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Biomechanical Comparison Of Interosseous And Subperiosteal Flexor Tendon Reattachment, Alisa Beth Olin Jan 1994

Biomechanical Comparison Of Interosseous And Subperiosteal Flexor Tendon Reattachment, Alisa Beth Olin

Theses

This study was undertaken to biomechanically compare the interosseous and subperiosteal distal flexor tendon reattachment techniques. Twenty New Zealand white rabbits underwent division of the right second and third hind limb profundus flexor tendon distal to the insertion of the superficial flexor. All tendons were repaired using the Kleinnert-Bunnell configuration with a 5-0 nylon tied over a cotton pad on the dorsum of the digit. In half of the animals, the second profundus was reattached into a hole in the middle phalanx and the third profundus was reattached after periosteal stripping of the middle phalanx. The other animals underwent subperiosteal …


Development And Evaluation Of A Nfweav Simulation Model For Weaving Areas Under Non-Freeway Condition, Wen-Min Pan Jan 1994

Development And Evaluation Of A Nfweav Simulation Model For Weaving Areas Under Non-Freeway Condition, Wen-Min Pan

Theses

The development of a microscopic digital computer simulation model representing vehicle interaction at a weaving area under non-freeway condition is presented. Weaving areas are classified into two categories: 1. Weaving caused by merging and diverging of a ramp with an arterial, 2. On/off ramps connecting an arterial with a highway. The principal characteristics of the simulation model are the following: 1) a car following and lane changing model were used to represent vehicle movements; 2) an anti-collision check algorithm was developed for all vehicle movements; 3) driver merging urgency and follower courtesy model were developed for weaving vehicles. The simulation …


Coping With The Risk Of Cancer In Children Living Near Power Lines, Eileen N. Abt Jan 1994

Coping With The Risk Of Cancer In Children Living Near Power Lines, Eileen N. Abt

RISK: Health, Safety & Environment (1990-2002)

Ms. Abt briefly summarizes evidence linking power lines with a possible increase in risk of childhood cancer. She also recounts how, although many experts remain skeptical of causality, public fears, whether or not warranted, have themselves created serious problems. Finally, she proposes ways to address those problems.


An Exploratory Study Of Hypermedia Support For Problem Decomposition, Robert P. Minch, Gary I. Green Jan 1994

An Exploratory Study Of Hypermedia Support For Problem Decomposition, Robert P. Minch, Gary I. Green

IT and Supply Chain Management Faculty Publications and Presentations

Empirical hypermedia research has concentrated on usability rather than utility, and the research on utility has focused on information access as opposed to problem solving and decision making in organizations. This study, based on problem reduction theory, uses a hypermedia prototype system to support decision processes for solving a financial analysis problem. An exploratory laboratory experiment was conducted to study the feasibility of the prototype for hypermedia support of decision making. The process tracing techniques used suggest that a cognitive map of a decision maker's thought process may be constructed. Results offer a great deal of promise in the use …


Biological Assessment For Maintenance Of Bank Stabilization Structures Missouri National Recreation River Gavins Point Dam To Ponca State Park, Nebraska Jan 1994

Biological Assessment For Maintenance Of Bank Stabilization Structures Missouri National Recreation River Gavins Point Dam To Ponca State Park, Nebraska

United States Army Corps of Engineers, Omaha District

The location of the proposed maintenance construction project discussed in this document is located between Gavins Point Dam, South Dakota and Ponca, Nebraska, at specific locations as listed in the accompanying plans and specifications.

The proposed construction consists only of maintaining those structures that can reasonably be repaired to alleviate erosion problems for the purpose of maintaining the structural integrity of the existing structures. Any structure that is beyond repair would not be reconstructed, since it would no longer qualify as maintenance. There are nine existing projects within the Missouri National Recreation River (MNRR) segment of the Missouri River. Each …


Oscillating Flow In Channels With Sudden Change In Cross Section, Mounir B. Ibrahim, Waqar Hashim Jan 1994

Oscillating Flow In Channels With Sudden Change In Cross Section, Mounir B. Ibrahim, Waqar Hashim

Mechanical Engineering Faculty Publications

In this paper, we have computationally examined oscillating flow (zero mean between) two parallel plates with a sudden change in cross section. The flow was assumed to be laminar incompressible with the inflow velocity uniform over the channel cross section but varying sinusoidally with time. The cases studied cover wide ranges of Remax (from 187.5 to 2000), Va (from 1 to 10.66), the expansion ratio (1:2 and 1:4) and Ar (2 and 4). Also, three different geometric cases were discussed: (a) asymmetric expansion/contraction; (b) symmetric expansion/contraction; and (c) symmetric blunt body. For these oscillating flow conditions, the fluid …


