Digital Commons Network^™

Communication-Constrained Feedback Stability And Multi-Agent System Consensusability In Networked Control Systems, Laurentiu Dan Marinovici

LSU Doctoral Dissertations

With the advances in wireless communication, the topic of Networked Control Systems (NCSs) has become an interesting research subject. Moreover, the advantages they offer convinced companies to implement and use data networks for remote industrial control and process automation. Data networks prove to be very efficient for controlling distributed systems, which would otherwise require complex wiring connections on large or inaccessible areas. In addition, they are easier to maintain and more cost efficient. Unfortunately, stability and performance control is always going to be affected by network and communication issues, such as band-limited channels, quantization errors, sampling, delays, packet dropouts or …

Decoupling User Interface Design Using Libraries Of Reusable Components, Rajesh Sankaran

LSU Doctoral Dissertations

The integration of electronic and mechanical hardware, software and interaction design presents a challenging design space for researchers developing physical user interfaces and interactive artifacts. Currently in the academic research community, physical user interfaces and interactive artifacts are predominantly designed and prototyped either as one-off instances from the ground up, or using functionally rich hardware toolkits and prototyping systems. During this prototyping phase, undertaking an integral design of the interface or interactive artifact’s electronic hardware is frequently constraining due to the tight couplings between the different design realms and the typical need for iterations as the design matures. Several current …

Network Traffic Data Analysis, Harish Kapri

LSU Master's Theses

The desire to conceptualize network traffic in a prevailing communication network is a facet for many types of network research studies. In this research, real traffic traces collected over trans-Pacific backbone links (the MAWI repository, providing publicly available anonymized traces) are analyzed to study the underlying traffic patterns. All data analysis and visualization is carried out using Matlab (Matlab is a trademark of The Mathworks, Inc.). At packet level, we first measure parameters such as distribution of packet lengths, distribution of protocol types, and then fit following analytical models. Next, the concept of flow is introduced and flow based analysis …

Integrating Multiple Clusters For Compute-Intensive Applications, Zhifeng Yun

LSU Doctoral Dissertations

Multicluster grids provide one promising solution to satisfying the growing computational demands of compute-intensive applications. However, it is challenging to seamlessly integrate all participating clusters in different domains into a single virtual computational platform. In order to fully utilize the capabilities of multicluster grids, computer scientists need to deal with the issue of joining together participating autonomic systems practically and efficiently to execute grid-enabled applications. Driven by several compute-intensive applications, this theses develops a multicluster grid management toolkit called Pelecanus to bridge the gap between user's needs and the system's heterogeneity. Application scientists will be able to conduct very large-scale …

Server Assignment In Mirrored Server Environments, Shawn Farlow

LSU Master's Theses

Massively multiplayer online games (MMOGs) may use peer-to-peer, client-server, or mirrored-server environments. Since there exist multiple server options in mirrored server environments, a problem arises when deciding to which server each player should connect. We propose three distinct algorithms that assign players within Quality of Service (QoS) as each player joins and leaves, taking into consideration whether a player already in QoS can be moved to place a newly joining player in QoS without sacrificing QoS for the moved player. Our results show that for certain numbers of servers and values of QoS, our algorithms increase the total number of …

Efficient And Robust Signal Detection Algorithms For The Communication Applications, Lu Lu

LSU Doctoral Dissertations

Signal detection and estimation has been prevalent in signal processing and communications for many years. The relevant studies deal with the processing of information-bearing signals for the purpose of information extraction. Nevertheless, new robust and efficient signal detection and estimation techniques are still in demand since there emerge more and more practical applications which rely on them. In this dissertation work, we proposed several novel signal detection schemes for wireless communications applications, such as source localization algorithm, spectrum sensing method, and normality test. The associated theories and practice in robustness, computational complexity, and overall system performance evaluation are also provided.

Working Active Power, Reflected Active Power, And Detrimental Active Power In The Power System, Tracy Nakamura Toups

LSU Master's Theses

Study of decomposition of the active power into components with deeper economical meanings, namely working active power, reflected active power, and detrimental active power is the subject of the thesis. The decomposition of active power will be based on the Current’s Physical Component (CPC) Theory. Working active power is equivalent to useful power that is the rate of energy used to do work, such as mechanical power. Reflected active power is the rate of energy transfer that the load sends back to the supply which dissipates off the supply resistance. This reflected active power is not taken into account on …

A Study Of The Scale-Invariant Feature Transform On A Parallel Pipeline, Phaneendra Vinukonda

LSU Master's Theses

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In this thesis we study the running of the Scale Invariant Feature Transform (SIFT) algorithm on a pipelined computational platform. The SIFT algorithm is one of the most widely used methods for image feature extraction.

