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Evaluation Of High Performance Fortran Through Application Kernels, Hon W. Yau, Geoffrey C. Fox, Ken Hawick Jan 1997

Evaluation Of High Performance Fortran Through Application Kernels, Hon W. Yau, Geoffrey C. Fox, Ken Hawick

Northeast Parallel Architecture Center

Since the definition of the High Performance Fortran (HPF) standard, we have been maintaining a suite of application kernel codes with the aim of using them to evaluate the available compilers. This paper presents the results and conclusions from this study, for sixteen codes, on compilers from IBM, DEC, and the Portland Group Inc. (PGI), and on three machines: a DEC Alphafarm, an IBM SP-2, and a Cray T3D. From this, we hope to show the prospective HPF user that scalable performance is possible with modest effort, yet also where the current weaknesses lay.


The Hadamard Matroid And An Anomaly In Its Single Element Extensions, C. H. Cooke Jan 1997

The Hadamard Matroid And An Anomaly In Its Single Element Extensions, C. H. Cooke

Mathematics & Statistics Faculty Publications

A nonstandard vector space is formulated, whose bases afford a representation of what is called a Hadamard matroid, Mp. For prime p, existence of Mp is equivalent to the existence of both a classical Hadamard matrix H(p,p) and a certain affine resolvable, balanced incomplete block design AR(p). An anomaly in the representable single element extension of a Hadamard matroid is discussed.


Expert System For The Generation Of A Work Breakdown Structure, Bernard O'Callaghan Jan 1997

Expert System For The Generation Of A Work Breakdown Structure, Bernard O'Callaghan

Theses

This thesis outlines research work carried out in the Mechanical & Manufacturing Department in Cork Regional Technical College, Ireland. With computers now having an increasingly dominant role in all areas of business, it was inevitable that computer-based project management packages would become more popular. To date however, these packages have concentrated on monitoring and controlling projects. The definition and brainstorming phases required to generate a project plan are still largely manual tasks. Planning a project initially involves generating a complete and organised list of all the tasks needing to be completed in order to achieve a project’s goal. This list …


Review Of Personal Identification Systems, J. M. Cross Jan 1997

Review Of Personal Identification Systems, J. M. Cross

Research outputs pre 2011

The growth of the use of biometric personal identification systems has been relatively steady over the last 20 years. The expected biometric revolution which was forecast since the mid 1970's has not yet occurred. The main factor for lower than expected growth has been the cost and user acceptance of the systems. During the last few years, however, a new generation of more reliable, less expensive and better designed biometric devices have come onto the market. This combined with the anticipated expansion of new reliable, user friendly inexpensive systems provides a signal that the revolution is about to begin. This …


Faster Ray Tracing Using Adaptive Grids, Thomas W. Sederberg, Krysztof S. Klimaszewski Jan 1997

Faster Ray Tracing Using Adaptive Grids, Thomas W. Sederberg, Krysztof S. Klimaszewski

Faculty Publications

A new hybrid approach is presented which outperforms the regular grid technique in scenes with highly irregular object distributions by a factor of hundreds, and combined with an area interpolator, by a factor of thousands. Much has been said about scene independence of different acceleration techniques and the alleged superiority of one approach over another. Several theoretical and practical studies conducted in the past have led to the same conclusion: a space partitioning method that allows the fastest rendering of one scene often fails with another. Specialization may be the answer. This has always been pursued, consciously or not, in …


Keyboardless Visual Programming Using Voice, Handwriting, And Gesture, Jennifer Leopold, A. Ambler Jan 1997

Keyboardless Visual Programming Using Voice, Handwriting, And Gesture, Jennifer Leopold, A. Ambler

