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Full-Text Articles in Engineering

We Live In The Best Of Possible Worlds: A Proof, Guoqing Liu, Vladik Kreinovich Apr 1999

We Live In The Best Of Possible Worlds: A Proof, Guoqing Liu, Vladik Kreinovich

Departmental Technical Reports (CS)

It is well known that equations of motions and equations which describe the dynamics of physical fields can be deduced from the condition the action S (determined by the corresponding Lagrange function) is optimal. In other words, there is an optimality criterion on the set of all trajectories, and the actual trajectory is optimal with respect to this criterion.

The next reasonable question is: where does this optimality criterion on the set of all trajectories (i.e., the corresponding Lagrange function) come from? It is reasonable to assume that (similarly) on the set of all Lagrange functions, there is an optimality …


1999 (Spring) Ensi Informer Magazine, Morehead State University. Engineering Sciences Department Apr 1999

1999 (Spring) Ensi Informer Magazine, Morehead State University. Engineering Sciences Department

ENSI Informer Magazine Archive

The ENSI Informer Magazine published in the spring of 1999.


Information Modeling And Method Engineering: A Psychological Perspective, Keng Siau Apr 1999

Information Modeling And Method Engineering: A Psychological Perspective, Keng Siau

Research Collection School Of Computing and Information Systems

Information modeling is the cornerstone of information systems analysis and design. Information models, the products of information modeling, not only provide the abstractions required to facilitate communication between the analysts and end users, but they also provide a formal basis for developing tools and techniques used in information systems development. The process of designing, constructing, and adapting information modeling methods for information systems development is known as method engineering. Despite the pivotal role of modeling methods in successful information systems development, most modeling methods are designed based on common sense and intuition of the method designers with little or no …


Locating The Whole Pattern Is Better Than Locating Its Pieces: A Geometric Explanation Of An Empirical Phenomenon, Scott A. Starks, Vladik Kreinovich Mar 1999

Locating The Whole Pattern Is Better Than Locating Its Pieces: A Geometric Explanation Of An Empirical Phenomenon, Scott A. Starks, Vladik Kreinovich

Departmental Technical Reports (CS)

In many practical problems, we must find a pattern in an image. For situations in which the desired pattern consists of several simple components, the traditional approach is first to look for such components, and then to see whether the relative locations of these components are consistent with the pattern. Recent experiments have shown that a much more efficient pattern recognition can be achieved if we look for the whole pattern (without decomposing it first). In this paper, we give a simple geometric explanation of this empirical fact.


Arithmetic Of Complex Sets: Nickel's Classical Paper Revisited From A Geometric Viewpoint, Vladik Kreinovich, Juergen Wolff Von Gudenberg Mar 1999

Arithmetic Of Complex Sets: Nickel's Classical Paper Revisited From A Geometric Viewpoint, Vladik Kreinovich, Juergen Wolff Von Gudenberg

Departmental Technical Reports (CS)

Due to measurement uncertainty, after measuring a value of a physical quantity (or quantities), we do not get its exact value, we only get a set of possible values of this quantity (quantities). In case of 1-D quantities, we get an interval of possible values. It is known that the family of all real intervals is closed under point-wise arithmetic operations (+,-,*) (i.e., this family forms an arithmetic). This closeness is efficiently used to estimate the set of possible values for y=f(x1,...,xn) from the known sets of possible values for xi.

In some practical problems, physical quantities are complex-valued; it …


Chu Spaces: Towards New Foundations For Fuzzy Logic And Fuzzy Control, With Applications To Information Flow On The World Wide Web, Hung T. Nguyen, Vladik Kreinovich, Guoqing Liu Mar 1999

Chu Spaces: Towards New Foundations For Fuzzy Logic And Fuzzy Control, With Applications To Information Flow On The World Wide Web, Hung T. Nguyen, Vladik Kreinovich, Guoqing Liu

Departmental Technical Reports (CS)

We show that Chu spaces, a new formalism used to describe parallelism and information flow, provide uniform explanations for different choices of fuzzy methodology, such as choices of fuzzy logical operations, of membership functions, of defuzzification, etc.