Impulse, Cindy Maisch, Samantha Penney, Lois Hatton, Dana Bieber, Todd Hammond Jan 1994

Impulse, Cindy Maisch, Samantha Penney, Lois Hatton, Dana Bieber, Todd Hammond

Impulse (Jerome J. Lohr College of Engineering Publication)

Features:
[Page 2-3] Solberg family hopes to continue legacy
[Page 3] Solberg Loan Fund helps needy students
[Page 4-5] Alumnus achieves unique success
[Page 5] Inventors Congress enters second year
[Page 6] Basilio Gonzalez helps Somalia rebuild
[Page 7] Empi CEO named 1993 Entrepreneur of the Year
[Page 7] Empi makes Forbes list
[Page 8] Jensen wins ASME award
[Page 9] Utility industry: a past, present and future of changes
[Page 10-11] Daktronics celebrates 25th anniversary
[Page 10-11] Daktronics wins Business of the Year, seven other awards
[Page 11] Wilkens to retire as CEO of Northwestern Public Service
[Page 11-14] …


Kentucky Traffic Accident Facts 1994 Report, Kentucky Transportation Center, Kentucky State Police Jan 1994

Kentucky Traffic Accident Facts 1994 Report, Kentucky Transportation Center, Kentucky State Police

Kentucky Transportation Center Research Report

KENTUCKY'S TRAFFIC ACCIDENT FACTS report for 1994 is based on accident reports submitted to the Accident Unit housed in the Kentucky State Police Information Services Branch, Records Section. As required by Kentucky Revised statutes 189.635, "every law enforcement agency whose officers investigate a vehicle accident of which a report must be made ... shall file a report of the accident...within ten days after investigation of the accident upon forms supplied by the bureau." The stated purpose of this requirement is to utilize date on traffic accidents" for such purposes as will improve the traffic safety program in the Commonwealth." Data …


Proposal For Development Of A Resource And Commodity Highway System, John A. Deacon, David L. Allen, Joseph D. Crabtree, Kenneth R. Agent, Jerry G. Pigman, R. Clark Graves Jan 1994

Proposal For Development Of A Resource And Commodity Highway System, John A. Deacon, David L. Allen, Joseph D. Crabtree, Kenneth R. Agent, Jerry G. Pigman, R. Clark Graves

Kentucky Transportation Center Research Report

In 1986, the Kentucky General Assembly established the Extended Weight Coal and Coal By-Products Haul Road System. This system includes approximately 3,200 miles of the most significant coal-haul roads in the state and permits coal trucks to carry much larger payloads than trucks with other commodities. In many ways, the extended-weight system has been very successful. Coal-transportation productivity has been substantially increased, and Kentucky coal continues to remain competitive in the marketplace. At the same time, infrastructure costs have risen substantially--to considerably greater levels than the increase in revenue produced by the requisite coal decal fees--and the extended-weight system has …


Multimedia Application Synthesis Study, Bob G. Mccullouch Jan 1994

Multimedia Application Synthesis Study, Bob G. Mccullouch

JTRP Technical Reports

Multimedia with its ability to involve various human faculties through the use of various media forms, provides a robust environment in which to learn in. Retention improves significantly when media exercises these various human faculties. Studies indicate that students complete training in one-third the time of the traditional instruction method while reaching up to 50 percent higher competency levels. Utilizing this technology can provide improved training tools and learning environments for the Department. Because of the many potential applications, technical and nontechnical, that may exist within the Department for utilizing this technology; a study was performed to answer questions about …


The Integration Of Simulation And Reality For Education Enhancement And Training, Clarence Rasquinha, Stephen A. Raper Jan 1994

The Integration Of Simulation And Reality For Education Enhancement And Training, Clarence Rasquinha, Stephen A. Raper

Engineering Management and Systems Engineering Faculty Research & Creative Works

Quite often, when engineers are exposed to a manufacturing environment on the job for the first time, they undergo a baptism by fire. The environment forces them to deal with situations that integrate many different bodies of knowledge. Reliance on concepts acquired in the academic environment is crucial to their success. Unfortunately, lacking in most academic environments, is any experience through which some or all of these concepts are integrated. In a continuing effort to enhance educational practices in Manufucturing/Systems Engineering programs and perhaps improve the preparedness of a young engineer, the CITE (Computer Integrated Technological Enterprise) tool offers educators …


