Engineering Commons^™

New Neuron Model For Simulating Rotating Electrical Machines And Load Forecasting Problems, D. K. Chaturvedi, P. S. Satsangi, P. K. Kalra

D. K. Chaturvedi Dr.

The existing neuron structure has an aggregation function (usually summation) and its transformation through non-linear filter or squashing or thresholding functions. Such structure of neural networks has a number of disadvantages like large number of neurons, hidden layers and huge training data required for complex function approximations. The present paper proposes new neuron models to overcome the above problems in the existing neural networks. The model has been developed and tested for modelling of electrical machines like DC motor, induction motor and synchronous generator and load forecasting problems using different new neuron models in the neural network like S neuron …

Knowledge Based Neural Network For Voltage Contingency Selection And Ranking, Sn Singh, L Srivastava, Jd Sharma

SN Singh PhD

No abstract provided.

Low-Frequency Noise In N-Gan With High Electron Mobility, M. E. Levinshtein, S. L. Rumyantsev, D. C. Look, R. J. Molnar, M. Asif Khan, Grigory Simin, V. Adivarahan, M. S. Shur

Faculty Publications

We report on the results of measurements of low frequency noise in n-type gallium nitride (GaN) grown on sapphire with 300 K electron mobility of 790 cm²/V s. The noise spectra have the form of 1/f noise with a Hooge parameter α of approximately 5×10⁻². This value of α is two orders of magnitude smaller than that observed before in n-GaN. The obtained results show that the level of flicker noise in GaN, just like that in GaAs and Si, strongly depends on the structural perfection of the material (the amplitude of the 1/f …

Piezoelectric Doping In Alingan/Gan Heterostructures, M. Asif Khan, J. W. Yang, Grigory Simin, R. Gaska, M. S. Shur, A. D. Bykovski

Faculty Publications

We report on the piezoelectricdoping and two-dimensional (2D) electron mobility in AlInGaN/GaN heterostructures grown on 6H–SiC substrates. The contribution of piezoelectricdoping to the sheet electron density was determined using an In-controlled built-in strain-modulation technique. Our results demonstrate that in strained AlGaN/GaN heterostructures, the piezoelectric field generates at least 50% of the 2D electrons. The strain modulation changes the potential distribution at the heterointerface, which, in turn, strongly affects the 2D electron mobility, especially at cryogenic temperatures. The obtained results demonstrate the potential of strain engineering and piezoelectricdoping for GaN-based electronics.

Load Frequency Control: A Generalized Neural Network Approach, D. K. Chaturvedi, P. S. Satsangi, P. K. Kalra

D. K. Chaturvedi Dr.

Variation in load frequency is an index for normal operation of power systems. When load perturbation takes place anywhere in any area of the system, it will affect the frequency at other areas also. To control load frequency of power systems various controllers are used in different areas. but due to non-linearities in the system components and alternators, these controllers cannot control the frequency quickly and efficiently. Simple neural networks which are in common use at present have various drawbacks like large training time, requirement of large number of neurons, etc. The present work deals with the developmetn of a …

Detection And Robustness Of Digital Image Watermarking Signals : A Communication Theory Approach, George F. Elmasry

Dissertations

The detection and robustness of the watermark signal is studied from a communications point of view. The contributions of this dissertation are presented in two parts. The first part, which covers the detection aspect, introduces a new digital image watermarking approach that embeds meaningful information in a copyright protection watermark signal; demonstrates the need to approach the watermark signal as a power-constrained signal; studies the relationship between the watermark signal dimension and the image capacity to the signal; explains the similarities and differences between detecting the watermark signal and detecting a signal over a spread-spectrum communication channel; and analyzes the …

Variable Gain Control Of Brushless Dc Motor Control With Low Resolution Sensors, Chung-Hsiang Wang

