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Articles 169921 - 169950 of 198087
Full-Text Articles in Engineering
Introduction To Industrial Engineering: Interpretation Of Visual Displays, Paul Savory
Introduction To Industrial Engineering: Interpretation Of Visual Displays, Paul Savory
Department of Industrial and Management Systems Engineering: Instructional Materials
Classroom exercise for IMSE 150 at the University of Nebraska-Lincoln. This goal is to introduce freshman industrial engineering students to various aspects of industrial engineering and being an engineer. The area of human factors or ergonomics focuses on human beings and their interaction with products, equipment, facilities, producers, and environments used in work and everyday life. The emphasis is on human beings and how the design of things influences people. One small area of ergonomics is concerned with how humans interpret visual displays. For an introduction to this area, let's consider the visual interpretation of static displays (i.e., information that …
From Interval Methods Of Representing Uncertainty To A General Description Of Uncertainty, Vladik Kreinovich, Scott Ferson, Lev Ginzburg, Harry Schulte, Matthew R. Barry, Hung T. Nguyen
From Interval Methods Of Representing Uncertainty To A General Description Of Uncertainty, Vladik Kreinovich, Scott Ferson, Lev Ginzburg, Harry Schulte, Matthew R. Barry, Hung T. Nguyen
Departmental Technical Reports (CS)
Measurements do not result in an exact value of the measured quantity; even after the most accurate measurement, there is still some uncertainty about the actual value of the measured quantity. Traditionally, in science and engineering, this uncertainty is characterized by a probability distribution; however, often, we do not know this probability distribution exactly. So, to get a more adequate description of this uncertainty, we must consider classes of possible probability distributions. A natural question is: Are all possible classes needed for this description? In this paper, we show that even for simple situations, we indeed need arbitrary closed convex …
On Combining Statistical And Fuzzy Techniques: Detection Of Business Cycles From Uncertain Data, Hung T. Nguyen, Berlin Wu, Vladik Kreinovich
On Combining Statistical And Fuzzy Techniques: Detection Of Business Cycles From Uncertain Data, Hung T. Nguyen, Berlin Wu, Vladik Kreinovich
Departmental Technical Reports (CS)
Detecting the beginning and the end of the business cycle is an important and difficult economic problem. One of the reasons why this problem is difficult is that for each year, we have only expert estimates (subjective probabilities) indicating to what extent the economy was in growth or recession. In our previous papers, we used fuzzy techniques to process this uncertain information; namely, we used the operation min(a,b) to combine the subjective probabilities (expert estimates) of two events into a probability that both events happen. This function corresponds to the most optimistic estimate of the joint probability. In this paper, …
General Aviation Aircraft: A Comparative Analysis Of Analog Instrument Display And Conceptual Primary Flight Display, Ungul Laptaned
General Aviation Aircraft: A Comparative Analysis Of Analog Instrument Display And Conceptual Primary Flight Display, Ungul Laptaned
Master's Theses - Daytona Beach
The primary purpose of this study was to evaluate the effects that analog instrument display versus primary flight display (PFD) had on pilot performance. Pilot performance was evaluated by: (a) time, and (b) number of errors. There were twenty subjects with a minimum of a private pilot license selected from the Aeronautical Science department at Embry-Riddle Aeronautical University. Three flight conditions (spoiler problem, engine problem, and flap failure) acting as a control group was given to the flight students while flying a traffic pattern. A Silicon Graphics® flight simulation software program and a video camera were used as the data …
1999 Scholars And Artists Bibliography, Michael Schwartz Library, Cleveland State University, Friends Of The Michael Schwartz Library
1999 Scholars And Artists Bibliography, Michael Schwartz Library, Cleveland State University, Friends Of The Michael Schwartz Library
Scholars and Artists Bibliographies
This bibliography was created for the annual Friends of the Michael Schwartz Library Scholars and Artists Reception, recognizing scholarly and creative achievements of Cleveland State University faculty, staff and emeriti
Metadata In A Digital Special Library: The Energy And Environmental Information Resources Center In Lafayette, Louisiana, Dan Foley
E-JASL: Electronic Journal of Academic and Special Librarianship (1999-2009, Volumes 1-10)
This paper discusses three kinds of metadata and how they are used in the Energy & Environmental Information Resources Center (EE-IR Center), a digital special library of text, numeric, and geospatial data, located in Lafayette, Louisiana. These metadata are Dublin Core (DC), MARC21 (formerly USMARC), and Federal Geographic Data Committee (FGDC) metadata.
