Computer Engineering Commons^™

A Tutorial On Functional Program Verification, Yoonsik Cheon, Melisa Vela

Departmental Technical Reports (CS)

This document gives a quick tutorial introduction to a functional program verification. In the functional program verification, a program is viewed as a mathematical function from one program state to another, and proving its correctness is essentially comparing two mathematical functions, the function computed by the program and the specification of the program, called an intended function. The reader is assumed to have some programming experience and to be familiar with such mathematical concepts as sets and functions.

From Interval And Probabilistic Granules To Granules Of Higher Order, Vladik Kreinovich

Departmental Technical Reports (CS)

Constructive mathematics, mathematics in which the existence of an object means that that we can actually construct this object, started as a heavily restricted version of mathematics, a version in which many commonly used mathematical techniques (like the Law of Excluded Middle) were forbidden to maintain constructivity. Eventually, it turned out that not only constructive mathematics is not a weakened version of the classical one -- as it was originally perceived -- but that, vice versa, classical mathematics can be viewed as a particular (thus, weaker) case of the constructive one. Crucial results in this direction were obtained by M. …

Visualization To Support The Discovery Of Prosodic Contours Related To Turn-Taking, Nigel Ward, Joshua L. Mccartney

Departmental Technical Reports (CS)

Some meaningful prosodic patterns can be usefully represented with pitch contours, however the development of such descriptions is a labor-intensive process. To assist in the discovery of contours, visualization tools may be helpful. Edlund et al. (2009) presented the idea of superimposing hundreds of pitch curves from a corpus as a way to see the overall patterns. In this paper we refine and extend this method and illustrate its utility in the discovery of a prosodic cue to back-channels in Chinese. We also discuss issues in relating a contour-based description to one in terms of a conjunction of features, and …

Computing Standard-Deviation-To-Mean And Variance-To-Mean Ratios Under Interval Uncertainty Is Np-Hard, Sio-Long Lo

Departmental Technical Reports (CS)

Once we have a collection of values x1, ..., ,xn corresponding a class of objects, a usual way to decide whether a new object with the value x of the corresponding property belongs to this class is to check whether the value x belongs to interval [E - k0 * s, E + k0 * s], where E = (1/n) * (x1 + ... + xn) is the sample mean, V = s^2 = (1/n) * ((x1 - E)^2 + ... + (xn - E)^2) is the sample variance, and the parameter k0 is determined by the degree of confidence …

Iphone 3gs Forensics: Logical Analysis Using Apple Itunes Backup Utility, Mona Bader, Ibrahim Baggili

Electrical & Computer Engineering and Computer Science Faculty Publications

The iPhone mobile is used worldwide due to its enhanced computing capabilities, increased storage capacity as well as its attractive touch interface. These characteristics made the iPhone a popular smart phone device. The increased use of the iPhone lead it to become a potential source of digital evidence in criminal investigations. Therefore, iPhone forensics turned into an essential practice for forensic and security practitioners today. This research aimed at investigating and examining the logical backup acquisition of the iPhone 3GS mobile device using the Apple iTunes backup utility. It was found that significant data of forensic value such as e-mail …

Cloud Computing:Strategies For Cloud Computing Adoption, Faith Shimba

Dissertations

The advent of cloud computing in recent years has sparked an interest from different organisations, institutions and users to take advantage of web applications. This is a result of the new economic model for the Information Technology (IT) department that cloud computing promises. The model promises a shift from an organisation required to invest heavily for limited IT resources that are internally managed, to a model where the organisation can buy or rent resources that are managed by a cloud provider, and pay per use. Cloud computing also promises scalability of resources and on-demand availability of resources.

Although, the adoption …

A Cross-Layer Modification To The Dsr Routing Protocol In Wireless Mesh Networks, Mustafa Ramadhan

Doctoral

A cross-layer modification to the DSR routing protocol that finds high throughput paths in WMNs has been introduced in this work. The Access Efficiency Factor (AEF) has been introduced in this modification as a local congestion avoidance metric for the DSR routing mechanism as an alternative to the hop count (Hc) metric. In this modification, the selected path is identified by finding a path with the highest minimum AEF (max_min_AEF) value. The basis of this study is to compare the performance of the Hc and max_min_AEF as routing metrics for the DSR protocol in WMNs using the OPNET modeler. Performance …

Sql Querie Recommendations: A Query Fragment-Based Approach, Jayad Akbarnejad, Magdalini Eirinaki, Suju Koshy, Duc On, Neoklis Polyzotis

Faculty Publications

Relational database systems are becoming increasingly popular in the scientific community to support the interactive exploration of large volumes of data. In this scenario, users employ a query interface (typically, a web-based client) to issue a series of SQL queries that aim to analyze the data and mine it for interesting information. First-time users, however, may not have the necessary knowledge to know where to start their exploration. Other times, users may simply overlook queries that retrieve important information. In this work we describe a framework to assist non-expert users by providing personalized query recommendations. The querying behavior of the …

