Computer Sciences Commons^™

How Ideas Grow: Critical Mass In The Linear Threshold Model, Hossein Alidaee

Mathematics, Statistics, and Computer Science Honors Projects

We study how ideas spread through a social network using the Linear Threshold Model. Each node i on the complete graph K_n is given a threshold Ɵ_i chosen uniformly at random from (0, 1]. This threshold indicates the fraction of the social network that must be active (or believe the idea) prior to node i becoming active. We start with an activated group of early adopters, called the seed set. Considering various scenarios, we use the probabilistic method to find lower bounds on size of a seed set which guarantees that all nodes become active with high …

Anomalies In Sensor Network Deployments: Analysis, Modeling, And Detection, Giovani Rimon Abuaitah

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A sensor network serves as a vital source for collecting raw sensory data. Sensor data are later processed, analyzed, visualized, and reasoned over with the help of several decision making tools. A decision making process can be disastrously misled by a small portion of anomalous sensor readings. Therefore, there has been a vast demand for mechanisms that identify and then eliminate such anomalies in order to ensure the quality, integrity, and/or trustworthiness of the raw sensory data before they can even be interpreted.

Prior to identifying anomalies, it is essential to understand the various anomalous behaviors prevalent in a sensor …

Cooperative Interactive Distributed Guidance On Mobile Devices, Gregory Burnett

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Mobiles device are quickly becoming an indispensable part of our society. Equipped with numerous communication capabilities, they are increasingly being examined as potential tools for civilian and military usage to aide in distributed remote collaboration for dynamic decision making and physical task completion. With an ever growing mobile workforce, the need for remote assistance in aiding field workers who are confronted with situations outside their expertise certainly increases. Enhanced capabilities in using mobile devices could significantly improve numerous components of a task's completion (i.e. accuracy, timing, etc.). This dissertation considers the design of mobile implementation of technology and communication capabilities …

Natural Language Document And Event Association Using Stochastic Petri Net Modeling, Michael Thomas Mills

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The purpose of this research is to design and implement a new methodology that captures the natural language understanding of events from English natural language text and model it using Stochastic Petri Nets. To establish a baseline of recent natural language processing (NLP) and understanding (NLU) research, two surveys are presented. One is a general survey in NLP and NLU methodologies for processing multi-documents. It summarizes and presents methodologies in terms of their features, capabilities, and maturity. The second survey focuses on graph-based methods for NL text processing and understanding and analyzes them in terms of their functional descriptions, capabilities …

Semsos : An Architecture For Query, Insertion, And Discovery For Semantic Sensor Networks, Joshua Kenneth Pschorr

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With sensors, storage, and bandwidth becoming ever cheaper, there has been a drive recently to make sensor data accessible on the Web. However, because of the vast number of sensors collecting data about our environment, finding relevant sensors on the Web and then interpreting their observations is a non-trivial challenge. The Open Geospatial Consortium (OGC) defines a web service specification known as the Sensor Observation Service (SOS) that is designed to standardize the way sensors and sensor data are discovered and accessed on the Web. Though this standard goes a long way in providing interoperability between sensor data producers and …

Two Fundamental Building Blocks To Provide Quick Reaction Capabilities For The Department Of Defense, Daniel Alan Uppenkamp

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The Department of Defense (DoD) has a need for long-term development efforts in conjunction with short-term development efforts. Ideally, Quick Reaction Capabilities (QRC) would be able to make use of the same processes that are used for Acquisition Programs (AP) with a few modifications to accommodate the accelerated schedule. Unfortunately, APs have a more fundamental problem with both the development process and the development framework. In August of 2007, the agile development process and modular, open source framework discussed in this thesis were two key factors that enabled the Air Force Research Laboratory (AFRL) to successfully deploy AngelFire in support …

Adaptive Semantic Annotation Of Entity And Concept Mentions In Text, Pablo N. Mendes

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The recent years have seen an increase in interest for knowledge repositories that are useful across applications, in contrast to the creation of ad hoc or application-specific databases.

