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Articles 7231 - 7260 of 9003

Full-Text Articles in Computer Sciences

Effects Of Appearance And Functions On Likability And Perceived Occupational Suitability Of Robots, Sau-Lai Lee, Ivy Yee-Man Lau, Ying-Yi Hong Jun 2011

Effects Of Appearance And Functions On Likability And Perceived Occupational Suitability Of Robots, Sau-Lai Lee, Ivy Yee-Man Lau, Ying-Yi Hong

Research Collection School of Social Sciences

This article reports three experiments that examined the association between (a) appearances and perceived capabilities of robots, (b) appearance and capabilities of robots and liking for the robots, and (c) perceived capabilities of robots and judgments concerning their suitability for different occupations. In Experiment 1, the authors found that participants perceived human- and animal-like robots to have relatively more warmth-related (e.g., emotion) capabilities than machinelike robots have. In Experiment 2, the authors found that liking for robots was not affected by their human likeness or their having warmth or competence capabilities. In Experiment 3, participants generally thought that robots should …


Online Fault Detection Of Induction Motors Using Frequency Domain Independent Components Analysis, Zhaoxia Wang, C. S. Chang Jun 2011

Online Fault Detection Of Induction Motors Using Frequency Domain Independent Components Analysis, Zhaoxia Wang, C. S. Chang

Research Collection School Of Computing and Information Systems

This paper proposes an online fault detection method for induction motors using frequency-domain independent component analysis. Frequency-domain results, which are obtained by applying Fast Fourier Transform (FFT) to measured stator current time-domain waveforms, are analyzed with the aim of extracting frequency signatures of healthy and faulty motors with broken rotor-bar or bearing problem. Independent components analysis (ICA) is applied for such an aim to the FFT results. The obtained independent components as well as the FFT results are then used to obtain the combined fault signatures. The proposed method overcomes problems occurring in many existing FFT-based methods. Results using laboratory-collected …


A Feature Based Frequency Domain Analysis Algorithm For Fault Detection Of Induction Motors, Zhaoxia Wang, C. S. Chang, Zhang Yifan Jun 2011

A Feature Based Frequency Domain Analysis Algorithm For Fault Detection Of Induction Motors, Zhaoxia Wang, C. S. Chang, Zhang Yifan

Research Collection School Of Computing and Information Systems

This paper studies the stator currents collected from several inverter-fed laboratory induction motors and proposes a new feature based frequency domain analysis method for performing the detection of induction motor faults, such as the broken rotor-bar or bearing fault. The mathematical formulation is presented to calculate the features, which are called FFT-ICA features in this paper. The obtained FFT-ICA features are normalized by using healthy motor as benchmarks to establish a feature database for fault detection. Compare with conventional frequency-domain analysis method, no prior knowledge of the motor parameters or other measurements are required for calculating features. Only one phase …


Query Weighting For Ranking Model Adaptation, Peng Cai, Wei Gao, Aoying Zhou, Kam-Fai Wong Jun 2011

Query Weighting For Ranking Model Adaptation, Peng Cai, Wei Gao, Aoying Zhou, Kam-Fai Wong

Research Collection School Of Computing and Information Systems

We propose to directly measure the importance of queries in the source domain to the target domain where no rank labels of documents are available, which is referred to as query weighting. Query weighting is a key step in ranking model adaptation. As the learning object of ranking algorithms is divided by query instances, we argue that it’s more reasonable to conduct importance weighting at query level than document level. We present two query weighting schemes. The first compresses the query into a query feature vector, which aggregates all document instances in the same query, and then conducts query weighting …


Regret Minimizing Audits: A Learning-Theoretic Basis For Privacy Protection, Jeremiah Blocki, Nicolas Christin, Anupam Datta, Arunesh Sinha Jun 2011

Regret Minimizing Audits: A Learning-Theoretic Basis For Privacy Protection, Jeremiah Blocki, Nicolas Christin, Anupam Datta, Arunesh Sinha

Research Collection School Of Computing and Information Systems

Audit mechanisms are essential for privacy protection in permissive access control regimes, such as in hospitals where denying legitimate access requests can adversely affect patient care. Recognizing this need, we develop the first principled learning-theoretic foundation for audits. Our first contribution is a game-theoretic model that captures the interaction between the defender (e.g., hospital auditors) and the adversary (e.g., hospital employees). The model takes pragmatic considerations into account, in particular, the periodic nature of audits, a budget that constrains the number of actions that the defender can inspect, and a loss function that captures the economic impact of detected and …


High-Performance Composite Event Monitoring System Supporting Large Numbers Of Queries And Sources, Sangjeong Lee, Youngki Lee, Byoungjip Kim, K. Selcuk Candan, Yunseok Rhee, Junehwa Song Jun 2011

High-Performance Composite Event Monitoring System Supporting Large Numbers Of Queries And Sources, Sangjeong Lee, Youngki Lee, Byoungjip Kim, K. Selcuk Candan, Yunseok Rhee, Junehwa Song

