Computer Sciences Commons^™

Contributions To The Solution Of Large Nonlinear Systems Via Model-Order Reduction And Interval Constraint Solving Techniques, Leobardo Valera

Open Access Theses & Dissertations

Many engineering problems boil down to solving partial differential equations (PDEs) that describe real-life phenomena. Nevertheless, efficiently and reliably solving such problems constitutes a major challenge in computational sciences and in engineering in general.

PDE-based systems can reach sizes so large after they are discretized. The large size in these problems generate several issues, among them we can mention: large space of storing, computing time, and the most important, lost of accuracy. A popular approach to solving such problems is assume that the PDE's solution is in a subspace, and the solution is sought there. This assumption and later searching …

Japanese Computational Lexicon: A Computational Dictionary Of Japanese Verb Forms, Mayumi Kobayashi

Open Access Theses & Dissertations

This paper presents two main topics: a linguistic analysis of Japanese morphological lexicon focused on verb conjugation and a computational analysis of Japanese verb conjugation in Prolog programming. Prolog is one of the computer programming languages and is used to solve a problem logically with a number of statements called "clauses," which are defining various relationships of the entities. With respect to the linguistic aspect, this paper discusses Japanese verb formation, its conjugation patterns, twelve basic forms of Japanese verbs, and a Japanese morphophonemic process called “音便 (onbin)” by investigating 304 regular verbs and 2 irregular verbs. Among the several …

A Case Study Of Accelerator Performance, Esthela Gallardo

Open Access Theses & Dissertations

In recent years the designs of High Performance Computing (HPC) clusters have become more complex. This is due to the emergence of new processing elements, in particular Graphics Processing Units (GPUs) and other many-core processors that can be combined with multi-core processors to enhance application performance. The design of a cluster includes processing elements that meet the needs of the applications that will run on the system. Unfortunately, it has become increasingly difficult to compare the performance of novel many-core processing elements due to the differences in their architectures. This work describes an attempt to develop a methodology for comparing …

Towards Analytical Techniques For Optimizing Knowledge Acquisition, Processing, Propagation, And Use In Cyberinfrastructure, Leonardo Octavio Lerma

Open Access Theses & Dissertations

For many decades, there has been a continuous progress in science and engineering applications.

A large part of this progress comes from the new knowledge that researchers acquire, propagate, and use. This new knowledge has revolutionized many aspects of our life, from driving to communications to shopping.

Somewhat surprisingly, there is one area of human activity which is the least impacted by the modern technological progress: the very processes of acquiring, processing, and propagating information. When we decide where to place sensors, which algorithm to use for processing the data – we rely mostly on our own intuition and on …

Three Essays On Global Ict Phenomenon: Productivity Paradox, Organizational Ict Use, And Privacy In Social Networks, Faruk Arslan

Open Access Theses & Dissertations

This Dissertation aims to investigate the global diversity in information systems by studying three distinctive phenomena. The first essay investigates the existence of "IT Productivity Paradox" within firms operating in developing countries using an empirical approach. IT Productivity Paradox has been a widely investigated topic within the context of developed countries and primarily studied within the context of developing countries using a single country. Our research addresses a gap in the literature, which is the study of IT Productivity Paradox across several developing countries with diverse characteristics. The second essay studies the contextual factors (firm characteristics and perception of external …

Physical Engagement As A Way To Increase Emotional Rapport In Interactions With Embodied Conversational Agents, Ivan Gris Sepulveda

Open Access Theses & Dissertations

One of the major goals in research on embodied conversational agents (ECAs) is to increase the believability and perceived trustworthiness of agents. To improve the efficacy of the interaction between humans and ECAs, I focus on the development of rapport, which is a complex and extensive behavioral state of affinity, synchronicity, coordination and mutual understanding that is difficult to model, measure and interpret. I present our AGENT Framework and our ECA, Adriana, which is capable of speech recognition and gesture recognition over long periods of time. Our current system provides up to 60 minutes of human-ECA interaction in a jungle-survival …

Multi-Expert Multi-Criteria Decision Making, Joel Henderson

Open Access Theses & Dissertations

Expert analysis and decisions are highly valued assets in a wide variety of fields, from social services to grant funding committees. However, the use of experts can be prohibitive due to either lack of availability or cost. As such, it is desirable to be able to replicate such decisions. However, there are many obstacles that impede an accurate simulation of expert decisions. For example, despite looking at the same information, two experts may disagree on the decisions. In addition, a single expert may make inconsistent decisions across similar scenarios.

