Engineering Commons^™

An Examination Of Wing Rock For The F-15, Michael T. Davison

Theses and Dissertations

Wing rock in the F-15 was examined both analytically and experimentally. Using a previously developed model for the F-15, bifurcation analysis and continuation techniques were used to map out the periodic wing rock solutions and the equilibrium solutions leading up to wing rock. this was done for four maneuvers; a 1 g stall, rudder sweeps, constant bank turns and a symmetric pullup. To supplement this research, time history simulations were used to examine. the time history of wing rock. A study of stability derivatives was also done, to determine the critical parameters in wing rock. Bifurcation was also used to …

Determining The Chemical Composition Of Cloud Condensation Nuclei, Allen L. Williams, Jane E. Rothert, Kent E. Mcclure, Darryl J. Alofs, Donald E. Hagen, Daniel R. White, A. R. Hopkins, Max B. Trueblood

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This second progress report describes the status of the project one and one-half years after the start. The goal of the project is to develop the instrumentation to collect cloud condensation nuclei (CCN) in sufficient amounts to determine their chemical composition, and to survey the CCN composition in different climates through a series of field measurements. Our approach to CCN collection is to first form droplets on the nuclei under simulated cloud humidity conditions, which is the only known method of identifying CCN from the background aerosol. Under cloud chamber conditions, the droplets formed become larger than the surrounding aerosol, …

Manual Of Traffic Impact Studies : Draft, Soumya Sekhar Dey, Jon D. Fricker

JTRP Technical Reports

With intensification urban development and dwindling public resources, assessing the impacts of a new development (traffic impact analysis) is becoming an important planning tool for transportation engineers, so that the traffic impacts of new developments can be foreseen and effective mitigating measures can be planned using optimal allocation of the available funds. The study establishes a detailed and standardized methodology for traffic impact analysis. Although the procedure was developed for the Indiana Department of Transportation, it can be used by other transportation agencies as well with little or no modification.

A new methodology for estimating the percentage of pass-by trips …

Recycled Materials In Kentucky Highway Construction, David Q. Hunsucker, Laura Whayne

Kentucky Transportation Center Research Report

The objectives of this study were to identify and list waste materials which should be recycled to reduce solid waste disposal; report current and past efforts of the Kentucky Department of Highways to utilize recycled and waste materials; determine through a thorough literature search and review, the efforts of other local, state, national and international transportation agencies to utilize recycled materials; and, present preliminary recommendations listing areas where additional recycling efforts appear promising, feasible and needed.

Waste materials that were identified which could be recycled to reduce solid waste disposal included demolition waste (building rubble, recycled concrete pavement, recycled asphalt …

Analysis Of Algorithms For Velocity Estimation From Discrete Position Versus Time Data, Ronald H. Brown, Susan C. Schneider Phd, Michael G. Mulligan

Electrical and Computer Engineering Faculty Research and Publications

Algorithms for constructing velocity approximations from discrete position versus time data are investigated. The study is limited to algorithms suitable to provide velocity information in discrete-time feedback control systems such as microprocessor-based systems with a discrete position encoder. Velocity estimators based on lines per period, reciprocal-time, Taylor series expansion, backward difference expansions, and least-square curve fits are presented. Based on computer simulations, comparisons of relative accuracies of the different algorithms are made. The least-squares velocity estimators filtered the effect of imperfect measurements best, whereas the Taylor series expansions and backward difference equation estimators respond better to velocity transients.

Improving The Throughput Of Plasticating Extruders : Manufacture Of Non-Circular Pellets, Measurement Of Their Interparticulate Friction Coefficient, And Implications For Screw Design, Chia-Ying Liu

Dissertations

This dissertation addresses the hypothesis that the interparticulate friction coefficient of a bed of polymeric particulates is a function of the cross-section of the pellets. Most pellets have a circular cross-section especially those that are strand cut. But when such pellets constitute a particulate bed there are few restrictions to adjacent pellets turning with respect to each other, or of the beds rupturing under shear load. This rupture can occur in plasticating extrusion, and it results in a poorly mixed melt with an inhomogeneous temperature distribution. The temperature fluctuations cause viscosity fluctuations which in turn cause pressure fluctuations. The pressure …

