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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.


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.


Reuse And Productivity In Integrated Computer-Aided Software Engineering: An Empirical Study, Rajiv D. Banker, Robert J. Kauffman Sep 1991

Reuse And Productivity In Integrated Computer-Aided Software Engineering: An Empirical Study, Rajiv D. Banker, Robert J. Kauffman

Research Collection School Of Computing and Information Systems

Growing competition in the investment banking industry has given rise to increasing demand for high functionality software applications that can be developed in a short period of time. Yet delivering such applications creates a bottleneck in software development activities. This dilemma can be addressed when firms shift to development methods that emphasize software reusability. This article examines the productivity implications of object and repository-based integrated computer-aided software engineering (ICASE) software development in the context of a major investment bank's information systems strategy. The strategy emphasizes software reusability. Our empirical results, based on data from 20 projects that delivered software for …


Visual Knowledge Query Language As A Front-End To Relational Systems, Keng Siau, Kok Phuang Tan, Hock Chuan Chan Sep 1991

Visual Knowledge Query Language As A Front-End To Relational Systems, Keng Siau, Kok Phuang Tan, Hock Chuan Chan

Research Collection School Of Computing and Information Systems

Relational query languages like SQL and QUEL require the users to understand the complex database structure. This is a burden on end users, especially novice end users who access the database on a casual and infrequent basis. To alleviate the need to know the logical database organization, this paper proposes the use of a semantic data model, known as the Enhanced Entity-Relationship (EER) model, as a front-end to the relational systems. A formal, high-level Visual Knowledge Query Language (VKQL) has also been designed for this interface. This language provides for knowledge abstraction as the user communicates only domain knowledge with …


Visual Knowledge Query Language As A Front-End To Relational Systems, Keng Siau, Kok Phuang Tan, Hock Chuan Chan Sep 1991

Visual Knowledge Query Language As A Front-End To Relational Systems, Keng Siau, Kok Phuang Tan, Hock Chuan Chan

Research Collection School Of Computing and Information Systems

Relational query languages like SQL and QUEL require the users to understand the complex database structure. This is a burden on end users, especially novice end users who access the database on a casual and infrequent basis. To alleviate the need to know the logical database organization, this paper proposes the use of a semantic data model, known as the Enhanced Entity-Relationship (EER) model, as a front-end to the relational systems. A formal, high-level Visual Knowledge Query Language (VKQL) has also been designed for this interface. This language provides for knowledge abstraction as the user communicates only domain knowledge with …


Connectionist Expert System With Adaptive Learning Capability, B. T. Low, Hochung Lui, Ah-Hwee Tan, Hoonheng Teh Jun 1991

Connectionist Expert System With Adaptive Learning Capability, B. T. Low, Hochung Lui, Ah-Hwee Tan, Hoonheng Teh

Research Collection School Of Computing and Information Systems

A neural network expert system called adaptive connectionist expert system (ACES) which will learn adaptively from past experience is described. ACES is based on the neural logic network, which is capable of doing both pattern processing and logical inferencing. The authors discuss two strategies, pattern matching ACES and rule inferencing ACES. The pattern matching ACES makes use of past examples to construct its neural logic network and fine-tunes itself adaptively during its use by further examples supplied. The rule inferencing ACES conceptualizes new rules based on the frequencies of use on the rule-based neural logic network. A new rule could …


An Efficient Semantic Query Optimization Algorithm, Hwee Hwa Pang, Hongjun Lu, Beng Chin Lu Apr 1991

An Efficient Semantic Query Optimization Algorithm, Hwee Hwa Pang, Hongjun Lu, Beng Chin Lu

Research Collection School Of Computing and Information Systems

An efficient semantic query optimization algorithm is proposed, in which all possible transformations are tentatively applied to the query. Instead of physically modifying the query, the transformation process classifies the predicates into imperative, optional or redundant. At the end of the transformation process, all the imperative predicates are retained while the redundant predicates are eliminated. Optional predicates are retrained or discarded based on the estimated cost/benefit of retaining them. The issue of the grouping of semantic constraints to reduce the overhead of retrieving constraints and checking whether each constraint is relevant to the current query is also addressed. Based on …


