Engineering Commons^™

Rate-Based End-To-End Congestion Control Of Multimedia Traffic In Packet Switched Networks, Mingsheng Peng, S. R. Subramanya, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes an explicit rate-based end-to-end congestion control mechanism to alleviate congestion of multimedia traffic in packet switched networks such as the Internet. The congestion is controlled by adjusting the transmission rates of the sources in response to the feedback information from destination such as the buffer occupancy, packet arrival rate and service rate at the outgoing link, so that a desired quality of service (QoS) can be met. The QoS is defined in terms of packet loss ratio, transmission delay, power, and network utilization. Comparison studies demonstrate the effectiveness of the proposed scheme over New-Reno TCP (a variant …

Device Structure Effects On Electrical Crosstalk In Backwall Illuminated Cmos Compatible Photodiode Arrays, Paul Vernon Jansz

Theses : Honours

This research has made a comparative investigated of crosstalk in backside illuminated and frontside illuminated single junction photodiode and vertical double junction photodiode CMOS compatible pixels, using a commercial 2D device simulation package, SEMICAD DEVICE (1994). Comparison of pixel total, electron and hole quantum efficiency response and Absorption Volume data is undertaken. This is so that the underlying carrier drift-diffusion dynamics responsible for optimal pixel response resolution may be qualitatively understood, allowing prediction of even more optimal photodiode pixel configurations. The effect of varying the double junction and single junction photodiode pixel's geometry on response resolution is considered. Only for …

Efficient Embedding Of Virtual Hypercubes In Irregular Wdm Optical Networks, Guru Prasad P. Kithlanagamangala

LSU Master's Theses

This thesis addresses one of the important issues in designing future WDM optical networks. Such networks are expected to employ an all-optical control plane for dissemination of network state information. It has recently been suggested that an efficient control plane will require non-blocking communication infrastructure and routing techniques. However, the irregular nature of most WDM networks does not lend itself to efficient non-blocking communications. It has been recently shown that hypercubes offer some very efficient non-blocking solutions for, all-to-all broadcast operations, which would be very attractive for control plane implementation. Such results can be utilized by embedding virtual structures in …

Arithmetic Logic Unit (Alu) Design Using Reconfigurable Cmos Logic, Chandra Srinivasan

LSU Master's Theses

Using the reconfigurable logic of multi-input floating gate MOSFETs, a 4-bit ALU has been designed for 3V operation. The ALU can perform four arithmetic and four logical operations. Multi- input floating gate (MIFG) transistors have been promising in realizing increased functionality on a chip. A multi- input floating gate MOS transistor accepts multiple inputs signals, calculates the weighted sum of all input signals and then controls the ON and OFF states of the transistor. This enhances the transistor function to more than just switching. This changes the way a logic function can be realized. Implementing a design using multi-input floating …

Generalized D-Sequences And Their Applications To Cdma Systems, Radhika Vaddiraja

LSU Master's Theses

Code Division Multiple Access (CDMA), a form of spread spectrum communications is used widely in cellular telephony. CDMA systems employ Walsh-Hadamard orthogonal codes, jointly with Pseudo-Noise (PN) sequences, Gold sequences and Kasami sequences to achieve spreading. This thesis investigates properties of generalized d-sequences and their applications as spreading sequences in CDMA systems. The correlation properties of these sequences are studied. The autocorrelation function of these sequences is not exactly two-valued but the cross correlation values are zero for certain class of these sequences. The zero cross correlation property can be useful in solving the near-far problem in CDMA communication systems, …

Circuitry For A Remotely Powered Bio-Implantable Gastric Electrical Stimulation System, Satish Kona

LSU Master's Theses

Power to bio-implantable devices is usually supplied through a battery implanted with the system or through wires extending to an outside power source. The latter case with wires protruding out of the body can be unaesthetic in appearance and can cause infection. In this research, we consider an alternative way to power a bio-implantable microsystem. It involves using rechargeable lithium batteries. Here, power is delivered remotely to charge implanted battery or batteries. This approach avoids periodic surgery necessary for battery replacement. It also does not tie a person to an external power source at all times. This improves patient’s quality …

