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

Digital Commons Network™

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

Computer Sciences

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 17341 - 17370 of 20646

Full-Text Articles in Entire DC Network

Energy-Efficient Group Key Management Protocols For Hierarchical Sensor Networks, Biswajit Panja, Sanjay Kumar Madria, Bharat Bhargava Apr 2007

Energy-Efficient Group Key Management Protocols For Hierarchical Sensor Networks, Biswajit Panja, Sanjay Kumar Madria, Bharat Bhargava

Computer Science Faculty Research & Creative Works

In this paper, we describe a group key management protocol for hierarchical sensor networks where instead of using pre-deployed keys, each sensor node generates a partial key dynamically using a function. The function takes partial keys of its children as arguments. The design of the protocol is motivated by the fact that traditional cryptographic techniques are impractical in sensor networks because of associated high energy and computational overheads. The group key management protocol supports the establishment of two types of group keys; one for the nodes within a group (intra-cluster), and the other among a group of cluster heads (inter-cluster). …

Go to article

Automated Refactoring Of Legacy Java Software To Enumerated Types, Raffi Khatchadourian, Jason Sawin, Atanas Rountev Apr 2007

Automated Refactoring Of Legacy Java Software To Enumerated Types, Raffi Khatchadourian, Jason Sawin, Atanas Rountev

Publications and Research

Modern Java languages introduce several new features that offer significant improvements over older Java technology. In this article we consider the new enum construct, which provides language support for enumerated types. Prior to recent Java languages, programmers needed to employ various patterns (e.g., the weak enum pattern) to compensate for the absence of enumerated types in Java. Unfortunately, these compensation patterns lack several highly-desirable properties of the enum construct, most notably, type safety. We present a novel fully-automated approach for transforming legacy Java code to use the new enumeration construct. This semantics-preserving approach increases type safety, produces code that is …

Go to article

The Quality Of Open Source Production: Zealots And Good Samaritans In The Case Of Wikipedia, Denise Anthony, Sean W. Smith, Tim Williamson Apr 2007

The Quality Of Open Source Production: Zealots And Good Samaritans In The Case Of Wikipedia, Denise Anthony, Sean W. Smith, Tim Williamson

Computer Science Technical Reports

New forms of production based in electronic technology, such as open-source and open-content production, convert private commodities (typically software) into essentially public goods. A number of studies find that, like in other collective goods, incentives for reputation and group identity motivate contributions to open source goods, thereby overcoming the social dilemma inherent in producing such goods. In this paper we examine how contributor motivations affect the quality of contributions to the open-content online encyclopedia Wikipedia. We find that quality is associated with contributor motivations, but in a surprisingly inconsistent way. Registered users' quality increases with more contributions, consistent with the …

Go to article

Diagnosing Reading Strategies: Paraphrase Recognition, Chutima Boonthum Apr 2007

Diagnosing Reading Strategies: Paraphrase Recognition, Chutima Boonthum

Computer Science Theses & Dissertations

Paraphrase recognition is a form of natural language processing used in tutoring, question answering, and information retrieval systems. The context of the present work is an automated reading strategy trainer called iSTART (Interactive Strategy Trainer for Active Reading and Thinking). The ability to recognize the use of paraphrase—a complete, partial, or inaccurate paraphrase; with or without extra information—in the student's input is essential if the trainer is to give appropriate feedback. I analyzed the most common patterns of paraphrase and developed a means of representing the semantic structure of sentences. Paraphrases are recognized by transforming sentences into this representation and …

Go to article

Summarizing Review Scores Of "Unequal" Reviewers, Hady W. Lauw, Ee Peng Lim, Ke Wang Apr 2007

Summarizing Review Scores Of "Unequal" Reviewers, Hady W. Lauw, Ee Peng Lim, Ke Wang

Research Collection School Of Computing and Information Systems

A frequently encountered problem in decision making is the following review problem: review a large number of objects and select a small number of the best ones. An example is selecting conference papers from a large number of submissions. This problem involves two sub-problems: assigning reviewers to each object, and summarizing reviewers ’ scores into an overall score that supposedly reflects the quality of an object. In this paper, we address the score summarization sub-problem for the scenario where a small number of reviewers evaluate each object. Simply averaging the scores may not work as even a single reviewer could …

