Open Access. Powered by Scholars. Published by Universities.®

Computer Sciences Commons™

Open Access. Powered by Scholars. Published by Universities.®

2009

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 421 - 450 of 1345

Full-Text Articles in Computer Sciences

Scalable Verification For Outsourced Dynamic Databases, Hwee Hwa Pang, Jilian Zhang, Kyriakos Mouratidis Aug 2009

Scalable Verification For Outsourced Dynamic Databases, Hwee Hwa Pang, Jilian Zhang, Kyriakos Mouratidis

Research Collection School Of Computing and Information Systems

Query answers from servers operated by third parties need to be verified, as the third parties may not be trusted or their servers may be compromised. Most of the existing authentication methods construct validity proofs based on the Merkle hash tree (MHT). The MHT, however, imposes severe concurrency constraints that slow down data updates. We introduce a protocol, built upon signature aggregation, for checking the authenticity, completeness and freshness of query answers. The protocol offers the important property of allowing new data to be disseminated immediately, while ensuring that outdated values beyond a pre-set age can be detected. We also …

Go to article

A Trust-Based Multiagent System, Richard S. Seymour, Gilbert L. Peterson Aug 2009

A Trust-Based Multiagent System, Richard S. Seymour, Gilbert L. Peterson

Faculty Publications

Cooperative agent systems often do not account for sneaky agents who are willing to cooperate when the stakes are low and take selfish, greedy actions when the rewards rise. Trust modeling often focuses on identifying the appropriate trust level for the other agents in the environment and then using these levels to determine how to interact with each agent. Adding trust to an interactive partially observable Markov decision process (I-POMDP) allows trust levels to be continuously monitored and corrected enabling agents to make better decisions. The addition of trust modeling increases the decision process calculations, and solves more complex trust …

Go to article

Statistical Investigation Of Structure In The Discrete Logarithm, Andrew Hoffman Jul 2009

Statistical Investigation Of Structure In The Discrete Logarithm, Andrew Hoffman

Mathematical Sciences Technical Reports (MSTR)

The absence of an efficient algorithm to solve the Discrete Logarithm Problem is often exploited in cryptography. While exponentiation with a modulus is extremely fast with a modern computer, the inverse is decidedly not. At the present time, the best algorithms assume that the inverse mapping is completely random. Yet there is at least some structure, and to uncover additional structure that may be useful in constructing or refining algorithms, statistical methods are employed to compare modular exponential mappings to random mappings. More concretely, structure will be defined by representing the mappings as functional graphs and using parameters from graph …

Go to article

A Distributed Algorithmic Framework For Coverage Problems In Wireless Sensor Networks, Akshaye Dhawan, Sushil K. Prasad Jul 2009

A Distributed Algorithmic Framework For Coverage Problems In Wireless Sensor Networks, Akshaye Dhawan, Sushil K. Prasad

Mathematics, Computer Science & Statistics Faculty Publications

One of the key challenges in Wireless Sensor Networks (WSNs) is that of extending the lifetime of the network while meeting some coverage requirements. In this paper, we present a distributed algorithmic framework to enable sensors to determine their sleep-sense cycles based on specific coverage goals. The framework is based on our earlier work on the target coverage problem. We give a general version of the framework that can be used to solve network/graph optimization problems for which melding compatible neighboring local solutions directly yields globally feasible solutions such as the maximal independent set problem. We also apply this framework …

Go to article

A Hop-By-Hop Architecture For Multicast Transport In Ad Hoc Wireless Networks, Manoj Kumar Pandey Jul 2009

A Hop-By-Hop Architecture For Multicast Transport In Ad Hoc Wireless Networks, Manoj Kumar Pandey

Theses and Dissertations

Ad hoc wireless networks are increasingly being used to provide connectivity where a wired networking infrastructure is either unavailable or inaccessible. Many deployments utilize group communication, where several senders communicate with several receivers; multicasting has long been seen as an efficient way to provide this service. While there has been a great deal of research on multicast routing in ad hoc networks, relatively little attention has been paid to the design of multicast transport protocols, which provide reliability and congestion control. In this dissertation we design and implement a complete multicast transport architecture that includes both routing and transport protocols. …

Go to article

Sound And The City: Multi-Layer Representation And Navigation Of Audio Scenarios, Luca A. Ludovico, Davide Andrea Mauro Phd Jul 2009

Sound And The City: Multi-Layer Representation And Navigation Of Audio Scenarios, Luca A. Ludovico, Davide Andrea Mauro Phd

