Digital Commons Network^™

The Bandwidth Allocation Of Atm Through Genetic Algorithm, Hong Pan

Theses

In this thesis, we develop an optimization method based on Genetic Algorithm to achieve the bandwidth allocation of ATM network. In Broadband Integrated Service Digital Network (BISDN), the Asynchronous Transfer Model (ATM) is already adopted as the transfer standard by CCITT. ATM is a high-bandwidth, low-delay, fast-packet switching and multiplexing technique. Using ATM technique, we can flexibly reconfigure the network and reassign the bandwidth to meet the requirement of all types of services. As an effective optimization method, Genetic Algorithm(GA) is applied to implement the bandwidth allocation of ATM. GA is a class of search algorithm based on the mechanics …

Dual Token Ring Lan Performance, Pratap S. Pasupuleti

Theses

A simulation model to analyze the performance of a dual token ring LAN is developed. The performance measures throughput, average packet delay and maximum delay per packet are obtained. System performance is analyzed for different loads, number of stations, and packet lengths. The performances of token ring LANs with a conventional structure and a dual ring structure are compared for both uniform packet sizes and a case with mixed packet sizes. In the uniform packet size case, the dual ring delays were lower at equivalent throughput because of propagation delay effects. In the mixed packet size case the maximum delays …

A Study Of Biological Dentrification Of Munition Wastes, Sonia R. Venugopal

Theses

Kinetics of denitrification were studied using a consortium from the Lawrence, Kansas municipal treatment plant. Experiments were conducted in the batch mode, under controlled oxygen and pH conditions. It was found that the Monod model can successfully perdict the experimental results of nitrate depletion. It was also found that when the pH is maintained at values between 7.0 and 8.5, nitrate can be treated in a batch mode without having any significant nitrite presence in the reactor. The experimentally determined kinetic parameters were used in preliminary calculations for sizing a sequencing batch reactor (SBR). An existing mathematical model for the …

A Multimode Index Detecting Sensor For Use In Plastic Concrete, Qiyu Chen

Theses

This thesis describes a microcomputer-based measuring system using a laser diode source, a fiber optic sensor and a microcomputer DMA interface to test and analyze the entrained percentage of air in concrete.

The principle of refraction and reflection of light in optical fibers is applied to detection of air bubbles. Reflected light intensity signals are detected and transferred through a DMA interface to a laptop computer. Analysis of reflected light intensity produces a measurement of the air content of fresh concrete. Accuracy of the system is evaluated through extensive laboratory and field trials.

Novel Way Of Sub-Carrier Coherent Detection And Clock Recovery In Fiber-Optic Communications, Narayan Gehlot

Theses

We experimentally demonstrate a novel concept for recovery of a Sub-Carrier and Timing Clock in fiber-optic communication systems using a Wavelength Division Multiplexing technique. The idea is to send a low radio frequency (RF) as a reference pilot from the transmitter to the receiver on a separate laser using the principle of Wavelength Division Multiplexing (WDM). This low frequency signal is taken to be a subharmonic of the subcarrier used to carry information and intensity modulate another laser. Such approach will be expected to generate at the receiver a local oscillator in high coherence with the subcarrier.

We show that …

Coexistence Of Three Pure And Simple Competitors In Four Interconnected Bioreactors, Ming Wu

Theses

It is known that a homogeneous environment having invariant inputs cannot allow for steady state coexistence of any number of pure and simple competitors. However, it has been proven that two pure and simple competitors can coexist at a steady state in two interconnected chemostats, if the conditions are such that they allow a different species to grow faster in each one of the two vessels. It has been also shown that three pure and simple competitors cannot coexist in three interconnected chemostats, even if the conditions are such that a different population could grow faster (have the competitive advantage) …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, January 1991, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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

Summer 1991, 90.9 Wmpg Fm

WMPG Program Guides

Newsletter format.

Santa Clara Magazine, Volume 33 Number 2, Winter 1991, Santa Clara University

Santa Clara Magazine

10 - GROWING UP ADOPTED Santa Clarans who have adopted children or are adopted discuss their experiences with interracial adoption and talk about the identity crisis years most adoptees face. By Susan Frey

16 - WHAT YOUR DOCTOR DOESN'T KNOW CAN KILL YOU A small but growing number of doctors around the world are turning to biological medicine to treat their patients with cancer and other serious diseases. By Michael Sheehan '77

20 - SCU's FATHER GOOSE When John Drahrnann shepherds undergraduates through the academic maze, he often counsels their parents as well. By Thomas F. Black and Maureen Mclnaney …

Peripheral Nerve Bridges For Central Nervous System Regeneration, Silvio Varon, Theo Hagg, H. Lee Vahlsing, Marston Manthorpe

Cells and Materials

A neuronotrophic hypothesis for the adult central nervous system (CNS) has been increasingly supported by in vivo studies of Nerve Growth Factor (NGF) impacts on adult rat CNS cholinergic neurons. We have extended these investigations to NGF effects on cholinergic axonal regeneration in an adult rat septo-hippocampal model. A fimbriafornix lesion deprives the dorsal hippocampal formation (HF) of its cholinergic afferents and provides a cavity into which sciatic nerve segments can be implanted to serve as regeneration bridges from septum to HF. Septa! cholinergic fibers enter and course through fresh cell-containing nerve bridges to attain a maximal number by the …

