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2015

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Articles 1561 - 1590 of 2105

Full-Text Articles in Computer Sciences

An Accelerated And Accurate Three-Dimensional Ray Tracing Using Red-Black Tree With Facet Mining And Object Bouncing Techniques, Mohammad Jakirul Islam, Ahmed Wasif Reza, Kamarul Ariffin Noordin, Kaharudin Dimyati, Abu Sulaiman Mohammad Zahid Kausar Jan 2015

An Accelerated And Accurate Three-Dimensional Ray Tracing Using Red-Black Tree With Facet Mining And Object Bouncing Techniques, Mohammad Jakirul Islam, Ahmed Wasif Reza, Kamarul Ariffin Noordin, Kaharudin Dimyati, Abu Sulaiman Mohammad Zahid Kausar

Turkish Journal of Electrical Engineering and Computer Sciences

Recent trends show that it is a major challenge to predict the exact propagation path accurately and efficiently for three-dimensional (3D) indoor environments. Therefore, this study introduces a new 3D ray tracing algorithm based on a red-black tree with facet mining and object bouncing techniques. The red-black tree data structure offers a faster object searching operation while repeatedly performing intersection tests. On the other hand, extensive ray-facet intersection tests can be eliminated by using object and facet bouncing techniques, whereas the facet mining makes it easier to trace the transmitted ray paths accurately. The proposed method is compared with ray …


Mppt Of Pv Array Using Stepped-Up Chaos Optimization Algorithm, Lihua Wang, Xueye Wei, Yuqin Shao, Tianlong Zhu, Junhong Zhang Jan 2015

Mppt Of Pv Array Using Stepped-Up Chaos Optimization Algorithm, Lihua Wang, Xueye Wei, Yuqin Shao, Tianlong Zhu, Junhong Zhang

Turkish Journal of Electrical Engineering and Computer Sciences

In order to achieve maximum efficiency, a maximum power point tracking (MPPT) scheme should be applied in photovoltaic systems. Among all the MPPT schemes, the chaos optimization scheme is one of the hot topics in recent years. In this study, a novel stepped-up chaos optimization algorithm is presented. A chaos mapping $x_{n+1} =\mu \sin (\pi x_{n} )$ is used as a chaos generator to produce a chaos variable. In the process of MPPT, a coarse search is done to find the current optimal solution in a certain range, and then a fine search reduces the space of optimized variables. Compared …


A Taste Of Armageddon: When Warring Is Done By Drones And Robots, Brian Stiltner Jan 2015

A Taste Of Armageddon: When Warring Is Done By Drones And Robots, Brian Stiltner

Philosophy, Theology and Religious Studies Faculty Publications

Discusses the increasing use of drones and weaponized robots. Argues that the international community must put firm ethical guidelines in place before the technology becomes rampant.


A Comparative Performance Evaluation Of Various Approaches For Liver Segmentation From Spir Images, Evgi̇n Göçeri̇, Mehmet Zübeyi̇r Ünlü, Oğuz Di̇cle Jan 2015

A Comparative Performance Evaluation Of Various Approaches For Liver Segmentation From Spir Images, Evgi̇n Göçeri̇, Mehmet Zübeyi̇r Ünlü, Oğuz Di̇cle

Turkish Journal of Electrical Engineering and Computer Sciences

Developing a robust method for liver segmentation from magnetic resonance images is a challenging task because of the similar intensity values between adjacent organs, the geometrically complex liver structure, and injection of contrast media. Most importantly, a high anatomical variability of a healthy or diseased liver is a major challenge in defining the exact boundaries of the liver. Several artifacts of pulsation, motion, and partial volume effects are also among the variety of factors that make automatic liver segmentation difficult. In this paper, we present an overview of liver segmentation methods in magnetic resonance images and show comparative results of …


A Mobile And Web Application-Based Recommendation System Using Color Quantization And Collaborative Filtering, Fi̇dan Kaya, Gürel Yildiz, Adnan Kavak Jan 2015

A Mobile And Web Application-Based Recommendation System Using Color Quantization And Collaborative Filtering, Fi̇dan Kaya, Gürel Yildiz, Adnan Kavak

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a recommendation system based on a mobile and web application is proposed for indoor decoration. The main contribution of this work is to apply two-stage filtering using linear matching and collaborative filtering to make recommendations. In the mobile application part, the image of the medium captured by a mobile phone is analyzed using color quantization methods, and these color analysis results along with other user-defined parameters such as height, width, and type of the product are sent to the web server. In the web application part, a large data set is first filtered via linear matching in …