Towards Faster, Smoother, And More Compact Fuzzy Approximation, With An Application To Non-Destructive Evaluation Of Space Shuttle's Structural Integrity, Yeung Yam, Roberto Osegueda, Vladik Kreinovich Mar 1999

Towards Faster, Smoother, And More Compact Fuzzy Approximation, With An Application To Non-Destructive Evaluation Of Space Shuttle's Structural Integrity, Yeung Yam, Roberto Osegueda, Vladik Kreinovich

Departmental Technical Reports (CS)

It is known that fuzzy systems are universal approximators, i.e., any input-output system can be approximated, within any given accuracy, by a system described by fuzzy rules. Fuzzy rules work well in many practical applications. However, in some applications, the existing fuzzy rule approximation techniques are not sufficient:

First, in many practical problems (e.g., in many control applications), derivatives of the approximated function are very important, and so, we want not only the approximating function to be close to the approximated one, but we also want their derivatives to be close; however, standard fuzzy approximation techniques do not guarantee the …


A New Look At Fuzzy Theory Via Chu Spaces, Hung T. Nguyen, Berlin Wu, Vladik Kreinovich Mar 1999

A New Look At Fuzzy Theory Via Chu Spaces, Hung T. Nguyen, Berlin Wu, Vladik Kreinovich

Departmental Technical Reports (CS)

We propose to use Chu categories as a general framework for uncertainty analysis, with a special attention to fuzzy theory. We emphasize the fact that by viewing fuzzy concepts as Chu spaces, we can discover new aggregation operators, and model interactions and relationship between fuzzy data; these possibilities are due, in essence, to the category structure of Chu spaces, and especially to their morphisms. This paper is a tutorial introduction to the subject.


An Optimality Criterion For Arithmetic Of Complex Sets, Vladik Kreinovich, Juergen Wolff Von Gudenberg Mar 1999

An Optimality Criterion For Arithmetic Of Complex Sets, Vladik Kreinovich, Juergen Wolff Von Gudenberg

Departmental Technical Reports (CS)

Uncertainty of measuring complex-valued physical quantities can be described by complex sets. These sets can have complicated shapes, so we would like to find a good approximating family of sets. Which approximating family is the best? We reduce the corresponding optimization problem to a geometric one: namely, we prove that, under some reasonable conditions, an optimal family must be shift-, rotation- and scale-invariant. We then use this geometric reduction to conclude that the best approximating low-dimensional families consist of sets with linear or circular boundaries. This result is consistent with the fact that such sets have indeed been successful in …


On Average Bit Complexity Of Interval Arithmetic, Chadi Hamzo, Vladik Kreinovich Mar 1999

On Average Bit Complexity Of Interval Arithmetic, Chadi Hamzo, Vladik Kreinovich

Departmental Technical Reports (CS)

In many practical situations, we know only the intervals which contain the actual (unknown) values of physical quantities. If we know the intervals [x] for a quantity x and [y] for another quantity y, then, for every arithmetic operation *, the set of possible values of x*y also forms an interval; the operations leading from [x] and [y] to this new interval are called interval arithmetic operations. For addition and subtraction, corresponding interval operations consist of two corresponding operations with real numbers, so there is no hope of making them faster. The best known algorithms for interval multiplication consists of …


Towards Intelligent Virtual Environment For Training Medical Doctors In Surgical Pain Relief, Richard Alo, Kenneth Alo, Vladik Kreinovich Mar 1999

Towards Intelligent Virtual Environment For Training Medical Doctors In Surgical Pain Relief, Richard Alo, Kenneth Alo, Vladik Kreinovich

Departmental Technical Reports (CS)

Chronic pain is a serious health problem affecting millions of people worldwide. Spinal cord stimulation is one of the most effective methods of easing the chronic pain. For most patients, a careful selection of weak electric currents drastically decreases the pain level. Engineering progress leads to more and more flexible devices that offer a wide variety of millions of possible simulation regimes. It is not possible to test all of them on each patient, we need an intelligent method of choosing an appropriate simulation regime. In this paper, we describe the need for an intelligent virtual environment for training medical …


System Reliability: A Case When Fuzzy Logic Enhances Probability Theory's Ability To Deal With Real-World Problems, Timothy J. Ross, Carlos M. Ferregut, Roberto Osegueda, Vladik Kreinovich Mar 1999

