Computer Sciences Commons^™

How To Understand Connections Based On Big Data: From Cliques To Flexible Granules, Ali Jalal-Kamali, M. Shahriar Hossain, Vladik Kreinovich

Departmental Technical Reports (CS)

One of the main objectives of science and engineering is to predict the future state of the world -- and to come up with actions which will lead to the most favorable outcome. To be able to do that, we need to have a quantitative model describing how the values of the desired quantities change -- and for that, we need to know which factors influence this change. Usually, these factors are selected by using traditional statistical techniques, but with the current drastic increase in the amount of available data -- known as the advent of {\it big data} -- …

Towards Decision Making Under Interval, Set-Valued, Fuzzy, And Z-Number Uncertainty: A Fair Price Approach, Joe Lorkowski, Vladik Kreinovich, Rafik Aliev

Departmental Technical Reports (CS)

In this paper, we explore one of the possible ways to make decisions under uncertainty: namely, we explain how to define a fair price for a participation in such a decision, and then select an alternative for which the corresponding fair price is the largest. This idea is explained on the examples of interval uncertainty, set-valued, fuzzy, and Z-number uncertainty.

Fitts's Law: Towards A Geometric Explanation, Olga Kosheleva, Vladik Kreinovich, Octavio Lerma

Departmental Technical Reports (CS)

In designing human-computer interfaces, designers use an empirical Fitts's Law, according to which the average time T of accessing an icon of size w at a distance d from the center of the screen is proportional to the logarithm of the ratio w/d. There exist explanations for this law, but these explanations have gaps. In this paper, we show that these gaps can be explained if we analyze this problem from the geometric viewpoint. Thus, we get a geometric explanation of the Fitts's Law.

How To Compare Different Range Estimations: A Symmetry-Based Approach, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

How to compare different range estimators for multivariate functions under uncertainty? To answer this question, we analyze which utility functions can be used for this task. Specifically, we: (1) introduce various invariance assumptions, (2) describe the class of all utility functions which satisfy these assumptions, and (3) show how the resulting utility functions can be used to compare different range estimators.

Range Estimation Under Constraints Is Computable Unless There Is A Discontinuity, Martine Ceberio, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

One of the main problems of interval computations is computing the range of a given function over given intervals. It is known that there is a general algorithm for computing the range of computable functions over computable intervals. However, if we take into account that often in practice, not all possible combinations of the inputs are possible (i.e., that there are constraints), then it becomes impossible to have an algorithm which would always compute this range. In this paper, we explain that the main reason why range estimation under constraints is not always computable is that constraints may introduce discontinuity …

Interleaving Enhances Learning: A Possible Geometric Explanation, Octavio Lerma, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

In the traditional approach to learning, if we want students to learn how to solve different types of problems, we first teach them how to solve problems of the first type, then how to solve problems of the second type, etc. It turns out that we can speed up learning if we interleave problems of different types. In particular, it has bene empirically shown that interleaving problems of four different types leads to a double speed-up. In this paper, we provide a possible geometric explanation for this empirical fact.

From Global To Local Constraints: A Constructive Version Of Bloch's Principle, Martine Ceberio, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

Generalizing several results from complex analysis, A. Bloch formulated an informal principle -- that for every global implication there is a stronger local implication. This principle has been formalized for complex analysis, but is has been successfully used in other areas as well. In this paper, we propose a new formalization of Bloch's Principle, and we show that in general, the corresponding localized version can be obtained algorithmically.

How To Fully Represent Expert Information About Imprecise Properties In A Computer System -- Random Sets, Fuzzy Sets, And Beyond: An Overview, Hung T. Nguyen, Vladik Kreinovich

Departmental Technical Reports (CS)

To help computers make better decisions, it is desirable to describe all our knowledge in computer-understandable terms. This is easy for knowledge described in terms on numerical values: we simply store the corresponding numbers in the computer. This is also easy for knowledge about precise (well-defined) properties which are either true or false for each object: we simply store the corresponding "true" and "false" values in the computer. The challenge is how to store information about imprecise properties. In this paper, we overview different ways to fully store the expert information about imprecise properties. We show that in the simplest …

A Feasible Algorithm For Checking N-Scissors Congruence Of Polyhedra In Rd, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