The Evolution Of Abdominal Compression In Cardiopulmonary Resuscitation, Charles F. Babbs Jan 1994

The Evolution Of Abdominal Compression In Cardiopulmonary Resuscitation, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Publications

Objective: To review the history of external abdominal compression as an adjunct to cardiopulmonary resuscitation (CPR), tracking the development of five major themes over the course of the 20th century: 1) augmentation of peripheral resistance by physical means, 2) risk of hepatic injury with abdominal compression, 3) counterpulsation vs. sustained compression, 4) the abdominal pump mechanism, and 5) contact compression techniques. Methods: Literature retrieved from successive MEDLINE English-language searches was reviewed with a special emphasis on work and concepts highlighted by participants at the First Purdue Conference on Interposed Abdominal Compression-CPR, September 1992. Results: External abdominal compression of one form …


Interposed Abdominal Compression As An Adjunct To Cardiopulmonary Resuscitation, Charles F. Babbs, Jeffrey B. Sack, Karl B. Kern Jan 1994

Interposed Abdominal Compression As An Adjunct To Cardiopulmonary Resuscitation, Charles F. Babbs, Jeffrey B. Sack, Karl B. Kern

Weldon School of Biomedical Engineering Faculty Publications

The addition of interposed abdominal compression (IAC) to otherwise standard CPR provides external pressure over the abdomen in counterpoint to the rhythm of chest compression. Interposed abdominal compression is a simple manual technique that can supplement the use of adrenergic drugs to increase both coronary perfusion pressure and total blood flow during CPR. Mechanistically, manual abdominal compressions induce both central aortic and central venous pressure pulses. However, owing to differences in venous versus arterial capacitance, the former are usually greater than the latter, so that systemic perfusion pressure is enhanced. Moreover, practical experience and theoretical analysis have suggested subtle refinements …


Ascertaining Important Features For Industrial Simulation Environments, Gerald Mackulak, Jeffery Cichran, Paul Savory Jan 1994

Ascertaining Important Features For Industrial Simulation Environments, Gerald Mackulak, Jeffery Cichran, Paul Savory

Department of Industrial and Management Systems Engineering: Faculty Publications

Recent years have witnessed the development and commercial release of multiple simulation tools, environments, and intelligent simulators. Each release seems to contain additional advanced features designed to simplify simulation use and increase the productivity of model builders. But to date, no one has addressed feature definition from the viewpoint of a simulation practitioner. This paper discusses our efforts to identify and prioritize simulation features deemed most desirable from the practitioner viewpoint. A series of three questionnaires were developed and administered to a group of qualified simulation practitioners. With results that are of interest to simulation users, researchers, and simulation software …


Final Environmental Assessment For Endangered Species Habitat Improvement/Creation In The Missouri River Between The Niobrara River And Ponca, Nebraska Jan 1994

Final Environmental Assessment For Endangered Species Habitat Improvement/Creation In The Missouri River Between The Niobrara River And Ponca, Nebraska

United States Army Corps of Engineers, Omaha District

An environmental assessment has been prepared for new habitat development in upper Lewis and Clark Lake and the Missouri River below Gavins Point Dam. The actions described are in response to the November 1990, U.S. Fish and Wildlife Service Biological Opinion on the operation of the Missouri River Main Stem System, and will provide safer nesting habitat for the interior least tern (endangered species) and the piping plover (threatened species).

Vegetation on the river islands will be removed and maintained in the "sparsely vegetated" state needed for nesting habitat for the terns and plovers. After vegetation removal, the islands will …


The Status Of Nebraska Fishes In The Missouri River. 6. Sauger (Percidae: Stizostedion Canadense), Larry W. Hease Jan 1994

The Status Of Nebraska Fishes In The Missouri River. 6. Sauger (Percidae: Stizostedion Canadense), Larry W. Hease

United States Army Corps of Engineers, Omaha District

Saugers were once common representatives of the Missouri River fish assemblage. Prior to channelization and impoundment, they comprised from 10 to 65% of the main channel big-river fish group. They utilized the slower side channels and backwaters seasonally for feeding, resting, and maturing, but the main channel was important for breeding habitat, Since the onset of channelization and impoundment, saugers have been reduced by as much as 98% in some areas, and the trend toward extirpation continues unabated today. Recovery of native sauger stocks will require a complete cessation of harvest, recovery of the natural hydrograph, recovery of sediment transport, …