System Reliability: A Case When Fuzzy Logic Enhances Probability Theory's Ability To Deal With Real-World Problems, Timothy J. Ross, Carlos M. Ferregut, Roberto Osegueda, Vladik Kreinovich

Departmental Technical Reports (CS)

In his recent paper "Probability theory needs an infusion of fuzzy logic to enhance its ability to deal with real-world problems", L. Zadeh explains that probability theory needs an infusion of fuzzy logic to enhance its ability to deal with real-world problems. In this talk, we give an example of a real-world problem for which such an infusion is indeed successful: the problem of system reliability.


From Fuzzy Models To Fuzzy Control, Chitta Baral, Vladik Kreinovich, Hung T. Nguyen, Yeung Yam Mar 1999

From Fuzzy Models To Fuzzy Control, Chitta Baral, Vladik Kreinovich, Hung T. Nguyen, Yeung Yam

Departmental Technical Reports (CS)

Traditional (non-fuzzy) control methodology deals with situations when we know exactly how the system behaves and how it will react to different controls, and we want to choose an appropriate control strategy. This methodology enables us to transform the description of the plant's (system's) behavior into an appropriate control strategy. In many practical situations, we do not have the exact knowledge of the system's behavior, but we have expert-supplied fuzzy rules which describe this behavior. In such situations, it is desirable to transform these description rules into rules describing control. There exist several reasonable heuristics for such transformation; however, the …


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 15, Number 3, March 1999, College Of Engineering And Computer Science, Wright State University Mar 1999

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 15, Number 3, March 1999, 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.


Performance Analysis Of Tcp Enhancements In Satellite Data Networks, Ren H. Broyles Mar 1999

Performance Analysis Of Tcp Enhancements In Satellite Data Networks, Ren H. Broyles

Theses and Dissertations

This research examines two proposed enhancements to the well-known Transport Control Protocol (TCP) in the presence of noisy communication links. The Multiple Pipes protocol is an application-level adaptation of the standard TCP protocol, where several TCP links cooperate to transfer data. The Space Communication Protocol Standard - Transport Protocol (SCPS-TP) modifies TCP to optimize performance in a satellite environment. While SCPS-TP has inherent advantages that allow it to deliver data more rapidly than Multiple Pipes, the protocol, when optimized for operation in a high-error environment, is not compatible with legacy TCP systems, and requires changes to the TCP specification. This …


An Improved Asynchronous Implementation Of A Fast Fourier Transform Architecture For Space Applications, David J. Barnhart Mar 1999

An Improved Asynchronous Implementation Of A Fast Fourier Transform Architecture For Space Applications, David J. Barnhart

Theses and Dissertations

A second-generation fully asynchronous Fast Fourier Transform (FFT) processor for space applications is developed in this thesis. A high-performance patented FFT architecture invented by Suter and Stevens was used as the basis for a 16-point FFT (FFT-16) processor design. A brief derivation of the architecture, the asynchronous design methodologies used and space-based integrated circuit issues are presented. The Synopsys VLSI CAD system and a radiation tolerant design library developed by the Air Force Research Laboratory were used to implement the design. A critical building block of the FFT-16, the FFT-4, was fabricated as a cost-effective method to validate the cell …


Asymmetric Load Balancing On A Heterogeneous Cluster Of Pcs, Christopher A. Bohn Mar 1999

Asymmetric Load Balancing On A Heterogeneous Cluster Of Pcs, Christopher A. Bohn

Theses and Dissertations

In recent years, high performance computing with commodity clusters of personal computers has become an active area of research. Many organizations build them because they need the computational speedup provided by parallel processing but cannot afford to purchase a supercomputer. With commercial supercomputers and homogenous clusters of PCs, applications that can be statically load balanced are done so by assigning equal tasks to each processor. With heterogeneous clusters, the system designers have the option of quickly adding newer hardware that is more powerful than the existing hardware. When this is done, the assignment of equal tasks to each processor results …