Adaptive Image Filtering Using Run-Time Reconfiguration, Nitin Srivastava

LSU Master's Theses

This thesis implements an adaptive linear smoothing image filtering algorithm, on a Virtex™-E FPGA using run-time reconfiguration (RTR). An adaptive filter uses a filtering window that runs over the entire image pixel-by-pixel, generating new (filtered) values of the pixels. As the name suggests, an adaptive filter can adapt to the varying nature of an image by adjusting the coefficients of the filtering window depending upon the local variance in the intensity values of pixels. It filters an image in a non-uniform fashion providing greater smoothing in largely uniform areas of the image and lesser smoothing when it encounters edges and …

Orthogonal Frequency Division Multiplexing Modulation And Inter-Carrier Interference Cancellation, Yao Xiao

LSU Master's Theses

The Orthogonal Frequency Division Multiplexing (OFDM) technique, wireless channel models, and a pair of new intercarrier interference self-cancellation methods are investigated in this thesis. The first chapter addresses the history of OFDM, along with its principles and applications. Chapter two consists of three parts: the principal, the modern OFDM models, and the Peak to Average Power Ratio (PAPR) problem. Chapter two also summarizes possible PAPR solutions. Chapter three discusses a series of well-known wireless channel models, as well as the general formula for wireless channels. In Chapter four, ICI problem has been discussed, along with its existing solutions. Chapter five …

Design Of Power Efficient Multicast Algorithms For Sparse Split Wdm Networks, Kavitha Devi Buddharaju

LSU Master's Theses

Recent years witnessed tremendous increase in data traffic as new Internet applications were launched. Optical networks employing recent technologies such as DWDM and EDFA`s emerged as the most prominent and most promising solutions in terms of their ability to keep with the demand on bandwidth. However for a class of applications bandwidth is not the only important requirement, These applications require efficient multicast operations. They include data bases, audio/video conferencing, distributed computing etc. Multicasting in the optical domain however has its own unique set of problems. First, an optical signal can be split among the outputs of a node but …

Design Of Optimal Equalizers And Precoders For Mimo Channels, Lijuan Li

LSU Doctoral Dissertations

Channel equalization has been extensively studied as a method of combating ISI and ICI for high speed MIMO data communication systems. This dissertation focuses on optimal channel equalization in the presence of non-white observation noises with unknown PSD but bounded power-norm. A worst-case approach to optimal design of channel equalizers leads to an equivalent optimal H-infinity filtering problem for the MIMO communication systems. An explicit design algorithm is derived which not only achieves the zero-forcing (ZF) condition, but also minimizes the RMS error between the transmitted symbols and the received symbols. The second part of this dissertation investigates the design …

On Implementing Dynamically Reconfigurable Architectures, Hatem Mahmoud El-Sayed El-Boghdadi

LSU Doctoral Dissertations

Dynamically reconfigurable architectures have the ability to change their structure at each step of a computation. This dissertation studies various aspects of implementing dynamic reconfiguration, ranging from hardware building blocks and low-level architectures to modeling issues and high-level algorithm design. First we derive conditions under which classes of communication sets can be optimally scheduled on the circuit-switched tree (CST). Then we present a method to configure the CST to perform in constant time all communications scheduled for a step. This results in a constant time implementation of a step of a segmentable bus, a fundamental dynamically reconfigurable structure. We introduce …

Denoising Techniques - A Comparison, Sarita Veera Dangeti

LSU Master's Theses

Visual information transmitted in the form of digital images is becoming a major method of communication in the modern age, but the image obtained after transmission is often corrupted with noise. The received image needs processing before it can be used in applications. Image denoising involves the manipulation of the image data to produce a visually high quality image. This thesis reviews the existing denoising algorithms, such as filtering approach, wavelet based approach, and multifractal approach, and performs their comparative study. Different noise models including additive and multiplicative types are used. They include Gaussian noise, salt and pepper noise, speckle …

Modeling Intracranial Fluid Flows And Volumes During Traumatic Brain Injury To Better Understand Pressure Dynamics, Wayne W. Wakeland, James Mcnames, Mateo Aboy, D. Hollemon, Brahm Goldstein

Complex Systems Faculty Publications and Presentations

See additional files below for the Presentation.

