Digital Commons Network^™

Implementing Qos Management For Workflow Systems, Jorge Cardoso, Amit P. Sheth, Krzysztof J. Kochut

Kno.e.sis Publications

Workflow management systems (WfMSs) have been used to support various types of business processes. As organizations adopt new working models, such as e-commerce, new challenges arise for workflow systems. One such challenge is that of quality of service (QoS) management. QoS management includes mechanisms that specify, compute, monitor, and control the quality of service of the products or services to be delivered. A good management of QoS directly impacts the success of organizations participating in e-commerce activities by better fulfilling customer expectations and achieving customer satisfaction. In this paper we present an implementation of a comprehensive QoS model for workflows …

Fast Filter-And-Refine Algorithms For Subsequence Selection, Beng-Chin Ooi, Hwee Hwa Pang, Hao Wang, Limsoon Wong, Cui Yu

Research Collection School Of Computing and Information Systems

Large sequence databases, such as protein, DNA and gene sequences in biology, are becoming increasingly common. An important operation on a sequence database is approximate subsequence matching, where all subsequences that are within some distance from a given query string are retrieved. This paper proposes a filter-and-refine algorithm that enables efficient approximate subsequence matching in large DNA sequence databases. It employs a bitmap indexing structure to condense and encode each data sequence into a shorter index sequence. During query processing, the bitmap index is used to filter out most of the irrelevant subsequences, and false positives are removed in the …

Data Management In Location-Dependent Information Services: Challenges And Issues, Dik Lun Lee, Jianliang Xu, Baihua Zheng, Wang-Chien Lee

Research Collection School Of Computing and Information Systems

Location-dependent information services have great promise for mobile and pervasive computing environments. They can provide local and nonlocal news, weather, and traffic reports as well as directory services. Before they can be implemented on a large scale, however, several research issues must be addressed.

Digital Libraries To Knowledge Portals: Towards A Global Knowledge Portal For Secondary Schools In Singapore, Yin-Leng Theng, Dion Hoe-Lian Goh, Chu Keong Lee, Ee Peng Lim, Zehua Liu

Research Collection School Of Computing and Information Systems

For digital libraries to remain relevant in the new millennium where the ability to manage knowledge is critical, this paper explores how digital libraries could strategically be evolved into knowledge portals to encapsulate knowledge creation, management, sharing and reusability, features evidently lacking in most conventional digital libraries. Two digital library scenarios of use in education are described and implemented as knowledge portals using G-Portal and the Greenstone software. We hope that the initial work carried out on these two portal-like DLs will eventually form part of a Global Knowledge Portal for Secondary Schools in Singapore. Keywords Digital libraries, information portals, …

Machine-Learned Contexts For Linguistic Operations In German Sentence Realization, Eric K. Ringger, Simon Corston-Oliver, Michael Gamon, Robert Moore

Faculty Publications

We show that it is possible to learn the contexts for linguistic operations which map a semantic representation to a surface syntactic tree in sentence realization with high accuracy. We cast the problem of learning the contexts for the linguistic operations as classification tasks, and apply straightforward machine learning techniques, such as decision tree learning. The training data consist of linguistic features extracted from syntactic and semantic representations produced by a linguistic analysis system. The target features are extracted from links to surface syntax trees. Our evidence consists of four examples from the German sentence realization system code-named Amalgam: case …

G-Portal : A Map-Based Digital Library For Distributed Geospatial And Georeferenced Resources, Ee Peng Lim, Dion Hoe-Lian Goh

Research Collection School Of Computing and Information Systems

As the World Wide Web evolves into an immense information network, it is tempting to build new digital library services and expand existing digital library services to make use of web content. In this paper, we present the design and implementation of G-Portal, a web portal that aims to provide digital library services over geospatial and georeferenced content found on the World Wide Web. G-Portal adopts a map-based user interface to visualize and manipulate the distributed geospatial and georeferenced content. Annotation capabilities are supported, allowing users to contribute geospatial and georeferenced objects as well as their associated metadata. The other …

A Digital Library For Geography Examination Resources, Lian-Heong Chua, Dion Hoe-Lian Goh, Zehua Liu, Ee Peng Lim, Rebecca Pei-Hui Ang

Research Collection School Of Computing and Information Systems

We describe a Web-based application developed above a digital library of geographical resources for Singapore students preparing to take a national examination in geography. The application provides an interactive, non-sequential approach to learning that supplements textbooks.