Theses

In this work, feasibility of using low cost, low resolution sensor for high performance brushless dc (BLDC) motor speed control is investigated. Conventional control, using a tachometer or high resolution encoder, suffers from drawbacks such as high cost, large physical volume, and high sensor processing bandwidth. On the other hand, sensorless BLDC motor, appealing in its hardware simplicity, does not provide sufficient fast performance. Using a standard low resolution sensor, such as a hall sensor or commutation encoder, a compromise between cost and performance can be obtained. However, the use of a low resolution sensor does pose a challenge to …

Emissivity Measurements And Modeling Of Silicon Related Materials, Vijay Krishnamurthy

Theses

The objective of the thesis was to study the radiative properties of silicon related materials for applications in rapid thermal proceesing. In particular, three distinct materials have been considered - Silicon, SIMOX and Tantalum.

The research highlights are Establishment of spectral emissometry as a novel, reliable and reproducible technique for a) Determination of wavelength and temperature dependent reflectivity, transmissivity, emissivity of silicon related materials and structures. The emissometer operates in the wavelength range of 1-20µm and temperature range of 300-1200K. b) Establishment of methodoligies to obtain the frnndemental constants. Effects of wavelength, temperature, total available free carriers by doping types …

Design Of An Instrumentation System To Record Distribution Profile Of Snow Layer Temperature For Modelling Of Snow Avalanche Forecast, Raman Attri

Raman K. Attri

The measurement of snow hydrological parameters is extremely important in developing a model for the predication of Snow avalanche as well as Snowmelt water in the rivers. When direct measurement of these parameters is practically difficult, its dependence on snow temperature is used to develop snow cover models. A robust model for avalanche forecasting requires a sophisticated instrumentation system which can measure the required temperature parameters at right data points within snow pack. A Snow Temperature Profile Sensing System along with Surface temperature Sensor has been designed to measure Snow temperature gradient, temperature distributions, and average temperature of snow pack, …

Implementation Of Linear Array Of Ultrasonic Transmitter-Receiver Transducers For Detection Of Non-Smooth Porous Surface, Raman K. Attri, Swaranjit Singh

Raman K. Attri

Level measurements, thickness measurement or remote surface detection using ultrasonic pulse transit method require that the target surface be at 90O to the incident beam so that reflected beam comes back at 180O angel to effectively use this method. This is perfectly true in case of flat, solid surface at right angle to the incident beam. But surface irregularities of a porous, non-smooth, uneven material such as snow cause penetration of incident wave into the surface, absorption of the incident energy, scatter of energy in many directions and further attenuation of reflected signal making it difficult to detect the reflected …

Differential Reflection Phase Shift Under Conditions Of Attenuated Internal Reflection, R. M.A. Azzam

Electrical Engineering Faculty Publications

The angle-of-incidence dependence of the differential reflection phase shift Δ between p and s polarizations is considered a function of the real and imaginary parts of the relative complex dielectric function ε of an interface in the domain of fractional optical constants, i.e., under conditions of internal reflection. The constraint on complex ε such that oscillatory and monotonic angular responses are obtained is determined. A sensitive and stable technique, which is based on attenuated internal reflection ellipsometry between the Brewster angle and the critical angle, is proposed for measuring small induced absorption (ε_i∼10⁻⁵) in the medium …

Laser Beam Profile Deformation Effect During Bragg Acousto-Optic Interaction: A Non-Paraxial Approximation, Ray S. Huang, Chen-Wen Tarn, Partha P. Banerjee, Doungchin Cao

Electrical and Computer Engineering Faculty Publications

It is commonly known that the spatial profiles of the diffracted light beams during Bragg acousto-optic interaction are distorted due to the Bragg angle selection mechanism. All the conventional studies on this effect use the paraxial approximation. But this approximation should be amended when the incident angle of the light is large enough that the diffracted light waves do not propagate closely along the optic axis of the acousto-optic diffraction system. By using a spatial Fourier transform approach, we rigorously study the light beam profile deformation effect of the diffracted light during the Bragg acousto-optic interaction beyond the paraxial approximation. …

Guest Editorial: Special Section On Acousto-Optic Devices And Optical Information Processing: Research And Developments, Partha P. Banerjee, Ting-Chung Poon

Electrical and Computer Engineering Faculty Publications

This guest editorial provides an overview of the topical area and an introduction to the articles featured in the special section.

