Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Computer Sciences

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 61111 - 61140 of 63816

Full-Text Articles in Entire DC Network

Distributed Scheduling Of Unstructured Collective Communication On The Cm-5 (1993), Jyu-Chun Wang, Tseng-Hui Lin, Sanjay Ranka Jan 1993

Distributed Scheduling Of Unstructured Collective Communication On The Cm-5 (1993), Jyu-Chun Wang, Tseng-Hui Lin, Sanjay Ranka

College of Engineering and Computer Science - Former Departments, Centers, Institutes and Projects

Parallelization of many irregular applications results in unstructured collective communication. In this paper we present a distributed algorithm for scheduling such communication on parallel machines. We describe the performance of this algorithm on the CM-5 and show that the scheduling algorithm has very small overhead and gives a significant improvement over naive methods.

Go to article

Ccis Networking - January 1993, Nova University Jan 1993

Ccis Networking - January 1993, Nova University

CCIS Networking / SCIS Networking magazines

No abstract provided.

Go to article

Georg Cantor And The Battle For Transfinite Set Theory, Joseph Dauben Jan 1993

Georg Cantor And The Battle For Transfinite Set Theory, Joseph Dauben

ACMS Journal 2004

Georg Cantor is well known as the founder of transfinite set theory. Equally celebrated, however, are the obstacles he faced in trying to win acceptance for his seemingly unorthodox views, his acrimonious differences with Leopold Kronecker and his unfortunate but progressively debilitating nervous breakdowns that some authors have linked directly to his many problems with set theory. Above all, Cantor's justification of set theory was all the more urgent because of Kronecker's critical denunciation of Cantor's mathematics. In tracing the evolution of Cantorian set theory, it is necessary to examine the opposition it met, and evaluate the technical, philosophical, psychological, …

Go to article

Monitoring Shared Memory: A Toolset Prototype For The Informix Online Administrator, Eric Gronholz Jan 1993

Monitoring Shared Memory: A Toolset Prototype For The Informix Online Administrator, Eric Gronholz

Honors Theses, 1963-2015

The "Monitor" Program was developed to assist system administrators for the INFORMIX OnLine Database Server with their evaluation of shared memory components used on their system. Using the Open Software Foundation (OSF)/Motif Widget set for Xt Intrinsics on the X Window System, this program creates scaled dials and pop-up windows to display system information at regular intervals. The program is surprisingly simple to operate and is general enough that with just a few modifications, it can be used to monitor any system information, not just shared memory information for OnLine. This program marks a new way to look at systems …

Go to article

Software And Hardware Support For Workstation-Based, Salim Hariri, Manish Parashar, Jongbaek Park Jan 1993

Software And Hardware Support For Workstation-Based, Salim Hariri, Manish Parashar, Jongbaek Park

Electrical Engineering and Computer Science - All Scholarship

The proliferation of high performance workstations and the emergence of high speed networks have attracted a lot of interest in workstation-based supercomputing. We project that workstation-based environments with supercomputing capabilities will be available in the not-so-distant future. However a number of hardware and software issues have to be resolved before the full potential of these workstation-based supercomputing environments can be exploited. The presented research has two main objectives: (1) to investigate the limitations of communications techniques used in current workstation-based systems and to identify a set of requirements that must be satisfied to achieve workstation-based supercomputing; (2) to use these …

Go to article

On Extremal Nonsupereulerian Graphs With Clique Number M, Zhi-Hong Chen Jan 1993

On Extremal Nonsupereulerian Graphs With Clique Number M, Zhi-Hong Chen

Scholarship and Professional Work - LAS

No abstract provided.

Go to article

On The Edge Arboricity Of A Random Graph, P. A. Catlin, Zhi-Hong Chen, E. M. Palmer Jan 1993

On The Edge Arboricity Of A Random Graph, P. A. Catlin, Zhi-Hong Chen, E. M. Palmer

Scholarship and Professional Work - LAS

No abstract provided.