The EE-IR Center was formed as a partnership between the National Wetlands Research Center (NWRC) of the U.S. Geological Survey and the Center for Advanced Computer Studies of the University of Southwestern Louisiana (CACS/USL). Both partners are located in Lafayette, Louisiana. The EE-IR Center is funded by a …
Inspec On Firstsearch: An Evaluation And Tutorial For Effective Searching, Lutishoor Salisbury, Usha Gupta
Inspec On Firstsearch: An Evaluation And Tutorial For Effective Searching, Lutishoor Salisbury, Usha Gupta
E-JASL: Electronic Journal of Academic and Special Librarianship (1999-2009, Volumes 1-10)
This paper focuses on providing critical evaluation and searching tips for users of the INSPEC database on FirstSearch on the Web. It introduces the idea of records and fields, fields searching to focus a search for effective retrieval, and the use of the Related Headings feature. Also explained is the idea of precision searching using the proximity operators and bound-phrase searching capabilities. Other ways to search for specific types of information (for example, foreign names, reviews, theses and dissertations, and chemical searching) are also presented. We provide practical examples to illustrate the search features using the Basic, Advanced, and Command …
The Impact Of The Simulated Digital Data Radio Communication Induced Interference On Voice Radio Communication, Daniela T. Kratchounova
The Impact Of The Simulated Digital Data Radio Communication Induced Interference On Voice Radio Communication, Daniela T. Kratchounova
Master's Theses - Daytona Beach
The transition of air/ground communications, from its present analog structure to a new digital communications architecture, will span a 10-year time frame. Testing to date indicates that the potential for interference from the digital system to the analog system would be critical, especially for General Aviation (GA) aircraft. This type of interference can be described as short, random bursts of noise capable of completely obliterating parts of the voice communication. The subsequent degrading effects on voice radio communications could jeopardize flight safety. The masking of parts of important information would result in distracted attention, debilitated cognitive performance, high level of …
An Intermittent-Combustion General Aviation Aircraft Engine Exhaust Noise Prediction Algorithm, Hiroko Tada
An Intermittent-Combustion General Aviation Aircraft Engine Exhaust Noise Prediction Algorithm, Hiroko Tada
Master's Theses - Daytona Beach
From an environmental point of view, the reduction of aircraft noise has become an important factor recently. There are two factors that make airplane noise: propeller noise and engine noise. This report puts emphasis on only the engine noise in order to begin understanding what airplane engine exhaust noise is. At first, the engine exhaust noise is comprehended using the Dobrzynski's engine noise theory. Next, a discussion about an Embry-Riddle Aeronautical University (ERAU) engine system, engine exhaust system configurations, and microphone setting standards that show the ERAU engine system exhaust noise data. Finally, an Intermittent-Combustion (IC) General Aviation (GA) aircraft …
Introduction To Industrial Engineering: Operations Research, Paul Savory
Introduction To Industrial Engineering: Operations Research, Paul Savory
Department of Industrial and Management Systems Engineering: Instructional Materials
Classroom exercise for IMSE 150 at the University of Nebraska-Lincoln. This goal is to introduce freshman industrial engineering students to various aspects of industrial engineering and being an engineer. Operations Research is an area of industrial engineering concerned with the allocation of scarce resources. One area of operations research is linear programming. Linear programming is a method often used to solve large, complicated problems. These problems often require a manager to determine how to use the company’s limited resources most efficiently.
Introduction To Industrial Engineering: Simulation Analysis, Paul Savory
Introduction To Industrial Engineering: Simulation Analysis, Paul Savory
Department of Industrial and Management Systems Engineering: Instructional Materials
Classroom exercise for IMSE 150 at the University of Nebraska-Lincoln. This goal is to introduce freshman industrial engineering students to various aspects of industrial engineering and being an engineer. Simulation is one of industry’s most used operations research. Its uses range from answering questions about work-in-process and production feasibility to comparing alternative plans for system routing and scheduling.
Introduction To Industrial Engineering: Manufacturing Variability, Paul Savory
Introduction To Industrial Engineering: Manufacturing Variability, Paul Savory
Department of Industrial and Management Systems Engineering: Instructional Materials
Classroom exercise for IMSE 150 at the University of Nebraska-Lincoln. This goal is to introduce freshman industrial engineering students to various aspects of industrial engineering and being an engineer. This fun and interactive penny manufacturing game highlights the impact of variability, capacity, and overtime.
Introduction To Industrial Engineering: Ethical Choices, Paul Savory
Introduction To Industrial Engineering: Ethical Choices, Paul Savory
Department of Industrial and Management Systems Engineering: Instructional Materials
Classroom exercise for IMSE 150 at the University of Nebraska-Lincoln. This goal is to introduce freshman industrial engineering students to various aspects of industrial engineering and being an engineer. All industrial engineering, product designers, and managers must at some point in their career face an issue that requires some amount of ethical or moral judgment. Consider the following scenarios and discuss with your group members what each of you would do.
