Computer Engineering Commons^™

Improving The Run Time Of The Decomposition Algorithm For Fault Tolerant Clos Interconnection Networks Through Swap Re-Ordering, Andrea Laura Mcmakin

Theses

Clos interconnection networks, used in data networks and computing systems, can contain extra switches to be used in faulty conditions. The speed of such fault tolerant Clos interconnection networks is improved through the use these switches in no-fault situations. The network can be represented by a matrix, which is then decomposed using an algorithm, and the switch settings are thus assigned.

The original decomposition algorithm consisted of four element swaps in the following order: wild swap, simple swap, next simple swap, and successive swap. However, by re-arranging these swaps with the simple swap first, followed by the next simple and …

Possible New Directions In Mathematical Foundations Of Fuzzy Technology: A Contribution To The Mathematics Of Fuzzy Theory, Hung T. Nguyen, Vladik Kreinovich

Departmental Technical Reports (CS)

No abstract provided.

Uncertainty Representation Explains And Helps Methodology Of Physics And Science In General, Misha Kosheleva, Vladik Kreinovich, Hung T. Nguyen, Bernadette Bouchon-Meunier

Departmental Technical Reports (CS)

No abstract provided.

How To Describe Partially Ordered Preferences: Mathematical Foundations, Olga Kosheleva, Vladik Kreinovich, Hung T. Nguyen, Bernadette Bouchon-Meunier

Departmental Technical Reports (CS)

No abstract provided.

Cooperative Learning Is Better: Explanation Using Dynamical Systems, Fuzzy Logic, And Geometric Symmetries, Vladik Kreinovich, Edye Johnson-Holubec, Leonid K. Reznik, Misha Kosheleva

Departmental Technical Reports (CS)

No abstract provided.

Towards Formalization Of Feasibility, Randomness, And Commonsense Implication: Kolmogorov Complexity, And The Necessity Of Considering (Fuzzy) Degrees, Vladik Kreinovich, Luc Longpre, Hung T. Nguyen

Departmental Technical Reports (CS)

No abstract provided.

Towards Combining Fuzzy And Logic Programming Techniques, Hung T. Nguyen, Vladik Kreinovich, Daniel E. Cooke, Luqi, Olga Kosheleva

Departmental Technical Reports (CS)

No abstract provided.

From Semi-Heuristic Fuzzy Techniques To Optimal Fuzzy Methods: Mathematical Foundations And Applications, Vladik Kreinovich

Departmental Technical Reports (CS)

Fuzzy techniques have been successfully used in various application areas ranging from control to image processing to decision making. In all these applications, there is usually:

a general idea, and then

there are several possible implementations of this idea; e.g., we can use:

different membership functions,

different "and" and "or" operations,

different defuzzifications, etc.

In the first approximation, the results are usually reasonably robust and independent on this choice, so any heuristic or semi-heuristic choice works OK. However:

if we want to further improve the semi-heuristic "good enough" control or image processing techniques,

we must actually make the selection that …

Complex Problems: Granularity Is Necessary, Granularity Helps, Oscar N. Garcia, Vladik Kreinovich, Luc Longpre, Hung T. Nguyen

Departmental Technical Reports (CS)

No abstract provided.

Synthetic Files: Enabling Low-Latency File I/O For Qos-Adaptive Applications, Dylan Mcnamee, Dan Revel, Calton Pu, David Steere, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Files are a tried and true operating system abstraction. They present a simple byte-stream model of I/O that has proven intuitive for application programmers and efficient for operating system builders. However, current file systems do not provide good support for adaptive continuous media (CM) applications - an increasingly important class of applications that exhibit complex access patterns and are particularly sensitive to variations in I/O performance. To address these problems we propose synthetic files. Synthetic files are specialized views of underlying regular files, and convert complex file access patterns into simple sequential synthetic file access patterns. Synthetic file construction can …

Architectural Optimization Of Digital Libraries, Aileen O. Biser

Computer Science Theses & Dissertations

This work investigates performance and scaling issues relevant to large scale distributed digital libraries. Presently, performance and scaling studies focus on specific implementations of production or prototype digital libraries. Although useful information is gained to aid these designers and other researchers with insights to performance and scaling issues, the broader issues relevant to very large scale distributed libraries are not addressed. Specifically, no current studies look at the extreme or worst case possibilities in digital library implementations. A survey of digital library research issues is presented. Scaling and performance issues are mentioned frequently in the digital library literature but are …

Scalar Quark Searches In E+E- Collisions At √S = 181 - 184 Gev, Barate, R.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

Searches for scalar top, scalar bottom and degenerate scalar quarks have been performed with data collected with the ALEPH detector at LEP. The data sample consists of 57 pb−1 taken at s = 181–184 GeV. No evidence for scalar top, scalar bottom or degenerate scalar quarks was found in the channels t̃→cχ, t̃→bℓν̃, b̃→bχ, and q̃→qχ. From the channel t̃→cχ a limit of 74 GeV/c2has been set on the scalar top quark mass, independent of the mixing angle. This limit assumes a mass difference between the t̃ and the χ in the range 10–40 GeV/c2. From the channel t̃→bℓν̃ the …