Go to article

Integrated Computer Controlled Sensor Monitor, Tariq Hafeez Malik Jan 1993

Integrated Computer Controlled Sensor Monitor, Tariq Hafeez Malik

Theses : Honours

This research has developed an Integrated Computer Controlled Sensor Monitor (ICCSM) environment, to monitor and analyse alarm events associated with sensors, including an interface between a PC and a number of detectors. Such an environment will help the security industry analyse the factors causing false alarms at particular locations. The ICCSM environment monitors, and records, alarm data. Knowing exactly which sensor has been activated, and its location, is of paramount importance to the effective deployment of response forces and making the identification of causes of spurious alarms easier. The lCCSM environment is a combination of software and general purpose hardware, …

Go to article

So Far (Schematically) Yet So Near (Semantically), Amit P. Sheth, Vipul Kashyap Jan 1993

So Far (Schematically) Yet So Near (Semantically), Amit P. Sheth, Vipul Kashyap

Kno.e.sis Publications

In a multidatabase system, schematic conflicts between two objects are usually of interest only when the objects have some semantic affinity. In this paper we try to reconcile the two perspectives. We first define the concept of semantic proximity and provide a semantic taxonomy. We then enumerate and classify the schematic and data conflicts. We discuss possible semantic similarities between two objects that have various types of schematic and data conflicts. Issues of uncertain information and inconsistent information are also addressed.

Go to article

The Washington University Multimedia System, William D. Richard, Jerome R. Cox Jr., Brian Gottlieb, Ken Krieger Jan 1993

The Washington University Multimedia System, William D. Richard, Jerome R. Cox Jr., Brian Gottlieb, Ken Krieger

All Computer Science and Engineering Research

The Washington University Multimedia System (MMS) is a complete multimedia system capable of transmitting and receiving video, audio, and radiological images, in addition to normal network traffic, over the Washingon University broadband ATM network. The MMS consists of an ATMizer and three multimedia subsystems. The ATMizer implements the host interface, the interface to the ATM network, and the interface to the three multimedia subsystems. The video sybsystem encodes and decodes JPEG compressed video using two hardware compression engines. The audio subsystem encodes and decodes CD-quality stereo audio. The high-speed radiological image subsystem reformats radiological image data transmitted by a dedicated …

Go to article

A Fault Tolerant Connectionist Architecture For Construction Of Logic Proofs, Gadi Pinkas Jan 1993

A Fault Tolerant Connectionist Architecture For Construction Of Logic Proofs, Gadi Pinkas

All Computer Science and Engineering Research

This chapter considers the problems of expressing logic and constructing proofs in fault tolerant connectionist networks that are based on energy minimalism. Given a first-order-logic knowledge base and a bound k, a symmetric network is constructed (like a Boltzman machine or a Hopfield network) that searches for a proof for a given query. If a resolution-based proof of length no longer than k exists, then the global minima of the energy function that is associated with the network represent such proofs. If no proof exist then the global minima indicate the lack of a proof. The network that is generated …

Go to article

Research Proposal: Preference Acquisition Through Reconciliation Of Inconsistencies, Nilesh L. Jain Jan 1993

Research Proposal: Preference Acquisition Through Reconciliation Of Inconsistencies, Nilesh L. Jain

All Computer Science and Engineering Research

The quality of performance of a decision-support system (or an expert system) is determined to a large extent by its underlying preference model (or knowledge base). The difficulties in preference and knowledge acquisition make them a major focus of current research in decision-support and expert systems. Researchers have used various concepts to develop promising acquisition techniques. One of the concepts used is knowledge maintenence where the knowledge base is changed in response to incorrect or inadequate performance by the expert system. This dissertation investigates a preference acquisition technique based on the reconciliation of inconsistencies between the preference model and the …

Go to article

Clinical Decision-Support Systems In Radiation Therapy, Nilesh L. Jain, Michael G. Kahn Jan 1993

Clinical Decision-Support Systems In Radiation Therapy, Nilesh L. Jain, Michael G. Kahn

All Computer Science and Engineering Research

Computers have been used in radiation therapy since the early 1960s to perform dose calculations. In the last decade, researchers have developed computer-based clinical decision-support systems for assisting in different decision-making tasks in radiation therapy. This paper reviews eleven prototype systems developed for target volume delineation, treatment planning, treatment plan evaluation, and treatment machine diagnosis. The advent of three-dimensional (3D) conformal radiation therapy (CRT) provides radiation oncologists with the opportunity to consider innovative beam arrangements which were not possible in two-dimensional class solutions. The difficulty of manually generating the thousands of clinically plausible 3D treatment plans calls for the use …

Go to article

A Characterization Of The Computational Power Of Rule-Based Visualization, Kenneth C. Cox, Gruia-Catalin Roman Jan 1993