While in R², every two polygons of the same area are scissors congruent (i.e., they can be both decomposed into the same finite number of pair-wise congruent polygonal pieces), in R³, there are polyhedra P and P' of the same volume which are not scissors-congruent. It is therefore necessary, given two polyhedra, to check whether they are scissors-congruent (and if yes -- to find the corresponding decompositions). It is known that while there are algorithms for performing this checking-and-finding task, no such algorithm can be feasible -- their worst-case computation time grows (at least) exponentially, so …

Why Injecting Fine Dust Into A Tornado Is More Promising Than Injecting Coarse Dust: A Geometric Explanation, Octavio Lerma, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

One of the promising ways to tame a tornado is to inject dust into it. Somewhat counter-intuitively, injecting coarse dust only makes the tornado stronger, while injecting fine dust can indeed help in the taming. This difference has been explained by a mathematical analysis of the corresponding equations, but (in contrast to the usual physics practice) this mathematical analysis has not yet been accompanied by a simple qualitative physical explanation. We show that such a simple explanation can be obtained if we analyze the problem of taming tornados from the geometric viewpoint.

A Simple Geometric Model Provides A Possible Quantitative Explanation Of The Advantages Of Immediate Feedback In Student Learning, Octavio Lerma, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

Calculus is a known bottleneck for many students studying science and engineering. Various techniques have been developed to enhance the students' success. A recent study published in the Notices of American Mathematical Society showed that only one factor determines the success of a technique: the presence of immediate feedback. On average, students who receive immediate feedback learn twice faster than students who are taught in a more traditional way, with a serious feedback only once or twice a semester (after a test).

The very fact that immediate feedback is helpful is not surprising: it helps the student clear misconceptions and …

Diversity Is Beneficial For A Research Group: One More Quantitative Argument, Komsan Suriya, Tatcha Sudtasan, Tonghui Wang, Octavio Lerma, Vladik Kreinovich

Departmental Technical Reports (CS)

In this paper, we propose a natural model describing competition between two research groups of the same average research strength. The analysis of this model enables us to conclude that a more diverse group has an advantage: namely, the more diverse the group, the higher the average quality of its publications.

Zipf's Law And 7 Plus Minus 2 Principle Lead To A Possible Explanation Of Daniel's Law, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

In 1961, D. R. Daniel observed that the success of a company is usually determined by three to six major factors. This observation has led to many successful management ideas, but they leave one puzzled: why three to six? why not two or seven? In this paper, we provide a possible explanation to this puzzle; namely, we show that these numbers of factors can be derived from Zipf's Law and from the 7 plus minus 2 principle.

2tl: A Raid I/O Scheduling Algorithm For Simultaneously Providing Latency And Throughput Guarantees, Yipkei Kwok

Open Access Theses & Dissertations

It is increasingly common for applications to require that data read from and written to a shared storage system be delivered within a specified amount of time (usually milliseconds), called a latency requirement, or be delivered at a specified rate (measured in megabytes per second), called a throughput requirement. Given an input/output (I/O) workload, which consists of the streams of I/O requests of a set of applications, the storage system, via its I/O scheduler, is expected to simultaneously meet the workload's latency and throughput requirements. In addition, it is expected to provide performance guarantees, i.e., guarantees that it will meet …

Neighbor Discovery Message Hold Times For Mobile Ad Hoc Networks, Joshua Lee Mccartney

Open Access Theses & Dissertations

We present the results of an experimental study designed to understand the impact of neighbor discovery message hold times on network performance measures for a mobile ad hoc network. A physical testbed of pseudo-mobile nodes using the OLSR routing protocol was used for our experiments. We found statistically significant evidence to suggest that setting the neighbor discovery message hold times close to the neighbor discovery message interval time results in the best overall network performance.

Runtime Pipeline I/O Scheduling System For Gpu-Based Heterogeneous Architectures, Julio Cesar Olaya

Open Access Theses & Dissertations

Heterogeneous architectures can improve the performance of applications with computationally intensive operations. Even when these architectures may reduce the execution time of applications, there are opportunities for additional performance improvement as the memory hierarchies of the central processor cores and the coprocessor cores are separate. Applications running on heterogeneous architectures where graphics processing units (GPUs) execute throughput-intense, data-parallel operations may run in a single address space provided by unified virtual addressing or expand the upper bounds of scalability and high performance computing by explicitly partitioning and transferring data across orthogonal host and device address spaces. For explicit handling, applications must …

Platform-Independent Data Locality Analysis To Predict Cache Performance On Abstract Hardware Platforms, Sonish Shrestha

