Engineering Commons^™

A Market Profile Of Epc Foundries In North America, Jennifer D. Ballacchino

Graduate Research Papers

The purpose of this study is to discover what successes foundries are having with the EPC process and promote these successes. The EPC casting industry can use this information to encourage adoption of the process and thereby stimulate component conversion and application. Information gathered during this study will be consolidated into promotional materials about the EPC process. The materials will provide information to individuals in the industry, including foundries, suppliers and, most importantly, designers. Through sharing of information about the process, it can be better understood and acceptance may increase.

Acuta Enews July 1993, Vol. 22, No. 7

ACUTA Newsletters

In This Issue

Gain-share at Wake Forest

President's Message

North American Numbering Plan

Toll Fraud Checklist

Staff Report

Variable Structure End Point Control Of A Flexible Manipulator, Shailaja Chenumalla, Sahjendra N. Singh

Electrical & Computer Engineering Faculty Research

We treat the question of control and stabilization of the elastic multibody system developed in the Phillips Laboratory, Edwards Air Force Base, California. The controlled output is judiciously chosen such that the zero dynamics are stable or almost stable. A variable structure control (VSC) law is derived for the end point trajectory control. Although, the VSC law accomplishes precise end point tracking, elastic modes are excited during the maneuver of the arm. A Linear stabilizer is designed for the final capture of the terminal state.

Construction Report Fhwa Special Project 202, Break And Seat Of Jointed Reinforced Concrete Pavement, R. Clark Graves, David L. Allen

Kentucky Transportation Center Research Report

This study is part of the FHWA sponsored Special Project 202, "Break and Seat of Jointed Reinforced Concrete Pavement" (SP-202). In addition to Kentucky, West Virginia, Ohio, and Louisiana are also participating in the project. The projects were constructed under the experimental design defined in the FHWA Document "Special Project 202 Technical Resource Forum", June 6 and 7, 1989. Breaking patterns of 6, 18, and 30 inches, along with a control section which was not broken were used in each of the participating states.

The only major problem which occurred during construction occurred in the inside lane of the 6-inch …

Three Points Of Great Height On Elliptic Curves, Andrew Bremner, Duncan A. Buell

Faculty Publications

We give three elliptic curves whose generators have great height, demonstrating along the way a moderately efficient method for finding such points.

Cal Poly Model Canal, John B. Parrish, Iii, Charles M. Burt

BioResource and Agricultural Engineering

The Cal Poly Model Canal, located at the Water Delivery Facility. Irrigation Training and Research Center, California Polytechnic State University, San Luis Obispo, Calif., was built to accommodate the study and promotion of automated downstream control. Being a large, fully functional scale model of a canal, it was used to collect data for use by the Irrigation Canal System Hydraulic Modeling Task Committee of the ASCE Irrigation and Drainage Division. The data was used by Task Committee members to help evaluate numerical models for simulation of unsteady free-surface flow. The Model Canal and the collected data are discussed. This paper …

Irrigation-Canal - Simulation Model Usage, Charles M. Burt, Gregory Gartrell

BioResource and Agricultural Engineering

Unsteady canal-simulation model usage requires serious investments of time and personnel. The reasons for deciding to invest in a model, as well as reasons not to invest, are discussed. For most cases, it is better to invest in the improvement of an existing model than the writing of a new model. Many excellent models are available, although very few can be considered user-friendly for the average design engineer. Unsteady flow-simulation models are not recommended for real-time control, but are key tools for the study of various control scenarios. Canal models can simulate an actual canal, but the user must input …

Leukocyte Extravasation Into The Pancreatic Tissue In Transgenic Mice Expressing Interleukin 10 In The Islets Of Langerhans., Lise Wogensen, Xiaojian Huang, Nora Sarvetnick

Journal Articles: Regenerative Medicine

Transgenic expression of interleukin 10 (IL-10) in the islets of Langerhans leads to a pronounced pancreatic inflammation, without inflammation of the islets of Langerhans and without diabetes. A scattered infiltration of macrophages (M pi) precedes localized accumulations of CD4+ and CD8+ T lymphocytes, B lymphocytes, and M pi. This recruitment of inflammatory cells to the pancreas is somewhat surprising, since the biological activities of IL-10 in vitro indicate that IL-10 is a powerful immunosuppressive cytokine. Since endothelial cells play a major role in leukocyte extravasation, we examined if vascular changes and extralymphoid induction of peripheral and mucosal type vascular addressins …

Optimizing Irrigation Management For Pollution Control And Sustainable Crop Yield, G. R. Musharrafieh, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

We developed a simulation-optimization model which maximizes crop yield while maintaining target salt concentration in the root zone, and/ or preventing salt from leaching to the groundwater. The model performs nonlinear optimization and simulation. Implicit finite difference forms of the nonlinear, transient, unsaturated water flow equation, and the convection-diffusion equation are embedded as constraints. Other constraints include nonlinear functions describing the hydraulic properties of the medium. The objectives of the management model is to develop irrigation strategies which prevent salt leaching to the groundwater when salty irrigation water is used. Five different irrigation strategies are developed for Huntington Research Farm, …

Exergetic Cost Analysis Of A Mechanical Exergy Recycle, Jim Mcgovern

Conference Papers

A mechanical plant that involves an exergy recycle is presented for analysis. It consists of gearboxes and a fluid coupling. There is one input of shaft power to the plant and there are three separate outputs of shaft power. An exergetic cost analysis approach is outlined and applied to the plant.

