Engineering Commons^™

Linearization Accuracy In Probabilistic Load Flow, Guan-Zhong Liang

Theses

This paper presents a linear load flow method which can be used for probabilistic load flow analysis. The method is based on least-square estimation. To estimate its accuracy in linear load flow calculations, the method and a previously developed linear load flow method are applied to a typical power system and the results evaluated. Comparable accuracy is noted.

An Analysis Of Minimum Shift Keying From The Viewpoints Of Quadrature Multiplexed And Multi-H Continuous Phase Modulation Signaling, Alfred Anthony De Seta

Theses

Minimum Shift Keying (MSK) is a bandwidth efficient modulation scheme which offers superior performance over Quadrature Phase Shift Keying (QPSK) and Offset Quadrature Phase Shift Keying (OQPSK). This paper discusses these modulation techniques from a quadrature multiplexed signaling viewpoint and compares them in terms of error performance, bandwidth properties and bandlimiting and hardlimiting effects. MSK is also considered as a special case of a multi-h Continuous Phase Modulation (CPM) signal and the Viterbi algorithm is presented as an optimal detection scheme for this class of signals. A computer simulation is performed with the VA as the detection mechanism for an …

Reliability Study Of Liquid Crystal Display, Kalpesh Mahendra Desai

Theses

The purpose of this thesis is to study the reliability of liquid crystal display under different temperature conditions. To accomplish this, accelerated life testing was done on the soft glass and the hard glass liquid crystal display units at 77 C and 85 C temperature without any added humidity or voltage.

As the current is a usefu1 indicator for probable wear of liquid crystal display, leakage current was measured at 0 hour, 1000 hours, 2000 hours and 3000 hours when the units have stabilized at room temperature.

The date shows higher spread for the hard glass units. This may indicate …

A Computer Aided Manufacturing System For Small Quantity Prototype Board Production, Santiago Garcia-Perez

Theses

A matrix addressed manufacturing tool has been built, tested, and integrated in a system aimed to exploit wire-wrap wiring technology for protoboard production in small quantities. Extensive software exploits the power and economy of the personal computer as a superb manufacturing tool and documentation system. Computer graphics are used as a visual aid that takes advantage of the cognitive capabilities of the human mind and eliminates the boredom and high costs involved with heavy automation achieving instead a tolerable level of human engagement with significantly increased efficiency. The approach presented is new and delivers substantial gains in productivity. The software …

Microcomputer Local Area Network Interface, David W. Juan

Theses

A Microcomputer Local Area Network Interface system for use in the study of Local Area Network has been built and tested. The special feature of the system is data transmission/receiving and error detection/recovery. The system adapted the International Standards Organization (ISO) Open System Interconnection COSI) model. It used the star topology and implemented the physical layer, data link layer and network layer. The results of the system indicated the data communications and resources—sharing between microcomputers.

The Acquisition Of Direct Sequence Spread Spectrum Communication Systems, Anthony Donald Demeri

Theses

This Paper surveys different techniques of acquiring Direct Sequence Spread Spectrum Systems.

It classifies different systems, indicates the strongpoints and weakness of each, along with some applications.

One method, The Single Dwell Serial PN Acquisition System is then focused on in detail. The detail includes analysis of standard version, derivation of the mean time to acquire, the variance, the probability of detection and the probability of a false alarm.

In the last section of the paper the analytical results of the Single Dwell Serial PN Acquisition System shall be confirmed by computer simulation.

Computer-Aided Design Of A Waveguide To A Suspended Stripline Transition For Millimeter-Wave Applications, Hsin-Yen Peng

Theses

Realization of millimeter-wave systems on suspended striplines necessitates transitions from such lines into waveguides for measurements and other purposes. Transition can be obtained through coupling TE10 mode in the waveguide into a TEM mode in the suspended stripline. A continuous transition using tapered complementary unilateral finline and two gradually increasing conducting tapered ridges is studied here. The tapered region is modelled using a number of uniform sections with gradually changing cross sections. The junction separating the tapered section from the suspended stripline is modelled via physically and electrically continuous terminations. Physical continuity approach is more flexible for manufacturing purpose at …

Reliability Studies On Solid Tantalum Electrolytic Capacitors By Means Of Accelerated Life Tests, Venkata R. Golthi

Theses

The purpose of this thesis is to understand the failure mechanisms in Solid Tantalum Capacitors encapsulated in plastic, and to suggest the precautionary measures that prevent the occurrence of these failures.

