Digital Commons Network^™

A Color Petri Net Simulation Tool, Sanjaykumar V. Desai

Theses

A user friendly, modular and highly interactive graphical tool for drawing, editing and simulating color Petri nets is developed. The tool is designed to model concurrent and interlocked systems, such as flexible manufacturing systems, communication protocols and computer systems. A Color Petri Net(CPN) has a more concise graphical system representation than a standard Petri net, because net entities in CPN carry information. The CPNS(Color Petri Net Simulation) tool simulates a net having conflicts, reveals deadlocks, and creates a log file with the state history of the system yielding performance measures.

A Case Study On Petri Net Modeling, Animation, And Simulation, Suresh C. Gurala

Theses

Petri nets as a graphical tool has developed over the last decade into a suitable model for representing, modeling, designing, analyzing and studying concurrent systems. In this thesis, Petri nets are applied for analyzing, modeling and simulation of a flexible assembly station. An existing AT&T FWS200 flexible assembly workstation for printed circuit board is modeled using Petri nets without the consideration of insertion failures and other abnormalities in the system. The Petri net model is then simulated using Graphics simulation language (GSL).

Advanced Manufacturing Applications Of Cost Estimating Techniques For Metal Cutting Industries, Zubair Hamid

Theses

In this work, different cost estimating techniques in metal cutting industry were studied. A basic understanding of estimation concepts were given. The typical breakdown of total cost was also given and discussed in details. Practical applications of cost estimating is studied. The effect of different parameters which relate to the lot sizes or quantity were discussed. All these results show that total cost is minimum at a point which is called least cost point, after that cost increases because of the addition of extra resources, in terms of man, machine and increase in administrative expenses.

Bridge Deterioration Models, Christopher R.H. Howard

Theses

The deteriorated condition of America's bridges raises the need for a proper and optimal method of bridge management, from the conceptual stage through the construction stage, and throughout the useful life of our bridges. State agencies need to expand their data collection process so as to include additional information pertinent to the formulation of a credible system. This is critical in order to accommodate increased research efforts to investigate the behavioral pattern/s of the nations bridges and to eventually optimize bridge management systems. This thesis looks at the bridge deterioration model as a vital tool in realizing more effective bridge …

Implementing Computer Numerical Control Machine Tools In A Job Shop Environment, Rajesh Shah

Theses

Computer Numerical Control is one important phase to overall application of computer on the shopfloor. Today a large variety of CNC machine tools are offered by manufacturer following different standards. This thesis is organized with the purpose of comparing various technical and economical considerations for CNC machine tool purchase and application. The main purpose of study is to mention various features of CNC machine tools and its possible integration which can reduce product lead time and improve quality. General replacement minimum cost model is discussed with case study for economic justification of machine purchase. While discussing technical features emphasis is …

A Graphic Editor And Real Time Simulator Of Petri Net, Tenian Tang

Theses

A structurally designed graphic editor and real time simulator of Petri nets (PN) is presented. The package is programmed by Turbo C language, which runs in IBM-PC environmental with graphics adaptor. Various kinds of PN systems such as ordinary, general and timed Petri net can be modeled and analyzed by firing the models with real time token movement animations. Some properties of analyzed PN such as reachability, deadlock, firing time can be studied. Several illustrative examples are presented. The possible further enhancements are also discussed.

A Study Of The Potential Funding Mechanism For Surface Transportation In The New York Metropolitan Region, Krishnaveni Venkataswami

Theses

The present network of highways, soaring bridges, airports, seaports, and transit systems that serve the New York Metropolitan region are part of this region's inheritance from the generation of Americans who built them before us. These massive and sometimes daring achievements supported the economic growth of the region. Now that inheritance is in danger. The quality of the region's transportation infrastructure is barely adequate to fulfill current requirements, and insufficient to meet the demands of future economic growth and development. We are spending our inheritance.

