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The Effects Of Singular Value Decomposition On Collaborative Filtering, Michael H. Pryor Jun 1998

The Effects Of Singular Value Decomposition On Collaborative Filtering, Michael H. Pryor

Dartmouth College Undergraduate Theses

As the information on the web increases exponentially, so do the efforts to automatically filter out useless content and to search for interesting content. Through both explicit and implicit actions, users define where their interests lie. Recent efforts have tried to group similar users together in order to better use this data to provide the best overall filtering capabilities to everyone. This thesis discusses ways in which linear algebra, specifically the singular value decomposition, can be used to augment these filtering capabilities to provide better user feedback. The goal is to modify the way users are compared with one another, …


Avoiding Conflicts Dynamically In Direct Mapped Caches With Minimal Hardware Support, Peter N. Desantis Jun 1998

Avoiding Conflicts Dynamically In Direct Mapped Caches With Minimal Hardware Support, Peter N. Desantis

Dartmouth College Undergraduate Theses

The memory system is often the weakest link in the performance of today's computers. Cache design has received increasing attention in recent years as increases in CPU performance continues to outpace decreases in memory latency. Bershad et al. proposed a hardware modification called the Cache Miss Lookaside buffer which attempts to dynamically identify data which is conflicting in the cache and remap pages to avoid future conflicts. In a follow-up paper, Bershad et al. tried to modify this idea to work with standard hardware but had less success than with their dedicated hardware. In this thesis, we focus on a …


Location Independent Names For Nomadic Computers, David Steere, Mark Morrissey, Peter Geib, Calton Pu, Jonathan Walpole Jun 1998

Location Independent Names For Nomadic Computers, David Steere, Mark Morrissey, Peter Geib, Calton Pu, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Recent advances in the Domain Name System (DNS) and the Dynamic Host Configuration Protocol (DHCP) have enabled a new approach to supporting mobile users: location independent naming. In this approach, machines use the same hostname from any internet location, but use an IP address that corresponds to their current location. We describe a protocol that implements location independent naming for nomadic computers, i.e., machines that do not need transparent mobility. Our protocol allows hosts to move across security domains, uses existing protocols, and preserves existing trust relationships. Therefore, it preserves the performance and security of normal IP for nomadic computers …


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 14, Number 6, June 1998, College Of Engineering And Computer Science, Wright State University Jun 1998

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 14, Number 6, June 1998, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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


Parallel Linear Congruential Generators With Prime Moduli, Michael Mascagni Jun 1998

Parallel Linear Congruential Generators With Prime Moduli, Michael Mascagni

Faculty Publications

Linear congruential generators (LCGs) remain the most popular method of pseudorandom number generation on digital computers. Ease of implementation has favored implementing LCGs with power-of-two moduli. However, prime modulus LCGs are superior in quality to power-of-two modulus LCGs, and the use of a Mersenne prime minimizes the computational cost of generation. When implemented for parallel computation, quality becomes an even more compelling issue. We use a full-period exponential sum as the measure of stream independence and present a method for producing provably independent streams of LCGs in parallel by utilizing an explicit parameterization of all of the primitive elements module …


Computational Geometry Column 33, Joseph O'Rourke Jun 1998

Computational Geometry Column 33, Joseph O'Rourke

Computer Science: Faculty Publications

Several recent SIGGRAPH papers on surface simplification are described.


Process Lower Deviation Selection Policy For Load Distribution, Louay Farag Jun 1998

Process Lower Deviation Selection Policy For Load Distribution, Louay Farag

Archived Theses and Dissertations

No abstract provided.


Bond System Security And Access Control Models, Buibing Hao, Ladislau Bölöni, Dan C. Marinescu Jun 1998

Bond System Security And Access Control Models, Buibing Hao, Ladislau Bölöni, Dan C. Marinescu

Department of Computer Science Technical Reports

No abstract provided.


Automated Estimation Of Relaxation For Interface Relaxation, John R. Rice, P. Tsompanopoulou, E. Vavalis Jun 1998

Automated Estimation Of Relaxation For Interface Relaxation, John R. Rice, P. Tsompanopoulou, E. Vavalis

Department of Computer Science Technical Reports

No abstract provided.


Lazy Algorithms In Parallel Discrete Event Simulation, Reuben Pasquini Jun 1998

Lazy Algorithms In Parallel Discrete Event Simulation, Reuben Pasquini

Department of Computer Science Technical Reports

No abstract provided.