Fuzzy Neural Logic Network And Its Learning Algorithms, Fiona Fui-Hoon Nah, Nah Fiona Jan 1991

Fuzzy Neural Logic Network And Its Learning Algorithms, Fiona Fui-Hoon Nah, Nah Fiona

Research Collection School Of Computing and Information Systems

The paper introduces the basic features of fuzzy neural logic network. Each fuzzy neural logic network model is trained from a set of knowledge in the form of examples using one of the three learning algorithms introduced. These three learning algorithms are the delta rule controlled learning algorithm and two mathematical construction algorithms, namely, the local learning method and the global learning method. Once the fuzzy neural logic network model is constructed, it is ready to accept any unknown input from the user. With a low percentage of mismatched features, output solution can be obtained.


Inclusive Production Of The Charmed Baryon C+ From E+E- Annihilations At S=10.55 Gev, P. Avery, Manoj Thulasidas Jan 1991

Inclusive Production Of The Charmed Baryon C+ From E+E- Annihilations At S=10.55 Gev, P. Avery, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

We report results on inclusive production of the charmed baryon Λc+ from e+e− annihilations at √s=10.5 GeV. Measurements are presented of the inclusive cross section times branching fraction for the continuum production of Λc+ as observed in six different decay modes, and of a new, improved value of the Λc+ mass. The inclusive cross section times the branching fraction into pK−π+ is measured to be 10.0±1.5±1.5 pb summed over all xp. The branching fractions of Λc+ into p¯K0, p¯K0π+π−, Λπ+, Λπ+π−π+, and Ξ−K+π+ relative to that into pK−π+ are measured to be 0.44±0.07±0.05, 0.43±0.12±0.04, 0.18±0.03±0.03, 0.65±0.11±0.12, and 0.15±0.04±0.03, respectively. The …


Exclusive And Inclusive Semileptonic Decays Of B Mesons To D Mesons, R. Fulton, M. Thulasidas Jan 1991

Exclusive And Inclusive Semileptonic Decays Of B Mesons To D Mesons, R. Fulton, M. Thulasidas

Research Collection School Of Computing and Information Systems

We report new measurements of the branching fractions B ( B − → D 0 l − ¯ ν ) , B ( ¯ B 0 → D + l − ¯ ν ) , and B ( B − → D * 0 l − ¯ ν ) . Combining these results with our previous measurement of B ( ¯ B 0 → D * + l − ¯ ν ) , we find that the ratio of semileptonic widths for final states with a vector meson and pseudoscalar meson is ( 2.6 + 1.1 + 1.0 − 0.6 …


A Graphical Knowledge Level Approach For User-Database Interaction, K. Tan, H. Chan, Keng Siau Nov 1990

A Graphical Knowledge Level Approach For User-Database Interaction, K. Tan, H. Chan, Keng Siau

Research Collection School Of Computing and Information Systems

The authors propose a novel user interface, the Graphical Knowledge Level interface, for user-database interaction. This interface addresses two of the current research problems: the semantic inadequacy of the relational model and the logical data dependence of the relational languages. The interface is more user-friendly than the SOL interface and the Universal Relation interface, as it employs the graphical approach. The semantic inadequacy problem is alleviated by using an enhanced entity-relationship model. This data model includes abstraction concepts such as aggregation, generalization, and categorization. A formal, high-level Graphical Knowledge Level Query Language, GKQL, which provides for both logical and physical …


Gateway Design For Lan Interconnection Via Isdn, Xian-Yu Zhang, Robert H. Deng Sep 1990

Gateway Design For Lan Interconnection Via Isdn, Xian-Yu Zhang, Robert H. Deng

Research Collection School Of Computing and Information Systems

Recently, the use of bridges/gateways to interconnect physically distant local area networks (LANs) has become increasingly popular. There are various ways of connecting these bridges/gateways. ISDN is one of them and an attractive one. In this paper we discuss our work in the gateway design for interconnecting LANs via ISDN.


