Engineering Commons^™

Man-Made Vibrations And Solutions, K. R. Massarsch

International Conference on Case Histories in Geotechnical Engineering

The generation and propagation of man-made vibrations in the ground is discussed. Emphasis is placed a simplified approach which is used to assess the most important factors, such as wave attenuation, refraction focusing and vibration amplification as a result of resonance. Practical guidelines are presented which can be used to predict vibrations and settlements in the ground. A semi-empirical relationship for the assessment of permissible vibration levels for buildings is proposed. Finally, a new ground vibration isolation method, the gas cushion screen is presented.

Practical Studies Of The Seismic Response Of A Rockfill Dam And A Tailings Impoundment, W. D. Liam Finn

International Conference on Case Histories in Geotechnical Engineering

Two case studies from engineering practice are presented to demonstrate how useful a sophisticated finite element analysis can be in providing a comprehensive understanding of how dams behave during earthquakes. The first example involves determining, from the recorded performance of a rockfill dam, the volume change characteristics of the rockfill which cannot be measured directly. The second example covers the full range of current capability for analysis. It involves dynamic effective stress analysis of a tailings dam to check the triggering of liquefaction and the analysis of post-liquefaction flow deformations.

Discussions And Replies: State Of The Art Papers, Mohamad Hussein, Fred H. Held Iii, C. Mirza, T. M. Davisson

International Conference on Case Histories in Geotechnical Engineering

No abstract provided.

A Probabilistic Model And A Software Tool For Avcs Longitudinal Collision/Safety Analysis, H.-S. Jacob Tsao, Randolph Hall

Faculty Publications

This paper develops a probabilistic model and a software tool for analyzing longitudinal collision/safety between two automated vehicles. The input parameters are the length of the gap between the two vehicles, the common speed prior to the failure, the reaction delay of the following vehicle and a bivariate pint distribution of the deceleration rates of the two vehicles. The output includes the probability of a collision and also the probability distribution of the relative speed at collision time.We will use this model to compare the safety consequences associated with the platooning and "free-agent" vehicle-following rules. We will also demonstrate that …

Numerical Algorithms For Squaring-Up Non-Square Systems Part Ii: General Case, Pradeep Misra

Electrical Engineering Faculty Publications

In this paper, we present numerical algorithms for squaring a non-square system by finding -additional columns in input matrix (for tall systems) and by finding additional rows in output matrix (for wide systems). Several case are considered depending up the requirements on the ra of the input-output interaction matrix.

Two-Tier Partially Enclosed Air-Cure Tobacco Barn, George A. Duncan

Agricultural Engineering Extension Publications

With the rising costs, scarcity of materials, and greater construction requirements for regular tobacco barns, the concept of a lower cost but functionally sound tobacco curing facility with partial or no sidewall closure has been developed into a blueprint plan shown in Figure 1. The plan can be built and used now with partial sidewalls and enclosed more completely later if desired.

Linear Characteristic Spatial Quadrature For Discrete Ordinates Neutral Particle Transport On Arbitrary Triangles, Dennis J. Miller

Theses and Dissertations

A new discrete ordinates spatial quadrature for arbitrary triangular cells is derived and compared to its rectangular cell linear characteristic counterpart. The triangular mesh is more flexible, allowing curved surfaces and off-axis angles to be approximated with many fewer spatial cells. The triangle method is consistently more accurate on example problems tested here. Arbitrary orientation and size of the triangles allow non-patterned meshes to be developed which appears to ameliorate numerical diffusion. The triangle linear characteristic quadrature converges at nearly the same rate as rectangular Linear characteristic on Lathrop's problem. Mesh sensitivity measurements show large variations in triangle vertex locations …

A Comparison Of Computational And Experimental Data For A Subscale High Speed Propulsive Nozzle At Low Mach Numbers, Yonghee Hyun

Theses and Dissertations

This computational study of a hypersonic sub-scale nozzle/cowl configuration compares numerical solutions with experimental data for nozzle performance at off design conditions (subsonic through supersonic Mach numbers. A combination of Van Leer and Roe flux-splitting algorithms was used to solve the flow field. The explicit formulation assumed laminar planar flow and the perfect gas equation of state. A validation for the numerical algorithm was accomplished by comparing with experimental data for a variety of cases. Grid refinement, geometry, and operating conditions all influenced the comparison of the experimental and computational data. Generally, as the Mach number and nozzle pressure ratio …

