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Design Of A Conditioner For Smoothing Wind Turbine Output Power, Murali Bottu, Mariesa Crow, A. Curt Elmore Sep 2010

Design Of A Conditioner For Smoothing Wind Turbine Output Power, Murali Bottu, Mariesa Crow, A. Curt Elmore

Electrical and Computer Engineering Faculty Research & Creative Works

As a result of wind speed intermittency, highly variable wind power output can adversely impact local loads. We propose a conditioner to smooth the variable wind power by utilizing the energy of an ultracapacitor. The conditioner is based on a single phase voltage source inverter (VSI) connected between the grid interconnection point and the ultracapacitor. The shunt VSI injects or absorbs active power from the line to smooth the wind power by utilizing the short term storage capabilities of the ultracapacitor. The ultracapacitor is connected to the DC link through a DC-DC converter, which maintains the voltage of the DC …

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Coated Steel Rebar For Enhanced Concrete-Steel Bond Strength And Corrosion Resistance, Genda Chen, Jeffery S. Volz, Richard K. Brow, Dongming Yan, Signo Tadeu Dos Reis, Chenglin Wu, Fujian Tang, Charles R. Werner, Xing Tao Sep 2010

Coated Steel Rebar For Enhanced Concrete-Steel Bond Strength And Corrosion Resistance, Genda Chen, Jeffery S. Volz, Richard K. Brow, Dongming Yan, Signo Tadeu Dos Reis, Chenglin Wu, Fujian Tang, Charles R. Werner, Xing Tao

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This report summarizes the findings and recommendations on the use of enamel coating in reinforced concrete structures both for bond strength and corrosion resistance of steel rebar. Extensive laboratory tests were conducted to characterize the properties of one- and two-layer enamel coatings. Pseudostatic tests were performed with pullout, beam and column specimens to characterize mechanical properties and develop design equations for the development length of steel rebar in lap splice and anchorage areas. The splice length equation was validated with the testing of large-scale columns under cyclic loading. For corrosion properties, ponding, salt spray, accelerated corrosion, potentiodynamic and electrochemical impedance …

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Missouri S&T Magazine Fall 2010, Missouri S&T Marketing And Communications Department, Miner Alumni Association Sep 2010

Missouri S&T Magazine Fall 2010, Missouri S&T Marketing And Communications Department, Miner Alumni Association

Missouri S&T Magazine

No abstract provided.

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The Use Of Spike-Based Representations For Hardware Audition Systems, Shih Chii Liu, Nima Mesgarani, John Harris, Hynek Hermansky Aug 2010

The Use Of Spike-Based Representations For Hardware Audition Systems, Shih Chii Liu, Nima Mesgarani, John Harris, Hynek Hermansky

Electrical and Computer Engineering Faculty Research & Creative Works

Humans are able to process speech and other sounds effectively in adverse environments, hearing through noise, reverberation, and interference from other speakers. To date, machines have been unable to match human performance. One profound difference between biological and engineering systems comes at the input stage. In machines, an acoustic signal is typically chopped into short equally spaced segments in time. In biological systems, the cochlea outputs asynchronous spikes that respond in real-time to acoustic inputs. In this paper we describe a spiking cochlea implementation and recent experiments in both speaker and speech recognition that use spikes as input. ©2010 IEEE.

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Mean Firing Rate Spike Representations For Speech Recognition, John G. Harris, Yukun Feng Aug 2010

Mean Firing Rate Spike Representations For Speech Recognition, John G. Harris, Yukun Feng

Electrical and Computer Engineering Faculty Research & Creative Works

The nature of spike coding of auditory signals is studied by comparing mean firing rate codes with conventional approaches in speech recognition tasks. Mean firing rate spike representations are problematic since most auditory nerve fibers are saturated at typical conversation levels. However, these problems are eased somewhat when it is considered that there are other nerve fibers (e.g. low spontaneous firing rate fibers) that could efficiently encode the information at each channel of the cochlea. We show that window-based, mean firing rate features can be used with a crude cochlea model to achieve the same level of performance as a …

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An Adaptive Neuron Circuit For Signal Compression, Sheng Feng Yen, John G. Harris Aug 2010

An Adaptive Neuron Circuit For Signal Compression, Sheng Feng Yen, John G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

We present a low-bandwidth analog circuit for implementing an adaptive biphasic leaky integrate-and-fire neuron. This neuron circuit is targeted for signal compression in neural recording applications. Unlike other adaptive neuron circuits, this adaptive integrate-and-fire neuron supports signal reconstruction with known threshold voltages. Matlab simulations show promising bandwidth reduction comparing to an integrate-and-fire neuron without the adaptive feature. We quantify the circuit performance in terms of the tradeoff between signal reconstruction accuracy and bandwidth. ©2010 IEEE.