Go to article

Vulnerability Analysis Of Emap: An Efficient Rfid Mutual Authentication Protocol, Tieyan Li, Robert H. Deng Apr 2007

Vulnerability Analysis Of Emap: An Efficient Rfid Mutual Authentication Protocol, Tieyan Li, Robert H. Deng

Research Collection School Of Computing and Information Systems

In this paper, we analyze the security vulnerabilities of EMAP, an efficient RFID mutual authentication protocol recently proposed by Peris-Lopez et al. (2006). We present two effective attacks, a de-synchronization attack and a full-disclosure attack, against the protocol. The former permanently disables the authentication capability of a RFID tag by destroying synchronization between the tag and the RFID reader. The latter completely compromises a tag by extracting all the secret information stored in the tag. The de-synchronization attack can be carried out in just round of interaction in EMAP while the full-disclosure attack is accomplished across several runs of EMAP. …

Go to article

On-The-Fly Dynamic Dead Variable Analysis, Joel P. Self Mar 2007

On-The-Fly Dynamic Dead Variable Analysis, Joel P. Self

Theses and Dissertations

State explosion in model checking continues to be the primary obstacle to widespread use of software model checking. The large input ranges of variables used in software is the main cause of state explosion. As software grows in size and complexity the problem only becomes worse. As such, model checking research into data abstraction as a way of mitigating state explosion has become more and more important. Data abstractions aim to reduce the effect of large input ranges. This work focuses on a static program analysis technique called dead variable analysis. The goal of dead variable analysis is to discover …

Go to article

Improving Machine Learning Through Oracle Learning, Joshua Ephraim Menke Mar 2007

Improving Machine Learning Through Oracle Learning, Joshua Ephraim Menke

Theses and Dissertations

The following dissertation presents a new paradigm for improving the training of machine learning algorithms, oracle learning. The main idea in oracle learning is that instead of training directly on a set of data, a learning model is trained to approximate a given oracle's behavior on a set of data. This can be beneficial in situations where it is easier to obtain an oracle than it is to use it at application time. It is shown that oracle learning can be applied to more effectively reduce the size of artificial neural networks, to more efficiently take advantage of domain experts …

Go to article

Ria: An Rf Interference Avoidance Algorithm For Heterogeneous Wireless Networks, Daniel P. Delorey, Qiuyi Duan, Charles D. Knutson, Manoj Pandey, Lei Wang, Ryan W. Woodings, Daniel Zappala Mar 2007

Ria: An Rf Interference Avoidance Algorithm For Heterogeneous Wireless Networks, Daniel P. Delorey, Qiuyi Duan, Charles D. Knutson, Manoj Pandey, Lei Wang, Ryan W. Woodings, Daniel Zappala

Faculty Publications

Devices with multiple wireless interfaces are becoming increasingly popular. We envision that these devices will become the building block for future mesh networks, providing seamless connectivity across a range of heterogeneous devices. Although these devices typically implement frequency sharing, using either Direct Sequence Spread Spectrum (DSSS) or Frequency Hopping Spread Spectrum (FHSS), they may still interfere with one another. In this paper we provide a novel Radio Interference Avoidance (RIA) algorithm that solves the problem of interference between IEEE 802.11 and Bluetooth. We then extend this algorithm to other types of DSSS and FHSS combinations. Though the algorithm is limited …

Go to article

Obstacle Annotation By Demonstration, Michael David Clement Mar 2007

Obstacle Annotation By Demonstration, Michael David Clement

Theses and Dissertations

By observing human driving with a “digital head" (combined video camera and accelerometers) and taking a few hand annotations, we can automatically annotate regions in a robot's field of view that should be interpreted as obstacles to be avoided. This is accomplished by detecting the movement for a given frame in a video. Some hand annotations of video frames are necessary and they are used to create Probability Grids. Using the movement data and the Probability Grids, it is possible to annotate large amounts of video data quickly in an automated system.