Personal Vs. Social, Magdalini Eirinaki

Faculty Publications

The last few years we witnessed an impressive growth in social networks and in applications that add value to their amassed information. At the same time, the continuing expansion of mobile platforms and applications (e.g. iPhone), combined with the overwhelming supply of information and services, makes effective personalization and context-awareness much required features. One may consider "personal" and "social" data management as comprising two distinct directions with conflicting characteristics. However, it can be argued that they complement each other and that in future applications they will ultimately converge. This "personal vs. social" predicament presents a number of interesting topics that …

Online Drift Compensation For Chemical Sensors Using Estimation Theory, Thomas H. Wenzel, Arnold Kweku Mensah-Brown, Fabien Josse, Edwin E. Yaz

Electrical and Computer Engineering Faculty Research and Publications

Sensor drift from slowly changing environmental conditions and other instabilities can greatly degrade a chemical sensor's performance, resulting in poor identification and analyte quantification. In the present work, estimation theory (i.e., various forms of the Kalman filter) is used for online compensation of baseline drift in the response of chemical sensors. Two different cases, which depend on the knowledge of the characteristics of the sensor system, are studied. First, an unknown input is considered, which represents the practical case of analyte detection and quantification. Then, the more general case, in which the sensor parameters and the input are both unknown, …

Architecture And Compiler Support For Leakage Reduction Using Power Gating In Microprocessors, Soumyaroop Roy

USF Tampa Graduate Theses and Dissertations

Power gating is a technique commonly used for runtime leakage reduction in digital CMOS circuits. In microprocessors, power gating can be implemented by using sleep transistors to selectively deactivate circuit modules when they are idle during program execution. In this dissertation, a framework for power gating arithmetic functional units in embedded microprocessors with architecture and compiler support is proposed. During compile time, program regions are identified where one or more functional units are idle and sleep instructions are inserted into the code so that those units can be put to sleep during program execution. Subsequently, when their need is detected …

Beyond Ning: Rolling Your Own Social Network, Aaron Sumner

SIDLIT Conference

Ning has recently announced plans to discontinue its free service, requiring network creators to pay for service or leave Ning altogether. In this session we'll look at how this decision affects educational users of Ning, as well as alternative, DIY social networking software packages such as Elgg, Buddypress, and Community Engine.

Cantor's Paradise Regained: Constructive Mathematics From Brouwer To Kolmogorov To Gelfond, Vladik Kreinovich

Departmental Technical Reports (CS)

Constructive mathematics, mathematics in which the existence of an object means that that we can actually construct this object, started as a heavily restricted version of mathematics, a version in which many commonly used mathematical techniques (like the Law of Excluded Middle) were forbidden to maintain constructivity. Eventually, it turned out that not only constructive mathematics is not a weakened version of the classical one -- as it was originally perceived -- but that, vice versa, classical mathematics can be viewed as a particular (thus, weaker) case of the constructive one. Crucial results in this direction were obtained by M. …

Constraint-Related Reinterpretation Of Fundamental Physical Equations Can Serve As A Built-In Regularization, Vladik Kreinovich, Juan Ferret, Martine Ceberio

Departmental Technical Reports (CS)

Many traditional physical problems are known to be ill-defined: a tiny change in the initial condition can lead to drastic changes in the resulting solutions. To solve this problem, practitioners regularize these problem, i.e., impose explicit constraints on possible solutions (e.g., constraints on the squares of gradients). Applying the Lagrange multiplier techniques to the corresponding constrained optimization problems is equivalent to adding terms proportional to squares of gradients to the corresponding optimized functionals. It turns out that many optimized functionals of fundamental physics already have such squares-of-gradients terms. We therefore propose to re-interpret these equations -- by claiming that they …

Performance Measures In Acousto-Optic Chaotic Signal Encryption System Subject To Parametric Variations And Additive Noise, Monish Ranjan Chatterjee, Anjan K. Ghosh, Mohammed A. Al-Saedi

Electrical and Computer Engineering Faculty Publications

Signal encryption and recovery using chaotic optical waves has been a subject of active research in the past 10 years. Since an acousto-optic Bragg cell with zeroth- and first-order feedback exhibits chaotic behavior past the threshold for bistability, such a system was recently examined for possible chaotic encryption using a low-amplitude sinusoidal signal applied via the bias input of the sound cell driver.

