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Compiling Fortran 90d/Hpf For Distributed Memory Mimd Computers, Zeki Bozkus, Alok Choudhary, Geoffrey C. Fox, Tomasz Haupt Jan 1994

Compiling Fortran 90d/Hpf For Distributed Memory Mimd Computers, Zeki Bozkus, Alok Choudhary, Geoffrey C. Fox, Tomasz Haupt

Northeast Parallel Architecture Center

This paper describes the design of the Fortran90D/HPF compiler, a source-to-source parallel compiler for distributed memory systems being developed at Syracuse University. Fortran 90D/HPF is a data parallel language with special directives to specify data alignment and distributions. A systematic methodology to process distribution directives of Fortran 90D/HPF is presented. Furthermore, techniques for data and computation partitioning, communication detection and generation, and the run-time support for the compiler are discussed. Finally, initial performance results for the compiler are presented. We believe that the methodology to process data distribution, computation partitioning, communication system design and the overall compiler design can be …


Mapping Algorithms And Software Environment For Data Parallel, Nikos Chrisochoides, Elias Houstis, John Rice Jan 1994

Mapping Algorithms And Software Environment For Data Parallel, Nikos Chrisochoides, Elias Houstis, John Rice

Northeast Parallel Architecture Center

We consider computations associated with data parallel iterative solvers used for the numerical solution of Partial Differential Equations (PDEs). The mapping of such computations into load balanced tasks requiring minimum synchronization and communication is a difficult combinatorial optimization problem. Its optimal solution is essential for the efficient parallel processing of PDE computations. Determining data mappings that optimize a number of criteria, like workload balance, synchronization and local communication, often involves the solution of an NP-Complete problem. Although data mapping algorithms have been known for a few years there is lack of qualitative and quantitative comparisons based on the actual performance …


Runtime Array Redistribution In Hpf Programs, Rajeev Thakur, Alok Choudhary, Geoffrey C. Fox Jan 1994

Runtime Array Redistribution In Hpf Programs, Rajeev Thakur, Alok Choudhary, Geoffrey C. Fox

Northeast Parallel Architecture Center

This paper describes efficient algorithms for runtime array redistribution in HPF programs. We consider block(m) to cyclic, cyclic to block(m) and the general cyclic(x) to cyclic(y) type redistributions. We initially describe algorithms for one-dimensional arrays and then extend the methodology to multidimensional arrays. The algorithms are practical enough to be easily implemented in the runtime library of an HPF compiler and can also be directly used in application programs requiring redistribution. Performance results on the Intel Paragon are discussed.


Analysis Of Random Number Generators Using Monte Carlo Simulation, Paul D. Coddington Jan 1994

Analysis Of Random Number Generators Using Monte Carlo Simulation, Paul D. Coddington

Northeast Parallel Architecture Center

Monte Carlo simulation is one of the main applications involving the use of random number generators. It is also one of the best methods of testing the randomness properties of such generators, by comparing results of simulations using different generators with each other, or with analytic results. Here we compare the performance of some popular random number generators by high precision Monte Carlo simulation of the 2-d Ising model, for which exact results are known, using the Metropolis, Swendsen-Wang, and Wolff Monte Carlo algorithms. Many widely used generators that perform well in standard statistical tests are shown to fail these …


Supporting Irregular Distributions In Fortran 90d/Hpf Compilers, Ravi Ponnusamy, Yuan-Shin Hwang, Raja Das, Joel Saltz Jan 1994

Supporting Irregular Distributions In Fortran 90d/Hpf Compilers, Ravi Ponnusamy, Yuan-Shin Hwang, Raja Das, Joel Saltz

Northeast Parallel Architecture Center

This paper presents methods that make it possible to efficiently support irregular problems using data parallel languages. The approach involves the use of a portable, compiler-independent, runtime support library called CHAOS. The CHAOS runtime support library contains procedures that (1) support static and dynamic distributed array partitioning, (2) partition loop iterations and indirection arrays, (3) remap arrays from one distribution to another, and (4) carry out index translation, buffer allocation and communication schedule generation. The CHAOS runtime procedures are used by a prototype Fortran 90D compiler as runtime support for irregular problems. This paper also presents performance results of compiler-generated …


The Design And Evolution Of Zipcode, Anthony Skjellum, Steven G. Smith, Nathan E. Doss, Alvin Leung Jan 1994

The Design And Evolution Of Zipcode, Anthony Skjellum, Steven G. Smith, Nathan E. Doss, Alvin Leung