A Thin-Film Micromanufactured Oxygen Microelectrode, James Clay Mcguyer Jr.
A Thin-Film Micromanufactured Oxygen Microelectrode, James Clay Mcguyer Jr.
Doctoral Dissertations
The methods for production of recessed oxygen microelectrodes developed by Whalen, et al. (1967) and improved upon by Linsenmeier, et al. (1987) are dated production methods by the standards of sensor production of the current time. The production process for this type of polarographic oxygen sensing electrode has remained unchanged for over 10 years, and is a time consuming, extremely low-yield process. The goal of this project has been to use the techniques of micromanufacturing available at the Institute for Micromanufacturing at Louisiana Tech University to construct a recessed oxygen microelectrode with a batch process that has higher yield than …
Reactive Infiltration Of Silicon Melt Through Microporous Amorphous Carbon Preforms, P. Sangsuwan, Surendra N. Tewari, Jorge E. Gatica, M. Singh, R. Dickerson
Reactive Infiltration Of Silicon Melt Through Microporous Amorphous Carbon Preforms, P. Sangsuwan, Surendra N. Tewari, Jorge E. Gatica, M. Singh, R. Dickerson
Chemical & Biomedical Engineering Faculty Publications
The kinetics of unidirectional capillary infiltration of silicon melt into microporous carbon preforms has been investigated as a function of the pore morphology and melt temperature. The infiltrated specimens showed alternating bands of dark and bright regions, which corresponded to the unreacted free carbon and free silicon regions, respectively. The decrease in the infiltration front velocity for increasing infiltration distances is in qualitative agreement with the closed-form solution of capillarity-driven fluid flow through constant-cross-section cylindrical pores. However, drastic changes in the thermal response and infiltration front morphologies were observed for minute differences in the preform's microstructure. This suggests the need …
Toward Designing The Optimal Total Cavopulmonary Connection: An In Vitro Study, Ann E. Ensley, Patricia Lynch, George P. Chatzimavroudis, Carol Lucas, Shiva Sharma, Ajit P. Yoganathan
Toward Designing The Optimal Total Cavopulmonary Connection: An In Vitro Study, Ann E. Ensley, Patricia Lynch, George P. Chatzimavroudis, Carol Lucas, Shiva Sharma, Ajit P. Yoganathan
Chemical & Biomedical Engineering Faculty Publications
Background. Understanding the total cavopulmonary connection (TCPC) hemodynamics may lead to improved surgical procedures which result in a more efficient modified circulation. Reduced energy loss will translate to less work for the single ventricle and although univentricular physiology is complex, this improvement could contribute to improved postoperative outcomes. Therefore to conserve energy, one surgical goal is optimization of the TCPC geometry. In line with this goal, this study investigated whether addition of caval curvature or flaring at the connection conserves energy.
Methods. TCPC models were made varying the curvature of the caval inlet or by flaring the anastomosis. …
Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 15, Number 8, October 1999, College Of Engineering And Computer Science, Wright State University
Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 15, Number 8, October 1999, College Of Engineering And Computer Science, Wright State University
BITs and PCs Newsletter
A twelve page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.