The reliability of Solid Tantalum Capacitors encapsulated in plastic is of considerable interest because in some applications where the mechanical accelerations or shocks are considerable the "better" "hermitically" sealed type are not able to sustain themselves. Poor adherence between the dielectric film and the base metal Tantalum under the conditions of sudden mechanical shocks, causes problems.

Our study was carried out in two different directions, theoretical and experimental. The …

Dynamic Laryngeal Analysis : Hardware And Software, Augustine Chan

Theses

A data acquisition and analysis system has been built and tested for the study of laryngeal dynamics: The system uses a computer to control the digitizing rate and to coordinate the pitch prompting for the subject. Tokens of steady state laryngeal vibration are obtained from an electroglottograph when the subject intones a series of computer prompted pitches in a musically scalar sequence. The system digitize the data at a basic rate of 200 samples per laryngeal cycle: This procedure enables the system to perform a modal analysis of laryngeal function: The signal processing and analysis procedure developed displays voice registration …

The Interfacing Between The A/D Converter, Buffer Memory And Hx-40 Microcomputer, Yu-Hwa Chu

Theses

The data acquisition system which includes A/D converter, buffer memory, and address generator, is to digitize the signal for the computer use. The special feature of this system is the computer controlled digitizing rate over a range from 35K to 0.

The interfacing between Motorola 68000 E.C.B. to H.P. 64000 Development System is the simple example for data communication. How to make the protocal to be compatible is the main point. H.P. 64000 is treated as a host computer because it has the capability for data management and large memory for storing data.

Design Of Code Division Multiple Access Systems, Nakrendrakumar Patel

Theses

The intent of the work "Design of Code Division Multiple Access systems (CDMA) " is to consider different aspects of design with their effect on system performance. The generation of binary shift register sequences, that is maximal length sequences, with their properties are presented. From these maximal length sequences the Gold codes are obtained which are the most suitable approximately orthogonal codes for designing CDMA systems. These are discussed with their specific crosscorrelation properties. An extensive discussion is given of the difficult problem of synchronization, thatis bothacquisitionandtracking of pseudonoise sequences. Different synchronizing methods are discussed along with their relative performance. …

Digital Signal Processing On Tms32010 Evaluation Module And Analog Interface Board, Jiming Sun

Theses

The TMS32010 Evaluation Module (EVM) and Analog Interface Board (AIB) have been used to implement a digital signal processing system. This new system will be the hardware basis for research and development in the DSP field at NJIT in the future. This thesis will serve as a user's guide and overall technical manual for the system.

TMS32010 Assembler, Linker and Simulator in VAX-11 are used to develop the system software, then we can down load the object codes to the EVM through the MODEM in order to test them. By using the A/D and D/A converter as input and output …

Optimization Of Reactive Ionized Cluster Beam (R-Icb) Technique For Deposition Of Gan Films, Veronica S. Kyriacou

Theses

The deposition of GaN film onto glass substrate, using the Reactive - Ionized Cluster Beam deposition technique was studied. The creation of clusters is dictated by various parameters such as the vacuum pressure inside and outside the crucible, the crucible temperature, and the nozzle diameter of the crucible. Optimization of these parameters was experimentally studied, and deposition of gallium films on glass substrates was tried as a first step.

The direct heating method was used at first to get the 1100¬1300°C crucible temperature which was required for the creation of gallium clusters. Although different tungsten wire diameters and different number …

The Gpib User's Manual For Hx-40, Ding-Tang Li

Theses

A completed RS-232 to GPIB interfacing system has been built for HX-40 to master the GPIB oriented machine through its serial port. GPIB commands and data can be transfered between HX-40 and the slave station, which is a HP 3582A spectrum analyzer in this project. The data acquisition from serial to GPIB is done by a well-made GPNET mode 10 interfacing board in a transmitting rate of 9600 baud rate. GPNET exchanges data and commands with HX-40 through a RS-232 port, and passes them to the slave station through a GPIB port which is coordinated by GPIB protocol. A software …

Design And Construction Of An Atomic Nitrogen Source For Ion Cluster Beam Deposition Of Thin Film Nitrides, Sahar Elgharib

Theses

The objective of this thesis research was to generate atomic nitrogen to react with Ga being deposited by an Ion Cluster Beam method to prepare GaN thin films. An experimental reactor was designed and constructed to generate atomic nitrogen by making use of a microwave induced discharge to dissociate molecular nitrogen into atomic nitrogen. The concentration and the flow rate of the atomic nitrogen arriving at the substrate were measured by titration with nitrous oxide. The experiments were done with 0.32 square cm quartz tubing at room temperature over the nitrogen pressure range from 0.14 torr to 0.56 torr. Results …

Sputtered Mercury Cadmium Telluride Heterojunction Devices : Electrical Characteristics And Fabrication Process, Ashish N. Mistry

Theses

The main objective of this thesis was to grow high quality epitaxial films of the compound semiconductor Mercury-Cadmium-Telluride (MCT) on Silicon and MCT substrates,using sputtering technology. The research was aimed at investigating the heterojunction behaviour at such interfaces. Detailed studies about the heterojunction theory were made. Devices were made using MCT substrates prepared at the Santa Barbara Research Center (S.B.R. C.),California.