Efficient Parallel Algorithms For Planar St-Graphs, Mikhail J. Atallah, Danny Z. Chen, Ovidiu Daescu Jun 1998

Efficient Parallel Algorithms For Planar St-Graphs, Mikhail J. Atallah, Danny Z. Chen, Ovidiu Daescu

Department of Computer Science Technical Reports

No abstract provided.


Empirical Studies Of A Safe Regression Test Selection Technique, Gregg Rothermel, Mary Jean Harrold Jun 1998

Empirical Studies Of A Safe Regression Test Selection Technique, Gregg Rothermel, Mary Jean Harrold

School of Computing: Faculty Publications

Regression testing is an expensive testing procedure utilized to validate modified software. Regression test selection techniques attempt to reduce the cost of regression testing by selecting a subset of a program’s existing test suite. Safe regression test selection techniques select subsets that, under certain well-defined conditions, exclude no tests (from the original test suite) that if executed would reveal faults in the modified software. Many regression test selection techniques, including several safe techniques, have been proposed, but few have been subjected to empirical validation. This paper reports empirical studies on a particular safe regression test selection technique, in which the …


A Measurement Of The Inclusive B → Sγ Branching Ratio, R. Barate, Manoj Thulasidas Jun 1998

A Measurement Of The Inclusive B → Sγ Branching Ratio, R. Barate, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

The avour changing neutral current decay b ! s has been detected in hadronic Z decays collected by ALEPH at LEP. The signal is isolated in lifetime-tagged b b events by the presence of a hard photon associated with a system of high momentum and high rapidity hadrons. The background processes are normalised from the data themselves. The inclusive branching ratio is measured to be (3:11 0:80stat 0:72syst) 104 ; consistent with the Standard Model expectation via penguin processes


Database Selection Techniques For Routing Bibliographic Queries, Ee Peng Lim, Wee-Keong Ng, Jian Xu, Yinyan Cao Jun 1998

Database Selection Techniques For Routing Bibliographic Queries, Ee Peng Lim, Wee-Keong Ng, Jian Xu, Yinyan Cao

Research Collection School Of Computing and Information Systems

No abstract provided.


Singularity Avoidance Strategies For Satellite Mounted Manipulators Using Attitude Control, Nathan A. Titus Jun 1998

Singularity Avoidance Strategies For Satellite Mounted Manipulators Using Attitude Control, Nathan A. Titus

Theses and Dissertations

Control concepts for satellite mounted manipulators (SMM) are examined. The primary focus is on base actuated concepts, which eliminate singularity problems associated with free floating SMMs. A new form of the equations of motion for an n-link SMM is developed using a quasi coordinate form of Lagrange's Equation. Alternative free floating SMM designs are presented which eliminate dynamic singularities, but still experience difficulties due to the unactuated base. A new generic SMM controller is developed as a framework for various control concepts with and without base actuation. Momentum constrained Jacobians are shown to produce better SMM tracking than fixed base …


A Computational Framework For Telemedicine, Ian Foster, Gregor Von Laszewski, Brian Toonen, George K. Thiruvathukal Jun 1998

A Computational Framework For Telemedicine, Ian Foster, Gregor Von Laszewski, Brian Toonen, George K. Thiruvathukal

Computer Science: Faculty Publications and Other Works

Emerging telemedicine applications require the ability to exploit diverse, geographically distributed resources. These applications use high-speed neworks to integrate supercomputers, large databases, archival storage devices, advanced visualization devices, and/or sophisticated instruments. This form of networked virtual supercomputers is also known as metacomputers and is being used by many other scientific applications areas. In this article, we analyze requirements necessary for a telemedicine computing infrastructure and compare them with requirements found in a typical metacomputing environment. We will show that metacomputing environments can be used to enable a more powerful and unified computational infrastructure for telemedicine. The Globus metacomputing environment can …


Querying Structured Web Resources, Ee Peng Lim, Cheng Hai Tan, Boon Wan Lim, Wee-Keong Ng Jun 1998

Querying Structured Web Resources, Ee Peng Lim, Cheng Hai Tan, Boon Wan Lim, Wee-Keong Ng