Measurement Of The C+ Decay-Asymmetry Parameter, Avery, P.; Et Al., M. Thulasidas Jan 1990

Measurement Of The C+ Decay-Asymmetry Parameter, Avery, P.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

We report a measurement of polarization in the two-body decay c+, in nonresonant e+e- interactions from data taken with the CLEO detector. Using these data we have determined the parity-violating asymmetry decay parameter c to be -1.0-0.0+0.4. We see no evidence for significant c+ polarization.


Observation Of B-Meson Semileptonic Decays To Noncharmed Final States, Fulton, R.; Et Al., M. Thulasidas Jan 1990

Observation Of B-Meson Semileptonic Decays To Noncharmed Final States, Fulton, R.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

No abstract provided.


Observation Of Iv(4=S) Decays Into Non-=Bba Final States Containing I Mesons, Alexander, J.; Et Al., M. Thulasidas Jan 1990

Observation Of Iv(4=S) Decays Into Non-=Bba Final States Containing I Mesons, Alexander, J.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

We report on the observation of ; mesons from T(4S) decays which are too energetic to come from 8 mesons. These events provide evidence for non-88 decays of the T (4S). The measured rate is B(T(4S)+fX)=0.22•0.06•0.041 for ; momentum above 2 GeV/c.


Exclusive And Inclusive Decays Of B Mesons Into Ds Mesons, D. Bortoletto, Manoj Thulasidas Jan 1990

Exclusive And Inclusive Decays Of B Mesons Into Ds Mesons, D. Bortoletto, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

We have studied the production of Ds mesons in the decays of B mesons at the Υ(4S) resonance. We report on the first observation of exclusive B-meson decays B->Ds−D*+, B→Ds−D+, and B→Ds−D0. We also present a new measurement of the branching ratio and the momentum spectrum for the inclusive decay B→DsX.


Trellis-Coded Multidimensional Phase Modulation, S. S. Pietrobon, Robert H. Deng Jan 1990

Trellis-Coded Multidimensional Phase Modulation, S. S. Pietrobon, Robert H. Deng

Research Collection School Of Computing and Information Systems

A 2L-dimensional multiple phase-shift keyed (L×MPSK) signal set is obtained by forming the Cartesian product of L two-dimensional MPSK signal sets. A systematic approach to partitioning L×MPSK signal sets that is based on block coding is used. An encoder system approach is developed. It incorporates the design of a differential precoder, a systematic convolutional encoder, and a signal set mapper. Trellis-coded L×4PSK, L×8PSK, and L×16PSK modulation schemes are found for 1⩽L⩽4 and a variety of code rates and decoder complexities, many of which are fully transparent to discrete phase rotations of the signal set. The new codes achieve asymptotic coding …


Parity Retransmission Hybrid Arq Using Rate 1/2 Convolutional Codes On A Nonstationary Channel, L. R. Lugand, D. J. Costello, Jr., Robert H. Deng Jul 1989

Parity Retransmission Hybrid Arq Using Rate 1/2 Convolutional Codes On A Nonstationary Channel, L. R. Lugand, D. J. Costello, Jr., Robert H. Deng

Research Collection School Of Computing and Information Systems

A parity retransmission hybrid automatic repeat request (ARQ) scheme is proposed which uses rate 1/2 convolutional codes and Viterbi decoding. A protocol is described which is capable of achieving higher throughputs than previously proposed parity retransmission schemes. The performance analysis is based on a two-state Markov model of a nonstationary channel. This model constitutes a first approximation to a nonstationary channel. The two-state channel model is used to analyze the throughput and undetected error probability of the protocol presented when the receiver has both an infinite and a finite buffer size. It is shown that the throughput improves as the …


High Rate Concatenated Coding Systems Using Bandwidth Efficient Trellis Inner Codes, Robert H. Deng, D. J. Costello, Jr. May 1989

High Rate Concatenated Coding Systems Using Bandwidth Efficient Trellis Inner Codes, Robert H. Deng, D. J. Costello, Jr.

