Engineering Commons^™

Froth Flotation Apparatus, Jiann-Yang Hwang

Michigan Tech Patents

The froth flotation apparatus includes a gas bubble-particle contact unit including a mixing structure for breaking a gas into fine bubbles,such as a packed tower packing or mechanical agitator, and a separate phase separation unit. A conditioned aqueous pulp containing a mixture of hydrophobic and hydrophilic particles and a substantially inert gas, such as air, are introduced into and combined in one end of the contact unit and subsequently flow concurrently through the mixing structure, such that the gas is broken into fine bubbles which intimately contact and become attached to the hydro- phobic particles. The resulting gas bubble-particle mixture …

Statistical, Random And Fractal Characterizations Of Surface Topography With Engineering Applications, Gongyao Zhou

Dissertations

Two methods, namely the conventional and fractal geometry methods, are developed for surface topography characterization. The conventional method utilizing statistical and random process techniques is used to study waterjet machined surfaces. In the study the waterjet surfaces are separated into smooth and striation zones, where striation influence is negligible in the smooth zone. It is found that the smooth zone has a random, moderately isotropic texture, with the height distribution nearly Gaussian. In the striation zone the major frequencies of the surface profile power spectra are independent of cutting parameters, while the amplitudes of these frequencies monotonically increase with cutting …

Acuta Enews October 1993, Vol. 22, No. 10

ACUTA Newsletters

In This Issue

E-mail

President's message

Data Comm Project at Delaware Tech

User Groups Meet at Conference

21st Century Technology

Staff Report

Fal 1993, Wmpg 90.9 Fm

WMPG Program Guides

WMPG program guide for Fall 1993

Includes notes from Program Director, information on shows and events, and schedule.

Seismic Code Analysis Of Buildings Without Locating Centers Of Rigidity, Rakesh K. Goel, Anil K. Chopra

Civil and Environmental Engineering

Static force procedures of most building codes require that the lateral earthquake force at each floor level of an asymmetric-plan building be applied eccentrically from the centers of rigidity. To implement such procedures, it seemed necessary in the past to determine the locations of the centers of rigidity, an often confusing and cumbersome process. This paper presents a new approach for code lateral force analysis of asymmetric-plan buildings without locating the centers of rigidity. This procedure combines the results from three static analyses, which can be implemented directly on most commercially available computer programs for analysis of multistory buidings. The …

Bulletin - Fall, 1993, Civil Aviation Medical Association

Browse all Civil Aviation Medical Association Newsletters

A twelve page newsletter of the Civil Aviation Medical Association. The newsletter provided news about civil aviation medicine and information related to the organization.

Ole Miss Engineer 1993

Ole Miss Engineer

No abstract provided.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 9, Number 8, October 1993, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A ten page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Santa Clara Magazine, Volume 36 Number 1, Fall 1993, Santa Clara University

Santa Clara Magazine

10 - DISCONNECTED A loss of continuity and connectedness could be the price we pay for this era of decentralized, customized technology. By Timothy J. Lukes

14 - STRETCHED TO THE LIMIT Private colleges scramble to control financial aid costs, and families struggle with too few aid dollars to go around. Here are the stories of four families who have worked in partnership with the University to make it through. By Elizabeth Fernandez '79, Overview by Elise Banducci '87

23 - THE MORAL LIFE In his recent encyclical, the pope speaks out on human nature, Christian boundaries, and universal truths. …

Bs News

Building Services Engineering

No abstract provided.

Impulse, Cindy Maisch, Cindy Price, Samantha Penney, Julianne Trautmann

Impulse (Jerome J. Lohr College of Engineering Publication)

Features:
[Page 2] Mini-Baja Racing Team: Students create vehicle for Midwest contest
[Page 3] Contributors make it possible for Mini-Baja team to compete
[Page 4] SDSU dune buggy hits the track at Midwest Mini-Baja Competition
[Page 5] Inventors Congress enters second year
[Page 6] SkidMix: Ag engineering project shows strong manufacturing possibility
[Page 7] SDSU graduate student invents color machine vision
[Page 8] Helder develops procedure to improve readability of satellite data
[Page 9] Researchers, alumni create technology to help farmers

Departments:
FACULTY
[Page 10] Ground source heat pump research may lead to new training facility
[Page 11] Sander serves …

