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Isospin Mass Splittings From Precision Measurements Of D*-D Mass Differences, D. Bortoletto, Manoj Thulasidas Jan 1992

Isospin Mass Splittings From Precision Measurements Of D*-D Mass Differences, D. Bortoletto, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

Using the decay modes, D*+→D+π0 and D*0→D0π0, we have measured the D*+−D+ and D*0−D0 mass differences to be 140±0.08±0.06 and 142.12±0.05±0.05 MeV, respectively. Combining these measurements with the Particle Data Group average for the D*+−D0 mass difference, we obtain isospin mass splittings for D*+−Dusp*0 and D+−D0 of 3.32±0.08±0.05 and 4.80±0.10 ±0.06 MeV. We discuss the implications of these measurements for models of isospin mass differences and model-dependent estimates of fD.


Measurement Of The Tau Lepton Electronic Branching Fraction, D. Akerib, M. Thulasidas Jan 1992

Measurement Of The Tau Lepton Electronic Branching Fraction, D. Akerib, M. Thulasidas

Research Collection School Of Computing and Information Systems

The tau lepton electron branching fraction has been measured with the CLEO II detector at the Cornell Electron Storage Ring as Be=0.1749±0.0014±0.0022, with the first error statistical and the second systematic. The measurement involves counting electron-positron annihilation events in which both taus decay to electrons, and normalizing to the number of tau-pair decays expected from the measured luminosity. Detected photons in these events constitute a definitive observation of tau decay radiation.


User Authentication And Related Topics: An Annotated Bibliography, Eugene H. Spafford, Stephen A. Weeber Dec 1991

User Authentication And Related Topics: An Annotated Bibliography, Eugene H. Spafford, Stephen A. Weeber

Department of Computer Science Technical Reports

No abstract provided.


A Note On Many-One And 1-Truth-Table Complete Languages, Steven Homer, Stuart A. Kurtz, James S. Royer Dec 1991

A Note On Many-One And 1-Truth-Table Complete Languages, Steven Homer, Stuart A. Kurtz, James S. Royer

Electrical Engineering and Computer Science - Technical Reports

The polynomial time 1-tt complete sets for EXP and RE are polynomial time many-one complete.


An Efficient Neural Algorithm For The Multiclass Problem, Rangachari Anand, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka Dec 1991

An Efficient Neural Algorithm For The Multiclass Problem, Rangachari Anand, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka

Electrical Engineering and Computer Science - Technical Reports

One connectionist approach to the classification problem, which has gained popularity in recent years, is the use of backpropagation-trained feed-forward neural networks. In practice, however, we find that the rate of convergence of net output error is especially low when training networks for multi-class problems. In this paper, we show that while backpropagation will reduce the Euclidean distance between the actual and desired output vectors, the difference between some of the components of these vectors will actually increase in the first iteration. Furthermore, the magnitudes of subsequent weight changes in each iteration are very small, so that many iterations are …


The Fast Fourier Transform, Per Brinch Hansen Dec 1991

The Fast Fourier Transform, Per Brinch Hansen

Electrical Engineering and Computer Science - Technical Reports

This tutorial discusses the fast Fourier transform, which has numerous applications in signal and image processing. The FFT computes the frequency components of a signal that has been sampled at n points in O( n log n) time. We explain the FFT and illustrate it by examples and Pascal algorithms. We assume that you are familiar with elementary calculus.


Parallel Divide And Conquer, Per Brinch Hansen Dec 1991

Parallel Divide And Conquer, Per Brinch Hansen

Electrical Engineering and Computer Science - Technical Reports

We develop a generic divide and conquer algorithm for a parallel tree machine. From the generic algorithm we derive balanced, parallel versions of quicksort and the fast Fourier transform by substitution of data types, variables and statements. The performance of these algorithms is analyzed and measured on a Computing Surface configured as a tree machine with distributed memory.