Experimental Investigation Of The Effects Of Blowing Ratio Parameter On Heat Transfer To A Film-Cooled Flat Plate, Marco R. Valencia

Theses and Dissertations

The effects of blowing ratio on film cooling effectiveness were investigated. Two round-nosed test plates were used. One made of aluminum and the second of corian (low thermal conductivity). Injection at 35 degrees in the downstream direction was studied. Helium was mixed with air to produce a density ratio (coolant to mainstream) of 1.6 and 2.0, while the blowing ratio varied from 0.3 to 2.2. Surface temperature was measured by thin film gages located up to a nondimensional downstream distance X/D of 30. Two injection regimes, weak and strong, were found. In the weak regime, film cooling reduced gage heat …

Development Of An Air-To-Air Refueling Automatic Flight Control System Using Quantitative Feedback Theory, Dennis W. Trosen

Theses and Dissertations

Quantitative Feedback Theory and the improved method Quantitative Feedback Theory are enhanced to include the rejection of disturbance at the system output. The enhanced Quantitative Feedback Theory and improved method Quantitative Feedback Theory processes are applied to the design of an automatic flight control system to regulate position of the C-135B fuel receiving aircraft relative to the tanker during air-to-air refueling. A simple feedback control system is developed that will achieve stable position regulation. State-space aircraft models &re generated. An inner loop autopilot is designed to reduce the plant cutoff frequency and provide the system inputs for the Quantitative Feedback …

Construction And Interim Performance Of A Pyrament Cement Concrete Bridge Deck, Michael D. Stone, David Q. Hunsucker

Kentucky Transportation Center Research Report

Pyrament Blended Cement (PBC) is a high performance cement developed by Lone Star Industries and is a blend of 65% portland cement, 30% fly ash, and 5% trademark additive. Concrete made with PBC has been characterized by its rapid set, high early strength, and low permeability. This report summarizes the construction and interim performance of a full-depth concrete bridge deck slab constructed using Pyrament Cement concrete.

Utilization Of Fossil-Fuel Related By-Product Materials For Highway Construction In Kentucky, David Q. Hunsucker

Kentucky Transportation Center Research Report

In an effort to increase the utilization of fossil-fuel by product materials in highway construction project, the Kentucky Transportation Cabinet authorized the experimental use of several waste materials. These materials included bottom ashes, fly ash, scrubber sludge, multicone kiln dust, and residues tram atmospheric fluidized bed combustion processes. Bottom ash aggregate was used as a partial replacement for the limestone aggregate in a bituminous surface mix. Non-specification fly ash was used in lieu of Class F fly ash in a stabilized aggregate base. Bottom ash stabilized with residue from an atmospheric fluidized bed combustion process was used as a highway …

Study Of Single-Electron Capture From He, Ne And Ar By Low-Energy Ne^Q+ Recoil Ions Using Translational Energy Spectroscopy, Renad Qubaj-Said

Masters Theses

No abstract provided.

Tolerance Specification Of Robot Kinematic Parameters Using An Experimental Design Technique, Y.H. Andrew Liou, Paul P. Lin, Richard R. Lindeke, Hsiang-Dih Chiang

Mechanical Engineering Faculty Publications

This paper presents the tolerance specification of robot kinematic parameters using the Taguchi method. The concept of employing inner and outer orthogonal arrays to identify the significant parameters and select the optimal tolerance range for each parameter is proposed. The performance measure based on signal-to-noise ratios (S/N) using the Taguchi method is validated by Monte Carlo simulations. Finally, a step-by-step tolerance specification methodology is developed and illustrated with a planar two-link manipulator and a five-degree-of-freedom Rhino robot.

