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Using The Emulab Network Testbed To Evaluate The Armada I/O Framework For Computational Grids, Ron Oldfield, David Kotz Sep 2002

Using The Emulab Network Testbed To Evaluate The Armada I/O Framework For Computational Grids, Ron Oldfield, David Kotz

Computer Science Technical Reports

This short report describes our experiences using the Emulab network testbed at the University of Utah to test performance of the Armada framework for parallel I/O on computational grids.


Data, Information, And Knowledge In The Context Of Sils, Michael A. Zang, Jens G. Pohl Sep 2002

Data, Information, And Knowledge In The Context Of Sils, Michael A. Zang, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

Data, information, and knowledge are becoming increasingly common terms in the literature of the software industry. This terminology originated some time ago in the disciplines of cognitive science and artificial intelligence to reference three closely related but distinct concepts. Traditionally, mainstream software engineering has lumped all three concepts together as data and has only recently begun to distinguish between them. Unfortunately, the popular desire to distinguish between data, information, and knowledge within the mainstream has blurred the individual meanings of the words to the point where there is no longer a clear-cut distinction between them for most people. This problem …


Performance Evaluation Of Linear Hash Structure Model In A Nested Transaction Environment, Malik Ayed Tubaishat, Sanjay Kumar Madria, Bharat Bhargava Sep 2002

Performance Evaluation Of Linear Hash Structure Model In A Nested Transaction Environment, Malik Ayed Tubaishat, Sanjay Kumar Madria, Bharat Bhargava

Computer Science Faculty Research & Creative Works

We design and implement a linear hash algorithm in nested transaction environment to handle large amount of data with increased concurrency. Nested transactions allow parallel execution of transactions, and handle transaction aborts, thus provides more concurrency and efficient recovery. We use object-oriented methodology in the implementation which helped in designing the programming components independently. In our model, buckets are modeled as objects and linear hash operations are modeled as methods. The papers contribution is novel in the sense that the system, to our knowledge, is the first to implement linear hashing in a nested transactions environment. We have built a …


Heterogeneous Self-Reconfiguring Robotics: Ph.D. Thesis Proposal, Robert C. Fitch Sep 2002

Heterogeneous Self-Reconfiguring Robotics: Ph.D. Thesis Proposal, Robert C. Fitch

Computer Science Technical Reports

Self-reconfiguring robots are modular systems that can change shape, or "reconfigure," to match structure to task. They comprise many small, discrete, often identical modules that connect together and that are minimally actuated. Global shape transformation is achieved by composing local motions. Systems with a single module type, known as "homogeneous" systems, gain fault tolerance, robustness and low production cost from module interchangeability. However, we are interested in "heterogeneous" systems, which include multiple types of modules such as those with sensors, batteries or wheels. We believe that heterogeneous systems offer the same benefits as homogeneous systems with the added ability to …


Ipr : Information Technology, Subhashish Gupta Sep 2002

Ipr : Information Technology, Subhashish Gupta

IIMB Management Review

How does one protect intellectual property in an intangible digital economy? Can mere ideas or algorithms be patented? Why is it that software can be patented in some circumstances and not in others? Are we barking up the wrong tree in pursuing patents while most IT technologies are related to standards? Discussing these issues and more are Shamnad Basheer, IT Attorney; T R Madanmohan, Associate Professor, IIMB and S D Sherlekar, Principal Consultant (Embedded Systems) at TCS Bangalore. Computer software, pointed out Shamnad Basheer, can be legally protected by patenting the software, copyrighting the source code and protecting the software …


Analysis Of A Campus-Wide Wireless Network, David Kotz, Kobby Essien Sep 2002

Analysis Of A Campus-Wide Wireless Network, David Kotz, Kobby Essien

Computer Science Technical Reports

Understanding usage patterns in wireless local-area networks (WLANs) is critical for those who develop, deploy, and manage WLAN technology, as well as those who develop systems and application software for wireless networks. This paper presents results from the largest and most comprehensive trace of network activity in a large, production wireless LAN. For eleven weeks we traced the activity of nearly two thousand users drawn from a general campus population, using a campus-wide network of 476 access points spread over 161 buildings. Our study expands on those done by Tang and Baker, with a significantly larger and broader population. We …


Digital Image Similarity For Geo-Spatial Knowledge Management, James Carswell Sep 2002