Do Hypercubes Sort Faster Than Tree Machines?, Per Brinch Hansen Dec 1991

Do Hypercubes Sort Faster Than Tree Machines?, Per Brinch Hansen

Electrical Engineering and Computer Science - Technical Reports

We develop a balanced, parallel quicksort algorithm for a hypercube and compare it with a similar algorithm for a binary tree machine. The performance of the hypercube algorithm is measured on a Computing Surface.


Efficient Maximum-Likelihood Soft-Decision Decoding Of Linear Block Codes Using Algorithm A, Yunghsiang S. Han, Carlos R.P. Hartmann, Chih-Chieh Chen Dec 1991

Efficient Maximum-Likelihood Soft-Decision Decoding Of Linear Block Codes Using Algorithm A, Yunghsiang S. Han, Carlos R.P. Hartmann, Chih-Chieh Chen

Electrical Engineering and Computer Science - Technical Reports

In this report we present a novel and efficient maximum-likelihood soft-decision decoding algorithm for linear block codes. The approach used here is to convert the decoding problem into a search problem through a graph which is a trellis for an equivalent code of the transmitted code. Algorithm A*, which uses a priority-first search strategy, is employed to search through this graph. This search is guided by an evaluation function f defined to take advantage of the information provided by the received vector and the inherent properties of the transmitted code. This function f is used to drastically reduce the search …


Knowledge-Based Systems Approach For Offshore Safety Training, B. S. Lee, Venky Shankararaman Dec 1991

Knowledge-Based Systems Approach For Offshore Safety Training, B. S. Lee, Venky Shankararaman

Research Collection School Of Computing and Information Systems

A number of training methods has been used within the offshore industry to impart safety knowledge and safe operating skills. In this paper a Knowledge-Based Safety Training architecture is proposed. The architecture uses both expert system and hypertext methods and is also applicable to plants other than offshore platforms. Special attention is given to the types of knowledge dealt with in safety training and how to represent this knowledge and teach it using various teaching strategies.


An Expert System For Measuring, Interpreting, And Managing System Performance Factors For The Work Information Management System, Billy J. C. Irwin Dec 1991

An Expert System For Measuring, Interpreting, And Managing System Performance Factors For The Work Information Management System, Billy J. C. Irwin

Theses and Dissertations

This study develops an expert system for measuring, interpreting, and managing the Wang VS operating system performance factors for the Work Information Management System. The system's performance concerns least known to system administrators are identified. Of these, SHARER buffers and VTOC cache are identified as factors that can significantly impact system performance with little effort. A six step process is used in developing the expert system. Concept maps representing the structure of the Wang VS Disk Input/Output problem domain are provided. The expert system provides information about the system parameters, SHARER buffers and VTOC cache, and recommends main memory allocations. …


Relative Utility Of Selected Software Requirement Metrics, James H. Byers Dec 1991

Relative Utility Of Selected Software Requirement Metrics, James H. Byers

Theses and Dissertations

The objective of this study was to determine the relative utility of selected software requirement metrics in assessing the productivity of the software requirements analysis process and the quality of the products of this process. This objective was met by collecting information about the perceptions that practicing software professionals have of the usefulness of various requirement metrics. The study employed a two part methodology. The first part utilized Basili's goal/question/metric paradigm to identify specific goals of the measurement effort and to identify requirement metrics worthy of further investigation. The second part employed a typical research design to gather perceptions that …


Structured Hypermedia Application Development Model (Shadm): A Structured Model For Technical Documentation Application Design, Peter W. Cassell Dec 1991

Structured Hypermedia Application Development Model (Shadm): A Structured Model For Technical Documentation Application Design, Peter W. Cassell

Theses and Dissertations

This research was conducted to determine how a Royal Australian Air Force technical maintenance publication could be transformed into a task oriented hypermedia application and to develop a model that could be used for future similar transformations. The model was developed following in-depth analysis of the existing USAF F-15E maintenance publication set and validation was conducted using a prototype developed in HyperWriter, a commercial hypermedia product. The prototype model was based around the performance of three maintenance tasks on an aircraft sub-subsystem and incorporated online user access to the necessary support data for task completion. Publication managers, producers, and users …


Reducing Requirements Errors Through The Use Of Computer-Aided Software Engineering (Case) Tools And During Requirements Analysis, Marvin B. Key Jr. Dec 1991

Reducing Requirements Errors Through The Use Of Computer-Aided Software Engineering (Case) Tools And During Requirements Analysis, Marvin B. Key Jr.