A Characterization Of The Computational Power Of Rule-Based Visualization, Kenneth C. Cox, Gruia-Catalin Roman

All Computer Science and Engineering Research

Declarative visualization is a paradigm in which the process of visualization is treated as a mapping from some domain (typically a program) to an image. One means of declaring such mappings is through the use of rules which specify the relationship between the domain and the image. This paper examines the computational power of such rule-based mappings. Computational power is measure using three separate criteria. The first of these uses the Chomsky hierarchy, in which computational power is treated as string-acceptance; with this criterion we are able to show that certain rule-based models are equivalent in power to Turing machines. …

Go to article

Supervised Competitive Learning With Backpropagation Network And Fuzzy Logic, Takayuki Dan Kimura, Thomas H. Fuller Jr., Ce Wang Jan 1993

Supervised Competitive Learning With Backpropagation Network And Fuzzy Logic, Takayuki Dan Kimura, Thomas H. Fuller Jr., Ce Wang

All Computer Science and Engineering Research

SCL assembles a set of learning modules into a supervised learning system to address the stability-plasticity dilemma. Each learning module acts as a similarity detector for a prototype, and includes prototype resetting (akin to that of ART) to respond to new prototypes. Here (Part I) we report SCL results using back-propagation networks as the learning modules. We used two feature extractors: about 30 energy-based features, and a combination of energy-based and graphical features (about 60). ACL recognized 96% (energy) and 99% (energy/graphical) of test digits, and 91% (energy) and 96% (energy/graphical) of test letters. In the accompanying paper (Part II), …

Go to article

Approximation Algorithms For Configuring Hierarchical Nonblocking Communication Networks, J. Andrew Fingerhut Jan 1993

Approximation Algorithms For Configuring Hierarchical Nonblocking Communication Networks, J. Andrew Fingerhut

All Computer Science and Engineering Research

A framework is given for specifying nonblocking traffic limits in a connection-oriented communications network. In this framework, connections may be point-to-point or mutlipoint, and the data rates may vary from one connection to another. The traffic limits may be "flat", or they may also be hierarchical, representing communities of interest within the network that have higher traffic among themselves than with the rest of the network. The communication networks are constructed from switches (or nodes) and trunks, which connect pairs of switches. This framework is intended to model Asynchronous Transfer Mode (ATM) networks and traffic. We present a way of …

Go to article

Teaching A Smarter Learner, Sally A. Goldman, H. David Mathias Jan 1993

Teaching A Smarter Learner, Sally A. Goldman, H. David Mathias

All Computer Science and Engineering Research

We introduce a formal model of teaching in which the teacher is tailored to a particular learner, yet the teaching protocol is designed so that no collusion is possible. Not surprisingly, such a model remedies the non-intuitive aspects of otehr models in which the teacher must successfully teach any consistent learner. We prove that any class that can be exactly identified by a deterministic polynomial-time algorithm with access to a very rich set of example-based queries is teachable by a computationally unbounded teacher and a polynomial-time learner. In addition, we present other general results relating this model of teaching to …

Go to article

Improving The Speed Of A Distributed Checkpointing Algorithm, Sachin Garg, Kenneth F. Wong Jan 1993

Improving The Speed Of A Distributed Checkpointing Algorithm, Sachin Garg, Kenneth F. Wong

All Computer Science and Engineering Research

This paper shows how Koo and Toueg's distributed checkpointing algorithm can be modified so as to substantially reduce the average message volume. It attempts to avoid O(n{squared}) messages by using dependency knowledge to reduce the number of checkpoint request messages. Lemmas on consistency and termination are also included.

Go to article

Dynamic Reconfiguration With I/O Abstraction, Bala Swaminathan, Kenneth J. Goldman Jan 1993

Dynamic Reconfiguration With I/O Abstraction, Bala Swaminathan, Kenneth J. Goldman

All Computer Science and Engineering Research

Dynamic reconfiguration is explored in the context of I/O abstraction, a new programming model that defines the communication structure of a system in terms of connections among well-defined data interfaces for the modules in the system. The properties of I/O abstraction, particularly the clear separation of computation from communication and the availability of a module's state information, help simplify the reconfiguration strategy. Both logical and physical reconfiguration are discussed, with an emphasis on a new module migration mechanism that (1) takes advantage of the underlying I/O abstraction model, (2) avoids the expense and complication of state extraction techniques, (3) minimizes …