Digital Image Similarity For Geo-Spatial Knowledge Management, James Carswell

Conference papers

The amount and availability of high-quality geo-spatial image data, such as digital satellite and aerial photographs, is increasing dramatically. Task-based management of such visual information and associated knowledge is a central concern for organisations that rely on digital imagery. We are developing geo-spatial knowledge management techniques that employ case-based reasoning as the core methodology. In order to provide effective retrieval of task-based experiences that center around geo-spatial imagery, we need to forward novel similarity metrics for directly comparing the image components of experience cases. Based on work in geo-spatial image database retrieval, we are building an effective similarity metric for …


A Label-Switching Packet Forwarding Architecture For Multi-Hop Wireless Lans, Arup Acharya, Archan Misra, Sorav Bansal Sep 2002

A Label-Switching Packet Forwarding Architecture For Multi-Hop Wireless Lans, Arup Acharya, Archan Misra, Sorav Bansal

Research Collection School Of Computing and Information Systems

A router in wired network typically requires multiple network interfaces to act as a router or a forwarding node. In an ad-hoc multi-hop wireless network on the other hand, any node with a wireless network interface card can operate as a router or a forwarding node, since it can receive a packet from a neighboring node, do a route lookup based on the packet's destination IP address, and then transmit the packet to another neighboring node using the same wireless interface. This paper investigates a combined medium access and next-hop address lookup based on fixed length labels (instead of IP …


Cryptanalysis Of Some Hash Functions Based On Block Ciphers And Codes, Hongjun Wu, Feng Bao, Robert Huijie Deng Sep 2002

Cryptanalysis Of Some Hash Functions Based On Block Ciphers And Codes, Hongjun Wu, Feng Bao, Robert Huijie Deng

Research Collection School Of Computing and Information Systems

At PKC 2000, Inoue and Sakurai proposed some methods to design hash functions from block ciphers and codes (block codes and convolutional codes). They claimed that their hash functions are secure: 2(d-1)m/2 encryptions are necessary to find a collision, where d and m are the minimal distance of the code and the block size of block cipher, respectively. However, we show in this paper that a collision could be found with about a.2m encryptions, where a is a small number.


Personalized Classification For Keyword-Based Category Profiles, Aixin Sun, Ee Peng Lim, Wee-Keong Ng Sep 2002

Personalized Classification For Keyword-Based Category Profiles, Aixin Sun, Ee Peng Lim, Wee-Keong Ng

Research Collection School Of Computing and Information Systems

Personalized classification refers to allowing users to define their own categories and automating the assignment of documents to these categories. In this paper, we examine the use of keywords to define personalized categories and propose the use of Support Vector Machine (SVM) to perform personalized classification. Two scenarios have been investigated. The first assumes that the personalized categories are defined in a flat category space. The second assumes that each personalized category is defined within a pre-defined general category that provides a more specific context for the personalized category. The training documents for personalized categories are obtained from a training …


Pickup And Delivery Problem With Time Windows: Algorithms And Test Case Generation, Hoong Chuin Lau, Zhe Liang Sep 2002

Pickup And Delivery Problem With Time Windows: Algorithms And Test Case Generation, Hoong Chuin Lau, Zhe Liang

Research Collection School Of Computing and Information Systems

In the pickup and delivery problem with time windows (PDPTW), vehicles have to transport loads from origins to destinations respecting capacity and time constraints. In this paper, we present a two-phase method to solve the PDPTW. In the first phase, we apply a novel construction heuristics to generate an initial solution. In the second phase, a tabu search method is proposed to improve the solution. Another contribution of this paper is a strategy to generate good problem instances and benchmarking solutions for PDPTW, based on Solomon' s benchmark test cases for VRPTW. Experimental results show that our approach yields very …


Knowledge Discovery And Modeling In Genomic Databases, Michael M. Yin Aug 2002

Knowledge Discovery And Modeling In Genomic Databases, Michael M. Yin

Dissertations

This dissertation research is targeted toward developing effective and accurate methods for identifying gene structures in the genomes of high eukaryotes, such as vertebrate organisms. Several effective hidden Markov models (HMMs) are developed to represent the consensus and degeneracy features of the functional sites including protein-translation start sites, mRNA splicing junction donor and acceptor sites in vertebrate genes. The HMM system based on the developed models is fully trained using an expectation maximization (EM) algorithm and the system performance is evaluated using a 10-way cross-validation method. Experimental results show that the proposed HMM system achieves high sensitivity and specificity in …


Statistical Image Analysis Of Spotted Arrays, Filippo Posta Aug 2002

Statistical Image Analysis Of Spotted Arrays, Filippo Posta

Theses

There is a lot of systematic and specific variability in microarray experiments, this variability affects measured gene expression levels, leading to unreliable gene profiling or an heavy load of extra experiment to statistically confirm the data observed in one experiment.