Theses and Dissertations

This study investigated whether using CASE tools in the requirements analysis phase of software development reduced the software coding errors attributable to requirement analysis. A survey of the population gathered data as to the current practices and efforts in the use of CASE tools. The data was gathered in two groups: a control group and a sample group. The data was analyzed by group and in various combinations to obtain a greater understanding into population trends and tendencies. The results of the research indicate that the Air Force does not use CASE tools to any great extent. Also, error and …


Representation Requirements For Supporting Knowledge-Based Construction Of Decision-Models In Medicine, Tze-Yun Leong Nov 1991

Representation Requirements For Supporting Knowledge-Based Construction Of Decision-Models In Medicine, Tze-Yun Leong

Research Collection School Of Computing and Information Systems

This paper analyzes the medical knowledge required for formulating decision models in the domain of pulmonary infectious diseases (PIDs) with acquired immunodeficiency syndrome (AIDS). Aiming to support dynamic decision-modeling, the knowledge characterization focuses on the ontology of the clinical decision problem. Relevant inference patterns and knowledge types are identified.


An Lr(L) Testing Algorithm, Thomas J. Ssager Nov 1991

An Lr(L) Testing Algorithm, Thomas J. Ssager

Computer Science Technical Reports

A grammar is LR{1} if it can be parsed deterministically from left to right while looking ahead no more than one symbol. Because of the difficulty in generating full LR{l) parsers, many parser generators such as YACC limit themselves to LALR(1} grammars which are a subset of the LR{l) grammars.

Unlike other algorithms in the literature for testing whether a grammar is LR{l), the algorithm presented here uses only the characteristic finite state machine and other structures necessary for creating an LALR{l) parser. Thus, if a parser generator finds that a grammar is not LALR{l), with little additional work the …


The Minlrl Algorithm For Generating Small Lr(L) Parsers, Thomas J. Sager Nov 1991

The Minlrl Algorithm For Generating Small Lr(L) Parsers, Thomas J. Sager

Computer Science Technical Reports

The MINLRl algorithm for finding minimal deterministic parsers for LR(1) grammars is presented. MINLRl also detects whether a grammar is LR(l) with little more work than building the grammar's LALR(l) parser. MINLRl starts by building the characteristic finite state machine, CFSM, for the input grammar and then checks for LR(l)ness. If the input grammar is LR(l), MINLRl transforms the CFSM into a minimal LR(l) parser by creating extra copies of certain states of the CFSM as necessary. The complexity of the algorithm is O(n3l2v2) where n is the number of states in the parser, …


A Reconstruction Of Context-Dependent Document Processing In Sgml, Allen Brown Jr., T. Wakayama, Howard A. Blair Nov 1991

A Reconstruction Of Context-Dependent Document Processing In Sgml, Allen Brown Jr., T. Wakayama, Howard A. Blair

Electrical Engineering and Computer Science - Technical Reports

SGML achieves a certain degree of context-dependent document processing through attributes and linking. These mechanisms are deficient in several respects. To address these deficiencies we propose augmenting SGML's LINK and ATTLISTconstructs with two new mechanisms, coordination and (rule-based) attribution. The latter can be used to specify the result of context-dependent processing in a uniform fashion while considerably increasing SGML's expressive power. We illustrate this enhanced power by sketching a specification of (the result of) document layout that can be encoded in SGML augmented with coordination and attribution.


