Computer Sciences Commons^™

A Methodology For Developing Correct Rule-Based Programs For Parallel Implementation, Rosanne Fulcomer Gamble

All Computer Science and Engineering Research

Production systems, also called rule-based systems, are very useful in automating certain human expert tasks, but the current technology exhibits many problems. We believe that parallelism is difficult to exploit in production system programs for two reasons. First, the original serial programs are designed with a priori knowledge of an explicit global control mechanism which must be simulated for correct execution in parallel. The second reason for the difficulty is that no formal language exists in which to express these programs and no verification techniques are utilized to prove properties which guarantee correct execution in parallel. With these two obstacles …

The Display And Manipulation Of Temporal Information, Steve B. Cousins, Michael G. Kahn Washington University In St. Louis, Mark E. Frisse Washington University In St. Louis

All Computer Science and Engineering Research

Because medical data have complex temporal features, special techniques are required for storing, retrieving, and displaying clinical data from electronic databases. One significant problem caused by the temporal nature of medical data has been called the temporal granularity problem. The temporal granularity problem is said to occur when the set of facts relevant to a specific problem changes as the time scale changes. We argue that what is needed to deal with changes in the relevant time scale are temporal granularity heuristics. One heuristic that we have explored is that, for any level of problem abstraction, and for each type …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, November 1989, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, October 1989, 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.

Optical Machine Recognition Of Lower-Case Greek Characters Of Any Size, Ivan X. D. D'Cunha

Electrical & Computer Engineering Theses & Dissertations

An algorithm utilizing a syntactic approach and a criterion based on normalized moments is defined for the reliable, automatic, machine recognition of handwritten and printed Greek characters of any size and font. In this approach a binary image of the character in question is obtained initially; its skeleton is then produced by utilizing a standard thinning algorithm. The classification process then incorporates the topological features of the characters such as existence of closed curves, number of intersections, number and location of free ends, axial symmetry, and the criteria derived from normalized moments to uniquely identify each pattern. Experiments conducted demonstrated …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, September 1989, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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

Axon: Application-Oriented Lightweight Transport Protocol Design, James P.G. Sterbenz, Gurudatta M. Parulkar

All Computer Science and Engineering Research

This paper describes the application-oriented lightweight transport protocol for object transfer (ALTP-OT) in the Axon host communication architecture for distributed applications. The Axon Project is investigating an integrated design of host architecture, operating systems, and communication protocols to allow the utilization of the high band-width provided by the next generation of communication networks. ALTP-OT provides the end-to-end transport of segment and message objects for interprocess communication across a very high speed internetwork, supporting demanding applications such as scientific visualization and imaging. ALTP-OT uses rate-based flow control specifically oriented to the transfer of objects directly between application memory spaces. This document …

A Mathematical Treatment Of Defeasible Reasoning And Its Implementation, Guillermo R. Simari, R. P. Loui

All Computer Science and Engineering Research

We present a mathematical approach to defeasible reasoning. This approach is based on the notion of specificity introduced by Poole and the theory of warrant presented by Pollock. We combine the ideas of the two. This main contribution of this paper is a precise well-defined system which exhibits correct behavior when applied to the benchmark examples in the literature. We prove that an order relation can be introduced among equivalence classes under the equi-specificity relation. We also prove a theorem that ensures the termination of the process of finding the justified facts. Two more lemmas define a reduced search space …

Axon: A High Speed Communication Architecture For Distributed Applications, James P.G. Sterbenz, Gurudatta M. Parulkar

All Computer Science and Engineering Research

There are two complementary trends in the computer and communication fields. Increasing processor power and memory availability allow more demanding applications, such as scientific visualization and imaging. Advances in network performance and functionality have the potential for supporting programs requiring high bandwidth and predictable performance. However, the bottleneck in increasingly in the host-network interface, and thus the ability to deliver high performance communication capability to applications has not kept up with the advances in computer and network speed. We have proposed a new architecture that meets these challenges called Axon, whose novel aspects include: an integrated design of hardware, operating …

Efficient Interconnection Schemes For Vlsi And Parallel Computation, Ronald I. Greenberg

Computer Science: Faculty Publications and Other Works

This thesis is primarily concerned with two problems of interconnecting components in VLSI technologies. In the first case, the goal is to construct efficient interconnection networks for general-purpose parallel computers. The second problem is a more specialized problem in the design of VLSI chips, namely multilayer channel routing. In addition, a final part of this thesis provides lower bounds on the area required for VLSI implementations of finite-state machines. This thesis shows that networks based on Leiserson's fat-tree architecture are nearly as good as any network built in a comparable amount of physical space. It shows that these "universal" networks …