Te Scattering From Bubbles In Ram, John G. Cochran Mar 1999

Te Scattering From Bubbles In Ram, John G. Cochran

Theses and Dissertations

This research looks at various bubble sizes in one particular magnetic RAM (MAURAM) type, from grazing incidence (00) to 450 and at a frequency range from 2-18 GHz, TE polarization. The results from the absolute RCS measurement of the various sized RAM bubbles are discussed in terms of a frequency dependent increase in RCS. In the frequency band of interest, 2-18GHz, a RAM bubble increases the RCS at all angles, from grazing incidence (00) to 450. From 10-18GHz the RAM bubble does not cause an increase in RCS. In general the highest RCS is at 2GHz and tapers down as …


Constructive Induction Machines For Data Mining, Marek Perkowski, Stanislaw Grygiel, Qihong Chen, Dave Mattson Mar 1999

Constructive Induction Machines For Data Mining, Marek Perkowski, Stanislaw Grygiel, Qihong Chen, Dave Mattson

Electrical and Computer Engineering Faculty Publications and Presentations

"Learning Hardware" approach involves creating a computational network based on feedback from the environment (for instance, positive and negative examples from the trainer), and realizing this network in an array of Field Programmable Gate Arrays (FPGAs). Computational networks can be built based on incremental supervised learning (Neural Net training) or global construction (Decision Tree design). Here we advocate the approach to Learning Hardware based on Constructive Induction methods of Machine Learning (ML) using multivalued functions. This is contrasted with the Evolvable Hardware (EHW) approach in which learning/evolution is based on the genetic algorithm only.


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 15, Number 2, February 1999, College Of Engineering And Computer Science, Wright State University Feb 1999

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 15, Number 2, February 1999, 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.


Design, Implementation, And Evaluation Of A Shared-Memory Parellel Processing System (Smpps), Eric H. Staub Jan 1999

Design, Implementation, And Evaluation Of A Shared-Memory Parellel Processing System (Smpps), Eric H. Staub

Theses

As technology reaches its limits of improvements in microprocessor processing speeds, scientists and engineers have to find viable solutions to meet ever-increasing demands for faster processing speed. One such solution is parallel processing. No longer does one have to wait on sequential operations. A specific task can be split in sub-tasks that can run simultaneously, thus reducing the overall execution time of the task.

The design and implementation of these systems is crucial to the effectiveness of parallel systems. A dual-processor SMPPS was designed and implemented in order to demonstrate how multiple processors are a viable solution to increasing the …


A Scalable Multiprocessor, Charles Yarbrough Jan 1999

A Scalable Multiprocessor, Charles Yarbrough

Honors Capstone Projects and Theses

No abstract provided.


Intervals Is All We Need: An Argument, Masao Mukaidono, Yeung Yam, Vladik Kreinovich Jan 1999

Intervals Is All We Need: An Argument, Masao Mukaidono, Yeung Yam, Vladik Kreinovich

Departmental Technical Reports (CS)

In many practical applications of fuzzy methodology, it is desirable to go beyond the interval [0,1] and to consider more general fuzzy values: e.g., intervals, or more general sets of values. In this paper, we show that under some reasonable assumptions, there is no need to go beyond intervals.


Why Clustering In Function Approximation? Theoretical Explanation, Vladik Kreinovich, Yeung Yam Jan 1999

Why Clustering In Function Approximation? Theoretical Explanation, Vladik Kreinovich, Yeung Yam

Departmental Technical Reports (CS)

Function approximation is a very important practical problem: in many practical applications, we know the exact form of the functional dependence y=f(x1,...,xn) between physical quantities, but this exact dependence is complicated, so we need a lot of computer space to store it, and a lot of time to process it, i.e., to predict y from the given xi. It is therefore necessary to find a simpler approximate expression g(x1,...,xn) for this same dependence. This problem has been analyzed in numerical mathematics for several centuries, and it is, therefore, one of the most thoroughly analyzed problems of applied mathematics. There are …


Beyond [0,1] To Intervals And Further: Do We Need All New Fuzzy Values?, Yeung Yam, Masao Mukaidono, Vladik Kreinovich Jan 1999

Beyond [0,1] To Intervals And Further: Do We Need All New Fuzzy Values?, Yeung Yam, Masao Mukaidono, Vladik Kreinovich

Departmental Technical Reports (CS)

In many practical applications of fuzzy methodology, it is desirable to go beyond the interval [0,1] and to consider more general fuzzy values: e.g., intervals, or real numbers outside the interval [0,1]. When we increase the set of possible fuzzy values, we thus increase the number of bits necessary to store each degree, and therefore, increase the computation time which is needed to process these degrees. Since in many applications, it is crucial to get the result on time, it is therefore desirable to make the smallest possible increase. In this paper, we describe such smallest possible increases.