Constructively Typed Timed Automata, J. F. Peters Iii Nov 1991

Constructively Typed Timed Automata, J. F. Peters Iii

Electrical Engineering and Computer Science - Technical Reports

A new class of communicating automata called typed Timed lnput/Output Automata (tTAi/os) is introduced. A tTAi/o is a predicate automaton used for specifying and reasoning about real-time systems. The typing discipline suggested for predicate automata is in the tradition of Martin-Löf's constructive type theory. A type A is a proposition, which is defined when a prescription for constructing a proof of A is given. A fragment of Girard's linear logic is used in classifying state types. An illustration of the use of tTAi/os in specifying a light-controller is presented. An abstract program is extracted during a proof of an automaton …


Formal Generation Of Executable Assertions For A Fault-Tolerant Parallel Matrix Relaxation, Hanan Lutfiyya, Bruce M. Mcmillin Oct 1991

Formal Generation Of Executable Assertions For A Fault-Tolerant Parallel Matrix Relaxation, Hanan Lutfiyya, Bruce M. Mcmillin

Computer Science Technical Reports

No abstract provided.


On The Question ‘Do We Need Identity?’, William C. Purdy Oct 1991

On The Question ‘Do We Need Identity?’, William C. Purdy

Electrical Engineering and Computer Science - Technical Reports

Sommers posed the question 'Do We Need Identity?' and answered in the negative. According to Sommers, the need for a special identity relation resulted from an arbitrary distinction between concept and object introduced by Frege and retained in modern predicate logic (MPL). This is reflected in the syntactic distinction between predicate and individual constant. Traditional formal logic (TFL) does not respect this distinction and, as a consequence, has no need for a special identity relation. But Sommers' position has not gained general acceptance. On the contrary, it has received considerable criticism. While it is conceded that TFL can express the …


Distributed Memory Compiler Methods For Irregular Problems -- Data Copy Reuse And Runtime Partitioning, Raja Das, Ravi Ponnusamy, Joel Saltz, Dimitri Mavriplis Oct 1991

Distributed Memory Compiler Methods For Irregular Problems -- Data Copy Reuse And Runtime Partitioning, Raja Das, Ravi Ponnusamy, Joel Saltz, Dimitri Mavriplis

Electrical Engineering and Computer Science - Technical Reports

This paper outlines two methods which we believe will play an important role in any distributed memory compiler able to handle sparse and unstructured problems. We describe how to link runtime partitioners to distributed memory compilers. In our scheme, programmers can implicitly specify how data and loop iterations are to be distributed between processors. This insulates users from having to deal explicitly with potentially complex algorithms that carry out work and data partitioning. We also describe a viable mechanism for tracking and reusing copies of off-processor data. In many programs, several loops access the same off-processor memory locations. As long …


Resolution Without Unification, William C. Purdy Oct 1991

Resolution Without Unification, William C. Purdy

Electrical Engineering and Computer Science - Technical Reports

Resolution as an inference procedure forms the basis of most automated theorem-proving and reasoning systems. The most costly constituent of the resolution procedure in its conventional form is unification. This paper describes PCS, a first-order language in which resolution-based inference can be conducted without unification. PCS resembles the language of elementary logic with the difference that singular predicates supplant individual constants and functions. The result is a uniformity in the treatment of individual constants, functions and predicates. An especially costly part of unification is the occur check. Since unification is unnecessary for resolution in PCS, the occur check is completely …


A Practical Hierarchical Model Of Parallel Computation Ll: Binary Tree And Fft Algorithms, Todd Heywood, Sanjay Ranka Oct 1991

A Practical Hierarchical Model Of Parallel Computation Ll: Binary Tree And Fft Algorithms, Todd Heywood, Sanjay Ranka

Electrical Engineering and Computer Science - Technical Reports

A companion paper has introduced the Hierarchical PRAM (H-PRAM) model of parallel computation, which achieves a good balance between simplicity of usage and reflectivity of realistic parallel computers. In this paper, we demonstrate the usage of the model by designing and analyzing various algorithms for computing the complete binary tree, and the FFT/butterfly graph. By concentrating on two problems, we are able to demonstrate the results of different combinations of organizational strategies and different types of sub-models of the H-PRAM. The philosophy in algorithm design is to maximize the number of processors P that are efficiently usable with respect to …


Composite Stock Cutting Through Simulated Annealing, Pipatpong Poshyanonda, Cihan H. Dagli Sep 1991

Composite Stock Cutting Through Simulated Annealing, Pipatpong Poshyanonda, Cihan H. Dagli

Computer Science Technical Reports

This paper explores the use of Simulated Annealing as an optimization technique for the problem Composite Material Stock Cutting. The shapes are not constrained to be convex polygons or even regular shapes. However, due to the composite nature of the material, the orientation of the shapes on the stock is restricted. For placements of various shapes, we show how to determine a cost function, annealing parameters, and performance.