Research Collection School Of Computing and Information Systems

High-rate concatenated coding systems with bandwidth-efficient trellis inner codes and Reed-Solomon (RS) outer codes are investigated for application in high-speed satellite communication systems. Two concatenated coding schemes are proposed. In one the inner code is decoded with soft-decision Viterbi decoding, and the outer RS code performs error-correction-only decoding (decoding without side information). In the other the inner code is decoded with a modified Viterbi algorithm, which produces reliability information along with the decoded output. In this algorithm, path metrics are used to estimate the entire information sequence, whereas branch metrics are used to provide reliability information on the decoded sequence. …


Impacts Of Industrial Robotics: Potential Effects On Labor And Costs Within The Metalworking Industries, Steven M. Miller Mar 1989

Impacts Of Industrial Robotics: Potential Effects On Labor And Costs Within The Metalworking Industries, Steven M. Miller

Research Collection School Of Computing and Information Systems

According to leading expert opinion, industrial robots are among the most important innovations of recent decades. Yet there is very considerable uncertainty (and disagreement) as to the rate at which the use of robots will spread and what their effects on employment, costs, and market structure will be. As stressed in 1983 by Congress’s Office of Technology Assessment: “A central question for an analysis of the social and economic impacts of programmable automation is whether programmable automation is likely to spread especially rapidly among firms and industries, and why.” The author analyzes the job displacement effects of industrial robots, as …


Dc-Free Coset Codes, Robert H. Deng, M. A. Herro Jul 1988

Dc-Free Coset Codes, Robert H. Deng, M. A. Herro

Research Collection School Of Computing and Information Systems

An upper bound on the bit-error probability (BEP) of a linear cyclic code over GF(2l) with hard-decision (HD) maximum-likelihood (ML) decoding on memoryless symmetric channels is derived. Performance results are presented for Reed-Solomon codes on GF(32), GF(64), and GF(128). Also, a union upper bound on the BEP of a linear cyclic code with either hard- or soft-decision ML decoding is developed, as well as the corresponding bounds for the extended code of a linear cyclic code. Using these bounds, which are tight at low bit error rate, the performance advantage of soft-decision (SD) ML and HD ML over bounded-distance (BD) …


Decoding Of Dbec-Tbed Reed-Solomon Codes, Robert H. Deng, Daniel J. Jr. Costello Nov 1987

Decoding Of Dbec-Tbed Reed-Solomon Codes, Robert H. Deng, Daniel J. Jr. Costello

Research Collection School Of Computing and Information Systems

A problem in designing semiconductor memories is to provide some measure of error control without requiring excessive coding overhead or decoding time. In LSI and VLSI technology, memories are often organized on a multiple bit (or byte) per chip basis. For example, some 256K bit DRAM's are organized in 32K ?? 8 bit-bytes. Byte-oriented codes such as Reed-Solomon (RS) codes can provide efficient low overhead error control for such memories. However, the standard iterative algorithm for decoding RS codes is too slow for these applications. In this correspondence we present a special decoding technique for double-byte-error-correcting (DBEC), triple-byte-error-detecting (TBED) RS …


Impact Of Automation On Process Control Decision-Making, Steven M. Miller, Susan R. Bereiter Jan 1987

Impact Of Automation On Process Control Decision-Making, Steven M. Miller, Susan R. Bereiter

Research Collection School Of Computing and Information Systems

This paper investigates changes in the process control of a vehicle assembly plant which had been modernized from a principally manual procedure to one that uses programmable automation extensively. Process control is defined as the information flow and decision-making required to perform basic process operations. We investigate the effects of implementing a computer-integrated production system on the amount and types of process control decision-making and on the distribution of process control decision-making between humans and machines. After automation, the emphasis on decisions regarding product quality specifications increased and the emphasis on decisions related to flexibility in handling a variety of …


Impacts Of Robotics And Flexible Manufacturing Technologies On Manufacturing Costs And Employment, Steven M. Miller Jan 1985

Impacts Of Robotics And Flexible Manufacturing Technologies On Manufacturing Costs And Employment, Steven M. Miller

Research Collection School Of Computing and Information Systems

The issues analyzed in this paper are the extent to which unit costs and production labor requirements might be reduced in manufacturing industries if there is more widespread use of industrial robots and flexible systems. The analysis is reported in detail in Miller (1983). These issues are analyzed from two different perspectives. The technological focus of the first perspective is narrowly confined to the use of robotic manipulators. It is assumed that robotic manipulators will be “retrofitted” into existing production facilities without making major changes in the organization of production within the factory, other than modifying individual work stations so …


