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Micro-Sprinkler And Fan Cooling For Dairy Cows: Practical Design Considerations, Larry W. Turner, Richard C. Warner, John P. Chastain Jun 1992

Micro-Sprinkler And Fan Cooling For Dairy Cows: Practical Design Considerations, Larry W. Turner, Richard C. Warner, John P. Chastain

Agricultural Engineering Extension Publications

Research and on-farm demonstrations have shown that micro-sprinklers, spray jets and fan cooling systems can be effective in relieving heat stress in dairy cows under hot, humid conditions. Based on these results, many dairymen are considering installing sprinkler and fan cooling. Several Kentucky dairymen have already installed sprinkler cooling systems, but they could improve their performance by modifying them to take into account the principles involved and the components used in sprinkler and fan cooling.


New In Vivo And In Vitro Techniques For Quantification Of Lateral Force Levels That Cause Implants To Fail : A Progress Report On Monkey Research, V. Leroy Leggitt Jun 1992

New In Vivo And In Vitro Techniques For Quantification Of Lateral Force Levels That Cause Implants To Fail : A Progress Report On Monkey Research, V. Leroy Leggitt

Loma Linda University Electronic Theses, Dissertations & Projects

Two new techniques for quantification of forces generated by an expansion screw apparatus placed between pairs of cylindrical endosseous titanium implants are described, along with preliminary data gained from their use in Macaca rhesus monkeys. Strain gages were bonded to the expansion apparatus and were calibrated either directly by micro load cell, or indirectly by Instron Machine to reflect the applied force.

Immediate loads of up to 6 kilograms have been applied to the implants with no increase in mobility as verified by a Periotest device. No previous studies on the orthodontic uses of implants have evaluated in vivo forces …


Disinfection Of Wastewater Using Ultraviolet Radiation, David L. Klemm May 1992

Disinfection Of Wastewater Using Ultraviolet Radiation, David L. Klemm

Theses

The disadvantages associated with the use of chlorine for disinfection, in conjunction with improvements in ultraviolet radiation disinfection technologies have led to the recent increased use of ultraviolet radiation to provide disinfection of effluents from wastewater treatment plants. The theory of ultraviolet radiation and the engineering design of the ultraviolet disinfection system are discussed in depth.

The operational history and records of two wastewater treatment plants that use ultraviolet radiation for disinfection were analyzed in an attempt to develop correlations on the factors that affect ultraviolet radiation disinfection efficiency and to investigate as to whether disinfection with ultraviolet radiation is …


Effect Of 2,3-Butanedione Monoxide On Whole-Cell Potassium Channel Currents In Rat Single Myocytes, Youliang Zhou May 1992

Effect Of 2,3-Butanedione Monoxide On Whole-Cell Potassium Channel Currents In Rat Single Myocytes, Youliang Zhou

Theses

The patch clamp technique is a simple procedure which can isolate ion channels on cell membranes. Our previous data have shown that 2,3-Butanedione Monoxime (BDM) could inhibit the calcium current by dephosphorylation of the channel. In this study, the effect of BDM on the potassium channels were investigated with the whole-cell recording method in single myocytes enzymatically isolated from the left ventricle of 3-4 months old rats. Superfusion of myocytes with BDM elicited a dose dependent decrease of the outward transient potassium current. BDM with concentrations of 5, 20 and 50 mM reduced the maximal peak potassium current by 7.3 …


Kinetic Measuremenmt Of Decomposition Of Aniline, 2,4-Dichlorophenol And 1,2,4-Trichlorophenol Using A Calorimetric Method, Ming-Chin Chang May 1992

Kinetic Measuremenmt Of Decomposition Of Aniline, 2,4-Dichlorophenol And 1,2,4-Trichlorophenol Using A Calorimetric Method, Ming-Chin Chang

Theses

Biological treatment techniques for detoxification of toxic organic compounds have been studied and applied for many years. There are many research and commercial applications proving that the biological method is more economic and efficient than the other treatment methods.