We develop a tile based template for running SIFT that facilitates the analysis while abstracting away lower-level details. We formalize the computational pipeline and the time to execute any algorithm on it based on the relative times taken by the pipeline stages. In the context of the SIFT algorithm, this reduces the time to that of running the entire image through a …

Surface Parameterization Over Regular Domains, Shenghua Wan

LSU Master's Theses

Surface parameterization has been widely studied and it has been playing a critical role in many geometric processing tasks in graphics, computer-aided design, visualization, vision, physical simulation and etc. Regular domains, such as polycubes, are favored due to their structural regularity and geometric simplicity. This thesis focuses on studying the surface parameterization over regular domains, i.e. polycubes, and develops effective computation algorithms. Firstly, the motivation for surface parameterization and polycube mapping is introduced. Secondly, we briefly review existing surface parameterization techniques, especially for extensively studied parameterization algorithms for topological disk surfaces and parameterizations over regular domains for closed surfaces. Then …

Lqg/Ltr Control Of Induction Motor, Girish Arvind Yajurvedi

LSU Master's Theses

Induction motors are the most rugged electrical equipment which are widely used in the industry. Owing to the non-linearity in its behaviour, it is not a trivial problem to solve and hence we are interested in using it as a control platform. Through several decades of research a wide number of control schemes have been developed for implementing the closed loop control. Based upon the merits and demerits of various schemes we choose a control scheme called the indirect vector control of Induction motor. Using the electrical dynamics of the motor model we design a LQG/LTR controller. We employ a …

Hydrodynamic Focusing Micropump Module With Pdms/Nickel-Particle Composite Diaphragms For Microfluidic Systems, Jeonghwan Kim

LSU Master's Theses

In this research, a rapid prototype of multi-fluidic speed-modulating (MFSM) micropump which enables modulation of hydrodynamic focusing in micro-fluidic flow has been designed, fabricated, and characterized. The size of the entire module is 33 mm x 25 mm x 8 mm and comprises of three MFSM micropumps to achieve hydrodynamic focusing. These pumps are simultaneously operated by the same actuation source. Each micropump consists of Tesla-type valves in the bottom layer and PDMS/Ni-particle composite (PNPC) diaphragm in the middle layer. The deflection of the diaphragm is obtained by the external pneumatic force, and the permanent magnet controls the displacement resulting …

Parameter Tuning And Experimental Results Of Power System Stabilizer, Bixiang Tang

LSU Master's Theses

Power system stabilizers (PSS) have been studied for many years as a method to increase power system stability. This thesis focuses on the tuning and structure of the power system stabilizer. Different types of power system stabilizers are reviewed. The one studied in this thesis is the integral of accelerated power stabilizer. The generator control system is introduced to illustrate the working environment of the PSS. The mathematic model of the generator, automatic voltage regulator and PSS are analyzed and the system transfer function in presence of the PSS is derived. Base on the transfer function, a new tuning method …

Implementation Of A Wireless Sensor Network With Ez430-Rf2500 Development Tools And Msp430fg4618/F2013 Experimenter Boards From Texas Instruments, Lu De Yang

LSU Master's Theses

Wireless sensor networks have found a great deal of applications in diverse areas. Recent interest has been focused on low-power feature of the sensor nodes because the power consumption is always an issue for wireless sensor nodes which are supplied from the batteries. The eZ430RF2500 Development Tool and MSP430FG4618/F2013 Experimenter Board from Texas Instruments have integrated MSP430 family of ultralow-power microcontrollers and CC2500 low-power wireless RF transceivers which are suitable for low-power, low-cost wireless applications. In this thesis, the features of these TI devices are explored and a wireless sensor network is implemented with these devices. To implement the routing …

Analyzing And Predicting Processor Vulnerability To Soft Errors Using Statistical Techniques, Lide Duan

LSU Doctoral Dissertations

The shrinking processor feature size, lower threshold voltage and increasing on-chip transistor density make current processors highly vulnerable to soft errors. Architectural Vulnerability Factor (AVF) reflects the probability that a raw soft error eventually causes a visible error in the program output, indicating the processor’s susceptibility to soft errors at architectural level. The awareness of the AVF, both at the early design stage and during program runtime, is greatly useful for designing reliable processors. However, measuring the AVF is extremely costly, resulting in large overheads in hardware, computation, and power. The situation is further exacerbated in a multi-threaded processor environment …

Blind Yield Detection In Steel Structure For Automatic Nondestructive Testing Using Ultrasonic Sensors, Hongting Zhang

LSU Master's Theses

Detection of yield zones using nondestructive testing (NDT) technology for assessing the structural integrity of the existing steel buildings/bridges is extremely important. The average energy over the “effective echoes” (in “good” signal quality) is a robust feature for the yield detection in steel structures. Nevertheless, this average-energy feature extraction requires rigorous manual data-acquisition and human operation. Therefore, in this thesis, we make the first-ever attempt to design a totally-blind and automatic steel-structure yielddetection mechanism, which requires neither the a priori information about the signal nor the human effort in calibration, operation, or data analysis. This new scheme is built upon …

