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Full-Text Articles in Physical Sciences and Mathematics

Toward Scalable Parallel Software: An Active Object Model And Library To Support Von Neumann Languages, George K. Thiruvathukal Dec 1994

Toward Scalable Parallel Software: An Active Object Model And Library To Support Von Neumann Languages, George K. Thiruvathukal

Computer Science: Faculty Publications and Other Works

Scalable parallel processing has been proposed as the technology scientists and engineers can use today to solve the problems of tomorrow. Many computational Grand Challenge problems require between two and three orders of magnitude than can be provided with the scalable parallel hardware of the early nineteen-nineties. While hardware continues to become more scalable and cheaper, software is not advancing at the same pace and remains a very expensive part of systems development.

A great deal of emphasis on software technology to support scalable parallel processing is placed on von Neumann languages. One of two approaches is common: (a) augment …


Next Generation Real-Time Systems: Investigating The Potential Of Partial-Solution Tasks, Robert E. J. Caley Dec 1994

Next Generation Real-Time Systems: Investigating The Potential Of Partial-Solution Tasks, Robert E. J. Caley

Theses and Dissertations

While the cyclic executive and fixed-priority scheduling strategies have been sufficient to handle traditional real- time requirements. they are insufficient for dealing with the complexities of next-generation real-time systems. New methods of intelligent control must be developed for guaranteeing on-time task completion for real-time systems that are faced with unpredictable and dynamically changing requirements. Implementing real-time processes as partial-solution tasks is one technique that may be beneficial. This type of task. when combined with intelligent control, has the potential for increasing pre-runtime schedulability, system maintainability. and runtime robustness. This research investigates the benefits of partial-solution tasks by experimentally measuring the …


Enhanced Visual User Interface Support For Domain-Oriented Application Composition Systems, Richard A. Guinto Dec 1994

Enhanced Visual User Interface Support For Domain-Oriented Application Composition Systems, Richard A. Guinto

Theses and Dissertations

This research refined the functionality and usability of a previously developed visual interface for a domain-oriented application composition system. The refinements incorporated more sophisticated user interface design concepts1 to reduce user workload. User workload was reduced through window reordering, menu redesign, and Human Computer Interaction techniques such as; combining repetitive procedures into single commands, reusing composition information whenever possible and deriving new information from existing information. The Software Refinery environment, including its visual interface tool INTERVISTA, was used to develop techniques for visualizing and manipulating objects contained in a formal knowledge base of objects. The interface was formally validated with …


A Numerical Model To Predict The Fate Of Jettisoned Aviation Fuel, Karl D. Pfeiffer Dec 1994

A Numerical Model To Predict The Fate Of Jettisoned Aviation Fuel, Karl D. Pfeiffer

Theses and Dissertations

While airborne, military and civilian aircraft must occasionally jettison unburned aviation fuel into the atmosphere. This research investigates the fate of a jettisoned fuel (e.g. JP-4, JP-8, etc.) from initial release to final ground fall by numerically modeling the physical phenomena governing the fate of this fuel: evaporation, advection, and dispersion. Using previous work in evaporation and free fall of fuel droplets as a foundation, this thesis presents an integrated evaporation advection and dispersion model designed to run under the resources of a typical personal computer. This integrated model is capable of using near real-time meteorological data (i.e. vertical profiles …


Space Modeler: An Expanded, Distributed, Virtual Environment For Space Visualization, John C. Vanderburgh Dec 1994

Space Modeler: An Expanded, Distributed, Virtual Environment For Space Visualization, John C. Vanderburgh

Theses and Dissertations

The Space Modeler is the first truly immersive virtual environment that models the solar system, models satellites in near-Earth orbit, and can operate in a Distributed Interactive Simulation (DIS) environment. It increases the capabilities of the 1993 Satellite Modeler by expanding the physical limits of the environment and by implementing a new three-dimensional user interface. Satellite orbits are modeled using NASA two line element sets. The positions of the Sun, Moon and planets are computed using an algorithm based on planetary orbital element sets using a linear polynomial fit. For higher precision, the planetary orbits can be computed using an …