Optimization Of The Seating Position In A Human-Powered Vehicle, Y. Lei, Mohamed Trabia, D. Too

Mechanical Engineering Faculty Research

Until recently, most of the human-powered vehicles (HPV) were designed focusing solely on its aerodynamics characteristic. In many of these HPV designs, the rider seating position was arbitrarily chosen without consideration of its effect on the rider's comfort and cycling effectiveness. Also, there is no guarantee that the seating position is related to maximum power output. Too (1991) used an experimental approach to determine that the rider will produce the maximum anaerobic power when the seat tube angle of a bicycle is at 75° whereas Hull and Gonzalez (1990) used an engineering approach to optimize the cycling biomechanics. However several …

Applicant's Guide To Traffic Impact Studies, Soumya Sekhar Dey, Jon D. Fricker

JTRP Technical Reports

No abstract provided.

Performance Of Experimental Highway Base And Subbase Layers Containing Coal-Fired Power Plant By-Product Materials: Ky Route 3074, Bleich Road, David Q. Hunsucker, R. Clark Graves

Kentucky Transportation Center Research Report

Three 750-foot test sections of a 22-foot wide roadway were constructed on newly constructed subgrade in May and June, 1988. The three experimental sections contained experimental base and subbase layers comprised of mixtures utilizing by-product materials from a coal-fired power plant One test section included a base layer containing residue from an atmospheric fluidized bed combustion (AFBC) process, size No. 57 aggregate, and Class F fly ash. The second test section included a base layer constructed ponded fly ash, hydrated lime, and dense-graded aggregate. The third test section included a subbase layer constructed of pond ash stabilized with AFBC residue. …

Thermal Behavior Of A Stratified Cylindrical Energy Storage Tank, Sheherazad Youssef Ezz Eldeen Ahmed Korayem

Archived Theses and Dissertations

No abstract provided.

Evaluation Of Dynamic Stresses And Fatigue Life Prediction For Randomly Loaded Structure, Walied Ahmed Moussa

Archived Theses and Dissertations

No abstract provided.

Bs News

Building Services Engineering

No abstract provided.

Photopolarimeter Based On Planar Grating Diffraction, R. M.A. Azzam, K. A. Giardina

Electrical Engineering Faculty Publications

A division-of-amplitude photopolarimeter (DOAP) is described that employs a diffraction grating in the conventional spectrometer orientation with the grating grooves normal to the plane of incidence. Four coplanar diffracted orders are used for polarimetric analysis to determine all four Stokes parameters of incident light simultaneously and virtually instantaneously (with the speed being determined solely by the photodetectors and their associated electronics); a fifth order is used for alignment by autocollimation or by use of a position-sensing quadrant detector. To sensitize the instrument for the +45° and -45° azimuths of incident linearly polarized light and for the handedness of incident circular …

Spectroscopic Ellipsometry Studies Of Hf Treated Si (100) Surfaces, Huade Yao, John A. Woollam, Samual A. Alterovitz

Department of Electrical and Computer Engineering: Faculty Publications

Both ex situ and in situ spectroscopic ellipsometry (SE) measurements have been employed to investigate the effects of HF cleaning on Si surfaces. The hydrogeniterminated (H-terminated) Si surface was modeled as an equivalent dielectric layer, and monitored in real time by SE measurements. The SE analyses indicate that after a 20-s 9:l HF dip without rinse, the Si ( 100) surface was passivated by the hydrogen termination and remained chemically stable. Roughness of the HF-etched bare Si (100) surface was observed, in an ultrahigh vacuum (UHV) chamber, and analyzed by the in situ SE. Evidence for desorption of the H-terminated …

Drainage Basins And Flash Flood Hazards In Al-Ain Area, United Arab Emirates, Moza Hamad Al-Shamsi

Civil and Environmental Theses

Flash flood strike different parts of Al-Ain area virtually every year causing Serious property loses this study investigates the main factors control ling this Flooding, namely. (a) Climate, (b) geomorphology, and (c) hydrogeology Climatically, mo t of rainstorms do occur during the month of February. Geomorphologic ally, the landforms and drainage systems are the main factors. Hydrogeological, twenty basins were carefully identified and their morphometric Parameters were measured the relations between these morphometric parameters and flash floods were accordingly assessed. The results show that most severe damage did occur in buildings and farms in Al Ain Area the most influential …

Phased Array Antenna Analysis Using Hybrid Finite Element Methods, Daniel T. Mcgrath