Ilona: An Advanced Cai Tutorial System For The Fundamentals Of Logic, Otto Mayer, Graham E. Oberem, Fillia Makedon Sep 1991

Ilona: An Advanced Cai Tutorial System For The Fundamentals Of Logic, Otto Mayer, Graham E. Oberem, Fillia Makedon

Computer Science Technical Reports

An advanced tutorial system for teaching the fundamentals of logic has been developed to run on UNIX work stations and commonly available micro-computers. An important part of this tutorial is the intelligent problem solving environment which allows students to practise wiriting logical sentences in mathematical notation. A natural language system for intelligent logic narrative analysis (ILONA) allows students to type in their own logical sentences in plain English and then have the computer check their working when they write these in mathematical form. ILONA is an intelligent tutoring system which allows students a great deal of initiative in problem solving …


Fault-Tolerant Parallel Matrix Multiplication With One Iteration Fault Detection Latency, Chul-Eui Hong, Bruce M. Mcmillin Sep 1991

Fault-Tolerant Parallel Matrix Multiplication With One Iteration Fault Detection Latency, Chul-Eui Hong, Bruce M. Mcmillin

Computer Science Technical Reports

The checksum technique is a low cost method to detect errors in matrix operations performed by processor arrays. The fault detection of this method is done only at problem termination, so this method is not an effective fault tolerance technique for large scale matrix multiplication.

This paper presents a new algorithm, the ID algorithm, which minimizes the fault-detection latency, In the ID algorithm, a fault is detected as soon a5 the fault occurs instead of at problem termination. For 112 processors, the fault-latency time of the ID algorithm is l/11 of that of checksum algorithm with a run-time penalty of …


Fault-Tolerant Parallel Matrix Multiplication With One Iteration Fault Detection Latency, Chul-Eui Hong, Bruce M. Mcmillin Sep 1991

Fault-Tolerant Parallel Matrix Multiplication With One Iteration Fault Detection Latency, Chul-Eui Hong, Bruce M. Mcmillin

Computer Science Technical Reports

The checksum technique is a low cost method to detect errors in matrix operations performed by processor arrays. The fault detection of this method is done only at problem termination, so this method is not an effective fault tolerance technique for large scale matrix multiplication.

This paper presents a new algorithm, the ID algorithm, which minimizes the fault-detection latency, In the ID algorithm, a fault is detected as soon a5 the fault occurs instead of at problem termination. For 112 processors, the fault-latency time of the ID algorithm is l/11 of that of checksum algorithm with a run-time penalty of …


Composite Stock Cutting Through Simulated Annealing, Pipatpong Poshyanonda, Cihan H. Dagli Sep 1991

Composite Stock Cutting Through Simulated Annealing, Pipatpong Poshyanonda, Cihan H. Dagli

Computer Science Technical Reports

This paper explores the use of Simulated Annealing as an optimization technique for the problem Composite Material Stock Cutting. The shapes are not constrained to be convex polygons or even regular shapes. However, due to the composite nature of the material, the orientation of the shapes on the stock is restricted. For placements of various shapes, we show how to determine a cost function, annealing parameters, and performance.


Binary Perfect Weighted Coverings (Pwc) I. The Linear Case, G. D. Cohen, S. N. Litsyn, H. F. Mattson Jr Sep 1991

Binary Perfect Weighted Coverings (Pwc) I. The Linear Case, G. D. Cohen, S. N. Litsyn, H. F. Mattson Jr

Electrical Engineering and Computer Science - Technical Reports

This paper deals with an extension of perfect codes to fractional (or weighted) coverings. We shall derive a Lloyd theorem --- a strong necessary condition of existence---and start a classification of these perfect coverings according to their diameter. We illustrate by pointing to list decoding.