Digital Commons Network^™

Efficient Detection Of Unusual Words, Alberto Apostolico, Mary Ellen Bock, Stefano Lonardi

Department of Computer Science Technical Reports

No abstract provided.

E-Device: An Extensible Knowledge Base System With Multiple Rule Support, Nick Bassiliades, Ioannis Vlahavas, Ahmed Elmagarmid

Department of Computer Science Technical Reports

No abstract provided.

Modeling And Comparison Of Wormhole Routed Mesh And Torus Networks, Ronald I. Greenberg, Lee Guan

Computer Science: Faculty Publications and Other Works

2D-mesh and torus networks have often been proposed as the interconnection pattern for parallel computers. In addition, wormhole routing has increasingly been advocated as a method of reducing latency. Most analysis of wormhole routed networks, however, has focused on the torus and the broader class of k-ary n-cubes to which it belongs. This paper presents a performance model for the wormhole routed mesh, and it compares the performance of the mesh and torus based on theoretical and empirical analyses.

Formal Specification Of Fragmentation And Reassembly In Ipv6, Ibrahim Sahin

Electrical & Computer Engineering Theses & Dissertations

Development and implementation of a networking standard such as the new Internet Protocol (IPv6) is a very difficult process. Different implementations of the standard must be fully compatible to allow different computers to communicate with each other. However, standards are often ambiguous, frequently a result of providing specifications in the English language. A more formal specification could assist in the design of systems. This thesis demonstrates that capability using the Prototype Verification System (PVS).

In this thesis study, a formal specification for fragmentation and reassembly in IPv6 was created to provide a tool for the standardization of IPv6 using PVS. …

Search For The Standard Model Higgs Boson In E+E- Collisions At √S = 161, 170 And 172 Gev, Barate, R.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

The reaction e+ e ! HZ is used to search for the Standard Model Higgs boson. The data sample consists of integrated luminosities of 10:9 pb1 , 1:1 pb1 , and 9:5 pb1 collected by the ALEPH experiment at LEP during 1996, at centre-of-mass energies of 161, 170 and 172 GeV, respectively. No candidate events were found, in agreement with the expected background of 0.84 events from all Standard Model processes. This search results in a 95% C.L. lower limit on the Higgs boson mass of 69:4 GeV=c2 . When combined with earlier ALEPH searches performed at energies at and …

Extracting Functionally Equivalent Object-Oriented Designs From Legacy Imperative Code, Ricky E. Sward

Theses and Dissertations

This research defines a methodology for automatically extracting functionally equivalent object-oriented designs from legacy imperative programs. The Parameter-Based Object Identification (PBOI) methodology is based on fundamental ideas that relate programs written in imperative languages such as C or COBOL to objects and classes written in object-oriented languages such as Ada 95 or C ++. Transformations have been developed that formalize the PBOI methodology and a formal proof is provided showing the extracted object-oriented design is functionally equivalent to the legacy imperative system. To focus the task of re-engineering, generic models of imperative programming languages and object-oriented programming languages have been …

Distributed Collaborative Learning Environments, Mark C. Kilby

Link Foundation Modeling, Simulation and Training Fellowship Reports

The evolution of technologies for the World Wide Web (WWW), computer-supported cooperative work (CSCW) and distributed simulation provides new opportunities for education delivery as well as unique perspectives for training. Simulation follows a learn-by-doing philosophy . The WWW and CSCW provides a collaborative learning perspective by encouraging collective knowledge building. By merging these two approaches, Distributed Collaborative Learning Environments (DCLEs) can be developed to provide new approaches to training in the military, industry, and academia. Traditional approaches toward educational rely on an information transfer model. Instructors deliver the material to the students and students are tested on how well they …

A Measurement Of The Qcd Colour Factors And A Limit On The Light Gluino, Barate, R.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

Using data collected from 1992 to 1995 with the ALEPH detector at LEP, a measurement of the colour factor ratios CA/CF and TF /CF and the strong coupling constant αs = CFαs(MZ)/(2π) has been performed by fitting theoretical predictions simultaneously to the measured differential two-jet rate and angular distributions in four-jet events. The result is found to be in excellent agreement with QCD, {fx4-1} Fixing CA/CF and TF/CF to the QCD values permits a determination of αs(MZ) and ηf, the number of active flavours. With this measurement the existence of a gluino with mass below 6.3 GeV/c2 is excluded at …