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Improved Pcr Design For Mouse Dna By Training Finite State Machines, Salik R. Yadav, Steven M. Corns Aug 2010

Improved Pcr Design For Mouse Dna By Training Finite State Machines, Salik R. Yadav, Steven M. Corns

Engineering Management and Systems Engineering Faculty Research & Creative Works

This project presents an updated method for classification of polymerase chain reaction primers in mice using finite state classifiers. This is done to compensate for many lab, organism and chemical specific factors that are costly. using Finite State Classifiers can help decrease the number of primers that fail to amplify correctly. for training these classifiers, five different evolutionary algorithms that use an incremental fitness reward are used. Variations to the number of generations and the values in the fitness reward are examined, and the resulting designs are presented. by controlling the fitness reward correctly, there is a potential to develop …

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Partial And Spectral-Viscosity Models For Geophysical Flows, Qingshan Chen, Max Gunzburger, Xiaoming Wang Aug 2010

Partial And Spectral-Viscosity Models For Geophysical Flows, Qingshan Chen, Max Gunzburger, Xiaoming Wang

Mathematics and Statistics Faculty Research & Creative Works

Two models based on the hydrostatic primitive equations are proposed. the first model is the primitive equations with partial viscosity only and is oriented towards large-scale wave structures in the ocean and atmosphere. the second model is the viscous primitive equations with spectral eddy viscosity and is oriented towards turbulent geophysical flows. for both models, the existence and uniqueness of global strong solutions are established. for the second model, the convergence of the solutions to the solutions of the classical primitive equations as eddy viscosity parameters tend to zero is also established. © 2010 Editorial Office of CAM (Fudan University) …

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Examples Of Boundary Layers Associated With The Incompressible Navier-Stokes Equations, Xiaoming Wang Aug 2010

Examples Of Boundary Layers Associated With The Incompressible Navier-Stokes Equations, Xiaoming Wang

Mathematics and Statistics Faculty Research & Creative Works

The author surveys a few examples of boundary layers for which the Prandtl boundary layer theory can be rigorously validated. All of them are associated with the incompressible Navier-Stokes equations for Newtonian fluids equipped with various Dirichlet boundary conditions (specified velocity). These examples include a family of (nonlinear 3D) plane parallel flows, a family of (nonlinear) parallel pipe flows, as well as flows with uniform injection and suction at the boundary. We also identify a key ingredient in establishing the validity of the Prandtl type theory, i.e., a spectral constraint on the approximate solution to the Navier-Stokes system constructed by …

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Layered Frequency-Domain Turbo Equalization For Single Carrier Broadband Mimo Systems, Jian Zhang, Yahong Rosa Zheng, Jingxian Wu Aug 2010

Layered Frequency-Domain Turbo Equalization For Single Carrier Broadband Mimo Systems, Jian Zhang, Yahong Rosa Zheng, Jingxian Wu

Electrical and Computer Engineering Faculty Research & Creative Works

A new layered frequency-domain turbo equalization (LFDTE) scheme is proposed for single carrier (SC) multiple input multiple-output (MIMO) systems. the proposed scheme combines the respective advantages of layered detection and turbo equalization to further lower the bit error rate (BER) for high-data-rate communications. Different from the traditional frequency-domain turbo equalization (FDTE) method for MIMO systems, our new detection algorithm employs a layered structure in each turbo iteration, and at each layer a group of best data streams is detected in the form of soft symbols and then canceled from the received signals in frequency domain. the extrinsic information for the …

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Opportunistic Relaying For Multi-Antenna Cooperative Decode-And-Forward Relay Networks, Weiliang Zeng, Chengshan Xiao, Youzheng Wang, Jianhua Lu Aug 2010

Opportunistic Relaying For Multi-Antenna Cooperative Decode-And-Forward Relay Networks, Weiliang Zeng, Chengshan Xiao, Youzheng Wang, Jianhua Lu

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, we investigate the relaying scheme for multi-antenna cooperative networks without channel state information at the transmitters. It is shown that the classic opportunistic relaying scheme, which allows only one relay node to forward the message, may lead to significant loss when it is extended to the corresponding multi-antenna relay scenarios. a generalized opportunistic relaying approach, which selects more transmit antennas distributed on multiple relay nodes to transmit data simultaneously, is proposed to maximize the network throughput via balancing the source-relay and the relay-destination channels. Numerical examples show the large impact of multiple antennas and relays on the …