Application Of A Fiber-Reinforced Continuum Theory To Multiple Deformations Of The Annulus Fibrosus, Stephen M. Klisch, Jeffrey C. Lotz
Application Of A Fiber-Reinforced Continuum Theory To Multiple Deformations Of The Annulus Fibrosus, Stephen M. Klisch, Jeffrey C. Lotz
Mechanical Engineering
Accurate tissue stress predictions for the annulus fibrosus are essential for understanding the factors that cause or contribute to disc degeneration and mechanical failure. Current computational models used to predict in vivo disc stresses utilize material laws for annular tissue that are not rigorously validated against experimental data. Consequently, predictions of disc stress resulting from physical activities may be inaccurate and therefore unreliable as a basis for defining mechanical–biologic injury criteria. To address this need we present a model for the annulus as an isotropic ground substance reinforced with two families of collagen fibers, and an approach for determining the …
Phase Structures And Morphologies Determined By Competitions Among Self-Organization, Crystallization, And Vitrification In A Disordered Poly(Ethylene Oxide)-B-Polystyrene Diblock Copolymer, Lei Zhu, Yan Chen, Anqui-Q. Zhang, Bret. H. Calhoun, Moonseok Chun, Stephen Z. D. Cheng, Benjamin S. Hsiao, Fengji Yeh, Takeji Hashimoto
Phase Structures And Morphologies Determined By Competitions Among Self-Organization, Crystallization, And Vitrification In A Disordered Poly(Ethylene Oxide)-B-Polystyrene Diblock Copolymer, Lei Zhu, Yan Chen, Anqui-Q. Zhang, Bret. H. Calhoun, Moonseok Chun, Stephen Z. D. Cheng, Benjamin S. Hsiao, Fengji Yeh, Takeji Hashimoto
College of Polymer Science and Polymer Engineering
A poly(ethylene oxide)-b-polystyrene (PEO-b-PS) diblock copolymer having a number-average molecular weight ((M) over bar(n)) of 11000 g/mol in the PEO blocks and an (M) over bar(n) of 5200 g/mol in the PS blocks has been synthesized (with a volume fraction of the PEO blocks of 0.66 in the molten state). Differential scanning calorimetry results show that this copolymer possesses a single endotherm, which is attributed to the melting of the PEG-block crystals. Based on real-time resolved synchrotron small-angle x-ray scattering (SAXS) observations, the diblock copolymer is in a disordered state above the glass transition temperature of the PS-rich phase (T-g(PS)) …
Rhythmic Growth Of Target And Spiral Spherulites Of Crystalline Polymer Blends, Thein Kyu, Hw Chiu, Aj Guenthner, Y Okabe, H Saito, T Inoue
Rhythmic Growth Of Target And Spiral Spherulites Of Crystalline Polymer Blends, Thein Kyu, Hw Chiu, Aj Guenthner, Y Okabe, H Saito, T Inoue
College of Polymer Science and Polymer Engineering
Numerical calculations reveal that the target and spiral growth patterns in spherulites can be generated from the time-dependent Ginzburg-Landau equations (model C) by coupling a conserved compositional order parameter and a nonconserved crystal ordering parameter. Of particular interest is that the periodic concentric rings (target) or the spirals at the spherulitic core remain stationary in both the crystal (orientational) ordering field and the concentration field. Another intriguing observation is that the growth of target and spiral spherulites occurs in a stepwise fashion in synchronism with the rhythmic energy dissipation during crystallization.
Theory Of Photon Coincidence Statistics In Photon-Correlated Beams, Majeed M. Hayat, Sergio N. Torres, Leno M. Pedrotti
Theory Of Photon Coincidence Statistics In Photon-Correlated Beams, Majeed M. Hayat, Sergio N. Torres, Leno M. Pedrotti
Electrical and Computer Engineering Faculty Research and Publications
The statistics of photon coincidence counting in photon-correlated beams is thoroughly investigated considering the effect of the finite coincidence resolving time. The correlated beams are assumed to be generated using parametric downconversion, and the photon streams in the correlated beams are modeled by two partially correlated Poisson point processes. An exact expression for the mean rate of coincidence registration is developed using techniques from renewal theory. It is shown that the use of the traditional approximate rate, in certain situations, leads to the overestimation of the actual rate. The error between the exact and approximate coincidence rates increases as the …
Darpa Mems Demonstration In Systems Of Dod Relevance, Robert J. Twiggs
Darpa Mems Demonstration In Systems Of Dod Relevance, Robert J. Twiggs
Robert "Bob" Twiggs STEM Education Collection
A PowerPoint Presentation created by Professor Bob Twiggs titled "DARPA MEMS Demonstration in Systems of DoD Relevance" from October of 1999.
