Digital Commons Network^™

Finding Constrained Frequent Episodes Using Minimal Occurrences, Xi Ma, Hwee Hwa Pang, Kian-Lee Tan

Research Collection School Of Computing and Information Systems

Recurrent combinations of events within an event sequence, known as episodes, often reveal useful information. Most of the proposed episode mining algorithms adopt an apriori-like approach that generates candidates and then calculates their support levels. Obviously, such an approach is computationally expensive. Moreover, those algorithms are capable of handling only a limited range of constraints. In this paper, we introduce two mining algorithms - episode prefix tree (EPT) and position pairs set (PPS) - based on a prefix-growth approach to overcome the above limitations. Both algorithms push constraints systematically into the mining process. Performance study shows that the proposed algorithms …

Anonymous Secure Routing In Mobile Ad-Hoc Networks, Bo Zhu, Zhiguo Wan, Mohan S. Kankanhalli, Feng Bao, Robert H. Deng

Research Collection School Of Computing and Information Systems

Although there are a large number of papers on secure routing in mobile ad-hoc networks, only a few consider the anonymity issue. In this paper, we define more strict requirements on the anonymity and security properties of the routing protocol, and notice that previous research works only provide Weak Location Privacy and Route Anonymity, and are vulnerable to specific attacks. Therefore, we propose the Anonymous Secure Routing (ASR) protocol that can provide additional properties on anonymity, i.e. Identity Anonymity and Strong Location Privacy, and at the same time ensure the security of discovered routes against various passive and active attacks. …

Problems With The Dartmouth Wireless Snmp Data Collection, Tristan Henderson, David Kotz

Computer Science Technical Reports

The original Dartmouth wireless network study used SNMP to query the college's Cisco 802.11b access points. The perl scripts that performed the SNMP queries suffered from some problems, in that they queried inappropriate SNMP values, or misunderstood the meaning of other values. This data was also used in a subsequent analysis. The same scripts were used to collect data for a subsequent study of another wireless network. This document outlines these problems and indicates which of the data collected by the original scripts may be invalid.

Performance Evaluation Of A Resource Discovery Service, Jue Wang

Dartmouth College Master’s Theses

In a pervasive computing environment, the number and variety of resources (services, devices, and contextual information resources) make it necessary for applications to accurately discover the best ones quickly. Thus a resource-discovery service, which locates specific resources and establishes network connections as better resources become available, is necessary for those applications. The performance of the resource-discovery service is important when the applications are in a dynamic and mobile environment. In this thesis, however, we do not focus on the resource- discovery technology itself, but the evaluation of the scalability and mobility of the resource discovery module in Solar, a context …

Semantic Web Technology In Support Of Bioinformatics For Glycan Expression, Amit P. Sheth, William S. York, Christopher Thomas, Meenakshi Nagarajan, John A. Miller, Krzysztof Kochut, Satya S. Sahoo, Xiaochuan Yi

Kno.e.sis Publications

Due to the complexity of biological systems, interpretation of data obtained by a single experimental approach can often be interpreted only if viewed from a broader context, taking into account the information obtained by many diverse techniques. The vast amount of interpreted experimental data that is now available via the internet opens the possibility of collecting the relevant pieces of information that will enable scientists to form hypotheses based on the integration of this diverse information. However, the sheer volume of data that is available makes it very difficult to select the information necessary to make a coherent model of …

Computational Approaches To The Design And Analysis Of Stability Of Polypeptide Multilayer Thin Films, Bin Zheng

Doctoral Dissertations

The focus of this research is the development of computational approaches to understanding the physical basis of layer-by-layer assembly (LBL), a key methodology of nanomanufacturing. The results provided detailed information on structure which cannot be obtained directly by experiments.

The model systems chosen for study are polypeptide chains. Reasons for this are that polypeptides are no less polyelectrolytes than the more usual polyions, and one can control the primary structure of a polypeptide on a residue-by-residue basis using modern synthetic methods. Moreover, as peptides constitute one of the four major classes of biological macromolecules, research in this direction is expected …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 21, Number 2, October 2004, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Airconn: A Framework For Tiered Services In Public Wireless Lan Hot Spots, A. Acharya, C. Bisdikian, Archan Misra, Y. Ko

Research Collection School Of Computing and Information Systems

Access to the data services via wireless LANs at private and public hot spot sites is becoming commonplace. The goal of the airConn project is to define an architecture and a prototype implementation that enable the provision of premium and non-premium service tiers for both transient and nontransient users of wireless hot spots. airConn provides for dynamic renegotiation of service tiers and facilitates various billing modes. Thus, it enables service providers to increase their revenue opportunities via multiple flexibility manageable service offerings.