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Low-Complexity Turbo Block Decision Feedback Equalization For Mimo Systems, Jun Tao, Jingxian Wu, Yahong Rosa Zheng Aug 2010

Low-Complexity Turbo Block Decision Feedback Equalization For Mimo Systems, Jun Tao, Jingxian Wu, Yahong Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a low-complexity turbo block decision feedback equalizer (BDFE) with reliability-Based successive soft interference cancellation (SSIC) for multiple-input multiple-output (MIMO) systems. Turbo equalization in MIMO systems needs to combat both InterSymbol interference (ISI) due to frequency-selective fading and multiplexing interference (MI) among data streams transmitted by different antennas. the proposed MIMO BDFE performs SSIC on both ISI in the time domain and MI in the space domain. for an SSIC receiver, the order in which the symbols are detected and canceled is critical to the system performance, yet it is often overlooked in the literature. We propose a …

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Solving Multi-Scale Low Frequency Electromagnetic Problems, Zhi Guo Qian, Mao Kun Li, Zu Hui Ma, Li (Lijun) Jun Jiang, Weng Cho Chew Aug 2010

Solving Multi-Scale Low Frequency Electromagnetic Problems, Zhi Guo Qian, Mao Kun Li, Zu Hui Ma, Li (Lijun) Jun Jiang, Weng Cho Chew

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, we will discuss two methods to tackle the low-frequency, multi-scale electromagnetics problem. First we will discuss the augmented electric field integral equation (AEFIE), and then, we will discuss the equivalence principle algorithm (EPA). The AEFIE allows the solution of such problems without the need to perform a loop search of a complex structure. The EPA allows the separation of circuit physics from wave physics in a multiscale problem. Hybridization of these two methods will be discussed.

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Mea Manufacturing Using An Additive Manufacturing Process To Deposit A Catalyst Pattern In An Mea And Its Impact On Cost Reduction, Nikhil P. Kulkarni, Todd E. Sparks, Gargi Tandra, Frank W. Liou Aug 2010

Mea Manufacturing Using An Additive Manufacturing Process To Deposit A Catalyst Pattern In An Mea And Its Impact On Cost Reduction, Nikhil P. Kulkarni, Todd E. Sparks, Gargi Tandra, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The manufacturing of a fuel cell Membrane Electrode Assembly (MEA) is a significant cost driver in polymer-electrolyte membrane (PEM) fuel cell technologies, primarily due to the inclusion of expensive materials in the catalyst layer. The selective deposition of a catalyst on the MEA of a fuel cell can drastically reduce the costs depending upon the catalyst, method used for deposition, and production volume. In this paper, testing and analysis of a novel catalyst iridium oxide is discussed. The performance of the catalyst will be compared with the conventional catalysts which will give us an estimate of its effectiveness however, in …

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Selective Laser Sintering And Freeze Extrusion Fabrication Of Scaffolds For Bone Repair Using 13-93 Bioactive Glass: A Comparison, Krishna C. R. Kolan, Nikhil P. Doiphode, Ming-Chuan Leu Aug 2010

Selective Laser Sintering And Freeze Extrusion Fabrication Of Scaffolds For Bone Repair Using 13-93 Bioactive Glass: A Comparison, Krishna C. R. Kolan, Nikhil P. Doiphode, Ming-Chuan Leu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

13-93 glass is a third-generation bioactive material which accelerates the bone’s natural ability to heal by itself through bonding with surrounding tissues. It is an important requirement for synthetic scaffolds to maintain their bioactivity and mechanical strength with a porous internal architecture comparable to that of a human bone. Additive manufacturing technologies provide a better control over design and fabrication of porous structures than conventional methods. In this paper, we discuss and compare some of the common aspects in the scaffold fabrication using two such processes, viz. selective laser sintering (SLS) and freeze extrusion fabrication (FEF). Scaffolds fabricated using each …

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Selective Laser Sintering Of 13-93 Bioactive Glass, Krishna C. R. Kolan, Ming-Chuan Leu, Greg Hilmas, Mariano Garcia Velez Aug 2010

Selective Laser Sintering Of 13-93 Bioactive Glass, Krishna C. R. Kolan, Ming-Chuan Leu, Greg Hilmas, Mariano Garcia Velez