Theses and Dissertations

This research in computational electromagnetics developed a new method for predicting the near-field mutual coupling effects in phased array antennas, using the finite element method (FEM) in combination with integral equations. Accurate feed modeling is accomplished by enforcing continuity between the FEM solution and an arbitrary number of wave guide models across a ground plane aperture. A periodic integral equation is imposed above the antenna's physical structure in order to enforce the radiation condition and to confine the analysis to an array unit cell. The electric field is expanded in terms of vector finite elements, and Galerkin's method is used …

A Decision Criteria To Select An Associative-Memory Organization That Minimizes The Execution Time Of A Mix Of Associative-Search Operations, David W. Banton

Theses and Dissertations

The dissertation develops a decision criteria to select an associative-memory organization that minimizes the execution time of a mix of associative-search operations and a decision criteria to estimate the layout dimensions of each organization for a specified memory size. The dissertation reclassifies Feng's associative-search operations into three hardware-influenced categories: bit-position independent (BPI), record-content independent (RCI); bit-position dependent (BPD), RCI; and BPD, record-content dependent (RCD). It develops a relationship between the categories and three associative-memory organizations: the CAM, the bit-serial word-parallel associative memory (BSWPAM) , and the extreme-search associative memory (ESAM). A version of the CAM, three versions of the BSWPAM, …

Experimental And Analytical Analysis Of The Response Of A Smart Beam To Rate Feedback, Terance J. Hoffman

Theses and Dissertations

A smart beam with embedded sensors and actuators was analyzed and tested. The smart beam studied was constructed from graphite and epoxy with piezoceramic actuators and NiTiNOL sensors embedded. It was mounted vertically and subjected to transverse dynamic loading at the free end. Analytic expressions for the open loop and closed loop response (using strain rate feedback control) of the beam (including internal damping) to external forcing were derived in detail. Experimental testing of the beam verified the accuracy of the predicted open loop response.

Radome Depolarization Effects On Monopulse Receiver Tracking Performance, Michael A. Temple

Theses and Dissertations

Boresight Error (BSE), defined as the angular deviation between the true position and the apparent position of a target as indicated by a radar, is an important figure of merit for a tracking radar. A significant contributor to system BSE is the protective radome. This research effort employed a GO technique to investigate the effects of a radome on BSE, expanding previous ray- trace receive techniques to include: (1) a uniquely defined/developed mathematical description for each surface within arbitrary multi-layer tapered radomes, (2) an 'ideal' taper function concept for obtaining optimum BSE prediction performance, (3) a generalized technique for calculating …

Building A Gateway For The Cd-Rom Network: A Step Toward The Virtual Library With The Virtual Microsystems V-Server, Margaret Sylvia

Faculty Publications

Describes one college library's experience with a gateway for dial-in access to its CD-ROM network to increase access to automated index searching for students off-campus. Hardware and software choices are discussed in terms of access, reliability, affordability, and ease of use. Installation problems are discussed, and an appendix lists product information.

Nonlinear Dynamic Finite Element Simulation Of Hydroelastic Mounts For Light Weight Vehicles, Talla Jayapal Reddy

Masters Theses

Modern light weight vehicles generate large noise levels, that may need bulky classical rubber mounts to suppress. Hydroelastic mounts can significantly reduce the vibration level of current production automobiles without weight penalty. However, the highly nonlinear behavior of hydroelastic mounts has not been established yet and its use is, therefore, limited to trial and error design methods.

This study discusses the implementation of nonlinear finite element simulation of hydroelastic mounts using the ANSYS finite element code. Fluid elements are limited to linear analysis and therefore are incompatible with the nonlinear hyperelastic elements. A method is proposed to simulate the fluid …

A Generalized Data Conversion System, Kevan Morgan

Undergraduate Honors Capstone Projects

To assist in the processing of data files collected by the Space Dynamics Laboratory at Utah State University, the software project GENDACS has been completed. GENDACS, acronym for A Generalized Data Conversion System, will contribute to its research program.

Data are collected from various sensory instruments by the Computer Data Acquisition System. The instrument readings are brought in, tagged with the time they were taken, and stored on an optical disk in a compact, binary (non-ASCII) format. GENDACS is designed so that the program can read in such files, sort out the data, and convert them into a new ASCII …