Computer Sciences and Electrical Engineering Faculty Research

IEEE 1599-2008 is an XML-based standard originally intended for the multi-layer representation of music information. Nevertheless, it is versatile enough to describe also information different from traditional scores written according to the Common Western Notation (CWN) rules. This paper will discuss the application of IEEE 1599-2008 to the audio description of paths and scenarios from the urban life or other landscapes. The standard we adopt allows the multilayer integration of textual, symbolical, structural, graphical, audio and video contents within a unique synchronized environment. Besides, for each kind of media, a number of digital objects is supported. As a consequence, thanks …

Go to article

Knowledge Discovery Over The Deep Web, Semantic Web And Xml, Aparna Varde, Fabian Suchanek, Richi Nayak, Pierre Senellart Jul 2009

Knowledge Discovery Over The Deep Web, Semantic Web And Xml, Aparna Varde, Fabian Suchanek, Richi Nayak, Pierre Senellart

Department of Computer Science Faculty Scholarship and Creative Works

In this tutorial we provide an insight into Web Mining, i.e., discovering knowledge from the World Wide Web, especially with reference to the latest developments in Web technology. The topics covered are: the Deep Web, also known as the Hidden Web or Invisible Web; the Semantic Web including standards such as RDFS and OWL; the eXtensible Markup Language XML, a widespread communication medium for the Web; and domain-specific markup languages defined within the context of XML We explain how each of these developments support knowledge discovery from data stored over the Web, thereby assisting several real-world applications.

Go to article

An Investigation Into The Development Of A Practical Gis Mapping Tool Supporting Emissions Inventory Information, Elizabeth J. Davis-Noland Jul 2009

An Investigation Into The Development Of A Practical Gis Mapping Tool Supporting Emissions Inventory Information, Elizabeth J. Davis-Noland

Regis University Student Publications (comprehensive collection)

Environmental Protection Agency (EPA) regulations call for States to submit for EPA review and approval State Implementation Plans (SIPs) which establish goals and emission reduction strategies for improving air quality in national parks and wilderness areas. State and tribe air quality analysts therefore need the ability to display and analyze emissions inventory data in relation to geographic locations. However, due to budget and other constraints, traditional Graphical Information Systems (GIS) tools are often not available. Today, traditional GIS are being challenged in various domains by a variety of free or low-cost internet accessible services. Leveraging the availability of the Google …

Go to article

Open Forum: The Future Of Library Systems, Maria Collins, Andrée J. Rathemacher Jul 2009

Open Forum: The Future Of Library Systems, Maria Collins, Andrée J. Rathemacher

Technical Services Faculty Publications

Moderated by Maria Collins of North Carolina State University, discussion at this open forum on the future of library systems touched on open-source library systems, cloud computing, new initiatives by the Open Library Environment (OLE) Project and OCLC, and desired characteristics of future integrated library systems. Most participants had limited experience with next-generation library systems and attended the open forum with the desire to broaden their understanding, although some were exposed to or had worked with the open-source discovery tool VuFind, the OLE Project, WorldCat Local, and the OCLC Web-scale service. A strong desire to customize library systems to meet …

Go to article

Formal Verification Of Scalable Nonzero Indicators, Jun Sun, Yang Liu, Jun Sun, Jin Song Dong, Wei Chen, Yanhong A. Liu Jul 2009

Formal Verification Of Scalable Nonzero Indicators, Jun Sun, Yang Liu, Jun Sun, Jin Song Dong, Wei Chen, Yanhong A. Liu

Research Collection School Of Computing and Information Systems

Concurrent algorithms are notoriously difficult to design correctly, and high performance algorithms that make little or no use of locks even more so. In this paper, we describe a formal verification of a recent concurrent data structure Scalable NonZero Indicators. The algorithm supports incrementing, decrementing, and querying the shared counter in an efficient and linearizable way without blocking. The algorithm is highly non-trivial and it is challenging to prove the correctness. We have proved that the algorithm satisfies linearizability, by showing a trace refinement relation from the concrete implementation to its abstract specification. These models are specified in CSP and …