Generating, Visualizing And Evaluating High Quality Clusters For Information Organization, Javed Aslam, Katya Pelekhov, Daniela Rus

Computer Science Technical Reports

We present and analyze the star clustering algorithm. We discuss an implementation of this algorithm that supports browsing and document retrieval through information organization. We define three parameters for evaluating a clustering algorithm to measure the topic separation and topic aggregation achieved by the algorithm. In the absence of benchmarks, we present a method for randomly generating clustering data. Data from our user study shows evidence that the star algorithm is effective for organizing information.

The Self-Organizing Desk, Daniela Rus, Peter De Santis

Dartmouth Scholarship

The self-organizing desk is a system that enhances a physical desk-top with electronic information. It can remember, organize, update, and manipulate the information contained in the documents on a desk. The system consists of a simple robot eye that can survey the desk, a module for smart extraction of information from the images taken by the robot, a module for representing this information in multiple views, and a module that allows a user to interact with this information.

Fast Discrete Polynomial Transforms With Applications To Data Analysis For Distance Transitive Graphs, J. R. Driscoll, D. M. Healy, D. N. Rockmore

Dartmouth Scholarship

Let $\poly = \{P_0,\dots,P_{n-1}\}$ denote a set of polynomials with complex coefficients. Let $\pts = \{z_0,\dots,z_{n-1}\}\subset \cplx$ denote any set of {\it sample points}. For any $f = (f_0,\dots,f_{n-1}) \in \cplx^n$, the {\it discrete polynomial transform} of f (with respect to $\poly$ and $\pts$) is defined as the collection of sums, $\{\fhat(P_0),\dots,\fhat(P_{n-1})\}$, where $\fhat(P_j) = \langle f,P_j \rangle = \sum_{i=0}^{n-1} f_iP_j(z_i)w(i)$ for some associated weight function w. These sorts of transforms find important applications in areas such as medical imaging and signal processing.

In this paper, we present fast algorithms for computing discrete orthogonal polynomial transforms. For a system …

Using Expert Support And Its Explanation Facilities For Group Decision Making, Fiona Fui-Hoon Nah, Izak Benbasat

Research Collection School Of Computing and Information Systems

As information technology is increasingly used to support group work, it becomes desirable to identify the types of computer-based decision aids that are beneficial for supporting group decision making. In a review of the decision support literature, Benbasat, DeSanctis and Nault (1993) point out the lack of empirical research in examining the use of expert support for group decision making. In our review of the literature in this respect, we identified only one case study (Sviokla, 1989), which examined the processes involved in the pre- and post-use of an expert support system (ESS) called PlanPower by a group of financial …

Influence And Consensus In Group Decision Making Environment, Fiona Fui-Hoon Nah, Byungcho Kim

Research Collection School Of Computing and Information Systems

In this research, the effect of expert support on influence and consensus in group decision making is investigated. The results indicate that ESS support diminishes the group members' influence on the group judgment as well as the influence exerted by the most influential group member. On the other hand, explanations support provided by ESS increases consensus in group decision making.

Building Multi-Discipline, Multi-Format Digital Libraries Using Clusters And Buckets, Michael L. Nelson

Computer Science Theses & Dissertations

Our objective was to study the feasibility of extending the Dienst protocol to enable a multi-discipline, multi-format digital library. We implemented two new technologies: cluster functionality and publishing buckets. We have designed a possible implementation of clusters and buckets, and have prototyped some aspects of the resultant digital library.

Currently, digital libraries are segregated by the disciplines they serve ( computer science, aeronautics, etc.), and by the format of their holdings (reports, software, datasets, etc.). NCSTRL+ is a multi-discipline, multi-format digital library (DL) prototype created to explore the feasibility of the design and implementation issues involved with created a …

Learning Recursive Functions From Approximations, John Case, Susanne Kaufmann, Martin Kummer, Efim Kinber

School of Computer Science & Engineering Faculty Publications

This article investigates algorithmic learning, in the limit, of correct programs for recursive functionsffrom both input/output examples offand several interesting varieties ofapproximateadditional (algorithmic) information aboutf. Specifically considered, as such approximate additional information aboutf, are Rose's frequency computations forfand several natural generalizations from the literature, each generalization involving programs for restricted trees of recursive functions which havefas a branch. Considered as the types of trees are those with bounded variation, bounded width, and bounded rank. For the case of learning final correct programs for recursive functions, EX-learning, …