Security Analysis And Improvement Of The Global Key Recovery System, Yanjiang Yang, Feng Bao, Robert H. Deng

Research Collection School Of Computing and Information Systems

Key recovery is a technology that allows the owner of encrypted data or a trusted third party to recover encrypted data, mostly by reconstructing lost decryption key. In [HLG99], Harn et al proposed a Global Key Recovery System (GKRS) that combines the functions of the key recovery authorities and the public key certification authorities (CAs). Among other features, user-dominance, i.e., a user is allowed to select his own public-private key pair and especially a public element for verifying the validity of the public-private key pair, is considered extremely important by [HLG99] for wide acceptance of GKRS. In this paper, we …

Anatomy Of The Coupling Query In A Web Warehouse, Sourav S. Bhowmick, Wee Keong Ng, Sanjay Kumar Madria, Ee Peng Lim

Computer Science Faculty Research & Creative Works

To populate a data warehouse specifically designed for Web data, i.e. web warehouse, it is imperative to harness relevant documents from the Web. In this paper, we describe a query mechanism called coupling query to glean relevant Web data in the context of our web warehousing system called Warehouse of Web Data (WHOWEDA). Coupling query may be used for querying both HTML and XML documents. Some of the important features of our query mechanism are ability to query metadata, content, internal and external (hyperlink) structure of Web documents based on partial knowledge, ability to express constraints on tag attributes and …

Performance And Interoperability In Solar, A Abram White

Dartmouth College Undergraduate Theses

Ubiquitous computing promises to integrate computers into our physical environment, surrounding us with applications that are able to adapt to our dynamics. Solar is a software infrastructure designed to deliver contextual information to these applications. To serve the large number and wide variety of context-aware devices envisioned by ubiquitous computing, Solar must exhibit both high performance and the ability to interoperate with many computing platforms. We created a testing framework to measure the performance of distributed systems such as Solar, as well as a pluggable data-transfer mechanism to support the dissemination of information to heterogeneous applications. This paper explores the …

Testing Homogeneous Spreadsheet Grids With The “What You See Is What You Test” Methodology, Margaret Burnett, Andrei Sheretov, Gregg Rothermel

School of Computing: Faculty Publications

Although there has been recent research into ways to design environments that enable end users to create their own programs, little attention has been given to helping these end users systematically test their programs. To help address this need in spreadsheet systems - the most widely used type of end-user programming language - we previously introduced a visual approach to systematically testing individual cells in spreadsheet systems. However, the previous approach did not scale well in the presence of largely homogeneous grids, which introduce problems somewhat analogous to the array-testing problems of imperative programs. In this paper, we present two …

Dimension And Shape Invariant Programming: The Implementation And Application, Manal Ezzat Helal

Archived Theses and Dissertations

This thesis implements a model for the shape and dimension invariant programming based on the notation of the Mathematics of Arrays (MOA) algebra. It focuses on dimension and shape invariance implementation, and their effect in parallel computing. A new design for the MOA notation is implemented that eliminates the need for another PSI-compiler, or a language extension to functional programming languages. The MOA notation is designed as a library of Application Programming Interfaces (APIs), contains object oriented classes implemented in C++. The library executes array operations correctly, and is expected to enhance the performance invariant of dimension and shape. To …

Modular Machine Learning Methods For Computer-Aided Diagnosis Of Breast Cancer, Mia Kathleen Markey '94

Doctoral Dissertations

The purpose of this study was to improve breast cancer diagnosis by reducing the number of benign biopsies performed. To this end, we investigated modular and ensemble systems of machine learning methods for computer-aided diagnosis (CAD) of breast cancer. A modular system partitions the input space into smaller domains, each of which is handled by a local model. An ensemble system uses multiple models for the same cases and combines the models' predictions.

Five supervised machine learning techniques (LDA, SVM, BP-ANN, CBR, CART) were trained to predict the biopsy outcome from mammographic findings (BIRADS™) and patient age based on a …

Performance Analysis Of A Secure Ieee 802.11b Wireless Network Incorporating Personal Digital Assistants, John L. Camp

Theses and Dissertations

Research results of this thesis indicate very poor performance of a Wireless Local Area Network (WLAN) utilizing PDAs. Network throughput is adversely effected most by VPN implementation and slightly by increased file size. The client distance factor has virtually no effect on the throughput. The impact of each of these factor levels is small when compared to the magnitude of the overall mean throughput (<6%). The average network throughput with the PDA client is much lower than expected (=11,500 bps). This is attributed to several factors with degradation primarily resulting from limitations of the PDA hardware and O/S. Because of the low throughput values achieved (regardless if VPN is on or off), an operational WLAN with PDAs (as tested) is not feasible. Operational use of the network tested would require an in-depth analysis of the type of network traffic and performance required to maintain functionality. To deploy such a system, custom designed Winsock controls would need to be implemented to minimize limitations imposed by the PDA. As PDA technology continues to develop, future hardware and O/S functionality may provide a more robust platform for network communications. The battery life of the PDA and packet battery combination is observed to be about 164 minutes with additional jackets adding about 90 minutes each.