A Phenomenological Study Of Computer Science Lecturers: Lived Experiences Of Curriculum Design, Arthur Sloan Jan 2015

A Phenomenological Study Of Computer Science Lecturers: Lived Experiences Of Curriculum Design, Arthur Sloan

Doctoral

This hermeneutic phenomenological study presents a description of computer science lecturers’ experiences of curriculum design of degree programmes during a time of transition in curriculum design policy, specifically in the context of Technological University Dublin (DIT). It examines the lived experiences of computer science lecturers to highlight the issues and problems relating to lecturers’ lived experiences of curriculum design, and it describes how it is to be a computer science lecturer in a time of policy change for curriculum design. The findings are that lecturers have been, and are, struggling to cope with the transition from year-long to semesterised courses, …


Context-Based Access For Infrequent Requests In Tanzania's Health Care System, Zanifa Omary Jan 2015

Context-Based Access For Infrequent Requests In Tanzania's Health Care System, Zanifa Omary

Doctoral

Access control is an important aspect of any information system. It is a way of ensuring that users can only access what they are authorised to and no more. This can be achieved by granting users access to resources based on pre-defined organisational and legislative rules. Although access control has been extensively studied, and as a result, a wide range of access control models, mechanisms and systems have been proposed, specific access control requirements for healthcare systems that needs to support the continuity of care in an accountable manner have not been addressed. This results in a gap between what …


Drive-Based Utility-Maximizing Computer Game Non-Player Characters, Colm Sloan Jan 2015

Drive-Based Utility-Maximizing Computer Game Non-Player Characters, Colm Sloan

Doctoral

This research examines the emergence of the five-string fiddle in contemporary North American fiddle culture within the past ten years. By interacting with leading artistlevel practitioners, the research documents the evolution and impact of the instrument to date in exploring the possibilities the five-string fiddle presents for musical performance and innovation. North American vernacular music and, in particular, the contemporary fiddle playing landscape, exemplifies virtousic and innovative idiomatic technique and improvisation as central to an overarching musical explosion, evidenced in the music of many high level, multi-stylistic contemporary practitioners. Within contemporary American fiddle performance, it is compelling to observe how …


The State Of Mobile Learning Implementation In Government Cabinet-Level Agencies And Departments, Algernon B. Corbett Jan 2015

The State Of Mobile Learning Implementation In Government Cabinet-Level Agencies And Departments, Algernon B. Corbett

CCAC Theses and Dissertations

As mobile technologies have increasingly become a part of personal and work environments, mobile learning is emerging as a viable alternative for training and education needs. Faced with the need for innovative and cost-efficient ways for training government employees, agencies and departments are considering the use of mobile learning. The availability of a wide range of mobile technology provides many options. Other than the Department of Defense, little is known about implementing mobile learning in United States government cabinet level agencies and departments. A concurrent, mixed methods case study was used to examine how organizations decide to use, implement and …


The Construction And Validation Of An M-Learning Framework For Online And Blended Learning Environments, Dick T. Hamann Jan 2015

The Construction And Validation Of An M-Learning Framework For Online And Blended Learning Environments, Dick T. Hamann

CCAC Theses and Dissertations

With the wide adoption of mobile technologies, new opportunities exist with regard to how these technologies can be used to support teaching and learning. However, there is limited empirical evidence on the use of mobile learning (m-learning) frameworks that support adult students in online and blended learning environments and consider ways to support administrators, faculty, and students in the adoption of mobile technologies for teaching and learning.

The goal was to develop and validate an m-learning framework capturing the administrative, communication, and instructional elements that must be considered when integrating m-learning technologies to support adult community college students. Using design …


Building Cloud-Based Information Systems Lab Architecture: Deriving Design Principles That Facilitate The Effective Construction And Evaluation Of A Cloud-Based Lab Environment, Thomas J. Trevethan Jan 2015

Building Cloud-Based Information Systems Lab Architecture: Deriving Design Principles That Facilitate The Effective Construction And Evaluation Of A Cloud-Based Lab Environment, Thomas J. Trevethan

CCAC Theses and Dissertations

The problem explored in this dissertation report was that at the time of this study, there were no design principles or methodologies based on design science research (DSR) available to use for artifact construction, implementation, and effective evaluation of cloud-based networking lab environments that can be used to foster hands-on technology skills in students. Primarily based on Hevner’s 7 guidelines of DSR, Peffer’s design science research methodology (DSRM), and Gregor’s IS design theory, this study forms the groundwork for the development of procedures and specifications derived from DSR literature to facilitate the construction, implementation, and evaluation of a comprehensive cloud-based …