Ampliative Inference, Computation, And Dialectic, R. P. Loui

All Computer Science and Engineering Research

There are three theses here: • Non-computationally conceived inference merely expands notation. This includes induction as well as deduction, and thus both deserve the adjective non-ampliative. Deriving entailments merely expands shorthand. All of the familiar formalisms for reasoning do just this. • There now exist examples of formalism for reasoning that do something else. They are deliberative, and to say in what way they are deliberative requires reference to the process through which they compute their entailments. • The original ampliative/non-ampliative terminology best survives as referring to this new distinction. Viewed formally, all other attempted distinctions either presume deduction to …

Host-Network Interface Architecture For Gigabit Communications, James P. G. Sterbenz

All Computer Science and Engineering Research

There are two complementary trends in the computer and communications fields. Increasing processor power and memory availability allow more demanding applications, such as scientific visualizations and imaging. Advances in network performance and functionality have the potential for supporting applications requiring high bandwidth communications. However, the bottleneck is increasingly in the host-network interface, and thus the ability to deliver high performance communications capability to applications has not kept up with the advance in computer and network speed. We have proposed a new architecture that meets these challenges, called Axon. The Axon thesis is that an essential requirement for the support of …

Back Propagation With Integer Arithmetic, Takayuki Dan Kimura

All Computer Science and Engineering Research

The present work investigates the significance of arithmetic precision in neural network simulation. Noting that a biological brain consists of a large number of cells of low precision, we try to answer the question: With a fixed size of memory and CPU cycles available for simulation, does a larger sized net with less precision perform better than smaller sized one with higher precision? We evaluate the merits and demerits of using low precision integer arithmetic in simulating backpropagation networks. Two identical backpropagation simulators, ibp and fbp, were constructed on Mac II, ibp with 16 bits integer representations of network parameters …

User's Manual For Ccrc: (Common Lisp Version) Computing Reference Classes Statistical Reasoning Shell V. 2.5, R. P. Loui

All Computer Science and Engineering Research

CCRC implements a subset of Kyburg's rules for statistical inference. The system states from 1961 and is briefly described in "The Reference Class," (H. Kyburg Philosophy of Science 50, 1982). Consult the paper "Computing Reference Classes" (R. Loui, in Kanal, L. and Lemmer, J., Uncertainty in AI, v.1, North-Holland 1987) for a precis of the ideas underlying this program. This document is only the skeleton of a manual. It is designed to get the novice on the program as quickly as possible, and to provide some guidance for advanced questions. This piece of software is the extended version of a …

Defeasible Decisions: What The Proposal Is And Isn't, R. P. Loui

All Computer Science and Engineering Research

In two recent papers, I have proposed a description of decision analysis that differs from the Bayesian picture painted by Savage, Jeffrey and other classic authors. Response to this view have been either overly enthusiastic or unduly pessimistic. In this paper I try to place the idea in its proper place, which must be somewhere in between. Looking at decision analysis as defeasible reasoning produces a framework in which planning and decision theory can be integrated, but work on the details has barely begun. It also produces a framework in which the meta-decision regress can be stopped in a reasonable …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, May 1989, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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

Data Reduction Procedure For An Experimental Method Of Measuring The Velocity-Coupled Response Function Of Solid Propellants, William H. Jarvis

Master's Theses - Daytona Beach

A computer program has been developed for calculation of the velocity-coupled response function of solid-propellants from experimentally measured pressure data. The proposed velocity-coupled response function measurement apparatus consists of an end-burner combustor where the propellant sample is oscillated in a direction normal to the flow in the presence of a standing acoustic wave within the combustion chamber. The pressure measurements are made at select points along the length of the chamber.

The data reduction program consists of a Runge-Kutta routine driven by a BFGS multivariable search routine. The Runge-Kutta routine determines the pressure distribution within the chamber of the proposed …

Performance Modeling And Enhancement For The Atamm Data Flow Architecture, Sukhamoy Som

Electrical & Computer Engineering Theses & Dissertations

Algorithm To Architecture Mapping Model (ATAMM) is a new marked graph model from which the rules for data and control flow in a homogeneous, multicomputer, data flow architecture may be defined. This research is concerned with performance modeling and performance enhancement for periodic execution of large-grain, decision-free algorithms in such an ATAMM defined architecture. Performance measures and bounds are established. Algorithm transformation techniques are identified for performance enhancement and reduction of computing element requirements. Operating strategies are developed for optimum time performance and for sub-optimum time performance under limited availability of computing elements. An ATAMM simulator is used to test …

Efficient Multi-Layer Channel Routing, Ronald I. Greenberg

Computer Science: Faculty Publications and Other Works

No abstract provided.