Minimum Energy Paths For Reliable Communication In Multi-Hop Wireless Networks, Suman Banerjee, Archan Misra

Research Collection School Of Computing and Information Systems

Current algorithms for minimum-energy routing in wireless networks typically select minimum-cost multi-hop paths. In scenarios where the transmission power is fixed, each link has the same cost and the minimum-hop path is selected. In situations where the transmission power can be varied with the distance of the link, the link cost is higher for longer hops; the energy-aware routing algorithms select a path with a large number of small-distance hops. In this paper, we argue that such a formulation based solely on the energy spent in a single transmission is misleading --- the proper metric should include the total energy …

Idmp: An Intradomain Mobility Management Protocol For Next-Generation Wireless Networks, Subir Das, Anthony Mcauley, Ashutosh Dutta, Archan Misra, Sajal K. Das

Research Collection School Of Computing and Information Systems

This paper describes a lightweight Intra-domain Management Protocol (IDMP) for managing mobility within a domain, commonly known as micro-mobility management, for next generation wireless networks. IDMP is modular and simple because it leverages existing protocols, such as Mobile IP or SIP (Session Initiated Protocol) as global mobility management, for locating roaming nodes. Unlike other proposed intra-domain mobility management schemes, IDMP uses two dynamically autoconfigured care-of addresses (CoAs) for routing the packets destined to mobile nodes. The global care-of address (GCoA) is relatively stable and identifies the mobile node’s attachment to the current domain, while the local care-of address (LCoA) changes …

Cryptanalysis Of Some Hash Functions Based On Block Ciphers And Codes, Hongjun Wu, Feng Bao, Robert H. 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 alpha*2^m encryptions, where alpha is a small number.

Gscope: A Visualization Tool For Time-Sensitive Software, Ashvin Goel, Jonathan Walpole

Computer Science Faculty Publications and Presentations

This paper describes gscope, a visualization tool for time-sensitive applications. Gscope provides an oscilloscope-like interface that can be integrated with applications. It focuses on software visualization and is thus designed to handle various types of signal waveforms, periodic or event-driven, in single or multithreaded environments as well as local or distributed applications. Gscope helps in visually verifying system correctness and modifying system parameters and thus can complement standard debugging techniques and be used to build compelling software demos. Initial experiments with using gscope show that the library has low overhead.

Development And Characterization Of Methodology And Technology For The Alignment Of Fmri Time Series, Carlo Ciulla

Dissertations

This dissertation has developed, implemented and tested a novel computer based system (AUTOALIGN) that incorporates an algorithm for the alignment of functional Magnetic Resonance Image (fMRI) time series. The algorithm assumes the human brain to be a rigid body and computes a head coordinate system on the basis of three reference points that lie on the directions correspondent to two of the eigenvectors of inertia of the volume, at the intersections with the head boundary. The eigenvectors are found weighting the inertia components with the voxel's intensity values assumed as mass. The three reference points are found in the same …

Collaborative Problem Solving And Program Development Model, Joanna Defranco-Tommarello

Dissertations

A model to enhance collaborative problem solving and program development is presented. The collaborative model is a detailed cognitive model that takes into consideration the cognitive and social activities that occur during collaborative problem solving and program development. The cognitive activities required for collaborative problem solving and program development are identified and integrated into a six-stage model. An extensive literature review in the associated fields is presented to show the need for the model described in this dissertation. In addition, a comprehensive study of tools to support collaboration during problem solving and program development was also performed as well as …

Role Definition Language (Rdl): A Language To Describe Context-Aware Roles, Christopher P. Masone

Dartmouth College Undergraduate Theses

As wireless networks become more prevalent, a widening array of computational resources becomes available to the mobile user. Since not all users should have unrestricted access to these resources, a method of access control must be devised. In a context-aware environment, context information can be used to supplement more conventional password-based access control systems. We believe the best way to achieve this is through the use of Context-Aware Role-Based Access Control, a model in which permissions are assigned to entities called roles, each principal is a member of one or more roles, and a role's membership is determined using context …

Building Trusted Paths For Web Browsers, Zishuang (Eileen) Ye

Dartmouth College Master’s Theses

The communication between the Web browser and the human user is one component of the server-client channel. It is not the user but the browser that receives all server information and establishes the secure connection. The browser's user interface signals, such as SSL lock, https protocol header et al., indicate whether the browser-server communication at the current moment is secure. Those user interface signals indicating the security status of browser should be clearly and correctly understood by the user.

