Computer Engineering Commons^™

Self‐Regulating Action Exploration In Reinforcement Learning, Teck-Hou Teng, Ah-Hwee Tan, Yuan-Sin Tan

Research Collection School Of Computing and Information Systems

The basic tenet of a learning process is for an agent to learn for only as much and as long as it is necessary. With reinforcement learning, the learning process is divided between exploration and exploitation. Given the complexity of the problem domain and the randomness of the learning process, the exact duration of the reinforcement learning process can never be known with certainty. Using an inaccurate number of training iterations leads either to the non-convergence or the over-training of the learning agent. This work addresses such issues by proposing a technique to self-regulate the exploration rate and training duration …

Linked Open Data Alignment & Querying, Prateek Jain

Browse all Theses and Dissertations

The recent emergence of the "Linked Data" approach for publishing data represents a major step forward in realizing the original vision of a web that can "understand and satisfy the requests of people and machines to use the web content" i.e. the Semantic Web. This new approach has resulted in the Linked Open Data (LOD) Cloud, which includes more than 295 large datasets contributed by experts belonging to diverse communities such as geography, entertainment, and life sciences. However, the current interlinks between datasets in the LOD Cloud, as we will illustrate,are too shallow to realize much of the benefits promised. …

Optimization Of Spectrum Allocation In Cognitive Radio And Dynamic Spectrum Access Networks, Tao Zhang

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Spectrum has become a treasured commodity. However, many licensed frequency bands exclusively assigned to the primary license holders (also called primary users) remain relatively unused or under-utilized for most of the time. Allowing other users (also called secondary users) without a license to operate in these bands with no interference becomes a promising way to satisfy the fast growing needs for frequency spectrum resources. A cognitive radio adapts to the environment it operates in by sensing the spectrum and quickly decides on appropriate frequency bands and transmission parameters to use in order to achieve certain performance goals. One of the …

Abstraction Driven Application And Data Portability In Cloud Computing, Ajith Harshana Ranabahu

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Cloud computing has changed the way organizations create, manage, and evolve their applications. While many organizations are eager to use the cloud, tempted by substantial cost savings and convenience, the implications of using clouds are still not well understood. One of the major concerns in cloud adoption is the vendor lock-in of applications, caused by the heterogeneity of the numerous cloud service offerings. Vendor locked applications are difficult, if not impossible to port from one cloud system to another, forcing cloud service consumers to use undesired or suboptimal solutions. This dissertation investigates a complete and comprehensive solution to address the …

Winding Resistance And Winding Power Loss Of High-Frequency Power Inductors, Rafal P. Wojda

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The scope of this research is concentrated on analytical winding size optimization (thickness or diameter) of high-frequency power inductors wound with foil, solid-round wire, multi-strand wire, and litz-wire conductors.

The first part of this research concerns analytical optimization of the winding size (thickness or diameter) for the inductors conducting a sinusoidal current. Estimation of winding resistance in individual inductor layers made of foil, taking into account the skin and proximity effects is performed. Approximated equations for the winding power loss in each layer are given and the optimal values of foil thickness for each layer are derived.

A low- and …

Cloudvista: A Framework For Interactive Visual Cluster Exploration Of Big Data In The Cloud, Zhen Li

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With the development and deployment of ubiquitous information sensing, mobile devices,wireless sensor networks, RFID readers, simulation, and computer generated software logs, big data have become precious resources for scientific study, business intelligence, and national security. As one of the most intuitive and effective analysis methods,visual cluster analysis remains as a significant challenge for big datasets. First, existing visualization models need to be updated to process big data in parallel. Second, processing big data inevitably bring large latency, which conflicts the requirement of interactivity. In this thesis, we develop the CloudVista framework to address the common problems with data reduction methods …

Knowledge Acquisition In A System, Christopher J. Thomas

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I present a method for growing the amount of knowledge available on the Web using a hermeneutic method that involves background knowledge, Information Extraction techniques and validation through discourse and use of the extracted information.

I present the metaphor of the "Circle of Knowledge on the Web". In this context, knowledge acquisition on the web is seen as analogous to the way scientific disciplines gradually increase the knowledge available in their field.

Here, formal models of interest domains are created automatically or manually and then validated by implicit and explicit validation methods before the statements in the created models can …

Effects Of Visual Interaction Methods On Simulated Unmanned Aircraft Operator Situational Awareness, Brent A. Terwilliger

Publications

The limited field of view of static egocentric visual displays employed in unmanned aircraft controls introduces the soda straw effect on operators, which significantly affects their ability to capture and maintain situational awareness by not depicting peripheral visual data. The problem with insufficient operator situational awareness is the resulting increased potential for error and oversight during operation of unmanned aircraft, leading to accidents and mishaps costing United States taxpayers between $4 million to $54 million per year. The purpose of this quantitative experimental completely randomized design study was to examine and compare use of dynamic eyepoint to static visual interaction …

Video Mosaicing Using Inertial Sensors, Arturo Maya Pereyra

Open Access Theses & Dissertations

A method to reduce the process complexity of Video Mosaicing could rely on information concerning the orientation of the camera instead of image feature tracking. Inertial sensors (e.g. accelerometers and gyros) could form part of a low cost motion based technology which can be used in this case and this thesis details an approach for Video Mosaicing based on such technology that requires non-computationally intensive algorithms.