Research Collection School Of Computing and Information Systems

To provide query facilities over Web resources, several web search engines such as Yahoo, Altavista, Infoseek, etc. have been developed. Most prominently, web search engines have been used to index all web pages on the Internet. The queries supported by these search engines are mainly designed to reveal web pages that meet the search criteria specified by the users. In this way, the search engines have been used as some kind of discovery tools. The queries supported are known as discovery queries. On the other hand, a web search engine can also be used to index and support queries over …


The Intelligent Browser For Texpros, Chih-Ying Wang May 1998

The Intelligent Browser For Texpros, Chih-Ying Wang

Dissertations

Browsing is a technique, which helps users to formulate their query and retrieve information in the information retrieval system. This technique provides users with capabilities of understanding their information needs and gaining system knowledge during the course of the browsing and thus it eases the users' burden when issuing queries. The basic components of the browser provides an underlying structure which allows users to navigate and a browsing process controller which provides users with the needed assistance during each browsing session.

In this dissertation, a new infrastructure (OP-Net), transformed from the existing object network is proposed. Each object in the …


Knowledge-Based Document Filing For Texpros, Xien Fan May 1998

Knowledge-Based Document Filing For Texpros, Xien Fan

Dissertations

This dissertation presents a knowledge-based document filing system for TEXPROS. The requirements of a. personal document processing system are investigated. In order for the system to be used in various application domains, a flexible, dynamic modeling approach is employed by getting the user involved in document modeling. The office documents are described using a dual-model which consists of a document type hierarchy and a folder organization. The document type hierarchy is used to capture the layout, logical and conceptual structures of documents. The folder organization, which is defined by the user, emulates the real world structure for organizing and storing …


Application Of The Internet Technology And Client/Server Paradigm For The Implementation Of Repi, Chetankumar G. Patel May 1998

Application Of The Internet Technology And Client/Server Paradigm For The Implementation Of Repi, Chetankumar G. Patel

Theses

There are many problems associated with Requirements Engineering such as defining the system scope, developing understanding among the communities involved in the system to be built, volatility of requirements etc. These problems may lead to poor requirements and therefore cancellation of the system development, or else the development of a system that is unsatisfactory, has high maintenance cost or is unacceptable. By improving Requirements Elicitation, the Requirements Engineering can be improved, leading to a better requirements specification and eventually a better product.

Requirements Elicitation requires effective communication among the team members, as communication is the key factor. Easing communications between …


Implementation Of A Geometric Hashing Technique And It's Application To 3d Molecular Structure Search, Jennifer Lynn Cerequas May 1998

Implementation Of A Geometric Hashing Technique And It's Application To 3d Molecular Structure Search, Jennifer Lynn Cerequas

Theses

This paper proposes the application of a geometric hash technique to the searching of 3D chemical structures. Chemical structures are represented in global XYZ coordinate format. An algorithm is applied to the substructures within the existing chemical structures to hash them into hash tables on disk. A query substructure is then hashed to find matches (hits) of the existing hash tables. The entries in the matching hash tables are compared to the query substructure to find the existing substructures that are an "approximate" match.

The result is a technique which allows existing substructures to be compared to a (new) query …


Protocols For Packet Switched Communication And Reliable Multicasting In Fully-Dynamic Multi-Hop Wireless Networks, James Pelech May 1998

Protocols For Packet Switched Communication And Reliable Multicasting In Fully-Dynamic Multi-Hop Wireless Networks, James Pelech

Theses

Designing protocols for a fully dynamic wireless packet switched networks pose unique challenges due to the constantly changing topology of the network. A set of protocols is presented that are capable of handling a fully dynamic wireless network in which switching centers and base stations are mobile as well as the end users. The protocols provide basic message delivery, network routing information updates, and support for reliable multicasting.

There are four contributions of this work: (i) a hierarchical architecture for a fully dynamic wireless network, (ii) improved routing and update protocols with reduced control traffic, (iii) a method to provide …


Development Of A Framework For Internet Based Education System, Srinivas Lanka May 1998

Development Of A Framework For Internet Based Education System, Srinivas Lanka

Theses

Development of a framework for Internet based education has demonstrated the use of Oracle tools for the use of delivery of education on the World Wide Web. This also has proved that for an efficient dynamic education scenario, the use of a database-based system with a proper retrieval system is required.

We have designed the system on an Oracle backend system with Designer/2000. Developer/2000 helped us with the design and development of the system. Oracle Web Server 2.1 helped us with the retrieval of the web pages.

