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Full-Text Articles in Engineering

Advanced Navigation For Planetary Vehicles Applying An Approximate Mapping Technique, Timothy R. Mcjunkin May 1994

Advanced Navigation For Planetary Vehicles Applying An Approximate Mapping Technique, Timothy R. Mcjunkin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis provides a method for compressing the information provided by JPL Mars rover obstacle sensors by creating an approximate map of the terrain around the vehicle. This thesis demonstrates that this method provides adequate information for a human operator to negotiate complex obstacles fields.

By dividing the area around the vehicle into regions and classifying each region as to how dangerous (impassable), the sensor data can be accumulated with minimal overhead. The terrain in each region has a number between zero and one, with zero meaning completely passable and one meaning completely impassable. A continuum of possible values between …


The Design Of An Augmentative Communications Device, Darren Blaser, Scott Sorenson May 1994

The Design Of An Augmentative Communications Device, Darren Blaser, Scott Sorenson

Undergraduate Honors Capstone Projects

There is an extremely large number of people in the modem world who have difficulty communicating. Among these are approximately 25 million people with cerebral palsy. Cerebral palsy is a disability that is usually caused during, or shortly after birth. Cerebral palsy usually affects a person's motor skills and sense of balance, often rendering them incapable of speaking clearly enough to be understood well. Because this group of people cannot communicate as effectively as other individuals, many uninformed people suppose they do not have as great a need to speak, to say things like, "How are you?", ''I'm Hungry", "Thank …


Evaluation Of Flood Routing Techniques For Incremental Damage Assessment, Enan Fakhri Jayyousi May 1994

Evaluation Of Flood Routing Techniques For Incremental Damage Assessment, Enan Fakhri Jayyousi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Incremental damage assessment is a tool used to assess the justification for expensive modifications of inadequate dams. The input data to incremental damage assessment are the output from the breach analysis and flood routing. For this reason, flood routing should be conducted carefully. Distorted results from the flood routing technique or unstable modeling of the problem will distort the results of an incremental damage assessment, because an error in the estimated incremental stage will cause a certain error in the estimated incremental damages.

The objectives of this study were (1) to perform a comprehensive survey of the available dam break …


Load Transfer Mechanisms For Piles In Soft Soils, Andrew L. Palmer May 1994

Load Transfer Mechanisms For Piles In Soft Soils, Andrew L. Palmer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this thesis is to interpret pile load test data for several instrumented piles to determine the load transfer characteristics of driven piles in soft soils. Piles develop resistance to axial loads through two different mechanisms, side friction and end bearing. The rate that resistance develops is dependent upon soil type, pile type, and movement of the pile with respect to the soil. This thesis addresses load transfer for driven pipe piles in deep lacustrine deposits along the Wasatch Front area of Utah. The piles used in this study were installed for the support of highway structures in …


Design And Evaluation Of Stepped Spillways For High Dams, Jeffrey Scott Rau May 1994

Design And Evaluation Of Stepped Spillways For High Dams, Jeffrey Scott Rau

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this research was to investigate the hydraulic performance of stepped spillways. A thorough investigation was made of all printed material on stepped spillways, and a summary of this material is presented in the text. Data from experiments in the laboratory were used to develop a design procedure for stepped spillways and hydraulic jump stilling basins. The experimental study was conducted at Utah State University - Utah Water Research Laboratory in Logan, Utah. Four models were built and tested in the laboratory under various flowrates.

The crest of the model spillway was constructed in the shape of a …


Use Of Multispectral Aerial Videography For Jurisdictional Delineation Of Wetland Areas, James A. Shoemaker May 1994

Use Of Multispectral Aerial Videography For Jurisdictional Delineation Of Wetland Areas, James A. Shoemaker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Multispectral aerial videography was used to reproduce the jurisdictional delineation of wetland area of approximately 50 hectares in Davis County, Utah Imagery from the system consisted of three-band composite with wavelengths covering 550 nm (±10 nm), 650 nm (±10 nm), and 850 nm (±10 nm). The site was overflown at three different flight dates during the 1992 growing season (June 2, July 22, October 1). Imagery resolution varied from 0.56 m to 0.81 m. Mosaiced images were analyzed with a Supervised clustering/maximum likelihood classifier, ISODATA clustering/Euclidan classifier, statistical clustering/maximum likelihood classifier, and fuzzy c-means clustering. Overall accuracies for wetland/upland designations …


