Engineering Commons^™

Minimum Description Length (Mdl) Principle As A Possible Approach To Arc Detection, Jan Beck, David Nemir, Vladik Kreinovich

Departmental Technical Reports (CS)

Detecting arcing faults is an important but difficult-to-solve practical problem. In this paper, we show how the Minimum Description Length (MDL) Principle can help in solving this problem.

Optimal Prices In The Presence Of Discounts: A New Economic Application Of Choquet Integrals, Hung T. Nguyen, Vladik Kreinovich

Departmental Technical Reports (CS)

In many real-life situations, there are ``package deals'', when customers who buy two or more different items get a special discount. For example, when planning a trip, a deal including airfare and hotel costs less than the airfare and hotel on their own; there are often also special deals when we combine airfare with car rental, and deals that cover all three items plus tickets to local tourist attractions, etc.

Usually, there are several such deals with different combinations and different discounts. What if we plan to buy several different copies of each item: e.g., we plan a group tour …

Spatial Resolution For Processing Seismic Data: Type-2 Methods For Finding The Relevant Granular Structure, Vladik Kreinovich, Jaime Nava, Rodrigo Romero, Julio Olaya, Aaron A. Velasco, Kate C. Miller

Departmental Technical Reports (CS)

One of the main methods of determining the Earth structure is the analysis of the seismic data. Based on the seismic data, we produce a 3-D map describing the density at different locations on different depths. Due to incomplete coverage and measurement uncertainty, this map provides only an approximate description of the actual density distribution. For example, based on the seismic data, it is impossible to distinguish between the densities at two nearby points. In other words, what we actually reconstruct is not a function of 3 variables, but rather values determined on the appropriate spatial granules. Because of this …

How To Describe Spatial Resolution: An Approach Similar To The Central Limit Theorem, Omar Ochoa, Martine Ceberio, Vladik Kreinovich

Departmental Technical Reports (CS)

For spatially distributed quantities v(x), there are two main reasons why the measured value is different from the actual value. First, the sensors are imprecise, so the measured value is slightly different from the actual one. Second, sensors have a finite {\it spatial resolution}: they do not simply measure the value at a single point, they are "blurred", i.e., affected by the values of the nearby points as well. It is known that uncertainty can be often described by the Gaussian distribution. This possibility comes from the Central Limit Theorem, according to which the sum of many independent small measurement …

Toward Computing An Optimal Trajectory For An Environment-Oriented Unmanned Aerial Vehicle (Uav) Under Uncertainty, Jerald Brady, Octavio Lerma, Vladik Kreinovich, Craig Tweedie

Departmental Technical Reports (CS)

Over the past decade a few but increasing number of researchers have begun using Unmanned Aerial Vehicles (UAVs) to expand and improve upon existing remote sensing capabilities in the Arctic. Due to the limited flight time, it is important to make sure that the UAV follows an optimal trajectory -- in which it cover all the points from a given area within the smallest possible trajectory length. Under the usual assumptions that we cover a rectangular area and that each on-board sensor covers all the points with a given radius r, we describe the optimal trajectory. A more complex optimal …

Towards A More Adequate Defuzzification Of Interval-Valued Fuzzy Sets, Vladik Kreinovich, Van Nam Huynh, Yoshiteru Nakamori

Departmental Technical Reports (CS)

It is known that interval-valued fuzzy sets [m(x)] provide a more adequate description of expert uncertainty than the more traditional "type-1" (number-valued) fuzzy techniques. Specifically, an interval-valued fuzzy set can be viewed as a class of possible fuzzy sets m(x) from [m(x)]. In this case, as a result of defuzzification, it is natural to return the range [u] of all possible values u(m) that can be obtained by defuzzifying membership functions m(x) from this class. In practice, it is reasonable to restrict ourselves only to fuzzy numbers m(x), i.e., to "unimodal" fuzzy sets. Under this restriction, in general, we get …

How To Define A Confidence Set For Functions: A New Justification Of The Area Method, Vladik Kreinovich, Gang Xiang, Michael Oberguggenberger

Departmental Technical Reports (CS)

Due to uncertainty, in many problems, we only know the probability of different values. In such situations, we need to make decisions based on these probabilities: e.g., we must tell the user which values are possible and which are not. Often -- e.g., for a normal distribution -- the probability density is everywhere positive, so, theoretically, all real values are possible. In practice, it is usually safe to assume that values whose probability is very small are not possible. For a single variable, this idea is described by a confidence interval C, the interval for which the probability to be …

Femprof: Advancing Females To The Professoriate In Computing, Nestor J. Rodriguez, Richard A. Alo, Sarah Hug, Sangeeta Gad, Nayda Santiago, Gladys O. Ducodray