Photoellipsometry Determination Of Surface Fermi Level In Gaas (100), Yi-Ming Xiong, Paul G. Snyder, John A. Woollam

Department of Electrical and Computer Engineering: Faculty Publications

Photoellipsometry, a new contactless optical method, is presented, Related to photoreflectance, this method utilizes spectroscopic ellipsometry with the addition of a laser pump beam directed at nearly normal incidence onto the sample surface, where photoexcited electron-hole pairs modify the built-in electric field as a result of the photovoltaic effect. The field-induced changes in the real and imaginary parts of the complex pseudodielectric function can be directly measured, and analyzed in terns of the pump beam power density or the probe beam photon energy to determine parameters, such as surface Fermi level, built-in field strength, depletion depth, broadening, critical point energies, …

Reduced Bandwidth For Remote Vehicle Operations, Timothy E. Noell, Fred W. Depiero

Electrical Engineering

Oak Ridge National Laboratory staff have developed a video compression system for low-bandwidth remote operations. The objective is to provide real-time video at data rates comparable to available tactical radio links, typically 16 to 64 thousand bits per second (kbps), while maintaining sufficient quality to achieve mission objectives. The system supports both continuous lossy transmission of black and white (gray scale) video for remote driving and progressive lossless transmission of black and white images for remote automatic target acquisition. The average data rate of the resulting bit stream is 64 kbps. This system has been demonstrated to provide video of …

A Technical Approach To Groundwater Contamination Problems, Jacqueline C. Burton, Catherine Leser, Candace M. Rose

United States Department of Energy: Publications

Argonne National Laboratory has been performing technical investigations at sites in Nebraska and Kansas that have identified groundwater contamination by carbon tetrachloride. This comprehensive program will ultimately provide the affected communities with safe drinking water. The first step in the program is to evaluate the available data and identify sites that will require an Alternate Water Supply Study (AWSS). The objective of the AWSS is to identify options for providing a safe drinking water supply to all users, in compliance with the Safe Drinking Water Act. The AWSS consists of an engineering and cost evaluation followed by implementation of the …

Brittle Compressive Failure Of Salt-Water Columnar Ice Under Biaxial Loading, T. R. Smith, E. M. Schulson

Dartmouth Scholarship

The brittle failure of saline columnar ice was investigated under biaxial compression at and −10° and −40°C over the range 0 ≤ R A < 1 where R A is the ratio of the intermediate to major principal compressive stress. The major principal stress and the intermediate (confining) stress were orthogonal to the columnar axes (type-A confinement); both stresses and the c-axes of the grains were co-planar. The results confirm earlier work by Hausier (1981) and Timco and Frederking (1983, 1986) on saline ice and follow similar behavior to fresh-water columnar ice found by Smith and Schulson (1993) and Frederking (1977). Failure stress and failure mode are sensitive to the confinement and two regimes of behavior are found: the failure stress first rapidly increases with R A in the range 0 ≤ R A < R T and then tends to decrease for R A > R t. The transition stress ratio, R t changes from ≈0.2 at −10°C to ≈0.1 at −40°C. The failure mode changes from axial splitting to shear faulting in the loading plane for 0 < R A < R t. Above R t failure changes to a combined mode of splitting across the columns and shear faulting out of the loading plane. The failure-stress envelope is of a truncated Coulomb-type. Damage studies show wing cracks and local fragmentation of grains involving the brine pockets. The results are explained in terms of Coulombic sliding and Hertzian crack mechanics.

Scattering Of A Light Beam From Waves At An Air-Sea Interface, Donald D. Duncan, W. H. Carter

Electrical and Computer Engineering Faculty Publications and Presentations

The authors report a new theory that describes the scattering of an upward propagating laser beam from the sea through the air-sea interface in the presence of sea waves. The sea is assumed to be a uniform dielectric and conventional scattering theory is employed by using a modification to the first Born approximation that permits treatment of surface refraction phenomena. Methods of statistical radiometry are also used in a new manner by assuming that the surface scattering function for the sea waves can be treated by a quasi-homogeneous source model to calculate the second-order correlation functions for the partially coherent …

The Naval Reserve Civil Engineer Corps Environmental Engineering Program, William A. Heine, Samuel A. Vigil

Civil and Environmental Engineering

The Navy is engaged in a national effort to bring its shore facilities into compliance with all applicable local, state, and federal environmental regulations. This work is being completed by civil service employees, consultants, and contractors under the supervision of Navy Civil Engineer Corps officers. To supplement these active duty and civilian resources, the Reserve Division of the Naval Facilities Engineering Command (RDNAVFAC) has identified Reserve officers with substantial environmental engineering skills who are being assigned to assist Navy shore activities all over the world in this essential task. The Naval Reserve Civil Engineer Corps (CEC) is composed of over …

Acuta Enews June 1993, Vol. 22, No. 6

ACUTA Newsletters

In This Issue

Telemedicine

Vancouver Review

Economy at Turning Point

Yale Meridian Upgrade

Executive Director's Message

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.

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.

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.

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 …

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. …

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 …

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 …

Feasible Offset And Optimal Offset For Single-Layer Channel Routing, Ronald I. Greenberg, Jau-Der Shih

Computer Science: Faculty Publications and Other Works

The paper provides an efficient method to find all feasible offsets for a given separation in a VLSI channel routing problem in one layer. The prior literature considers this task only for problems with no single-sided nets. When single-sided nets are included, the worst-case solution time increases from Theta(n) to Omega(n^2), where n is the number of nets. But, if the number of columns c is O(n), one can solve the problem in time O(n^{1.5}lg n ), which improves upon a `naive' O(cn) approach. As a corollary of this result, the same time bound suffices to find the optimal offset …

Preliminary Design Guide For Cold-Formed Steel C- And Z-Members, Committee On Specifications For The Design Of Cold-Formed Steel Structural Members

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

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 …