These knowledge repositories figure as a central provider of unambiguous identifiers and semantic relationships between entities. As such, these shared entity descriptions serve as a common vocabulary to exchange and organize information in different formats and for different purposes. Therefore, there has been remarkable interest in systems that are able to automatically tag textual documents with identifiers from shared knowledge repositories so that the content in those documents is described in a …

Mining Diversified Decision Trees Across Multiple Datasets To Capture Similarities And Alignable Differences, Qian Han

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This dissertation studies the problem of mining shared and alignable difference knowledge structures across multiple datasets/applications. Shared and alignable difference knowledge structures are important for identifying analogies between application domains and for forming new hypothesis in challenging research applications, and for assessing the degree and types of knowledge-level similarities and differences between application domains for use in learning transfer. Generally speaking, shared knowledge structures characterize underlying datasets and highlight conceptual-level structural similarities among the datasets. This dissertation studies the mining of shared decision trees, which are a special type of shared knowledge structures. We first consider building one shared decision …

Theoretical Methods For Blur-Correction In Electron And Soft X-Ray Microscopy, Joanna Klukowska

Dissertations, Theses, and Capstone Projects

The process of object reconstruction from projections is widely used in many fields. One of the applications is the reconstruction of biological specimens from two-dimensional projections in transmission electron microscopy and transmission x-ray microscopy. Various methods have been developed for correcting the blurring that occurs when the projections are obtained by a real instrument. As the attainable resolution increases, new issues become apparent and need to be taken into account in the imaging model. In this dissertation we concentrate on the point spread function and its impact on the quality and usefulness of the reconstructions from images obtained according to …

Multimedia Recommendation: Technology And Techniques, Jialie Shen, Meng Wang, Shuicheng Yan, Peng Cui

Research Collection School Of Computing and Information Systems

In recent years, we have witnessed a rapid growth in the availability of digital multimedia on various application platforms and domains. Consequently, the problem of information overload has become more and more serious. In order to tackle the challenge, various multimedia recommendation technologies have been developed by different research communities (e.g., multimedia systems, information retrieval, machine learning and computer version). Meanwhile, many commercial web systems (e.g., Flick, YouTube, and Last.fm) have successfully applied recommendation techniques to provide users personalized content and services in a convenient and flexible way. When looking back, the information retrieval (IR) community has a long history …

Hypergraph Index: An Index For Context-Aware Nearest Neighbor Query On Social Networks, Yazhe Wang, Baihua Zheng

Research Collection School Of Computing and Information Systems

Social network has been touted as the No. 2 innovation in a recent IEEE Spectrum Special Report on “Top 11 Technologies of the Decade”, and it has cemented its status as a bona fide Internet phenomenon. With more and more people starting using social networks to share ideas, activities, events, and interests with other members within the network, social networks contain a huge amount of content. However, it might not be easy to navigate social networks to find specific information. In this paper, we define a new type of queries, namely context-aware nearest neighbor (CANN) search over social network to …

Guardian: Hypervisor As Security Foothold For Personal Computers, Yueqiang Cheng, Xuhua Ding

Research Collection School Of Computing and Information Systems

Personal computers lack of a security foothold to allow the end-users to protect their systems or to mitigate the damage. Existing candidates either rely on a large Trusted Computing Base (TCB) or are too costly to widely deploy for commodity use. To fill this gap, we propose a hypervisor-based security foothold, named as Guardian, for commodity personal computers. We innovate a bootup and shutdown mechanism to achieve both integrity and availability of Guardian. We also propose two security utilities based on Guardian. One is a device monitor which detects malicious manipulation on camera and network adaptors. The other is hyper-firewall …

Accountable Trapdoor Sanitizable Signatures, Junzuo Lai, Xuhua Ding, Yongdong Wu

Research Collection School Of Computing and Information Systems

Sanitizable signature (SS) allows a signer to partly delegate signing rights to a predetermined party, called sanitizer, who can later modify certain designated parts of a message originally signed by the signer and generate a new signature on the sanitized message without interacting with the signer. One of the important security requirements of sanitizable signatures is accountability, which allows the signer to prove, in case of dispute, to a third party that a message was modified by the sanitizer. Trapdoor sanitizable signature (TSS) enables a signer of a message to delegate the power of sanitization to any parties at anytime …

Valuation Of Participation In Social Gaming, Kwansoo Kim, Byungjoon Yoo, Robert J. Kauffman

Research Collection School Of Computing and Information Systems

This study examines the value of the time that a user spends to participate in a social game. We focus on how a massive multiplayer online role-playing game (MMORPG) vendor can establish prices to encourage participation and retain its players. We estimate value through an application of the hedonic pricing model and analyze a data set for an MMORPG in Korea. The results permit us to estimate the value of game-playing time in monetary terms. Based on our empirical results, we propose an economic model and conduct numerical simulation to show how a game vendor can apply differential pricing in …