Computer Science Faculty Research & Creative Works

Visual programming languages have facilitated the application development process, improving our ability to express programs, as well as our ability to view, edit and interact with them. Yet even in programming environments, productivity is restricted by the primary input sources: the mouse and the keyboard. As an alternative, we investigate a program development interface which responds to the most natural human communication technologies: voice, handwriting and gesture. Speech- and pen-based systems have yet to find broad acceptance in everyday life because they are insufficiently advantageous to overcome problems with reliability. However, we believe that a visual programming environment with a …


Timestamp-Based Approach For The Detection And Resolution Of Mutual Conflicts In Distributed Systems, Sanjay Kumar Madria Jan 1997

Timestamp-Based Approach For The Detection And Resolution Of Mutual Conflicts In Distributed Systems, Sanjay Kumar Madria

Computer Science Faculty Research & Creative Works

We present a timestamp based algorithm for the detection of both write-write and read-write conflicts for a single file in distributed systems during network partitions. Our algorithm allows operations to occur in different network partitions simultaneously. When the sites from different partitions merge, the algorithm detects and resolves both read-write and write-write conflicts without taking into account the semantics of the transactions. Once the conflicts have been detected some reconciliation steps for the resolution of conflicts have also been proposed. Our algorithm will be useful in real-time systems where timeliness of operations is more important than response time (delayed commit)


Measurement Of The Spectral Functions Of Vector Current Hadronic Tau Decays, R. Barate, M. Thulasidas Jan 1997

Measurement Of The Spectral Functions Of Vector Current Hadronic Tau Decays, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

A measurement of the spectral functions of non-strange τ vector current final states is presented, using 124 358 τ pairs recorded by the ALEPH detector at LEP during the years 1991 to 1994. The spectral functions of the dominant two- and four-pion τ decay channels are compared to published results of e + e - annihilation experiments via isospin rotation. A combined fit of the pion form factor from τ decays and e + e - data is performed using different parametrizations. The mass and the width of the ρ ±(770) and the ρ 0(770) are separately determined in order …


Improved Measurement Of The Bd0 -B̄D0 Oscillation Frequency, D. Buskulic, M. Thulasidas Jan 1997

Improved Measurement Of The Bd0 -B̄D0 Oscillation Frequency, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

The time dependence of B0 d {B 0 d oscillations is measured by the ALEPH experiment at LEP, using three techniques, two of which are updates of previous measurements. In all cases the charge of the decaying b quark and its decay time are measured in one hemisphere of the event; the quark charge at production is tagged mainly using the opposite hemisphere. The first method uses the charge correlation between a D and a lepton in the opposite hemisphere; if no lepton is present, the produced quark charge is determined from the hemisphere charges. In the second method, the …


Measurement Of The Τ Lepton Lifetime With The Three-Dimensional Impact Parameter Method, R. Barate, M. Thulasidas Jan 1997

Measurement Of The Τ Lepton Lifetime With The Three-Dimensional Impact Parameter Method, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

A new method is presented for the measurement of the mean lepton lifetime using events in which are pair-produced and both's decay to hadrons.


Transverse Momentum Correlations In Hadronic Z Decays, D. Buskulic, M. Thulasidas Jan 1997

Transverse Momentum Correlations In Hadronic Z Decays, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

Using data obtained with the ALEPH detector at the Z resonance, a measure based on transverse momentum is shown to exhibit a correlation between the two halves of a hadronic event which cannot be explained by energy-momentum conservation, flavour conservation, the imposition of an event axis or imperfect event reconstruction. Two possible interpretations based on existing Monte Carlo models are examined: a) ARIADNE, with the correlation forming early in the parton shower and with the transition from partons to hadrons playing only a minor part; b) JETSET, with the correlation forming at the fragmentation stage. A correlation technique based on …


The Topology Dependence Of Charged Particle Multiplicities In Three-Jet Events, R. Barate, M. Thulasidas Jan 1997

The Topology Dependence Of Charged Particle Multiplicities In Three-Jet Events, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

A study of individual jet and whole-event charged particle multiplicities in three-jet events measured in e + e − annihilation at the Z reveals a significant topology dependence. Mean jet multiplicities are inadequately described by jet energies; interjet angles must also be specified. Quantitative tests suggest that it is necessary to use transversemomentum- like scales to describe the data.


