Digital Commons Network^™

Experimental Study Of The Rise Of A Large Sphere In A Vibrated Bed Of Monodisperse Spheres, Loic Vanel

Theses

As a simplified way to study size segregation mechanisms, the rise of a single large sphere in a vibrated bed of smaller monodisperse spheres is investigated. The time it takes for the ball to rise from the bottom of the bed to the surface is measured in a very wide range of vibration amplitude, frequency and acceleration. Rise regimes are identified and are classified according to the macroscopic behaviors displayed by the granular bed: heaping, convection without heaping and crystallization. The influence of the large sphere's size on the rise velocity is described. The scaling features of the vibration amplitude …

Macrophage Response To Polymethylmethacrylate Particles, Stephen M. Horowtiz

Cells and Materials

This paper reviews studies performed by this laboratory involving the macrophage response to implant particles. Through the development of a tissue culture model, we have studied the events which occur following macrophage phagocytosis of bone cement particles, the released mediators and cell interactions which may ultimately lead to bone resorption, and the inhibition of this process with the use of pharmaceutical agents. This is divided into the following sections: Histologic response of macrophages to cement particles I toxicity I and mediator release, the effects of particle size and composition on mediator release by macrophages, macrophage I osteoblast interactions, macrophage I …

Nusselt Number For Flow Perpendicular To Arrays Of Cylinders In The Limit Of Small Reynolds And Large Peclet Numbers, Ashok S. Sangani, Wei Wang

Biomedical and Chemical Engineering - All Scholarship

The problem of determining the Nusselt number N, the nondimensional rate of heat or mass transfer, from an array of cylindrical particles to the surrounding fluid is examined in the limit of small Reynolds number Re and large Peclet number Pe. N in this limit can be determined from the details of flow in the immediate vicinity of the particles. These are determined accurately using a method of multipole expansions for both ordered and random arrays of cylinders. The results for N/Pe^1/3 are presented for the complete range of the area fraction of cylinders. The results of numerical simulations for …

Winter/Spring 1997, 90.9 Wmpg Fm

WMPG Program Guides

Newspaper format

Summer 1997, 90.9 Wmpg Fm

WMPG Program Guides

"WMOG Bares it All! Live Broadcasts in Public"

Sintered Carbonate Apatites As Bone Substitutes, Yutaka Doi

Cells and Materials

Sintering of carbonate apatites was investigated and the usefulness of sintered specimens as bone substitutes was evaluated in vitro and in vivo. Osteoclasts appeared to be capable of resorbing sintered carbonate apatite, which was as soluble as deproteinated bone and much more soluble than sintered hydroxyapatite in weak acids. In skull defects of Wistar rats, sintered carbonate apatite particles resorbed to an appreciable extent, but the rate of resorption did not exceed that of new bone formation. At 4 weeks after implantation the defects were filled almost completely with new bone that compared favorably with the host bone. These …

Detachment Of Human Endothelial Cells Under Flow From Wettability Gradient Surfaces With Different Functional Groups, T. G. Ruardy, H. E. Moorlag, J. M. Schakenraad, H. C. Van Der Mei, H. J. Busscher

Cells and Materials

In this study, the position bound adhesion, spreading and detachment under flow of human umbilical cord endothelial cells (HUVEC) was studied on a dichlorodimethylsilane (DDS), dimethylocta-decylchlorosilane (DOCS) and tridecafluor-1,1,2,2-tetrahydrooctyl-1-dimethylchlorosilane (TFCS) wettability gradient on glass. Gradient surfaces were prepared by the diffusion method and characterized by the Wilhelmy plate technique for their wettability and by X-ray photoelectron spectroscopy (XPS) for their chemical composition. Quantitative analysis of the cellular response on the wettability gradient surfaces showed that the position bound cellular response was influenced by wettability for each type of gradient in a different way. On DDS-wettability gradients, cells withstood flow best …

Biofilms In Dental Unit Waterlines: Ultrastructural And Cytochemical Analysis, J. Barbeau, C. Avezard, E. Faucher, S. Zalzal, A. P. Prévost

Cells and Materials

Dental unit waterlines are heavily colonized by bacteria which contaminate the water used to perform intra-oral, and sometimes invasive, procedures. There is little information on the nature of the biofilm colonizing the flexible plastic tubing used to supply water to the different handpieces. We have therefore undertaken quantitative microbial analysis and ultrastructural studies of these biofilms by direct counting with the epifluorescent filter technique and by transmission and scanning electron microscopy after staining with ruthenium red and periodic acid-thiosemicarbazide-silver proteinate to visualize the composition and the distribution of exopolysaccharides and intracellular polysaccharides. The biofilm was revealed as a non-uniform structure …