Examination Of Beam Propagation In Misaligned Holographic Gratings And Comparison With The Acousto-Optic Transfer Function Model For Profiled Beams, Monish Ranjan Chatterjee, David D. Reagan

Electrical and Computer Engineering Faculty Publications

A transfer function formalism developed earlier for the propagation of profiled optical beams through acousto-optic Bragg cells is revisited and applied to a thick holographic grating. The results based on the holographic coupled wave model and the acousto-optic multiple scattering model are shown to be compatible, and equivalent parameters such as the Q and grating strength are defined for the two systems. Results for a Gaussian spatial profile are numerically computed and compared. For the holographic grating, a profiled beam may be interpreted as an angular misalignment or Bragg-angle mismatch problem. The case of Bragg-wavelength mismatch is also investigated for …

Gsis: A Conceptual Model For Web-Based Integration Of Information Technology With Geo-Scientific Instrumentation, Raman Attri

Raman K. Attri

Since a long time leading organisations have been advocating the need of implementation of IT in a centralised manner on the distributed geological data monitoring centres. In the era of IT, it is highly important to access, share and analyse related data on a common platform for fast retrieval of information in centralised as well as in distributed mode. In this article a concept to integrate Geo-Scientific Instrumentation systems to Information Technology has been highlighted. The vision to create a Geo-Scientific Information System (GSIS) would be an approach where a centralised web-enabled database of the data acquired & transmitted by …

Bistatic Radar Cross Section (Rcs) Characterization Of Complex Objects, Robert L. Eigel Jr.

Theses and Dissertations

This research addresses some phenomenological aspects of bistatic scattering from a complex object with an emphasis on specular, shadowing, dihedral, and cavity effects. Five targets are investigated for their simplicity and ability to highlight certain scattering phenomena. Direct measurements of scattered electromagnetic energy and simulation data is gathered for a frequency bandwidth of 6-18 GHz. Both ray tracing and scattering center approaches are used to describe the bistatic mechanisms. An appraisal of the effectiveness and utility of the monostatic-to-bistatic equivalence theorems (Kell's and Crispin's) and several commercial scattering prediction codes is also accomplished. Simulation data is generated from two different …

Adaptive Interference Cancelation Techniques For Multicarrier Modulated Systems, Matthijs A. Visser

Dissertations

Current wireline systems and wireless broadcasting systems employ multicarrier modulation (MCM). This includes the high-rate digital subscriber line (HDSL), digital audio broadcasting system (DAB) and the digital terrestrial television broadcasting system (dTTb). Multicarrier modulation is also envisioned for high-speed indoor wireless local area networks (WLAN). Additionally, multicarrier code division multiple access (MC-CDMA), a hybrid of orthogonal frequency division multiplexing (OFDM) and CDMA, is proposed for the downlink (base-to-mobile) of a 3rd generation wireless system as part of the IMT-2000 standardization process.

The performance of an MC-CDMA system--similar to a direct sequence CDMA (DS-CDMA) system--is limited by the presence of multiple …

On Scheduling Input Queued Cell Switches, Shizhao Li

Dissertations

Output-queued switching, though is able to offer high throughput, guaranteed delay and fairness, lacks scalability owing to the speed up problem. Input-queued switching, on the other hand, is scalable, and is thus becoming an attractive alternative. This dissertation presents three approaches toward resolving the major problem encountered in input-queued switching that has prohibited the provision of quality of service guarantees.

