Digital Commons Network^™

Minimum-Time Control For Submarine Interception, Zaiping Chen

Theses

This thesis attempts to offer a possible improvement for conventional anti-submarine system which is mounted on warship. It consists of two parts: the control law and its realization concerning the particular problem. The control based on optimal theory is devised for three-dimentional minimum-time interception. A microprocessor system is also designed to achieve all necessary steps to track and attack the target. The thesis focuses on the question of how to launch a group of subcharges to destroy a submarine cruising under water: find the optimal trajectory by developing a numerical method to solve the nonlinear dynamic system and design a …

A Graphical Tool For The Simulation Of Timed Petri Nets, Javaid Aslam Siddiqi

Theses

A highly interactive graphical tool is developed for the drawing and simulation of discrete event systems involving time constraints. The Timed Petri Net Simulator tool (TPNS) is capable of simulating systems with deterministic and stochastic delays. Performance and utilization parameters are collected during simulation for behavior and analysis purposes. Simulation results are stored in different files (log, verify, utilize, and mark). Conflict resolution on the basis of priority or random selection of multiple transitions in conflict is implemented to handle complex modeling situations. A user friendly interface is developed for effective interaction between the tool and the user. This interface …

Three Dimensional Visualisation Of Tmj Anatomy Using Mri Techniques, Mythreyi T. Krishnaswamy

Theses

The best assessment of temporomandibular joint (TMJ) can only be done by the scanning the jaw and getting an image without invivo analysis which causes patient discomfort. There have been innumerable efforts to get the best view using CT techniques for three dimensional visualisation. But very few have done work using MRI techniques.

The TMJ is an integral part of the jaw and helps in mastication and biting. Since the joint is a hinge sliding articulation any dislocation causes immense pain and discomfort.

To get a better assessment of the TMJ, MRI techniques have been used for data acquisition. The …

The Biological Basis Of Schizophrenia, Franz Sugarman

Theses

None provided.

Promotional Program For The Center For Graphic Design History, Kanchen Rajanna

Theses

None provided.

No Revelations, Mark C. Tierney

Theses

None provided.

Canmol : Expert System In Medicine, Kulin Hemani

Theses

The intriguing words for the nineteen nineties are "Expert Systems", and "Artificial Intelligence". To a layman these terms conjure up thoughts of spaceships and futuristic beings. In reality they exemplify man's capability to harness technology.

Expert systems are computer software programs that make use of previously accumulated knowledge to assist in solving complex problems.

In recent years the practice of medicine has changed dramatically from a fundamentally individually deductive approach to an Artificial Intelligence based science. The modern physician no longer draws conclusions simply by examining the patient. Today the physician employs sophisticated computer based diagnostic tools to generate a …

Development Of Technology For Glass Shaping By The Use Of Abrasive Water-Jet, Li-Yuan Shih

Theses

This study is to investigate the effects of AWJ properties on the results of glass machining and to develop a practical procedure for prediction of these results of abrasive waterjet (AWJ) machining. The use of glass in engineering and Abrasive Waterjet Cutting Technology are introduced. A practical technique to prevent defects and to improve the quality of the glass surface is suggested. A earlier parameter introduced, Exergy Distribution Density (EDD), is used in order to characterize the cutting conditions.

It was found that besides of EDD the results of machining are affected by the particles' destruction in the course of …

Delay Performance Of Cebus And Modified Cebus Schemes, Altaf Hussain

Theses

In this thesis the performance of the CEBUS (Consumer Electronics Bus), a local area network proposed by the Electronics Industries Association for the 'Smart House,' is analyzed under varying network load and traffic patterns that would occur in a typical home environment. Reduced complexity versions of the CEBUS scheme are compared with the standard CEBUS scheme.