A major problem is financial. Overall investment in transportation has slowed down in the last …

Image Deblurring For Visualization Of Coronary Microcirculation, Kaijun Wang

Theses

Blurred images of the rat coronary microcirculation have been obtained and processed. Heart motion, blood flow and noise cause the blur of the images. The objective of this thesis work was to study the effects of these factors on image quality and assess several models for image deblurring. The Wiener Filter and the Powei Spectrum Equalization Filter were implemented and were added to the existing image processing software. The images obtained after the application of these filters showed significant improvement over the original blurred images.

Error Detection And Correction In Compressed Data, Nadir Sezgin

Theses

Encoded data is very sensitive to the channel errors. Especially if the data is compressed by Arithmetic Encoding procedure, then the error propagation is very high. The error propagation in Arithmetic Coding is studied. Exploiting the high error propagation property when compressing data by Arithmetic encoding procedure, two different algorithms have been proposed for error detection and correction. Under certain conditions these algorithms detect and with a very high probability correct the errors introduced to the compressed data.

Design And Development Of An Automated Assembly System In A Discrete Manufacturing Environment, Sandeep K. Desai

Theses

This work is dedicated to extend the technology of automated assembly to include small and thin parts, light in weight. As the parts are thin a problem exists in the feeding process and orientation. The objective of project is to overcome this difficulty. The main theme of this thesis is to reduce labor cost and to improve productivity and quality of assembly operations by introducing low cost automation in the companies having discrete manufacturing environment.

An example of assembly involving a thin part has been selected. Two components from an electrical switch assembly are chosen, namely the spring and rivet. …

Biodegradation Of Tnt (2,4,6-Trinitrotoluene), Jin Lou

Theses

This study summaries the results of various methods treating 2,4,6-trinitrotoluene (TNT). Review of available literatures revealed that the most commonly used techniques in full-scale plant for TNT removal are chemical oxidation and carbon adsorption.

From economic point of view, the biological treatment system will be much more cost-effective. Various methods for improving the efficiency of biological system treating TNT wastewater were developed in the laboratory. Current laboratory results show that by isolating appropriate microorganisms under adequate conditions, TNT wastes can be degraded successfully.

At the some time, some pretreatment technologies are recommended in this study for improving the performance of …

An Implementation Of Bionomial-Qmf For Subband Coding Of Speech, Feng Chen

Theses

A real-time subband speech codec is implemented by the author on TMS320C25 digital signal processor based hardware for speech compression down to 0.25 bit per sample.

The Binomial Quadrature Mirror Filters (B-QMFs) are employed as the basic block for the hierarchical, dynamic tree, analysis/synthesis filter bank. After the analysis, available bits are optimally allocated among subbands. Band statistics are updated to overcome the nonstationarities of speech signal.

The energy compaction performance of this codec is compared with different subband and DCT in simulations for speech signals and AR(1) source models.

It is shown that the speech codec implemented provides an …

Computer-Aided Process Planning (Capp) Sorich, Sohail Pirzada

Theses

The last two decades have witnessed the increasing role of the computer in the process planning function. This has been further enhanced by the advent of the knowledge based expert system, and its impact on Computer Aided Process Planning (CAPP). CAPP has emerged as a strategic link between design and manufacture. This thesis discusses the various methods used in the process planning function. Group Technology (GT) plays a pivotal role in establishing CAPP. The utilization of Artificial Intelligence techniques in CAPP is listed. This study also presents an Interactive Software adaptive to product/part configuration variables.

Software Development For Analysis Of Stochastic Petri Nets Using Transfer Functions, Aman U. Jamwal

Theses

This thesis research is an implementation of a closed-form analytical technique for study, evaluation and analysis of Stochastic Petri Nets (SPN). The technique is based on a theorem that an isomorphism exists between an SPN and a Markov Chain. The procedure comprises five main steps: reachability graph generation of the underlying Petri net, transformation of the reachability graph to a state machine Petri net, calculation of transfer functions, computation of equivalent transfer functions via Mason's rule, and computation of performance parameters of the SPN model from the equivalent transfer functions and their derivatives. The software is developed in UNIX using …

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 …

Influence Of Heavy Metal Concentration On Rotating Biological Contrator Performance, Huei-Sheng Cheng