Experiments were designed to grow MCT films with high electron mobility and low carrier concentration in as-grown MCT films and some results were obtained close to reported data for high grade bulk material. Since the parameters involved in sputter …

Fast Discharges In Thin Liquid Layers, Charles J. Frei, Aidan O'Dwyer

Conference papers

Several mechanisms can be at work when electrical discharges occur across a thin layer of an insulating liquid. The evidence is derived from the time-lag distributions of series of consecutive discharges when the measurements are performed with a sequence of constant voltage pulses.

Total Refraction At Oblique Incidence By A Transparent Bilayer Coating On A High-Index Transparent Or Absorbing Substrate, R. M.A. Azzam, Karim Javily

Electrical Engineering Faculty Publications

Transparent bilayer coatings that produce total refraction (TR) of obliquely incident monochromatic light into an underlying substrate are considered. When the substrate is transparent, it is shown that TR takes place without any accompanying change of polarization. Totally refracting bilayers are realizable in the IR where high-refractive-index substrates are available. This is illustrated by a BaF₂–ZnSe bilayer on a Ge substrate at a 10.6-μm (CO₂-laser) wavelength and 45° angle of incidence. Limited changes of the angle of incidence, wavelength, and refractive indices and thicknesses of the two films of the bilayer are introduced, and their effects …

Investigation Of Electronic Holography Using Spice Computer Simulation Experiments, Monish Ranjan Chatterjee

Electrical and Computer Engineering Faculty Publications

Using SPICE experiments, it has been possible to verify most of the important aspects of electronic holography. The generation and properties of dynamic echoes under different types of nonlinearities have been extensively tested, and some new information has been garnered in the process. The case of pulse and generalized memory echoes has also been tested, and the results have been fairly satisfactory. Most of all, the simplicity with which the intriguing concept of memory echoes has translated into the circuit implementation on SPICE, and the closeness of the results to predicted behavior have been somewhat of a pleasant surprise.

Since …

An Investigation To Improve Linear Predictive Vocoder Pulse/Noise Excitation Models, Elizabeth Annella Martina Effer

Electrical & Computer Engineering Theses & Dissertations

The quality of synthetic speech from Linear Predictive (LP) vocoders is known to be degraded due to the lack of detail in the commonly used pulse/noise excitation model. In this investigation, it was hypothesized that this degradation is due to the lack of precise timing information in the pulses and to the constraint that each short-time segment of excitation be either an impulse train or white noise. Accordingly, more complex excitation models were implemented using precise timing from peaks in the residual and a mixture of pulses and noise. Since the LP residual is known to be the perfect excitation …

Further Development Of Preparation And Measurement Techniques For Triode-Sputtered Mercury Cadmium Telluride Thin Films, Tai-On Chan

Theses

The modified MRC 8800 R.F. triode sputtering system was used for mercury vapor sputtering (Hg^1-xCd^x)Te targets onto N-type (111) silicon substrates with a resistivity of 70 to 90 ohm-cm. Deposition rates were in the 2.6 to 3.6 A/sec range, A Hall mobility value, at 87°K, of 2550 Cm²/V•sec with a carrier concentration of 7(10¹⁵) cm^-3 was obtained for 9 μm thick films with an X-value of 0.25. Obtaining good sputtered films reliably was dependent on having targets that would not crack when bombarded with mercury ions. Improvements in the methods used …

Present Reliability Of Liquid Crystal Display Devices, C. N. Suresh

Theses

The purpose of this Thesis is to study the life of liquid crystal display devices as at present available in the market place. To accomplish this, accelerated tempera-ture conditions at 77°C and 85°C were used.

During the last few years, there has grown a tremendous interest in wide range temperature operating and fast LCDs. It is therefore important to understand how LCDs behave under these conditions.