A survey of modern Web browsers shows the information provided by current browsers is insufficient for users to make trust judgment. …

An Evolving Approach To Learning In Problem Solving And Program Development : The Distributed Learning Model, Idania Espinosa

Theses

Technological advances are paving the way for improvements in many sectors of society. The US education system needs to undergo a transformation of existing pedagogical methods to maximize utilization of new technologies. Traditional education has primarily been teacher driven, lectured-based in one location. Advances in technology are challenging existing paradigms by developing tools and educational environments that reach diverse learning styles and surpass the boundaries of current teaching methods.

Distributed learning is an emerging paradigm today that has promise to contribute significantly to learning and improve overall academic success. This research first explores various systems that provide different modes of …

Improving Speech Recognition Learning Through Lazy Training, Tony R. Martinez, Michael E. Rimer, D. Randall Wilson

Faculty Publications

Multi-layer backpropagation, like most learning algorithms that can create complex decision surfaces, is prone to overfitting. We present a novel approach, called lazy training, for reducing the overfit in multiple-layer networks. Lazy training consistently reduces generalization error of optimized neural networks by more than half on a large OCR dataset and on several real world problems from the UCI machine learning database repository. Here, lazy training is shown to be effective in a multi-layered adaptive learning system, reducing the error of an optimized backpropagation network in a speech recognition system by 50.0% on the TIDIGITS corpus.

Network Simplification Through Oracle Learning, Tony R. Martinez, Joshua Menke, Adam Peterson, Michael E. Rimer

Faculty Publications

Often the best artificial neural network to solve a real world problem is relatively complex. However, with the growing popularity of smaller computing devices (handheld computers, cellular telephones, automobile interfaces, etc.), there is a need for simpler models with comparable accuracy. The following research presents evidence that using a larger model as an oracle to train a smaller model on unlabeled data results in 1) a simpler acceptable model and 2) improved results over standard training methods on a similarly sized smaller model. On automated spoken digit recognition, oracle learning resulted in an artificial neural network of half the size …

Comparison Of Inheritance Evaluation Algorithms For Express Edition 3., Judy Dawn Greer

Electronic Theses and Dissertations

Information exchanged between computer applications is difficult, thus the need for data exchange standards. The ISO STEP project defines data exchange standards using the EXPRESS language, which supports inheritance. Currently there are two algorithms used to evaluate an inheritance hierarchy: the Test and Generate algorithms. In this thesis, enhancements are made to both algorithms to support the Total Over Constraint, which is proposed for the third edition of EXPRESS. A formal algorithm is derived for the Test algorithm. The two enhanced algorithms are compared and shown to be result equivalent. However, it is shown that the Test algorithm is the …

Modeling Quality Of Service For Workflows And Web Service Processes, Jorge Cardoso, John A. Miller, Amit P. Sheth, Jonathan Arnold

Kno.e.sis Publications

Workflow management systems (WfMSs) have been used to support various types of business processes for more than a decade now. In workflows for e-commerce and Web-services applications, suppliers and customers define a binding agreement or contract between the two parties, specifying Quality of Service (QoS) items such as products or services to be delivered, deadlines, quality of products, and cost of services. The management of QoS metrics directly impacts the success of organizations participating in e-commerce. Therefore, when services or products are created or managed using workflows, the underlying workflow system must accept the specifications and be able to estimate, …

Analysis Of Protein Sequences Using Time Frequency And Kolmogorov-Smirnov Methods, Kobby Essien

Dartmouth College Undergraduate Theses

The plethora of genomic data currently available has resulted in a search for new algorithms and analysis techniques to interpret genomic data. In this two-fold study we explore techniques for locating critical amino acid residues in protein sequences and for estimating the similarity between proteins. We demonstrate the use of the Short-Time Fourier Transform and the Continuous Wavelet Transform together with amino acid hydrophobicity in locating important amino acid domains in proteins and also show that the Kolmogorov-Smirnov statistic can be used as a metric of protein similarity.

Joining Multiple Data Streams With Window Constraints, Moustafa A. Hammad, Walid G. Aref, Ahmed K. Elmagarmid

Department of Computer Science Technical Reports

No abstract provided.

Supporting Low-Latency Tcp-Based Media Streams, Ashvin Goel, Charles Krasic, Kang Li, Jonathan Walpole

Computer Science Faculty Publications and Presentations

The dominance of the TCP protocol on the Internet and its success in maintaining Internet stability has led to several TCP-based stored media-streaming approaches. The success of these approaches raises the question whether TCP can be used for low-latency streaming. Low latency streaming allows responsive control operations for media streaming and can make interactive applications feasible. We examined adapting the TCP send buffer size based on TCP's congestion window to reduce application perceived network latency. Our results show that this simple idea significantly improves the number of packets that can be delivered within 200 ms and 500 ms thresholds.