Robotic Realities: Near Term Prospects And Problems, Robert U. Ayres, Steven M. Miller Nov 1983

Robotic Realities: Near Term Prospects And Problems, Robert U. Ayres, Steven M. Miller

Research Collection School Of Computing and Information Systems

Industrial robots are automation, but with a difference. Other machine tools are extensions of human capabilities, while robots are seen mainly as substitutes for human workers. Robots will find most of their industrial applications during the next decade or two in the metal-working sectors, where they will begin to displace semiskilled machine operatives in medium to large batch production operations. They cannot substitute for skilled machinists or other workers doing nonroutine jobs, or specialized, dedicated hard automation used in mass production. The current generation of robots, lacking sensory data processing and interpretation capabilities, can potentially replace up to 1.3 million …


Robotics And The Conservation Of Human Resources, Robert U. Ayres, Steven M. Miller Jan 1982

Robotics And The Conservation Of Human Resources, Robert U. Ayres, Steven M. Miller

Research Collection School Of Computing and Information Systems

Due to rapid expansion in the field of robotics, policy issues have arisen in regard to developing human skills to deal with the new technology and to deal with the obsolescent human skills which are the inevitable result of this growth pattern. Industrialists, educators, union leaders, and government officials must work cooperatively to insure that the coming changes are made with minimum disruption. Improved training methods and courses have to be developed for the skills needed to control, manage and supervise the new machines. Some of the ways in which this can be accomplished are through offering financial incentives for …


The Role Of Technological Change, Robert U. Ayres, Steven M. Miller Dec 1980

The Role Of Technological Change, Robert U. Ayres, Steven M. Miller

Research Collection School Of Computing and Information Systems

We develop an optimal growth model that includes several important new features. First, technological change is endogenously related to the growth of 'knowledge.' Investment may be directed either towards physical capital or knowledge (or both). Knowledge becomes an effective substitute for scarce resources by increasing the technical efficiency of resource utilization both for consumption and in capital. Nevertheless, a finite quantity resource must be embodied in capital and a finite flow is required for depreciation. Thus, there is an upper limit to technical efficiency and economic growth is thus ultimately limited by the availability of renewable resources. For a simple …


Correction To "Redundancy Optimization Of General Systems", H. Sivaramakrishnan, Arcot Desai Narasimhalu Dec 1979

Correction To "Redundancy Optimization Of General Systems", H. Sivaramakrishnan, Arcot Desai Narasimhalu

Research Collection School Of Computing and Information Systems

Reader Aids-

Purpose: Report a correction

Special math needed: Probability

Results useful to: Reliability Theoreticians


Efficient Employment Of Cohorts Of Labor In The U.S. Economy: An Illustration Of A Method, A. E. Boardman, Steven M. Miller, A. P. Schinnar Jul 1979

Efficient Employment Of Cohorts Of Labor In The U.S. Economy: An Illustration Of A Method, A. E. Boardman, Steven M. Miller, A. P. Schinnar

Research Collection School Of Computing and Information Systems

This paper presents a model for the analysis of efficient labor force participation in the U.S. economy. Ridge regression estimates of the elasticities of cohorts of labor, classified by sex and occupation, are used in conjunction with wage data to illustrate the derivation of efficient allocation of labor cohorts in five economic sectors. These efficient constructs are compared with actual census data for 1960 and 1970. The results, while tentative, show a trend toward more efficient utilization of labor and greater participation by women in the work force.


A Rapid Algorithm For Reliability Optimization Of Parallel Redundant Systems, Arcot Desai Narasimhalu, H. Sivaramakrishnan Oct 1978

A Rapid Algorithm For Reliability Optimization Of Parallel Redundant Systems, Arcot Desai Narasimhalu, H. Sivaramakrishnan

Research Collection School Of Computing and Information Systems

A rapid method is proposed for optimization of reliability of multiconstraint parallel redundant systems. The constraints need not be linear. This method provides good starting values, which are close to the boundary of the feasible region, for the number of redundant units in each subsystem. No proof has been presented to establish the optimality obtained by this method. Yet for examples tried out this method provides optimal or near optimal solutions.