Northeast Parallel Architecture Center

Zipcode is a message-passing and process-management system that was designed for multicomputers and homogeneous networks of computers in order to support libraries and large-scale multicomputer software. The system has evolved significantly over the last five years, based on our experiences and identified needs. Features of Zipcode that were originally unique to it, were its simultaneous support of static process groups, communication contexts, and virtual topologies, forming the "mailer" data structure. Point-to-point and collective operations reference the underlying group, and use contexts to avoid mixing up messages. Recently, we have added "gather-send" and "receive-scatter" semantics, based on persistent Zipcode "invoices," both …


A Communication System For High-Performance Distributed Computing, Salim Hariri, Jongbaek Park, Manish Parashar, Geoffrey C. Fox Jan 1994

A Communication System For High-Performance Distributed Computing, Salim Hariri, Jongbaek Park, Manish Parashar, Geoffrey C. Fox

Northeast Parallel Architecture Center

With the current advances in computer and networking technology coupled with the availability of software tools for parallel and distributed computing, there has been increased interests in high-performance distributed computing (HPDC). We envision that HPDC environments with supercomputing capabilities will be available in the near future. However, a number of issues have to be resolved before future network-based applications can exploit fully the potential of HPDC environment. In this paper, we present an architecture of a high-speed local area network and a communication system that provides HPDC applications with high bandwidth and low latency. We also characterize the message-passing primitives …


Developing Interactive Pvm-Based Parallel Programs On Distributed Computing Systems Within Avs Framework, Gang Cheng, Geoffrey C. Fox, Kim Mills, Marek Podgorny Jan 1994

Developing Interactive Pvm-Based Parallel Programs On Distributed Computing Systems Within Avs Framework, Gang Cheng, Geoffrey C. Fox, Kim Mills, Marek Podgorny

Northeast Parallel Architecture Center

We discuss techniques in developing interactive Parallel Virtual Machine (PVM) concurrent programs on distributed systems under AVS framework. Using a stock option price modeling application as a case study, we demonstrate a simple, effective and modular approach to coupling network-based concurrent modules into an interactive remote visualization environment. A prototype simulation on-demand system is developed, in which parallel option pricing models locally implemented on two distributed systems, an Ethernet-connected IBM SP1 and a FDDI-based GIGswitch-connected DEC Alpha farm, are coupled with an interactive graphical user interface over a ATM-based wide area network. This integrated networking/visualization framework allows one to use …


Involvement Of Industry In The National High Performance Computing And Communication Enterprise, Geoffrey C. Fox Jan 1994

Involvement Of Industry In The National High Performance Computing And Communication Enterprise, Geoffrey C. Fox

Northeast Parallel Architecture Center

We discuss aspects of a national computer science agenda for High Performance Computing and Communications (HPCC). We agree with the general direction and emphasis of the current program. In particular, the strong experimental component and linkage of applications with computer science should be continued. We recommend accelerating the emphasis on "national challenges " with more applications and technologies from the information, as compared to simulation areas. We suggest modifying the grand challenge concept to complement the current teaming of particular computer science and applications researchers. We would emphasize better linking of each application group to the entire (inter) national computer …


A Study Of Software Development For High Performance Computing, Manish Parashar, Salim Hariri, Tomasz Haupt, Geoffrey C. Fox Jan 1994

A Study Of Software Development For High Performance Computing, Manish Parashar, Salim Hariri, Tomasz Haupt, Geoffrey C. Fox

Northeast Parallel Architecture Center

Software development in a High Performance Computing (HPC) environment is non-trivial and requires a thorough understanding of the application and the architecture. The objective of this paper is to study the software development process in a high performance computing environment and to outline the stages typically encountered in this process. Support required at each stage is also highlighted. The modeling of stock option pricing is used as a running example in the study.


Developing Modular Application Builders To Exploit Mimd Parallel Resources, C. Thornborrow, C. Faigle Jan 1994

Developing Modular Application Builders To Exploit Mimd Parallel Resources, C. Thornborrow, C. Faigle

Northeast Parallel Architecture Center

Modular application builders (MABs), such as AVS and Iris Explorer[6, 7] are increasingly being used in the visualisation community. Such systems can already place compute intensive modules on supercomputers in order to utilise their power. This paper details two major projects at EPCC which attempted to fully integrate the MAB concept with a distributed memory MIMD (DM-MIMD) environment. The work presented was driven by two goals, efficient use of the resource and ease of use by programmer and end user. We present a model of MABs and describe the major problems faced, giving solutions to them through two case studies.