Comments On "A Practical (T, N) Threshold Proxy Signature Scheme Based On The Rsa Cryptosystem", Guilin Wang, Feng Bao, Jianying Zhou, Robert H. Deng

Research Collection School Of Computing and Information Systems

In a (t, n) threshold proxy signature scheme based on RSA, any t or more proxy signers can cooperatively generate a proxy signature while t-1 or fewer of them can't do it. The threshold proxy signature scheme uses the RSA cryptosystem to generate the private and the public key of the signers. In this article, we discuss the implementation and comparison of some threshold proxy signature schemes that are based on the RSA cryptosystem. Comparison is done on the basis of time complexity, space complexity and communication overhead. We compare the performance of four schemes: Hwang et al., Wen et …

A Survey Of Online E-Banking Retail Initiatives, P. Southard, Keng Siau

Research Collection School Of Computing and Information Systems

Customer demand is forcing banks to provide their services online. There are two successful paths they can take: to grow, or to specialize in providing localized services and information.

Lsdis: Large Scale Distributed Information Systems Lab, Amit P. Sheth

Kno.e.sis Publications

The LSDIS (Large Scale Distributed Information Systems) lab was established in 1994 with the guidance and direction provided by Dr. Amit P. Sheth with the help of Dr. John A. Miller and Dr. Krzysztof J. Kochut. In 1998 this faculty group was further strengthened by the addition of Dr. Ismailcem B. Arpinar. LSDIS is the largest research group in Computer Science at UGA and one of the strongest in its area. During Fall 2004, it is funding 15 students (majority of them PhD), and has one research staff.

Over the years LSDIS has been actively involved in research projects in …

Cs 409/609: Principles Of Artificial Intelligence, Michael T. Cox

Computer Science & Engineering Syllabi

"Principles of Artificial Intelligence" is a graduate/undergraduate level introductory course in Artificial Intelligence (AI), designed for students interested in or specializing in AL We will cover several basic topics ranging from knowledge representation, inference, problem solving, search, the predicate calculus and other fundamentals of AI, to selected topics concerning intelligent agents, natural language processing, planning, learning, and case-based reasoning. The intent of the course is to provide a background in artificial intelligence, an exposure to the major issues and methods in the field, and experience in writing AI programs. The course will also examine real AI systems and allow the …

Cs 780: Compiler Design And Construction I, Krishnaprasad Thirunarayan

Computer Science & Engineering Syllabi

This course deals with the theory and practice of compiler design. Topics emphasized are scanning and parsing. If time permits, semantic analysis will also be covered.

Ceg 498: Design Experience, John C. Gallagher

Computer Science & Engineering Syllabi

CEG 498 (Design Experience) is a summative computer engineering design project course that builds upon previous engineering, science, mathematics and communications course work. CEG 498 projects are a minim um of two quarters in length and must be completed in groups of at least three students. Projects are selected under the guidance of the course instructor and are tailored to both student interest and formal classroom preparation. Students are evaluated both on their individual contributions as recorded in a graded engineering journals and on the quality of their collective efforts as reflected in group generated products.

Cs 480/680: Comparative Languages, Michael T. Cox

Computer Science & Engineering Syllabi

"Comparative Languages" is a graduate/undergraduate level introductory course in programming languages. We will cover several basic topics ranging from syntax (BNF) and semantics formalisms (attribute grammars), to data types, scope and extent, type checking, parameter passing methods, expression parsing and other fundamentals of programming languages and language development. The intent of the course is to provide a background in the concepts and constructs of languages, rather than simply providing just a survey of various computer languages. Nonetheless in this class, we will learn and program in three very different languages: Pascal (an imperative language), Java (an object-oriented language), and LISP …

Deadline Analysis Of Interrupt-Driven Software, Dennis Brylow, Jens Palsberg

Mathematics, Statistics and Computer Science Faculty Research and Publications

Real-time, reactive, and embedded systems are increasingly used throughout society (e.g., flight control, railway signaling, vehicle management, medical devices, and many others). For real-time, interrupt-driven software, timely interrupt handling is part of correctness. It is vital for software verification in such systems to check that all specified deadlines for interrupt handling are met. Such verification is a daunting task because of the large number of different possible interrupt arrival scenarios. For example, for a Z86-based microcontroller, there can be up to six interrupt sources and each interrupt can arrive during any clock cycle. Verification of such systems has traditionally relied …

Bottleneck Analysis Of Cports, Sreekalyana Chakravarthy Kajuluri

Electrical & Computer Engineering Theses & Dissertations

CPortS is a transportation logistics simulation that models the flow of military cargo through a seaport and the interaction of the cargo with the port resources and infrastructure. It provides information about the seaport's capabilities, how the cargo has been handled, how many days the cargo took to clear a particular port area, and the overall throughput of the seaport. The model is highly data intensive since it models the huge traffic in a real seaport.