Theses

Seven heavy metals ( Fe⁺², Mn⁺², Zn⁺², Ag⁺, Pb⁺², Cu⁺², Cd⁺² ) at various concentrations were investigated in a Rotating Biological Contactor (RBC) system. The experimental data indicated that the degree of heavy metal toxicity in the biological system mainly depended on the ratio of inflow heavy metal concentration to organic loading. The optimal ratio of heavy metal to organic loading was determined on the basis of the maximum removal of chemical oxygen demand (COD) under different operating conditions. In addition, the effect of heavy metal on …

Response Characteristics Of Inelastic Single Degree Of Freedom Systems Subjected To Intraplate Earthquakes, Linda C. Jones

Theses

Within recorded, although not recent, history, there have been several large magnitude earthquakes in the Eastern and Central United States and the need to provide measures to protect from potential damage is recognized by the engineering community. Since there are inherent differences between earthquakes that occur along tectonic plate boundaries, interplate, and those that occur within the plate boundaries, intraplate, it is important to understand how these differences impact structural design. A parametric study of single degree of freedom systems subjected to various recorded and artificial ground motions was performed to identify the variations in response characteristics.

It was found …

Stability And Durability Of Large Aggregate Asphalt Concrete, Rais A. Khan

Theses

There are many factors which affect the properties of asphalt concrete and one of these is a maximum aggregate size used in the mix. In this study of the effect of maximum aggregate size on Marshall stability, flow and durability of asphalt aggregate mixtures is investigated.

Two different mixes having gradations with maximum aggregate sizes of 3/4 and 1-1/2 inches were considered. The optimum asphalt content for mix having 3/4 inch maximum aggregate size, was determined by the standard Marshall procedure. The optimum asphalt content for the mix having 1-1/2 inch maximum aggregate size, was estimated based on thickness of …

Vision-Guided Servoing Robot Arm System, Shing Lee

Theses

This thesis investigate the problem of tracking 2-D circle parts with an eye-in-hand robot arm system. A vision module capable of measuring the motion of a circle is developed. Two algorithms based on the conic equation representation of circle and the symmetric property are developed. The first algorithm approximates the image of the circle as an ellipse. The second algorithm use the arc radius estimator to extract two image points of the circle located at the center of the largest arc. These image points are then used to solve for the inverse perspective transformation. An inverse kinematics solution based on …

Development Of Cellular Manufacturing Systems For Overall Production Efficiency, Srinivas Lokula

Theses

For years the industrial job shop is facing an increase in complexity and decline in productivity due to increase in parts mix, volume of parts, plant size, machine production rates and part complexity. The development of Group Technology and Cellular Manufacturing seeks to eliminate or minimize complexity and to maximize productivity.

Cellular manufacturing is the physical division of job shop's manufacturing machinery into production cells. Each cell is designed to produce parts requiring similar machinery and machine operations. Cellular manufacturing is one of the best manufacturing techniques to support Just In Time manufacturing and Total Quality Management.

This thesis work …

Design For Manufacturability (Computer Aided Optimum Gear Design), Narayan R. Mareddy

Theses

Design for manufacturing has design as the first manufacturing step. It is important to recognize the importance of design clubing with manufacturing to reduce the production, set up time. In this thesis concepts of design, manufacturing and four different ways of bringing design and manufacturing together are discussed in detail.

As there are large number of variables in the gear rating equations, it is very difficult to achieve optimum design by manual methods unless an extensive trial and error process is carried out. An algorithm has been developed which allows rapid convergence to the optimum gear design. The algorithm has …

Computer Aided Design Of A Broadband Microwave Power Divider, Jaideep Mukherjee

Theses

The purpose of this thesis to provide alternative design procedure for a power divider that has broadband characteristics. The Wilkinson power divider consisting of cascaded quarter wave sections is known to increase the bandwidth while maintaining high isolation and good match conditions at individual ports. Resistors placed between the quarter wave sections served to increase isolation. The values of required components were determined using odd and even mode analysis. In this work, the approximate theory developed previously is used as a preliminary design model, and it is extended further by considering optimization techniques and coupling between adjacent arms. This novel …

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 …

The Strength Of Cement Bentonite In Containment Structures, Liong Tin So

Theses

In recent years the use of cutoff or slurry walls has increased in the containment of hazardous waste. Several materials have been utilized for backfill in slurry walls. Two important properties of the material are shear strength and permeability. Previously, sodium bentonite had been used. However, it was discovered that variable pH would cause an increase in permeability. Studies have shown calcium bentonite have a constant permeability with varied pH (Oweis and Khera, 1990). This study was undertaken to determine strength of calcium bentonite as affected by cement and slag.