An Analysis Of Bayesian Networks As Classifiers, Gregory C. Ahlquist Dec 1994

An Analysis Of Bayesian Networks As Classifiers, Gregory C. Ahlquist

Theses and Dissertations

An analysis of Bayesian networks as classifiers is presented. This analysis results in an algorithm and several tools related to Bayesian network classifiers. The tools calculate and display the decision regions for two level Bayesian network classifiers. They collectively provide an approach to analyze the effects of changing network parameters on the network's decision regions. The algorithm defines a Bayesian network classifier to solve traditional classification problems. The algorithm is data driven, meaning that the resulting Bayesian network classifier is uniquely tuned to the classification problem at hand. Also, the algorithm contains procedures for defining the topology of a Bayesian …


Artificially Intelligent Air Combat Simulation Agents, Daniel E. Gisselquist Dec 1994

Artificially Intelligent Air Combat Simulation Agents, Daniel E. Gisselquist

Theses and Dissertations

The Advanced Research Projects Agency (ARPA), in an effort to improve military simulations, has proposed a standard for Distributed Interactive Simulation (DIS). This network protocol will allow dissimilar applications to communicate simulation information. In the field of air combat, this will allow pilots in remote simulators to fly in a common simulation. The success of this standard is dependent on applications being able to work within that standard, as well as a large variety of Computer Generated Forces (CGFs) to complement interactive forces. CGFs are needed to help simulate the large combat scenarios that can only occur in wartime. By …


Parallelization Of The 2d Roe Scheme On The Intel Paragon, John R. Graham Iii Dec 1994

Parallelization Of The 2d Roe Scheme On The Intel Paragon, John R. Graham Iii

Theses and Dissertations

This study presented a methodology for determining the general performance characteristics of a computational fluid dynamics (CFD) algorithm on the Intel Paragon. By performing a rigorous time complexity analysis of a parallel CFD algorithm, the general performance could be characterized before the code was actually parallelized. This was shown by implementing a serial version of the 2-D Roe Scheme on the Paragon. This explicit code was parallelized by the addition of generic yet efficient routines that decomposed the domain, automatically adjusted partition indices, and performed 2-D and 3-D buffer exchanges. Additionally, efficient global routines available for the Paragon were used …


Modeling Workload Effectiveness And Efficiency Of Air Force Wing Command And Control, Michael D. Sarchet Dec 1994

Modeling Workload Effectiveness And Efficiency Of Air Force Wing Command And Control, Michael D. Sarchet

Theses and Dissertations

This research investigated the feasibility of applying software engineering technology to the Air Force wing command and control (C2) domain. As part of this research, domain analysis and object-oriented techniques were investigated and a specific approach was chosen to analyze the domain. Analysis of the domain resulted in an object-oriented domain model that captured the key objects, operations, and associations of wing C2. The domain model was used to design and implement a prototype software tool that enables wing decision makers to make assessments about automation's impact on wing C2 operations.


A Correlational Study Of The Sei's Capability Maturity Model And Software Development Performance In Dod Contracts, Robert M. Flowe, James B. Thordahl Dec 1994

A Correlational Study Of The Sei's Capability Maturity Model And Software Development Performance In Dod Contracts, Robert M. Flowe, James B. Thordahl

Theses and Dissertations

The Software Engineering Institute's (SEl's) Capability Maturity Model (CMM) is to measure an organization's software development process maturity. The Department of Defense (DoD) has model with the belief that a more mature software development process will result in a more successful software subject. Although there is a growing body of anecdotal evidence supporting this presumed correlation, there is empirical evidence. Thus, the goal of our research was to determine the nature of the correlation, if any, :ware process maturity and software project success, where process maturity is based on a CMM rating and success based on the parameters of cost …


Factors In Human-Computer Interface Design (A Pilot Study), Susan Stewart Dec 1994

Factors In Human-Computer Interface Design (A Pilot Study), Susan Stewart

Theses and Dissertations

The DoD has budgeted over $9.8 billion for 1995 for information technology, yet many government office workers let their existing systems sit idle. This thesis explores why these computers are sitting idle. This researcher's initial hypothesis was that certain features of the human-computer interface can positively or negatively affect efficiency, retention, and satisfaction level of workers. Although some research is being done in this area, interfaces continue to be of poor quality, especially in the DoD, where long procurement cycles, forced purchases, and limited budgets result in out-of-date software. Intuitively most programmers know the human-computer interface impacts on a person's …