First, we proposed a maximum size matching based algorithm, referred to as min-max fair input queueing (MFIQ), which minimizes the additional delay caused by back pressure, and at the same time provides fair service among competing sessions. Like any maximum …

On-Line State And Parameter Estimation In Nonlinear Systems, David A. Haessig

Dissertations

On-line, simultaneous state and parameters estimation in deterministic, nonlinear dynamic systems of known structure is the problem considered. Available methods are few and fall short of user needs in that they are difficult to apply, their applicability is restricted to limited classes of systems, and for some, conditions guaranteeing their convergence don't exist.

The new methods developed herein are placed into two categories: those that involve the use of Riccati equations, and those that do not. Two of the new methods do not use Riccati equations, and each is considered to be a different extension of Friedland' s parameter observer …

Fdtd-Based Full Wave Co-Simulation Model For Hybrid Electromagnetic Systems, Tong Li

Dissertations

In high-frequency ranges, the present electronic design automation software has limited capabilities to model electromagnetic (EM) systems where there are strong field effects influencing their characteristics. In this situation, a full-wave simulation tool is desired for the analysis and design of high-speed and non-linear EM systems. It is necessary to explore the interaction between the field and electronic components during a transient process when field effects are more significant. The finite-difference time-domain (FDTD) technique receives growing attention in the area of EM system analysis and simulation due to its simplicity, flexibility and robustness. It is a full-wave simulation method that …

Observers For Discrete-Time Nonlinear Systems, Walter D. Grossman

Dissertations

Observer synthesis for discrete-time nonlinear systems with special applications to parameter estimation is analyzed. Two new types of observers are developed. The first new observer is an adaptation of the Friedland continuous-time parameter estimator to discrete-time systems. The second observer is an adaptation of the continuous-time Gauthier observer to discrete-time systems. By adapting these observers to discrete-time continuous-time parameter estimation problems which were formerly intractable become tractable.

In addition to the two newly developed observers, two observers already described in the literature are analyzed and deficiencies with respect to noise rejection are demonstrated. improved versions of these observers are proposed …

Vibration Control On Linear Robots With Digital Servocompensator, Roger Kobla Kwadzogah

Theses

Control application for active damping of structural vibrations and acoustic noise in mechanical systems is one of the engineering fields that can benefit from advances made in digital signal processors. This thesis project is one such application. It is about a vibration control at the loading point of a high speed linear robotic workcell. A lead zirconate titanate piezoelectric ceramic is used as the actuator and an accelerometer provides the sensing. From experimentally measured frequency response of this system, a shaping filter is designed and added on. The reshaped system is fitted with a third order transfer function design model. …

Development Of A Context-Specific Search Engine, An Executive Information System, And A Novel Www Ready External Cost Model, Amit V. Revankar

Theses

NJPIES is associated with Information Ecology and Sustainability, a holistic approach to environmental data collection, compilation, integration and provision that puts people, not technology, at the center of the environmental information world.

The first main goal of this project was to develop an algorithm and associated computer-based tool that could perform a lifecycle cost analysis for a model system. The application developed solved the primary problem associated with the lifecycle cost analysis of a product: it accounted for all costs (e.g., environmental costs such as ecological costs and health costs associated with emissions) of the activity. A lifecycle cost analysis …

Radiative Properties Of Ir Materials, Manish R. Babladi

Theses

The objective of this thesis is to study the radiative properties of materials of interest in the infrared range of wavelengths. In particular, three distinct materials have been considered here - Erbium oxide, alumina and quartz. Erbium oxide has unique selective line emission, which gives a high emittance at a particular wavelength and low emittance in the rest of the infrared spectrum. It has applications in the design and development of thermophotovoltaic (TPV) generators. Because of its selective emission properties, erbium oxide assists in concentrating the radiant energy into a narrow band near the bandgap energy of the TPV cell, …

Graphical User Interface For The Dsp : Using Texas Instruments Tms320c31 And Labview, Tahir Nazir

Theses

Digital Signal Processors (DSP's) have become very popular due to their ease of operation, economic value, adaptability and availability. However, the development environments for the DSP are still the archaic Assembly and C language programming. It is tedious, error prone and time consuming to develop and use DSP applications using these compared to Graphical User Interface development tools if available. In the modern age programming is very heavily done in object oriented graphical languages like the Visual C++ and Visual Basic. Windows also gives a good graphical user interface.