Computer-Aided Mechanical Assembly Design Using Configuration Spaces, Leo Joskowicz, Elisha Sacks Jan 1997

Computer-Aided Mechanical Assembly Design Using Configuration Spaces, Leo Joskowicz, Elisha Sacks

Department of Computer Science Technical Reports

No abstract provided.


Financial Prediction And Trading Strategies Using Neurofuzzy Approaches, K. N. Pantazopoulos, L. H. Tsoukalas, N. G. Bourbakis, M. J. Brün, Elias N. Houstis Jan 1997

Financial Prediction And Trading Strategies Using Neurofuzzy Approaches, K. N. Pantazopoulos, L. H. Tsoukalas, N. G. Bourbakis, M. J. Brün, Elias N. Houstis

Department of Computer Science Technical Reports

No abstract provided.


Future Scientific Software Systems, John R. Rice Jan 1997

Future Scientific Software Systems, John R. Rice

Department of Computer Science Technical Reports

No abstract provided.


Interface Relaxation Methods For Elliptic Differential Equations, John R. Rice, P. Tsompanopoulou, E. Vavalis Jan 1997

Interface Relaxation Methods For Elliptic Differential Equations, John R. Rice, P. Tsompanopoulou, E. Vavalis

Department of Computer Science Technical Reports

No abstract provided.


Examining Locally Varying Weights For Nearest Neighbor Algorithms, Nicholas Howe, Claire Cardie Jan 1997

Examining Locally Varying Weights For Nearest Neighbor Algorithms, Nicholas Howe, Claire Cardie

Computer Science: Faculty Publications

Previous work on feature weighting for case-based learning algorithms has tended to use either global weights or weights that vary over extremely local regions of the case space. This paper examines the use of coarsely local weighting schemes, where feature weights are allowed to vary but are identical for groups or clusters of cases. We present a new technique, called class distribution weighting (CDW), that allows weights to vary at the class level. We further extend CDW into a family of related techniques that exhibit varying degrees of locality, from global to local. The class distribution techniques are then applied …


Hardware Interfacing In The Broadcast Industry Using Simple Network Management Protocol (Snmp), Walter H. Schuller Jr. Jan 1997

Hardware Interfacing In The Broadcast Industry Using Simple Network Management Protocol (Snmp), Walter H. Schuller Jr.

UNF Graduate Theses and Dissertations

Communication between various broadcast equipment plays a major role in the daily operation of a typical broadcast facility. For example, editing equipment must interface with tape machines, production switchers must interface with font generators and video effect equipment, and satellite ground controllers must interface with satellite dishes and receivers. Communication between these devices may be a simple hardware handshake configuration or a more elaborate software based communications via serial or parallel interfacing. This thesis concerns itself with the software interfacing needed to allow various dissimilar types of equipment to communicate, and therefore, interface with each other. The use of Simple …


Analysis Of Digital Logic Schematics Using Image Recognition, James A. Giles Jan 1997

Analysis Of Digital Logic Schematics Using Image Recognition, James A. Giles

UNF Graduate Theses and Dissertations

This thesis presents the results of research in the area of automated recognition of digital logic schematics. The adaptation of a number of existing image processing techniques for use with this kind of image is discussed, and the concept of using sets of tokens to represent the overall drawing i s explained in detail. Methods are given for using tokens to describe schematic component shapes, to represent the connections between components, and to provide sufficient information to a parser so that an equation can be generated. A Microsoft Windows-based test program which runs under Windows 95 or Windows NT has …


User Defined Prewrites For Increasing Concurrency In Design Databases, Sanjay Kumar Madria, A. Embong Jan 1997

User Defined Prewrites For Increasing Concurrency In Design Databases, Sanjay Kumar Madria, A. Embong

