Computer Sciences Commons^™

Splai: Computational Finite Element Model For Sensor Networks, Ruzana Ishak, Shadaruddin Salleh, Stephan Olariu, Mohd.Ismail Abdul Aziz

Computer Science Faculty Publications

Wireless sensor network refers to a group of sensors, linked by a wireless medium to perform distributed sensing task. The primary interest is their capability in monitoring the physical environment through the deployment of numerous tiny, intelligent, wireless networked sensor nodes. Our interest consists of a sensor network, which includes a few specialized nodes called processing elements that can perform some limited computational capabilities. In this paper, we propose a model called SPLAI that allows the network to compute a finite element problem where the processing elements are modeled as the nodes in the linear triangular approximation problem. Our model …

Synchronization And Multiple Group Server Support For Kepler, K. Maly, M. Zubair, H. Siripuram, S. Zunjarwad, Yannis Manolopoulos (Ed.), Joaquim Filipe (Ed.), Panos Constantopoulos (Ed.), José Cordeiro (Ed.)

Computer Science Faculty Publications

In the last decade literally thousands of digital libraries have emerged but one of the biggest obstacles for dissemination of information to a user community is that many digital libraries use different, proprietary technologies that inhibit interoperability. Kepler framework addresses interoperability and gives publication control to individual publishers. In Kepler, OAI-PMH is used to support "personal data providers" or "archivelets".". In our vision, individual publishers can be integrated with an institutional repository like Dspace by means of a Kepler Group Digital Library (GDL). The GDL aggregates metadata and full text from archivelets and can act as an OAI-compliant data provider …

A Dyadic Composition To Foster Virtual Team Effectiveness: An Experimental Study, Gamze Karayaz

Engineering Management & Systems Engineering Theses & Dissertations

The importance of effectiveness for virtual teamwork continues to gain momentum as technology and globalization of work accelerate. The implementation of virtual teams provides one approach to enhance competitiveness, overcoming the disadvantages of space and time differences through collaborative technologies. The influence of structure to virtual team performance has not been clearly established in the literature. The purpose of this research study was to investigate the effectiveness of a dyad structured approach for virtual teams using a quasi-experimental research design.

This research investigated four questions related to the influence of structure on virtual team effectiveness related to task performance, communication …

Group Key Management In Wireless Ad-Hoc And Sensor Networks, Mohammed A. Moharrum

Computer Science Theses & Dissertations

A growing number of secure group applications in both civilian and military domains is being deployed in WAHNs. A Wireless Ad-hoc Network (WARN) is a collection of autonomous nodes or terminals that communicate with each other by forming a multi-hop radio network and maintaining connectivity in a decentralized manner. A Mobile Ad-hoc Network (MANET) is a special type of WARN with mobile users. MANET nodes have limited communication, computational capabilities, and power. Wireless Sensor Networks (WSNs) are sensor networks with massive numbers of small, inexpensive devices pervasive throughout electrical and mechanical systems and ubiquitous throughout the environment that monitor and …

Radar - A Novel Admission Control And Handoff Management Scheme For Multimedia Leo Satellite Networks, Syed Rashidali Rizvi

Computer Science Theses & Dissertations

Low Earth Orbit (LEO) satellite networks are deployed as an enhancement to terrestrial wireless networks in order to provide broadband services to users regardless of their location. In addition to global coverage, these satellite systems support communications with hand-held devices and offer low cost-per-minute access cost, making them promising platforms for Personal Communication Services (PCS). LEO satellites are expected to support multimedia traffic and to provide their users with some form of Quality of Service (QoS) guarantees. However, the limited bandwidth of the satellite channel, satellite rotation around the Earth and mobility of end-users makes QoS provisioning and mobility management …

Robust And Efficient Localization Techniques For Cellular And Wireless Sensor Networks, Haseebulla M. Khan