Triaxial shear tests and unconfined compression tests were done on …

Automated Eeg Analysis And Spike Detection, Walter Vanderschraaf

Theses

EEG analysis of epileptic patients is extremely time consuming. Patients are monitored up to 36 hours at a time. The neurologist must visually review stacks of EEG records to determine whether they contain epileptic or artifactual activity. This process is very subjective and can vary from one neurologist to another based on his or her training and experience. The neurologist is only human and may tire or lose his or her concentration. Automated EEG analysis can efficiently reduce the amount of data and time involved in analysis. It is also more consistent and objective than human analysis.

The main objective …

Conditional Artificial Dielectrics ; Fabry-Perot Etalon, Ling-Yi Hu

Theses

Fabry-Perot etalons are optical resonators comprise of two mirrors and a spacer layer. By embedding a thin, photo-sensitive layer ( Conditional Artificial Dielectric - CAD layer ) in the middle of the spacer layer, we were able to photo-control the transmission properties of a Fabry-Perot etalon. Different structures have been analyzed and measured to find that a change of .01 was photo-activated in the refractive index of the Conditional Artificial Dielectric layer.

Simulation And Modeling Of Kinetics Of Silicon Oxidation In The Thin Oxide Regime, Tirthankar Dutta

Theses

Thermal oxidation of Silicon in dry O₂, in the thin regime(< 500A) is of vital importance to VLSI device engineers, because thin layers of SiO₂ are exclusively used as gate dielectric for high performance of MOS devices. There exist a number of models to explain the kinetics of oxidation in this thin regime. However there is considerable variance among them and the reported rate constants, which are supposed to describe the oxidation process. Rather than arriving at an alternative model, the present study aims at an extensive study and simulation of existing models of oxidation in dry oxygen, in the thin regime, with a recent set of experimental data and …

Strength And Fragility Of Concrete, Kang-Qun Shao

Theses

It is known that both strength and fragility are two of the most important properties in concrete. In this research, theories of Chemistry, Physical Chemistry of Surfaces, Thermodynamics and Fracture Mechanics are used to study the relationships between the macromechanical behavior of concrete and the microstructure in concrete. The objectives of this research are therefore to find some effective ways to explain theoretically why the concrete is so brittle (fragile) and how to increase its strength or to decrease its fragility. Based on the present studies, an equation is formulated to calculate the coefficient of the fragility (or brittleness) of …

Analytical Methodology For Atm Control Panel Design, Donald C. Johnson

Theses

This thesis presents a methodology for control panel design and layout along with a case study of an automated teller machine (ATM). A predictive model of human endurance and fatigue is developed from anthropometric, biomechanical and kinematics research. The layout problem is formulated to assign controls to locations to minimize the fatigue imposed on an operator performing a known set of tasks. A family of optimal and near-optimal layouts are found using conventional algorithms. The final hardware design refinements are suggested by human factors concerns. Ergonomic guidelines are also proposed for software aspects of the design. The methods and guidelines …

Frictional Resistance Of Geotextiles, Md. Khairul Alam

Theses

The pullout resistance of geotextiles was examined using pullout tests. A suitable wooden box with large (2 ft x 2 ft x 4 ft) dimensions was used to avoid the effect of boundary and to simulate field conditions. Two types of failure patterns were observed. For shallow embedment (<3 ft), geotextile produced a movement of the surrounding mass of sand in the shape of an inverted cone due to interlocking friction between geotextile and sand particles. The cone angle decreases with increase in depth of embedment. For embedment equal to or greater than 3 ft., no sand cone developed and the failure occurred along the interface of geotextile and sand. For 1 ft. surcharge, the increase in the pullout resistance due to combined horizontal and vertical embedment was about 30 %.