An Improved Analytical Model For Wormhole Routed Networks With Application To Butterfly Fat-Trees, Ronald I. Greenberg, Lee Guan

Computer Science: Faculty Publications and Other Works

A performance model for wormhole routed interconnection networks is presented and applied to the butterfly fat-tree network. Experimental results agree very closely over a wide range of load rate. Novel aspects of the model, leading to accurate and simple performance predictions, include (1) use of multiple-server queues, and (2) a general method of correcting queuing results based on Poisson arrivals to apply to wormhole routing. These ideas can also be applied to other networks.

Multiple Representation For Understanding Data Structures, Biffah Hancies, Venky Shankararaman, Jose Munoz

Research Collection School Of Computing and Information Systems

In this paper an approach to enhance the learning of abstract computing concepts by novice students is presented. This approach is based on effective use of multiple visual representations, and it was applied within the domain of linear data structures: array, stack, queue and linked list. A prototype computer-based instructional system called MRUDS (Multiple Representation for Understanding Data Structures) was developed and evaluated. It was found from the evaluation that the three presentation modules namely, analogy, representation and algorithm contributed to the students' learning process, each contributing to and reinforcing the effect of the others.

Time-Efficient Maze Routing Algorithms On Reconfigurable Mesh Architectures, Fikret Ercal, H. C. Lee

Computer Science Faculty Research & Creative Works

The routing problem is one of the most widely studied problems in VLSI design. Maze-routing algorithms are used in VLSI routing and robot path planning. Efficiency of the parallel maze routing algorithms which were mostly based on C. Y. Lee's algorithm8is poor. In this paper, we propose time-efficient algorithms to solve the maze-routing problem on a reconfigurable mesh architecture. The constant-time algorithms presented include: (i) testing the existence of specific types of paths between two terminals, and (ii) finding an absolute shortest path (ASP) and a shortest duplex-path (SDP). In addition, a fast algorithm to find the single shortest path …

Multimedia Data Analysis Using Imagetcl (Extended Version), Charles B. Owen, Fillia Makedon

Computer Science Technical Reports

ImageTcl is an new system which provides powerful Tcl/Tk based media scripting capabilities similar to those of the ViewSystem and Rivl in a unique environment that allows rapid prototyping and development of new components in the C++ language. Powerful user tools automate the creation of new components as well as the addition of new data types and file formats. Applications using ImageTcl at the Dartmouth Experimental Visualization Laboratory (DEVLAB) include multiple stream media data analysis, automatic image annotation, and image sequence motion analysis. ImageTcl combines the high speed of compiled languages with the testing and parameterization advantages of scripting languages.

Multiple Media Stream Data Analysis: Theory And Applications (Extended Version), Charles B. Owen, Fillia Makedon

Computer Science Technical Reports

This paper presents a new model for multiple media stream data analysis as well as descriptions of some applications of this model in development at Dartmouth College. This model formalizes the exploitation of correlations between multiple, potentially heterogeneous, media streams in support of numerous application areas. The goal of the technique is to determine temporal and spatial alignments which optimize a correlation function and indicate commonality and synchronization between media streams. It also provides a framework for comparison of media in unrelated domains. Applications such as text-to-speech alignment, functional magnetic resonance imaging, speaker localization, and degraded media realignment are described.

Mail Server Installation And Integration, Tim Lewis

Honors Capstone Projects and Theses

No abstract provided.

A Synthesized Methodology For Eliciting Expert Judgment For Addressing Uncertainty In Decision Analysis, Richard W. Monroe

Engineering Management & Systems Engineering Theses & Dissertations

This dissertation describes the development, refinement, and demonstration of an expert judgment elicitation methodology. The methodology has been developed by synthesizing the literature across several social science and scientific fields. The foremost consideration in the methodology development has been to incorporate elements that are based on reasonable expectations for the human capabilities of the user, the expert in this case.

Many methodologies exist for eliciting assessments for uncertain events. These are frequently elicited in probability form. This methodology differs by incorporating a qualitative element as a beginning step for the elicitation process. The qualitative assessment is a more reasonable way …

General Pattern Matching, Alberto Apostolico

Department of Computer Science Technical Reports

No abstract provided.