Open Access Theses & Dissertations

This research is part of a co-design project that has the goal of designing hardware systems to match application requirements and efficiently mapping applications to hardware. This thesis is focused on optimizing the platform cache memory hierarchy configuration. To determine application requirements, we characterize the application using platform- independent locality metrics. Next we use locality data and an analytical model to predict cache an application performance of sequential versions of application codes for various cache configurations. After using an analytical model to select a candidate set of cache memory hierarchy configurations, we used architectural simulation to test the selection for …

Multi-Dimensional Emotion Recognition From Geometry And Color Information, Geovany A. Ramirez

Open Access Theses & Dissertations

Emotions play a fundamental role in everyday interactions among humans. Humans are adept at expressing themselves and interpreting others through a multi-modal, subtle and complex process using non-verbal cues including speech prosody, facial expression, eye gaze, body gestures, head motion, posture, and skin color changes. However, recognizing the affective state of humans is a difficult task for computers.

Automatic emotion recognition has focused on analysis of the six discrete basic emotions: happiness, sadness, surprise, fear, anger and disgust. However, humans express more complex and subtle affective states such as confusion, shame, pleasure, anxiety or depression. Therefore, a different representation based …

Essays On The Digital Divide, Belal Abdelfattah

Open Access Theses & Dissertations

The digital divide is a phenomenon that is globally persistent, despite rapidly decreasing costs in technology. While much of the variance in the adoption and use of information communication technology (ICT) that defines the digital divide can be explained by socioeconomic and demographic variables, there is still significant unaccounted variance that needs to be explained if the world's population is expected to be brought more fully into the digital age. The present research addresses this need with three cross-country studies. Study 1 primarily investigates the time individuals spend with traditional media sources as a likely explanation for their frequency of …

A Visualization And Simulation Tool That Will Generate Effective Patrolling Strategies To Protect The U.S. Borders From Illegal Intrusion Using Game Theoretic Methods And Models, Eric Gutierrez

Open Access Theses & Dissertations

In the recent decade, the United States Border Patrol has increased the presence of border security officers at points of entry along the U.S.- Mexico border. In response to this increased presence of border security officials at ports of entries, illegal intruders have rerouted their intrusions in between ports of entry, in harsher terrain areas of the U.S. (e.g., the Arizona desert). The U.S. Border Patrol could benefit from a tool that plans effective border patrolling routes, and helps border security officials to make risk-based decisions for resource allocation. We are currently developing a tool called Genetic Algorithm for a …

Contributions To Global Optimization Using Interval Methods And Speculation, Angel Fernando Garcia Contreras

Open Access Theses & Dissertations

Most electronic devices we are familiar with, such as cell phones and computers, are small and require similarly small electronic components arranged and connected in small areas. Finding the right size and arrangement of the components inside a device can be a challenge. The manufacturing process of the components limits their possible size, some components have specific needs to operate at a certain speed, and the total area of the device is also limited. In portable devices, these designs have one important objective: that the entire device consumes the minimum amount of electricity possible, so the device can keep functioning …

An Optimization Of Neighbor Discovery In Mobile Ad Hoc Networks, Felipe Jovel

Open Access Theses & Dissertations

This Thesis aims to improve the performance of Mobile Ad Hoc Networks (MANETs) that use soft-state signaling for neighbor discovery, specifically OLSR. In particular, it uses simulations and previous work based on experiments conducted on a physical test bed to study the behavior of the neighbor-discovery algorithm used by OLSR to identify and explore ways to optimize the neighbor-discovery process. Candidate optimizations include the actual and relative settings of the refresh and expiry timers used by the algorithm.

Previous studies focused on understanding how the settings of the algorithms Hello Interval (δ) and TC Interval refresh timers affect network performance …

Public Social Network Sites And Social Recruiting, Abby Peters

Open Access Theses & Dissertations

Social network sites (SNSs) are an increasingly popular form of social media used by individuals and organizations. As these platforms continue to transform the way people communicate with one another, they are simultaneously revolutionizing the way individuals interact with organizations. Part of this dramatic change is apparent in the processes by which organizations are recruiting employees and job seekers are pursuing employment. To investigate these phenomena, I employed the diffusion of innovations theory in a SNS context to examine the relationship between organizations' use of their corporate career website and their use of SNSs as recruiting sources. Subsequently, I used …

Strongly Coupled Quark Matter: Chiral Symmetry Breaking In A Magnetic Field, And Eos In The Bec-Bec Crossover, Israel Portillo Vazquez

