Engineering Commons^™

A Fuzzy Simulation Model Of Basic Commutating Electrical Machines, D. K. Chaturvedi, P. S. Satsangi, P. K. Kalra

D. K. Chaturvedi Dr.

Fuzzy Logic as applied to a great extent in controlling the process, plants and various complex systems, due to its inherent advantages like simplicity, ease in design, robustness and adaptivity. Aslo it is established that this approach works very well especially when the systems are not transparent. In this paper the approach is used for the modelling and simulation of an electrical machine to predict the behaviour of the machine under running conditionsas well as unde starting conditions. The starting characteristics of electrical machines are non-linear in nature, and it is very difficult to model them accurately. Also the developed …

Self-Enhancement Of Dynamic Gratings In Photogalvanic Crystals, Nickolai Kukhtarev, Sergei F. Lyuksyutov, Preben Buchhave, Tatiana Kukhtareva, K. Sayano, Partha P. Banerjee

Electrical and Computer Engineering Faculty Publications

We have developed a compact closed-form solution of the band transport model for high-contrast gratings in photogalvanic crystals. Our solution predicts the effect of the photoconductivity and the electric field grating enhancement due to the photogalvanic effect. We predict a pronounced dependence of the steady-state photogalvanic current on the contrast of the interference pattern and an increase of holographic storage time due to the enhancement of the photoconductivity grating contrast. In the high contrast limit and a large photogalvanic effect the refractive index grating will be shifted from the position of the intensity modulation pattern, contrary to the usually adopted …

Development Of The Industrial Expert System And Its Application For The Rational Choice Of Crushing And Grinding Facilities Of A Cement Factory (Développement Du Système Expert Industriel Et Son Application Pour Le Choix Rationnel Des Installations De Concassage Et De Broyage D'Une Cimenterie), Boukhemis Chetate , Cherif Kara, Galina Tcheremechko, Irina Merazka

Boukhemis Chetate

Les économies d’énergie électrique suscitent un intérêt croissant dans le domaine de l’industrie des matériaux de construction. En effet, la dépense en électricité peut représenter jusqu’à 50% de l’ensemble des coûts d’énergie nécessaires à la fabrication d’une tonne de ciment. Par ailleurs, environ 80% de l’énergie utilisée pour la fabrication d’une tonne de ciment est dépensée pour la fragmentation des matériaux de construction, c'est-à-dire pour le concassage et le broyage. Par conséquent, le choix rationnel des installations de concassage et de broyage et l’optimisation de leurs régimes de fonctionnement représentent un facteur important d’économies d’énergie. Toutefois, il est de plus …

Automatic Analysis Of Electronic Drawings Using Neural Network, Yi Shi

Dissertations

Neural network technique has been found to be a powerful tool in pattern recognition. It captures associations or discovers regularities with a set of patterns, where the types, number of variables or diversity of the data are very great, the relationships between variables are vaguely understood, or the relationships are difficult to describe adequately with conventional approaches.

In this dissertation, which is related to the research and the system design aiming at recognizing the digital gate symbols and characters in electronic drawings, we have proposed: (1) A modified Kohonen neural network with a shift-invariant capability in pattern recognition; (2) An …

Adaptive Bootstrap Signal Separators For Bpsk/Qam-Modulated Wireless Cdma Systems In A Multipath Environment, Nico J.M. Van Waes

Dissertations

CDMA is an attractive multiple-access scheme, because of its potential capacity increase and its anti-multipath fading capability. For satisfactory performance, however, the effect of the "near-far" problem has to be resolved. This problem can be combated by using power-control, which, however, results in an overall reduction in communication ranges, and thus in a loss of capacity. Among other methods for mitigating the near-far problem is the use of decorrelating receivers, both of fixed type, which directly utilizes the cross-correlation of the users codes, and of adaptive type, which uses recursive algorithms that leads to signal decorrelation. Not to lessen the …

Telephone-Accessed Controller Using Cebus For Device Control Over Power Line, Gerald Aska

Theses

The CEBus standard has made it possible for devices developed by different manufacturers to communicate over the power line. Further, the standard allows analog adjustments of devices besides transmitting and receiving binary information. This Controller extends the distance from which these devices can be controlled.