Departmental Technical Reports (CS)

Considering both the percentage of science and engineering PhDs awarded to women in the twenty year period 1974-2004 and the data from the National Science 2006 Survey of Earned Doctorates 1974-2004, the U.S. National Academies noted that women in 2004 have attained equality with men in their representation in the Social Sciences and Life Sciences but are still lagging in Physical and Computing Sciences and Engineering. In the top 50 engineering departments in the U.S., women earn one-fourth of the PhDs granted in Chemical Engineering and 15% in engineering overall (Handelsman et al, 2005). Although women constitute about half of …

How To Relate Fuzzy And Owa Estimates, Tanja Magoc, Vladik Kreinovich

Departmental Technical Reports (CS)

In many practical situations, we have several estimates x1, ..., xn of the same quantity x, i.e., estimates for which x1 ~ x, x2 ~ x, ..., and xn ~ x. It is desirable to combine (fuse) these estimates into a single estimate for x. From the fuzzy viewpoint, a natural way to combine these estimates is: (1) to describe, for each x and for each i, the degree mu(xi - x) to which x is close to xi, (2) to use a t-norm ("and"-operation) to combine these degrees into a degree to which x is consistent with all n …

Efficient Algorithms For Heavy-Tail Analysis Under Interval Uncertainty, Vladik Kreinovich, Monchaya Chiangpradit, Wararit Panichkitkosolkul

Departmental Technical Reports (CS)

Most applications of statistics to science and engineering are based on the assumption that the corresponding random variables are normally distributed, i.e., distributed according to Gaussian law in which the probability density function d(x) exponentially decreases with x: d(x) ~ exp(-k * x^2). Normal distributions indeed frequently occur in practice. However, there are also many practical situations, including situations from mathematical finance, in which we encounter heavy-tailed distributions, i.e., distributions in which d(x) decreases as d(x) ~ x^(-a). To properly take this uncertainty into account when making decisions, it is necessary to estimate the parameters of such distributions based on …

Metrization Theorem For Space-Times: From Urysohn's Problem Towards Physically Useful Constructive Mathematics, Vladik Kreinovich

Departmental Technical Reports (CS)

In the early 1920s, Pavel Urysohn proved his famous lemma (sometimes referred to as "first non-trivial result of point set topology"). Among other applications, this lemma was instrumental in proving that under reasonable conditions, every topological space can be metrized.

A few years before that, in 1919, a complex mathematical theory was experimentally proven to be extremely useful in the description of real world phenomena: namely, during a solar eclipse, General Relativity theory -- that uses pseudo-Riemann spaces to describe space-time -- has been (spectacularly) experimentally confirmed. Motivated by this success, Urysohn started working on an extension of his lemma …

Extending Maximum Entropy Techniques To Entropy Constraints, Gang Xiang, Vladik Kreinovich

Departmental Technical Reports (CS)

In many practical situations, we have only partial information about the probabilities. In some cases, we have {\em crisp} (interval) bounds on the probabilities and/or on the related statistical characteristics. In other situations, we have {\em fuzzy} bounds, i.e., different interval bounds with different degrees of certainty.

In a situation with uncertainty, we do not know the exact value of the desired characteristic. In such situations, it is desirable to find its worst possible value, its best possible value, and its "typical" value -- corresponding to the "most probable" probability distribution. Usually, as such a "typical" distribution, we select the …

Towards A Natural Proof Of Metrization Theorem For Space-Times, Vladik Kreinovich, Olga Kosheleva

Departmental Technical Reports (CS)

In the early 1920s, Pavel Urysohn proved his famous lemma (sometimes referred to as "first non-trivial result of point set topology"). Among other applications, this lemma was instrumental in proving that under reasonable conditions, every topological space can be metrized.

A few years before that, in 1919, a complex mathematical theory was experimentally proven to be extremely useful in the description of real world phenomena: namely, during a solar eclipse, General Relativity theory -- that uses pseudo-Riemann spaces to describe space-time -- has been (spectacularly) experimentally confirmed. Motivated by this success, Urysohn started working on an extension of his lemma …

Selecting The Best Location For A Meteorological Tower: A Case Study Of Multi-Objective Constraint Optimization, Aline James, Craig Tweedie, Tanja Magoc, Vladik Kreinovich, Martine Ceberio

Departmental Technical Reports (CS)

Using the problem of selecting the best location for a meteorological tower as an example, we show that in multi-objective optimization under constraints, the traditional weighted average approach is often inadequate. We also show that natural invariance requirements lead to a more adequate approach -- a generalization of Nash's bargaining solution.