Seller Diversity On A Technology-Based Platform, Ruhai Wu, Mei Lin

Research Collection School Of Computing and Information Systems

Managing a technology portfolio is one of the great challenges for sustained success, especially in high-technology industrieswhere technologies can be a major selling point. For engineers, this portfolio is more of a toolbox for solving design problems,but in large organizations there can be so many technologies used in different business areas that even the engineers may not beaware of all of them. When the same technologies are used in different types of products, knowledge about them can also begenerated by various groups within an organization. To improve the usefulness of a company's technology base, this paperproposes the use of a …

Special Issue: M&S Optimization Applications In Industry And Engineering, Part 2, Rafael Diaz, Andreas Tolk

VMASC Publications

(First paragraph) Welcome to the second part of the special issue on modeling and simulation (M&S) optimization applications in industry and engineering. This issue incorporates additional publications that reflect various applications and areas of simulation and optimization.

Walkcompass: Finding Walking Direction Leveraging Smartphone's Inertial Sensors, Nirupam Roy

Theses and Dissertations

Determining moving direction with smartphone's inertial sensors is a well known problem in the field of location service. Compass alone cannot solve this problem because smartphone's compass cannot achieve high accuracy. Moreover GPS is not suitable in indoor scenario. Another well known approach is dead-reckoning but dead-reckoning needs to know phones initial orientation and over time it keeps accumulating errors and after some time the estimation becomes to noisy to use. To overcome these limitations, we propose a solution called WalkCompass which is specially designed for pedestrians keeping in mind the variation of force during normal human walk. Therefore the …

Human Performance Regression Testing, Amanda Swearngin, Myra B. Cohen, Bonnie E. John, Rachel K. E. Bellamy

School of Computing: Conference and Workshop Papers

As software systems evolve, new interface features such as keyboard shortcuts and toolbars are introduced. While it is common to regression test the new features for functional correctness, there has been less focus on systematic regression testing for usability, due to the effort and time involved in human studies. Cognitive modeling tools such as CogTool provide some help by computing predictions of user performance, but they still require manual effort to describe the user interface and tasks, limiting regression testing efforts. In recent work, we developed CogTool-Helper to reduce the effort required to generate human performance models of existing systems. …

Fea Estimation And Experimental Validation Of Solid Rotor And Magnet Eddy Current Loss In Single-Sided Axial Flux Permanent Magnet Machines, Xu Yang, Dean Patterson, Jerry Hudgins, Jessica Colton

Department of Electrical and Computer Engineering: Faculty Publications

The rotor and magnet loss in single-sided axial flux permanent magnet machines with non-overlapped windings is studied in this paper. FEA estimations of the loss are carried out using both 2-D and 3-D modeling. The rotor and magnet losses are determined separately for stator slot passing and MMF space harmonics from currents in the stator. The segregation of loss between the solid rotor plate and the magnet is addressed. The eddy current loss reduction by magnet segments is discussed as well. The prototype 24 slot/22 pole single-sided AFPMs, fabricated with both single layer and double layer windings are assembled. Methods …

Concept Drift Datasets, Patrick Lindstrom

Doctoral

This zip file contains the datasets used in the PhD thesis:

Lindstrom, P., 2013. Handling Concept Drift in the Context of Expensive Labels. Technological University Dublin. For more information about the datasets please see the README file and the aforementioned thesis.

Towards Next-Generation Multimedia Recommendation Systems, Jialie Shen, Shuicheng Yan, Xian-Sheng Hua

Research Collection School Of Computing and Information Systems

Empowered by advances in information technology, such as social media network, digital library and mobile computing, there emerges an ever-increasing amounts of multimedia data. As the key technology to address the problem of information overload, multimedia recommendation system has been received a lot of attentions from both industry and academia. This course aims to 1) provide a series of detailed review of state-of-the-art in multimedia recommendation; 2) analyze key technical challenges in developing and evaluating next generation multimedia recommendation systems from different perspectives and 3) give some predictions about the road lies ahead of us.

Do Household Cable Tv Viewing Patterns Demonstrate Efficiency And Concentration?, Rae Chang, Pulak Ghosh, Gwangjae Jung, Robert J. Kauffman, Peiran Zhang

Research Collection School Of Computing and Information Systems

No abstract provided.