The aim of this work is to systematically analyze, using statistics, the image derived from a cDNA microarray experiment to have a better understanding of this variability and thus a better confidence over the data obtained from an experiment.

Using technologies available at the Center for Applied Genomics, Newark, New Jersey. Selected images derived from different type of microarray experiments …


An Algorithm For Estimating The Quality Of Microarrays, Ajeet S. Sodhi Aug 2002

An Algorithm For Estimating The Quality Of Microarrays, Ajeet S. Sodhi

Theses

Microarray technology is currently one of the most valuable gene expression tools in molecular biology allowing the experimenter to simultaneously quantify the expression of thousands of genes. It is also one of the most difficult tools to use accurately as each microarray produces a large amount of information that needs to be inspected and normalized before analysis. As the size of a microarray or number of replicates increase, the use of manual inspection becomes impractical. The aim of this thesis is to introduce an algorithm that evaluates each feature of a microarray from the scanned data file. A quality score …


Analysis For Cooperative Behavior Effectiveness Of Autonomous Wide Area Search Munitions, Sang M. Park Aug 2002

Analysis For Cooperative Behavior Effectiveness Of Autonomous Wide Area Search Munitions, Sang M. Park

Theses and Dissertations

The purpose of this study is to investigate how a simulation model can accurately represent the performance of the autonomous wide area search munitions, and to find the effectiveness of the cooperative behavior on the autonomous munitions. Though it does not provide a practical solution for the development of the autonomous wide area search munitions, this research will show some meaningful allocations of the munitions tasks that are applicable to the development of the autonomous munitions. For the first phase, this thesis presents how accurately a simplified simulation model can represent a proposed weapon system by comparing the simulation results …


Object-Oriented Modeling And Fauly Detection Of A Powder Feeder For A Laser Metal Deposition System, Robert G. Landers, Michael Gene Hilgers, Frank W. Liou, Bruce M. Mcmillin Aug 2002

Object-Oriented Modeling And Fauly Detection Of A Powder Feeder For A Laser Metal Deposition System, Robert G. Landers, Michael Gene Hilgers, Frank W. Liou, Bruce M. Mcmillin

Mechanical and Aerospace Engineering Faculty Research & Creative Works

One of the most critical components of a laser metal deposition system is the powder feeder unit. Techniques are required to efficiently design and analyze these systems and to ensure fault tolerance during the operation. In this paper, a model of the powder feeder unit, based on object- oriented abstractions of it components, is developed. This model is modular in that specific components can be efficiently updated or replaced with components that perform a similar function. In addition, the model can be used for simulation allowing for efficient design and analysis. Assurance of the correctness of the powder feeder system …


Object-Oriented Modeling And Fault Detection Of A Powder Feeder For A Laser Metal Deposition System, Robert G. Landers, Michael Gene Hilgers, Frank W. Liou, Bruce M. Mcmillin Aug 2002

Object-Oriented Modeling And Fault Detection Of A Powder Feeder For A Laser Metal Deposition System, Robert G. Landers, Michael Gene Hilgers, Frank W. Liou, Bruce M. Mcmillin

Mechanical and Aerospace Engineering Faculty Research & Creative Works

One of the most critical components of a laser metal deposition system is the powder feeder unit. Techniques are required to efficiently design and analyze these systems and to ensure fault tolerance during the operation. In this paper, a model of the powder feeder unit, based on object-oriented abstractions of it components, is developed. This model is modular in that specific components can be efficiently updated or replaced with components that perform a similar function. In addition, the model can be used for simulation allowing for efficient design and analysis. Assurance of the correctness of the powder feeder system is …


Underwater Video Survey: Planning And Data Processing, Yuri Rzhanov, Lloyd C. Huff, Randy G. Cutter Jr. Aug 2002

Underwater Video Survey: Planning And Data Processing, Yuri Rzhanov, Lloyd C. Huff, Randy G. Cutter Jr.