Modeling Of Natural Settling In A Trapezoidal Sedimentation Basin, Kent S. Wilkerson May 1994

Modeling Of Natural Settling In A Trapezoidal Sedimentation Basin, Kent S. Wilkerson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objectives of this thesis are to 1) review current theory relative to numerically modeling a trapezoidal settling basin, 2) develop a more appropriate model to better predict settling and deposition within a basin, and 3) confirm the accuracy of the model. The TSB (Trapezoidal Settling Basin) model was developed as part of this thesis. The Bureau of Reclamation's SETSIZE model performs similar analysis, but the TSB model makes significant improvements. The TSB model improves numerical modeling of a trapezoidal basin by allowing both sediment and sieve particle data, complex basin geometries with a multidimensional sediment deposition, and improved hydrograph …


A Three Dimensional Finite Element Thermo-Mechanical Analysis Of Intermittent Cutting, Mariam El Gallab May 1994

A Three Dimensional Finite Element Thermo-Mechanical Analysis Of Intermittent Cutting, Mariam El Gallab

Archived Theses and Dissertations

No abstract provided.


Experimental Investigation On The Dynamics Of Orthogonal Metal Cutting, Yasser Mohamed Ali May 1994

Experimental Investigation On The Dynamics Of Orthogonal Metal Cutting, Yasser Mohamed Ali

Archived Theses and Dissertations

No abstract provided.


Study Of The Compressive Strength Of Multidirectional Layered Glass Polyester Laminates, Hend Ahmed Amer May 1994

Study Of The Compressive Strength Of Multidirectional Layered Glass Polyester Laminates, Hend Ahmed Amer

Archived Theses and Dissertations

No abstract provided.


Multirate Time-Frequency Distributions, John R. O'Hair May 1994

Multirate Time-Frequency Distributions, John R. O'Hair

Theses and Dissertations

Multirate systems, which find application in the design and analysis of filter banks, are demonstrated to also be useful as a computational paradigm. It is shown that any problem which can be expressed a set of vector-vector, matrix-vector or matrix-matrix operations can be recast using multirate. This means all of numerical linear algebra can be recast using multirate as the underlying computational paradigm. As a non-trivial example, the multirate computational paradigm is applied to the problem of Generalized Discrete Time- Frequency Distributions GDTFD to create a new family of fast algorithms. The first of this new class of distributions is …


Logic Synthesis With High Testability For Cellular Arrays, Andisheh Sarabi Apr 1994

Logic Synthesis With High Testability For Cellular Arrays, Andisheh Sarabi

Dissertations and Theses

The new Field Programmable Gate Array (FPGA) technologies and their structures have opened up new approaches to logic design and synthesis. The main feature of an FPGA is an array of logic blocks surrounded by a programmable interconnection structure. Cellular FPGAs are a special class of FPGAs which are distinguished by their fine granularity and their emphasis on local cell interconnects. While these characteristics call for specialized synthesis tools, the availability of logic gates other than Boolean AND, OR and NOT in these architectures opens up new possibilities for synthesis. Among the possible realizations of Boolean functions, XOR logic is …


Patient Flow Through A Hospital Emergency Department, Mark Czuk Apr 1994

Patient Flow Through A Hospital Emergency Department, Mark Czuk

Honors Theses

Bronson Methodist Hospital, located in Kalamazoo, Michigan, is committed to the goal of providing comprehensive health care to the people of Southwestern Michigan. Bronson is actively involved in continually improving their services in order to better serve the community. This process of continuous improvement covers all hospital operations including the Emergency Department. Through studying the Emergency Department process, and how the department interacts with other departments in the hospital, improvements can be made which can lead to a better service provided to the community.


An Analysis Of The Linked-Pulse In Steady-State Free Precession In Mri, Fang Li Apr 1994

An Analysis Of The Linked-Pulse In Steady-State Free Precession In Mri, Fang Li

Dissertations and Theses

The steady-state free precession (SSFP) is one type of the fast scanning technique in MRI. So far most of its analysis are concentrated on the gradient echo SSFP (GR SSFP), very few paper discuss the spin echo SSFP (SE SSFP), and they are usually based on the simplified the hard pulse assumption. The advantage of the SE SSFP is that it can refocus the dephasing caused by the magnetic field inhomogeneity, which is the disadvantage of the GR SSFP. Also the hard pulse model can provide very limited information.