A Study Of The Imitation, Collection And Usability Issues Of Keystroke Biometrics, Chee Meng Tey

Dissertations and Theses Collection (Open Access)

The majority of authentication systems used today involves passwords, where a user is required to remember and key in the correct password to login. Keystroke biometrics is an alternative approach whereby users are identified by one or more features such as (a) the timing between keystrokes, (b) how long users hold each key and (c) how hard users press each key. It is being assumed in prior research that the way one user types a password/word is different from the way another user types the same password and this characteristic remains stable over time. Existing literature however left open three …

Exploiting Human Factors In User Authentication, Payas Gupta

Dissertations and Theses Collection (Open Access)

Our overarching issue in security is the human factor – and dealing with it is perhaps one of the biggest challenges we face today. Human factor is often described as the weakest part of a security system and users are often described as the weakest link in the security chain. In this thesis, we focus on two problems which are caused by human factors in user authentication and propose respective solutions. a) Secrecy information inference attack – publicly available information can be used to infer some secrecy information about the user. b) Coercion attack – where an attacker forces a …

Impact Of Multimedia In Sina Weibo, Xun Zhao

Dissertations and Theses Collection (Open Access)

Multimedia contents such as images and videos are widely used in social network sites nowadays. Sina Weibo, a Chinese microblogging service, is one of the first microblog platforms to incorporate multimedia content sharing features. This thesis provides statistical analysis on how multimedia contents are produced, consumed, and propagated in Sina Weibo. Based on 230 million tweets and 1.8 million user profiles in Sina Weibo, we study the impact of multimedia contents on the popularity of both users and tweets as well as tweet life span. In addition to consider the multimedia impact on popularity, we also compare the user influence …

Towards Secure And Usable Leakage-Resilient Password Entry, Qiang Yan

Dissertations and Theses Collection (Open Access)

Password leakage is one of the most common security threats for pervasive password based user authentication. The design of a secure and usable password entry against password leakage remains a challenge since twenty year ago when the first academic proposal attempted to address it. This dissertation focuses on investigating the difficulty in designing leakage-resilient password entry (LRPE) schemes and exploring the feasibility of constructing secure and usable LRPE schemes with the assistance of state-of-the-art technology. The first work in this dissertation reveals the infeasibility of designing practical LRPE schemes in the absence of trusted devices by investigating the inherent tradeoff …

Understanding And Rejecting Errant Touches On Multi-Touch Tablets, Ke Shu

Dissertations and Theses Collection (Open Access)

Given the pervasion of multi-touch tablet, pen-based applications have rapidly moved onto this new platform. Users draw both with bare fingers and using capacitive pens as they would do on paper in the past. Unlike paper, these tablets cannot distinguish legitimate finger/pen input from accidental touches by other parts of the user’s hand. In this thesis, we refer it to as errant touch rejection problem since users may unintentionally touch the screen with other parts of their hand. In this thesis, I design, implement and evaluate new approaches, bezel-focus rejection, of preventing errant touches on multi-touch tablets. I began the …

Employing Learning To Improve The Performance Of Meta-Raps, Fatemah Al-Duoli, Ghaith Rabadi

Engineering Management & Systems Engineering Faculty Publications

In their search for satisfactory solutions to complex combinatorial problems, metaheuristics methods are expected to intelligently explore the solution space. Various forms of memory have been used to achieve this goal and improve the performance of metaheuristics, which warranted the development of the Adaptive Memory Programming (AMP) framework [1]. This paper follows this framework by integrating Machine Learning (ML) concepts into metaheuristics as a way to guide metaheuristics while searching for solutions. The target metaheuristic method is Meta-heuristic for Randomized Priority Search (Meta-RaPS). Similar to most metaheuristics, Meta-RaPS consists of construction and improvement phases. Randomness coupled with a greedy heuristic …

A Federated Architecture For Managing Health Information In Ethiopia, Russell Gillen Ms

All Student Scholarship

Electronic health systems can be leveraged to aid in the delivery and management of health care for patients in developing countries. The delivery of health information by mobile devices is playing an increasing role in health information management.

Dynamically Adjusting Game-Play In 2d Platformers Using Procedural Level Generation, Daniel Wheat

Theses : Honours

The rapid growth of the entertainment industry has presented the requirement for more efficient development of computerized games. Importantly, the diversity of audiences that participate in playing games has called for the development of new technologies that allow games to address users with differing levels of skills and preferences. This research presents a systematic study that explored the concept of dynamic difficulty using procedural level generation with interactive evolutionary computation. Additionally, the design, development and trial of computerized agents the play game levels in the place of a human player is detailed. The work presented in this thesis provides a …