The traditional biomass measurements are time-consuming tasks. Researchers have intended to develop a simpler, faster, and also accurate method for determining the bioactivity. This study has tried to use the microcalorimetric method to monitor the energy productions from the degradation of aniline, 2,4-Dichlorophenol and 1,2,4-Trichlorobenzene. Thereafter, by utilizing the data obtained from the present study, it was possible to compute kinetic …


Evaluating The Homogeneity Of Solidification/Stabilization Treated Waste Soils By Chemical Analysis Method, Mei Liu May 1992

Evaluating The Homogeneity Of Solidification/Stabilization Treated Waste Soils By Chemical Analysis Method, Mei Liu

Theses

Solidification/Stabilization technology has been widely used for waste treatment, especially for heavy metals, non-volatile wastes, radioactive wastes and soils. Homogeneity is a very important criterion for this kind of technology.

This study focuses on the development of a method to evaluate the homogeneity of S/S treated soil. A chemical analysis method, atomic absorbance, is employed to evaluate the distribution of S/S reagent in a soil-cement mixture and thus the uniformity of the soil-cement mixture. Also, a fluorescent tracer method is discussed in this study, which can be used to estimate the homogeneity of the soil-cement surface. The fluorescent tracer method …


Inability Of Phanerochaete Chrysosporium To Degrade Polychlorinated Biphenyls In Sand, Pankaj Pankaj May 1992

Inability Of Phanerochaete Chrysosporium To Degrade Polychlorinated Biphenyls In Sand, Pankaj Pankaj

Theses

The white rot fungus Phanerochaete chrysosporium has been previously found to successfully degrade a wide spectrum of chlorinated aromatic hydrocarbons (some of them in soil or sand matrices). In this research, it was tested if the fungus could also degrade a very recalcitrant class of pollutant, i.e. Polychlorinated Biphenyls (PCBs) in sand at a concentration of 100 ppm (w/w PCB to sand). For this purpose, a number of experiments were performed, in which several operating parameters, such as nutrient concentrations (nitrogen and glucose), amount of initial biomass, aeration, and degree of chlorination of the PCBs were varied. The results obtained …


A Survey Of Electronic Environmental Controllers, Richard S. Gates, Douglas G. Overhults, Larry W. Turner May 1992

A Survey Of Electronic Environmental Controllers, Richard S. Gates, Douglas G. Overhults, Larry W. Turner

Biosystems and Agricultural Engineering Faculty Publications

Sixteen commercially available electronic environmental controllers were evaluated. The units were classified according to enclosure type, analog versus microprocessor based control, power supply, sensors, alarms, control relays and triac output, interval timers, outside temperature feedback, and retail price. An assessment of these controllers indicated several critical limitations in the application of this technology.

The use of integrated controllers for animal production has the potential for substantial improvements in production efficiencies. If the limitations observed in the present controller technology, as represented by this sample, are addressed, industry acceptance of the technology can be accelerated. A uniform standard to address this …


Sprinkler Irrigation-Pesticide Best Management Systems, A. Y. Ranjha, Richard C. Peralta, Robert W. Hill, A. M. Requena, Howard M. Deer, M. Ehteshami May 1992

Sprinkler Irrigation-Pesticide Best Management Systems, A. Y. Ranjha, Richard C. Peralta, Robert W. Hill, A. M. Requena, Howard M. Deer, M. Ehteshami

Civil and Environmental Engineering Faculty Publications

The relative reduction in potential groundwater contamination due to pesticides at several sites in Utah was determined by comparing alternative irrigation system designs, water management practices, and pesticides. Alternative sprinkler irrigation distribution coefficients were used to estimate irrigation application depths. The movement of pesticides through soils following sprinkler irrigations was simulated with a one-dimensional model. Pesticide contamination of groundwater can be reduced by careful selection of pesticides, using properly designed irrigation systems, and improved water management techniques. Procedures for selecting an appropriate sprinkler system design and pesticide are presented. KEYWORDS. Pesticides, Leaching, Sprinkler irrigation, Irrigation depth, Irrigation system design, Soil, …


A Parametric Investigation On Aeroelastic Behavior Of An Airfoil In Steady Flow, Edward J. Feltrop Apr 1992

A Parametric Investigation On Aeroelastic Behavior Of An Airfoil In Steady Flow, Edward J. Feltrop

Opportunities for Undergraduate Research Experience Program (OURE)