Beyond Interval Systems: What Is Feasible And What Is Algorithmically Solvable?, Vladik Kreinovich

Departmental Technical Reports (CS)

In many real-life applications of interval computations, the desired quantities appear (in a good approximation to reality) as a solution to a system of interval linear equations. It is known that such systems are difficult to solve (NP-hard) but still algorithmically solvable. If instead of the (approximate) interval linear systems, we consider more realistic (and more general) formulations, will the corresponding problems still be algorithmically solvable? We consider three natural generalizations of interval linear systems: to conditions which are more general than linear systems, to multi-intervals instead of intervals, and to dynamics (differential and difference equations) instead of statics (linear …

Kolmogorov Complexity Justifies Software Engineering Heuristics, Ann Q. Gates, Vladik Kreinovich, Luc Longpre

Departmental Technical Reports (CS)

The "clean bill of health" produced by such a technique does not guarantee that the program is actually correct. In this paper, we show that several heuristic techniques for software testing that have been developed in software engineering can be rigorously justified. In this justification, we use Kolmogorov complexity to formalize the terms "simple" and "random" that these techniques use. The successful formalization of simple heuristics is a good indication that Kolmogorov complexity may be useful in formalizing more complicated heuristics as well.

Quality Of Service Semantics For Multimedia Database Systems, Jonathan Walpole, Charles Krasic, Ling Liu, David Maier, Calton Pu, Dylan Mcnamee, David Steere

Computer Science Faculty Publications and Presentations

Quality of service (QoS) support has been a hot research topic in multimedia databases, and multimedia systems in general, for the past several years. However, there remains little consensus on how QoS support should be provided. At the resource-management level, systems designers are still debating the suitability of reservation- based versus adaptive QoS management. The design of higher system layers is less clearly understood, and the specification of QoS requirements in domain-specific terms is still an open research topic. To address these issues, we propose a QoS model for multimedia databases. The model covers the specification of user-level QoS preferences …

The Cluster Multipole Algorithm For Far-Field Computations, Rakesh R. Patel

Electrical & Computer Engineering Theses & Dissertations

Computer simulations of N-body systems are beneficial to study the overall behavior of a number of physical systems in fields such as astrophysics, molecular dynamics, and computational fluid dynamics. A new approach for computer simulations of N-body systems is proposed in this research. The new algorithm is called the Cluster Multipole Algorithm (CMA). The goals of the new algorithm are to improve the applicability to non-point sources and to provide more control on the accuracy over current algorithms. The algorithm is targeted to applications that do not require rebuilding the data structure about the system every time step due to …

Experimental Investigations Of Wavelength And Angular Errors In Holographic Gratings With Non-Bragg-Matched Read Beams, Monish Ranjan Chatterjee, Vivek Ray

Electrical and Computer Engineering Faculty Publications

Perfect Bragg matching is generally desirable for accurate optical interconnections with holographic gratings. In reality, however, gratings may be illuminated by READ beams with non-Bragg-matched angles, or wavelengths, or both. In such cases, the scattered beams are generally misdirected, and may suffer loss of efficiency and possibly more serious errors such as crosstalk noise or missed connections. A conventional wave-vector triad method of analyzing the scattered beam errors leads readily to near-Bragg estimates of the output angular misalignment. However, the READ wave-vector triads appear to indicate a possible wavelength shift in the output beam even with a Bragg-matched READ wavelength, …

Multiple Streams Synchronization In Collaborative Multimedia Systems, Emilia Stoica

Computer Science Theses & Dissertations

With the recent increase of the communication bandwidth and processor power, new types of applications have emerged. Among them, there are multimedia application, in which users are able to control, combine, and manipulate different types of media, such as text, sound, video, computer graphics, and animation. A key requirement in any multimedia application is to synchronize the delivery of various media streams to the user. To achieve this, the sender has to provide the temporal relations between the streams as they are captured. Since the receiver uses this information in streams presentation, its accuracy is very important.

Our main contribution …

System And Method For Performing Optical Code Division Multiple Access Communication Using Bipolar Codes, James F. Young, Benhaam Aazhnag, Lim Nguyen

Department of Electrical and Computer Engineering: Faculty Publications

An optical encoding and decoding system which performs code-division multiple access (CDMA) communication in the incoherent, or direct detection, optical domain using bipolar +1/-1 codes. The present invention uses code modu lation and detection principles that permit all-optical imple mentation of the bipolar. +1/-1. code and correlation detec tion that have been developed for the radio frequency (RF) systems. This is possible in spite of the non-negative, or unipolar, +1/0, nature of the incoherent optical system that only detects and processes the signal intensity. The unipolar optical system of the present invention is equivalent to the bipolar RF system in …

Multi-Spectral Inverse Problems In Satellite Image Processing, Scott A. Starks, Vladik Kreinovich

Departmental Technical Reports (CS)

Satellite imaging is nowadays one of the main sources of geophysical and environmental information. It is, therefore, extremely important to be able to solve the corresponding inverse problem: reconstruct the actual geophysics- or environment-related image from the observed noisy data.