Go to article

Observational Studies Of Software Engineering Using Data From Software Repositories, Daniel Pierce Delorey Mar 2007

Observational Studies Of Software Engineering Using Data From Software Repositories, Daniel Pierce Delorey

Theses and Dissertations

Data for empirical studies of software engineering can be difficult to obtain. Extrapolations from small controlled experiments to large development environments are tenuous and observation tends to change the behavior of the subjects. In this thesis we propose the use of data gathered from software repositories in observational studies of software engineering. We present tools we have developed to extract data from CVS repositories and the SourceForge Research Archive. We use these tools to gather data from 9,999 Open Source projects. By analyzing these data we are able to provide insights into the structure of Open Source projects. For example, …

Go to article

Stylized Hatching For 3d Animation, Trent Fielding Crow Mar 2007

Stylized Hatching For 3d Animation, Trent Fielding Crow

Theses and Dissertations

Much research has been done in creating non-photorealistic renderings of objects that mimic the look of hand-made drawings by traditional artists. This thesis extends work in this area by presenting an NPR hatching method that can be applied to 3D animated films to help them feel more hand drawn. In contrast to most other NPR methods, this method preserves the 3D lighting and effects of the film that make it interesting to watch. This process includes a procedural algorithm to create a hatching pattern that can be easily integrated into any film's pipeline that uses Renderman. In addition, we create …

Go to article

Locating Encrypted Data Hidden Among Non-Encrypted Data Using Statistical Tools, Walter J. Hayden Mar 2007

Locating Encrypted Data Hidden Among Non-Encrypted Data Using Statistical Tools, Walter J. Hayden

Theses and Dissertations

This research tests the security of software protection techniques that use encryption to protect code segments containing critical algorithm implementation to prevent reverse engineering. Using the National Institute of Standards and Technology (NIST) Tests for Randomness encrypted regions hidden among non-encrypted bits of a binary executable file are located. The location of ciphertext from four encryption algorithms (AES, DES, RSA, and TEA) and three block sizes (10, 100, and 500 32-bit words) were tested during the development of the techniques described in this research. The test files were generated from the Win32 binary executable file of Adobe's Acrobat Reader version …

Go to article

Rely-Guarantee Approach To Reasoning About Aspect-Oriented Programs, Raffi Khatchadourian, Neelam Soundarajan Mar 2007

Rely-Guarantee Approach To Reasoning About Aspect-Oriented Programs, Raffi Khatchadourian, Neelam Soundarajan

Publications and Research

Over the last few years, the question of reasoning about aspect-oriented programs has been addressed by a number of authors. In this paper, we present a rely-guarantee approach to such reasoning. The rely-guarantee approach has proven extremely successful in reasoning about concurrent and distributed programs. We show that some of the key problems encountered in reasoning about aspect-oriented programs are similar to those encountered in reasoning about concurrent programs; and that the rely-guarantee approach, appropriately modified, helps address these problems. We illustrate our approach with a simple example.

Go to article

Experiences With Tracking The Effects Of Changing Requirements On Morphbank: A Web-Based Bioinformatics Application, Subhajit Datta, Robert Van Engelen, David Gaitros, Neelima Jammigumpula Mar 2007

Experiences With Tracking The Effects Of Changing Requirements On Morphbank: A Web-Based Bioinformatics Application, Subhajit Datta, Robert Van Engelen, David Gaitros, Neelima Jammigumpula

Research Collection School Of Computing and Information Systems

In this paper, we present a case study of applying the metrics Mutation Index, Component Set, Dependency Index on Morphbank- a web based bioinformatics application - to track the effects of changing requirements on a software system and suggest design modifications to mitigate such impact. Morphbank is "an open web repository of biological images documenting specimen-based research in comparative anatomy, morphological phylogenetics, taxonomy and related fields focused on increasing our knowledge about biodiversity". This paper discusses the context of the case study, analyzes the results, highlights observations and learning, and mentions directions of future work.