A parametric study is performed to investigate the influence of a number of aerodynamic, inertia and damping parameters upon the dynamic response of an elastically-supported rigid wing in steady flow. The dimensionless equations governing the vertical and angular motion of this wing are solved by an interactive computer program which facilitates the systematic analysis of the effects of changes in these parameters upon the dynamic response of the system. This investigation demonstrates the coupling of the vertical and angular motion of the wing, and illustrates the strong influence of damping, spring stiffness, initial spring deflection, and initial angular velocity upon …


Head-Spine Finite Element Computer Model On A Work-Station, Kay F. Schilli Apr 1992

Head-Spine Finite Element Computer Model On A Work-Station, Kay F. Schilli

Opportunities for Undergraduate Research Experience Program (OURE)

In this project, the head-cervical spine finite element computer model has been modified and made portable on the Apollo work-station. The program was developed to aid the researcher in analyzing the simulated behavior of the human spine. The modifications in the computer program have been made in order to utilize the finite element code for continuation of further research.


Instant Centers Of Velocity In A Kinematically Intelligent Blackboard Environment, R. Jeff Fensterman Apr 1992

Instant Centers Of Velocity In A Kinematically Intelligent Blackboard Environment, R. Jeff Fensterman

Opportunities for Undergraduate Research Experience Program (OURE)

This project was part of a continuing expansion of a graphical software environment called "Skimp”, originally developed by Dr. J. K. Nisbett.[l] The final version of this software package will allow the kinematic concepts of an introductory machine dynamics class to be taught exclusively on a blackboard sized projected computer screen. This software package will be used as a teaching aid in the classroom as well as a tutorial for students outside the classroom.

The scope of this project was limited to the concept of instant centers of velocity. This portion is a subroutine accessible during the regular execution of …


Optimization Of Cryopreservation Protocols For Cardiovascular Tissue, Jianfei Hu Apr 1992

Optimization Of Cryopreservation Protocols For Cardiovascular Tissue, Jianfei Hu

Theses and Dissertations in Biomedical Sciences

The purpose of this research was to determine the effects of cryopreservation on the physical, biochemical and cellular aspects of heart valve tissue. The present study demonstrated that radiolabeled proline accumulation provides a quantitative estimate of total cellular metabolic viability. Radiolabeled inulin was demonstrated to be a useful marker for extracellular tissue space. Assessment of metabolic viability of the cellular population of leaflet tissue as a function of procurement and processing revealed that proline accumulation declined with increasing warm and cold ischemic times. Amphotericin B and streptomycin were toxic to the cells. Cefoxitin, lincomycin, polymyxin B, vancomycin and penicillin had …


Neural Network Based Vowel Articulation Training Aid For The Deaf, Andrew E. Beck Apr 1992

Neural Network Based Vowel Articulation Training Aid For The Deaf, Andrew E. Beck

Electrical & Computer Engineering Theses & Dissertations

Teaching the hearing-impaired to speak is both a challenging and rewarding task. Computer-based training aids are valuable teaching tools and complement the speech therapist in the speech training process. We have developed a computer based vowel articulation training aid designed to provide visual feedback for vowel production to the hearing-impaired user. This system transforms speech spectra from a multi-dimensional acoustic space to a two-dimensional phonetic space which is displayed on a computer monitor. The system signal processing includes feature extraction designed to mimic the properties of the human ear, and a transformation to a two-dimensional display space. The dimensionality transformation …


Formant Estimation From Dctc's Using A Feedforward Neural Network, Shubhangi U. Kelkar Apr 1992

Formant Estimation From Dctc's Using A Feedforward Neural Network, Shubhangi U. Kelkar

Electrical & Computer Engineering Theses & Dissertations

Formants are the natural frequencies of the human vocal tract. Existing methods for estimating formants from speech signals are computationally complex and subject to errors for certain type of speech sounds. This thesis describes a method for estimating vowel formant frequencies from Discrete Cosine Transform Coefficients (DCTC's), a form of cepstral coefficients, using a feedforward neural network with back-propagation training. Experimental results are based on a large multispeaker data base. The results are obtained for both a linear transformation and a feedforward neural network with a nonlinear hidden layer. In general, the neural network transformation is superior to the linear …