In this work, we focus on multi-criteria decision making and in …

Iso-Power-Efficiency: An Approach To Scaling Application Codes With A Power Budget, Rogelio Long

Open Access Theses & Dissertations

For many applications, speedup saturates and parallel efficiency decreases if the problem size is held fixed while increasing the number of processors. For some problems, it is possible to maintain a fixed parallel efficiency by increasing both the problem size and the number of processing elements. The rate at which the problem size must increase to maintain constant efficiency for a given rate of increase of the number of processors is given by the iso-efficiency function. We have developed a new scalability function called iso-power-efficiency that determines the rate at which the problem size must increase to maintain constant efficiency …

Bounded Rationality In Decision Making Under Uncertainty: Towards Optimal Granularity, Joseph Anthony Lorkowski

Open Access Theses & Dissertations

Starting from well-known studies by Kahmenan and Tversky, researchers have found many examples when our decision making seems to be irrational. We show that this seemingly irrational decision making can be explained if we take into account that human abilities to process information are limited. As a result, instead of the exact values of different quantities, we operate with granules that contain these values. On several examples, we show that optimization under such granularity restriction indeed leads to observed human decision making. Thus, granularity helps explain seemingly irrational human decision making.

Similar arguments can be used to explain the success …

Computation Offloading Decisions For Reducing Completion Time, Salvador Melendez

Open Access Theses & Dissertations

Mobile devices are being widely used in many applications such as image processing, computer vision (e.g. face detection and recognition), wearable computing, language translation, and battlefield operations. However, mobile devices are constrained in terms of their battery life, processor performance, storage capacity, and network bandwidth. To overcome these issues, there is an approach called Computation Offloading, also known as cyber-foraging and surrogate computing. Computation offloading consists of migrating computational jobs from a mobile device to more powerful remote computing resources. Upon completion of the job, the results are sent back to the mobile device. However, a decision must be made; …

Fuzzy Intervals As Foundation Of Metrological Support For Computations With Inaccurate Data, Konstantin K. Semenov, Gennady N. Solopchenko, Vladik Kreinovich

Departmental Technical Reports (CS)

In this paper, we discuss the possibility of using the formalism of fuzzy intervals as a basis for computational metrology. We consider advantages of using fuzzy intervals instead of the traditional intervals as a characteristic of uncertainty of the results of computations with inaccurate data.

A Catalog Of While Loop Specification Patterns, Aditi Barua, Yoonsik Cheon

Departmental Technical Reports (CS)

This document provides a catalog of while loop patterns along with their skeletal specifications. The specifications are written in a functional form known as intended functions. The catalog can be used to derive specifications of while loops by first matching the loops to the cataloged patterns and then instantiating the skeletal specifications of the matched patterns. Once their specifications are formulated and written, the correctness of while loops can be proved rigorously or formally using the functional program verification technique in which a program is viewed as a mathematical function from one program state to another.

Construction Of Shear Wave Models By Applying Multi-Objective Optimization To Multiple Geophysical Data Sets, Lennox Thompson, Aaron A. Velasco, Vladik Kreinovich

Departmental Technical Reports (CS)

For this work, our main purpose is to obtain a better understanding of the Earth's tectonic processes in the Texas region, which requires us to analyze the Earth structure. We expand on a constrained optimization approach for a joint inversion least-squares (LSQ) algorithm to characterize a one-dimensional Earth's structure of Texas with the use of multiple geophysical data sets. We employed a joint inversion scheme using multiple geophysical datasets for the sole purpose of obtaining a three-dimensional velocity structure of Texas in order to identify an ancient rift system within Texas. In particular, we use data from the USArray, which …

What If We Only Have Approximate Stochastic Dominance?, Vladik Kreinovich, Hung T. Nguyen, Songsak Sriboonchitta

Departmental Technical Reports (CS)

In many practical situations, we need to select one of the two alternatives, and we do not know the exact form of the user's utility function -- e.g., we only know that it is increasing. In this case, stochastic dominance result says that if the cumulative distribution function (cdf) corresponding to the first alternative is always smaller than or equal than the cdf corresponding to the second alternative, then the first alternative is better. This criterion works well in many practical situations, but often, we have situations when for most points, the first cdf is smaller but at some points, …

How To Assign Weights To Different Factors In Vulnerability Analysis: Towards A Justification Of A Heuristic Technique, Beverly Rivera, Irbis Gallegos, Vladik Kreinovich

Departmental Technical Reports (CS)

The main objective of vulnerability analysis is to select the alternative which is the least vulnerable. To make this selection, we must describe the vulnerability of each alternative by a single number -- then we will select the alternative with the smallest value of this vulnerability index. Usually, there are many aspects of vulnerability: vulnerability of a certain asset to a storm, to a terrorist attack, to hackers' attack, etc. For each aspect, we can usually gauge the corresponding vulnerability, the difficulty is how to combine these partial vulnerabilities into a single weighted value. In our previous research, we proposed …