Open Access Theses & Dissertations

We explore chiral symmetry breaking in a magnetic field within a Nambu-Jona-Lasinio model of interacting massless quarks including tensor channels. The new interaction channels are opened up through Fierz identities due to the breaking of the rotational symmetry by the magnetic field. We demonstrate that the magnetic catalysis of chiral symmetry breaking leads to the generation of two independent condensates, the conventional chiral condensate and a spin-one condensate. While the chiral condensate generates a dynamical fermion mass, the spin-one condensate gives rise to a dynamical anomalous magnetic moment for the fermions. We also investigate the possibility of a crossover from …

Three Essays On Social/Political Structures And Icts Use, Seungeui Ryu

Open Access Theses & Dissertations

My research identifies how social structures affect the use of the Internet and/or a mobile chat application and how the Internet impacts the political structure of a nation. In my first essay of the 3-essay Dissertation, I am designing three models based on social structure theory that are used to study the Internet and a popular mobile chat application's use by managers in South Korea, with the help of a survey instrument. In my first essay, the contribution is on i) testing a model of manager's personal behavior on Information and Communication Technology (ICT) use at the individual level involving …

Permit Tool: Development Of An Algorithm To Determine Performance Life Of Hma Mixes In Texas, Luis Alberto Torres Escobedo

Open Access Theses & Dissertations

A number of hot mix asphalt (HMA) types, such as permeable friction course (PFC), stone mastic asphalt (SMA), performance design mixes and conventional dense graded mixes are currently used to construct or overlay Texas roads. One of the important inputs into current pavement design programs used by the Texas Department of Transportation (TxDOT) is the performance lives of HMA mixes. To determine the best mix type for a particular job or to analyze the performance of a mix or a road, a new system can be developed to rationally quantify the HMA mix performance. This system must have access to …

Fuzziness And Bayesian Analysis In Engineering, Matthias Stein, Michael Beer, Vladik Kreinovich

Departmental Technical Reports (CS)

An engineering analysis requires a realistic quantification of all input information. The amount and quality of the available information dictates the uncertainty model and its associated quantification concept. For inconsistent information, a distinction between probabilistic and non-probabilistic characteristics is beneficial. In this distinction, uncertainty refers to probabilistic characteristics and non-probabilistic characteristics are summarized as imprecision. When uncertainty and imprecision occur simultaneously, the uncertainty model fuzzy randomness appears useful. In a Bayesian approach the fuzzy probabilistic model provides the opportunity to take account of imprecision in data and in prior expert knowledge. The Bayesian approach ex-tended to inconsistent information is demonstrated …

"And"- And "Or"-Operations For "Double", "Triple", Etc. Fuzzy Sets, Hung T. Nguyen, Vladik Kreinovich, Olga Kosheleva

Departmental Technical Reports (CS)

In the traditional fuzzy logic, the expert's degree of confidence d(A & B) in a complex statement A & B (or A\/B) is uniquely determined by his/her degrees of confidence d(A) and d(B) in the statements A and B, as f_&(d(A),d(B)) for an appropriate "and"-operation (t-norm). In practice, for the same degrees d(A) and d(B), we may have different degrees d(A & B) depending on the relation between A and B. The best way to take this relation into account is to explicitly elicit the corresponding degrees d(A & B) and d(A\/B), i.e., to come up with "double" …

Towards Designing Optimal Individualized Placement Tests, Octavio Lerma, Olga Kosheleva, Shahnaz Shahbazova, Vladik Kreinovich

Departmental Technical Reports (CS)

To find the current level of a student's knowledge, we use a sequence of problems of increasing complexity; if a student can solve a problem, the system generates a more complex one; if a student cannot solve a problem, the system generates an easier one. To find a proper testing scheme, we must take into account that every time a student cannot solve a problem, he/she gets discouraged. To take this into account, we define an overall effect on a student by combining "positive" and "negative" problems with different weights, and we design a testing scheme which minimizes this effect.

Why Triangular Membership Functions Work Well In F-Transform: A Theoretical Explanation, Jaime Nava, Vladik Kreinovich

Departmental Technical Reports (CS)

In many practical applications, it is useful to represent a signal or an image by its average values on several fuzzy sets. The corresponding {\em F-transform} technique has many useful applications in signal and image processing. In principle, we can use different membership functions. Somewhat surprisingly, in many applications, the best results occur when we use triangular membership functions. In this paper, we provide a possible theoretical explanation for this empirical phenomenon.