Bottlenecks reduce system performance. Systems that are traffic intensive or simulations of systems, which are data intensive, encounter bottlenecks, which reduce their performance. In …

Blocking Reduction Strategies In Hierarchical Text Classification, Ee Peng Lim, Aixin Sun, Wee-Keong Ng, Jaideep Srivastava

Research Collection School Of Computing and Information Systems

One common approach in hierarchical text classification involves associating classifiers with nodes in the category tree and classifying text documents in a top-down manner. Classification methods using this top-down approach can scale well and cope with changes to the category trees. However, all these methods suffer from blocking which refers to documents wrongly rejected by the classifiers at higher-levels and cannot be passed to the classifiers at lower-levels. We propose a classifier-centric performance measure known as blocking factor to determine the extent of the blocking. Three methods are proposed to address the blocking problem, namely, threshold reduction, restricted voting, and …

Compliant Encryption Of Jpeg2000 Codestreams, Yongdong Wu, Robert H. Deng

Research Collection School Of Computing and Information Systems

This paper presents a compliant encryption method for JPEG 2000 codestreams such that the encryption process does not introduce superfluous JPEG2000 markers in the protected codestream, i.e., the protected codestream preserves the syntax of the original codestream. The proposed encryption method works with any standard ciphers, incurs no storage overhead, introduces negligible computational cost and maintains all the desirable properties of the original JPEG 2000 codestream such as error resilience and scalability.

Flexible Verification Of Mpeg-4 Stream In Peer-To-Peer Cdn, Tieyan Li, Yongdong Wu, Di Ma, Robert H. Deng

Research Collection School Of Computing and Information Systems

The current packet based stream authentication schemes provide effective and efficient authentication over a group of packets transmitted on erasure channels. However, by fixing the packets in transmission, any packet manipulation will cause authentication failure. In p2p content delivery network where a proxy-in-the-middle is able to store, forward, transcode and transform the stream, previous schemes are simply unapplicable. To address the problem, we propose a flexible verification scheme that relies on special stream formats (i.e. Unequal Loss Protection ULP scheme [7]). We apply the so called Unequal Loss Verification ULV scheme into MPEG-4 framework. The encoding, packing, amortizing and verifying …

Trust Establishment In Large Scale Grid Settings, Bo Zhu, Tieyan Li, Huafei Zhu, Mohan S . Kankanhalli, Feng Bao, Robert H. Deng

Research Collection School Of Computing and Information Systems

Trust establishment is hard in grid architecture by the ad hoc nature. To set up trust in large scale of network is more difficult. In this paper, we propose an automatic key management (AKM) model and corresponding key construction schemes. The hierarchical structure is formed automatically and scale seamlessly in arbitrary network sized. Regions are configured differently according to various levels of risks faced. The novel model provides an integrated solution for self-organized trust establishment, upon which rich appliances are securely supported. It is automatic, flexible, and scalable. Furthermore, simulation results show that computation costs due to the variations are …

A Novel Log-Based Relevance Feedback Technique In Content-Based Image Retrieval, Steven C. H. Hoi, Michael R. Lyu

Research Collection School Of Computing and Information Systems

Relevance feedback has been proposed as an important technique to boost the retrieval performance in content-based image retrieval (CBIR). However, since there exists a semantic gap between low-level features and high-level semantic concepts in CBIR, typical relevance feedback techniques need to perform a lot of rounds of feedback for achieving satisfactory results. These procedures are time-consuming and may make the users bored in the retrieval tasks. For a long-term study purpose in CBIR, we notice that the users' feedback logs can be available and employed for helping the retrieval tasks in CBIR systems. In this paper, we propose a novel …

Network-Layer Selective Security, Casey T. Deccio

Theses and Dissertations

The Internet and other large computer networks have become an integral part of numerous daily processes. Security at the network layer is necessary to maintain infrastructure survivability in the case of cyber attacks aimed at routing protocols. In order to minimize undesired overhead associated with added security at this level, the notion of selective security is proposed. This thesis identifies elements in network topologies that are most important to the survivability of the network. The results show that the strategic placement of network security at critical elements will improve overall network survivability without the necessity of universal deployment.