Center for Coastal and Ocean Mapping

The importance of underwater video surveys as an exploration tool has been steadily increasing over recent years [1]. Better photographic equipment, more effective sources of illumination, and improved processing techniques - all make video surveying a reliable tool for seafloor habitat mapping, sediment boundary delineation and groundtruthing, mapping and documentation of forensic and archaeological sites. There is a change in attitude towards video surveying that affects the way the data is collected, and hence its quality. Earlier video data processing algorithms had to cope with whatever was recorded (often simultaneously with acquisition of other data, considered to be more important). …


Visual Execution Analysis For Multiagent Systems, Chong Kil Aug 2002

Visual Execution Analysis For Multiagent Systems, Chong Kil

Theses and Dissertations

Multiagent systems have become increasingly important in developing complex software systems. Multiagent systems introduce collective intelligence and provide benefits such as flexibility, scalability, decentralization, and increased reliability. A software agent is a high-level software abstraction that is capable of performing given tasks in an environment without human intervention. Although multiagent systems provide a convenient and powerful way to organize complex software systems, developing such system is very complicated. To help manage this complexity this research develops a methodology and technique for analyzing, monitoring and troubleshooting multiagent systems execution. This is accomplished by visualizing a multiagent system at multiple levels of …


Scalable And Reliable File Transfer For Clusters Using Multicast., Hardik Dikpal Shukla Aug 2002

Scalable And Reliable File Transfer For Clusters Using Multicast., Hardik Dikpal Shukla

Electronic Theses and Dissertations

A cluster is a group of computing resources that are connected by a single computer network and are managed as a single system. Clusters potentially have three key advantages over workstations operated in isolation—fault tolerance, load balancing and support for distributed computing.

Information sharing among the cluster’s resources affects all phases of cluster administration. The thesis describes a new tool for distributing files within clusters. This tool, the Scalable and Reliable File Transfer Tool (SRFTT), uses Forward Error Correction (FEC) and multiple multicast channels to achieve an efficient reliable file transfer, relative to heterogeneous clusters. SRFTT achieves scalability …


Similarity Join For Low- And High-Dimensional Data, Dmitri V. Kalashnikov, Sunil Prabhakar Aug 2002

Similarity Join For Low- And High-Dimensional Data, Dmitri V. Kalashnikov, Sunil Prabhakar

Department of Computer Science Technical Reports

No abstract provided.


On Efficient On-Line Grouping Of Flows With Shared Bottlenecks At Loaded Servers, Ossama Younis, Sonia Fahmy Aug 2002

On Efficient On-Line Grouping Of Flows With Shared Bottlenecks At Loaded Servers, Ossama Younis, Sonia Fahmy

Department of Computer Science Technical Reports

No abstract provided.


Integrated Software System For The Collection And Evaluation Of Wellness Information., Rebecca Elizabeth Sweeney Aug 2002

Integrated Software System For The Collection And Evaluation Of Wellness Information., Rebecca Elizabeth Sweeney

Electronic Theses and Dissertations

There is an absence of a complete, easy to use, software system that can evaluate all areas of wellness. Although there are software programs and equipment available to examine certain aspects of wellness, they are incomplete. The solution to the difficulties of assessing wellness is the design and development of a software system that can be used to collect and evaluate wellness information. The system allows for complete reporting as it entails the six major components to wellness: demographics, body composition, lab work, nutritional intake, physical activity, and body measures. The system allows for ease of use by providing a …


Hci Research Issues In Electronic Commerce, Fiona Fui-Hoon Nah, Sid Davis Aug 2002

Hci Research Issues In Electronic Commerce, Fiona Fui-Hoon Nah, Sid Davis

Research Collection School Of Computing and Information Systems

This article outlines a number of important research issues in human-computer interaction in the e-commerce environment. It highlights some of the challenges faced by users in browsing Web sites and conducting searches for information, and suggests several areas of research for promoting ease of navigation and search. Also, it discusses the importance of trust in the online environment, describing some of the antecedents and consequences of trust, and provides guidelines for integrating trust into Web site design. The issues discussed in this article are presented under three broad categories of human-computer interaction – Web usability, interface design, and trust – …