Afec: An Adaptive Forward Error- Correction Protocol And Its Analysis, Kihong Park

Department of Computer Science Technical Reports

No abstract provided.

Report On The 5th Ifip International Workshop On Quality Of Service, Oguz Angin, Andrew T. Campbell, Lai Tee Cheok, Raymond Liao, Koon-Seng Lim, Klara Nahrstedt

Research Collection School Of Computing and Information Systems

This paper presents a summary of the fifth International Workshop on Quality of Service (IWQOS) which was held at Columbia University in May 1997. The goal of this three-day meeting was to foster interaction between researchers active in the area of Quality of Service(QOS) research, to reflect on past experiences and lessons learnt, and to discuss future QOS challenges. To reflect this goal, this year's workshop included a hot program made up of (i) a keynote address on "Programming Telecommunications Networks"; (ii) panels addressing "QOS for Distributed Object Computing Middleware --- Fact or Fiction?" and "Reservations about Reservations"; (iii) a …

Specification And Verification Of Generic Cell Rate Algorithms In Pvs, Huseyin Ozgungor

Electrical & Computer Engineering Theses & Dissertations

Formal verification methods have been considered as a powerful complementary approach to define standards and to prove correctness of the systems. In this work, formal specification of Generic Cell Rate Algorithms are defined and proved. The specification process enables standardization for constructing Generic Cell Rate Algorithms. Standardization is an important process in the Asynchronous Transfer Mode (ATM) networks. By employing formal methods, the necessary standards could be constructed to allow different algorithms to be employed which still meet system requirements. Those system requirements are quantified in the Quality of Service (QOS).

Congestion management is a vital concept for networks in …

Dynamic Load Distribution In Mist, K. Al-Saqabi, R. M. Prouty, Dylan Mcnamee, Steve Otto, Jonathan Walpole

Computer Science Faculty Publications and Presentations

This paper presents an algorithm for scheduling parallel applications in large-scale, multiuser, heterogeneous distributed systems. The approach is primarily targeted at systems that harvest idle cycles in general-purpose workstation networks, but is also applicable to clustered computer systems and massively parallel processors. The algorithm handles unequal processor capacities, multiple architecture types and dynamic variations in the number of processes and available processors. Scheduling decisions are driven by the desire to minimize turnaround time while maintaining fairness among competing applications. For efficiency, the virtual processors (VPs) of each application are gang scheduled on some subset of the available physical processors.

Measurement Of The Transverse Spin Correlations In The Decay Z → Τ+Τ-, Barate, R.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

A measurement of the transverse-transverse, CTT, and transverse-normal CTN, τ spin correlations in the decay Z0 → τ+ τ− is presented based on the aplanarity angle of the decay products of both taus. Based on 80 pb−1 of data collected by ALEPH[1] in 1992, 1993 and 1994 on the peak of the Z resonance, the results are: CTT = 1.00 ± 0.14(stat) ± 0.04(syst), CTN =−0.08 ± 0.14(stat) ± 0.02(syst). These values are in agreement with the Standard Model predictions, CTT = 0.989 and CTN = 0.

Agent Tcl: A Flexible And Secure Mobile-Agent System, Robert S. Gray

Dartmouth College Ph.D Dissertations

A mobile agent is an autonomous program that can migrate under its own control from machine to machine in a heterogeneous network. In other words, the program can suspend its execution at an arbitrary point, transport itself to another machine, and then resume execution from the point of suspension. Mobile agents have the potential to provide a {\em single, general framework} in which a wide range of distributed applications can be implemented efficiently and easily. Several challenges must be faced, however, most notably reducing migration overhead, protecting a machine from malicious agents (and an agent from malicious machines), and insulating …

Link/Loop/Node Networks, Mark E. Gilbert

Honors Theses

This document is really two separate documents that have been appended together. The first is Link/Loop/Node Networks. This document describes the theory behind link/loop/node networks (LLN), as well as the basic operating instructions for the LLN Simulator (LLNS). The second document is LLN Simulator Technical Reference. This second document describes how the LLNS was constructed using Microsoft Access 2.0, as well as how the LLNS simulates LLN.