Computer Science Faculty Research & Creative Works

We introduce a prewrite operation before a write operation is performed on design databases, a database that consists of objects as engineering designs. A prewrite operation does not actually make a design but it only makes available the model of the design that the transaction will produce in future. Once the prewrite design by a transaction is announced, the transaction executes a pre-commit operation. After the pre-commit, read operations can access the prewrite design even before the pre-committed transaction has finally made the design and committed. Therefore, our algorithm increases the potential concurrency as compared to the algorithms that permit …


A Concurrency Control Algorithm For An Open And Safe Nested Transaction Model, Sanjay Kumar Madria Jan 1997

A Concurrency Control Algorithm For An Open And Safe Nested Transaction Model, Sanjay Kumar Madria

Computer Science Faculty Research & Creative Works

We present a concurrency control algorithm for an open and safe nested transaction model. We use prewrite operations in our model to increase the concurrency. Prewrite operations are modeled as subtransactions in the nested transaction tree. The subtransaction which initiates prewrite subtransactions are modelled as recovery point subtransaction. The recovery point subtransaction can release their locks before its ancestors commit. Thus, our model increases the concurrency in comparison to other nested transaction models. Our model is useful an environment of long-running transactions common in object oriented databases, computer aided design and in the software development process


Rmesh Algorithms For Parallel String Matching, Hsi-Chieh Lee, Fikret Erçal Jan 1997

Rmesh Algorithms For Parallel String Matching, Hsi-Chieh Lee, Fikret Erçal

Computer Science Faculty Research & Creative Works

String matching problem received much attention over the years due to its importance in various applications such as text/file comparison, DNA sequencing, search engines, and spelling correction. Especially with the introduction of search engines dealing with tremendous amount of textual information presented on the world wide web and the research on DNA sequencing, this problem deserves special attention and any algorithmic or hardware improvements to speed up the process will benefit these important applications. In this paper, we present three algorithms for string matching on reconfigurable mesh architectures. Given a text T of length n and a pattern P of …


Evolutionary Computation Applied To Adaptive Information Filtering, Daniel R. Tauritz, Ida G. Sprinkhuizen-Kuyper, Joost N. Kok Jan 1997

Evolutionary Computation Applied To Adaptive Information Filtering, Daniel R. Tauritz, Ida G. Sprinkhuizen-Kuyper, Joost N. Kok

Computer Science Faculty Research & Creative Works

Information Filtering is concerned with filtering data streams in such a way as to leave only pertinent data (information) to be perused. When the data streams are produced in a changing environment the filtering has to adapt too in order to remain effective. Adaptive Information Filtering is concerned with filtering in changing environments. The changes may occur both on the transmission side (the nature of the streams can change), and on the reception side (the interest of a user can change). Weighted trigram analysis is a quick and flexible technique for describing the contents of a document. A novel application …


Operation And Control In A Competitive Market: Distributed Generation In A Restructured Industry, Judith Cardell, Richard Tabors Jan 1997

Operation And Control In A Competitive Market: Distributed Generation In A Restructured Industry, Judith Cardell, Richard Tabors

Engineering: Faculty Publications

The prospect of independent ownership for distributed technologies is being encouraged by the current deregulation of the industry, and it is possible that the new generators will be independently operated as well as independently owned. The siting of numerous small-scale generators in distribution feeders is likely to have an impact on the operations and control of the power system, a system designed to operate with large, central generating facilities. In response to the new and potentially conflicting economic and technical demands of a growing number of independent players, the power system may require new means for coordinating system operations. Price …


Time-Optimal Tree Computations On Sparse Meshes, D. Bhagavathi, V. Bokka, H. Gurla, S. Olariu, J. L. Schwing Jan 1997

Time-Optimal Tree Computations On Sparse Meshes, D. Bhagavathi, V. Bokka, H. Gurla, S. Olariu, J. L. Schwing