Experimental Study Of Cognitive Radio Test-Bed Using Usrp, Venkat Vinod Patcha

LSU Master's Theses

Cognitive Radio is an emerging technology that enables efficient utilization of the spectrum. As such, it has created great interests in industrial and research fields. Many people have proposed test-bed models for the performance analysis of primary and secondary users in a real-time noise environment. However, these test-beds are generally lacking in their range of capabilities as well as accurate implementation of the proposed models. In this thesis, we develop our test-bed on USRP to achieve the spectrum sensing and co-existence of primary and secondary users, while implementing the rendezvous protocols for secondary traffic coordination. We first demonstrate the spectrum …

Power Management And Optimization, Hari Sundararajan

LSU Master's Theses

After many years of focusing on “faster” computers, people have started taking notice of the fact that the race for “speed” has had the unfortunate side effect of increasing the total power consumed, thereby increasing the total cost of ownership of these machines. The heat produced has required expensive cooling facilities. As a result, it is difficult to ignore the growing trend of “Green Computing,” which is defined by San Murugesan as “the study and practice of designing, manufacturing, using, and disposing of computers, servers, and associated subsystems – such as monitors, printers, storage devices, and networking and communication systems …

In-Wheel Motors: Express Comparative Method For Pmbl Motors, Pavani Gottipati

LSU Doctoral Dissertations

One of the challenges facing the electric vehicle industry today is the selection and design of a suitable in-wheel motor. Permanent Magnet Brushless (PMBL) motor is a good choice for the in-wheel motor because of its lossless excitation, improved efficiency, reduced weight and low maintenance. The PMBL motors can be further classified as Axial-Flux Twin-Rotor (AFTR) and Radial-Flux Twin-Rotor (RFTR) machines.

The objective of this dissertation is to develop a fast method for the selection of appropriate in-wheel motor depending on wheel size. To achieve this, torque equations are developed for a conventional single-rotor cylindrical, twin-rotor axial-flux and twin-rotor radial-flux …

Back-End Processing Of Scanning Mirrors With Scratch Drive Actuators, Pradeep Pai

LSU Master's Theses

The use of micro-electro-mechanical system (MEMS) processes in fabrication of micr- electro-mechanical devices for optical applications has been widespread. The invention of digital light processing (DLP) technology by Texas Instruments Inc. popularized the use of micro-mirrors. One of the applications of the micro-mirrors is in the form of scanners for biomedical imaging. The small size of mirrors and actuators makes them a good candidate for in vivo measurements/imaging. Various techniques in bulk- and surface-micromachining, and various actuators have been used to fabricate scanning mirrors. The scanning mirrors used in this work make use of scratch drive actuators (SDA) for their …

Development And Validation Of Biomechanical Models To Quantify Horse Back Forces At The Walk In Three Horse Breeds, Laxmi Raghunandana Kaidapuram

LSU Master's Theses

Therapeutic horseback riding is a common component of physical therapy programs. Quantification of the horse back forces will provide vital information to match therapeutic riders with equine partners. To meet this medical need, a model to quantify the horse back forces from ground reaction forces was developed to test the hypothesis that the forces transferred to a static weight on the horse’s back can be predicted given horse breed and weight. Simultaneous, real time kinetic, kinematic, and back force data on a static weight were collected from 7 adult horses: 3 thoroughbreds, 3 quarter horses, and 1 paso fino. An …

Performance Of Twin-Rotor Dc Homopolar Motor, Zhiwei Wang

LSU Master's Theses

A new concept of dual-rotor motor with counter-rotating propeller increases the efficiency of the ship propulsion used in marine industry. This concept can be realized by twin-rotor permanent magnet homopolar disc motor, which is the object of this thesis. The objectives of this thesis are to determine the motor electromechanical parameters applying a 3-D FEM modeling and to analyze the motor performance in steady-state and dynamic conditions. The objectives of this thesis are to determinate the PM DC homopolar twin-rotor disc motor electromechanical parameters by 3-D FEM modeling. Furthermore, the PM DC Homopolar perform determination in steady-state and dynamic conditions. …

Secure Distributed Detection In Bandwidth-Constrained Wireless Sensor Networks, Reza Soosahabi

LSU Master's Theses

Utilizing wireless sensor network (WSN) is a novel idea in a variety of applications. However, the limited resources allocated to the sensor nodes make the design of WSNs a challenging problem. We consider the problem of hypothesis testing in a bandwidth-constrained, low-power wireless sensor network operating over insecure links. Sensors quantize their observations and transmit their decisions to an intended (ally) fusion center (AFC) which combines the received messages to detect the state of an unknown hypothesis.