Subsequent recovery of the message signal was carried out via a heterodyne strategy employing a locally generated chaotic carrier, with threshold parameters matched to the transmitting Bragg cell. The simulation results, though encouraging, were limited to relatively …

Consideration Of Dispersion And Group Velocity Dispersion In The Determination Of Velocities Of Electromagnetic Propagation, Monish Ranjan Chatterjee, Partha P. Banerjee

Electrical and Computer Engineering Faculty Publications

Electromagnetic (EM) propagation velocities play an important role in the determination of power and energy flow in materials and interfaces. It is well known that group and phase velocities need to be in opposition in order to achieve negative refractive index.

Recently, we have shown that considerable differences may exist in phase, group and signal/energy velocities for normal and anomalous dispersion, especially near dielectric resonances. This paper examines the phase and group velocities in the presence of normal and anomalous dispersion, and group velocity dispersion (GVD), which requires introduction of the second order coefficient in the permittivity and permeability models.

Studies In The Use Of Time Into Utterance As A Predictive Feature For Language Modeling, Nigel Ward, Alejandro Vega

Departmental Technical Reports (CS)

In (Ward and Vega 2008) we examined how how word probabilities vary with time into utterance, and proposed a method for using this information to improve a language model. In this report we examine some ancillary issues in the modeling and exploitation of these regularities.

Functional Specification And Verification Of Object-Oriented Programs, Yoonsik Cheon

Departmental Technical Reports (CS)

One weakness of Hoare-style verification techniques based on first-order predicate logic is that reasoning is backward from postconditions to preconditions. A natural, forward reasoning is possible by viewing a program as a mathematical function that maps one program state to another. This functional program verification technique requires a minimal mathematical background as it uses equational reasoning based on sets and functions. Thus, it can be easily taught and used in practice. In this paper, we formalize a functional program specification and verification technique and extend it for object-oriented programs. Our approach allows one to formally specify and verify the behavior …

Integrating Recommender Information In Social Ecosystems Decisions, Renato A C Capuruco, Luiz Fernando Capretz

Electrical and Computer Engineering Publications

The exploration of online social networks whose members share mutual recommendations and interactions is a time-dependent and contextual-based process which aims to predict the social status among members, ultimately improving the network's discoverability to achieve societal gain. To address the difficulties associated with the process, this article presents an integrated recommender model whose statements are time-dependent, interaction-aware, and social context-sensitive. The originality of the proposed model stems from the integration of the predictive recommender, social networks, and interaction components. Each model is developed based on: (1) a time history and decay algorithm to consider the decreasing intensity of recommendations among …

An Empirical Study On The Procedure To Derive Software Quality Estimation Models, Jie Xu, Danny Ho, Luiz Fernando Capretz

Electrical and Computer Engineering Publications

Software quality assurance has been a heated topic for several decades. If factors that influence software quality can be identified, they may provide more insight for better software development management. More precise quality assurance can be achieved by employing resources according to accurate quality estimation at the early stages of a project. In this paper, a general procedure is proposed to derive software quality estimation models and various techniques are presented to accomplish the tasks in respective steps. Several statistical techniques together with machine learning method are utilized to verify the effectiveness of software metrics. Moreover, a neuro-fuzzy approach is …

Why Ellipsoid Constraints, Ellipsoid Clusters, And Riemannian Space-Time: Dvoretzky's Theorem Revisited, Karen Villaverde, Olga Kosheleva, Martine Ceberio

Departmental Technical Reports (CS)

In many practical applications, we encounter ellipsoid constraints, ellipsoid-shaped clusters, etc. A usual justification for this ellipsoid shape comes from the fact that many real-life quantities are normally distributed, and for a multi-variate normal distribution, a natural confidence set (containing the vast majority of the objects) is an ellipsoid. However, ellipsoid appear more frequently than normal distributions (which occur in about half of the cases). In this paper, we provide a new justification for ellipsoids based on a known mathematical result -- Dvoretzky's Theorem.

Towards An Efficient Bisection Of Ellipsoids, Paden Portillo, Martine Ceberio, Vladik Kreinovich

Departmental Technical Reports (CS)

Constraints are often represented as ellipsoids. One of the main advantages of such constrains is that, in contrast to boxes, over which optimization of even quadratic functions is NP-hard, optimization of a quadratic function over an ellipsoid is feasible. Sometimes, the area described by constrains is too large, so it is reasonable to bisect this area (one or several times) and solve the optimization problem for all the sub-areas. Bisecting a box, we still get a box, but bisecting an ellipsoid, we do not get an ellipsoid. Usually, this problem is solved by enclosing the half-ellipsoid in a larger ellipsoid, …

Facial Expression Recognition System, Ewa Piatkowska

Technical Reports

This thesis describes the problem of facial expression recognition in the field of computer vision. Firstly, the psychological background of a problem is presented. Then, the idea of facial expression recognition system (FERS) is outlined and the requirements of such system are specified. The FER system consists of 3 stages: face detection, feature extraction and expression recognition. Methods proposed in literature are reviewed for each stage of a system. Finally, the design and implementation of my system are explained. The face detection algorithm used in the system is based on work by Viola and Jones [13]. The expressions are described …