Model-Based Interpretation Of Time-Varying Medical Data, Michael G. Kahn, Lawrence M. Fagan Washington University In St. Louis, Lewis B. Sheiner Washington University In St. Louis

All Computer Science and Engineering Research

Temporal concepts are critical is medical therapy-planning. If given early enough, specific therapeutic choices may abort or suppress evolving undesired changes in a patient’s clinical status. Effective medical decision making demands recognition and interpretation of complex temporal changes that permeate the medical record. This paper presents a methodology for representing and using medical knowledge about temporal relationships to infer the presence of clinically relevant events, and describes a program, called TOPAZ, that uses this methodology to generate a narrative summary of such events. A unique feature of TOPAZ is the use of numeric and symbolic modeling techniques to perform temporal …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, March 1989, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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

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 …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, February 1989, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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

A Psychophysical Comparison Of Two Methods For Adaptive Histogram Equalization, John B. Zimmerman, Steve B. Cousins, Mark E. Frisse, Karin M. Hartzell, Michael C. Kahn

All Computer Science and Engineering Research

Adaptive histogram equalization (ahe) is a method for adaptive contrast enhancement of digital images propped by Pizer et. Al.. It has the properties that it is an automatic, reproducible method for the simultaneous viewing of contrast within a digital image with a large dynamic range. Recent experiments have show that in specific cases, there is no significant difference in the ability of ahe and linear intensity windowing to display grey-scale contrast. More recently, Pizer et al. have proposed a variant of ahe which limits the allowed contrast enhancement of the image. The contrast-limited adaptive histogram equalization (clahe) produces images in …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, January 1989, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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

An Inexpensive Electronic Viewbox, J. R. Cox Jr., R. G. Jost, T. Monsees, S. Ramamurthy, M. Karlsson

All Computer Science and Engineering Research

An "electronic viewbox" is described that has been designed to meet the demand for a modestly priced soft-copy display for radiology. Issues associated with spatial resolution, intensity resolution, image magnification, user interface, digital communications and possible applications are discussed.

Determinism And Connectionism In A Rule-Based Natural Language System, Stan C. Kwasny, Kanaan A. Faisal

All Computer Science and Engineering Research

The processing of Natural Language is, at the same time, natural symbolic and naturally symbolic and naturally sub-symbolic. It is symbolic because ultimately symbols play a critical role. Writing systems, for example, owe their existence to the symbolic nature of language. It is also sub-symbolic because of the nature of speech, the fuzziness of concepts, and the high degree of parallelism that is difficult to explain as a purely symbolic phenomenon. This report details a set of experiments which support the claim that Natural Language can be syntactically processed in a robust manner using a connectionist deterministic parser. The model …

The Next Generation Of Internetworking, Gurudatta M. Parulkar

All Computer Science and Engineering Research

This paper describes a research effort concerned with the design of the next generation of internet architecture, which has been necessitated by two emerging trends. First, there will be at least a few orders of magnitude increase in data rates of communication networks in the next few years. For example, researchers are already prototyping networks with data rates of up to a few hundred Mbps, and are planning networks with data rates up to a few Gbps. Second, researchers from all disciplines of science, engineering, and humanities plan to use the communication infrastructure to access widely distributed resources in order …

Randomized Routing On Fat-Trees, Ronald I. Greenberg, Charles E. Leiserson

Computer Science: Faculty Publications and Other Works

Fat-trees are a class of routing networks for hardware-efficient parallel computation. This paper presents a randomized algorithm for routing messages on a fat-tree. The quality of the algorithm is measured in terms of the load factor of a set of messages to be routed, which is a lower bound on the time required to deliver the messages. We show that if a set of messages has load factor lambda on a fat-tree with n processors, the number of delivery cycles (routing attempts) that the algorithm requires is O(lambda + lg n lg lg n) with probability 1-O(1/n). The best previous …

Lower Bounds On The Area Of Finite-State Machines, M. J. Foster, Ronald I. Greenberg

Computer Science: Faculty Publications and Other Works

There are certain straightforward algorithms for laying out finite-state machines. This paper shows that these algorithm are optimal in the worst case for machines with fixed alphabets. That is, for any s and k, there is a deterministic finite-state machine with s states and k symbols such that any layout algorithm requires Ω(ks log s) area to lay out its realization. Similarly, any layout algorithm requires Ω(ks^2) area in the worst case for nondeterministic finite-state machines with s states and k symbols.