How To Relate Spectral Risk Measures And Utilities, Songsak Sriboonchitta, Hung T. Nguyen, Vladik Kreinovich

Departmental Technical Reports (CS)

Traditional decision theory describes human behavior and human preferences in terms of utility functions. In the last decades, it was shown that in many economic situations, a reasonable description of the actual decisions can be found if we use a different approach -- of spectral risk measures. In each of these approaches, we first need to empirically find the corresponding function: utility function in the traditional approach and the weighting function for spectral risk measures. Since both approaches provide a reasonable description of the same actual behavior (in particular, of the same actual economic behavior), it is desirable to be …

Why Polynomial Formulas In Soft Computing, Decision Making, Etc.?, Olga Kosheleva, Martine Ceberio, Vladik Kreinovich

Departmental Technical Reports (CS)

We show that in many application areas including soft constraints reasonable requirements of scale-invariance lead to polynomial formulas for combining degrees (of certainty, of preference, etc.)

Towards Improved Trapezoidal Approximation To Intersection (Fusion) Of Trapezoidal Fuzzy Numbers: Specific Procedure And General Non-Associativity Theorem, Gang Xiang, Vladik Kreinovich

Departmental Technical Reports (CS)

In some cases, our uncertainty about a quantity can be described by an interval of its possible values. If we have two or more pieces of interval information about the same quantity, then we can conclude that the actual value belongs to the intersection of these intervals.

In general, we may need a fuzzy number to represent our partial knowledge. A fuzzy number can be viewed as a collection of intervals (alpha-cuts) corresponding to different degrees alpha from [0,1]. In practice, we can only store finitely many alpha-cuts. Usually, we only store the lower and upper alpha-cuts (corresponding to alpha …

Access Control Contracts For Java Program Modules, Carlos E. Rubio-Medrano, Yoonsik Cheon

Departmental Technical Reports (CS)

Application-level security has become an issue in recent years; for example, errors, discrepancies and omissions in the specification of access control constraints of security-sensitive software components are recognized as an important source for security vulnerabilities. We propose to formally specify access control assumptions or constraints of a program module and enforce them at run-time. We call such specifications access control contracts. To realize access control contracts, we extended the JML language, a formal interface specification language for Java, and developed a prototype support tool that translates access control contracts to runtime checks. The access control contract reduces the vulnerability that …

A New Eclipse-Based Jml Compiler Built Using Ast Merging, Amritam Sarcar, Yoonsik Cheon

Departmental Technical Reports (CS)

The Java Modeling Language (JML) is a formal interface specification language to document the behavior of Java program modules and has been used in many research and industrial projects. However, its inability to support Java 5 features such as generics is reducing its user base significantly. Besides, the JML compiler is on average 8.5 times slower than the javac Java compiler. In this paper, we present a new JML compiler built on the Eclipse Java compiler to support Java 5 features. We used a technique called AST merging to implement coarse-grained incremental compilation. In our experiments we observed a significant …

Runtime Constraint Checking Approaches For Ocl, A Critical Comparison, Carmen Avila, Amritam Sarcar, Yoonsik Cheon, Cesar Yeep

Departmental Technical Reports (CS)

There are many benefits of checking design constraints at runtime---for example, automatic detection of design drift or corrosion. However, there is no comparative analysis of different approaches although such an analysis could provide a sound basis for determining the appropriateness of one approach over the others. In this paper we conduct a comparative analysis and evaluation of different constraint checking approaches possible for the Object Constraint Language (OCL). We compare several approaches including (1) direct translation to implementation languages, (2) use of executable assertion languages, and (3) use of aspect-oriented programming languages. Our comparison includes both quantitative metrics such as …

Runtime Assertion Checking For Jml On The Eclipse Platform Using Ast Merging, Amritam Sarcar

Departmental Technical Reports (CS)

The Java Modeling Language (JML) is a formal behavioral interface specification language for Java. It is used for detailed design documentation of Java program modules such as classes and interfaces. JML has been used extensively by many researchers across various projects and has a large and varied spectrum of tool support. It extends from runtime assertion checking (RAC) to theorem proving.

Amongst these tools, RAC and ESC/Java has been used as a common tool for many research projects. RAC for JML is a tool that checks at runtime for possible violations of any specifications. However, lately there has been a …

Estimating Information Amount Under Uncertainty: Algorithmic Solvability And Computational Complexity, Vladik Kreinovich, Gang Xiang

Departmental Technical Reports (CS)

Measurement results (and, more generally, estimates) are never absolutely accurate: there is always an uncertainty, the actual value x is, in general, different from the estimate X. Sometimes, we know the probability of different values of the estimation error dx=X-x, sometimes, we only know the interval of possible values of dx, sometimes, we have interval bounds on the cdf of dx. To compare different measuring instruments, it is desirable to know which of them brings more information - i.e., it is desirable to gauge the amount of information. For probabilistic uncertainty, this amount of information is described by Shannon's entropy; …

What About The Children? Benjamin And Arendt: On Education, Work, And The Political, Jules Simon

Selected Works Temporary Series

This article is a rough draft of an article that I contributed to an edited volume of articles dealing with progressive education theory. I reflect on articles that Hannah Arendt and Walter Benjamin wrote that deal with educational reform and innovation, both political in nature.