Supervisory Control And Data Acquisition Experiment Using The Advanced Communications Technology Satellite, Florida Solar Energy Center, Carol Emrich
Supervisory Control And Data Acquisition Experiment Using The Advanced Communications Technology Satellite, Florida Solar Energy Center, Carol Emrich
FSEC Energy Research Center®
Satellite Supervisory Control and Data Acquisition (SCADA) was tested using the Advanced Communication Technology Satellite (ACTS) Ka-band signal and Ultra Small Aperture Terminal (USAT) ground stations. The SCADA system included a photovoltaic (PV)/diesel hybrid power generator designed to provide electricity to a rural community in a developing country. End-to-end baseline hardware checkout experiments have been completed. Results show that continuous two-second data transfers for real time monitoring can be completed with an error rate of less than 1%. The system recovers from simulated perturbations quickly and gracefully. Specifically, normal operation is resumed within 36 seconds following loss of power to …
Effect Of Interfacial Mobility On Flexural Strength And Fracture Toughness Of Glass/Epoxy Laminates, T. W. H. Wang, Frank D. Blum, Lokeswarappa R. Dharani
Effect Of Interfacial Mobility On Flexural Strength And Fracture Toughness Of Glass/Epoxy Laminates, T. W. H. Wang, Frank D. Blum, Lokeswarappa R. Dharani
Chemistry Faculty Research & Creative Works
Mechanical testing and surface fractography were used to characterize the fracture of E-glass fiber reinforced epoxy composites as a function of the silane coupling agent used. gamma-Aminopropyltriethoxysilane (APS) and delta-aminobutyltriethoxysilane (ABS) were used because these have been shown to have different interfacial mobilities at multilayer coverage. The values of the properties studied generally increased from untreated c, as determined from a Mode I translaminar fracture toughness tests, for the untreated composites (10.5 ± 0.4 kJ/m2) was lower than that for the ABS-treated composites (14.3 ± 2.1 kJ/m2) which was lower than that for the APS-treated composites (17.1 ± 2.4 kJ/m2). …
The Internet Name Game And The Nonprofit Solution, Roger A. Lohmann
The Internet Name Game And The Nonprofit Solution, Roger A. Lohmann
Faculty & Staff Scholarship
This paper is a case study of the campaign to create a new internet names authority to handle the assignment of internet domain names. Almost everyone knows by now that the Internet was originally a defense research project, which morphed into a research network for scientists and then into a tool of higher education and eventually into the commercial and general household utility we know today. In terms familiar to nonprofit research community what began in the state sector, expanded into the third sector and then into the market and household sectors and the consumer economy. There is a second …
The Microchannel Flow Of A Micropolar Fluid, Guohua Liu
The Microchannel Flow Of A Micropolar Fluid, Guohua Liu
Doctoral Dissertations
Micro-channel flows have been computed to investigate the influence of Navier-Stokes formulation for the slip-flow boundary condition, and a micro-polar fluid model, respectively.
The results of the slip boundary condition show that the current methodology is valid for slip-flow regime (i.e., for values of Knudsen number less than approximately 0.1). Drag reduction phenomena apparent in some micro-channels can be explained by slip-flow theory. These results are in agreement with some computations and experiments.
An ad hoc micro-polar fluid model is developed to investigate the influence of micro effects, such as micro-gyration, in micro-scale flows. The foundation of the ad hoc …
Suppression Of Post-Buckling Deflection And Panel-Flutter Using Shape Memory Alloy, Mohammad Tawfik Abo El So-Oud
Suppression Of Post-Buckling Deflection And Panel-Flutter Using Shape Memory Alloy, Mohammad Tawfik Abo El So-Oud
Mechanical & Aerospace Engineering Theses & Dissertations
A novel concept proposed is the use of Shape Memory Alloy (SMA) to reduce the panel thermal deflection and flutter responses. SMA has unique ability to recover large prestrains completely when the alloy is heated (by aerodynamic heating in the present case) above the austenite start temperature As. During the recovery process, a large tensile recovery stress occurs if the SMA is restrained.
In this thesis, a panel subject to the combined aerodynamic and thermal loading is investigated. A nonlinear finite element model based on von Karman strain displacement relation is utilized to study the effectiveness of SMA …
An Improved Thermal Mass Flow Controller For Hazardous And Precision Applications, William J. Alvesteffer
An Improved Thermal Mass Flow Controller For Hazardous And Precision Applications, William J. Alvesteffer
Mechanical & Aerospace Engineering Theses & Dissertations
A new mass flow controller has been designed which responds very rapidly to changes in control settings. The design was evolved after carefully studying the internal flow and the sources for thermal lag and other non-linear behavior. After discussing an overview of the basic mass flow controller operating principles, data will be presented which characterize the basic building blocks of an advanced flow sensor design. Subsequently, a flow model and control strategy have been developed and tested which reduce response lag significantly. Results of the new design, obtained experimentally under various transient conditions, will be discussed.
Long-Term Aircraft Structural Integrity Prediction Under The Influence Of Feedback Control, Si-Bok Yu
Long-Term Aircraft Structural Integrity Prediction Under The Influence Of Feedback Control, Si-Bok Yu
Mechanical & Aerospace Engineering Theses & Dissertations
This thesis investigates the influence of feedback control, and other factors associated with loading characteristics, on fatigue damage reduction and long-term integrity of aircraft structural components. An actively controlled flexible aircraft model and a new state space modeling procedure for crack growth are utilized to uncover important factors which influence airframe crack growth. A matrix of simulation test cases is constructed to cover such variables as open-loop operation, nominal closed-loop operation, perturbed closed-loop operation (i.e., feedback gain variation), nominal maneuver profile, perturbed maneuver profile (including overload strength and frequency), atmospheric gust, and mean stress level. Simulation output data including crack …