To extend the distance of communication with a device, a telephone line interface was developed that allows the user to communicate with a CEBus device via the Controller. The Controller responses [sic] to Central Office signaling and opens its communication channel to allow the user to provide it with the commands by using the telephone …

Experimental Investigations Of Wavelength And Angular Errors In Holographic Gratings With Non-Bragg-Matched Read Beams, Monish Ranjan Chatterjee, Vivek Ray

Electrical and Computer Engineering Faculty Publications

Perfect Bragg matching is generally desirable for accurate optical interconnections with holographic gratings. In reality, however, gratings may be illuminated by READ beams with non-Bragg-matched angles, or wavelengths, or both. In such cases, the scattered beams are generally misdirected, and may suffer loss of efficiency and possibly more serious errors such as crosstalk noise or missed connections. A conventional wave-vector triad method of analyzing the scattered beam errors leads readily to near-Bragg estimates of the output angular misalignment. However, the READ wave-vector triads appear to indicate a possible wavelength shift in the output beam even with a Bragg-matched READ wavelength, …

Yttria Stabilized Zirconia Buffered Silicon: Substrates For Ybco Microwave Applications, Philip D. Brown

FIU Electronic Theses and Dissertations

The use Yttria-Stabilized Zirconia (YSZ) as a buffer layer for YBa₂Cu₃O_7-x (YBCO) thin films on (100) silicon (Si) substrates is investigated. YSZ was grown using on-axis pulsed D.C. (PDC) and R.F. magnetron sputtering from a 99.9% pure YSZ target [(Y₂O₃)_0.08(ZrO₂)_0.92]. Sputtering was carried out in Argon/Oxygen atmosphere at total pressures ranging from 6 to 320 mTorr containing 0.1 to 10% Oxygen. Substrate temperatures were varied from 300° C to 900° C. (111), (100) and mixed (100) and (111) oriented YSZ films were produced …

Various Noise Sources And Noise Reduction Techniques In Instrumentation, Raman K. Attri

Raman K. Attri

Noise is the biggest environmental factor, which determines if a system will operate reliably in practice. Noise can be random or repetitive, occurring continuously or in isolated burst. It may affect current or voltage and may occur at any frequency from DC to very high frequencies. A particular source may generate noise over narrow or wide band of frequencies. Some time the effect of noise on the system performance can be very drastic.

Space-Time Reduced Rank Methods And Cfar Signal Detection Algorithms With Applications To Hprf Radar, Tareq F. Ayoub

Dissertations

In radar applications, the statistical properties (covariance matrix) of the interference are typically unknown a priori and are estimated from a dataset with limited sample support. Often, the limited sample support leads to numerically ill-conditioned radar detectors. Under such circumstances, classical interference cancellation methods such as sample matrix inversion (SMI) do not perform satisfactorily. In these cases, innovative reduced-rank space-time adaptive processing (STAP) techniques outperform full-rank techniques. The high pulse repetition frequency (HPRF) radar problem is analyzed and it is shown that it is in the class of adaptive radar with limited sample support. Reduced-rank methods are studied for the …

A Low-Cost High-Speed Twin-Prefetching Dsp-Based Shared-Memory System For Real-Time Image Processing Applications, Charalambos Stephanou Christou

Dissertations

This dissertation introduces, investigates, and evaluates a low-cost high-speed twin-prefetching DSP-based bus-interconnected shared-memory system for real-time image processing applications. The proposed architecture can effectively support 32 DSPs in contrast to a maximum of 4 DSPs supported by existing DSP-based bus- interconnected systems. This significant enhancement is achieved by introducing two small programmable fast memories (Twins) between the processor and the shared bus interconnect. While one memory is transferring data from/to the shared memory, the other is supplying the core processor with data. The elimination of the traditional direct linkage of the shared bus and processor data bus makes feasible the …

Performance Improvements In Wireless Cdma Communications Utilizing Adaptive Antenna Arrays, Weichen Ye

Dissertations

This dissertation studies applications of adaptive antenna arrays and space-time adaptive processing (STAP) in wireless code-division multiple-access (CDMA) communications. The work addresses three aspects of the CDMA communications problems: (I) near-far resistance, (2) reverse link, (3) forward link. In each case, adaptive arrays are applied and their performance is investigated.