Deposition And Resorption Of Calcified Matrix In Vitro By Rat Marrow Cells, J. E. Davies, R. Chernecky, B. Lowenberg, A. Shiga

Cells and Materials

Rat bone marrow derived cells were cultured using a-Minimal Essential Medium supplemented with antibiotics, ascorbic acid and !3-glycerphosphate in the presence of 10-8M dexamethasone, on polystyrene and hydrophilic fluorocarbon substrata for periods of 2 - 4 weeks. During this time, a large yield of bone nodules was achieved and the elaborated tissue was examined by both scanning and transmission electron microscopy. The matrix produced by the cells contacting the underlying substratum was an afibrillar, globular, calcified material which formed a layer approximately 0.5μm thick. The calcium and phosphorus content of this material was confirmed by energy dispersive X-ray dot mapping …

A Versatile, Low Toxicity Glycol Methacrylate Embedding Medium For Use In Biological Research, And For Recovered Biomaterials Prostheses, Peter O. Gerrits, Bernhard Eppinger, Harry Van Goor, Richard W. Horobin

Cells and Materials

Methods for preparing standardized glycol methacrylate (GMA) based embedding media for use in light microscopy in a rational, precise and reproducible manner are described. The application of these procedures resulted in a versatile, low toxicity GMA embedding medium.

GMA embedding medium and resin blocks were tested utilizing a variety of physico-chemical techniques, namely: gas chromatography, determination of the maximum temperature reached during polymerization, the time taken to reach the maximum temperature, hardness testing, determination of the glass transition temperature, and measurement of the dimensional changes following section stretching and mounting at various temperatures. Data obtained from these techniques enabled a …

Spring 1991, 90.9 Wmpg Fm

WMPG Program Guides

Newsletter format.

A Comparative Study Of Bovine Pericardium Mineralization: A Basic And Practical Approach, Branko B. Tomazic, Chakwan Siew, Walter E. Brown

Cells and Materials

The biomineralization of bovine pericardium (BP) heart valve bioprostheses was investigated by simulation of the process under in vitro and in vivo conditions. The nature and composition of calcific deposits that formed in human heart valve bioprostheses were compared with the mineral formed on BP discs immersed in a calcifying medium or subcutaneously implanted into Sprague-Dawley rats. The early stage of experimental biomineralization in vitro took place on the surface only, while in vivo deposition appeared to be intrinsic, as documented by histological cross sections. The chemical composition of the initial mineral phase formed under in vitro conditions had a …

Preservation Of The Cell-Biomaterial Interface At The Ultrastructural Level, J. M. Schakenraad, J. A. Oosterbaan, E. H. Blaauw

Cells and Materials

Studying the tissue-biomaterial interface at the ultrastructural level is not without problems. Dissolution of the biomaterial in one of the dehydration or embedding media causes holes and shatter during sectioning or dislodgement of the biomaterial. The fine tuning of the hardness of both biomaterial and embedding medium, as well as the introduction of butyl-2,3- epoxypropylether as an intermediate between the dehydration series and the Epon resin , improving the impregnation , will solve many of the problems mentioned. With this improved technique good results were obtained with materials ranging from teflon, poly(Lactic acid) and polyurethanes to tissue culture polystyrene. No …

Tailwater Recovery Demonstration Program Study, Doug Welch, Tim O'Halloran, Stuart Styles

BioResource and Agricultural Engineering

No abstract provided.

Surface Modification Of Polymers To Permit Endothelial Cell Growth, C. James Kirkpatrick, Detlef Mueller-Schulte, Marc Roye, Guenter Hollweg, Claudia Gossen, Horst Richter, Christian Mittermayer

Cells and Materials

The interaction between endothelial cells (EC) and polymers has become relevant to medicine as a result of attempts to improve the biocompatibility of vascular prostheses. In man, endothelialization is minimal, so that vascular surgeons have attempted to pre-seed vascular grafts with autologous EC. The poor results of EC seeding of commonly used materials for vascular grafts, such as expanded polytetrafluoroethylene (ePTFE) or woven polyester (Dacron) has led to attempts to modify the surface of these and other polymers. Three principal modification techniques have been employed : 1. adsorption of bioactive molecules from applied solutions. Examples are fibronectin, collagen types I …

The Calendar - January 1991, Nova University

The Calendar

No abstract provided.

Content And Strategies For Teaching Computer-Aided Drafting, Kurt Henry Becker

Engineering Education Faculty Publications

No abstract provided.