Computer Science Theses & Dissertations

Localization in wireless networks refers to a collection of tasks that, collectively, determines the location of a mobile user, striving to hide the effects of mobility from the user and/or application. Localization has become an important issue and has drawn considerable attention, as many applications including E-911, cargo tracking, locating patients, location-sensitive billing, etc., require knowledge of the location of user/objects. It was realized, quite a while back, that extending emergency 911-like services (E-911) to continually growing mobile population is one of the extremely important localization applications. The bulk of the proposed solutions to emergency location management in wireless environments …

Dream: A Theoretical Analysis, Xueying Qi

Computer Science Theses & Dissertations

A Mobile Ad-hoc Network (MANET, for short) is a collection of mobile nodes deployed in support of a short-lived special-purpose operation. Examples include search-and-rescue missions, law-enforcement, multimedia classrooms, and among many others. Unlike cellular or satellite networks, MANET do not rely on any form of pre-existing infrastructure. The mobility of nodes combined with the lack of infrastructure makes routing in MANET notoriously difficult. It was recently suggested that routing in MANET can use to advantage geographic information that the nodes may acquire either by endowing them with a GPS chip or simply by using known localization algorithms. Distance Routing Effect …

Non-Linear And Linear Transformations Of Features For Robust Speech Recognition And Speaker Identification, Saurabh Prasad

Electrical & Computer Engineering Theses & Dissertations

Automatic speech recognizers perform poorly when training and test data are systematically different in terms of noise and channel characteristics. One manifestation of such differences is variations in the probability density functions (pdfs) between training and test features. Consequently, both automatic speech recognition and automatic speaker identification may be severely degraded. Previous attempts to mm1m1ze this problem include Cepstral Mean and Variance Normalization and transforming all speech features to a uni-variate Gaussian pdf. In this thesis, two techniques are presented for non-linearly scaling speech features to fit them to a target pdf - the first is based on the principles …

Fine-Tuning Of Mass-Spring Model Properties For Simulating Realistic Soft Body Deformation, Sylva A. Girtelschmid

Computational Modeling & Simulation Engineering Theses & Dissertations

Obtaining a well behaved soft-tissue model is one of the most challenging and important tasks in the development of surgical simulation systems. Achieving both accurate and real-time deformation response from a soft-tissue model becomes more difficult as the complexity of the represented anatomy and the degree of deformation increases. One common approach to modeling deformable objects is the Mass-Spring (MS) system method. Mass-Spring systems are attractive to real-time applications due to their relatively low computational requirement and ease of implementation. However, their parameter determination is typically done manually, which becomes tedious when accurate approximation to real-world objects is desired. This …

Mobility-Pattern Based Localization Update Algorithm For Mobile Wireless Sensor Networks, Mohammad Yacoub Al-Laho

Electrical & Computer Engineering Theses & Dissertations

In mobile wireless sensor networks, sensors move in the monitored area at any direction and speed. Unlike many other networking hosts, sensor nodes do not have global addresses. They are often identified by using a location-based addressing scheme. Therefore, it is important to have the knowledge of the sensor location indicating where the data came from. In this thesis, three localization update algorithms were designed, Specifically, a sensor movement is divided into three states: Pause, Linear, and Random. Each state adopts different localization update algorithm. Since complex movement involves different mobility patterns, a state transition model is developed to …

A Feature Specific Modular Approach For Pose And Illumination Invariant Face Recognition, Praveen Sankaran

Electrical & Computer Engineering Theses & Dissertations

A feature specific modular-PCA (Principal Component Analysis) approach on face images in multiple views for pose and illumination invariant face recognition is presented in this thesis. Principal components are extracted from different sub-modules of the image and are concatenated to make a single signature vector to represent a face region in a particular viewing angle. Additional principal components are extracted horn image regions representing key facial feature and are added as an extension of the signature vector. Feature specific modular-PCA approach is capable of recognizing faces in varying illumination conditions and facial expressions as the modular components represent the local …

Strategies For Analysis Of Unimodal And Multimodal Data For Simulation, Anshul Rai Sharma