Water Vapor Permeability And Mechanical Properties Of Grain Protein-Based Films As Effected By Mixtures Of Polyethylene Glycol Amd Glycerin Plasticizers, H. J. Park, J. M. Bunn, Curtis L. Weller, P. J. Vergano, R. F. Testin Jan 1994

Water Vapor Permeability And Mechanical Properties Of Grain Protein-Based Films As Effected By Mixtures Of Polyethylene Glycol Amd Glycerin Plasticizers, H. J. Park, J. M. Bunn, Curtis L. Weller, P. J. Vergano, R. F. Testin

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Grain protein-based films containing mixtures of glycerin and polyethylene glycol (PEG) as plasticizers were prepared and evaluated for water vapor permeability (WVP), tensile strength (TS), and elongation (E). Changes in mechanical properties during storage were also studied. The PEG produced opposite trends in E of wheat gluten and corn-zein films. The TS of wheat gluten films increased and E of the films decreased as the ratio of glycerin/PEG decreased. Corn-zein films containing only glycerin were very brittle (E of 4%), and E of the films improved to 94% when the ratio of mL PEG/g protein was 0.39. The WVP of …


Identification Of Tire Leachate Toxicants And A Risk Assessment Of Water Quality Effects Using Tire Reefs In Canals, S. M. Nelson, G. Mueller, D. C. Hemphill, U.S. Bureau Of Reclamation Jan 1994

Identification Of Tire Leachate Toxicants And A Risk Assessment Of Water Quality Effects Using Tire Reefs In Canals, S. M. Nelson, G. Mueller, D. C. Hemphill, U.S. Bureau Of Reclamation

Publications (WR)

Cover is an important component of aquatic habitat and fisheries management. Fisheries biologists often try to improve habitats through the addition of natural and artificial material to improve cover diversity and complexity. Habitat-improvement programs range from submerging used Christmas trees to more complex programs using sophisticated artificial habitat modules. Used automobile tires have been employed in the large scale construction of reefs and fish attractors in marine environments and to a lesser extent in freshwater and have been recognized as a durable, inexpensive and long-lasting material which benefits fishery communities.

Recent studies by the U.S. Bureau of Reclamation have quantified …


Hycrest Crested Wheatgrass Accelerates The Degradation Of Pentachlorophenol In Soil, A. Ferro, Ronald C. Sims, B. Bugbee Jan 1994

Hycrest Crested Wheatgrass Accelerates The Degradation Of Pentachlorophenol In Soil, A. Ferro, Ronald C. Sims, B. Bugbee

Biological Engineering Faculty Publications

We investigated the effects of vegetation on the fate of pentachlorophenol (PCP) in soil using a novel high-flow sealed test system. Pentachlorophenol has been widely used as a wood preservative, and this highly toxic biocide contaminates soil and ground water at many sites. Although plants are known to accelerate the rates of degradation of certain soil contaminants, this approach has not been thoroughly investigated for PCP. The fate of [14C]PCP, added to soil at a concentration of 100 mg/kg, was compared in three unplanted and three planted systems. The plant used was Hycrest, a perennial, drought-tolerant cultivar of crested wheatgrass …


The Effect Of Active And Passive Control On Air Traffic Controller Dynamic Memory, Esa M. Rantanen Dec 1993

The Effect Of Active And Passive Control On Air Traffic Controller Dynamic Memory, Esa M. Rantanen

Master's Theses - Daytona Beach

The purpose of this study was to investigate the effect of automated and passive control on air traffic controller dynamic memory. The study consisted of two experiments, each involving a realistic ATC scenario for radar approach control with a mix of arriving and departing traffic. In Experiment I, the subjects performed manual control of the traffic while, in Experiment II, the scenario was highly automated and the subjects were tasked with only monitoring the situation. The dynamic memory performance was measured by interrupting the scenario and having the subjects recall the traffic situation at the moment of simulation interruption. The …


Wildlife Exposure Factors Handbook, Appendix: Literature Review Database, Volume Ii Of Ii, United States Environmental Protection Agency Dec 1993

Wildlife Exposure Factors Handbook, Appendix: Literature Review Database, Volume Ii Of Ii, United States Environmental Protection Agency

United States Environmental Protection Agency: Publications

This Appendix is intended to accompany the Wildlife Exposure Factors Handbook (hereafter referred to as the Handbook) and should be used only by individuals familiar with the Handbook. The species-specific values for the exposure factors presented in Chapter 2 of the Handbook of are a subset of the data included in the tables of this Appendix. Most values identified in the literature reviewed for the Handbook are included in this Appendix. For some exposure factors for some species, large quantities of data are available. For these factors and species, we tried to select data that represented a range of values …


Bulletin 4265 - Termites, Peter Davis Dec 1993

Bulletin 4265 - Termites, Peter Davis

Bulletins 4000 -

Termites are small, soft-bodied, social insects that feed on wood, grass, dead leaves, bark, humus, fungi or the dung of herbivore. They are commonly known as white ants, but are not related to true ants.