Erasure Techniques In Mrd Codes, Florentin Smarandache, W.B. Vasantha Kandasamy, R. Sujatha, R.S. Raja Durai

Branch Mathematics and Statistics Faculty and Staff Publications

In this book the authors study the erasure techniques in concatenated Maximum Rank Distance (MRD) codes. The authors for the first time in this book introduce the new notion of concatenation of MRD codes with binary codes, where we take the outer code as the RD code and the binary code as the inner code. The concatenated code consists of the codewords of the outer code expressed in terms of the alphabets of the inner code. These new class of codes are defined as CRM codes. This concatenation techniques helps one to construct any CRM code of desired minimum distance …

Preface: Trends In Natural And Machine Intelligence, Jonathan H. Chan, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

Trends in natural and machine intelligence are increasingly reflecting a convergence in these two well-established fields of study. The Third International Neural Network Society Winter Conference (INNS-WC 2012) was held in Bangkok, Thailand, on October 3-5, 2012. INNS-WC2012, with an aim to bring together scientists, practitioners, and students worldwide, to discuss the past, present, and future challenges and trends in the area of natural and machine intelligence. This event has been a bi-annual conference of the International Neural Network Society (INNS) to provide a forum for international researchers to exchange latest ideas and advances on neural networks and related discipline.

An Improved Medium Access Control Protocol For Real-Time Applications In Wlans And Its Firmware Development, Sushil Dutt

Theses: Doctorates and Masters

The IEEE 802.11 Wireless Local Area Network (WLAN), commonly known as Wi-Fi, has emerged as a popular internet access technology and researchers are continuously working on improvement of the quality of service (QoS) in WLAN by proposing new and efficient schemes. Voice and video over Internet Protocol (VVoIP) applications are becoming very popular in Wi-Fi enabled portable/handheld devices because of recent technological advancements and lower service costs. Different from normal voice and video streaming, these applications demand symmetric throughput for the upstream and downstream. Existing Wi-Fi standards are optimised for generic internet applications and fail to provide symmetric throughput due …

Enhancing Spectrum Utilization In Dynamic Cognitive Radio Systems, Dusadee Treeumnuk

Electrical & Computer Engineering Theses & Dissertations

Cognitive radio (CR) is regarded as a viable solution to enabling flexible use of the frequency spectrum in future generations of wireless systems by allowing unlicensed secondary users (SU) to access licensed spectrum under the specific condition that no harmful interference be caused to the licensed primary users (PU) of the spectrum. In practical scenarios, the knowledge of PU activity is unknown to CRs and radio environments are mostly imperfect due to various issues such as noise uncertainty and multipath fadings. Therefore, important functionalities of CR systems are to efficiently detect availability of radio spectrum as well as to avoid …

A Comparison Of Near-Infrared And Visible Imaging For Surveillance Applications, Kathryn Nicole Rodhouse

Masters Theses

"A computer vision approach is investigated which has low computational complexity and which compares near-infrared and visible image systems. The target application is a surveillance system for pedestrian and vehicular traffic. Near-infrared light has potential benefits including non-visible illumination requirements. Image-processing and intelligent classification algorithms for monitoring pedestrians are implemented in outdoor and indoor environments with frequent traffic. The image set collected consists of persons walking in the presence of foreground as well as background objects at different times during the day. Image sets with nonperson objects, e.g. bicycles and vehicles, are also considered. The complex, cluttered environments are highly …

Identification Of Influential Social Networkers, Magdalini Eirinaki, S. P. Singh Monga, S. Sundaram

Magdalini Eirinaki

Online social networking is deeply interleaved in today's lifestyle. People come together and build communities to share thoughts, offer suggestions, exchange information, ideas, and opinions. Moreover, social networks often serve as platforms for information dissemination and product placement or promotion through viral marketing. The success rate in this type of marketing could be increased by targeting specific individuals, called 'influential users', having the largest possible reach within an online community. In this paper, we present a method aiming at identifying the influential users within an online social networking application. We introduce ProfileRank, a metric that uses popularity and activity characteristics …

Null Convention Logic Applications Of Asynchronous Design In Nanotechnology And Cryptographic Security, Jun Wu

Doctoral Dissertations

"This dissertation presents two Null Convention Logic (NCL) applications of asynchronous logic circuit design in nanotechnology and cryptographic security. The first application is the Asynchronous Nanowire Reconfigurable Crossbar Architecture (ANRCA); the second one is an asynchronous S-Box design for cryptographic system against Side-Channel Attacks (SCA). The following are the contributions of the first application: 1) Proposed a diode- and resistor-based ANRCA (DR-ANRCA). Three configurable logic block (CLB) structures were designed to efficiently reconfigure a given DR-PGMB as one of the 27 arbitrary NCL threshold gates. A hierarchical architecture was also proposed to implement the higher level logic that requires a …

Speech Intelligibility Prediction Using A Neurogram Similarity Index Measure, Andrew Hines, Naomi Harte

Articles

Performance Intensity functions can be used to provide additional information over measurement of speech reception threshold and maximum phoneme recognition by plotting a test subject's recognition probability over a range of sound intensities. A computational model of the auditory periphery was used to replace the human subject and develop a methodology that simulates a real listener test. The newly developed NSIM is used to evaluate the model outputs in response to Consonant-Vowel-Consonant (CVC) word lists and produce phoneme discrimination scores.