Well-Being Technologies: Meditation Using Virtual Worlds, Laura Downey Jan 2015

Well-Being Technologies: Meditation Using Virtual Worlds, Laura Downey

CCAC Theses and Dissertations

In a technologically overloaded world, is it possible to use technology to support well-being activities and enhance human flourishing? Proponents of positive technology and positive computing are striving to answer yes to that question. However, the impact of technology on well-being remains unresolved. Positive technology combines technology and positive psychology. Positive psychology focuses on well-being and the science of human flourishing. Positive computing includes an emphasis on designing with well-being in mind as a way to support human potential. User experience (UX) is critical to positive technology and positive computing. UX researchers and practitioners are advocating for experience-driven design and …


An Empirical Investigation Into The Role That Boredom, Relationships, Anxiety, And Gratification (Brag) Play In A Driver’S Decision To Text, Nathan White Jan 2015

An Empirical Investigation Into The Role That Boredom, Relationships, Anxiety, And Gratification (Brag) Play In A Driver’S Decision To Text, Nathan White

CCAC Theses and Dissertations

Texting while driving is a growing problem that has serious, and sometimes fatal, consequences. Despite laws enacted to curb this behavior, the problem continues to grow. Discovering factors that can reduce such risky behavior can significantly contribute to research, as well as save lives and reduce property damage. This study developed a model to explore the motivations that cause a driver to send messages. The model evaluates the effects that boredom, social relationships, social anxiety, and social gratification (BRAG) have upon a driver’s frequency of typing text messages. In addition, the perceived severity of the consequences and the presence of …


A Predictive Modeling System: Early Identification Of Students At-Risk Enrolled In Online Learning Programs, Mary L. Fonti Jan 2015

A Predictive Modeling System: Early Identification Of Students At-Risk Enrolled In Online Learning Programs, Mary L. Fonti

CCAC Theses and Dissertations

Predictive statistical modeling shows promise in accurately predicting academic performance for students enrolled in online programs. This approach has proven effective in accurately identifying students who are at-risk enabling instructors to provide instructional intervention. While the potential benefits of statistical modeling is significant, implementations have proven to be complex, costly, and difficult to maintain. To address these issues, the purpose of this study is to develop a fully integrated, automated predictive modeling system (PMS) that is flexible, easy to use, and portable to identify students who are potentially at-risk for not succeeding in a course they are currently enrolled in. …


Topic Analysis And Application Using Nonnegative Matrix Factorizations (Nmf), Xin Wang Jan 2015

Topic Analysis And Application Using Nonnegative Matrix Factorizations (Nmf), Xin Wang

Legacy Theses & Dissertations (2009 - 2024)

Managing large and growing amount of information is a central goal of modern computer science. Data repositories of texts, images and videos have become widely accessible, thus necessitating good methods of retrieval, organization and exploration.


Deciding Static Inclusion For Delta-Strong And Omega [Upside Down Triangle]-Strong Intruder Theories : Applications To Cryptographic Protocol Analysis, Kimberly Ann Gero Jan 2015

Deciding Static Inclusion For Delta-Strong And Omega [Upside Down Triangle]-Strong Intruder Theories : Applications To Cryptographic Protocol Analysis, Kimberly Ann Gero

Legacy Theses & Dissertations (2009 - 2024)

In this dissertation we will be studying problems relating to indistinguishability. This topic


Visual Saliency Estimation : A Pre-Attentive Cognitive And Context-Aware Approach, Amanda Shannon Danko Jan 2015

Visual Saliency Estimation : A Pre-Attentive Cognitive And Context-Aware Approach, Amanda Shannon Danko

Legacy Theses & Dissertations (2009 - 2024)

At each glance, biological vision systems organize a tremendous amount of input and


How Three Different Generations View Modern Day Technologies, Dylan Mcgraw Jan 2015

How Three Different Generations View Modern Day Technologies, Dylan Mcgraw

Senior Seminars

No abstract provided.