The purpose of this paper is to establish the soft pulse …


Developing A Benchmark For Evaluating The Performance Of Parallel Computers, D. Ladd Williamson Apr 1994

Developing A Benchmark For Evaluating The Performance Of Parallel Computers, D. Ladd Williamson

Undergraduate Honors Capstone Projects

This paper discusses the development of a portable suite of benchmarking programs for parallel computers. Comparative measurement of the performance of parallel computing systems has been limited because of the great diversity of architectures and of processor interconnection schemes. One solution is to translate benchmark codes into a consistent and portable parallel language. This paper reports on progress in developing such a portable suite of benchmarks. An extensive introduction to parallel computing is included as an appendix, to provide a thorough understanding of the factors complicating development of the performance suite. Key to the development was the use of p4, …


Performance Evaluation Tools For Interconnection Network Design, Anna Kolinska Apr 1994

Performance Evaluation Tools For Interconnection Network Design, Anna Kolinska

Dissertations and Theses

A methodology is proposed for designing performance optimized computer systems. The methodology uses software tools created for performance monitoring and evaluation of parallel programs, replacing actual hardware with a simulator modeling the hardware under development. We claim that a software environment can help hardware designers to make decisions on the architectural design level. A simulator executes real programs and provides access to performance monitors from user's code. The performance monitoring system collects data traces when running the simulator and the performance analysis module extracts performance data of interest, that are later displayed with visualization tools. Key features of our methodology …


Design Of A Vibration Excitation Device, Brian Wallace, Brandon Dawe Apr 1994

Design Of A Vibration Excitation Device, Brian Wallace, Brandon Dawe

Honors Theses

A vibration excitation source has been designed for use in beam and plate vibration laboratory demonstrations. This source is capable of providing single frequency excitations below 160 cycles per second (Hz). Since it will be used in a variety of experiments by students, ease of use and quick setup time have been major considerations of design. Performance of this source has been evaluated and will be presented along with one example application.


Motion Synthesis Of Mechanisms Using Constraint Manifolds In Image Space, Yeou-Kai Wu Apr 1994

Motion Synthesis Of Mechanisms Using Constraint Manifolds In Image Space, Yeou-Kai Wu

Dissertations

Kinematic mappings, quaternion algebra, and constraint manifolds in the algebraic image space are applied to the problems of the dimensional synthesis of mechanisms. Dimensions of a mechanism are determined such that a tracer frame fixed on the coupler will pass through or at least as close as possible to the desired positions and orientations in the physical space as the input link rotates about its fixed joint. First, using kinematic mappings, the desired positions and orientations of the tracer frame of the mechanism can be mapped onto points in a hyperspace in which the motion of the tracer frame can …


Behavior Of Biaxially Loaded Concrete-Encased Composite Columns, Pedro Ricardo Munoz Apr 1994

Behavior Of Biaxially Loaded Concrete-Encased Composite Columns, Pedro Ricardo Munoz

Dissertations

The theory of nonlinear behavior of biaxially loaded short and slender composite columns is used to study the load-deformation and moment-curvature of four pin-ended composite column specimens tested under axial compressive load and biaxial bending moments in a single curvature. The accuracy of the test results is verified by comparison with analytical results obtained by a method of analysis that includes the nonlinear material properties of concrete and steel and covers the ascending and descending branches of the linear segmented column specimen. A computational method is presented to model the analytical behavior of the biaxially loaded composite column. Its validity …


Satellite Data Communications Link Requirements For A Proposed Flight Simulation System, Gerald M. Kowalski Apr 1994

Satellite Data Communications Link Requirements For A Proposed Flight Simulation System, Gerald M. Kowalski

Master's Theses - Daytona Beach

The purpose of this study was to investigate the requirements necessary for data and voice communication via satellite, linking Embry-Riddle Aeronautical University (ERAU) and other flight training facilities. The proposed research was conducted following a descriptive method of collecting information, generating and analyzing data, and listing the results for the proposed link requirements. The current fiber-optic communications link at ERAU in Daytona Beach was presented to establish a general foundation of communications. Research was done into methods used by satellite common carriers for realistic data and calculations. A proposed data link to connect flight simulators at the ERAU Prescott campus …