Embedology And Neural Estimation For Time Series Prediction, Robert E. Garza Dec 1994

Embedology And Neural Estimation For Time Series Prediction, Robert E. Garza

Theses and Dissertations

Time series prediction has widespread application, ranging from predicting the stock market to trying to predict future locations of scud missiles. Recent work by Sauer and Casdagli has developed into the embedology theorem, which sets forth the procedures for state space manipulation and reconstruction for time series prediction. This includes embedding the time series into a higher dimensional space in order to form an attractor, a structure defined by the embedded vectors. Embedology is combined with neural technologies in an effort to create a more accurate prediction algorithm. These algorithms consist of embedology, neural networks, Euclidean space nearest neighbors, and …


Knowledge-Based Safety Training System (Kbsts): A Prototype Implementation, Venky Shankararaman, B. S. Lee Dec 1994

Knowledge-Based Safety Training System (Kbsts): A Prototype Implementation, Venky Shankararaman, B. S. Lee

Research Collection School Of Computing and Information Systems

A computer-based safety training system for process operators must be able to make effective presentation of textual material, test the trainee's understanding through quizzes and facilitate plant simulation. The general framework of such a system is presented in an earlier paper (Computers in Industry, Vol. 17, 1991, pp. 349–358). In this paper, we discuss the development and implementation of a prototype Knowledge-Based Safety Training System based on the framework. The design philosophy, system architecture and the plant modelling methodology are described.


The Fat-Pyramid And Universal Parallel Computation Independent Of Wire Delay, Ronald I. Greenberg Dec 1994

The Fat-Pyramid And Universal Parallel Computation Independent Of Wire Delay, Ronald I. Greenberg

Computer Science: Faculty Publications and Other Works

This paper shows that a fat-pyramid of area Θ(A) requires only O(log A) slowdown to simulate any competing network of area A under very general conditions. The result holds regardless of the processor size (amount of attached memory) and number of processors in the competing networks as long as the limitation on total area is met. Furthermore, the result is valid regardless of the relationship between wire length and wire delay. We especially focus on elimination of the common simplifying assumption that unit time suffices to traverse a wire regardless of its length, since the assumption becomes more and more …


Transportable Agents, Keith D. Kotay, David Kotz Dec 1994

Transportable Agents, Keith D. Kotay, David Kotz

Dartmouth Scholarship

As network information resources grow in size, it is often most efficient to process queries and updates at the site where the data is located. This processing can be accomplished by using a traditional client-server network interface, which constrains the client to the set of queries supported by the server, or requires the server to send all data to the client for processing. The former is inflexible; the latter is inefficient. Transportable agents, which support the movement of the client computation to the location of the remote resource, have the potential to be more flexible and more efficient. Transportable agents …


Topologies Invariant Under A Group Action, Paul Bankston Dec 1994

Topologies Invariant Under A Group Action, Paul Bankston

Mathematics, Statistics and Computer Science Faculty Research and Publications

We study links between faithful group actions on a set and topologies on that set. In one direction, a group action has its invariant topologies (so we may regard members of the action to be homeomorphisms relative to those topologies); in the other direction, a topology has its preserving group actions (i.e., the subgroups of the homeomorphism group of the topology). This two-way passage allows us to discuss topological features of group actions as well as symmetry features of topologies.