The near-far effect is a well known problem which affects the reverse link of CDMA communication systems. The near-far resistance of STAP is analyzed for two processing methods: maximal ratio combining and optimum combining. It. is shown that while maximal ratio combining is not near-far resistant, optimum combining is near-far …

Petri Net Modeling And Performance Analysis Of Can Fieldbus, Ji-Qiong Zhou

Theses

The CAN FB (Controller Area Network FieldBus) has been in existence for ten years. It supports automated manufacturing and process control environments to interconnect intelligent devices such as valves, sensors, and actuators. CAN FieldBus has a high bit rate and the ability to detect errors. It is immune to noise and resistant to shock, vibration, and heat. Two recently introduced mechanisms, Distributed Priority Queue (DPQ) and Priority Promotion (PP) enable CAN FieldBus networks to share out the system bandwidth and grant ail upper bound on the transmission times so as to meet the requirements in real-time communications. Modeling and analysis …

Collaborative Filtering In Tv Recommender, Elizabeth Podberezniak

Theses

The thesis describes different types of collaborative filtering methods to filter information from the large amount available and presents examples of such systems in different domains. It focuses on automated collaborative filtering to generate personalized recommendation of information.

Different variations of the automated collaborative filtering scheme are developed and analyzed in the thesis. An additional adjustment of the predicted score is implemented in order to improve precision of the recommendation. Different combinations of parameters are analyzed to maximize system effectiveness.

The data for the analysis was gathered through TV Recommender, a World Wide Web system developed for the thesis. The …

Investigation Of Pathophysiologic Trends In Caucasian And Afro-American Hypertensives By Means Of Heart Rate Variability Recording During Upright Tilt-Table Testing, Jose F. Torrealba

Theses

The incidence of hypertension is more prevalent among the Afro-American population than the Caucasians and there is not a satisfactory explanation for this discrepancy.

Heart Rate Variability (HRV) has been demonstrated to reflect the relative activities of the sympathetic (SMP) and parasympathetic (PSMP) divisions of the autonomic nervous system (ANS).

This study consisted in comparing the HRV, as well as the blood pressure (BP) of four different groups during up-right tilt table testing. The subjects were grouped by age, gender, race and health condition. Analysis in time and frequency domain was applied to the data. In the frequency domain, the …

Radiative Properties Of Silicon, Anamika Patel

Theses

The objective of this thesis was 1) to study the radiative properties of silicon in the wavelength range of 1 to 20 microns and temperature range of 30 to 1000°C for the development of a multi-wavelength pyrometer 2) to develop a [sic] methodologies for deconvolution of the measured optical properties to yield fundamental optical constants of bulk materials. A novel spectral emissometer has been utilized for measurement of the temperature dependent radiative properties of silicon. The temperature determination capability of the emissometer was tested and verified using a standard thermocouple embedded in a silicon wafer. The temperature measurement accuracy, with …

Design, Fabrication And Characterization Of Silicon Microlenses For Ir-Ccd Image Sensors, Dhiren Pattnaik

Theses

There is a growing trend in the study of Focal Plane Arrays(FPAs) of very small microlenses, used for a wide variety of imaging and sensing applications, to increase optical efficiency. Present day sensor technology might take a different direction altogether with the development of compact, high quality, high resolution imaging microlenses, which could make the fill factor >90%. A method to increase light sensitivity of Interline Transfer(IT) type image sensors is to position microlens FPAs on top of the image sensors. FPAs are structures of small lenses which focus the incoming light on the photo sensitive part of the image …

Modified Multiple Model Adaptive Estimation (M3Ae) For Simultaneous Parameter And State Estimation, Mikel M. Miller