Computer Aided Shape Optimization Using Finite Element Analysis, Charanpreet Singh Bagga

Theses

Various theories behind Computer Aided Shape Optimization are studied. A special attention is paid to the shape representation, mesh generation and refinement during the shape optimization process. Shape optimization process for a wall bracket is performed using the Computer Aided Engineering package of I-DEAS. Finite element analysis of the wall bracket is done and the stress distribution over the bracket is studied. The bracket is trimmed in the selected low stress regions using shape optimization capability of I-DEAS and an optimized shape of the wall bracket is obtained. The end product is evaluated using Supertab module of I-DEAS as well …

Efficient Hypercube Communications, Shreyas R. Bhatt

Theses

Hypercube algorithms may be developed for a variety of communication-intensive tasks such as sending a message from one node to another, broadcasting a message from one node to all others, broadcasting a message from each node to all others, all-to-all personalized communication, one-to-all personalized communication, and exchanging messages between nodes via fixed permutations. All these communication patterns are special cases of many-to-many personalized communication. The problem of many-to-many personalized communication is investigated here.

Two routing algorithms for many-to-many personalized communication are presented here. The algorithms proposed yield very high performance with respect to the number of time steps and packet …

Mathematic Models On Leaching Behavior Of Chemical Solidification And Stabilization Process For Heavy Metal Sludges, Sz-Hung Chen

Theses

Chemical Solidification and Stabilization of toxic metal-containing sludges is one of the most important problems for environmental protection. Although Chemical Solidification and Stabilization of hazardous wastes prior to disposal is increasing in importance, very little work has been done concerning the leaching mechanisms and kinetic models.

In this study, we apply Freundlich & Langmuir isotherms on Chemical Solidification and Stabilization process, and the theoretical results match with experimental data very well. In the same time, we develop a simple methematical kinetic model which relates leaching concentration of heavy metal to curing time. In this study kinetic model, what you need …

A Finite Element Thermal And Diffusion Analysis At Bearing Metal Interface In Extrusion Processes, Biju Dennis

Theses

A mathematical model is developed to study the effect of extrusion speed and the bearing length on the surface temperature along the die billet interface. The surface temperature distribution resulting from the plastic work done on the die billet interface is studied. Finite element analysis is done on the model incorporating the mass transport effect occurring during the extrusion process and the interdependence of various parameters are presented. Die wearing problem is analyzed considering the effect of diffusion. Thermal analogy of the diffusion problem is utilized in the development of the mathematical model for diffusion problem and finite element analysis …

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 …

Ion Exchanged Glass Waveguides With Efficient Coupling To Fibers And Lasers, Shiqing Hu

Theses

To be of practical use in optical communications networks, optical components must have both low on-chip losses and efficient coupling to fibers, semiconductor lasers and detectors. In this thesis work two types of channel waveguides were designed and fabricated on BK7 glass substrate using a low-cost ion-exchange process. The first type of waveguide was formed in a simple sequence of ion-exchange and post-exchange annealing. These single mode waveguides had large mode size and were efficiently coupled to single mode fibers. The lowest loss achieved in fiber-guide direct coupling was 1.25 dB. The second type of waveguide was formed in a …

Conditional Artificial Dielectric : Optically Controlled Microwave Modulator, J. Manuel Jimenez

Theses

A conditional artificial dielectric with embeddings of either CdS, GaAs or Si in PMMA form the dielectric material of a microstrip in a homodyne microwave detection system. The system consists of a Michelson or Mach-Zehnder interferometers with the microstrip placed in one arm. The index of refraction of the microstrip substrate is modulated by chopped incident light causing amplitude and phase variations in the incoming RF signal. Those variations are detected by mixing the light modulated microwave carrier(information channel) with the unmodulated carrier (reference channel) in the interferometer. The output is sensed by the square law detector and a lock-in …

Series Compensation Investigation On The Hydro-Quebec And Nypa 765 Kv Transmission System : Modeling And Stability Analysis, Hans J. Candia

Theses

This thesis presents a mathematical approach for raising the power steady state stability limit by adding series capacitive compensation to a transmission line. The effect of series capacitive compensation and degree of compensation were investigated in detail. The power system studied includes an automatically controlled power system, IEEE Type I.