Autonomous Robot Navigation In Unknown Terrains Using Parallel Numerical Artificial Potential Fields, John C. Schneider Dec 1994

Autonomous Robot Navigation In Unknown Terrains Using Parallel Numerical Artificial Potential Fields, John C. Schneider

Computer Science Theses & Dissertations

We present a new artificial potential field formulation for resolution complete robot navigation that unifies the purely geometric path planning problem with the lower level force control problem. Our formulation is designed for numerical computation over a massively parallel mesh of processors and is responsive to newly discovered terrain features. It does not suffer from many of the problems commonly associated with potential fields and with adequate resolution provides provably correct, collision free convergence to the goal. In addition, our formulation supports many desirable, practical features required for implementation, such as bounded actuator torques, attainable incremental constructability, realizable computation and …


Semantics Vs. Syntax Vs. Computations Machine Models For Type-2 Polynomial-Time Bounded Functionals (Preliminary Draft), James S. Royer Nov 1994

Semantics Vs. Syntax Vs. Computations Machine Models For Type-2 Polynomial-Time Bounded Functionals (Preliminary Draft), James S. Royer

Electrical Engineering and Computer Science - Technical Reports

This paper investigates analogs of the Kreisel-Lacombe-Shoenfield Theorem in the context of the type-2 basic feasible functionals, a.k.a. the Mehlhorn-Cook class of type-2 polynomial-time functionals. We develop a direct, polynomial-time analog of effective operation, where the time bound on computations is modeled after Kapron and Cook's scheme for their basic polynomial-time functionals. We show that (i) if P = NP, these polynomial-time effective operations are strictly more powerful on R (the class of recursive functions) than the basic feasible functions, and (ii) there is an oracle relative to which these polynomial-time effective operations and the basic feasible functionals have the …


A Case Tool Supporting The Moses Development Methodology, Florida International University Glupe Nov 1994

A Case Tool Supporting The Moses Development Methodology, Florida International University Glupe

FIU Electronic Theses and Dissertations

A new breed of CASE tools is taking advantage of object-oriented development. The CASE tool in this thesis will serve as a top-level guidance platform. The user will be able to follow an agenda in which his progress is recorded for each step of the development process. At the same time, the user will still be able to develop documents, diagrams and source code by using provided editors. The specific object-oriented methodology followed in this thesis is MOSES (Methodology for Object-Oriented Software Engineering of Systems). This advocates an iterative approach to development while providing both textual and graphical deliverables to …


Mccolm’S Conjecture, Yuri Gurevich, Neil Immerman, Saharon Shelah Nov 1994

Mccolm’S Conjecture, Yuri Gurevich, Neil Immerman, Saharon Shelah

Neil Immerman

Gregory McColm conjectured that positive elementary inductions are bounded in a class K of finite structures if every (FO + LFP) formula is equivalent to a first-order formula in K. Here (FO + LFP) is the extension of first-order logic with the least fixed point operator. We disprove the conjecture. Our main results are two model-theoretic constructions, one deterministic and the other randomized, each of which refutes McColm’s conjecture.


Multiprocessor Document Allocation: A Neural Network Approach, Abdulaziz Sultan Al-Sehibani, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka Nov 1994

Multiprocessor Document Allocation: A Neural Network Approach, Abdulaziz Sultan Al-Sehibani, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka

Electrical Engineering and Computer Science - Technical Reports

We consider the problem of distributing the documents to a given set of processors so that the load on each processor is as equal as possible and the amount of communication is as small as possible. This is an NP-Complete problem. We apply continuous as well as discrete Hopfield neural networks to obtain suboptimal solutions for the problem. These networks perform better than a genetic algorithm for this task proposed by Frieder et al. [4]; in particular, the continuous Hopfield network performs extremely well.


1.1, Yolanda Jones Nov 1994

1.1, Yolanda Jones

E-lert

No abstract provided.


Disk-Directed I/O For Mimd Multiprocessors, David Kotz Nov 1994

Disk-Directed I/O For Mimd Multiprocessors, David Kotz

Computer Science Technical Reports

Many scientific applications that run on today's multiprocessors are bottlenecked by their file I/O needs. Even if the multiprocessor is configured with sufficient I/O hardware, the file-system software often fails to provide the available bandwidth to the application. Although libraries and improved file-system interfaces can make a significant improvement, we believe that fundamental changes are needed in the file-server software. We propose a new technique, disk-directed I/O, that flips the usual relationship between server and client to allow the disks (actually, disk servers) to determine the flow of data for maximum performance. Our simulations show that tremendous performance gains are …