Two-Dimensional Simulation Of Switch-On Speeds In Hydrogenated Amorphous Silicon Thin-Film Transistors, J. S. Huang, Cheng-Hsiao Wu

Electrical and Computer Engineering Faculty Research & Creative Works

We report accurate two-dimensional simulations of switch-on speeds in hydrogenated amorphous silicon thin-film transistors. The trap charge density along, or transverse to, the direction of semiconductor channel is highly nonuniform and the trap filling time dominates the switching time as compared to the transit time, which is about four orders of magnitude smaller. Near both contacts, direction of the transverse current is always upwards toward the insulator-semiconductor interface due to the strong electric fields. However, at the central region of the channel, the transient current is quite complex and is discussed here. When the channel length varies from 2 to …

Coordinated Intelligent Control Via Epistemic Utility Theory, Wynn C. Stirling

Faculty Publications

An approach to local reactive coordinated intelligent control based on the concept of an epistemic system, together with a principle of action that may be exercised locally, is presented. An epistemic system provides a mechanism for agents to characterize their knowledge corpora, options, goals, and beliefs. Levi's rule of epistemic utility provides a principle of action for decision making by comparing the informational value of rejection with the belief of correctness. Decisions are made locally and reactively, rather than globally. Coordination is implemented between agents by sharing and learning the epistemic systems of other agents. The resulting coordination model is …

Emissions Studies For A Natural Gas-Fired Internal Combustion Engine, Carlos M. Buitrago

Mechanical & Aerospace Engineering Theses & Dissertations

Since 1991, a University owned truck has been operating with natural gas. In order to improve emissions performance a different fuel management strategy was developed. With the help of Siemens Automotive in Newport News, VA, a liquid fuel injector was modified to handle natural gas. The basic engine was tested to determine the benefits in emissions that the multi-point injection system can have over the single point injection system that had been used previously. Pre-catalyst, raw exhaust-gas data for the more important pollutants were taken and analyzed in both systems under different loads and intake manifold pressures. In addition, to …

Simulation Of Vertical Tail Buffet In Internal Vortex Breakdown Flows, Mark William Flanagan

Mechanical & Aerospace Engineering Theses & Dissertations

Computational simulation of vertical tail buffet in an internal vortex breakdown flow is considered. The fiuid-flow problem is formulated using the full, compressible, unsteady Navier-Stokes equations which are solved using an implicit, flux-difference splitting, finite volume scheme. The fluid-flow problem is solved in a configured circular duct using quasi-axisymmetric assumptions to simplify the flow equations. A plate is placed transverse to the incoming flow. Solution of the flow in the duct is performed with and without a rigid plate, and with and without an elastic plate. The elastic response of the plate is calculated assuming that it is a cantilever …

Accurate Evaluation Of Homogeneous And Nonhomogeneous Gas Emissivities, Kam-Pui Lee

Mechanical & Aerospace Engineering Theses & Dissertations

Spectral transmittance and total band absorptance of selected infrared bands of carbon dioxide and water vapor are calculated by using the line-by-line and quasi-random band models and these are compared with available experimental results to establish the validity of the quasi-random band model. Various wide-band model correlations (such as Edwards and Balakrishnan, Tien and Lowder, and Felske and Tien) are employed to calculate the total band absorptance and total emissivity of these two gases under homogeneous and nonhomogeneous conditions. These results are compared with available experimental results under identical conditions. From these comparisons. it is found that the quasi-random band …

A New Adjoint Variable Method For The Sensitivity Analysis Of Dynamic Responses, Krishnamoorthy Ramesh

Mechanical & Aerospace Engineering Theses & Dissertations

A new adjoint variable method has been formulated for finding the sensitivity derivatives of dynamic system responses. Though the method can be based on any step-by-step time marching scheme, the Wilson Theta Method has been chosen as the basis of the new formulation . Wilson Theta Method is an implicit numerical integration scheme for finding the dynamic system responses. The new formulation uses the differential form of equations of motion as given by the Wilson Theta Method in its formulation of the adjoint equation. The conventional methods used for finding the sensitivity derivatives, namely, the direct differentiation technique, the central …

Computation Of The Aerodynamic Characteristics Of A Subsonic Transport Aircraft Using A Panel Method, Lillianne Plaster Whitelock Troeger

Mechanical & Aerospace Engineering Theses & Dissertations

An advanced low-order panel method, VSAERO, is applied to a full-configuration transport aircraft. Wing pressure distributions as well as lift, drag, and pitching moment coefficients calculated for the full computational configuration are compared with experimental data. In addition, partial configurations are evaluated computationally to determine the relevance of certain complex aircraft components to the computations. It is shown that the wing-surface pressure distributions and pitching moment coefficient are well predicted by VSAERO. The lift coefficient is consistently overpredicted by the code.