Electrical & Computer Engineering Theses & Dissertations

The primary objective of this thesis is to provide strategies for analysis for data associated with simulation. Data analysis is an important part of the simulation process. Typically more stress is laid upon the development of the computer simulation while the data analysis takes a back seat. However, the accuracy of a simulation depends on the data driving it. In other words, any simulation is only as accurate as the input data fed into the simulation. Also, the output of simulation should be analyzed properly in order to validly estimate the performance of the system being simulated. The focus of …

Opal: In Vivo Based Preservation Framework For Locating Lost Web Pages, Terry L. Harrison

Computer Science Theses & Dissertations

We present Opal, a framework for interactively locating missing web pages (http status code 404). Opal is an example of "in vivo" preservation: harnessing the collective behavior of web archives, commercial search engines, and research projects for the purpose of preservation. Opal servers learn from their experiences and are able to share their knowledge with other Opal servers using the Open Archives Initiative Protocol for Metadata Harvesting (OAI-PMH). Using cached copies that can be found on the web, Opal creates lexical signatures which are then used to search for similar versions of the web page. Using the OAI-PMH to facilitate …

Collaborative Caching For Efficient And Robust Certificate Authority Services In Mobile Ad-Hoc Networks, Laith Abdulaziz Al-Sulaiman

Computer Science Theses & Dissertations

Security in Mobile Ad-Hoc Network (MANET) is getting a lot of attention due to its inherent vulnerability to a wide spectrum of attacks. Threats exist in every layer of MANET stack, and different solutions have been adapted for each security problem. Additionally, availability is an important criterion in most MANET solutions, but many security frameworks did not consider it. Public-Key Infrastructure (PKI) is no exception, and its deployment in MANET needs major design and implementation modifications that can fit constraints unique to this environment. Our focus in this dissertation is to adapt and increase the availability of Certificate Authority (CA) …

Programmable Process Flow Networks, Filip D. Cuckov

Electrical & Computer Engineering Theses & Dissertations

A model that introduces programmability to processes occurring in a cargo terminal simulation through the use of a process language is presented in this thesis. The model provides a means for a straight-forward definition, and redefinition of changing processes, their incorporation in the simulation architecture and efficient execution. The model was built to investigate a solution for transforming the cargo terminal simulation CPortS into a process-oriented simulation without hard-coded processes. The approach taken separates the system into an architecture and a set of processes which utilize and interact with the architecture's resources and infrastructure. The processes that take place within …

Creating Software [Sic] Environments On An M-Node Beowulf Cluster To Execute Discrete-Event Simulations, Jermaine Fitz-Gerald Headley

Electrical & Computer Engineering Theses & Dissertations

This thesis describes the development of a software tool that facilitates the creation of software environments that make a simulation tool execute k replications of an application program on several nodes of an M-node Beowulf cluster. It is assumed that each cluster-node consists of p processors. The p processors that are contained in the master cluster-node are termed master processors, and the p processors that are contained in a slave cluster-node are termed slave processors. The slave processors are used to execute the replications, while the master processors are dedicated to schedule the replications and process other housekeeping chores. For …

Rapid Prototyping For The Design Of Virtual Worlds, Prabhu V. Krishnan

Electrical & Computer Engineering Theses & Dissertations

Development of Virtual Reality (VR) applications is challenging where application developers are required to have expertise in the target VR technologies along with the problem domain expertise. New VR technologies impose a significant learning curve to even the most experienced VR developer. The proposed solution relies on synthesis to automate the migration of a VR application to a new unfamiliar VR platform/technology. To solve the problem, the Common Scene Definition Framework (CSDF) was developed, that serves as a superset/model representation of the target virtual world. Input modules were developed to populate the framework with the capabilities of the virtual world …

Generalization Issues In Pattern Classification Applied To Speaker Identification, Mame C. Sall