We describe a computer model of intracranial pressure (ICP) dynamics that evaluates clinical treatment options for elevated ICP during traumatic brain injury (TBI). The model uses fluid volumes as primary state variables and explicitly models fluid flows as well as the resistance, compliance, and pressure associated with each intra - and extracranial compartment (arteries and arterioles, capillary bed, veins, venous sinus, ventricles, and brain parenchyma). The model evaluates clinical events and therapies such as intra - and extra-parenchymal hemorrhage, cerebral edema, cerebrospinal fluid drainage, mannitol administration, head elevation, and mild hyperventilation. The model …

Use Of Machine Learning Based On Constructive Induction In Dialogs With Robotic Heads, Marek Perkowski, Tsutomu Sasao, Atsumu Iseno, Uland Wong, Martin Lukac, David Ng, Miranda Fix, Karl Kuchs, Mikhail Pivtoraiko, Michele Folgheraiter

Electrical and Computer Engineering Faculty Publications and Presentations

Paper presents our research progress and experiences related to designing inexpensive natural-size humanoid caricature and realistic robot heads - actors for robot theatre, agents for advertisement, education and entertainment. We concentrate on Machine Learning techniques used to teach robots behaviors, natural language dialogs and facial gestures.

A Hierarchical Approach To Computer-Aided Design Of Quantum Circuits, Marek Perkowski, Martin Lukac, Pawel Kerntopf, Mikhail Pivtoraiko, Michele Folgheraiter, Yong Woo Choi, Jung-Wook Kim, Dongsoo Lee, Woong Hwangbo, Hyungock Kim

Electrical and Computer Engineering Faculty Publications and Presentations

A new approach to synthesis of permutation class of quantum logic circuits has been proposed in this paper. This approach produces better results than the previous approaches based on classical reversible logic and can be easier tuned to any particular quantum technology such as nuclear magnetic resonance (NMR). First we synthesize a library of permutation (pseudobinary) gates using a Computer-Aided-Design approach that links evolutionary and combinatorics approaches with human experience and creativity. Next the circuit is designed using these gates and standard 1*1 and 2*2 quantum gates and finally the optimizing tautological transforms are applied to the circuit, producing a …

Reversible Logic Synthesis With Cascades Of New Family Of Gates, Mozammel H.A. Khan, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

Reversible circuits are currently on of top approaches to power minimization and the one whose importance will be only growing with time. In this paper, the well known Feynman gate is generalized to k*k gate and a new generalized k*k family of reversible gates is proposed. A synthesis method for multi-output SOP function using cascades of the new gate family is presented. For utilizing the benefit of product sharing among the output functions, two graph-based data structures are used. Another synthesis method for AND-OR-EXOR function using cascades of the new gate family and generalized Feynman gate is also presented. Synthesis …

Source Motion Mitigation For Adaptive Matched Field Processing, Lisa M. Zurk, Nigel Lee, James Ward

Electrical and Computer Engineering Faculty Publications and Presentations

Application of adaptive matched field processing to the problem of detecting quiet targets in shallow water is complicated by source motion, both the motion of the target and the motion of discrete interferers. Target motion causes spreading of the target peak, thereby reducing output signal power. Interferer motion increases the dimensionality of the interference subspace, reducing adaptive interference suppression. This paper presents three techniques that mitigate source motion problems in adaptive matched field processing. The first involves rank reduction, which enables adaptive weight computation over short observation intervals where motion effects are less pronounced. The other two techniques specifically compensate …