Techniques And Patterns For Safe And Efficient Real-Time Middleware, Angelo Corsaro

All Computer Science and Engineering Research

Over 90 percent of all microprocessors are now used for real-time and embedded applications. The behavior of these applications is often constrained by the physical world. It is therefore important to devise higher-level languages and middleware that meet conventional functional requirements, as well as dependably and productively enforce real-time constraints. Real-Time Java is emerging as a safe, real-time environment. In this thesis we use it as our experimentation platform; however, our findings are easily adapted to other similar platforms. This thesis provides the following contributions to the study of safe and efficient real-time middleware. First, it identifies potential bottlenecks and …

Proceedings Of The 2004 Onr Decision-Support Workshop Series: Interoperability, Collaborative Agent Design Research Center

Collaborative Agent Design (CAD) Research Center

In August of 1998 the Collaborative Agent Design Research Center (CADRC) of the California Polytechnic State University in San Luis Obispo (Cal Poly), approached Dr. Phillip Abraham of the Office of Naval Research (ONR) with the proposal for an annual workshop focusing on emerging concepts in decision-support systems for military applications. The proposal was considered timely by the ONR Logistics Program Office for at least two reasons. First, rapid advances in information systems technology over the past decade had produced distributed collaborative computer-assistance capabilities with profound potential for providing meaningful support to military decision makers. Indeed, some systems based on …

Databases For Interval Probabilities, Wenzhong Zhao, Alex Dekhtyar, Judy Goldsmith

Computer Science and Software Engineering

We present a database framework for the efficient storage and manipulation of interval probability distributions and their associated information. Although work on interval probabilities and on probabilistic databases has appeared before, ours is the first to combine these into a coherent and mathematically sound framework including both standard relational queries and queries based on probability theory. In particular, our query algebra allows users not only to query existing interval probability distributions, but also to construct new ones by means of conditionalization and marginalization, as well as other more common database operations.

Utilizing Learning Styles For Interactive Tutorials, Magnus Aase, Franz J. Kurfess

Computer Science and Software Engineering

Developing successful Web-based learning environments has shown to be a challenging and difficult endeavor [7][11] that requires knowledge from multiple domains like pedagogy, psychology, knowledge engineering, software engineering, and Web technologies. Their lack of individual preferred ways of instruction is a challenge we address in this paper. We introduce a Web-based learning environment that teaches concepts from Artificial Intelligence to college students. This environment is intended to be used as a complementary tool for the standard lectures. By adapting the instruction and learning material to the individual student’s learning style the tutorial gives the student a personal learning experience and …

Logic Programs, Iterated Function Systems, And Recurrent Radial Basis Function Networks, Sebastian Bader, Pascal Hitzler

Computer Science and Engineering Faculty Publications

Graphs of the single-step operator for first-order logic programs—displayed in the real plane—exhibit self-similar structures known from topological dynamics, i.e., they appear to be fractals, or more precisely, attractors of iterated function systems. We show that this observation can be made mathematically precise. In particular, we give conditions which ensure that those graphs coincide with attractors of suitably chosen iterated function systems, and conditions which allow the approximation of such graphs by iterated function systems or by fractal interpolation. Since iterated function systems can easily be encoded using recurrent radial basis function networks, we eventually obtain connectionist systems which …

Possible Worlds Semantics For Probabilistic Logic Programs, Alex Dekhtyar, Michael I. Dekhtyar

Computer Science and Software Engineering

In this paper we consider a logic programming framework for rea-soning about imprecise probabilities. In particular, we propose a new semantics, for the Probabilistic Logic Programs (p-programs) of Ng and Subrahmanian. P-programs represent imprecision using probability intervals. Our semantics, based on the possible worlds semantics, considers all point probability distributions that satisfy a given p-program. In the paper, we provide the exact characterization of such models of a p-program. We show that the set of models of a p-program can-not, in general case, be described by single intervals associated with atoms of the program. We provide algorithms for efficient construction …

Helping Analysts Trace Requirements: An Objective Look, Jane Huffman Hayes, Alex Dekhtyar, Senthil Karthikeyan Sundaram, Sarah Howard

Computer Science and Software Engineering

This paper addresses the issues related to improving the overall quality of the requirements tracing process for Independent Verification and Validation analysts. The contribution of the paper is three-fold: we define requirements for a tracing tool based on analyst responsibilities in the tracing process; we introduce several new measures for validating that the requirements have been satisfied; and we present a prototype tool that we built, RETRO (REquirements TRacing On-target), to address these requirements. We also present the results of a study used to assess RETRO’s support of requirements and requirement elements that can be measured objectively.