Theses and Dissertations

In many estimation problems, it is desired to estimate system states and parameters simultaneously. However, inherent to traditional estimation architectures of the past, the designer has had to make a trade-off decision between designs intended for accurate state estimation versus designs concerned with accurate parameter estimation. This research develops one solution to this trade-off decision by proposing a new architecture based on Kalman filtering (KF) and Multiple Model Adaptive Estimation (MMAE) techniques. This new architecture, the Modified-MMAE (M³AE), exploits the benefits of an MMAE designed for accurate parameter estimation, and yet performs at least as well in state …

Microengineered Sensor Devices With Field Emission Electron Sources, Chao Sun

Dissertations

This dissertation describes the design, simulation, fabrication, and characterization of a microengineered pressure sensor device and a microengineered mass spectrometer device, both of which use field emission cathode tip arrays as electron sources. VLSI and MEMS process techniques are used to scale down the dimensions from existing vacuum pressure sensors and mass spectrometers.

The microengineered pressure sensor device is fabricated on a silicon substrate approximately 1cm by 1cm. It consists of an electron source in the form of cathode tip array structure, an electron accelerating space which includes a gas ionization volume, and an ion collection electrode. The electrons emitted …

Performance Analysis Of The Interference Adaptation Dynamic Channel Allocation Technique In Wireless Communication Networks, Ziqiang Xu

Dissertations

Dynamic channel allocation (DCA) problem is one of the major research topics in the wireless networking area. The purpose of this technique is to relieve the contradiction between the increasing traffic load in wireless networks and the limited bandwidth resource across the air interface. The challenge of this problem comes from the following facts: a) even the basic DCA problem is shown to be NP-complete (none polynomial complete); b) the size of the state space of the problem is very large; and c) any practical DCA algorithm should run in real-time.

Many heuristic DCA schemes have been proposed in the …

Orthogonal Transmultiplexers : Extensions To Digital Subscriber Line (Dsl) Communications, Xueming Lin

Dissertations

An orthogonal transmultiplexer which unifies multirate filter bank theory and communications theory is investigated in this dissertation. Various extensions of the orthogonal transmultiplexer techniques have been made for digital subscriber line communication applications.

It is shown that the theoretical performance bounds of single carrier modulation based transceivers and multicarrier modulation based transceivers are the same under the same operational conditions. Single carrier based transceiver systems such as Quadrature Amplitude Modulation (QAM) and Carrierless Amplitude and Phase (CAP) modulation scheme, multicarrier based transceiver systems such as Orthogonal Frequency Division Multiplexing (OFDM) or Discrete Multi Tone (DMT) and Discrete Subband (Wavelet) Multicarrier …

Enhanced Terahertz Pulse Generation And Detection Using Electric Field Singularities In Photo-Conducting Antennas, Yi Cai

Dissertations

In recent years, generation of ultra-short electromagnetic pulses with frequency components in the terahertz (THz) range has been achieved by various techniques. Among those different methods, photo-conducting antennas have proven to be the most efficient source of THz radiation. THz spectrometers utilizing such photo-conducting antennas as transmitters and receivers are meanwhile routinely used for spectroscopic studies in the frequency regime between 0.1 to 5THz, which can be covered by neither conventional optical nor microwave spectrometers. However, THz emission power from the existing photo-conducting antenna is not sufficient for many applications (such as electro-optic sampling for real time THz detection and …

Design And Characterization Of Ultra High Frame Rate Burst Image Sensors, Rakesh K. Kabra

Dissertations

This thesis research was aimed at investigating and designing novel architectures required for ultra high frame rate (UHFR) imagers capable of operating at frame rates in excess of 10⁶ frames/sec. To demonstrate the feasibility of these architectures, a 180 x 180 element UHFR-I imager was designed and fabricated. The imager chip stored the latest 32 frames at its on-chip memory locations rather than performing a continuous readout. It was demonstrated that this architecture approach could achieve a frame acquisition rate of 2 x 10⁶ frames/sec. Additionally, other novel design features were incorporated to minimize optical cross talk and …

Dual Material Gate Field Effect Transistor (Dmg-Fet), Wei Long

Dissertations

Improving performance and suppressing short channel effects are two of the most important issues in present field effect transistors development. Hence, high performance and long channel like behaviors are essential requirements for short channel FETs. This dissertation focuses on new ways to achieve these significant goals. A new field effect transistor - dual material gate FET (DMG-FET) - is presented for the first time. The unique feature of the DMG-FET is its gate which consists of two laterally contacting gate materials with different work functions. This novel gate structure takes advantage of material work function difference in such a way …

Decentralized Reliable Control For Large-Scale Lti Systems, Zhengfang Chen

Dissertations

Reliable control concerns the ability of closed loop system to maintain stability and regulation properties during arbitrary sensor, controller, and actuator failure. Reliable control research has been an active research topic for more than 10 years.