The Effects Of Male-Based Anthropometric Cockpit Designs On Self-Reported Female Aircrew Accommodation, Edith Marie-Anntoinette Dylewska Apr 1994

The Effects Of Male-Based Anthropometric Cockpit Designs On Self-Reported Female Aircrew Accommodation, Edith Marie-Anntoinette Dylewska

Master's Theses - Daytona Beach

The purpose of this study was to examine the effects of male-based anthropometric cockpit designs on self-reported female aircrew accommodation. A descriptive survey research method was used to collect the required data. The instrument utilized was a self-developed questionnaire/opinionnaire. It contained both Likert-type and open-ended questions. The 153 subjects were selected from the population of active, civil, female pilots in the United States of America, who hold a Federal Aviation Administration (FAA) Airline Transport Pilot (ATP) Certificate. The responses provided to the Likert questions were analyzed using a goodness-of-fit statistical method. The data collected did not support the research hypothesis …


Internal Acoustic Excitation Of An Airfoil Surface For Drag Reduction, Wendy L. Holforty Apr 1994

Internal Acoustic Excitation Of An Airfoil Surface For Drag Reduction, Wendy L. Holforty

Masters Theses

This research investigated the effects of internal acoustic excitation on the boundary layer and surface of an airfoil. A NACA 16- 018 symmetric airfoil was tested in the Western Michigan University wind tunnel. The shedding vortex frequency of the airfoil was determined using hot-film anemometry. Using stroboscopic and holographic interferometry, the natural frequencies of the airfoil surface were determined. The airfoil surface was tuned such that the frequency of the shedding vortex is a resonant frequency and two internally mounted acoustic drivers were used to excite the surface of the airfoil at the shedding vortex frequency. The effects on pressure …


An Ergonomics Approach To Evaluate The Use Of Two Different Fixtures For Upholstering, Maria Luisa Roa Apr 1994

An Ergonomics Approach To Evaluate The Use Of Two Different Fixtures For Upholstering, Maria Luisa Roa

Masters Theses

A furniture company in West Michigan proposed an evaluation of a new fixture that will be used in a repetitive manual stapling operation.

Numerous studies reveal that activities involving repetitive wrist motions cause inflammation in the median nerve that runs through the structure of the carpal wrist, causing a cumulative disorder known as Carpal Tunnel Syndrome (CTS). This syndrome is one of the most prevalent in industrial settings and service companies.

This study investigated if the use of a new design of a fixture had an impact on operators' performances. Three-dimensional comparative analysis was used to observe operators' wrist angular …


Analysis Of Random Structure-Acoustic Interaction Problems Using Coupled Boundary Element And Finite Element Methods, Carl S. Pates Iii Apr 1994

Analysis Of Random Structure-Acoustic Interaction Problems Using Coupled Boundary Element And Finite Element Methods, Carl S. Pates Iii

Mechanical & Aerospace Engineering Theses & Dissertations

A coupled boundary element(BEM)-finite element(FEM) approach is presented to accurately model structure-acoustic interaction systems. The boundary element method is first applied to interior, two and three-dimensional acoustic domains with complex geometry configurations. Boundary element results are very accurate when compared with limited exact solutions.

Structure-interaction problems are then analyzed with the coupled FEM-BEM method, where the finite element method models the structure and the boundary element method models the interior acoustic domain. The coupled analysis is compared with exact and experimental results for a simplistic model. Composite panels are analyzed and compared with isotropic results. The coupled method is then …


A State Architecture Notation Specification Of The Electronic Industries Association Rs-232-C Generic Interchange Circuit, Nelson E. Hastings Apr 1994

A State Architecture Notation Specification Of The Electronic Industries Association Rs-232-C Generic Interchange Circuit, Nelson E. Hastings

Masters Theses

The Electronic Industries Association (BIA) RS-232-C recommendation is an interface specification which was introduced in August 1969 and presents a natural language specification of a 25 pin binary serial data interface between a Data Communication Equipment (DCE) and a Data Terminal Equipment (DTE). The exchange of data signals between a DCE and a DTE ultimately provides the means for DTEs to communicate on networks of DCEs interconnected by different transmission mediums possibly over great distances. The exchange of data signals between a DCE and a DTE occurs at an interface via interchange circuits.