Transient Overvoltage Testing Of Environmental Controllers, Richard S. Gates, Larry W. Turner, Douglas G. Overhults Mar 1992

Transient Overvoltage Testing Of Environmental Controllers, Richard S. Gates, Larry W. Turner, Douglas G. Overhults

Biosystems and Agricultural Engineering Faculty Publications

The integrated electronic control system will provide a new method for the day-to-day management of environmental control of animal production systems. No standards are currently accepted for transient overvoltage protection of these controllers. To assess the adequacy of existing designs, a test circuit was designed and used for a transient open circuit over-voltage waveform (ANSI/IEEE C62.41-1980) of 16 environmental control units: a maximum spike of 770 V was applied to the power supplies, and a spike up to 100 V was applied to temperature sensor lines. For these relatively mild tests, no failures were noted due to power supply transients, …


Development Of A System For Survey Of Radon Concentration Of The Dayton Area Using A Liquid Scintillation Counter And Analysis Of The Data, Taewon Kim Mar 1992

Development Of A System For Survey Of Radon Concentration Of The Dayton Area Using A Liquid Scintillation Counter And Analysis Of The Data, Taewon Kim

Theses and Dissertations

A system to do a large scale survey was developed. The data obtained from the survey was analyzed using a database. The database incorporated an equation for converting cpm into radon concentration pCi/ℓ). The equation of conversion, protocol for measuring radon concentration, survey form, and a database program were modified (from previous theses) or developed for this thesis. The elution time constant, adsorption time constant, and calibration factor were calculated for equation of conversion. Two surveys were during the course of the thesis. On the first survey, the arithmetic average radon concentration with standard error of the mean was 2.9 …


Spartan: An Instructional High Resolution Land Combat Model, David K. Cox Mar 1992

Spartan: An Instructional High Resolution Land Combat Model, David K. Cox

Theses and Dissertations

This project developed an instructional high resolution land combat simulation model. The purpose of this model is to demonstrate common techniques of modeling used in the present generation of US Army land combat models. This model is stochastic and uses an event scheduling type of discrete event time algorithm. The model represents a maximum of two six-man infantry squads in direct fire combat. The individual soldiers move, search for targets, engage targets, and react to hostile encounters. The data values provided will the model are all. generic and hypothetical. The model is only intended as a demonstration tool and has …


Saber: Airland Combat Training Model Credibility Assessment And Methodology, David L. Scagliola Mar 1992

Saber: Airland Combat Training Model Credibility Assessment And Methodology, David L. Scagliola

Theses and Dissertations

Saber is a theater-level, airland combat training model, designed by a number of computer science and engineering students and faculty at the Air Force Institute of Technology (AFIT). Saber is intended to replace the Agile model, which is currently used at the Air Force Wargaming Center, Maxwell AFB, Alabama for Theater Warfare Exercise (TWX) training purposes. This thesis focuses on the progress made towards generating the Saber training model, its ability to meet the objectives specified by the Wargaming Center, and its ability to represent actual combat. Specifically, this thesis is directed towards characterizing, establishing a credibility assessment, and developing …


The Influence Of Cross-Cultural Differences On The Interpretation And Understanding Of Aircraft Passenger Safety Briefing Cards, Florian G. Jentsch Mar 1992

The Influence Of Cross-Cultural Differences On The Interpretation And Understanding Of Aircraft Passenger Safety Briefing Cards, Florian G. Jentsch

Master's Theses - Daytona Beach

Aircraft passenger safety briefing cards are an important part of passenger safety education aboard commercial aircraft. The cards must be understood by all readers, regardless of age, gender, or culture. Related research indicates that passengers from different cultures might misunderstand the highly specialized instructions on safety cards.