Computer Science Faculty Publications

The main goal of this work is to fathom the suitability of the mesh with multiple broadcasting architecture (MMB) for some tree-related computations. We view our contribution at two levels: on the one hand, we exhibit time lower bounds for a number of tree-related problems on the MMB. On the other hand, we show that these lower bounds are tight by exhibiting time-optimal tree algorithms on the MMB. Specifically, we show that the task of encoding and/or decoding n-node binary and ordered trees cannot be solved faster than Ω(log n) time even if the MMB has an infinite …


Webassess, Justin Anthony Brown Jan 1997

Webassess, Justin Anthony Brown

Theses : Honours

This project and research has resulted in the development of a World Wide Web (WWW) based testing system. WEBassess can be accessed and used from any point in the world that has a connection to the WWW. The WEBassess system allows for the creation and completion of tests through the WWW interface. Scoring and feedback of submitted tests is completely automated, allowing students to see their test result immediately, including visual indicators for correct and incorrect answers. These test results may then be viewed by academic staff, showing complete test details, such as unit code, test title, score, percentage, date …


Does Good Project Management Ensure Successful Software Development?, Julie Lisa Eldridge Jan 1997

Does Good Project Management Ensure Successful Software Development?, Julie Lisa Eldridge

Theses : Honours

For many years the development of computer software has been plagued by poor customer satisfaction caused by missed schedules, underestimated budgets and the development of products which do not meet requirements. The ever increasing reliance on computers, as reported by Sommerville ''the result of the proliferation of computer systems into all aspects of life and business is that personal, corporate, national and international economies are [becoming] increasingly dependant on computers and software systems" ( 1992, p.2), calls for more stable software which can be developed within time and budget constraints. To achieve this, software development activities must be analysed and …


Microlanguages For Operating System Specialization, Calton Pu, Andrew P. Black, Crispin Cowan, Jonathan Walpole, Charles Consel Jan 1997

Microlanguages For Operating System Specialization, Calton Pu, Andrew P. Black, Crispin Cowan, Jonathan Walpole, Charles Consel

Computer Science Faculty Publications and Presentations

Specialization is a technique that has the potential to provide operating system clients with the performance and functionality that they need, while still retaining the advantages of a simple generic code base for the operating system maintainer. However, at present the specialization process is labor-intensive and requires the knowledge of an expert in the domain of application behavior. In order to realize the full advantages of specialization, we believe that the process must be automated. This means building tools for specialization, and also making the domain knowledge explicit in some form or other. A specialization toolkit has been developed jointly …


A Migratable User-Level Process Package For Pvm, Ravi Kunuru, Steve Otto, Jonathan Walpole Jan 1997

A Migratable User-Level Process Package For Pvm, Ravi Kunuru, Steve Otto, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Shared, multi-user, workstation networks are characterized by unpredictable variability in system load. Further, the concept of workstation ownership is typically present. For efficient and unobtrusive computing in such environments, applications must not only overlap their computation with communication but also redistribute their computations adaptively based on changes in workstation availability and load. Managing these issues at application level leads to programs that are difficult to write and debug. In this paper, we present a system that manages this dynamic multi-processor environment while exporting a simple message-based programming model of a dedicated, distributed memory multiprocessor to applications. Programmers are thus insulated …


Curriculum Development And Evaluation For A Computer Literacy Course, Molly J. Fagan Jan 1997

Curriculum Development And Evaluation For A Computer Literacy Course, Molly J. Fagan

Dissertations and Theses @ UNI

This paper describes a curriculum that was developed and used for a computer literacy course at the University of Northern Iowa. The curriculum included a unit of computer programming, which has not been included as part of the computer literacy course in recent years at the University of Northern Iowa. Surveys were given at the beginning of the semester to determine the approximate level of students' prior knowledge. The same survey was given at the end of the semester and the results of both were compared to see how much more comfortable each individual student felt using the various computer …