Traffic Engineering In Multiprotocol Label Switching Networks, Chung-Yu Wei

LSU Master's Theses

The goal of Traffic Engineering is to optimize the resource utilization and increase the network performance. Constraint-based routing has been proposed as an networks effective approach to implement traffic engineering in Multiprotocol Label Switching. In this thesis, we review several algorithms on constraint-based routing from the literature and point out their advantages and disadvantages. We then propose several algorithms to overcome some of the shortcomings of these approaches. Our algorithms are specifically suitable for large densely connected networks supporting both Quality of Service traffic and the Best Effort traffic. In large networks the size of the MPLS label space in …

Remote Power Delivery And Signal Amplification For Mems Applications, Sunitha Kopparthi

LSU Master's Theses

Device such as remotely located sensors and bio-implanted devices such as gastric pacer require power for operation. The most commonly used energy source for such devices is a battery cell included in the receiver capsule. Wires can also be used with an external power source but in some applications have serious limitations. This work examines a wireless power transmitter and receiver system to provide power to a remotely located microsystem. Inductive power coupling is the method of choice. For gastric pacer application, external transmitter coil can be worn around the waist as a belt and the receiver coil can be …

Common- And Differential-Mode Signaling And Filtering, Zhe Li

Masters Theses

"Common-mode chokes are widely used as suppression filters against interference of common-mode noise in high-speed differential signaling. This thesis focuses on investigating the characteristics of common-mode chokes. Mixed-mode S-parameters are presented as a useful concept for explaining the modal operation of differential circuits.

Three methods for measuring common-mode and differentia-mode S-parameters of common-mode chokes are demonstrated. The three methods involve (1) ABCD chain matrix, 2) using hybrid couplers and 3) modal decomposition. Each measurement method provides a specific level of accuracy. The modal decomposition method can work up to 10GHz.

SPICE equivalent circuit model of common-mode chokes and the extraction …

An Invariance Transformation Algorithm For Defect Characterization Of Ultrasonic Signals For The Nondestructive Evaluation Of Concrete, Michael Dominic Ciocco

Theses and Dissertations

Nondestructive evaluation (NDE) techniques offer cost-effective strategies for monitoring the integrity of a variety of civil infrastructure, such as natural gas and sewer pipelines, without the need to take the system off-line. However, interpretation of NDE signals in terms of the location, size, and shape of underlying flaws in the material being inspected is fraught with difficulty. Typically, variations in the testing signal due to operational parameters have created a significant challenge for defect characterization. This thesis proposes, develops, and validates a defect characterization algorithm that compensates for operational variables and maps the test signal to a visual defect profile. …

Automated Segmentation Of Radiodense Tissue In Digitized Mammograms Using A Constrained Neyman-Pearson Classifier, Jeremy Thomas Neyhart

Theses and Dissertations

Breast cancer is the second leading cause of cancer related mortality among American women. Mammography screening has emerged as a reliable non-invasive technique for early detection of breast cancer. The radiographic appearance of the female breast consists of radiolucent (dark) regions and radiodense (light) regions due to connective and epithelial tissue. It has been established that the percentage of radiodense tissue in a patient's breast can be used as a marker for predicting breast cancer risk. This thesis presents the design, development and validation of a novel automated algorithm for estimating the percentage of radiodense tissue in a digitized mammogram. …

Derivation Of An Expression That Defines The Pulling Forces In Relays With Small Operating Gaps, D. J. Chambega

Tanzania Journal of Engineering and Technology (TJET)

This paper derives an expression that defines magnitude of the pulling force developed in relays with small operating gaps, that is, when the length of the operating gap in between the yoke and the armature is small as compared to the area of the poles at the yoke. To obtain the expression, saturation of the core material is not considered. Results from the expression are then compared with those obtained experimentally. The comparison is found to deliver acceptable accuracy.

Milliwatt Power Deep Ultraviolet Light-Emitting Diodes Over Sapphire With Emission At 278 Nm, J. P. Zhang, A. Chitnis, V. Adivarahan, S. Wu, V. Mandavilli, R. Pachipulusu, M. Shatalov, Grigory Simin, J. W. Yang, M. Asif Khan

Faculty Publications

We report on AlGaN multiple-quantum-well (MQW)-based deep ultraviolet light-emitting diodes over sapphire with peak emission at 278 nm. A new buffer layer growth process was used to reduce the number of defects and hence the nonradiative recombination. The improved material quality and carrier confinement resulted in pulsed powers as high as 3 mW at 278 nm and a significantly reduced deep-level-assisted long-wavelength emission.