The results of the actual and theoretical steady state stability limits for a given series capacitance location and degree of compensation were obtained by applying the frequency domain technique. The natural frequencies of each compensated power network were examined.

The best location for series capacitive compensation is proposed which is …

Biodegradation Of Phenol And Benzoic Acid In Batch And Sequencing Batch Reactors, Stephane Reynaud

Theses

A pure culture of Pseudomonas aeruginosa ( ATCC 10145 ) was used for the biodegradation of phenol and benzoic acid. Two sets of small scale (shaker flask) experiments were originally performed: in the first set, phenol was the only carbon source present while in the second, benzoic acid was the sole carbon source. These experiments revealed the kinetics of benzoic acid degradation (they were found to be described by a Monod, non-inhibitory model), as well as of phenol biodegradation (they were found to be described by Andrews'inhibitory model) by Pseudomonas aeruginosa.

The kinetic expressions from the small scale experiments …

High Temperature Alloys Synthesis By Electro-Discharge Compaction, Kenji Okazaki

Chemical and Materials Engineering Faculty Patents

A method is provided for synthesizing high temperature alloys from elemental powders. The method includes the steps of placing the elemental powders to be processed in a die. A relatively high pressure is then applied to the powders. Substantially simultaneously, an electrical discharge is applied to the powders. The discharge is of relatively high voltage and current density to provide alloying. A product fabricated by the present method is also described and claimed.

Improved Crystalline Quality Of Si1-XGeX Formed By Low-Temperature Germanium Ion Implantation, Ken-Ichi Shoji, Akira Fukami, Takahiro Nagano, Takashi Tokuyama, Cary Y. Yang

Electrical and Computer Engineering

Improvement of crystalline quality in Si_1-xGe_x formed by germanium ion implantation has been found. End‐of‐range defects were drastically reduced in number by lowering the substrate temperature during implantation with doses on the order of 1016 cm−2. This improvement was confirmed by electrical characterization of p‐n junctions formed in the SiGe layer as well as by transmission electron microscopy.

An Investigation On The Skill Requirements Of A Manufacturing Engineer In A Computer Integrated Manufacturing Environment, Wayne E. Frost

Graduate Research Papers

The problem for this study centers on these questions:

What skills will a manufacturing company's manufacturing engineers require to : 1) Implement successfully computer integrated manufacturing. 2) How will they obtain these skills?

Developing Image Processing Tools In X Window System, Xin Zhang

Dissertations and Theses

The X Window System is an industry-standard software system which facilitates programmers to develop portable graphical user interfaces. This thesis describes an image processing tool developed under the X Window System. A multiwindow image display software with image editing and improvement functions is developed. The software has four modules: environment generation, image creation, image editing and image improvement.

The environment generation module creates working windows, scrollbars, dialogbox and pulldown menu buttons, and tracks mouse cursor positions. The working windows are three adjacent windows allowing display of three different images simultaneously. The dialogbox provides an interface between the user and the …

Computational Investigation Of Slot Blowing For Fuselage Forebody Flow Control, Scott M. Murman, Yehia M. Rizk, Russell M. Cummings, Lewis B. Schiff

Aerospace Engineering

This paper presents a computational investigation of a tangential slot blowing concept for generating lateral control forces on an aircraft fuselage forebody. The effects of varying both the jet width and jet exit velocity for a fixed location slot are analyzed. This work is aimed at aiding researchers designing future experimental and computational models of tangential slot blowing. The primary influence on the resulting side force of the forebody is seen to be the jet mass flow rate. This influence is insensitive to different combination of slot widths and jet velocities over the range of variables considered. Both an actuator …

Eies 2 : A Distributed Architecture For Supporting Group Work, Computerized Conferencing & Communications Center, James Whitescarver, Robert M. Czech, Sreenivas Reddy, Ajaz R. Rana, Murray Turoff