An Evaluation Of The Implementation Of Total Quality Management In A Service Organization, Charles Stanford Stevens

Engineering Management & Systems Engineering Theses & Dissertations

This research consists of a formative evaluation designed to identify the steps necessary to revitalize a formerly successful Total Quality Management (TQM) process at a U.S. Navy engineering and logistics support organization. The research also developed a methodology to account for the fact that the investigator is a well-informed insider who served as one of the principle change agents for the TQM implementation.

The research is based on the researcher's observation that the major cause for the waning implementation was due to senior management and leadership issues and the organization-wide processes with which they interface. The investigation consisted of an …

Field Performance Report On Corrugated Polyethylene Pipe On Ky 17 Kenton County, L. John Fleckenstein, David L. Allen

Kentucky Transportation Center Research Report

This report documents the installation and performance of corrugated smooth lined polyethylene pipe installed during construction of KY 17 in Kenton County. The majority of the pipe installed was N-12 pipe manufactured by Advanced Drainage Systems, Inc., and is designated as ADS N-12. ADS N-12 is a corrugated high-density polyethylene (HDPE) pipe. The pipe has a corrugated exterior for increased strength and a smooth interior to provide maximum flow capacity.

Sags in grade, misalignment, poor coupling, and vertical deformation were observed during visual inspections and do not appear to be a material related problem but are largely due to poor …

Polymerization-Induced Phase-Separation In A Liquid-Crystal-Polymer Mixture, J. Y, Kim, C. H. Cho, P. Palffy-Muhoray, M. Mustafa, Thein Kyu

College of Polymer Science and Polymer Engineering

We have used light scattering to study the kinetics of polymerization-induced phase separation in a liquid-crystal-polymer mixture. The evolution of the structure factor is compared with scaling predictions for thermally quenched systems. We have also observed a cascading phenomenon where phase separated domains become unstable and undergo phase separation for a second time.

Evaluation Of Lime Stabilized Subgrade (Aa-19), Bobby W. Meade, David L. Allen

Kentucky Transportation Center Research Report

Construction of Section 19 of the Ashland-Alexandria Highway began in 1987. Because native soils have very low CBR values (1 to 3), it was decided to stabilize the soil subgrade with an application of 6% hydrated lime. The top 6 inches of the subgrade was to be stabilized. This process had not been previously used in Kentucky; and consequently, a research study was initiated to monitor this project. Objectives of the study were to monitor and document construction procedures, to determine the engineering characteristics of the treated subgrade through laboratory testing, and to report on the study findings. A substantial …

Survey Of The Impacts Of Environmental Regulations On State Highway Operations, Theodore Hopwood Ii, Christopher M. Oberst

Kentucky Transportation Center Research Report

In recent years, the transportation industry in Kentucky as represented by Kentuckians for Better Transportation (KBT) and the Kentucky Transportation Cabinet (KyTC), have expressed concern over the growing impact of environmental regulations upon transportation activities in the state. The imposition of environmental regulations has resulted in higher costs for new construction and maintenance on roads, project delays, scheduling and financing difficulties, and the creation of additional transportation agency bureaucracy to address environmental regulation mandates. In Kentucky, the impacts of those regulations have not been thoroughly assessed nor have the attendant costs been measured. Coinciding with that lack of information is …

Impacts Of The Extended-Weight Coal Haul Road System (Interim Report), Joseph D. Crabtree, Jerry G. Pigman, John A. Deacon, Kenneth R. Agent

Kentucky Transportation Center Research Report

The Extended-Weight Coal Haul Road System, created by Kentucky's Legislature in 1986, consists of all roads which carry over 50,000 tons of coal in a calendar year. Trucks hauling coal on this system are authorized to exceed normal weight limits through the payment of an annual decal fee. A research study was initiated in July of 1992 to analyze the impacts of the extended-weight system. This interim report, prepared after one year of a three-year study, describes the analyses performed thus far and presents preliminary findings, recommendations, and a discussion of future work.