Osteoclast Differentiation In Cocultures Of Chondrogenic Cell Line Rcj 3.1c5.18 And Mouse Or Rat Bone Marrow: Dependence On Culture Substrate And Association With Alkaline Phosphatase Positive Marrow Stromal Cells, G. I. Anderson, J. N. M. Heersche

Cells and Materials

We investigated the formation of tartrate-resistant acid phosphatase positive (TRAP+) colonies and multinucleated cells (MNCs) in rat and mouse marrow cultures alone and cocultured with the chondrogenic cell line, RCJ3.1C5.18 on different substrata. In mouse marrow cultured in 35 mm dishes, few TRAP+ MNCs developed, while in rat marrow cultures, many TRAP+ MNCs, which possessed calcitonin receptors and resorbed bone, developed. In both rat and mouse cultures, TRAP+ MNC first appeared at Day 4 and grew in number up to Day 8. When both marrows were cocultured with RC3.1C5.18 cells, TRAP+ colony numbers increased relative to marrow alone. In marrow …

Design And Implemetation Of Internet Mail Servers With Embedded Data Compression, Alka Nand

Theses Digitization Project

No abstract provided.

Assessment Of Cased-Borehole Seals Using An Ultrasonic Method, Nazli Yesiller, Craig H. Benson, Tuncer B. Edil, James Klima

Civil and Environmental Engineering

Tests were conducted in Wisconsin from 1994 through 1996 in several boreholes using an ultrasonic method that was developed at the University of Wisconsin-Madison to assess the integrity of annular seals. Initially, three model boreholes simulating monitoring wells were installed to evaluate the effectiveness of the ultrasonic method. Different types of seals were placed around the casings and defects were purposely introduced in the seals to test the ultrasonic method. The ultrasonic method was effective for detecting the presence of different types of seals and defects and also the changes in the condition of seals with time. Then tests were …

Fractals, Surface Roughness, And Fracture Toughness Of Dental Composite And Unfilled Resin Fracture Surfaces, James L. Drummond

Cells and Materials

The intent of this project was to evaluate whether or not there exists a correlation between fractal dimension, surface roughness, and fracture toughness of an unfilled resin and a filled composite. The fracture surfaces of the unfilled resin and the filled composite were examined using atomic force microscopy (AFM) and a surface roughness measuring device. The specimens examined were aged in distilled water or air at 37°C for up to 12 months. Line scans of 1.4 µm for the atomic force microscope and 0.25 mm for the surface analyzer across the fracture surface were conducted on each specimen. Comparisons …

Bone Marrow Cell Colonization Of, And Extracellular Matrix Expression On, Biodegradable Polymers, C. E. Holy, M. S. Shoichet, J. E. Davies

Cells and Materials

Poly(DL-lactide-co-glycolide)s (PLGAs) have been proposed as substrata for bone tissue engineering. In the experiments reported herein, we sought to identify the optimum lactide to glycolide ratio, from the series 85:15, 75:25, 50:50, or poly-(DL-lactide) (PLA), for the elaboration of bone matrix by cultured rat bone marrow cells (RBMC) on two-dimensional substrates. Having identified PLGA 75:25 as the optimum for bone matrix elaboration by RBMC, we produced three dimensional foams from this copolymer. For the two dimensional substrata, glass coverslips were spin-coated with one of the PLGAs, or PLA. Cultures were maintained for two weeks. We employed a new technique to …

Multilevel Block Coded Modulation With Unequal Error Protection, Robert H. Morelos-Zaragoza, Marc P. C. Fossorier, Shu Lin, Hideki Imai

Faculty Publications

Multilevel block coded modulation (BCM) schemes with unequal error protection (UEP) are investigated. These schemes are based on unconventional set partitions that greatly reduce the error coefficients associated with multi-stage decoding of conventional BCM, at the expense of smaller intra-set distances.

The Airline Quality Rating 1997, Brent Bowen, Dean Headley, Uno Aviation Institute

Faculty Books and Monographs

UNOAI Report 97-9

The Airline Quality Rating (AQR) was developed and first announced in early 1991 as an objective method of comparing airline performance on combined multiple factors important to consumers. Development history and calculation details for the AQR rating system are detailed in The Airline Quality Rating 1991 issued in April, 1991, by the National Institute for Aviation Research at Wichita State University. This current report, Airline Quality Rating 1997, contains monthly Airline Quality Rating scores for 1996. Additional copies are available by contacting Wichita State University or University of Nebraska at Omaha. The Airline Quality Rating 1997 is …

Concatenated Multilevel Coded Modulation Schemes For Digital Satellite Broadcasting, Robert H. Morelos-Zaragoza, Hideki Imai

Faculty Publications

The error performance of bandwith-efficient concatenated multilevel coded modulation (MCM) schemes for digital satellite broadcasting is analyzed. Nonstandard partitioning, multistage decoding, and outer Reed-Solomon (RS) codes are employed to provided unequal error protection capabilities.