Go to article

Efficient Algorithms For Machine Scheduling Problems With Earliness And Tardiness Penalties, Guang Feng, Hoong Chuin Lau Mar 2007

Efficient Algorithms For Machine Scheduling Problems With Earliness And Tardiness Penalties, Guang Feng, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

In this paper, we study the multi-machine scheduling problem with earliness and tardiness penalties and sequence dependent setup times. This problem can be decomposed into two subproblems—sequencing and timetabling. Sequencing focuses on assigning each job to a fixed machine and determine the job sequence on each machine. We call such assignment a semi-schedule. Timetabling focuses on finding an executable schedule from the semi-schedule via idle-time insertion. Sequencing is strongly NP-hard in general. Although timetabling is polynomial-time solvable, it can become a computational bottleneck if the procedure is executed many times within a larger framework. This paper makes two contributions. We …

Go to article

Malicious Kgc Attacks In Certificateless Cryptography, Man Ho Au, Jing Chen, Joseph K. Liu, Yi Mu, Duncan S. Wong, Guomin Yang, Guomin Yang Mar 2007

Malicious Kgc Attacks In Certificateless Cryptography, Man Ho Au, Jing Chen, Joseph K. Liu, Yi Mu, Duncan S. Wong, Guomin Yang, Guomin Yang

Research Collection School Of Computing and Information Systems

Identity-based cryptosystems have an inherent key escrow issue, that is, the Key Generation Center (KGC) always knows user secret key. If the KGC is malicious, it can always impersonate the user. Certificateless cryptography, introduced by Al-Riyami and Paterson in 2003, is intended to solve this problem. However, in all the previously proposed certificateless schemes, it is always assumed that the malicious KGC starts launching attacks (so-called Type II attacks) only after it has generated a master public/secret key pair honestly. In this paper, we propose new security models that remove this assumption for both certificateless signature and encryption schemes. Under …

Go to article

Valuing Information Technology Infrastructures: A Growth Options Approach, Qizhi Dai, Robert J. Kauffman, Salvatore T. March Mar 2007

Valuing Information Technology Infrastructures: A Growth Options Approach, Qizhi Dai, Robert J. Kauffman, Salvatore T. March

Research Collection School Of Computing and Information Systems

Decisions to invest in information technology (IT) infrastructure are often made based on an assessment of its immediate value to the organization. However, an important source of value comes from the fact that such technologies have the potential to be leveraged in the development of future applications. From a real options perspective, IT infrastructure investments create growth options that can be exercised if and when an organization decides to develop systems to provide new or enhanced IT capabilities. We present an analytical model based on real options that shows the process by which this potential is converted into business value, …

Go to article

Percentage-Based Hybrid Pattern Training With Neural Network Specific Cross Over, Sheng-Uei Guan, Kiruthika Ramanathan Mar 2007

Percentage-Based Hybrid Pattern Training With Neural Network Specific Cross Over, Sheng-Uei Guan, Kiruthika Ramanathan

Research Collection School Of Computing and Information Systems

In this paper, a new weight-setting method is proposed to improve the training time and generalization accuracy of feed-forward neural networks. This method introduces a percentage-based hybrid pattern training (PHP) scheme and aims to provide a solution to the problem dependency of other Genetic Algorithm (GA)-based Neural Network weight-setting methods. A neural network is trained using a neural network specific GA until a certain percentage of the training patterns is learned. The weights thus obtained are used as the initial weights for backpropagation (BP) training, which is then applied to complete the network training. Further improvement to the method was …

Go to article

Analysis Of Routing Worm Infection Rates On An Ipv4 Network, James Gorsuch Mar 2007

Analysis Of Routing Worm Infection Rates On An Ipv4 Network, James Gorsuch

Theses and Dissertations

Malicious logic, specifically worms, has caused monetary expenditure problems to network users in the past. Worms, like Slammer and Code Red, have infected thousands of systems and brought the Internet to a standstill. This research examines the ability of the original Slammer worm, the Slammer based routing worm proposed by Zou et al, and a new Single Slash Eight (SSE) routing worm proposed by this research to infect vulnerable systems within a given address space. This research investigates the Slammer worm's ability to generate a uniform random IP addresses in a given address space. Finally, a comparison of the speed …