Simsight: A Virtual Machine Based Dynamic Call Graph Generator, Xueling Chen

School of Computing: Dissertations, Theses, and Student Research

One problem with using component-based software development approach is that once software modules are reused over generations of products, they form legacy structures that can be challenging to understand, making validating these systems difficult. Therefore, tools and methodologies that enable engineers to see interactions of these software modules will enhance their ability to make these software systems more dependable. To address this need, we propose SimSight, a framework to capture dynamic call graphs in Simics, a widely adopted commercial full-system simulator. Simics is a software system that simulates complete computer systems. Thus, it performs nearly identical tasks to …

Managing Large Data Sets Using Support Vector Machines, Ranjini Srinivas

School of Computing: Dissertations, Theses, and Student Research

Hundreds of Terabytes of CMS (Compact Muon Solenoid) data are being accumulated for storage day by day at the University of Nebraska-Lincoln, which is one of the eight US CMS Tier-2 sites. Managing this data includes retaining useful CMS data sets and clearing storage space for newly arriving data by deleting less useful data sets. This is an important task that is currently being done manually and it requires a large amount of time. The overall objective of this study was to develop a methodology to help identify the data sets to be deleted when there is a requirement for …

Design Of A Transtibial Prosthesis Utilizing Active And Passive Components In Conjunction With A Four-Bar Mechanism, Bryan Bergelin

Master's Theses (2009 -)

This thesis outlines the design and testing of a powered ankle prosthesis which utilizes a four-bar mechanism in conjunction with a spiral torsion spring and a servo motor that mimics non-amputee (normal) ankle moments during the stance phase of gait. Previous research has shown that this novel approach is feasible, but the proof-of-concept prototype was not designed to be able to be worn by an amputee due to size, strength and mobility limitations. The goal of this research was to redesign the transtibial prosthesis to fit the requirements of the targeted amputee population. A preliminary virtual prosthesis was designed using …

Asynchronous Mips Processors: Educational Simulations, Robert L. Webb

Master's Theses

The system clock has been omnipresent in most mainstream chip designs. While simplifying many design problems the clock has caused the problems of clock skew, high power consumption, electromagnetic interference, and worst-case performance. In recent years, as the timing constraints of synchronous designs have been squeezed ever tighter, the efficiencies of asynchronous designs have become more attractive. By removing the clock, these issues can be mitigated. How- ever, asynchronous designs are generally more complex and difficult to debug. In this paper I discuss the advantages of asynchronous processors and the specifics of some asynchronous designs, outline the roadblocks to asynchronous …

Hardware Microkernels - A Novel Method For Constructing Operating Systems For Heterogeneous Multi-Core Platforms, Jason M. Agron

Graduate Theses and Dissertations

Today's standard operating systems (OSes) do not have the proper structure, nor support for executing on heterogeneous multi- and many-core platforms. These deficiencies manifest in symptomatic issues that range from relatively low-level application binary interface (ABI) compatibility problems, to higher-level concerns such as application programmer interface (API) compatibility, synchronization, and caching issues. These issues in turn reflect back up to the programmer through a lack of a standard set of OS services. Non-uniformities in the hardware architecture are also reflected back into the programming model. In total these issues combined break down the most fundamental benefit of modern operating systems; …

Pattern Recognition For Fault Detection, Classification, And Localization In Electrical Power Systems, Qais Hashim Alsafasfeh

Dissertations

The longer it takes to identify and repair a fault, the more damage may result in the electrical power system, especially in periods of peak loads, which could lead to the collapse of the system, causing the power outage to extend for a longer period and larger parts of the electrical network. Reducing the outage time and immediate restoration of service can be achieved if the fault type and location are determined in a timely and precise manner.

An integrated algorithm that is based on generating unique signatures from the electric current signal to detect, classify, and localize a fault …

Investigating Perceptions Of A Location-Based Annotation System, Huynh Nhu Hop Quach, Khasfariyati Razikin, Dion Hoe-Lian Goh, Thi Nhu Quynh Kim, Tan Phat Pham, Yin-Leng Theng, Ee-Peng Lim

Research Collection School Of Computing and Information Systems

We introduce MobiTOP, a Web-based system for organizing and retrieving hierarchical location-based annotations. Each annotation contains multimedia content (such as text, images, video) associated with a location, and users are able to annotate existing annotations to an arbitrary depth, in effect creating a hierarchy. An evaluation was conducted on a group of potential users to ascertain their perceptions of the usability of the application. The results were generally positive and the majority of the participants saw MobiTOP as a useful platform to share location-based information. We conclude with implications of our work and opportunities for future research.