It was found from simulation analysis that the delay in the CEBUS network, at a given network bandwidth, is dependent upon the message priority and the traffic pattern in the network. It was also observed that the performance of a modified CEBUS scheme was …

Cascading Space Efficient Variation Of The Lzw Algorithm And Arithmetic Coding, Shobha Raj

Theses

Two known compression algorithms appropriate for communication are LZW and the Arithmetic Coding method. Both are adaptive and require no extra communication from the encoder to the decoder. Here we have considered a space efficient variation of the LZW algorithm which achieves better compression.

We present a scheme to cascade the space efficient variation of the LZW algorithm with Arithmetic Coding into a space efficient data compression algorithm which achieves a higher compression ratio and is appropriate for communication.

Design And Simulation Of A Primitive Risc Architecture Using Vhdl, Evangelos Moustakas

Theses

Hardware Description Languages are used as the connecting links between the design of a digital system and the way this design is being represented in computers, with the ultimate goal being the simulation and verification of that design before the construction of any prototype. In this thesis, we follow all the steps of a RISC architecture design and finally use VHDL as the tool to describe, simulate and verify the design. By the unique abilities of VHDL we give both a structural and a behavioral description where the latter contains multiple description levels, from gate to Processor-Memory-Switch (PMS) . The …

Work-Preserving Real-Time Emulation Of Meshes On Butterfly Networks, Alf-Christian Achilles

Theses

The emulation of a guest network G on a host network H is work-preserving and real-time if the inefficiency, that is the ratio W_G/W_H of the amounts of work done in both networks, and the slowdown of the emulation are O(1).

In this thesis we show that an infinite number of meshes can be emulated on a butterfly in a work-preserving real-time manner, despite the fact that any emulation of an s x s-node mesh in a butterfly with load 1 has a dilation of Ω(logs).

The recursive embedding of a mesh in a butterfly presented by …

Nontraditional Machining Techniques With Emphasis On Waterjet Milling, Shiv K. Kunapuli

Theses

The rapid growth of harder and difficult-to-machine materials over the past two decades necessitates the development of compatible nonconventional machining techniques, as detailed in this work, with special emphasis on one of the most recent machining method, the abrasive-waterjet technique(AWJ).

The feasibility of using AWJ for milling on glass is investigated. Due to the large number of parameters involved in the AWJ technique, and the multitude of machining requirements, optimization of performance is the focus. These parameters include waterjet pressure, particle size, abrasive flow rate, traverse rate and number of passes.

Surface topography is found to be a function of …

A Biomechanical Analysis Of Three Humeral Fracture Fixation Systems, Alina Michelle Waite

Theses

Often, humeral fractures requiring internal fixation can be a challenging orthopaedic procedure. Each method of treatment possesses clinical and biomechanical advantages and disadvantages. Rigid plate fixation is highly successful in treating a large variety of long bone fractures. Nevertheless, excessive soft tissue dissection is necessary, and vascular and neural anatomy of the humerus can make plate application and removal difficult. An intramedullary nail offers a relatively simple procedure, thereby reducing these anatomical concerns. However, rotational instability at the fracture site is a common complication with a conventional intramedullary nail. Thus, a study was conducted to evaluate a new interlocking intramedullary …

Adaptive Filter Application In Fetal Electrocardiography, Xueqiang Zhou

Theses

A hybrid adaptive algorithm for cancelling the maternal electrocardiography (MECG) component in abdominal fetal electrocardiography(FECG) is described. This algo rithm combines the advantages of the orthogonal algorithm which was developed by Reichert(1977) and the multiple reference noise cancelling adaptive algorithm which was developed by Widrow(1975).

The simulating experiment was taken to test all of these three algorithms. It demonstrated that all these three algorithms can cancel the abdominal component of the maternal ECG with three limb lead ECG signals. and the hybrid algorithm is at least as effective as each other algorithm alone. In this experiment, the abdominal ECG signal …

Implementation Of An Integrated High Energy Beam Workcell, Varadaraj Souda

Theses

This study is an effort to advance the technology of machining by High energy beams. Investigation of the Waterjet, Plasma and the Oxyfuel beams was carried out to explore novel machining techniques. The study was focussed on three major objectives.

