimbangi hasil dan kualitas hasil sistem hidroponik. Tujuan dilaku-kannya penelitian ini adalah untuk mempelajari berbagai sistem budidaya tanaman tomat dalam rumah plastik yang dapat diaplikasikan di dataran medium dengan biaya yang lebih murah serta menguji jumlah batang produksi yang dapat menghasilkan pertumbuhan dan hasil tanaman serta kualitas tomat yang baik. Penelitian dilakukan dari bulan Juni sampai dengan Oktober …

How Engineering Teams Select Design Concepts: A View Through The Lens Of Creativity, Christine Toh, Scarlett Miller

Interdisciplinary Informatics Faculty Publications

While concept selection is recognized as a crucial component of the engineering design process, little is known about how concepts are selected during this process or what factors affect the selection of creative concepts. To fill this void, content analysis was performed on student engineering design team discussions during a concept selection task. Our results indicate that student design teams typically focus on the technical feasibility of concepts during the selection process. However, teams that identified useful elements of ideas or continued to generate new ideas during this process had a tendency towards selecting creative ideas. These results add to …

Bicyclist Compliance At Signalized Intersections, Samson Ray Riley Thompson

Dissertations and Theses

This project examined cyclist red light running behavior using two data sets. Previous studies of cyclist compliance have investigated the tendencies of cyclists to run red lights on the whole by generalizing different maneuvers to their end outcome, running a red light. This project differentiates between the different types of red light running and focuses on the most egregious case, gap acceptance, which is when a cyclist runs a red light by accepting a gap in opposing traffic.

Using video data, a mathematical model of cyclist red light running was developed for gap acceptance. Similar to other studies, this analysis …

Insights Into Ultrasonic Release From Eliposomes, Marjan Javadi, William G. Pitt

Faculty Publications

A novel nanosized liposomal carrier was prepared consisting of perfluorocarbon emulsion droplet(s) encapsulated inside a liposome, which is called an eLiposome. This 200-nm construct is useful for acoustically activated drug delivery because ultrasound causes the emulsion droplet to expand from liquid to gas, which expansion ruptures the eLiposome bilayer and releases the internal contents. This study focuses on the parameters that influence control of the release of calcein (a model drug), including ultrasound amplitude, insonation time, and perfluorocarbon vapor pressure as a function of temperature and composition. The results show that calcein release increases as the ultrasound amplitude or insonation …

Long-Term Metal Retention Performance Of Media Filter Drains For Stormwater Management, Agathe Thomas, Liv Haselbach, Cara Poor, Maxwell Freimund

Civil and Environmental Engineering Faculty Publications and Presentations

Stormwater runoff, a substantial source of nonpoint pollution, can be treated using Best Management Practices (BMPs), such as the Media Filter Drain (MFD). An MFD is a trench filled with an engineered media mix, usually with a grass overlay, that receives runoff from the paved roadway next to it. The MFD was shown to remove dissolved metals (zinc and copper), typical pollutants from vehicles and urban areas, which might negatively impact aquatic species in receiving waters, but its long-term effectiveness was not known. Existing media filter mixes of different ages were collected from two different sites in the Pacific Northwest …