In this thesis we will create a …


Three-Dimensional Aerodynamic Shape Optimization Using Discrete Sensitivity Analysis, Gregory Wayne Burgreen Apr 1994

Three-Dimensional Aerodynamic Shape Optimization Using Discrete Sensitivity Analysis, Gregory Wayne Burgreen

Mechanical & Aerospace Engineering Theses & Dissertations

An aerodynamic shape optimization procedure based on discrete sensitivity analysis is extended to treat three-dimensional geometries. The function of sensitivity analysis is to directly couple computational fluid dynamics (CFD) with numerical optimization techniques, which facilitates the construction of efficient direct-design methods. The development of a practical three-dimensional design procedures entails many challenges, such as: (1) the demand for significant efficiency improvements over current design methods; (2) a general and flexible three-dimensional surface representation; and (3) the efficient solution of very large systems of linear algebraic equations. It is demonstrated that each of these challenges is overcome by: (1) employing fully …


Transient Body Force Effects On The Dryout And Rewet Of A Heated Capillary Structure, Michael K. Reagan Apr 1994

Transient Body Force Effects On The Dryout And Rewet Of A Heated Capillary Structure, Michael K. Reagan

Theses and Dissertations

A transient, one-dimensional numerical code was developed to model the liquid flow in a non-uniformly heated, axial square groove. The groove was subjected to transient body forces up to approximately 0.51 m/s2 . Axial variation in meniscus levels, shear stress and heat transfer between the groove wall and the liquid, axial conduction through the liquid, evaporation and body forces were accounted for in the model. Dryout and rewet of the groove were allowed; the front location was determined using conservation of mass and linear extrapolation. A physical experiment was performed with a stainless steel plate into which eight square …


An Aerodynamic And Static-Stability Analysis Of The Hypersonic Applied Research Technology (Hart) Missile, Kenneth J. Moran Apr 1994

An Aerodynamic And Static-Stability Analysis Of The Hypersonic Applied Research Technology (Hart) Missile, Kenneth J. Moran

Theses and Dissertations

The flow about the complete Hypersonic Applied Research Technology (HART) missile is simulated for inviscid, laminar, and turbulent conditions and Mach numbers from 2 to 6. An explicit, second-order-accurate, flux-difference-splitting, algorithm is implemented and employed to solve the Navier-Stokes equations. The formulation models turbulence with the zero-equation, Baldwin-Lomax turbulence model, accounting for pressure-gradient and compressibility effects. The equations are solved using a finite-volume methodology. In the first part of the study, numerical experiments are performed using an infinitely thin-fin approximation. The aerodynamic and static-stability characteristics are investigated to determine if conventional supersonic missile configurations can be flown at Mach numbers …


Optimal Active And Passive Control Design For A Slewing Piezoelectric Laminate Beam, Travis V. Dubois Apr 1994

Optimal Active And Passive Control Design For A Slewing Piezoelectric Laminate Beam, Travis V. Dubois

Mechanical & Aerospace Engineering Theses & Dissertations

This thesis presents the development and experimental verification of a distributed parameter model for a slewing beam system with piezoelectric actuators and sensors. Also presented is the development of an optimal active control synergism which employs IMSC, (Independent Modal Space Control) and an optimally designed, viscoelastic damping treatment. The beam is pinned at the proximal end and patches of thin piezoelectric laminates are attached to its surface. Formulation is general enough to allow the patches to be located anywhere on the beam's surface. A viscoelastic material with a constraining layer covers the rest of the beam. The differential equation of …


A Direct Numerical Simulation Of Vortex Breakdown Induced Tail Buffet, Steven James Massey Apr 1994

A Direct Numerical Simulation Of Vortex Breakdown Induced Tail Buffet, Steven James Massey

Mechanical & Aerospace Engineering Theses & Dissertations

A simulation of tail buffet is presented for a delta wing-vertical tail configuration. Flow conditions are chosen such that the wing primary-vortex cores experience vortex breakdown and the resulting turbulent wake flow impinges on the vertical tail. The dimensions and material properties of the vertical tail are chosen such that the deflections are large enough to insure interaction with the flow, and the natural frequencies are high enough to facilitate a practical computational solution. This multidisciplinary problem is solved sequentially for the fiuid flow, the elastic deformations and the grid displacements. The fluid flow is simulated by time accurately solving …