Go to article

Musical Query-By-Content Using Self-Organizing Maps, Kyle B. Dickerson Jul 2009

Musical Query-By-Content Using Self-Organizing Maps, Kyle B. Dickerson

Theses and Dissertations

The ever-increasing density of computer storage devices has allowed the average user to store enormous quantities of multimedia content, and a large amount of this content is usually music. Current search techniques for musical content rely on meta-data tags which describe artist, album, year, genre, etc. Query-by-content systems, however, allow users to search based upon the actual acoustical content of the songs. Recent systems have mainly depended upon textual representations of the queries and targets in order to apply common string-matching algorithms and are often confined to a single query style (e.g., humming). These methods also lose much of the …

Go to article

Joint Routing And Link Rate Allocation Under Bandwidth And Energy Constraints In Sensor Networks, Maggie Cheng, Xuan Gong, Lin Cai Jul 2009

Joint Routing And Link Rate Allocation Under Bandwidth And Energy Constraints In Sensor Networks, Maggie Cheng, Xuan Gong, Lin Cai

Computer Science Faculty Research & Creative Works

In sensor networks, both energy and bandwidth are scarce resources. in the past, many energies efficient routing algorithms have been devised in order to maximize network lifetime, in which wireless link bandwidth has been optimistically assumed to be sufficient. This article shows that ignoring the bandwidth constraint can lead to infeasible routing solutions. as energy constraint affects how data should be routed, link bandwidth also affects not only the routing topology but also the allowed data rate on each link. in this paper, we discuss the sufficient condition on link bandwidth that makes a routing solution feasible, then provide mathematical …

Go to article

Validation Of The Principal’S Computer Technology Survey, Lantry Brockmeier, Nicole Gibson Jul 2009

Validation Of The Principal’S Computer Technology Survey, Lantry Brockmeier, Nicole Gibson

Georgia Educational Researcher

The purpose of this study was to provide a more in-depth analysis of the psychometric characteristics of the Principal’s Computer Technology Survey (PCTS). The PCTS developmental process yielded a 40–item survey with groups of items comprising five subscales (i.e., curriculum integration, perceptions, acquired expertise, needs assessment, and professional development). Principals’ responses to items within the five subscales was measured on a five-point Likert scale ranging from 1 (strongly disagree) to 5 (strongly agree). An expert panel reviewed the instrument plus exploratory factor analyses and confirmatory factor analyses were conducted. This analysis resulted in a restructured instrument …

Go to article

Consistency Management Strategies For Data Replication In Mobile Ad Hoc Networks, Takahiro Hara, Sanjay Kumar Madria Jul 2009

Consistency Management Strategies For Data Replication In Mobile Ad Hoc Networks, Takahiro Hara, Sanjay Kumar Madria

Computer Science Faculty Research & Creative Works

In a mobile ad hoc network, data replication drastically improves data availability. However, since mobile hosts' mobility causes frequent network partitioning, consistency management of data operations on replicas becomes a crucial issue. In such an environment, the global consistency of data operations on replicas is not desirable by many applications. Thus, new consistency maintenance based on local conditions such as location and time need to be investigated. This paper attempts to classify different consistency levels according to requirements from applications and provides protocols to realize them. We report simulation results to investigate the characteristics of these consistency protocols in a …

Go to article

Report On The First International Workshop On Innovation In Digital Preservation (Indp 2009), Frank Mccown Ph.D., Hannes Kulovits, Andreas Rauber Jul 2009

Report On The First International Workshop On Innovation In Digital Preservation (Indp 2009), Frank Mccown Ph.D., Hannes Kulovits, Andreas Rauber

Faculty Research and Publications

Information about several topics discussed at the First International Workshop on Innovation in Digital Preservation (InDP 2009) on June 19, 2009 in Austin, Texas is presented. Topics include the collection of digital objects, web pages transition, and digital preservation (DP). The workshop featured presenters Rudolf Mayer, Martin Klein and Dominick Heutelbeck.

Go to article

Virtual Wired Transmission Scheme - A Novel Technique For Efficient Mobile Adhoc Networks, Manikya Vinay Rali Jul 2009

Virtual Wired Transmission Scheme - A Novel Technique For Efficient Mobile Adhoc Networks, Manikya Vinay Rali

Electrical & Computer Engineering Theses & Dissertations

This thesis proposes a method called virtual wired transmission scheme for ad hoc networks. The scheme is an efficient method to improve network performance parameters such as energy efficiency, capacity, interference, network throughput, etc. Performance parameters improvement can be done at different layers of the network architecture for mobile ad hoc networks. However most of the research efforts are concentrated on Physical, MAC and Network layers. In this thesis, a MAC protocol with a major MAC layer modification is proposed in combination with the usage of directional antennas, developing a novel method called virtual wired transmission scheme. In virtual wired …