In many applications the sensor messages are vulnerable to unauthorized eavesdropping. The scarce bandwidth and processing power for the sensors rule out the …

Surface-Enhanced Raman Spectroscopy Substrates Based On Nanoporous Silicon And Pattern Transfer, Pallavi Rao Malempati

LSU Master's Theses

Surface-enhanced Raman scattering enhances the weak Raman scattering by using a roughened metal-coated surface as a catalyst. Roughness in the nanometer range provides the best enhancement. The nanostructures for the surface-enhanced Raman spectroscopy (SERS) substrates, in this work, are generated using an electrochemical etching process on silicon substrates. The patterns of nanoporous silicon thus generated are transferred onto transparent polydimethylsiloxane (PDMS) substrates using the “lift-off” process. An incomplex sputtering technique is employed to coat this substrate with a ~20 nm aluminum layer. Rhodamine 6G (R6G) molecules, when adsorbed to this metal surface, form the final SERS substrate that undergoes Raman …

Smart Access Control System With Behavioral Profiling And Dynamic Pin Concept, Lohit Penubaku

LSU Master's Theses

Since ancient time, an access control device has been used for securing valuable properties as well as lives from threatening peoples. The most representative security device is Lock/Key. Recently, those security device technologies have been improved tremendously and provided various types of security methods. Nevertheless, these methods are not individually perfect to provide optimal security so that in recent years many such methods have been combined and used together to provide the required level of security. However, such combination can enhance security for limited number of users only but very difficult to provide scalable security with the number of users …

Fault Detection In Process Control Plants Using Principal Component Analysis, Vamshi Krishna Kandula

LSU Master's Theses

The aim of this thesis is to use a statistical method (principal component analysis) to detect a fault in a system. PCA is a dimensionality reduction technique that is used here. First the PCA algorithm was implemented on a simple two dimensional random data to reduce its dimensionality. Then the algorithm was implemented on a three dimensional data from a linear first order process and introduce some white noise later on and compare the results with that under normal operating conditions, thus determining the presence of a fault. Then data from a real time plant is considered for testing. This …

Cost And Performance Modeling Of The Mu-Decoder, Raghavendra Kongari

LSU Master's Theses

In this thesis we study the implementation details of the MU-Decoders, a recently proposed hardware module that has been theoretically shown to be superior to other methods for generating subsets of large sets. Our study confirms this advantage. Specifically, we compare the performance of implementations of the LUT-Decoder (the most common configurable decoder) to the MU-Decoder. We show that for while the LUT-Decoder is slightly better than the MU-Decoder for arbitrary (and artificial) inputs, for a large class of inputs called totally ordered subsets, that have practical significance, the MU-Decoder is vastly superior in area to the LUT-Decoder. In terms …

Foldable Substrates For Micro-Ultrasonic Transducers, Karthik Balasubramanian

LSU Master's Theses

Ultrasound has broad range of applications from underwater examination, nondestructive testing of materials and medical diagnosis and treatment. The ultrasonic transducer plays an vital role in determining the resolution, sensitivity, as well as other diagnostic capabilities of an ultrasonic imaging system. Current piezoelectric transducer which dominates the medical field has limited applications compared to the capacitive ultrasonic transducer. The capacitive transducer is easy to fabricate compared to the piezoelectric transducer. In this work, the fabrication of a foldable substrate for a capacitive ultrasonic transducer has been discussed. The foldable substrate was fabricated using an ultrathin silicon wafer which is 50 …

Interpretation Of Power Phenomena In Three Phase Systems With Neutral Using Instantaneous Reactive Power P-Q Theory, Rahul Anil Kantharia

LSU Master's Theses

The Instantaneous Reactive power (IRP) p-q theory considered as a major power theory as well as a primary fundamental for switching compensator control in three-phase systems, is analyzed in order to verify its ability to describe and identify the power properties or power phenomena in a 3pN system with asymmetrical and non-sinusoidal voltages along with unbalanced loads. This analysis is an outcome of the misinterpretations of power phenomena in three-wire circuits shown by IRP p-q theory under non-sinusoidal conditions. Different load and supply conditions such as balanced, unbalanced and Harmonic generating loads along with asymmetrical and non-sinusoidal voltages are assumed …

Assymmetry In Distribution Systems: Causes, Harmful Effects And Remedies, Isaac Plummer

LSU Master's Theses

ABSTRACT: Current and voltage asymmetry denigrates the power system performance. The current asymmetry reduces efficiency, productivity and profits at the generation, transmission and distribution of electric energy. Voltage asymmetry reduces efficiency, productivity and profits at the consumption/utilization level. There are a lot of conference and journal papers on the subject of voltage and current asymmetry, however, the information is scattered over a large number of journals and conferences and published over several years. Therefore, the thesis provides a comprehensive compilation of all possible published information on current and voltage asymmetry in the electrical power systems. Published information on sources of …