A Data-Parallel Programming Library For Education (Dapple), David Kotz Nov 1994

A Data-Parallel Programming Library For Education (Dapple), David Kotz

Computer Science Technical Reports

In the context of our overall goal to bring the concepts of parallel computing into the undergraduate curriculum, we set out to find a parallel-programming language for student use. To make it accessible to students at all levels, and to be independent of any particular hardware platform, we chose to design our own language, based on a data-parallel model and on C++. The result, DAPPLE, is a C++ class library designed to provide the illusion of a data-parallel programming language on conventional hardware and with conventional compilers. DAPPLE defines Vectors and Matrices as basic classes, with all the usual C++ …


Icdm: Integrated Cooperative Decision Making - In Practice, Leonard Myers, Jens G. Pohl Nov 1994

Icdm: Integrated Cooperative Decision Making - In Practice, Leonard Myers, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

Multi-agent systems provide an attractive architecture for the implementation of complex systems. Much of the research is focussed on complete automation of the decision making process as a means of duplicating human abilities for working with new problems and environments. There as also a need for systems that employ the human as an agent and rely on human abilities for common sense and deep thought. The CAD Research Center at Cal Poly and CDM Technologies have significant experience in building systems of the latter type that assist human users in solving complex problems in planning, design and economics. This experience …


Multimedia Authoring, Development Environments, And Digital Video Editing, Fillia Makedon, James W. Matthews, Charles B. Owen, Samuel A. Rebelsky Nov 1994

Multimedia Authoring, Development Environments, And Digital Video Editing, Fillia Makedon, James W. Matthews, Charles B. Owen, Samuel A. Rebelsky

Dartmouth Scholarship

Multimedia systems integrate text, audio, video, graphics, and other media and allow them to be utilized in a combined and interactive manner. Using this exciting and rapidly developing technology, multimedia applications can provide extensive benefits in a variety of arenas, including research, education, medicine, and commerce. While there are many commercial multimedia development packages, the easy and fast creation of a useful, full-featured multimedia document is not yet a straightforward task.

This paper addresses issues in the development of multimedia documents, ranging from user-interface tools that manipulate multimedia documents to multimedia communication technologies such as compression, digital video editing and …


Devious: A Distributed Environment For Vision Tasks, Phillip R. Romig Iii, Ashok K. Samal Nov 1994

Devious: A Distributed Environment For Vision Tasks, Phillip R. Romig Iii, Ashok K. Samal

CSE Conference and Workshop Papers

We present a system for the integration of computer vision tasks in a distributed environment. This system, called DeViouS, is based on the client/server model and runs in a heterogeneous environment of Unix workstations. It takes advantage of the free cycles in modern workstation environments to distribute and speed up the execution of vision tasks.

Two primary goals of DeViouS are to provide a practical distributed system and a research environment for vision computing. DeViouS is based on a modular design that allows experimentation in various aspects of algorithm design, scheduling and network programming. It can make use of any …


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 10, Number 9, November 1994, College Of Engineering And Computer Science, Wright State University Nov 1994

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 10, Number 9, November 1994, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A fourteen page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.


Characterization Of A Class Of Sigmoid Functions With Applications To Neural Networks, Anil Ravindran Menon, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka Nov 1994

Characterization Of A Class Of Sigmoid Functions With Applications To Neural Networks, Anil Ravindran Menon, Kishan Mehrotra, Chilukuri K. Mohan, Sanjay Ranka

Electrical Engineering and Computer Science - Technical Reports

Sigmoid functions, whose graphs are "S-shaped" curves, appear in a great variety of contexts, such as the transfer functions in many neural networks. Their ubiquity is no accident; these curves are the among the simplest non-linear curves, striking a graceful balance between linear and non-linear behavior.


Covering Radius 1985-1994, G. D. Cohen, S. N. Litsyn, Antoine C. Lobstein, H. F. Mattson Jr Nov 1994

Covering Radius 1985-1994, G. D. Cohen, S. N. Litsyn, Antoine C. Lobstein, H. F. Mattson Jr

Electrical Engineering and Computer Science - Technical Reports

We survey important developments in the theory of covering radius during the period 1985-1994. We present lower bounds, constructions and upper bounds, the linear and nonlinear cases, density and asymptotic results, normality, specific classes of codes, covering radius and dual distance, tables, and open problems.