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Bioactive glasses are more promising than biopolymers in fabricating scaffolds for bone tissue repair because they convert to hydroxyapatite, when implanted in vivo. Both direct and indirect selective laser sintering (SLS) methods of 13-93 bioactive glass were considered in this research to study the feasibility of fabricating scaffolds for bone repair applications. Stearic acid was used as the binder in the indirect method to fabricate the scaffolds. The green scaffolds underwent binder burnout and sintering at various soaking conditions between 675⁰C and 700⁰C, achieving a maximum compressive strength of 23.6 MPa, which is higher than that of the human cancellous …

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Effect Of Different Graphite Materials On Electrical Conductivity And Flexural Strength Of Bipolar Plates Fabricated By Selective Laser Sintering, Nannan Guo, Ming-Chuan Leu Aug 2010

Effect Of Different Graphite Materials On Electrical Conductivity And Flexural Strength Of Bipolar Plates Fabricated By Selective Laser Sintering, Nannan Guo, Ming-Chuan Leu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Graphite is an excellent material for bipolar plates used in Proton Exchange Membrane (PEM) fuel cell due to its great chemical resistance, but the brittle nature makes it difficult to manufacture. Selective Laser Sintering (SLS) based on layer-by-layer manufacturing technology can fabricate graphite bipolar plates with complex gas flow channels. To improve the performance of bipolar plates including electrical conductivity and flexural strength, different graphite materials (natural graphite, synthetic graphite, carbon black, and carbon fiber) were investigated to fabricate test samples. These samples then went through post processing including carbonization and infiltration. The results show that bipolar plates with electrical …

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Laser Based Rapid Manufacturing Of Metallic Gas Diffusion Layers For Pem Fuel Cells, Gargi Tandra, Todd E. Sparks, Shyam Barua, Nikhil P. Kulkarni, Frank W. Liou Aug 2010

Laser Based Rapid Manufacturing Of Metallic Gas Diffusion Layers For Pem Fuel Cells, Gargi Tandra, Todd E. Sparks, Shyam Barua, Nikhil P. Kulkarni, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Gas Diffusion layers (GDL’s) are an essential component of Polymer Electrolyte Membrane Fuel cells (PEMFC’s) which aid in thermal & electrical conductivities, water management and act as backup layers for the membrane electrode assemblies. This paper summarizes the effort to prototype metallic GDL designs using a miniature laser deposition system developed at Missouri University of Science & Technology. The pore sizes are controlled by masking the diverging laser beam using stainless steel masks of varying sizes and shapes. The through pore feature and further treatment of the GDL’s for hydrophobicity reduces the water management issue and thereby increases the performance …

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Development Of A Low Cost Imaging System For A Laser Metal Deposition Process, Shyam Barua, Todd E. Sparks, Frank W. Liou Aug 2010

Development Of A Low Cost Imaging System For A Laser Metal Deposition Process, Shyam Barua, Todd E. Sparks, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The size of the melt pool created by the laser is one of the most important quality characteristic in a laser metal deposition process. This paper discusses the development of a low-cost vision system to automatically determine the size of the melt pool for in-process control. To cope with the intense infrared signal from the laser and melt pool, external ultraviolet illumination is paired with narrow bandpass filters on a usb microscope to achieve a clear image of the melt pool. The sensitivity of the melt pool to changes in system parameters and various substrate materials are also evaluated.

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Multi-Axis Planning System (Maps) For Hybrid Laser Metal Deposition Processes, Frank W. Liou, Jianzhong Ruan, Todd E. Sparks Aug 2010

Multi-Axis Planning System (Maps) For Hybrid Laser Metal Deposition Processes, Frank W. Liou, Jianzhong Ruan, Todd E. Sparks

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper summarizes the research and development of a Multi-Axis Planning System (MAPS) for hybrid laser metal deposition processes. The project goal is to enable the current direct metal deposition systems to fully control and utilize multi-axis capability to make complex parts. MAPS allows fully automated process planning for multi-axis layered manufacturing to control direct metal deposition machines for automated fabrication. Such a capability will lead to dramatic reductions in lead time and manufacturing costs for high-value, low-volume components with high performance material. The overall approach, slicing algorithm, machine simulation for planning validation, and the planning results will be presented.