What About The Children? Benjamin And Arendt: On Education, Work, And The Political, Jules Simon

Departmental Papers (Philosophy)

This article is a rough draft of an article that I contributed to an edited volume of articles dealing with progressive education theory. I reflect on articles that Hannah Arendt and Walter Benjamin wrote that deal with educational reform and innovation, both political in nature.

An Investigation On Pulsing Performance Of Mn Class Bi-Propellant Thrusters, Carlos Francisco Gomez

Open Access Theses & Dissertations

With the advancement of technology and machining methods, considerable attention has been focused in manufacturing micro thrusters for micro spacecraft applications (Yetter et al, 2003). Micro propulsion systems are currently being investigated for Miniature Kill Vehicles (MKV) and Micro Satellite Systems (MSS) with an emphasis in reducing weight and cost but without affecting performance. Reducing the weight seems practical when reducing the size of the propulsion system, but problems are encountered with system design.

In addition, propulsion requirements strongly influence choice in propellant and complexity. A thorough understanding of stabilizing thrust levels and the ability to control the propulsion system …

Observer-Dependent Model For Analyzing Subjective Parameters In Epidemiology, Milad Zarei

Open Access Theses & Dissertations

Although medical technologies for preventing the contagion and spread of infectious diseases have improved steadily throughout the last century, new infectious diseases are still emerging and spreading swiftly. The modeling of infectious disease spread is crucial in addressing the lack of predictive ability in epidemiology. Managing the spread of infectious diseases requires processing quantitative epidemiological data and the ability to capture the dynamics of the infectious disease in order to provide a measure of control.

In this thesis, I have introducing cognitive biases in diseases spread modeling. For the first time, to the author's knowledge, the human subjective experience has …

A Subthreshold Reconfigurable Architecture For Harsh Environments, Ameet Chavan

Open Access Theses & Dissertations

Energy harvesting and functional reconfigurability are necessary features in order to simultaneously achieve longer operating lifetimes and versatility in application for many next generation electronic systems. The presented research incorporates capabilities that not only enable applications to self-power from ambience but also permit change in functionality based on real-time application requirements. Currently, many applications are battery powered with custom hardware, which severely confines the application platform. Moreover, maintenance and upgrades are prohibitively expensive, particularly in the case of remote locations with limited accessibility. For harsh environments like Space or the battlefield, apart from features such as low power and reconfigurability, …

Engineering Design Educational Model: From Skills To Objectives, Jose Gabriel Davila Rangel

Open Access Theses & Dissertations

The objective of this thesis is to develop an engineering design educational pedagogy on how to improve the engineering design learning experience. The design engineering activity is a complex mix of skills and knowledge that has been taught over decades by directly delivering to the students the design methodologies developed by design researchers and by exposing the students to open ended projects that could develop their design skills. Understanding this we can conclude that the three main pedagogical components of a successful educational design experience are: the design skills, the design methods and the design projects. On one hand, the …

A Tool To Improve And Preserve Flexible Pavement At Intersections, Carlos Jesus Solis

Open Access Theses & Dissertations

Rural intersections originally constructed with thin untreated flexible base and hot mix or a two-course surface treatment tend to experience severe pushing, shoving and rutting. These failures cause an extremely rough surface that can cause damage to small vehicles and potentially cause motorists to lose control of their vehicles. These distresses almost always result in complete failure of the existing pavement that must be repaired several times during the life of the roadway by maintenance forces. In most cases, pavements constructed with the same materials and cross-sections adjacent to the intersection perform adequately.

The sources of and solutions for failure …

Acoustic Reflectometry Using Gaussian-Modulated Sinusoidal Waves And The Ware-Aki Algorithm, Ernesto Rodrigo Vazquez Ceron

Open Access Theses & Dissertations

Acoustic reflectometry, a non invasive technique, consists of solving, the inverse problem of estimating the cross sectional area as function of the distance of a cylindrical cavity by impacting an audible acoustic pulse of high amplitude and short duration, and analyzing the reflected wave. The technique has been applied in Biomedical Engineering to estimate both the area of a human upper airway and the patency of endotracheal tubes as a function of distance. Several ways have been tested to improve the quality of an acoustic pulse and different algorithms have been tested to reduce the losses. However, an acoustic pulse …