Boron Nitride Colloidal Solutions, Ultralight Aerogels And Freestanding Membranes Through One-Step Exfoliation And Functionalization, Weiwei Lei, Vadym Mochalin, Dan Liu, Si Qin, Yury G. Gogotsi, Ying Chen Jan 2015

Boron Nitride Colloidal Solutions, Ultralight Aerogels And Freestanding Membranes Through One-Step Exfoliation And Functionalization, Weiwei Lei, Vadym Mochalin, Dan Liu, Si Qin, Yury G. Gogotsi, Ying Chen

Chemistry Faculty Research & Creative Works

Manufacturing of aerogels and membranes from hexagonal boron nitride (h-BN) is much more difficult than from graphene or graphene oxides because of the poor dispersibility of h-BN in water, which limits its exfoliation and preparation of colloidal solutions. Here, a simple, one-step mechano-chemical process to exfoliate and functionalize h-BN into highly water-dispersible, few-layer h-BN containing amino groups is presented. The colloidal solutions of few-layer h-BN can have unprecedentedly high concentrations, up to 30 mg ml-1, and are stable for up to several months. They can be used to produce ultralight aerogels with a density of 1.4 mg cm …


Power And Hotspot Modeling For Modern Gpus, Md Mainul Hassan Jan 2015

Power And Hotspot Modeling For Modern Gpus, Md Mainul Hassan

Electronic Theses and Dissertations

As General Purpose GPUs (GPGPU) are increasingly becoming a prominent component of high performance computing platforms, power and thermal dissipation are getting more attention. The trade-offs among performance, power, and heat must be well modeled and evaluated from the early stage of GPU design. This necessitates a tool that allows GPU architects to quickly and accurately evaluate their design. There are a few models for GPU power but most of them estimate power at a higher level than architecture, which are therefore missing hardware reconfigurability. In this thesis, we propose a framework that models power and heat dissipation at the …


Specification And Mechanical Verification Of Performance Profiles Of Software Components, Nighat Yasmin Jan 2015

Specification And Mechanical Verification Of Performance Profiles Of Software Components, Nighat Yasmin

Electronic Theses and Dissertations

Software performance predictability is vital to a system design and unpredictable performance is a leading cause of software failure. The emphasis of this dissertation is on verification that component-based software performs as specified. Performance profiles (specifications) depend on functional specifications and are necessary for all components for modular verification. Modular verification process is scalable because it uses profiles as contracts and allows verification of a single component in isolation with the assumption that any underlying component would have already been verified or will be verified to meet its specifications independently. This dissertation presents an integration of performance specification (profiles) with …


Building An Islamic Financial Information System Based On Policy Managements, Izzat M. Alsmadi, M. Zarour Jan 2015

Building An Islamic Financial Information System Based On Policy Managements, Izzat M. Alsmadi, M. Zarour

Computer Science Faculty Publications (Archived)

For many banks and customers in the Middle East and Islamic world, the availability and the ability to apply Islamic Shariah rules on financial activities is very important. In some cases, business and technical barriers can limit the ability to apply and offer financial services that are implemented according to Shariah rules. In this paper, we discuss enforcing Shariah rules from information technology viewpoint and show how such rules can be implemented and enforced in a financial establishment. Security authorization standard XACML is extended to consider Shariah rules. In this research XACML architecture, that is used and applied in many …


Design, Testing And Implementation Of A New Authentication Method Using Multiple Devices, Cagri Cetin Jan 2015

Design, Testing And Implementation Of A New Authentication Method Using Multiple Devices, Cagri Cetin

USF Tampa Graduate Theses and Dissertations

Authentication protocols are very common mechanisms to confirm the legitimacy of someone’s or something’s identity in digital and physical systems.

This thesis presents a new and robust authentication method based on users’ multiple devices. Due to the popularity of mobile devices, users are becoming more likely to have more than one device (e.g., smartwatch, smartphone, laptop, tablet, smart-car, smart-ring, etc.). The authentication system presented here takes advantage of these multiple devices to implement authentication mechanisms. In particular, the system requires the devices to collaborate with each other in order for the authentication to succeed. This new authentication protocol is robust …


Plus: A Unique Personalized Literature Recommender System, Jingwen Zhang Jan 2015

Plus: A Unique Personalized Literature Recommender System, Jingwen Zhang

Wayne State University Theses

There are massive research papers published from various of disciplines every year, and people who are engaged in scientific research usually have to spend a large amount of time on searching and finding the papers that they are interested in.