Computerized Conferencing and Communications Center Reports

The Computerized Conferencing Center (CCCC) at New Jersey Institute of Technology (NJIT) has been researching on-line group communications for 17 years by developing and studying tools to advance the "collective intelligence". The Electronic Information Exchange System 2 (EIES2) provides a research, development and operational environment for distributed computer supported cooperative work (CSCW) systems. The EIES 2 distributed Smalltalk processor provides for rapid prototyping and implementation of muti-media CSCW facilities in the network environment. The Smalltalk support of the object model, and meta-language properties make it ideally suited for incremental development CSCW applications. The EIES2 communication environment supports a decentralized network …

Acuta Enews January 1992, Vol. 21, No. 1

ACUTA Newsletters

In This Issue

Are you ready for the ADA?

Alabama regulators take aim at campus phone services

NATA asks that blocking services be mandatory for LECS

Distance education programs, technology continue to mature

Message From The President

Merging technologies may mean crossfire of competition

Monographs: opportunity to share knowledge

ADA to have far-reaching effect on telecommunications

Party Line

Annenberg announces distance learning grants

Marketplace Update

All Optical Synchronisation With Frequency Division Using A Self Pulsating Laser Diode, Gerald Farrell, P. Phelan, Joe Hegarty

Articles

A master optical clock from a mode locked laser is distributed to two slave twin section lasers. One slave laser divides the optical modulation frequency by 2, the other slave laser multiplies the frequency by 2. It is also possible to vary the multiplication4ivision ratio in a slave laser using only DC control of the absorber of the twin section laser.

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

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

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 …

The Effect Of Serial Passaging Of Lactobacilli In Liquid Medium On Their Physico-Chemical And Structural Surface Characteristics, Pieter L. Cuperus, Henny C. Van Der Mei, Gregor Reid, Andrew W. Bruce, Antoine E. Khoury, Paul G. Rouxhet, Henk J. Busscher

Cells and Materials

The aim of this study was to examine the effect of serial passaging in liquid medium on physico-chemical and structural surface characteristics of two lactobacillus strains. To this end, starting cultures (p = 1) of urogenital isolate L. acidophilus RC 14 and poultry isolate L. fermentum B54 were serially passaged in liquid medium up to 20 times (p = 20). In both strains, similar physico-chemical and structural changes were observed following serial passaging. According to water contact angle measurements , cells in p = 20 cultures became less hydrophobic. Microelectrophoresis showed that isoelectric points shifted towards the acidic region upon …

The Incorporation Of Glass-Ceramic Implants In Bone After Surface Conditioning Glow-Discharge Treatment, C. M. Muller-Mai, C. Voigt, R. E. Baier, U. M. Gross

Cells and Materials

Glow discharge (GD)-treated and autoclaved glass-ceramics of bone-bonding and non-bonding type were implanted into the femoral diaphysis of rats for 3, 7, 14 and 28 days and were investigated by applying light microscopy and histomorphometry , and scanning and transmission electron microscopy. More bone and chondroid, and faster osteoid development were observed at glow-discharge treated implants even in nonbonding implants when compared to autoclaved controls. Ultrastructural investigations showed a higher leach ing- rate of GD-treated bone-bonding implants during the early days after implantation leading to a higher rugosity, whereas no morphological changes were observed on non-bonding implant surfaces. More extracellular …

Architectural Support For Designing Fault-Tolerant Open Distributed Systems, Salim Hariri, Alok Choudhary, Behcet Sarikaya

Electrical Engineering and Computer Science - All Scholarship

A distributed system consists of autonomous computing modules that interact with each other using messages. Designing distributed systems is more difficult than designing centralized systems for several reasons. Physical separation and the use of heterogeneous computers complicate interprocessor communication, management of resources, synchronization of cooperating activities, and maintenance of consistency among multiple copies of information. The main advantages of distributed systems include increased fault-tolerance capabilities through the inherent redundancy of resources, improved performance by concurrently executing a single task on several computing modules, resource sharing, and the ability to adapt to a changing environment (extensibility). Distributed systems cover a wide …

Spring 1992, 90.9 Wmpg Fm

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