Survivable Smart Grid Communication: Smart-Meters Meshes To The Rescue, Arjun Athreya, Patrick Tague

Patrick Tague

Smart grids are critical cyber-physical infrastructures in the world now. Since these infrastructures are prone to large scale outages due to disasters or faults, a resilient and survivable communication architecture is desired. In this work, we propose a resilient and survivable hierarchical communication architecture for the smart grid that mirrors the hierarchy of the existing power grid. Post-disaster resilience in grid communication is achieved through the grid flattening process. This process involves smart-meters and other disaster surviving elements of higher system levels of the grid forming a wireless mesh network. The flattened network of grid elements with one-hop communication links …

Perfil Formativo Generado En Los Entornos Cscl: Un Estudio De Caso, Ivan Jorrín Abellán

Ivan M. Jorrín Abellán

En este trabajo se presenta el "Perfil Formativo aplicable a espacios de enseñanza-aprendizaje CSCL (Computer Supported Collaborative Learning)" que ha emergido del estudio profundo de la asignatura de Arquitectura de Ordenadores de 4º Curso de la titulación de Ingeniería en Telecomunicación en la Universidad de Valladolid durante cuatro cursos académicos. Esta tesis doctoral plantea un conjunto de recomendaciones prácticas experienciales que los practicantes de este tipo de ambientes colaborativos pueden aplicar a sus procesos de diseño y puesta en práctica de espacios CSCL. Del estudio de caso analizado emergen también una propuesta de esquema de diseño de espacios CSCL, y …

Solving Problems Of Virus Definition Files - A Triz Perspective, Umakant Mishra

Umakant Mishra

Signature scanning is the most popular method of virus scanning and is adopted by all anti-virus programs. Signature scanning is capable of detecting more than 80% of viruses. It uses a simple logic and uses less memory and system resources. Although it has a lot of advantages, it has one big disadvantage. It requires the virus signature to be extracted by the experts and stored in a database called “virus signature database”. This virus signature database has to be updated by the anti-virus developers and the end users periodically in order to deal with the latest viruses.

A typical virus …

User Experience In Service Design: Defining A Common Ground From Different Fields, Karim Touloum, Djilali Idoughi, Ahmed Seffah

Professor Djilali IDOUGHI

The emerging field of service design combines several methods mainly from the fields of product, software and interaction design, for designing the experience and interface to services. However, User eXperience design is not easy to understand because it is a new approach and covers many different fields (usability, psychology, marketing…). More often the design team members come from various domains with different cultural backgrounds such as engineers and marketing. Therefore, it is necessary to have a common definition to share the same understanding of this concept. In this paper, we investigate the main definitions proposed in the literature and the …

On The Connectivity Of Wireless Networks With Multiple Directional Antennas, Hong-Ning Dai

Hong-Ning Dai

The network connectivity is one of important measures of the performance of wireless networks. However, most of current studies on the network connectivity only consider either an SOMN network, where each node is mounted with a single omni-directional antenna, or an SDA network, where each node is mounted with a single directional antenna. Using multiple directional antennas instead of a single directional antenna can potentially improve the network performance. In this paper, we investigate the connectivity of a novel network, in terms of an MDA network, where each node is mounted with multiple directional antennas. We found that MDA networks …

Stack Protection Mechanisms In Packet Processing Systems, Peng Wu

Peng Wu

As the functionality that current computer network can provide is becoming complicated, a traditional router with application-specific integrated circuit (ASIC) implementation can't satisfy the flexibility requirements. Instead, a programmable packet forward system based on a general-purpose processor could provide the flexibility. While this system provides flexibility, a new potential security issue arises. Usually, software is involved as the packet forward system is programmable. The software's potential vulnerability, especially as to the remote exploits, becomes an issue of network security. In this thesis work, we proposed a software stack overflow vulnerability on click modular router and show how a disastrous denial-of-service …

A Business Model Perspective For Icts In Public Engagement, Mutaz M. Al-Debei, Panagiotis Panagiotopoulos, Guy Fitzgerald, Tony Elliman

Dr. Mutaz M. Al-Debei

Public institutions, in their efforts to promote meaningful citizen engagement, are increasingly looking at the democratic potential of Information and Communication Technologies (ICTs). Previous studies suggest that such initiatives seem to be impeded by socio-technical integration barriers such as low sustainability, poor citizen acceptance, coordination difficulties, lack of understanding and failure to assess their impact. Motivated by these shortcomings, the paper develops and applies a business model perspective as an interceding framework foranalysisandevaluation. The underlying principlebehind thisapproachisthatit isnottechnology per se which determines success, but rather the way in which the business model of the technological artifact is configured and employed …