Go to article

Brain Tumor Progression Assessment Using Multiple Mri Volumes, Yufei Shen Jul 2009

Brain Tumor Progression Assessment Using Multiple Mri Volumes, Yufei Shen

Electrical & Computer Engineering Theses & Dissertations

Predicting and assessing tumor progression is important in brain tumor treatment. We attempt to use machine learning techniques to achieve consistency in assessing brain tumor progression. This thesis presents a prediction method of brain tumor progression by exploring a large MR database, which contains two patients ' complete records covering all their visits in the past two years. All ten MRI series, namely, apparent diffusion coefficient (ADC) , diffusion tensor imaging (DTI) , fractional anisotropy (FA), fluid attenuated inversion recovery (FLAIR), max eigenvalue (MAX), mid eigenvalue (MID), min eigenvalue (MIN) , post-contrast T1-weighted, T1- weighted, and …

Go to article

Distributed Monitoring Of Conditional Entropy For Network Anomaly Detection, Chrisil Arackaparambil, Sergey Bratus, Joshua Brody, Anna Shubina Jul 2009

Distributed Monitoring Of Conditional Entropy For Network Anomaly Detection, Chrisil Arackaparambil, Sergey Bratus, Joshua Brody, Anna Shubina

Computer Science Technical Reports

Monitoring the empirical Shannon entropy of a feature in a network packet stream has previously been shown to be useful in detecting anomalies in the network traffic. Entropy is an information-theoretic statistic that measures the variability of the feature under consideration. Anomalous activity in network traffic can be captured by detecting changes in this variability. There are several challenges, however, in monitoring this statistic. Computing the statistic efficiently is non-trivial. Further, when monitoring multiple features, the streaming algorithms proposed previously would likely fail to keep up with the ever-increasing channel bandwidth of network traffic streams. There is also the concern …

Go to article

The Potential Use Of Slow-Down Technology To Improve Pronounciation Of English For International Communication, Bunny Richardson Jul 2009

The Potential Use Of Slow-Down Technology To Improve Pronounciation Of English For International Communication, Bunny Richardson

Doctoral

The focus of this research is on oral communication between L1 (first language) and L2 (second language) English users - to determine whether an algorithm which slows down speech can increase the intelligibility of speech between interlocutors for EIC (English for International Communication). The slow-down facility is a CALL tool which slows down speech without tonal distortion. It allows English language learners more processing time to hear individual phonemes as produced in the stream of connected speech, to help them hear and produce phonemes more accurately and thus more intelligibly. The study involved five tests, all concerned with the intelligibility …

Go to article

Section Abstracts: Computer Science Jul 2009

Section Abstracts: Computer Science

Virginia Journal of Science

Abstracts of the Computer Science for the 87th Annual Meeting of the Virginia Academy of Science, May 27-29, 2009, Virginia Commonwealth University, Richmond Virginia.

Go to article

Cs 206: Advanced Concepts/Techniques And Software Productivity Tools, Terri Bauer Jul 2009

Cs 206: Advanced Concepts/Techniques And Software Productivity Tools, Terri Bauer

Computer Science & Engineering Syllabi

By the end of this course, the students will have a greater depth of understanding in the areas of spreadsheets, databases, and presentation software and web design using Microsoft Excel, Access, and PowerPoint covering the following topics.
Microsoft Excel 2007:
Chapters 4 -6
Microsoft Access 2007:
Chapters 4 -6
Microsoft PowerPoint 2007:
Chapter 3 & 4

Go to article

“Best K”: Critical Clustering Structures In Categorical Datasets, Keke Chen, Ling Liu Jul 2009

“Best K”: Critical Clustering Structures In Categorical Datasets, Keke Chen, Ling Liu

Kno.e.sis Publications

The demand on cluster analysis for categorical data continues to grow over the last decade. A well-known problem in categorical clustering is to determine the best K number of clusters. Although several categorical clustering algorithms have been developed, surprisingly, none has satisfactorily addressed the problem of best K for categorical clustering. Since categorical data does not have an inherent distance function as the similarity measure, traditional cluster validation techniques based on geometric shapes and density distributions are not appropriate for categorical data. In this paper, we study the entropy property between the clustering results of categorical data with different K …

Go to article

Tableau Algorithm For Concept Satisfiability In Description Logic Alch, Satya S. Sahoo, Krishnaprasad Thirunarayan Jul 2009