LAB VIEW with its readily available ensemble of good analysis, programming …

Vibration Control Of Ultra-High Precision Magnetic Leadscrew Using Recurrent Neural Network, Bhaskar Vinayak Dani

Theses

Ultra-high precision positioning is of strategic importance to modern industrial processes such as semiconductor manufacturing. Traditional drives with mechanical transmission elements exhibit nonlinearities such as friction, backlash and hysteresis which limit the system performance significantly. The magnetic leadscrew in this work belongs to the class of contactless drives which overcome the above mentioned limitations of contact-type drives. The operation is based on leadscrew/nut coupling but unlike mechanical Ieadscrews, the threads of the nut and the leadscrew are aligned magnetically and do not come in contact. Thus, "hard" nonlinearities are substantially reduced resulting in high precision and high resolution.

The dynamics …

A Signal Conditioning Approach For The Extraction Of The Oscillatory Petential From The Electroretinogram, Peter Haines Derr

Theses

The oscillatory potential (OP), a signal component of the electroretinogram (ERG), was investigated to determine correlation of the OP and pathological conditions of the inner retina. Large transients characterize the ERG. Such transients stimulate a filter's natural response. Since these responses can co-occur with the OP, a distorted OP will be extracted. A proposed signal windowing and padding technique for conditioning the ERG signal has been implemented for the extraction of a ntnimally distorted OP.

Windowing is used to capture only the OP period. The windowed ERG signal is then signal conditioned to generate initial values for the filter's state …

Development Of An Ion Source For Implantation Of Decaborane, Ravidath Gurudath

Theses

Future generations of Si technology will require ultra shallow junctions (tens of nm) in the drain and source regions of MOS transistors. Fabrication of such shallow p-type junctions requires implantation of boron at ultra low energies (≡1keV), below the limits of standard ion implantation technology. A proposed solution involves implantation of B₁₀H_X⁺ ions in which boron atoms carry less than 10% of the beam energy. Thus shallow implantation may be possible with standard ion implanters operating at tens of kV.

This thesis is a part of the feasibility study of this novel technology. The ionization of …

Dual Frequency Bi-Othogonally Polarized Antennas For Gps Applications, Anand Arun Mahale

Theses

Dual frequency bi-orthogonally polarized antenna to be used in Global Positioning System applications operating in Li (1575.42 ± 10.23 MHz) and L2 (1227.60 ± 10.23 MHz) Bands has been studied. To ensure compatibility with existing applications, the antenna size is limited in dimensions to 4.120" x 4.680" x 1.250" including the radome. Orthogonally placed two dual frequency probe excited patches were designed using a high dielectric constant substrate (ε r = 9.8 and thickness of 250 mils, Rogers TMM10i material) to obtain vertical and horizontal polarization for each band. The measured performance of this antenna showed good agreement with the …

Handoff Effect On Prma (Packet Reservation Multiple Access) In Micro-Cellular System, Dongsuk Park

Theses

PRMA(Packet Reservation Multiple Access) has been proposed for third generation wireless information network by Goodman et al. [5] [4]. Due to small micro cell radius mobile initiated handoff has been proposed to disperse the burden of BS(Base Station) [14]. Even though these frequent handoffs will not burden on BS, increased contends due to handoff will affect the over all performance of PRMA.

In this paper, we analyze the handoff effect on PRMA performance under micro-cellular system. Steady state speech terminal model with handoff is proposed.. Stabilities are derived based on proposed steady state terminal model[F(c_s)=M] and also increased …