Electrical & Computer Engineering Theses & Dissertations

This thesis is an extension of previous work on speaker identification, but with a primary focus on the generalization performance of patterns classifiers for speaker identification. The goal for all pattern classifiers is to generalize to new data, not just perform well on the training data set. The error on the training data is typically a biased estimate of the generalization error. The training set error tends to be smaller than the generalization error if the model is selected such that it minimizes the training error. Therefore, the training error alone should not be used as a good predictor of …

Image Compression By Vector Quantization Of Dct Coefficients Using A Self-Organizing Neural Network, Kirankumar Boyapati

Electrical & Computer Engineering Theses & Dissertations

Image compression is used to remove different types of redundancies and irrelevant information in an image so that the space required for storing the image is minimized. Conventional transform based techniques remove the redundancies between adjacent pixels and irrelevant information in the image but fail to remove the redundancies between different parts of the image. There are techniques like vector quantization, which take care of the redundant information in different parts of the image, but fail to remove the irrelevant information in the image. In this thesis a new technique for lossy digital image compression is proposed which is a …

Applying A Simulation-Based Real-Time Decision Making Method To Mass Casualty Scenarios In Hospital Emergency Departments, Fatemah Al-Douli

Electrical & Computer Engineering Theses & Dissertations

The high possibility of having a mass casualty incident compels hospitals to plan ahead in order to sufficiently provide the healthcare needed to as many casualty victims as possible. The Emergency Rooms (ER) are usually hospitals' main entrance for many casualties. Therefore, the ER in the Children's Hospital of the King's Daughters (CHKD) was selected as the system to be examined. The ER in CHKD, the only specialized pediatric ER in the region, already struggles to handle very high patient arrival rates. Consequently, it is expected that treating a large number of patients surviving within a very short period of …

Lightweight Federation Of Non-Cooperating Digital Libraries, Rong Shi

Computer Science Theses & Dissertations

This dissertation studies the challenges and issues faced in federating heterogeneous digital libraries (DLs). The objective of this research is to demonstrate the feasibility of interoperability among non-cooperating DLs by presenting a lightweight, data driven approach, or Data Centered Interoperability (DCI). We build a Lightweight Federated Digital Library (LFDL) system to provide federated search service for existing digital libraries with no prior coordination.

We describe the motivation, architecture, design and implementation of the LFDL. We develop, deploy, and evaluate key services of the federation. The major difference to existing DL interoperability approaches is one where we do not insist on …

Clustering And Hybrid Routing In Mobile Ad Hoc Networks, Lan Wang

Computer Science Theses & Dissertations

This dissertation focuses on clustering and hybrid routing in Mobile Ad Hoc Networks (MANET). Specifically, we study two different network-layer virtual infrastructures proposed for MANET: the explicit cluster infrastructure and the implicit zone infrastructure. In the first part of the dissertation, we propose a novel clustering scheme based on a number of properties of diameter-2 graphs to provide a general-purpose virtual infrastructure for MANET. Compared to virtual infrastructures with central nodes, our virtual infrastructure is more symmetric and stable, but still light-weight. In our clustering scheme, cluster initialization naturally blends into cluster maintenance, showing the unity between these two operations. …

Software Development Project Risk Management: A Literature Review, Kevin Macg. Adams, C. Ariel Pinto

Engineering Management & Systems Engineering Faculty Publications

The rapid and unprecedented growth in software has brought with it some of the most spectacular and costly project failures in modern history. How risk management is presented in the scholarly journals may give insight into the risk management methods and techniques in use on software development projects. This paper provides a glimpse into the risk management methods, methodologies and techniques available to those who are responsible for software development projects by conducting a non-experimental content analysis. The findings reveal that risk management has not received sufficient attention and does not appear to be widely accepted within the software engineering …

Review Of Internet Invention: From Literacy To Electracy, By Gregory L. Ulmer, 2003, Alan Clinton

Reconstruction: Studies in Contemporary Culture

No abstract provided.