Go to article

Privacy-Preserving Credentials Upon Trusted Computing Augmented Servers, Yanjiang Yang, Robert H. Deng, Feng Bao Mar 2007

Privacy-Preserving Credentials Upon Trusted Computing Augmented Servers, Yanjiang Yang, Robert H. Deng, Feng Bao

Research Collection School Of Computing and Information Systems

Credentials are an indispensable means for service access control in electronic commerce. However, regular credentials such as X.509 certificates and SPKI/SDSI certificates do not address user privacy at all, while anonymous credentials that protect user privacy are complex and have compatibility problems with existing PKIs. In this paper we propose privacy-preserving credentials, a concept between regular credentials and anonymous credentials. The privacy-preserving credentials enjoy the advantageous features of both regular credentials and anonymous credentials, and strike a balance between user anonymity and system complexity. We achieve this by employing computer servers equipped with TPMs (Trusted Platform Modules). We present a …

Go to article

Tube (Text-Cube) For Discovering Documentary Evidence Of Associations Among Entities, Hady Lauw, Ee Peng Lim, Hwee Hwa Pang Mar 2007

Tube (Text-Cube) For Discovering Documentary Evidence Of Associations Among Entities, Hady Lauw, Ee Peng Lim, Hwee Hwa Pang

Research Collection School Of Computing and Information Systems

User-driven discovery of associations among entities, and documents that provide evidence for these associations, is an important search task conducted by researchers and do-main information specialists. Entities here refer to real or abstract objects such as people, organizations, ideologies, etc. Associations are the inter-relationships among entities. Most current works in query-driven document retrieval and finding representative subgraphs are ill-suited for the task as they lack an awareness of entity types as well as an intuitive representation of associations. We propose the TUBE model, a text cube approach for discovering associations and documentary evidence of these associations. The model consists of …

Go to article

A Day In The Life Of Pubmed: Analysis Of A Typical Day's Query Log, Jorge R Herskovic, Len Y Tanaka, William Hersh, Elmer V Bernstam Mar 2007

A Day In The Life Of Pubmed: Analysis Of A Typical Day's Query Log, Jorge R Herskovic, Len Y Tanaka, William Hersh, Elmer V Bernstam

Faculty, Staff and Student Publications

OBJECTIVE: To characterize PubMed usage over a typical day and compare it to previous studies of user behavior on Web search engines. DESIGN: We performed a lexical and semantic analysis of 2,689,166 queries issued on PubMed over 24 consecutive hours on a typical day. MEASUREMENTS: We measured the number of queries, number of distinct users, queries per user, terms per query, common terms, Boolean operator use, common phrases, result set size, MeSH categories, used semantic measurements to group queries into sessions, and studied the addition and removal of terms from consecutive queries to gauge search strategies. RESULTS: The size of …

Go to article

Live Surface, Christopher J. Armstrong Feb 2007

Live Surface, Christopher J. Armstrong

Theses and Dissertations

Live Surface allows users to segment and render complex surfaces from 3D image volumes at interactive (sub-second) rates using a novel, Cascading Graph Cut (CGC). Live Surface consists of two phases. (1) Preprocessing for generation of a complete 3D watershed hierarchy followed by tracking of all catchment basin surfaces. (2) User interaction in which, with each mouse movement, the 3D object is selected and rendered in real time. Real-time segmentation is ccomplished by cascading through the 3D watershed hierarchy from the top, applying graph cut successively at each level only to catchment basins bordering the segmented surface from the previous …

Go to article

Small Business Ticketing System, Mohita Kadur Feb 2007

Small Business Ticketing System, Mohita Kadur

Regis University Student Publications (comprehensive collection)