Dealing With Uncertainties In Computing: From Probabilistic And Interval Uncertainty To Combination Of Different Types Of Uncertainty, Vladik Kreinovich

Departmental Technical Reports (CS)

To predict values of future quantities, we apply algorithms to the current and past measurement results. Because of the measurement errors and model inaccuracy, the resulting estimates are, in general, different from the desired values of the corresponding quantities. There exist methods for estimating this difference, but these methods have been mainly developed for the two extreme cases: the case when we know the exact probability distributions of all the measurement errors and the interval case, when we only know the bounds on the measurement errors. In practice, we often have some partial information about the probability distributions which goes …

R-Bounded Fuzzy Measures Are Equivalent To Epsilon-Possibility Measures, Karen A. Richart-Ruiz, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

Traditional probabilistic description of uncertainty is based on additive probability measures. To describe non-probabilistic uncertainty, it is therefore reasonable to consider non-additive measures. An important class of non-additive measures are possibility measures, for which m(A union B) = max(m(A), m(B)). In this paper, we show that possibility measures are, in some sense, universal approximators: for every epsilon > 0, every non-additive measure which satisfies a certain reasonable boundedness property is equivalent to a measure which is epsilon-close to a possibility measure.

How To Estimate Relative Spatial Resolution Of Different Maps Or Images Of The Same Area?, Christian Servin, A A. Velasco, Vladik Kreinovich

Departmental Technical Reports (CS)

In this paper, we describe how to estimate relative spatial resolution of different maps or images of the same area under uncertainty. We consider probabilistic and fuzzy approaches and we show that both approaches lead to the same estimates -- which makes us more confident that this joint result is reasonable.

A Simple Probabilistic Explanation Of Term Frequency-Inverse Document Frequency (Tf-Idf) Heuristic (And Variations Motivated By This Explanation), Lukas Havrlant, Vladik Kreinovich

Departmental Technical Reports (CS)

In document analysis, an important task is to automatically find keywords which best describe the subject of the document. One of the most widely used techniques for keyword detection is a technique based on the term frequency-inverse document frequency (tf-idf) heuristic. This techniques has some explanations, but these explanations are somewhat too complex to be fully convincing. In this paper, we provide a simple probabilistic explanation for the tf-idf heuristic. We also show that the ideas behind explanation can help us come up with more complex formulas which will hopefully lead to a more adequate detection of keywords.

Wiener's Conjecture About Transformation Groups Helps Predict Which Fuzzy Techniques Work Better, Francisco Zapata, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

Often, application success only comes when we select specific fuzzy techniques (t-norm, membership function, etc.) -- and in different applications, different techniques are the best. How to find the best technique? Exhaustive search of all techniques is not an option: there are too many of them. We need to come up with a narrow class of promising techniques, so that trying them all is realistic. In this paper, we show that such a narrowing can be obtained from transformation groups techniques motivated by N. Wiener's conjecture -- which was, in its turn, motivated by observations about human vision.

Towards Efficient Algorithms For Approximating A Fuzzy Relation By Fuzzy Rules: Case When "And"- And "Or"-Operation Are Distributive, Christian Servin, Vladik Kreinovich

Departmental Technical Reports (CS)

A generic fuzzy relation often requires too many parameters to represent -- especially when we have a relation between many different quantities x1, ..., xn. There is, however, a class of relations which require much fewer parameters to describe - namely, relations which come from fuzzy rules. It is therefore reasonable to approximate a given relation by fuzzy rules. In this paper, we explain how this can be done in an important case when "and"- and "or"-operation are distributive -- and we also explain why this case is important.

Interval And Symmetry Approaches To Uncertainty -- Pioneered By Wiener -- Helps Explain Many Seemingly Irrational Human Behaviors: A Case Study, Joe Lorkowski, Vladik Kreinovich

Departmental Technical Reports (CS)

It has been observed that in many cases, when we present a user with three selections od different price (and, correspondingly, different quality), then the user selects the middle selection. This empirical fact -- known as a compromise effect -- seems to contradicts common sense. Indeed, when a rational decision-maker selects one of the two alternatives, and then we add an additional option, then the user will either keep the previous selection or switch to a new option, but he/she will not select a previously rejected option. However, this is exactly what happens under the compromise effect. If we present …

Writing Self-Testing Java Classes With Selftest, Yoonsik Cheon

Departmental Technical Reports (CS)

This document provides a tutorial introduction to Java annotations called SelfTest. The SelfTest annotations allow one to annotate Java classes with test data, and the SelfTest annotation processor generates executable JUnit test classes from annotated Java classes by translating test cases to executable JUnit tests. The SelfTest annotations not only automate unit testing of Java classes significantly but also provides a step toward writing self-testing Java classes by embedding test data in source code for both compile and runtime processing.