Implementing Simple Protocols In Multiple Processors Control Applications, Steve Hsiung, Tyson Mccall, Corinne Ransberger

Engineering Technology Faculty Publications

Using microprocessor/microcontroller in various control applications is not only one of the major topics in Engineering Technology curricula, but also of interest in industry applications. To accomplish it correctly the process of designing application programs starts from the individual module development through extensive testing, verification, and modification. Applying these developed modules in a useful manner requires the links and integrations that lead to the practical project implementation. Frequently, in students' senior project designs and faculty's research plans, the microprocessor/microcontroller resources become scarce or cause conflicts during the modules' integration stage. To accommodate the shortfall of the resources and resolve any …

The Architecture Of A Proteomic Network In The Yeast, Emad Ramadan, Christopher Osgood, Alex Pothern

Biological Sciences Faculty Publications

We describe an approach to clustering the yeast protein-protein inter-action network in order to identify functional modules, groups of proteins forming multi-protein complexes accomplishing various functions in the cell. We have developed a clustering method that accounts for the small-world nature of the network. The algorithm makes use of the concept of k-cores in a graph, and employs recursive spectral clustering to compute the functional modules. The computed clusters are annotated using their protein memberships into known multi-protein complexes in the yeast. We also dissect the protein interaction network into a global subnetwork of hub proteins (connected to several clusters), …

Performance Analysis And Validation Of A Recoverable Flight Control System In A Simulated Neutron Environment, Hong Zhang, W. Steven Gray, Oscar R. Gonzalez

Electrical & Computer Engineering Faculty Publications

This paper introduces a class of stochastic hybrid models for the analysis of closed-loop control systems implemented with NASA's Recoverable Computer System. Such Recoverable Computer Systems have been proposed to insure reliable control performance in harsh environments. The stochastic hybrid models consist of either a stochastic finite-state automaton or a finite-state machine driven by a Markov input, which in turn drives a switched linear discrete-time dynamical system. Their stability and output tracking performance are analyzed using an extension of the existing theory for Markov jump-linear systems. For illustration, a stochastic hybrid model is used to calculate the tracking error performance …

Final Report For The Development Of The Nasa Technical Report Server (Ntrs), Michael L. Nelson

Computer Science Faculty Publications

The author performed a variety of research, development and consulting tasks for NASA Langley Research Center in the area of digital libraries (DLs) and supporting technologies, such as the Open Archives Initiative Protocol for Metadata Harvesting (OAI-PMH). In particular, the development focused on the NASA Technical Report Server (NTRS) and its transition from a distributed searching model to one that uses the OAI-PMH. The Open Archives Initiative (OAI) is an international consortium focused on furthering the interoperability of DLs through the use of "metadata harvesting". The OAI-PMH version of NTRS went into public production on April 28, 2003. Since that …

Lessons Learned With Arc, An Oai-Pmh Service Provider, Xiaoming Liu, Kurt Maly, Michael L. Nelson

Computer Science Faculty Publications

Web-based digital libraries have historically been built in isolation utilizing different technologies, protocols, and metadata. These differences hindered the development of digital library services that enable users to discover information from multiple libraries through a single unified interface. The Open Archives Initiative Protocol for Metadata Harvesting (OAI-PMH) is a major, international effort to address technical interoperability among distributed repositories. Arc debuted in 2000 as the first end-user OAI-PMH service provider. Since that time, Arc has grown to include nearly 7,000,000 metadata records. Arc has been deployed in a number of environments and has served as the basis for many other …

Archive Ingest And Handling Test, Michael L. Nelson, Johan Bollen, Giridhar Manepalli, Rabia Haq

Computer Science Faculty Publications

The Archive Ingest and Handling Test (AIHT) was a Library of Congress (LC) sponsored research project administered by Information Systems and Support Inc. (ISS). The project featured five participants: Old Dominion University Computer Science Department; Harvard University Library; Johns Hopkins University Library; Stanford University Library; Library of Congress. All five participants received identical disk drives containing copies of the 911.gmu.edu web site, a collection of 9/11 materials maintained by George Mason University (GMU). The purpose of the AIHT experiment was to perform archival forensics to determine the nature of the archive, ingest it, simulate at least one of the file …