Quantitation Reference Compounds And Voc Recoveries From Soils By Purge-And-Trap Gc/Ms, Brian Schumacher, Steven Ward

United States Environmental Protection Agency: Publications

Unquantified volatile organic compound (VOC) losses occur in every phase of VOC determination including sample collection, transport, storage, preparation, and analysis. Current quality assurance/quality control measures, such as surrogate spikes and internal standards, do not account for losses that occur during sample handling nor do they account for soil matrix effects. An alternate approach, the quantitation reference compound (QRC) approach, is presented that involves direction injection of the QRCs onto the soil matrix to account for any matrix effects and losses during subsequent processing steps prior to sample analysis. Final VOC quantitation is based on the QRC instead of the …

Diophantine Type Fractional Derivative Representation Of Structural Hysteresis, Part Ii: Fitting, Computational Mechanics, Jerzy T. Sawicki, Joe Padovan

Mechanical Engineering Faculty Publications

Part I of this series introduced the diophantinized fractional model and the decompositional formulation. The various important properties of fractional continuum formulation and its decomposed version were developed. In Part II the dynamic properties of the diophantine representation are investigated. The model fitting scheme will be developed to handle an arbitrary frequency dependent structural hysteriesis. This is followed up with the results of benchmark studies which demonstrate the effectiveness of fitting.

A Novel In Vitro Model To Study The Calcification Of Biomaterials, Q. Liu, J. Weng, J. G. C. Wolke, J. R. De Wijn, C. A. Van Blitterswijk

Cells and Materials

A novel in vitro model based on a solution mainly composed of sodium, calcium, chloride and phosphate ions, was developed to study the calcification of biomaterials at near physiological conditions. This model, due to its ability to quickly calcify the tested materials, is called Accelerated Calcification Solution (ACS). Polyactive ™ 30170, Polyactive™ 70/30 and its composites with nano-apatite were used as testing materials because of their known calcification behaviour. The results showed that Polyactive™ 70/30 and its composites could calcify in ACS in a relatively short period, while the polymer without filler failed to induce calcium phosphate precipitation in more …

Telecourse And Traditional Computer Applications : Exploring The Impact Of Review Sessions, Carol Odette Bourke

Retrospective Theses and Dissertations

The purpose of the study was to explore the effects of review sessions on student achievement and retention in a computer applications course taught by televised distance learning and traditional instruction. Identified within the study were method of instruction, review, and grades in televised and traditional computer applications courses. A quasi-experimental design was used to measure the effects of review sessions on student achievement and retention in computer applications classes. Intact classes were used to form the 4 groups used in this study. Randomization was limited to choices students made in registering for the classes. The control groups for this …

Impulse, Kate Gundvaldson, Cathy Nelson, Jennifer Widman

Impulse (Jerome J. Lohr College of Engineering Publication)

Features:
[Page 2] Engineering designated Center of Excellence in Technology
[Page 4] ENTRE class acts as 'Counterpart' to small business
[Page 5] Farm building construction studied
[Page 6] Experimental instrumentation aims to create ideal earth imaging
[Page 8] Svec celebrates 80th birthday
[Page 10] Research improves meat safety
[Page 10] Engineering Extension offers OSHA course
[Page 11] Rural water research helps small towns
[Page 11] Soybean plant visited
[Page 12] UITS nets outstanding rating
[Page 13] Shin offers outreach
[Page 14] German profs visit SDSU
[Page 15] Chinese prof exchanges ideas with American colleagues
[Page 16] U.S. News & World …

Review Of Pit Nucleation, Growth And Pitting Corrosion Fatigue Mechanisms, Tarun Goswami, D. W. Hoeppner

Biomedical, Industrial & Human Factors Engineering Faculty Publications

This paper presents a review of the state of the art developments in the pitting corrosion fatigue of aircraft structural materials. Mechanisms that govern the nucleation and growth of pitting and corrosion fatigue (CF) are briefly addressed. Some of the developments made in the author's laboratories in proposing the fretting induced pit nucleation and growth mechanisms, analysis of the hidden corrosion constituents in fuselage joints and pitting corrosion fatigue crack growth (PCFCG) model are elucidated. An epistemology of the topic is presented which will be of assistance to the community working in this area.