A Computer Based Educational Aid For The Instruction Of Combat Modeling, Richard S. Moore Feb 1992

A Computer Based Educational Aid For The Instruction Of Combat Modeling, Richard S. Moore

Theses and Dissertations

The Air Force Institute of Technology is one of few institutions that teaches combat modeling. Combat models are typically dynamic computer simulations of specialized dynamic processes. Great difficulty exists in portraying these dynamic and recurrent processes with conventional static diagrams. This thesis produced a computer-based instructional aid which presents animated examples of processes common to combat models, demonstrates a simple few-on-few aerial combat model, and encourages student exploration and interaction with these presentations. This aid provides dynamic examples of random number generation, detection processes, target selection, and target destruction. A complete combat model demonstrating a few-on-few air duel is animated …


Computer Numerical Controlled (Cnc) Machining Of Screws And Dies For Plasticating Extruders : Determination Of The Criteria For Implementing Cnc Machining, Nilesh H. Desai Jan 1992

Computer Numerical Controlled (Cnc) Machining Of Screws And Dies For Plasticating Extruders : Determination Of The Criteria For Implementing Cnc Machining, Nilesh H. Desai

Theses

The work of this thesis is dedicated to the manufacturing industry making production equipment to manufacture plastic products. The main theme of the thesis is to determine the criteria for implementing Computer Numerical Control machining to make parts with complex geometries for production equipment.

A small manufacturing company with job shop type of production was chosen as the subject and study of extruder manufacturing process was performed. The various available alternatives of CNC manufacturing units available in the market were chosen and their feasibility examined.

At present a large variety of CNC machine tools are available in the market, offered …


Microstructure Of Mica Glass-Ceramics And Interface Reactions Between Mica Glass-Ceramics And Bone, W. Holand, W. Gotz, G. Carl, W. Vogel Jan 1992

Microstructure Of Mica Glass-Ceramics And Interface Reactions Between Mica Glass-Ceramics And Bone, W. Holand, W. Gotz, G. Carl, W. Vogel

Cells and Materials

This review paper characterizes glass-ceramics containing mica as main crystal phase. The phase formation reactions in dependence of the chemical composition and the microstructure are shown. Microstructure of mica glass-ceramics has been studied by electron replica and scanning electron microscopic (SEM) techniques.

Mica glass-ceramics have previously been developed in Si02-B20rA120rMgO-F--base glasses. The material is machinable because of the precipitation of micas of fluorophlogopite-type. Also, a machinable glass-ceramic for dental applications was developed based on KMg2_5(Si40 10)F2-micas. We developed mica glass-ceramics in the Si02-Al20rMgO-NaiO-K20-F glass system. Phase formation within these glasses was observed by SEM. A double controlled nucleation and crystallization …


The Effect Of Polymethylmethacrylate Bone Cement Vibration On The Bone-Cement Interface, A. M. C. Thomas, D. J. W. Mcminn, M. Haddaway, I. W. Mccall Jan 1992

The Effect Of Polymethylmethacrylate Bone Cement Vibration On The Bone-Cement Interface, A. M. C. Thomas, D. J. W. Mcminn, M. Haddaway, I. W. Mccall

Cells and Materials

Low frequency vibration of polymethylmethacrylate (PMMA) bone cement reduces the viscosity of the cement by shear thinning. The effect of this low frequency vibration on the bone-cement interface was studied using microfocal radiography (MFR) and scanning electron microscopy (SEM). Effects were studied in-vitro and in-vivo. In-vitro, samples of Palacos low viscosity PMMA were placed on blocks of Kiel bone and vibrated. MFR and SEM demonstrated an improvement in the appearance of the bone-cement interface. In-vivo, PMMA was injected into the upper tibia of the dog. An assessment of the effect of high and low pressure injection, and the effect of …


Ultrastructural Assessment Of Lesion Development In The Collared Rabbit Carotid Artery Model, J. E. Beesley, A. C. Honey, J. F. Martin Jan 1992

Ultrastructural Assessment Of Lesion Development In The Collared Rabbit Carotid Artery Model, J. E. Beesley, A. C. Honey, J. F. Martin

Cells and Materials

Cellular reactions associated with the formation of lesions generated in the carotid artery of rabbits fed either normal or high cholesterol diets by the placement of a flexible, silastic collar around the artery, were studied by electron microscopy.