There are over 2300 species of termite of which about350 occur in Australia, and of these about 12 damage sound timber.


Script-Based Qos Specifications For Multimedia Presentations, Richard Staehli, Jonathan Walpole Dec 1993

Script-Based Qos Specifications For Multimedia Presentations, Richard Staehli, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Multimedia presentations can convey information not only by the sequence of events but by their timing. The correctness of such presentations thus depends on the timing of events as well as their sequence and content. This paper introduces a formal specification language for playback of real-time presentations. The main contribution of this language is a quality of service (QOS) specification that relaxes resolution and synchronization requirements for playback. Our definitions give a precise meaning to the correctness of a presentation. This specification language will form the basis for a QOS interface for reservation of operating system resources.


An Experimental Study Into The Role Of Routing Flexibility In The Justification Of Advanced Manufacturing Systems, Sanjay Pathak Dec 1993

An Experimental Study Into The Role Of Routing Flexibility In The Justification Of Advanced Manufacturing Systems, Sanjay Pathak

Masters Theses

Increased competition in manufacturing has focused attention on advanced technologies. These costly technologies lead to difficulty in purchase justification using traditional methods. New methods quantify attributes relating to the flexibility of advanced systems. One such attribute is routing flexibility.

This thesis presents results of experiments into evaluation of routing flexibility. The performance of conventional dedicated machinery when compared with that of machines having routing flexibility indicates an advantage of flexible machinery. The thesis indicates a procedure for evaluation of different flexibilities and their comparison with conventional machinery in reality.

An empirical formula is developed that helps in quantifying routing flexibility …


Wildlife Exposure Factors Handbook, Volume I Of Ii, United States Environmental Protection Agency Dec 1993

Wildlife Exposure Factors Handbook, Volume I Of Ii, United States Environmental Protection Agency

United States Environmental Protection Agency: Publications

The Exposure Assessment Group of the Office of Health and Environmental Assessment (OHEA) has prepared the Wildlife Exposure Handbook in support of the Office of Solid Waste and Emergency Response and the Office of Water. The Handbook provides information on various factors used to assess exposure to wildlife. The goals of the project are (1) to promote the application of risk assessment methods to wildlife species, (2) to foster a consistent approach to wildlife exposure and risk assessments, and (3) to increase the accessibility of the literature applicable to these assessments.
The bulk of the document summarizes literature values for …


Synthetic Battlebridge: Information Visualization And User Interface Design Applications In A Large Virtual Reality Environment, Kirk G. Wilson Dec 1993

Synthetic Battlebridge: Information Visualization And User Interface Design Applications In A Large Virtual Reality Environment, Kirk G. Wilson

Theses and Dissertations

With shrinking budgets and fewer personnel, future military training will rely heavily on simulated environments. The goal for this training is to reduce cost while maintaining readiness and unparalleled capability for all levels of military command. This thesis effort, the Synthetic Battle Bridge SBB , provides a real-time simulated environment for military commanders to observe on-going computer simulations of varying participation levels and helps them wring the most from a simulation. The SBB, designed for higher ranking personnel with little time to spend learning how to run the system, must exhibit three capabilities ease-of-use, long-term retention, and adaptability. Based on …


The Afit Multielectrode Array For Neural Recording And Simulation: Design, Testing, And Encapsulation, James R. Reid Jr Dec 1993

The Afit Multielectrode Array For Neural Recording And Simulation: Design, Testing, And Encapsulation, James R. Reid Jr

Theses and Dissertations

A two-dimensional, X-Y addressable, multiplexed array of 256 electrodes (16 x 16) has been fabricated using conventional semiconductor processing techniques. The individual electrodes are 16O microns x 160 microns, approximating the size of the cortical columns; the overall array size is 3910 microns x 3910 microns. The array has been fitted to a chronically implantable package and tested for several days in a simulated neural environment. EEG-like data were collected successfully from individual electrodes in the array. This array improves on a previous design of a 16 electrode (4 x 4) array that was chronically implanted on the cortex of …