Tableau Algorithm For Concept Satisfiability In Description Logic Alch, Satya S. Sahoo, Krishnaprasad Thirunarayan

Kno.e.sis Publications

The provenir ontology is an upper-level ontology to facilitate interoperability of provenance information in scientific applications. The description logic (DL) expressivity of provenir ontology is ALCH, that is, it models role hierarchies (H) (without transitive roles and inverse roles). Even though the complexity results for concept satisfiability for numerous variants of DL such as ALC with transitively closed roles (ALCR+ also called S), inverse roles SI, and role hierarchy SHI have been well-established, similar results for ALCH has been surprisingly missing from the literature. Here, we show that the complexity of the concept satisfiability problem for the ALCH variant …

Go to article

Rfid-Based Smart Freezer, Ahmet Soylemezoglu, Maciej Jan Zawodniok, Jagannathan Sarangapani Jul 2009

Rfid-Based Smart Freezer, Ahmet Soylemezoglu, Maciej Jan Zawodniok, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a novel radio-frequency identification (RFID)-based smart freezer using a new inventory-management scheme for extremely low temperature environments. The proposed solution utilizes backpressure inventory control, systematic selection of antenna configuration, and antenna power control. The proposed distributed-inventory-control (DIC) scheme dictates the amount of items transferred through the supply chain. when a high item visibility is ensured, the control scheme maintains the desired level of inventory at each supply-chain echelon. The performance of the DIC scheme is guaranteed using a Lyapunov-based analysis. The proposed RFID antenna-configuration design methodology coupled with locally asymptotically stable distributed power control ensures a 99% …

Go to article

Optimal Control Of Unknown Affine Nonlinear Discrete-Time Systems Using Offline-Trained Neural Networks With Proof Of Convergence, Travis Dierks, Balaje T. Thumati, S. Jagannathan Jul 2009

Optimal Control Of Unknown Affine Nonlinear Discrete-Time Systems Using Offline-Trained Neural Networks With Proof Of Convergence, Travis Dierks, Balaje T. Thumati, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

The optimal control of linear systems accompanied by quadratic cost functions can be achieved by solving the well-known Riccati equation. However, the optimal control of nonlinear discrete-time systems is a much more challenging task that often requires solving the nonlinear Hamilton-Jacobi-Bellman (HJB) equation. in the recent literature, discrete-time approximate dynamic programming (ADP) techniques have been widely used to determine the optimal or near optimal control policies for affine nonlinear discrete-time systems. However, an inherent assumption of ADP requires the value of the controlled system one step ahead and at least partial knowledge of the system dynamics to be known. in …

Go to article

Cs 470/670: System Simulation, Mateen M. Rizki Jul 2009

Cs 470/670: System Simulation, Mateen M. Rizki

Computer Science & Engineering Syllabi

No abstract provided.

Go to article

Cs 241: Computer Programming Ii, Travis E. Doom Jul 2009

Cs 241: Computer Programming Ii, Travis E. Doom

Computer Science & Engineering Syllabi

A continuation of CS240. The emphasis is on data abstraction and software engineering. Prerequisite: CS240.

Go to article

Cs 480/680: Comparative Languages, Krishnaprasad Thirunarayan Jul 2009

Cs 480/680: Comparative Languages, Krishnaprasad Thirunarayan

Computer Science & Engineering Syllabi

This course will introduce fundamental concepts and paradigms underlying the design of modern programming languages. For concreteness, we study the details of an object-oriented language (e.g. Java), and a functional language (e.g., Scheme) . The overall goal is to enable comparison and evaluation of existing languages. The programming assignments will be coded in Java 5 and in Scheme.

Go to article

Cs 701: Database Systems And Design I, Guozhu Dong Jul 2009

Cs 701: Database Systems And Design I, Guozhu Dong

Computer Science & Engineering Syllabi

An introduction to database design, database system implementation issues and techniques, and advanced data models and concepts.

Go to article

Cs 765: Foundations Of Neurocomputation, John C. Gallagher Jul 2009

Cs 765: Foundations Of Neurocomputation, John C. Gallagher

Computer Science & Engineering Syllabi

This course is designed to help you develop a solid understanding of neural network algorithms and architectures. At the end of this course you should be able to read and critically evaluate most neural network papers published in major journals, (e.g. IEEE Transaction on Neural Networks, Neural Networks, and Neural Computation). In addition, you should be able to implement a broad range of network architectures and learning algorithms for a variety of applications.

Go to article

First Prev Next Last