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Freeze Extrusion Fabrication Of 13-93 Bioactive Glass Scaffolds For Bone Repair, Tieshu Huang, Nikhil D. Doiphode, M. N. Rahaman, Ming-Chuan Leu, B. Sonny Bal, D. E. Day Aug 2010

Freeze Extrusion Fabrication Of 13-93 Bioactive Glass Scaffolds For Bone Repair, Tieshu Huang, Nikhil D. Doiphode, M. N. Rahaman, Ming-Chuan Leu, B. Sonny Bal, D. E. Day

Materials Science and Engineering Faculty Research & Creative Works

There is an increasing demand for synthetic scaffolds with the requisite biocompatibility, internal architecture, and mechanical properties for the bone repair and regeneration. In this work, scaffolds of a silicate bioactive glass (13-93) were prepared by a freeze extrusion fabrication (FEF) method and evaluated in vitro for potential applications in bone repair and regeneration. The process parameters for FEF production of scaffolds with the requisite microstructural characteristics, as well as the mechanical and cell culture response of the scaffolds were evaluated. After binder burnout and sintering (60 min at 700°C), the scaffolds consisted of a dense glass network with interpenetrating …

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Uncertainty Analysis In Laser Deposition Finish Machining Operations, Jomy Francis, Todd E. Sparks, Frank W. Liou Aug 2010

Uncertainty Analysis In Laser Deposition Finish Machining Operations, Jomy Francis, Todd E. Sparks, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The Laser Aided Manufacturing Process (LAMP) from Missouri S&T is a laser based metals rapid manufacturing process that uses machining to improve the final part's surface finish. When free-form machining, the absence of enough deposited material results in inconsistent scallop heights which result in poor surface finish or incorrect geometry in the final part. This paper investigates a probabilistic approach to various uncertainties involved in the deposition and subsequent machining of an arbitrary part. Furthermore, this paper analyses the machine errors which makes the response of Scallop Height to exceed the predefined maximum scallop height when traveling along the tool …

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Computer Aided Contour Profiling Of High Strength Deposits, Sriram Praneeth Isanaka, Amar Bala Sridhar, Frank W. Liou, Joseph William Newkirk Aug 2010

Computer Aided Contour Profiling Of High Strength Deposits, Sriram Praneeth Isanaka, Amar Bala Sridhar, Frank W. Liou, Joseph William Newkirk

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Additive manufacturing processes suffer from the effect of ripples, edge rounding and surface variations. To reduce their effect, ideal process parameters for the laser deposition process were investigated. Also, a new method was identified to analyze deposits by accurately plotting their contours. This was achieved through point cloud data of the deposits generated using coordinate measurement and 3D scanning. Curve fitting was performed on the data in Matlab to generate the contours of the deposit. The intercept values, heights, and contact angle of the curves give an indication of the uniformity of deposits and aid in reducing defects.

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Optimization Of Selective Laser Sintering Process For Fabrication Of Zirconium Diboride Parts, Ming-Chuan Leu, Shashwatashish Pattnaik, Greg Hilmas Aug 2010

Optimization Of Selective Laser Sintering Process For Fabrication Of Zirconium Diboride Parts, Ming-Chuan Leu, Shashwatashish Pattnaik, Greg Hilmas

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Selective Laser Sintering (SLS) was investigated to fabricate Zirconium Diboride (ZrB2) parts for ultra-high temperature applications. Experiments were conducted to determine values of SLS process parameters (laser power, scan speed, line spacing, and layer thickness) that can be used to build ZrB2 parts with high integrity and sharp geometrical features. A sacrificial plate with a proper number of layers (determined from experimentation) separated from the main part was built in order to reduce thermal gradients when building the main part. The sacrificial plate was found to assist in eliminating cracks in the bottom of the main part. …

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Channel Equalization For Single Carrier Mimo Underwater Acoustic Communications, Chengshan Xiao, Jun Tao, Yahong Rosa Zheng, T. C. Yang, Wen Bin Yang Aug 2010

Channel Equalization For Single Carrier Mimo Underwater Acoustic Communications, Chengshan Xiao, Jun Tao, Yahong Rosa Zheng, T. C. Yang, Wen Bin Yang

Electrical and Computer Engineering Faculty Research & Creative Works

Multiple-input multiple-output (MIMO) underwater acoustic (UWA) channels introduce both space-time interference (STI) and time-varying phase distortion for transmitted signals. in such cases, the equalized symbols produced by conventional equalizer aiming for STI cancelation suffer phase rotation and thus cannot be reliably detected. in this paper, we propose a new equalization scheme for high data rate single carrier MIMO UWA channels. Different from existing methods employing joint equalization and symbol wise phase tracking technology, the proposed scheme decouples the interference cancelation (IC) operation and the phase compensation operation, leading to a generalized equalizer structure combining an IC equalizer with a phase …