Recent approach for reliable control includes the H∞ method, the algebraic factorization design, and the robust servomechanism control. These methods have been surveyed and discussed in this thesis with the robust servomechanism control methodology serving as the basis of the research development of this work.

In this thesis, the reliable control for large-scale, multi-input/output linear system is considered. Two concepts of reliable control …

Cantilever Beam Microactuators With Electrothermal And Electrostatic Drive, Murat M. Okyar

Dissertations

Microfabrication provides a powerful tool for batch processing and miniaturization of mechanical systems into dimensional domain not accessible easily by conventional machining. CMOS IC process compatible design is definitely a big plus because of tremendous know-how in IC technologies, commercially available standard IC processes for a reasonable price, and future integration of microma-chined mechanical systems and integrated circuits. Magnetically, electrostatically and thermally driven microactuators have been reported previously. These actuators have applications in many fields from optics to robotics and biomedical engineering.

At NJIT cleanroom, mono or multimorph microactuators have been fabricated using CMOS compatible process. In design and fabrication …

Micro Electromechanical Relays And Their Application In Variable Inductor Networks, Shifang Zhou

Dissertations

A family of microrelay devices together with integrated inductor networks has been designed, simulated, fabricated and experimental characterized. These switched networks utilize microelectromechanical systems (MEMS) as a fabrication technology and take advantage of the economies of semiconductor cleanroom batch-processing.

A new type of microrelay has been developed using a suspended TaSi₂/SiO₂ bimorph cantilever beam, gold-to-gold electrical contact, aluminum as sacrificial layer, and a combined thermal and electrostatic means of actuation. For the first time a micro variable inductor network which is digitally controlled by microrelays has been demonstrated. A test structure for electrical micro contact characterization has …

Investigation Of Optical Properties Of Inp, Ain And Sapphire For Applications In Non-Contact Semiconductor Process Monitoring, Rajasekhar Velagapudi

Theses

The objective of this thesis was to develop a reliable multi-wavelength pyrometer for simultaneous measurement of the wafer temperature and its optical properties in the wavelength range of 1 to 20 microns and temperature range of 30 to 1500° C. The spectral emissometer has been utilized for measurement of the temperature dependent optical properties of InP, AlN and Sapphire. The experimental results presented in this thesis showed that the measurement of high temperature optical properties could be performed reliably with a novel approach using the spectral ernissometer. The temperature determination capability of the emissometer was tested and verified using a …

Performance Enhancement Of Linear Robotic Workcell Using Dsp Based Control, Kedar Arvind Godbole

Theses

Robotic Controllers have for the major part been computer implementations of PID or similar controllers. In this thesis DSP based control of a Robotic Workcell is presented. The control algorithms used with the DSP based controller are Input Shaping and also State Feedback. Input Shaping is a Feed Forward strategy for eliminating vibration under certain conditions. In this thesis Input Shaping is applied to the performance enhancement of a linear robot system. Although feedback control strategies offer higher accuracy and are much more robust, feedforward strategies offer possibilities for improving the response time. Input Shaping is successfully applied to the …

A Design-For Retirement Rating Model For Environmentally Conscious Products, Xin He

Theses

Design-For-Retirement is a concept that allows one to design a product such that its retirement time and post-life treatment are optimized to lead to the minimum environmental impact and maximum financial gain. Retired product parts or subassemblies face three primary multi-lifecycle engineering treatments. The first one is to recondition them for reuse in the next lifecycle. The second one is to convert their post life parts into a material form for recycling back into new parts. The last is to dump or landfill them. Each option has a significantly different environmental cost-benefit ratio. Another important concern is the dismantling process …