Analyses in this report are based on: …

Declarative Representations Of Multiagent Systems, Munindar P. Singh, Michael N. Huhns, Larry M. Stevens

Faculty Publications

This paper explores the specification and semantics of multiagent problem-solving systems, focusing on the representations that agents have of each other. It provides a declarative representation for such systems. Several procedural solutions to a well-known test-bed problem are considered, and the requirements they impose on different agents are identified. A study of these requirements yields a representational scheme based on temporal logic for specifying the acting, perceiving, communicating, and reasoning abilities of computational agents. A formal semantics is provided for this scheme. The resulting representation is highly declarative, and useful for describing systems of agents solving problems reactively.

Proposal For A Dod Combined Battlefield Electromagnetic Environmental Effects (E3) Initiative, George H. Baker Iii

School of Integrated Sciences - Faculty Scholarship

The presentation emphasizes the growing importance of electromagnetic survivability and compatibility. Operation Desert Storm demonstrated the clear military advantage provided by sophisticated electronic weapon and communication systems. In addition, the offensive tactic of taking out the enemy's eyes and ears during the air war paid off, giving our military decisive air superiority. The lessons for the future are clear. High-tech electronics now so dominates the battlefield that the outcome of future conflicts could well be decided by electronics attrition rather than human casualties. Our Desert Storm experience thus accentuates the importance of guaranteeing that our electronic systems will not be …

Cyclo-Static Scheduling Of Large Grain Dataflow Algorithms On A Local Area Atamm Multicomputing Testbed, Sudeepto Roy

Electrical & Computer Engineering Theses & Dissertations

A strategy for cyclo-statically scheduling deterministic large grain dataflow (LGDF) algorithms for distributed execution on loosely coupled multicomputer architectures is presented in this research. The computational paradigm used is the ODU/NASA developed Algorithm To Architecture Mapping Model (ATAMM), which consists of marked graphs and Gantt chart representations that model the iterative execution of deterministic LGDF algorithms for different values of throughput and computation time. It is postulated that the behavior of these algorithms could be represented by the aggregate execution of an ensemble of cyclically shifted threads of a specific node sequence. Assuming the existence of one or more such …

Acoustic Correlates Of Vowel Perception As Determined From Synthesis Experiments With Multi-Tone Stimuli, Zhongjiang Zhang

Electrical & Computer Engineering Theses & Dissertations

An essential requirement of speech signal processing is to extract information (features or parameters) from the speech signal which encode the information carried by the signal. The objective of this thesis work was to examine and evaluate two feature sets as acoustic correlates for vowel perception. They are formants and DCTCs. Formants are the frequencies of spectral peaks of the speech signal. DCTCs are the Discrete Cosine Transform Coefficients of the magnitude spectrum and are thus features which encode the global spectral shape of speech signal.

There are different opinions regarding which feature set is a more accurate representation for …

Simultaneous Aerodynamic Analysis And Design Optimization, Satish Venkatasubra Mani

Mechanical & Aerospace Engineering Theses & Dissertations

An efficient approach for simultaneous aerodynamic analysis and design optimization is presented. Using this approach, the expensive procedure of performing complete steady— state flow analyses at every design-optimization step is avoided, thus addressing the challenge of incorporating computational fluid dynamics software into efficient gradient—based optimization techniques for aerodynamic design. An adjoint—variable method is introduced to nullify the effect of an increased number of design variables in this problem formulation. This approach is successfully tested on two quasi—one—dimensional nozzle—flow problems: a fully supersonic flow, and also a transonic flow with a normal shock. The algorithm is implemented using the direct Newton—iteration …

Numerical Simulation Of Two-Dimensional, Spatially Developing Mixing Layers, Robert V. Wilson

Mechanical & Aerospace Engineering Theses & Dissertations

Numerical simulation of a forced, two-dimensional, spatially-developing mixing layer using a control-volume formulation is performed. Three classes of forcing functions are used at the inlet boundary which are; (i) steady boundary conditions, (ii) combinations of the fundamental, first subharmonic, and second subharmonic modes from linear inviscid stability theory, and (iii) a broad spectrum of modes whose velocity power spectrum and transverse turbulence intensity relationship is taken from experiment. The results show that shear layer rollup occurs for time-dependent inlet boundary conditions and that the resulting vortex dynamics are determined from the subharmonic content of the inlet boundary conditions. It is …