One of the major objectives was to set up an Integrated beam workcell consisting of the three beams. A hydroabrasive waterjet workcell was modified to install the three cutting tools to be along the same line of traverse. An integrated beam consisting of the thermal and the waterjet beams was produced because of this arrangement. The feasibility of using the …

Thermal Stresses In Closed Spherical Shells, Frank W. Keene

Theses

The purpose of this work is to discuss thermal stresses in closed spherical shells. This effort is further limited to linear thermoelastic stresses in "thin" shells. The basic concepts associated with three-dimensional continuum mechanics are presented in both direct and general tensor notation. The three-dimensional equations are reduced to the two-dimensional equations of shells under going finite displacements. These are subsequently reduced to those pertaining to spherical shells. A review of the recent literature associated with thermal stresses in spherical shells is included. An appendix is provided which reviews some of the basic elements of general tensors.

Within Normal Limits, Hikmet Safuoglu

Theses

None provided.

Image Coding Using Wavelet Transform And Adaptive Block Truncation Coding, Thanit Chaiyaboonthanit

Theses

This thesis presents a new image coding using wavelet transform and adaptive block truncation coding. Images are first pre-processed by the wavelet transform and then coded by the adaptive block truncation coding. Algorithms for both monochrome and color images are proposed and experimentally studied. The adaptive block truncation coding is also modified to achieve better performance. For coding monochrome images at the bit-rate region between 0.8 to 1.2 bits/pixel, the performance of the new coding is comparable to the ones of subband codings and other image codings using the wavelet transform; however, the new coding offers less computational load. The …

Marks: The Adorned Self, Tom Santelli

Theses

None provided.

Effect Of Dietary Lipids On Rat Alveolar Macrophage Function, Sangeeta R. Mehta

Theses

An in vitro assay has been developed to measure bacterial uptake by rat alveolar macrophages. The assay is used to study the effect of a diet rich in high omega-6 linoleic acid on the phagocytic response of the macrophages obtained from young and old rats. Within the range of diets studied, no significant difference (p<0.05) is observed in the phagocytic capability of macrophages from young rats. Significant difference is observed between diet groups for the old rats (p<0.05), with the group on a fat-rich diet showing suppressed phagocytic response. Significant difference is also found between age groups for the same diet (p<0.05), older animals showing suppressed response.

The Bandwidth Allocation Of Atm Control By Neural Networks, Jin-Syan Chou

Theses

In this thesis, we develop a neural network method based on Adaptive Resonance Theory to train and control the optimum bandwidth allocation of ATM network. In Broadband Integrated Service Digital Network (BISDN), the Asynchronous Transfer Mode (ATM) is already adopted as the transfer facility by CCITT. ATM is a high-bandwidth, low- delay, fast-packet switching and multiplexing technique. Using ATM technique, we can flexibly rearrange 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. Then, we use Adaptive …

Modification Of Wear Testing Methodology, Muhammed Farooq

Theses

In this work the existing computer controlled methodology has been modified A loading and unloading mechanism has been designed, manufactured and assembled. A specimen fixture has been designed and installed. Alloy steel specimens with different surface treatment were tested on the modified wear testing machine. Operational surface roughness was measured in all stages of running-in, steady state and catastrophic wear. The difference between technological and operational surface roughness was observed. The results show that the surface treatment by Plasma Ion-Nitriding with Magnetic treatment increases wear resistance. It was found that the coated material which had been magnetically treated with a …

Computer Graphic Simulation Of Sweeping Of Solid Objects, Jr-Jyun Jang

Theses

This thesis is on the computer graphic simulation of the swept volume of a solid object undergoing Euclidean motions (including translation and rotation). The study helps visualize different types of Euclidean motions and supports the previously developed swept volume theories by providing graphic realism.Included in the thesis presentation are the following :

1. Description of Euclidean motions of polyhedral objects, using ruled surfaces to represent swept volumes.
2. Representation of sweeping of solid objects, -using parametric cubic equation and sweep differential equation.
3. Simulation of motions of PUMA and IBM robots.
4. Wire-frame and shaded image displays of swept volumes.