Applications And Enabling Technology For Nynet Upstate Corridor, Salim Hariri, Geoffrey C. Fox Jan 1994

Applications And Enabling Technology For Nynet Upstate Corridor, Salim Hariri, Geoffrey C. Fox

Northeast Parallel Architecture Center

Current advances in telecommunication and computing will have significant impact on the proliferation of high performance computing and communication (HPCC) applications. With these emerging technologies, it is feasible to run parallel and distributed applications across a high speed wide area network which was not possible a few years ago; the high latency and low bandwidth were the main bottlenecks for the wide area network-based computing. This has lead to the deployment of several high speed networks across the country (eg. NYNET). In this report, we describe some of the HPCC applications and our experiences and lessons learned from running them …


The Virtual Computing Environment, Philip Rousselle, Paul Tymann, Salim Hariri, Geoffrey C. Fox Jan 1994

The Virtual Computing Environment, Philip Rousselle, Paul Tymann, Salim Hariri, Geoffrey C. Fox

Northeast Parallel Architecture Center

A network of supercomputers and high-performance workstations appears to be the only reasonable way to provide adequate computing resources for the Grand Challenge problems of the next century. Such a collection of computers and supporting software environments is called a virtual computing environment (VCE). This paper describes the motivation and goals of the VCE project, followed by a description of the system. The paper concentrates on the runtime aspects of the VCE, and concludes with a discussion of a small prototype system that has been built using the Isis distributed toolkit.


Data Access Reorganizations In Compiling Out-Of-Core Data Parallel Programs On Distributed Memory Machines, Rajesh Bordawekar, Alok Choudhary, Rajeev Thakur Jan 1994

Data Access Reorganizations In Compiling Out-Of-Core Data Parallel Programs On Distributed Memory Machines, Rajesh Bordawekar, Alok Choudhary, Rajeev Thakur

Electrical Engineering and Computer Science - All Scholarship

This paper describes techniques for translating out-of-core programs written in a data parallel language like HPF to message passing node programs with explicit parallel I/O. We describe the basic compilation model and various steps involved in the compilation. The compilation process is explained with the help of an out-of-core matrix multiplication program. We first discuss how an out-of-core program can be translated by extending the method used for translating in-core programs. We demonstrate that straightforward extension of in-core compiler does not work for out-of-core programs. We then describe how the compiler can optimize the code by (1) estimating the I/O …


Passion: Parallel And Scalable Software For Input-Output, Alok Choudhary, Rajesh Bordawekar, Michael Harry, Rakesh Krishnaiyer Jan 1994

Passion: Parallel And Scalable Software For Input-Output, Alok Choudhary, Rajesh Bordawekar, Michael Harry, Rakesh Krishnaiyer

Electrical Engineering and Computer Science - All Scholarship

We are developing a software system called PASSION: Parallel And Scalable Software for Input-Output which provides software support for high performance parallel I/O. PASSION provides support at the language, compiler, runtime as well as file system level. PASSION provides runtime procedures for parallel access to files (read/write), as well as for out-of-core computations. These routines can either be used together with a compiler to translate out-of-core data parallel programs written in a language like HPF, or used directly by application programmers. A number of optimizations such as Two-Phase Access, Data Sieving, Data Prefetching and Data Reuse have been incorporated in …


Precision Measurement Of The Ds*+-Ds+ Mass Difference, Brown, D.; Et Al., M. Thulasidas Jan 1994

Precision Measurement Of The Ds*+-Ds+ Mass Difference, Brown, D.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

We have measured the vector-pseudoscalar mass splitting M(D*+s)-M(D+s)=144.22±0.47±0.37 MeV significantly more precisely than the previous world average. We minimize the systematic errors by also measuring the vector-pseudoscalar mass difference M(D*0)-M(D0) using the radiative decay D*0→D0γ, obtaining [M(D*+s)-M(D+s)]-[M(D*0)-M(D0)] =2.09±0.47±0.37 MeV. This is then combined with our previous high-precision measurement of M(D*0)-M(D0), which used the decay D*0→D0π0. We also measure the mass difference M(D+s)-M(D+)=99.5±0.6±0.3 MeV, using the φπ+ decay modes of the D+s and D+ mesons.