Simulating Migration Of Contaminated Sediments In The Lower Columbia Slough System, Min Chen

Dissertations and Theses

Recent screening-level risk assessment of Slough sediments initiated by the City of Portland identified five contaminated areas in the Slough as posing the greatest potentially significant risks to human health. These five areas were recommended for accelerated remedial action.

But one question remains, does the sediment contamination at these hot spots change over time in response to the changing Slough hydrodynamics? Specifically, will the contamination move or spread even before remedial action is taken? Will they still be there by the time when potential remedial action is taken? Will any new hot spots be created in response to nonuniform transient …

The Treatment Of Vegetable Processing Waste Water Using A Pilot Scale Sequencing Batch Reactor Activated Sludge Process, Peter Hassett

Theses

The SBR process is a discontinuous, unsteady state process and has developed popularity in many countries assisted by reliable control technology for example programmable logic control. A typical SBR installation achieves equalisation, aeration and clarification of batches of wastewater on a timed sequence in one basin. This is in contrast to a volume sequenced process such as the conventional continuous stirred tank reactor where individual treatment objectives are met in separate basins. Advantages include, flexability, minimum energy input, consistent effluent quality and inhibition of filament organism growth by properly controlling substrate concentration and aeration sequences. Nitrification, denitrification and Bio-P removal …

Adsorption And Desorption Of Phosphorus And Nitrogen By Immersed Stalks, John E. Gilley, B. Eghball, David B. Marx

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Adsorption and desorption of phosphorus (P) and nitrogen (N) by stalk residues may influence the concentrations of P and N in runoff. A laboratory study was conducted to measure the effects of P and N constituents in solution on adsorption and desorption of P and N by corn, soybean, and wheat stalk residues. Experimental variables included type of stalk material (corn, soybean, and wheat), inorganic nutrients in solution (PO₄-P and NO₃-N; PO₄-P and NH₄-N; NO₃-N and NH₄-N; and PO₄-P, NO₃-N, and NH₄-N), …

Corrosion Fatigue Crack Growth Behavior Of Aircraft Materials, Tarun Goswami, D. W. Hoeppner

Biomedical, Industrial & Human Factors Engineering Faculty Publications

The effects of test parameters on the corrosion fatigue crack growth behavior of structural materials have been examined in this paper. Test parameters such as stress ratio, frequency, hold time, temperature, pH level of the media, and other parameters are known to alter the corrosion fatigue crack growth rates in structural materials. Numerous laboratory test variables that affect the crack growth and/or corrosion growth rates, which in an operating environment of an aircraft are not characterized, are reviewed. A summary of such information may help determine the inspection intervals of the new and aged airplanes, perform the inspections, and develop …

Doctoral Degree Programs School Of Computer And Information Science 1997, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

An Analysis Of Printed Circuit Boards During Reflow Soldering., Paul Barry

Theses

Electronic manufacturing is currently one of the fastest growing industrial areas. This is due to the rapid advances in the computer and telecommunications sectors. Due to these advances, new surface mount devices have been developed to achieve greater miniaturisation at lower costs. As a result, a new surface mount technology has been developed to mount these devices onto printed circuit boards. However, problems exist with aspects of this process, principally open solder joints which result from circuit board warpage. The aim of this thesis is to undertake a) both an experimental and theoretical investigation of the reflow solder process and …

Ellipsometric And Raman Spectroscopic Study Of Thermally Formed Films On Titanium, E. Hristova, Lj. Arsov, Branko N. Popov, Ralph E. White

Faculty Publications

Thermal films on titanium surfaces were formed by heating titanium samples in air at atmospheric pressure. The optical constants, thickness, and structure of the formed films at various temperatures and times of heating were investigated by ellipsometry and Raman spectroscopy. The complex index of refraction and the thickness of generated films were determined by comparing the experimental loci and obtained by ellipsometric measurements with theoretical computed vs. curves. It was found that the thickness in homogeneity and porosity of formed films increase with increasing temperature and the duration of the thermal treatment. Beyond a certain critical temperature, the appearance of …

The Effects Of Organic Compounds On Inhibition Of Hydrogen Permeation Through A Mild Steel Membrane, H. A. Duarte, D. M. See, Branko N. Popov, Ralph E. White

Faculty Publications

The effectiveness of 5-(4-pyridyl)-2,7-nonadiene, and 1 phenyl-2-propyn-ol (PP) on inhibition of the hydrogen evolution reaction on a 1010 steel membrane and on the degree of hydrogen ingress into the membrane was determined. Hydrogen evolution rates and permeation currents were monitored as a function of time at different applied potentials. In the presence of 0.5 g/liter PP in the electrolyte, the hydrogen discharge and permeation current density were inhibited by 98 and95%, respectively.