Successor Employers' Obligations Under The National Labor Relations Act, Ting-Wang Lu

Theses

A wave of business acquisitions is currently sweeping the American corporate scene. Companies are purchasing both unionized and non-unionized businesses at a dizzying pace.

Not surprisingly, after years of confrontational contract renewals, management and 10 unions at the New York Daily News are jockeying for position in talks over agreements that expire on March 30, 1990. Throughout the long negotiation process then the strike began on October 25, 1990. End with Robert Maxwell, the British press baron, signing an agreement on his purchase of the Daily News on March 14, 1991. Obviously, this question of successor employers' obligations is one …

Influence Of Fly Ash Characteristics On Compressive Strength Of Mortar, Poorna Rajeswari Ratnaweera

Theses

Fly ash-cement mortar, constituting of fly ash, cement and sand, vary in strength characteristics from conventional cement sand mortar. Out of many parameters effecting the compressive strength characteristics of fly ash-cement mortar, four were investigated in this study. They are particle size and its distribution, weathering of fly ash, moisture content & water/cementitious ratio and mix proportioning.

Class F fly ashes from three different sources were used in this study. The particle size distribution and moisture content of fly ashes were investigated by standard ASTM methods. The unconfined compressive strength of mortar was obtained by testing 2"x2"x2" test cubes conforming …

Linear Regulator And Singular Control In Generalised State Space System, Devesh Kumar Thodimela

Theses

The problem of unconstrained optimal control of continuous-time singular systems is considered, by straight forward extension of some well-known equations derived for ordinary state-space systems by variational calculus and by the aid of the simplest algebraic and matrix tools: In this thesis, the interest is restricted to the case where the system is to be driven from a fixed initial state to a fixed final state as well as free final state tf while minimizing a performance index of the form

J = 1/2 ∫t_f t_o <( Y - Y_i), Q ( Y - Y_i) > d_t

Subject …

Development Of Plasma Ion Nitriding Process Parameters To Increase Durability Of Machine Components, Wenge Yang

Theses

In this work glow discharge ion nitriding process was selected to increase durability of machine components. To achieve this goal, the process parameters were designed, established and optimized based on the desired surface properties. The orthogonal experiment method is used to optimize multifactors process parameters. Using the image analyzing approach the microstructure of differently treated materials were obtained and analyzed. Developed coating layers, including different nitrides such as Fe3N, Fe4N, and diffusion zone were controlled by the optimized process parameters. Analysis of the obtained microstructure and microhardness showed the improvement of surface mechanical properties. Performed wear testing experiments showed increased …

Tisi2/N+/P Silicon Junction Formation By Ion Implantation Through Metal Technique, Ying Wu

Theses

Experimental analysis, modeling and simulation of the formation and electrical characterization of TiSi₂/n⁺/p-Si shallow junctions are presented here. The formation of shallow n⁺-p junction, by ion implantation of As⁺ through Ti films evaporated on p-Si substrates followed by Rapid Thermal Annealing ( RTA ) and conventional furnace annealing has been performed in these experiments. Structural techniques such as Secondary Ion Mass Spectroscopy ( SIMS ) and Rutherford Backscattering spectroscopy ( RBS ) experiments have been employed to characterize the devices, and RUMP simulator was used to analyze and interpret the RBS data. Current-voltage …

Petri Net Modeling And Analysis Of An Fms Cell, Paresh A. Patel

Theses

Petri nets have evolved into a powerful tool for the modeling, analysis and design of asynchronous, concurrent systems. This thesis presents the modeling and analysis of a flexible manufacturing system (FMS) cell using Petri nets. In order to improve the productivity of such systems, the building of mathematical models is a crucial step.

In this thesis, the theory and application of Petri nets are presented with emphasis on their application to the modeling and analysis of practical automated manufacturing systems. The theory of Petri nets includes their basic notation and properties. In order to illustrate how a Petri net with …