Evaluation Of The Images Of Specular Microscopy Of The Cells On Implanted Intraocular Lenses In Vivo, Kiyoshi Okada, Keiko Takahashi, Hiroaki Sagawa, Kuniomi Abe

Cells and Materials

Specular microscopy , an optical method to study the anterior segment of the eye, was applied to observe the cells on implanted intraocular lenses in vivo. The images from specular microscopy were evaluated by comparing the morphology of the same cells on intraocular lenses implanted in rabbit eyes by specular microscopy , light microscopy and scanning electron microscopy (SEM). The time lapse study in living human eyes and the optical evaluation of jts interference images were performed to elucidate its image formation.

The same giant cells, as observed in vivo by specular microscopy, proved to be multinucleated cells. It …

Transformation Of 1-Aminonapththalene At The Surface Of Smectite Clays, Calvin C. Ainsworth, Bruce D. Mcveety, Steven C. Smith, John M. Zachara

United States Department of Energy: Publications

One-aminonaphthalene is sorbed onto the Na-saturated smectite clays, montmorillonite and hectorite, by cation exchange. In the presence of Fe³⁺ either in the clay structure or on the clay surface, sorption is followed by the formation of a blue-colored complex, with the continuous disappearance of aminonaphthalene from solution and the clay surface. The rate of aminonaphthalene disappearance decreases as pH increases. With time, four major products that appear to be structural isomers of N(4- aminonaphthyl)-1-naphthylamine are produced. A simplified model of this transformation is suggested to be the oxidation by Fe³⁺ of sorbed aminonaphthalene forming a radical cation-clay complex. …

What To Look For And Why When Buying A Telecommunications Switch

ACUTA: Other Publications

There are three characteristics of institutions of higher education that have a strong

impact on telecommunications:

. Campus Environment

. Multiple Service Populations

. Limited Budgets

Each characteristic translates into requirements for an effective telecommunication

system.

To Serve the Campus Environment

A campus is usually the first image associated with the word "college" or "university." Typically, institutions of higher education are housed in several buildings which may be fairly close together, or spread over some distance, perhaps reaching across a city or even a state.

To serve the campus user, a system must provide feature transparency, regardless of location. Small …

Surface Mapping And Automatic Tool Path Generation, Labiche Ferreira

Retrospective Theses and Dissertations

With the use of machine vision systems in the manufacturing cycle of a product, the lead time for producing the final product has been substantially reduced. Efforts in the past have aimed at automating the tasks right from the drawing board stage to final production of the product. Such technologies include CAD, CAM, and CAPP. However the task of tool path (NC code) generation has not yet been fully automated. In the current techniques, the user plays a crucial role in the NC code generation process. There is an increasing trend for using machine vision systems in the fabrication of …

Photorefractive Materials For Optical Signal Processing, William B. Lawler

Retrospective Theses and Dissertations

The optical response of the photorefractive crystals KNbO₃:Ta, KNbO₃:Fe, LiNbO₃:Fe, and nominally pure BaTiO₃ is investigated. In the experiment, a holographic grating is built in the crystal under investigation via a two-wave mixing scheme that utilizes the signal-processing capacities of two acousto-optic Bragg cells. The dynamic interaction of the Bragg cells with the photorefractive grating causes a heterodyned RF signal to appear on the output laser beam, enabling the real-time, direct measurement of the amplitude and phase of the space-charge fields in the crystal. Experimental results are presented for the amplitude and phase …

Acuta Enews January 1991, Vol. 20, No. 1

ACUTA Newsletters

In This Issue

ECCI founder honored

Pocket phone test at UGA

Giving pays off for Emory

Digitizing X-rays

Illicall lists rates

Party Line

Enhancing Soil Conservation Practice Adoption With Targeted Educational Programs, Elbert C. Dickey, David P. Shelton, Paul J. Jasa

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Two independent, but closely related, grant funded educational programs were developed and implemented to reduce soil erosion in selected areas of eastern Nebraska. Traditional extension programming methods as well as other more non-traditional approaches were used extensively to enhance soil conservation practice adoption. In one program, encompassing 220 000 ha (540,000 acre) of cropland, annual soil erosion was reduced by 2.3 million t (2.5 million ton) and annual fuel savings of 1.5 million L (390,000 gal) were achieved through a reduction in the number of tillage operations. In the second project, more than 93 000 m (305,000 ft) of terraces …

Center For Computer And Information Sciences 1991-1992 Catalog, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Center For Computer And Information Sciences Doctor Of Science In Computer Science 1991-1992, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

A Mathematical Model Of A Sealed Nickel-Cadmium Battery, Deyuan Fan, Ralph E. White

Faculty Publications

A mathematical model for the charge and discharge of a sealed nickel-cadmium (Ni-Cd) battery is presented. The model is used to study the effect of transport properties of the electrolyte and kinetic parameters of the electrode reactions on the cell performance during the charge and discharge period. The model can also be used to demonstrate the changes of cell performance during cycling. Some comparisons between model predictions and experimental results indicate that the model predictions appear to fit the experimental data well. Sensitivity analyses illustrate that the sealed nickel-cadmium battery operates under activation control. It is also shown theoretically that …

Precipitation, Inter-Event Dry Periods, And Reuse Design Curves For Selected Areas Of Florida, Martin Wanielista

BMP Trains Research and Publications

No abstract provided.