Many small businesses in the cable and Internet industry provide services around cable, Internet and telephone for local residential areas. This is a win-win for both customers and service providers. Customers enjoy localized services and customer support that enables a quick turn around time on problems or outages. In order to efficiently service these customers, a ticketing system would be needed that enables customer identification, issue identification and tracking, provide updates on the status of an issue by technicians. This project is aimed at creating such a solution for a small sized service provider business. The end result of this …

Go to article

Near Real-Time Extract, Transform And Load, Wei-Chwen Soon Wilson Feb 2007

Near Real-Time Extract, Transform And Load, Wei-Chwen Soon Wilson

Regis University Student Publications (comprehensive collection)

The integrated Public Health Information System (iPHIS) system requires a maximum one hour data latency for reporting and analysis. The existing system uses trigger-based replication technology to replicate data from the source database to the reporting database. The data is transformed into materialized views in an hourly full refresh for reporting. This solution is Central Processing Unit (CPU) intensive and is not scaleable. This paper presents the results of a pilot project which demonstrated that near real-time Extract, Transform and Load (ETL), using conventional ETL process with Change Data Capture (CDC), can replace this existing process to improve performance and …

Go to article

Inference Of Node And Edge Replacement Graph Grammars, Jacek Kukluk Feb 2007

Inference Of Node And Edge Replacement Graph Grammars, Jacek Kukluk

Computer Science and Engineering Dissertations - Archive

In this dissertation we study the inference of node and edge replacement graph grammars. The approach is based on previous research in frequent isomorphic subgraphs discovery. We extend the search for frequent subgraphs by checking for overlap among the instances of the subgraphs in the input graph. If subgraphs overlap by one node, we propose a node replacement graph grammar production. If subgraphs overlap by two nodes or two nodes and an edge, we propose an edge replacement graph grammar production. We also can infer a hierarchy of productions by compressing portions of a graph described by a production and …

Go to article

Feature-Based Mini Unmanned Air Vehicle Video Euclidean Stabilization With Local Mosaics, Damon Dyck Gerhardt Feb 2007

Feature-Based Mini Unmanned Air Vehicle Video Euclidean Stabilization With Local Mosaics, Damon Dyck Gerhardt

Theses and Dissertations

Video acquired using a camera mounted on a mini Unmanned Air Vehicle (mUAV) may be very helpful in Wilderness Search and Rescue and many other applications but is commonly plagued with limited spatial and temporal field of views, distractive jittery motions, disorienting rotations, and noisy and distorted images. These problems collectively make it very difficult for human viewers to identify objects of interest as well as infer correct orientations throughout the video. In order to expand the temporal and spatial field of view, stabilize, and better orient users of noisy and distorted mUAV video, a method is proposed of estimating …

Go to article

Human–Robot Interaction: A Survey, Michael A. Goodrich, Alan C. Schultz Feb 2007

Human–Robot Interaction: A Survey, Michael A. Goodrich, Alan C. Schultz

Faculty Publications

Human–Robot Interaction (HRI) has recently received considerable attention in the academic community, in labs, in technology companies, and through the media. Because of this attention, it is desirable to present a survey of HRI to serve as a tutorial to people outside the field and to promote discussion of a unified vision of HRI within the field. The goal of this review is to present a unified treatment of HRI-related problems, to identify key themes, and discuss challenge problems that are likely to shape the field in the near future. Although the review follows a survey structure, the goal of …

Go to article

Interactive Image Repair With Assisted Structure And Texture Completion, Teryl Arnold, Bryan S. Morse Feb 2007

Interactive Image Repair With Assisted Structure And Texture Completion, Teryl Arnold, Bryan S. Morse

Faculty Publications

Removing image defects in an undetectable manner has been studied for its many useful and varied applications. In many cases the desired result may be ambiguous from the image data alone and needs to be guided by a user’s knowledge of the intended result. This paper presents a framework for interactively incorporating user guidance into the filling-in process, more effectively using user input to fill in damaged regions in an image. This framework contains five main steps: first, the scratch or defect is detected; second, the edges outside the defect are detected; third, curves are fit to the detected edges; …

Go to article

First Prev Next Last