Traditional image reconstruction techniques have been developed for the case when we have a single observed image. This case corresponds to a single satellite photo. Existing satellites (e.g., Landsat) take photos in several (up to 7) wavelengths. To process this multiple-spectral information, we can use known reasonable multi-image modifications of the existing single-image reconstructing techniques. These modifications, basically, handle each …

Fair Division Under Interval Uncertainty, Ronald R. Yager, Vladik Kreinovich

Departmental Technical Reports (CS)

It is often necessary to divide a certain amount of money between n participants, i.e., to assign, to each participant, a certain portion w(i)>=0 of the whole sum (so that w(1)+...+w(n)=1). In some situations, from the fairness requirements, we can uniquely determine these "weights" w(i). However, in some other situations, general considerations do not allow us to uniquely determine these weights, we only know the intervals [w-(i),w+(i)] of possible fair weights. We show that natural fairness requirements enable us to choose unique weights from these intervals; as a result, we present an algorithm for fair division under interval uncertainty.

Kolmogorov Complexity, Statistical Regularization Of Inverse Problems, And Birkhoff's Formalization Of Beauty, Vladik Kreinovich, Luc Longpre, Misha Kosheleva

Departmental Technical Reports (CS)

Most practical applications of statistical methods are based on the implicit assumption that if an event has a very small probability, then it cannot occur. For example, the probability that a kettle placed on a cold stove would start boiling by itself is not 0, it is positive, but it is so small, that physicists conclude that such an event is simply impossible.

This assumption is difficult to formalize in traditional probability theory, because this theory only describes measures on sets (e.g., for an inverse problem, on the set of all functions) and does not allow us to divide functions …

Case Study Of Non-Linear Inverse Problems: Mammography And Non-Destructive Evaluation, Olga Kosheleva, S. Cabrera, Roberto A. Osegueda, Carlos M. Ferregut, Soheil Nazarian, M. J. George, Vladik Kreinovich, K. Worden

Departmental Technical Reports (CS)

The inverse problem is usually difficult because the signal (image) that we want to reconstruct is weak. Since it is weak, we can usually neglect quadratic and higher order terms, and consider the problem to be linear. Since the problem is linear, methods of solving this problem are also, mainly, linear (with the notable exception of the necessity to take into consideration, e.g., that the actual image is non-negative).

In most real-life problems, this linear description works pretty well. However, at some point, when we start looking for a better accuracy, we must take into consideration non-linear terms. This may …

Location Independent Names For Nomadic Computers, David Steere, Mark Morrissey, Peter Geib, Calton Pu, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Recent advances in the Domain Name System (DNS) and the Dynamic Host Configuration Protocol (DHCP) have enabled a new approach to supporting mobile users: location independent naming. In this approach, machines use the same hostname from any internet location, but use an IP address that corresponds to their current location. We describe a protocol that implements location independent naming for nomadic computers, i.e., machines that do not need transparent mobility. Our protocol allows hosts to move across security domains, uses existing protocols, and preserves existing trust relationships. Therefore, it preserves the performance and security of normal IP for nomadic computers …

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 14, Number 6, June 1998, 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.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 14, Number 5, May 1998, 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.

Adaptation Space: Surviving Non-Maskable Failures, Crispin Cowan, Lois Delcambre, Anne-Francoise Le Meur, Ling Liu, David Maier, Dylan Mcnamee, Michael Miller, Calton Pu, Perry Wagle, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Some failures cannot be masked by redundancies, because an unanticipated situation occurred, because fault-tolerance measures were not adequate, or because there was a security breach (which is not amenable to replication). Applications that wish to continue to offer some service despite nonmaskable failure must adapt to the loss of resources. When numerous combinations of non-maskable failure modes are considered, the set of possible adaptations becomes complex. This paper presents adaptation spaces, a formalism for navigating among combinations of adaptations. An adaptation space describes a collection of possible adaptations of a software component or system, and provides a uniform way of …

Implementation Of A Database System With Boolean Algebra Constraints, András Salamon

School of Computing: Dissertations, Theses, and Student Research

This thesis describes an implementation of a constraint database system with constraints over a Boolean Algebra of sets. The system allows within the input database as well as the queries equality, subset-equality and monotone inequality constraints between Boolean Algebra terms built up using the operators of union, intersection and complement. Hence the new system extends the earlier DISCO system, which only allowed equality and subset-equality constraints between Boolean algebra variables and constants. The new system allows Datalog with Boolean Algebra constraints as the query lan- guage. The implementation includes an extension of Naive and Semi-Naive evaluation methods for Datalog programs …

Rapid Prototyping Using Reprogrammable Logic, Jared L. Bell

Honors Capstone Projects and Theses

No abstract provided.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 14, Number 4, April 1998, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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