The entire design of the system and the reasoning behind the system has …


C Compiler Targeting The Java Virtual Machine, Jack Pien May 1998

C Compiler Targeting The Java Virtual Machine, Jack Pien

Dartmouth College Undergraduate Theses

One of the major drawbacks in the field of computer software development has been the inability for applications to compile once and execute across many different platforms. With the emergence of the Internet and the networking of many different platforms, the Java programming language and the Java Platform was created by Sun Microsystems to address this "Write Once, Run Anywhere" problem. What sets a compiled Java program apart from programs compiled from other high level languages is the ability of a Java Virtual Machine to execute the compiled Java program on any platform, as long as the Java Virtual Machine …


New Algorithms For Moving-Bank Multiple Model Adaptive Estimation, Juan R. Vasquez May 1998

New Algorithms For Moving-Bank Multiple Model Adaptive Estimation, Juan R. Vasquez

Theses and Dissertations

The focus of this research is to provide methods for generating precise parameter estimates in the face of potentially significant parameter variations such as system component failures. The standard Multiple Model Adaptive Estimation (MMAE) algorithm uses a bank of Kalman filters, each based on a different model of the system. A new moving-bank MMAE algorithm is developed based on exploitation of the density data available from the MMAE. The methods used to exploit this information include various measures of the density data and a decision-making logic used to move, expand, and contract the MMAE bank of filters. Parameter discretization within …


Constructing High Order Perceptrons With Genetic Algorithms, Timothy L. Andersen, Tony R. Martinez May 1998

Constructing High Order Perceptrons With Genetic Algorithms, Timothy L. Andersen, Tony R. Martinez

Faculty Publications

Constructive induction, which is defined to be the process of constructing new and useful features from existing ones, has been extensively studied in the literature. Since the number of possible high order features for any given learning problem is exponential in the number of input attributes (where the order of a feature is defined to be the number of attributes of which it is composed), the main problem faced by constructive induction is in selecting which features to use out of this exponentially large set of potential features. For any feature set chosen the desirable characteristics are minimality and generalization …


Optimal Control Using A Neural/Evolutionary Hybrid System, Tony R. Martinez, Dan A. Ventura May 1998

Optimal Control Using A Neural/Evolutionary Hybrid System, Tony R. Martinez, Dan A. Ventura

Faculty Publications

One of the biggest hurdles to developing neurocontrollers is the difficulty in establishing good training data for the neural network. We propose a hybrid approach to the development of neurocontrollers that employs both evolutionary computation (EC) and neural networks (NN). EC is used to discover appropriate control actions for specific plant states. The survivors of the evolutionary process are used to construct a training set for the NN. The NN leams the training set, is able to generalize to new plant states, and is then used for neurocontrol. Thus the EC/NN approach combines the broad, parallel search of EC with …


Quantum Associative Memory With Exponential Capacity, Tony R. Martinez, Dan A. Ventura May 1998

Quantum Associative Memory With Exponential Capacity, Tony R. Martinez, Dan A. Ventura

Faculty Publications

Quantum computation uses microscopic quantum level effects to perrform computational tasks and has produced results that in some cases are exponentially faster than their classical counterparts by taking advantage of quantum parallelism. The unique characteristics of quantum theory may also be used to create a quantum associative memory with a capacity exponential in the number of neurons. This paper covers necessary high-level quantum mechanical ideas and introduces a simple quantum associative memory. Further, it provides discussion, empirical results and directions for future work.


Metamorphic Epiphany -- 3d Animation, Michael G. Corr May 1998

Metamorphic Epiphany -- 3d Animation, Michael G. Corr

Senior Scholar Papers

As far back as I can remember, I have always been interested in studio art. Whether it be painting, drawing, printmaking, or photography, it has consistently been a part of my life. Upon enrolling in Colby, I became interested in computers and decided to major my undergraduate college career in Computer Science. Not forgetting past interests, I continued my studio art education, taking several classes within the Art department. In due time, I began combining interests and began studying Computer Graphics and Design. With limited resources in this field at Colby, the majority of my computer graphic education and experience …


The Dirichlet Problem And Its Physical Motivations, Andrew E. Pitts May 1998

The Dirichlet Problem And Its Physical Motivations, Andrew E. Pitts

Honors Theses

In this work, we explore the basics of harmonic function theory and its relationship to problems in the theory of heat diffusion. In particular, we will focus on the classical Dirichlet problem.