Why Fundamental Physical Equations Are Of Second Order?, Takeshi Yamakawa, Vladik Kreinovich Jan 1999

Why Fundamental Physical Equations Are Of Second Order?, Takeshi Yamakawa, Vladik Kreinovich

Departmental Technical Reports (CS)

In this paper, we use a deep mathematical result (namely, a minor modification of Kolmogorov's solution to Hilbert's 13th problem) to explain why fundamental physical equations are of second order. This same result explain why all these fundamental equations naturally lead to non-smooth solutions like singularity.


Derivation Of Equations Of Motion For A Four Link Robotic Leg For A Walking Vehicle, Andrew B. Wright Jan 1999

Derivation Of Equations Of Motion For A Four Link Robotic Leg For A Walking Vehicle, Andrew B. Wright

Journal of the Arkansas Academy of Science

A four degree of freedom leg for a walking robot has been modeled using Newton's method. Unlike robot manipulators, which have a fixed base, a leg model must include inertial forces due to base motion. These forces have been included in the formulation. These equations can be used for design, simulation, and control. The inverse kinematics for this leg are also presented. This allows the joint angles to be computed from a desired foot-hold position.


Ds Cdma Scheme For Watm With Errors And Erasures Decoding, Beata J. Wysocki, Hans-Jürgen Zepernick, Tadeusz Wysocki Jan 1999

Ds Cdma Scheme For Watm With Errors And Erasures Decoding, Beata J. Wysocki, Hans-Jürgen Zepernick, Tadeusz Wysocki

Department of Electrical and Computer Engineering: Faculty Publications (to 2015)

In the paper, we present simulation results for the 13 channel DS CDMA WATM LAN utilising optimized complex spreading signatures based on Walsh functions. The method to obtain those optimized spreading signatures, as well as the full set of the coefficients giving the minimum level of cross-correlation between any pair of the channels is shown. The resultant system BER as well as the distribution of errors within WATM cells is given. The obtained results indicate that with the application of a hybrid ARQ scheme with errors and erasures decoding, the number of WATM cells which would require retransmission is in …


Fuzzy Systems Are Universal Approximators For A Smooth Function And Its Derivatives, Vladik Kreinovich, Hung T. Nguyen, Yeung Yam Jan 1999

Fuzzy Systems Are Universal Approximators For A Smooth Function And Its Derivatives, Vladik Kreinovich, Hung T. Nguyen, Yeung Yam

Departmental Technical Reports (CS)

One of the reasons why fuzzy methodology is successful is that fuzzy systems are universal approximators, i.e., that we can approximate an arbitrary continuous function within any given accuracy by a fuzzy system. In some practical applications (e.g., in control), it is desirable to approximate not only the original function, but also its derivatives (so that, e.g., a fuzzy control approximating a smooth control will also be smooth). In our paper, we show that for any given accuracy, we can approximate an arbitrary smooth function by a fuzzy systems so that not only the function is approximated within this accuracy, …


Time-Bounded Kolmogorov Complexity May Help In Search For Extra Terrestrial Intelligence (Seti), Martin Schmidt Jan 1999

Time-Bounded Kolmogorov Complexity May Help In Search For Extra Terrestrial Intelligence (Seti), Martin Schmidt

Departmental Technical Reports (CS)

One of the main strategies in Search for Extra Terrestrial Intelligence (SETI) is trying to overhear communications between advanced civilizations. However, there is a (seeming) problem with this approach: advanced civilizations, most probably, save communication expenses by maximally compressing their messages, and the notion of a maximally compressed message is naturally formalized as a message x for which Kolmogorov complexity C(x) is close to its length l(x), i.e., as a "random" message. In other words, a maximally compressed message is indistinguishable from the truly random noise, and thus, trying to detect such a message does not seem to be a …