Computer Engineering Commons^™

Which Algorithms Are Feasible? Maxent Approach, Daniel E. Cooke, Vladik Kreinovich, Luc Longpre

Departmental Technical Reports (CS)

It is well known that not all algorithms are feasible; whether an algorithm is feasible or not depends on how many computational steps this algorithm requires. The problem with the existing definitions of feasibility is that they are rather ad hoc. Our goal is to use the maximum entropy (MaxEnt) approach and get more motivated definitions.

If an algorithm is feasible, then, intuitively, we would expect the following to be true:

If we have a flow of problems with finite average length L, then we expect the average time T to be finite as well.

Thus, we can say …

Maximum Entropy Approach To Optimal Sensor Placement For Aerospace Non-Destructive Testing, Roberto A. Osegueda, Carlos M. Ferregut, Mary J. George, Jose M. Gutierrez, Vladik Kreinovich

Departmental Technical Reports (CS)

The ideal design of an airplane should include built-in sensors that are pre-blended in the perfect aerodynamic shape. Each built-in sensor is expensive to blend in and requires continuous maintenance and data processing, so we would like to use as few sensors as possible. The ideal formulation of the corresponding optimization problem is, e.g., to minimize the average detection error for fault locations. However, there are two obstacles to this ideal formulation:

--First, this ideal formulation requires that we know the probabilities of different fault locations and the probabilities of different aircraft exploitation regimes. In reality, especially for a …

Soft Computing Explains Heuristic Numerical Methods In Data Processing And In Logic Programming, Hung T. Nguyen, Vladik Kreinovich, Bernadette Bouchon-Meuiner

Departmental Technical Reports (CS)

We show that fuzzy logic and other soft computing approaches explain and justify heuristic numerical methods used in data processing and in logic programming, in particular, M-methods in robust statistics, regularization techniques, metric fixed point theorems, etc.

Non-Equilibrium Thermodynamics Explains Semiotic Shapes: Applications To Astronomy And To Non-Destructive Testing Of Aerospace Systems, Roberto A. Osegueda, Carlos M. Ferregut, Mary J. George, Jose M. Gutierrez, Vladik Kreinovich

Departmental Technical Reports (CS)

Proceedings of the International Conference on Intelligent Systems and Semiotics (ISAS'97), National Institute of Standards and Technology Publ., Gaithersburg, MD, 1997, pp. 378-382.

Celestial bodies such as galaxies, stellar clusters, planetary systems, etc., have different geometric shapes (e.g., galaxies can be spiral or circular, etc.). Usually, complicated physical theories are used to explain these shapes; for example, several dozen different theories explain why many galaxies are of spiral shape. Some rare shapes are still difficult to explain.

It turns out that to explain these "astroshapes", we do not need to know the details of physical equations: practically all the shapes …

Multi-Resolution Data Processing: It Is Necessary, It Is Possible, It Is Fundamental, Scott A. Starks, Vladik Kreinovich, Alex Meystel

Departmental Technical Reports (CS)

Experience shows that many data processing problems are difficult to solve, and some of these problems have even been proven to be computationally intractable. Human experts successfully solve many such problems by using a hierarchical, multi-resolution approach. These multi-resolution methods are, in several cases, provably optimal. However, due to the computational intractability of the problem itself, the multi-resolution approach can only work if the systems that we are analyzing are themselves hierarchical. We show that, first, due to (inevitable) measurement inaccuracies, an arbitrary input data is consistent with the hierarchical model, and second, that in many cases, the actual physical …

Towards Computers Of Generation Omega - Non-Equilibrium Thermodynamics, Granularity, And Acausal Processes: A Brief Survey, Misha Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

Proceedings of the International Conference on Intelligent Systems and Semiotics (ISAS'97), National Institute of Standards and Technology Publ., Gaithersburg, MD, 1997, pp. 383-388.

Nowadays, we are using mainly computer of fourth generation, and we are designing fifth-generation computers. It is reasonable to ask: what is the perspective? What will the computers of generation omega look like?

--As the speed of data processing increases, we face a natural limitation of causality, according to which the speed of all processes is limited by the speed of light.

--Lately, a new area of acausal (causality violating) processes has entered mainstream physics.

This …

How To Make World Wide Web Sites Faster And Easier To Use, Misha Kosheleva

Departmental Technical Reports (CS)

Working Notes of the AAAI Symposium on Frontiers in Soft Computing and Decision Systems, Boston, MA, November 8-10, 1997.

We propose a new idea of organizing Web sites so that the Web will be easier and faster to use.

Soft Computing: Frontiers? A Case Study Of Hyper-Spectral Satellite Imaging, Scott A. Starks, Vladik Kreinovich

Departmental Technical Reports (CS)

Soft computing methods such as fuzzy control, neural networks, etc., often require lots of computations even for small amounts of data. It is, therefore, sometimes believed that for larger amounts of data, the required amount of computations will be so large that we will reach the frontiers of soft computing.

In this paper, we show, on the example of hyper-spectral satellite imaging, that this belief is often too pessimistic. We should not be afraid to use (or at least to try to use) soft computing methods even for large amounts of data.

Multi-Criteria Optimization - An Important Foundation Of Fuzzy System Design, Hung T. Nguyen, Vladik Kreinovich

Departmental Technical Reports (CS)

In many real-life design situations, there are several different criteria that we want to optimize, and these criteria are often in conflict with each other. Traditionally, such multi-criteria optimization situations are handled in an ad hoc manner, when different conflicting criteria are artificially combined into a single combination objective that is then optimized. The use of unnatural ad hoc tools is clearly not the best way of describing a very natural aspect of human reasoning. Fuzzy logic describes a much more natural way of handling multi-criterion optimization problems: when we cannot maximize each of the original conflicting criteria 100%, we …

Computers Of Generation Omega, Vladik Kreinovich

Departmental Technical Reports (CS)

To make computers faster, we must take smaller and smaller processing elements, and to analyze these elements, we need to take into consideration more and more subtle quantum effects. A. Stern has shown a natural way to use quantum field theory for computing. It turns out that if we take into consideration all quantum effects, then this idea leads to an even faster performance.