Go to article

A Taxonomy Of Program Visualization Systems, Gruia-Catalin Roman, Kenneth C. Cox Jan 1993

A Taxonomy Of Program Visualization Systems, Gruia-Catalin Roman, Kenneth C. Cox

All Computer Science and Engineering Research

Program visualization may be viewed as a mapping from programs to graphical representations. This simple idea provides a formal framework for a new taxonomy of program visualization systems. The taxonomy is compared briefly against previous attempts to organize the program visualization field. The taxonomic principles and their motivation are explained in detail with reference to a number of existing systems, especially Balsa, Tango, and Pavane.

Go to article

Efficiently Computing {Phi}-Nodes On-The-Fly, Ron K. Cytron, Jeanne Ferrante Jan 1993

Efficiently Computing {Phi}-Nodes On-The-Fly, Ron K. Cytron, Jeanne Ferrante

All Computer Science and Engineering Research

Recently, Static Single Assignment Form and Sparse Evaluation Graphs have been advanced for the efficient solution of program optimization problems. Each method is provided with an initial set of flow graph nodes that inherently affect a problem's solution. Other relevant nodes are those where potentially disparate solutions must combine. Previously, these so-called {phi}-nodes were found by computing the iterated dominance frontiers of the initial set of nodes, a process that could take worst case quadratic time with respect to the input flow graph. In this paper we present an almost-linear algorithm for detemining exactly the same set of {phi}-nodes.

Go to article

Trainrec: A System For Training Feedforward & Simple Recurrent Networks Efficiently And Correctly, Barry L. Kalman, Stan C. Kwasny Jan 1993

Trainrec: A System For Training Feedforward & Simple Recurrent Networks Efficiently And Correctly, Barry L. Kalman, Stan C. Kwasny

All Computer Science and Engineering Research

TRAINREC is a system for training feedforward and recurrent neural networks that incorporates several ideas. It uses the conjugate-gradient method which is demonstrably more efficient than traditional backward error propagation. We assume epoch-based training and derive a new error function having several desirable properties absent from the traditional sum-of-squared-error function. We argue for skip (shortcut) connections where appropriate and the preference for a sigmoidal yielding values over the [-1,1] interval. The input feature space is often over-analyzed, but by using singular value decomposition, input patterns can be conditioned for better learning often with a reduced number of input units. Recurrent …

Go to article

Logical Interference In Symmetric Connectionist Networks, Gadi Pinkas Jan 1993

Logical Interference In Symmetric Connectionist Networks, Gadi Pinkas

All Computer Science and Engineering Research

This work delineates the relation between logic and symmetric neural networks. The motivation is two-fold: 1) to study the capabilities and limitations of connectionist networks with respect to knowledge representatoin; and 2) to develop a new kind of inference negine that is expressive, massively parallel, capable of coping with nonmonotonic or noisy knowledge and capable of learning. The thesis shows that propositional logic can be implemented efficiently in networks where hidden units allow the representation of arbitrary constraints. An inference engine is constructed which can obtain its knowledge either by compiling symbolic rules or by learning them inductively from examples. …

Go to article

Objective Evaluation Of Radiation Treatment Plans, Nilesh L. Jain, Michael G. Kahn Jan 1993

Objective Evaluation Of Radiation Treatment Plans, Nilesh L. Jain, Michael G. Kahn

All Computer Science and Engineering Research

The evaluation of radiation treatment plans involves making trade-offs among doses delivered to the tumor volumes and nearby normal tissues. Evaluating state-of-the-art three-dimensional (3D) plans is a difficult task because of the huge amount of planning data that needs to be deciphered. Multiattribute utility theory provides a methodology for specifying trade-offs and selecting the optimal plan from many competing lans. Using multiattribute utility theory, we are developing a clinically meaningful objective plan-evaluation model for 3D radiation treatment plans. Our model incorporates three of the factors involved in radiation treatment evaluation - treatment preferences of the radiation oncologist, clinical condition of …

Go to article

The N-Body Problem: Distributed System Load Balancing And Performance Evaluation, Vasudha Govindan, Mark A. Franklin Jan 1993

The N-Body Problem: Distributed System Load Balancing And Performance Evaluation, Vasudha Govindan, Mark A. Franklin