Chaotic Free-Space Laser Communication Over Turbulent Channel, N. F. Rulkov, Mikhail Vorontsov, L. Illing

Electro-Optics and Photonics Faculty Publications

The dynamics of errors caused by atmospheric turbulence in a self-synchronizing chaos-based communication system that stably transmits information over a ∼5  km free-space laser link is studied experimentally. Binary information is transmitted using a chaotic sequence of short-term pulses as a carrier. The information signal slightly shifts the chaotic time position of each pulse depending on the information bit. We report the results of an experimental analysis of the atmospheric turbulence in the channel and the impact of turbulence on the bit-error-rate performance of this chaos-based communication system.

A Reversible Three-Phase Step Up/Down Switching Mode Rectifier, Jenn-Jong Shieh

Journal of Marine Science and Technology–Taiwan

In this paper, focus on the null space vector duty cycle control, a reversible three-phase step up/down switching mode rectifier is proposed attain clean sinusoidal input current, unity power factor, bidirectional power flow, step up/down output DC voltage and insensitivity for a voltage input. In addition, a precise simulation model is proposed to simulation by using PC software tools. Finally, some simulation and experimental results are presented for verification.

Buffer Interference Architecture, Vladimir I. Prodanov

Electrical Engineering

An up to 3× breakdown voltage tristate capable integrated circuit CMOS buffer includes a level shifter circuit and a driver circuit. The driver stage includes a series connected n-channel and p-channel cascode stacks, each including at least three transistors. Dynamic gate biasing is provided for the third n-channel and p-channel cascode transistors to prevent voltage overstress of the cascode transistors. The level shifter circuit includes at least one pseudo N-MOS inverter including an input transistor, a protective cascode stack including at least one n-channel cascode transistor, and a load transistor. The level shifter provides at least one voltage shifted input …

An Assessment Of Seawinds On Quikscat Wind Retrieval, David Draper, David G. Long

Faculty Publications

The scatterometer ocean wind retrieval process produces several possible solutions or ambiguities at each point, requiring a separate ambiguity selection step to infer a unique wind vector field. An ambiguity selection error occurs when the selected wind vector is not the closest ambiguity to the true wind. The current ambiguity selection routine for SeaWinds is ad hoc, but performs well under most circumstances. Factors such as instrument noise and rain can also cause the estimated wind flow to deviate from the true wind. A quality assurance (QA) analysis is performed to assess the ambiguity selection effectiveness and noise level of …

Iodat Analysis Content In Cooking Ingredients Using Iodometry And X-Ray Fluorescence Methods., Nelson Saksono

Makara Journal of Technology

Iodat Analysis Content in Cooking Ingredients Using Iodometry and X-ray Fluorescence Methods. Salt iodization program using iodine fortification into salt method is the best method that is effective and economical to overcome the problems caused by iodine deficiency. However in, its development there are some issues clamed that the use of iodized salt is ineffective since iodine content reduces, even disappear when the salt mix with other cooking ingredients. In order to investigated the existence of iodine in cooking ingredients, a research applying iodometry and X-ray fluorescence methods was carry out. The result obtained by iodometry method showed decreases in …

Emission Gas Reducer On Motor Vehicle, Automobile, Light Engine Of Boat And Stationary Combustion Engine., I Gusti Bagus Wijaya Kusuma

Makara Journal of Technology

Emission gas reducer on motor vehicle, automobile, light engine of boat and stationary combustion engine. The use of motor vehicle should be followed by protection against damages on the environment, since the exhaust gas from combustion engine has significantly affect on air and environmental pollution. One method to solve the problems in air pollution has been done by using a re-heater designed in Mechanical Engineering Department, University of Udayana. In accordance to the test on the re-heater, it can be seen very clear that the re-heater has significantly reduce the CO emission of about 54%. It also reduces the CO2 …