Nitric Oxide Production: A Mechanism For Inhibition Of Chlamydia Trachomatis Replication, Bojun Chen Dec 1993

Nitric Oxide Production: A Mechanism For Inhibition Of Chlamydia Trachomatis Replication, Bojun Chen

Electronic Theses and Dissertations

Chlamydia trachomatis (CT) replicates in macrophages, but is inhibited by IFN-$\gamma$ or LPS. IFN-$\gamma$ and/or LPS induced nitrite production in mouse peritoneal macrophages, macrophage cell lines (RAW264.7 and J774A.1) and McCoy cells. Kinetic studies indicated that peak production occurred 48 hours post-treatment. CT infection itself was insufficient to induce nitrite production, but resulted in enhancement of nitrite production in IFN-$\gamma$-treated cells. Treatment with IFN-$\gamma$ or LPS resulted in significant inhibition of CT replication in these cells. Strong correlation between nitrite production and inhibition of CT replication was observed in RAW264.7 and J774A.1 cells (correlation coefficients: $-$0.93 and $-$0.94, p $<$ 0.001). N$\sp{\rm g}$- monomethyl-L-arginine (L-NMMA) specifically inhibited nitrite production and partially reversed inhibition of CT replication in macrophage cell lines. NOS mRNA was measured in RAW264.7 cells by Northern blot and Dot blot hybridization. Strong correlation between NOS mRNA expression and inhibition of CT replication (correlation coefficient: $-$0.97, p $<$ 0.05) was observed. Anti-TNF-$\alpha$ antibody completely neutralized the biological activity of TNF-$\alpha$ secreted by LPS-treated RAW264.7 cells, yet the antibody neither reduced nitrite production nor restored CT replication. Combination of the antibody and L-NMMA significantly enhanced restoration of CT replication. In peritoneal macrophages, inhibition of CT replication induced by IFN-$\gamma$ was partially restored by L-NMMA or anti-TNF-$\alpha$ antibody. In McCoy cells, inhibition of CT replication induced by IFN-$\gamma$ and LPS was not significantly restored by L-NMMA. Great restoration of CT replication by 1 mM L-NMMA was observed in LPS-treated J774A.1 cells (31%), but not in IFN-$\gamma$-treated cells (5%). Our data indicate that (1) NO production is one of the mechanisms for inhibition of CT replication in IFN-$\gamma$-activated peritoneal macrophages and RAW264.7 cells; (2) NO plays a significant role in CT inhibition in LPS-treated macrophage cell lines, but not peritoneal macrophages; (3) TNF-$\alpha$ may be associated with inhibition, but the mechanism(s) may not involve NO production; (4) NO production may not be the mechanism for CT inhibition in McCoy cells treated with IFN-$\gamma$ and LPS.


A Study Of Graphite Peek Composite With Central Elliptical Holes Under Tension, Bill J. Lau Dec 1993

A Study Of Graphite Peek Composite With Central Elliptical Holes Under Tension, Bill J. Lau

Theses and Dissertations

This study investigated the stress-strain response and failure modes of Graphite/Polyetheretherketone (Gr/PEEK) tension specimens containing a central elliptical hole. Both experiments and finite element numerical analyses were conducted. Test specimens included seven layups and three hole geometries; three of each combination were tested. The holes consisted of an ellipse with major axis aligned with the load axis, an ellipse with major axis transverse to the load axis, and a circle. Strain gages were located adjacent to the hole and midway between the hole and tab on all specimens. Strain data was used to plot stress-strain response. The analysis utilized a …


Design Of A Parallel Discrete Event Simulation Coprocessor, Jacob L. Berlin Dec 1993

Design Of A Parallel Discrete Event Simulation Coprocessor, Jacob L. Berlin

Theses and Dissertations

A Parallel Discrete Event Simulation Coprocessor was designed to off- load the synchronization overhead from the processors executing the application. In a multiprocessor architecture, one coprocessor executes the synchronization routines for each host processor. Speedup can be achieved when the host processor executes the application and the coprocessor concurrently executes synchronization routines. The coprocessor uses a programmable microcode control store to guarantee flexibility in the synchronization routines. The coprocessor uses an Extreme Search Associative Memory to support fast Next Event Queue NEQ management. This associative memory uses bit-serial word-parallel search logic to provide 01 insert and retrieval time of events …