All Computer Science and Engineering Research

In this paper, the N-body simulation problem is considered, its parallel implementation described, its execution time performance is modeled and compared with measured results, and two alternative load balancing algorithms for enhancing performance investigated. Parallel N-body techniques are widely applied in various fields and possess characteristics that challenge the computation and communication capabilities of parallel computing systems and are therefore good candidates for use as parallel benchmarks. Performance models may be used to estimate the performance of an algorithm on a given system, identify performance bottlenecks and study the performance implications of several algorithm are system enhancements. In this paper, …

Go to article

The Programmers' Playground: I/O Abstraction For Heterogeneous Distributed Systems, Kenneth J. Goldman, Michael D. Anderson, Bala Swaminathan Jan 1993

The Programmers' Playground: I/O Abstraction For Heterogeneous Distributed Systems, Kenneth J. Goldman, Michael D. Anderson, Bala Swaminathan

All Computer Science and Engineering Research

I/O abstraction is offered as a new high-level approach to interprocess communication. Functional components of a concurrent system are written as encapsulated modules that act upon local data structures, some of which may be published for external use. Relationships among modules are specified by logical connections among their published data structures. Whenever a module updates published data, I/O takes place implicitly according to the configuration of logical connections. The Programmer's Playground, a software library and run-time system supporting I/O abstraction, is described. Design goals include high-level communication among programs written in multiple programming languages and the uniform treatment of discrete …

Go to article

An Optimal Nonblocking Multicast Virtual Circuit Switch, Jonathan S. Turner Jan 1993

An Optimal Nonblocking Multicast Virtual Circuit Switch, Jonathan S. Turner

All Computer Science and Engineering Research

This paper describes an architecture for a multicast virtual circuit switch using cell recycling. This is the first nonblocking switch architecture that is optimal in both the switching network complexity and the amount of memory required for multicast address translation. Furthermore, it is optimal in the amount of effort required for multicast connection modification. This architecture makes it both technically and economically feasible to construct the large switching systems that will ultimately be needed for wide scale deployment of Broadband ISDN to residential users. In particular, we estimate that systems with tens of thousands of 620 Mb/s ports can be …

Go to article

A Comparison Study Of The Pen And The Mouse In Editing Graphic Diagrams, Ajay Apte, Takayuki Dan Kimura Jan 1993

A Comparison Study Of The Pen And The Mouse In Editing Graphic Diagrams, Ajay Apte, Takayuki Dan Kimura

All Computer Science and Engineering Research

We report the results of an experiment comparing the merits of the pen and the mouse as drawing devices. For this study a pen-based graphic diagram editor equipped with a shape recognition algorithm was developed on GO's PenPoint operating system. A commercially available drawing program on NeXT was used for mouse-based editing. Twelve CS students were chosen as subjects and asked to draw four different diagrams of similar complexity: two with a pen and the other two with a mouse. The diagrams are chosen from the categories of dataflow visual language, Petri nets, flowcharts, and state diagrams. The results indicate …

Go to article

Segmentation/Recognition Of Hand-Written Numeral Characters, Khalid Sherdil Jan 1993

Segmentation/Recognition Of Hand-Written Numeral Characters, Khalid Sherdil

All Computer Science and Engineering Research

This thesis describes a number of techniques for segmenting non-cursive handwritten digits into individual characters. It strongly emphasizes on a recognition-segmentation algorithm, which uses the linear regression method to recognize those strokes which consist of one or more straight-lined parts. A new method of sampling the pen data according to the pen speed, hence giving a more uniform points concentratino distribution, is also introduced. It is shown how several of our segmenting techniques, such as relative stroke lengths, relative stroke positions, order of stroke entry, stroke direction, stroke intersection, etc. can be combined to yield success results of about 95%.

Go to article

Clocked And Asynchronous Instruction Pipelines, Mark A. Franklin, Tienyo Pan Jan 1993

Clocked And Asynchronous Instruction Pipelines, Mark A. Franklin, Tienyo Pan

All Computer Science and Engineering Research

Clocked (synchronous) and self-timed (asynchronous) represent the two prinicipal methodologies associated with timing control and synchronization of digital systems. In this paper, clocked and the asynchronous instruction pipelines are modeled and compared. The approach which yields the best performance is dependent on technology parameters, operating range and pipeline algorithm characteristics. Design curves are presented which permit selection of the best approach for a given application and technology environment.

Go to article

First Prev Next Last