Detection Of Slide Transition For Topic Indexing, Chong-Wah Ngo, Ting-Chuen Pong, Thomas S. Huang Aug 2002

Detection Of Slide Transition For Topic Indexing, Chong-Wah Ngo, Ting-Chuen Pong, Thomas S. Huang

Research Collection School Of Computing and Information Systems

This paper presents an automatic and novel approach in detecting the transitions of slides for video sequences of technical lectures. Our approach adopts a foreground vs background segmentation algorithm to separate a presenter from the projected electronic slides. Once a background template is generated, text captions are detected and analyzed. The segmented caption regions as well as background templates together provide salient visual cues to decide whether a slide is flipped and replaced. The partitioning of videos according to slide changes not only structure the content of video according to topics, but also facilitate the synchronization of video, audio and …


Context Building Information-Centric Decision-Support Systems, Steven J. Gollery, Jens G. Pohl Jul 2002

Context Building Information-Centric Decision-Support Systems, Steven J. Gollery, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

As the volume of data and human-centered information available to decision-makers continues to increase at an ever-accelerating rate, the need to represent information in software-processable formats becomes more apparent. At the same time, the availability of information from diverse sources through the World Wide Web provides the opportunity to widen the scope of input to decision-support systems, if this information can be made accessible through automated means. Past approaches to information-centric interoperability have been based on the use of a shared static object model, but this becomes impractical when we consider the loosely-coupled decentralized nature of the Web.

This paper …


Some Thoughts On Human Nature: A Discussion Of Human Strenghts And Weaknesses, Jens G. Pohl Jul 2002

Some Thoughts On Human Nature: A Discussion Of Human Strenghts And Weaknesses, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

This paper attempts to explore the behavioral characteristics of human beings from a point of view that is not based on inter-human comparisons, but on an examination of the intrinsic physical, biological, intellectual, emotional, and social characteristics of this species. It is argued that the experience-based nature of the human cognitive system greatly reduces our ability to adapt to changes in our environment, exploit opportunities, and create new knowledge. A fundamental biological survival instinct drives the human being to seek a level of certainty and security that is irreconcilable with a continuously changing and largely unpredictable environment. The symptoms of …


Design And Implementation Of An Online Database Panel, Frenny Thomas Jul 2002

Design And Implementation Of An Online Database Panel, Frenny Thomas

Theses and Dissertations

There is a growing need for administrative panels such as the one described in this project. More and more website administrators wish to make changes to their online business without having to directly modify the database file. This project provides the perfect solution for this scenario by placing all database access on the World Wide Web. Administrators can now use this software to add, edit, and delete tables, fields, and records. Additionally, users will be able to generate queries without knowledge of Structured Query Language. This project acts as a summary of my computer science education at this university by …


The Future Of Cryptography Under Quantum Computers, Marco A. Barreno Jul 2002

The Future Of Cryptography Under Quantum Computers, Marco A. Barreno

Dartmouth College Undergraduate Theses

Cryptography is an ancient art that has passed through many paradigms, from simple letter substitutions to polyalphabetic substitutions to rotor machines to digital encryption to public-key cryptosystems. With the possible advent of quantum computers and the strange behaviors they exhibit, a new paradigm shift in cryptography may be on the horizon. Quantum computers could hold the potential to render most modern encryption useless against a quantum-enabled adversary. The aim of this thesis is to characterize this convergence of cryptography and quantum computation. We provide definitions for cryptographic primitives that frame them in general terms with respect to complexity. We explore …


Three Power-Aware Routing Algorithms For Sensor Networks, Javed Aslam, Qun Li, Daniela Rus Jul 2002

Three Power-Aware Routing Algorithms For Sensor Networks, Javed Aslam, Qun Li, Daniela Rus

Dartmouth Scholarship

This paper discusses online power‐aware routing in large wireless ad hoc networks (especially sensor networks) for applications in which the message sequence is not known. We seek to optimize the lifetime of the network. We show that online power‐aware routing does not have a constant competitive ratio to the off‐line optimal algorithm. We develop an approximation algorithm called max–min zPmin that has a good empirical competitive ratio. To ensure scalability, we introduce a second online algorithm for power‐aware routing. This hierarchical algorithm is called zone‐based routing. Our experiments show that its performance is quite good. Finally, we …