Endothelial cells remained as a monolayer throughout lesion development. The endothelial cell surface in both experimental and sham operated carotids, 4 hours and 8 hours after the initiation of the experiments, were covered with platelets and leukocytes. Neutrophils were present until 7 days in the arteries from within the collar of animals maintained on a normal diet, but only to 1 day …


Summary Of Workshop To Review An Omb Report On Regulatory Risk Assessment And Management, John S. Evans, John D. Graham, George M. Gray, Adrienne Hollis Jan 1992

Summary Of Workshop To Review An Omb Report On Regulatory Risk Assessment And Management, John S. Evans, John D. Graham, George M. Gray, Adrienne Hollis

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

Summary of the results of an invitational workshop conducted to peer review the 1990 OMB report, CURRENT REGULATORY ISSUES IN Risk ASSESSMENT AND Risk MANAGENMENTIN REGULATORY PROGRAM OF THE UNITED STATES GOVERNMENT, APRIL 1, 1990 - MARCH 31, 1991.


Translation Of 'Kamalakanta: A Collection Of Satirical Essays And Reflections', Monish Ranjan Chatterjee Jan 1992

Translation Of 'Kamalakanta: A Collection Of Satirical Essays And Reflections', Monish Ranjan Chatterjee

Electrical and Computer Engineering Faculty Publications

This venture was born initially out of the desire to make those works of Bengali literature which have moved me profoundly, and which I consider first-rate by any yardstick, available to friends and fellow enthusiasts who cannot read the original. In attempting to channel literary and philosophical masterpieces into a different medium, I Have experienced firsthand the formidable challenge that a translator must face because not only of the barrier imposed by the languages involved, but perhaps more so because .of his or her own severely inadequate faculty being called upon to match both the genius and the inspiration of …


Towards The Use Of Situational Information In Information Retrieval, Robert N. Oddy, Elizabeth D. Liddy, Ann Bishop, Eileen Martin, Joseph Elewononi, Bhaskaran Balakrishnan Jan 1992

Towards The Use Of Situational Information In Information Retrieval, Robert N. Oddy, Elizabeth D. Liddy, Ann Bishop, Eileen Martin, Joseph Elewononi, Bhaskaran Balakrishnan

School of Information Studies - Faculty Scholarship

This paper is an exploratory study of one approach to incorporating situational information into information retrieval systems, drawing on principles and methods of discourse linguistics. A tenet of discourse linguistics is that texts of a specific type possess a structure above the syntactic level, which follows conventions known to the people using such texts to communicate. In some cases, such as literature describing work done, the structure is closely related to situations, and may therefore be a useful representational vehicle for the present purpose. Abstracts of empirical research papers exhibit a well-defined discourse- level structure, which is revealed by lexical …


Dynamic Fish Growth Modeling For Tailwater Fishery Management, Ming Shiao, Gary Hauser, Gary Chapman, Bruce Yeager, Tom Mcdonough, Jim Ruane Jan 1992

Dynamic Fish Growth Modeling For Tailwater Fishery Management, Ming Shiao, Gary Hauser, Gary Chapman, Bruce Yeager, Tom Mcdonough, Jim Ruane

United States Department of Energy: Publications

Tailwater fisheries below hydroprojects are affected by variable flows and water quality in dam releases. The Tennessee Valley Authority (TVA) identified undesirable flow regimes, low dissolved oxygen (DO) concentrations, and undesirable temperatures as having the greatest biological impact on tailwater, and steps are being taken to mitigate impacts at numerous dams. To help evaluate mitigation efforts, an interdisciplinary team of water quality modelers, fisheries biologists, and environmental engineers developed a one-dimensional dynamic fish growth model. This model was coupled with previously developed dynamic flow and water quality models. The model results were compared to (1) fish growth data in Norris …


A Model For A Model: Pressure Jackets On Nude Mice With Implants Of Hypertrophic Scars, C. Ward Kischer, Jana Pindur Jan 1992

A Model For A Model: Pressure Jackets On Nude Mice With Implants Of Hypertrophic Scars, C. Ward Kischer, Jana Pindur

Cells and Materials

The hypertrophic scar, a consequence of deep surface injury, is peculiar to humankind. Subcutaneous implants of these tissues in nude mice provide a quasi - animal model for experimental use. An efficacious treatment to promote acceleration of maturation of the hypertrophic scar is controlled topical pressure produced by flexible dacron fabric wraps. Implants in the nude mouse provide a model for study of the effects of pressure. Preliminary results indicate that those implants in nude mice, responding favorably to pressure jackets, show changes consistent with those previously obtained in human studies. The collagen matrix shows reduced density and parallel layering …