Simpler-To-Describe Cases Are Often More Difficult To Prove: A Possible Explanation, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

In many areas of mathematics, simpler-to-describe cases are often more difficult to prove. In this paper, we provide examples of such phenomena (Bieberbach's Conjecture, Poincar\'e Conjecture, Fermat's Last Theorem), and we provide a possible explanation for this empirical fact.

Logic Of Scientific Discovery: How Physical Induction Affects What Is Computable, Vladik Kreinovich, Olga Kosheleva

Departmental Technical Reports (CS)

Most of our knowledge about a physical world comes from physical induction: if a hypothesis is confirmed by a sufficient number of observations, we conclude that this hypothesis is universally true. We show that a natural formalization of this property affects what is computable when processing measurement and observation results, and we explain how this formalization is related to Kolmogorov complexity and randomness. We also consider computational consequences of an alternative idea also coming form physics: that no physical law is absolutely true, that every physical law will sooner or later need to be corrected. It turns out that this …

Roadmap For Graduating Students With Expertise In The Analysis And Development Of Secure Cyber-Systems, Ann Q. Gates, Salamah Salamah, Luc Longpre

Departmental Technical Reports (CS)

Modern society is intensely and irreversibly dependent on software systems of extraordinary size and complexity. This includes software systems in domain areas such as defense, energy, communication, transportation, and manufacturing. Due to the rapid expansion and reliance on the global Internet for day-to-day functions of individuals, organizations, governments, and industry around the world, cyber-security has emerged as an essential component of computing curricula. To address regional and national needs, the Computer Science Department has defined a roadmap for educating and preparing students who have expertise in the analysis and development of secure cyber-systems. Toward that vision, the department has set …

Fuzzy Logic Ideas Can Help In Explaining Kahneman And Tversky's Empirical Decision Weights, Joe Lorkowski, Vladik Kreinovich

Departmental Technical Reports (CS)

Analyzing how people actually make decisions, the Nobelist Daniel Kahneman and his co-author Amos Tversky found out that instead of maximizing the expected gain, people maximize a weighted gain, with weights determined by the corresponding probabilities. The corresponding empirical weights can be explained qualitatively, but quantitatively, these weights remains largely unexplained. In this paper, we show that with a surprisingly high accuracy, these weights can be explained by fuzzy logic ideas.

From Interval-Valued Probabilities To Interval-Valued Possibilities: Case Studies Of Interval Computation Under Constraints, Luis C. Gutierrez, Martine Ceberio, Vladik Kreinovich, Rebekah L. Gruver, Mariana Peña, Mathew J. Rister, Abraham Saldaña, John Vasquez, Janelle Ybarra, Salem Benferhat

Departmental Technical Reports (CS)

In many engineering situations, we need to make decisions under uncertainty. In some cases, we know the probabilities p_i of different situations i; these probabilities should add up to 1. In other cases, we only have expert estimates of the degree of possibility μ_ii of different situations; in accordance with the possibility theories, the largest of these degrees should be equal to 1.

In practice, we often only know these degrees p_i and μ_ii with uncertainty. Usually, we know the upper bound and the lower bound on each of these values. In other words, …

Decision Making Under Interval Uncertainty: What Can And What Cannot Be Computed In Linear Time And In Real Time, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

In engineering, we constantly need to make decisions: which design to select, which parameters to select for this design, etc.

The traditional approach to decision making is based on the assumption that we know all possible consequences of each alternative, and we know the probability of each such consequence. Under this assumption, we can describe a rational decision-making process: to each possible consequence, we assign a numerical values called its utility, and we select the alternative for which the expected value of the utility is the largest.

An important advantage of this approach is that it can be performed in …

Extending Ocl To Better Express Uml Qualified Associations, Alla Dove, Aditi Barua, Yoonsik Cheon

Departmental Technical Reports (CS)

A qualified association in the Unified Modeling Language (UML) is an association that allows one to restrict the objects referred in an association using a key called a qualifier. A qualified association can appear in a constraint written in the Object Constraint Language (OCL) to specify a precise UML model. However, the OCL notation fails to provide appropriate support for expressing certain types of constraints written using qualified associations. In this paper we first describe a deficiency of OCL in expressing qualified associations and then propose a small extension to OCL to make it more expressive. The key idea of …