Skin Cancer Diagnosis Using Hierarchical Neural Networks And Fuzzy Logic, Hsi-Chieh Lee Jan 1994

Skin Cancer Diagnosis Using Hierarchical Neural Networks And Fuzzy Logic, Hsi-Chieh Lee

Masters Theses

"Skin cancer, the most common cancer in the United States that affects about 600,000 Americans every year, accounts for 1 % of all cancer deaths. Among all, Malignant Melanoma is the most virulent form of skin cancer that is responsible for 75% of all deaths from skin cancer. In 1992, approximately 32,000 people are expected to develop melanoma and about 6,700 will die. However, even malignant melanoma can be treated successfully if detected in the early phase. Therefore, our research goal is to diagnose skin cancer, especially malignant melanoma.

In this study, only the digitized images obtained from color tumor …


Sbl- The Structural Biology Language, Marius A. Cornea-Hasegan, Dan C. Marinescu Jan 1994

Sbl- The Structural Biology Language, Marius A. Cornea-Hasegan, Dan C. Marinescu

Department of Computer Science Technical Reports

No abstract provided.


Study Of The Five-Charged-Pion Decay Of The Τ Lepton, D. Gibaut, Manoj Thulasidas Jan 1994

Study Of The Five-Charged-Pion Decay Of The Τ Lepton, D. Gibaut, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

The branching fractions for the five-charged-particle decays of the τ lepton have been measured in e+e− annihilations using the CLEO II detector at the Cornell Electron Storage Ring. Assuming all charged particles to be pions, the results are B(3π−2π+≥0 neutrals ντ)=(0.097±0.005±0.011)%, B(3π−2π+ντ)=(0.077±0.005 ±0.009)%, B(3π−2π+π0ντ)=(0.019±0.004±0.004)%, and B(3π−2π+2π0ντ)B(3π−2π−π0ντ) is measured for the first time by exclusive π0 reconstruction. The results are compared with the predictions from the partially conserved-axial-current and conserved-vector-current hypotheses assuming isospin invariance.


Measurement Of Cabibbo-Suppressed Decays Of The Τ Lepton, Battle, M.; Et Al., M. Thulasidas Jan 1994

Measurement Of Cabibbo-Suppressed Decays Of The Τ Lepton, Battle, M.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

No abstract provided.


Resolving Attribute Incompatibility In Database Integration: An Evidential Reasoning Approach, Ee-Peng Lim, Shashi Shekhar Jan 1994

Resolving Attribute Incompatibility In Database Integration: An Evidential Reasoning Approach, Ee-Peng Lim, Shashi Shekhar

Research Collection School Of Computing and Information Systems

Resolving domain incompatibility among independently developed databases often involves uncertain information. DeMichiel (1989) showed that uncertain information can be generated by the mapping of conflicting attributes to a common domain, based on some domain knowledge. The authors show that uncertain information can also arise when the database integration process requires information not directly represented in the component databases, but can be obtained through some summary of data. They therefore propose an extended relational model based on Dempster-Shafer theory of evidence (1976) to incorporate such uncertain knowledge about the source databases. They also develop a full set of extended relational operations …


A Semantic Framework For Understanding The Behavior Of Modules And Classes In Programming Languages, Mahesh Dodani, Benjamin Kok Siew Gan Jan 1994

A Semantic Framework For Understanding The Behavior Of Modules And Classes In Programming Languages, Mahesh Dodani, Benjamin Kok Siew Gan

Research Collection School Of Computing and Information Systems

Recent trends in programming language design and implementation are aimed at integrating the two most important constructs to combat complexity: modules and classes. Both constructs provide encapsulation, a cornerstone of reliable programming. These constructs differ in their approach to building hierarchies: modules define visibility of components while classes define visibility of functionality. How can modules and classes be effectively integrated within a simple programming language? This question captures the essence of developing semantics of these constructs to ensure that they interact in a meaningful way. This paper develops a formal denotational semantic framework for understanding the interaction between classes and …


Managing Risks In Information Technology Projects, Boon Siong Neo, Kwong Sin Leong Jan 1994

Managing Risks In Information Technology Projects, Boon Siong Neo, Kwong Sin Leong

Research Collection School Of Accountancy

The development and implementation of IT (Information Technology) projects are plagued with problems of cost and time overruns. technical inadequacy, inability to meet user requirements. lack of utilization. and failure to achieve anticipated benefits. These problems occur to some projects and not to others because I) IT projects have different profiles of risk. and 2) IT project risks have been managed more or less effectively. This paper synthesizes the literature into four classes of risks. and applies it to evaluate TradeNet. an EDLbased trading system implemented in Singapore in I989. Through a case study of TradeNet. we derived a typology …


Observation Of A New Charmed Strange Meson, Kubota, Y.; Et Al., M. Thulasidas Jan 1994

Observation Of A New Charmed Strange Meson, Kubota, Y.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

No abstract provided.