In this thesis, we illustrated a unique personalized literature recommender system (PLUS) which was proposed to predict users' personal research interests and recommend the latest papers to them as much as possible. The system shows advantages in four aspects: (1) it takes multiple sources that could reflect a user's personal research interest as the input; (2) it prevents the recommendations …


Comparison Of Lazy Controller And Constant Bandwidth Server For Temperature Control, Zhen Sun Jan 2015

Comparison Of Lazy Controller And Constant Bandwidth Server For Temperature Control, Zhen Sun

Wayne State University Theses

Temperature control plays an important role in building control systems; there are

numerous methods for controlling temperature. Recently, a popular controller is the

lazy controller which proposed by Truong et al. However, by applying lazy control, the

temperature is not stable since this controller simply lets temperature increase or decrease

until it reaches the upper or lower temperature thresholds. We seek a heater-control

schedule that can make room temperatures more stable. The Constant Bandwidth Server

(CBS) was developed to handle soft real-time tasks characterized by the execution time

and period. By employing the concepts of CBS, we can derive a …


Evaluation Of An Architectural-Level Approach For Finding Security Vulnerabilities, Mohammad Anamul Haque Jan 2015

Evaluation Of An Architectural-Level Approach For Finding Security Vulnerabilities, Mohammad Anamul Haque

Wayne State University Theses

The cost of security vulnerabilities of a software system is high. As a result,

many techniques have been developed to find the vulnerabilities at development time. Of particular interest are static analysis techniques that can consider all possible executions of a system. But, static analysis can suffer from a large number of false positives.

A recently developed approach, Scoria, is a semi-automated static analysis that requires security architects to annotate the code, typecheck the annotations, extract a hierarchical object graph and write constraints in order to find security vulnerabilities in a system.

This thesis evaluates Scoria on three systems (sizes …


Effective Auto Encoder For Unsupervised Sparse Representation, Faria Mahnaz Jan 2015

Effective Auto Encoder For Unsupervised Sparse Representation, Faria Mahnaz

Wayne State University Theses

High dimensionality and the sheer size of unlabeled data available today demand

new development in unsupervised learning of sparse representation. Despite of recent

advances in representation learning, most of the current methods are limited when

dealing with large scale unlabeled data. In this study, we propose a new unsupervised

method that is able to learn sparse representation from unlabeled data efficiently. We

derive a closed-form solution based on the sequential minimal optimization (SMO)

for training an auto encoder-decoder module, which efficiently extracts sparse and

compact features from any data set with various size. The inference process in the

proposed learning …


Quantitative And Qualitative Evaluation Of Metrics On Object Graphs Extracted By Abstract Interpretation, Sumukhi Chandrashekar Jan 2015

Quantitative And Qualitative Evaluation Of Metrics On Object Graphs Extracted By Abstract Interpretation, Sumukhi Chandrashekar

Wayne State University Theses

Evaluating programming-language based techniques is crucial to judge their usefulness in practice but requires a careful selection of systems on

which to evaluate the technique. Since it is particularly hard to evaluate a heavyweight technique, such as one that requires adding annotations

to the code or rewriting the system in a radically different language, it is common to use a lightweight proxy to predict the technique's usefulness

for a system. But the reliability of such a proxy is unclear.

We propose a principled data-driven approach to derive a lightweight proxy for a heavyweight technique that requires adding annotations to the …


Bayesian Approach For Early Stage Event Prediction In Survival Data, Mahtab Jahanbani Fard Jan 2015

Bayesian Approach For Early Stage Event Prediction In Survival Data, Mahtab Jahanbani Fard

Wayne State University Theses

Predicting event occurrence at an early stage in longitudinal studies is an important and challenging problem which has high practical value. As opposed to the standard classification and regression problems where a domain expert can provide the labels for the data in a reasonably short period of time, training data in such longitudinal studies must be obtained only by waiting for the occurrence of sufficient number of events. On the other hand, survival analysis aims at finding the underlying distribution for data that measure the length of time until the occurrence of an event. However, it cannot give an answer …


Survival Analysis Approach For Early Prediction Of Student Dropout, Sattar Ameri Jan 2015

Survival Analysis Approach For Early Prediction Of Student Dropout, Sattar Ameri

Wayne State University Theses

Retention of students at colleges and universities has long been a concern for educators for many decades. The consequences of student attrition are significant for both students, academic staffs and the overall institution. Thus, increasing student retention is a long term goal of any academic institution. The most vulnerable students at all institutions of higher education are the freshman students, who are at the highest risk of dropping out at the beginning of their study. Consequently, the early identification of at-risk students is a crucial task that needs to be addressed precisely. In this thesis, we develop a framework for …