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Aspergillus Fumigatus Sida Is A Highly Specific Ornithine Hydroxylase With Bound Flavin Cofactor, Samuel W. Chocklett, Pablo Sobrado Aug 2010

Aspergillus Fumigatus Sida Is A Highly Specific Ornithine Hydroxylase With Bound Flavin Cofactor, Samuel W. Chocklett, Pablo Sobrado

Chemistry Faculty Research & Creative Works

Ferrichrome is a hydroxamate-containing siderophore produced by the pathogenic fungus Aspergillus fumigatus under iron-limiting conditions. This siderophore contains N5-hydroxylated l-ornithines essential for iron binding. A. fumigatus siderophore A (Af SidA) catalyzes the flavin- and NADPH-dependent hydroxylation of l-ornithine in ferrichrome biosynthesis. Af SidA was recombinantly expressed and purified as a soluble tetramer and is the first member of this class of flavin monooxygenases to be isolated with a bound flavin cofactor. The enzyme showed typical saturation kinetics with respect to l-ornithine while substrate inhibition was observed at high concentrations of NADPH and NADH. Increasing amounts of hydrogen peroxide were measured …

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Performance Analysis Of Secure Hierarchical Data Aggregation In Wireless Sensor Networks, Vimal Kumar, Sanjay Madria Aug 2010

Performance Analysis Of Secure Hierarchical Data Aggregation In Wireless Sensor Networks, Vimal Kumar, Sanjay Madria

Computer Science Faculty Research & Creative Works

Data aggregation is a technique used to conserve battery power in wireless sensor networks (WSN). While providing security in such a scenario it is also important that we minimize the number of security operations as they are computationally expensive, without compromising on the security. in this paper we evaluate the performance of such an end-to-end security algorithm. We provide our results from the implementation of the algorithm on mica2 motes and conclude how it is better than traditional hop by hop security. © 2010 IEEE.

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A Communication Efficient Framework For Finding Outliers In Wireless Sensor Networks, Dylan Mcdonald, Stewart Sanchez, Sanjay Kumar Madria, Fikret Ercal Aug 2010

A Communication Efficient Framework For Finding Outliers In Wireless Sensor Networks, Dylan Mcdonald, Stewart Sanchez, Sanjay Kumar Madria, Fikret Ercal

Computer Science Faculty Research & Creative Works

Outlier detection is a well-studied problem in various fields. the unique challenges of wireless sensor networks make this problem especially challenging. Sensors can detect outliers for a plethora of reasons and these reasons need to be inferred in real time. Here, we present a new communication technique to find outliers in a wireless sensor network. Communication is minimized through controlling sensor when sensors are allowed to communicate. at the same time, minimal assumptions are made about the nature of the data set as to minimize the loss of generality in the architecture. © 2010 IEEE.

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Efficient Simulation Architecture For Routing And Replication In Mobile Peer To Peer Network Of Uavs, Hemanth Meka, Sanjay Kumar Madria, Mohan Kumar, Mark Linderman, Sharma Chakravarthy Aug 2010

Efficient Simulation Architecture For Routing And Replication In Mobile Peer To Peer Network Of Uavs, Hemanth Meka, Sanjay Kumar Madria, Mohan Kumar, Mark Linderman, Sharma Chakravarthy

Computer Science Faculty Research & Creative Works

Most of the routing and replication algorithms assume the network to be large and therefore, the architecture and algorithms are designed to be scalable. These algorithms however may not perform well with limited number of nodes in a network of UAVs. It is better to design and simulate such algorithms to increase the efficiency in a small network as scalability is no longer an issue. for such networks, we present design and simulation of some effective routing and replication algorithms to route packets, disseminate information, and replicate data among nodes. © 2010 IEEE.

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Real-Time Data Compression In Wireless Sensor Networks, Tommy Szalapski, Sanjay Madria Aug 2010

Real-Time Data Compression In Wireless Sensor Networks, Tommy Szalapski, Sanjay Madria

Computer Science Faculty Research & Creative Works

Wireless sensor networks possess significant limitations in storage, bandwidth, and power. Additionally, real-time sensor networks cannot tolerate high latency. While some good compression algorithms exist specific to sensor networks, there remains a need for methods that do not introduce additional latency. This paper introduces a compression scheme which reduces storage, bandwidth, and power while also minimizing latency. Our Huffman style compression scheme exploits temporal locality and delta compression to provide better bandwidth utilization, thus reducing latency for real time applications. © 2010 IEEE.

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