The reliability of a liquid crystal display is usually measured in terms of a quantative degradation in electrical performance and a degradation in visual appearance. The degradation in visual appear6knce may manifest itself as …

Robot Manipulators And Control, Theresa Wu

Theses

This paper on Robot Manipulators brings together theories from three fields : computer graphics, kinematic equations and microprocessor based control.

There are four chapters in this paper, chapter one is the conceptual development on homogeneous transformations, express the position and orientation of the transposition of an object in Cartisian coordinates. Chapter two develops the method of obtaining the Cartisian coordinate position and orientation of the end effector for a manipulator, give the joint coordinate as input and use the homogeneous transformation to express the position and orientation. Chapter 3 is a very difficult one; it solves the parameters for the …

Identification Of Linear System With Feedback Input, Jyh Yang

Theses

A new procedure with feedback input is presented for identification of continuous-time systems. Using Lyapunov's direct method to prove it asymptotic stability. For the procedure to be applicable, it's assumed that all the state variables of the plant are accessible and that there is no measurement noise so the model reference scheme can be used to identify the parameters of the plant.

The procedure results in the convergence of every parameter of a model to the corresponding one of the system as the time approaching to infinite i.e. t→∞. Digital computer simulations are provided to demonstrate the feasibility of the …

Reliability Evaluation Of Liquid Crystal Displays Under Accelerated Test Conditions, Ravi Sankar Kalyandrug

Theses

This study has determined the effects of high temperature and humidity on the reliability of liquid crystal dis-plays.

Reliability life testing was done on variety of LCD samples under different operating conditions. All the besting was done under accelerated conditions, including high temperature of 85°C and relative humidity of 70%. A number of failure modes were identified in the long series'of tests.

Among many failure modes such as peeling of seal, degradation of polarizers etc., the most important is the degradation of alignment of liquid crystal molecules. Leakage current measurements were made on all the LCD samples before and after …

Frequency Characterization Of A Thin Linear Antenna Using Diakoptic Theory, Howard Harold Smith

Theses

A frequency dependent analytical expression for the input impedance of a thin wire antenna is obtained using diakoptic theory. In diakoptic theory the linear antenna is seperated into electrically short segments where each segment is treated as a two-port network. This approach eliminates the need for an integral equation formulation. An impedance matrix is found which characterizes coupling between all segments. By expanding the free space Green's function in a power series in wavenumber k each entry in the resultant impedance matrix is obtained as a function of frequency. Enforcement of the continuity of currents and equality of scalar potentials …

High Discharge Rate Characteristics Of Nickel-Cadmium Batteries For Pulse Load Filtering, Gregory M. Gearing, Michael B. Cimino, David H. Fritts, John F. Leonard, Anthony J. Terzuoli Jr.

Faculty Publications

Several tests of specially fabricated nickel-cadmium batteries having circular disk type electrodes were considered. These batteries were evaluated as filter elements between a constant current power supply and a five hertz pulsed load demanding approximately twice the power supply current during the load on portion of the cycle. Short tests lasting 10,000 cycles were conducted at up to a 21 C rate and an equivalent energy density of over 40 Joules per pound. In addition, two batteries were subjected to 10⁷ charge/discharge cycles, one at a 6.5 C rate and the other at a 13 C rate. Assuming an …

Investigation Of Pre-Detection Signal Processing Of Pseudonoise Communication Signals In The Presence Of Additive White Gaussian Noise And Cw And Bursty Interference, Israel Mayk

Dissertations

By comparison to conventional communication systems, spread-spectrum systems are known to be less affected by interference because of their large dimensionality in signal space. Nevertheless, significant performance degradation is experienced when large interference exists in a few or even one signal coordinates. In this case, interference reduction techniques are also known to provide additional processing gain. A novel class of pseudonoise (PN) invariant algorithms is derived to reduce the impact of interference and restore much of the structure of PN signals received in the presence of interference and noise. A PN signal received by a pre-detection signal process (PDSP) implementing …

An Electro Hydrodynamic Study Of The Negative Corona Electric Wind, Henry Thadei Kadete

Tanzania Journal of Engineering and Technology (TJET)

The velocity of corona generated electric wind is measured. From the velocity profile mass movement and electrokinetic conversion efficiencies are deduced. High speed schlieren photographs illustrate the form of the velocity distribution function as well as its high degree of turbulence.

Simple Graphic Routines Ease Drawing Of Artwork For The Fabrication Of Microstrip Lines, H Mgombelo

Tanzania Journal of Engineering and Technology (TJET)

A method which uses simple graphic routines available to general computer users for drawing diagrams intended to be reproduced on printed circuit boards (PCB's) is presented. Experimental verifications for the created microchip lines are reported.