Parameter Tuning For The Max Expert System, Christopher J. Merz, M. J. Pazzani Jan 1994

Parameter Tuning For The Max Expert System, Christopher J. Merz, M. J. Pazzani

Computer Science Faculty Research & Creative Works

We investigate methods for tuning numeric parameters in Nynex MAX, a telephone trouble screening expert system. Steepest descent, hillclimbing, and simulated annealing parameter adjustment strategies are applied to the problems of maximizing classification accuracy and minimizing misclassification cost. For both of those optimization problems we evaluate each algorithm''s ability to tune initial parameters for several situations


On The Equivalence Of Mceliece's And Niederreiter's Public-Key Cryptosystems, Y. X. Li, Robert H. Deng, X. M. Wang Jan 1994

On The Equivalence Of Mceliece's And Niederreiter's Public-Key Cryptosystems, Y. X. Li, Robert H. Deng, X. M. Wang

Research Collection School Of Computing and Information Systems

It is shown that McEliece's and Niederreiter's public-key cryptosystems are equivalent when set up for corresponding choices of parameters. A security analysis for the two systems based on this equivalence observation, is presented


Neural Network Diagnosis Of Malignant Melanoma From Color Images, Fikret Erçal, Hsi-Chieh Lee, William V. Stoecker, Randy Hays Moss, Anurag Chawla Jan 1994

Neural Network Diagnosis Of Malignant Melanoma From Color Images, Fikret Erçal, Hsi-Chieh Lee, William V. Stoecker, Randy Hays Moss, Anurag Chawla

Computer Science Faculty Research & Creative Works

Malignant melanoma is the deadliest form of all skin cancers. Approximately 32,000 new cases of malignant melanoma were diagnosed in 1991 in the United States, with approximately 80% of patients expected to survive 5 years. Fortunately, if detected early, even malignant melanoma may be treated successfully, Thus, in recent years, there has been rising interest in the automated detection and diagnosis of skin cancer, particularly malignant melanoma. Here, the authors present a novel neural network approach for the automated separation of melanoma from 3 benign categories of tumors which exhibit melanoma-like characteristics. The approach uses discriminant features, based on tumor …


An Improved Characterization Of 1-Step Recoverable Embeddings: Rings In Hypercubes, Jun-Lin Liu, T.J. Sager, Bruce M. Mcmillin Jan 1994

An Improved Characterization Of 1-Step Recoverable Embeddings: Rings In Hypercubes, Jun-Lin Liu, T.J. Sager, Bruce M. Mcmillin

Computer Science Faculty Research & Creative Works

An embedding is 1-step recoverable if any single fault occurs, the embedding can be reconfigured in one reconfiguration step to maintain the structure of the embedded graph. In this paper we present an efficient scheme to construct this type of 1-step recoverable ring embeddings in the hypercube. Our scheme will guarantee finding a 1-step recoverable embedding of a length-k (even) ring in a d-cube where 6 less than or equal to k less than or equal to (3/4)2/sup d/ and d greater than or equal to 3, provided such an embedding exists. Unlike previously proposed schemes, we solve the general …


Exclusive Hadronic B Decays To Charm And Charmonium Final States, Alam, M.; Et Al., M. Thulasidas Jan 1994

Exclusive Hadronic B Decays To Charm And Charmonium Final States, Alam, M.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

We have fully reconstructed decays of both B¯0 and B− mesons into final states containing either D, D*, D**, ψ, ψ’, or χc1 mesons. This allows us to obtain new results on many physics topics including branching ratios, tests of the factorization hypothesis, color suppression, resonant substructure, and the B−−B¯0 mass difference.


Measurement Of The Branching Fraction For D+K-++, Balest, R.; Et Al., M. Thulasidas Jan 1994

Measurement Of The Branching Fraction For D+K-++, Balest, R.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

Using the CLEO II detector at the Cornell Electron Storage Ring we have measured the ratio of branching fractions, B(D+K-++)/(D0K-+)=2.350.160.16. Our recent measurement of scrB(D0K-+) then gives scrB(D+K-++)=(9.30.60.8)%.