Research Collection School Of Computing and Information Systems

This paper presents a novel data structure, called Event-centric Composable Queue (ECQ), a basic building block of a new scalable composite event monitoring (CEM) framework, SCEMon. In particular, we focus on the scalability issues when large numbers of CEM queries and event sources exist in upcoming CEM environments. To address these challenges effectively, we take an event-centric sharing approach rather than dealing with queries and sources separately. ECQ is a shared queue, which stores incoming event instances of a primitive event class. ECQs are designed to facilitate efficient shared evaluations of multiple queries over very large volumes of event streams …


Smoothly Varying Affine Stitching, Wen-Yan Lin, Siying Liu, Yasuyuki Matsuhita, Tian-Tsong Ng, Loong-Fah Cheong Jun 2011

Smoothly Varying Affine Stitching, Wen-Yan Lin, Siying Liu, Yasuyuki Matsuhita, Tian-Tsong Ng, Loong-Fah Cheong

Research Collection School Of Computing and Information Systems

Traditional image stitching using parametric transforms such as homography, only produces perceptually correct composites for planar scenes or parallax free camera motion between source frames. This limits mosaicing to source images taken from the same physical location. In this paper, we introduce a smoothly varying affine stitching field which is flexible enough to handle parallax while retaining the good extrapolation and occlusion handling properties of parametric transforms. Our algorithm which jointly estimates both the stitching field and correspondence, permits the stitching of general motion source images, provided the scenes do not contain abrupt protrusions.


Supervisory Evolutionary Optimization Strategy For Adaptive Maintenance Schedules, Zhaoxia Wang, C. S. Chang Jun 2011

Supervisory Evolutionary Optimization Strategy For Adaptive Maintenance Schedules, Zhaoxia Wang, C. S. Chang

Research Collection School Of Computing and Information Systems

No abstract provided.


Towards Human-Like Social Multi-Agents With Memetic Automaton, Liang Feng, Yew-Soon Ong, Ah-Hwee Tan, Xian-Shun Chen Jun 2011

Towards Human-Like Social Multi-Agents With Memetic Automaton, Liang Feng, Yew-Soon Ong, Ah-Hwee Tan, Xian-Shun Chen

Research Collection School Of Computing and Information Systems

Memetics is a new science that has attracted increasing attentions in the recent decades. Beyond the formalism of simple hybrids, adaptive hybrids and memetic algorithms, the notion of memetic automaton as an adaptive entity that is self-contained and uses memes as building blocks of information is recently conceptualized in the context of computational intelligence as potential tools for effective problem-solving [1]. Taking this cue, this paper embarks a study on Memetic Multiagent system (MeM) towards human-like social agents with memetic automaton. Particularly, we introduce a potentially rich meme-inspired design and operational model, with Darwin’s theory of natural selections and Dawkins’ …


Using Service Responsibility Tables To Supplement Uml In Analyzing E-Service Systems, Xin Tan, Steven Alter, Keng Siau Jun 2011

Using Service Responsibility Tables To Supplement Uml In Analyzing E-Service Systems, Xin Tan, Steven Alter, Keng Siau

Research Collection School Of Computing and Information Systems

This paper proposes using Service Responsibility Tables (SRTs) as a tool in analyzing e-service systems. First it discusses difficulties and deficiencies of using formal modeling languages such as UML in analyzing e-service systems. It proposes using SRTs as an informal language and lightweight analytical tool to be used by business professionals in analyzing e-service systems. SRTs are based on a service value chain framework but do not rely on abstract concepts and constructs, and therefore can be used by business professionals to supplement UML. We suggest a set of heuristics for transforming SRTs into two key UML diagrams, thereby illustrating …


Adaptive Display Power Management For Mobile Games, Bhojan Anand, Karthik Thirugnanam, Jeena Sebastian, Pravein G. Kannan, Akhihebbal L. Ananda, Mun Choon Chan, Rajesh Krishna Balan Jun 2011

Adaptive Display Power Management For Mobile Games, Bhojan Anand, Karthik Thirugnanam, Jeena Sebastian, Pravein G. Kannan, Akhihebbal L. Ananda, Mun Choon Chan, Rajesh Krishna Balan

Research Collection School Of Computing and Information Systems

In this paper, we show how tone mapping techniques can be used to dynamically increase the image brightness, thus allowing the LCD backlight levels to be reduced. This saves significant power as the majority of the LCD’s display power is consumed by its backlight. The Gamma function (or equivalent) can be efficiently implemented in smartphones with minimal resource cost. We describe how we overcame the Gamma function’s non-linear nature by using adaptive thresholds to apply different Gamma values to images with differing brightness levels. These adaptive thresholds allow us to save significant amounts of power while preserving the image quality. …


Getting To Global Yes! Designing A Distributed Student Collaboration, Selma Limam Mansar, Randy Weinberg, Benjamin Kok Siew Gan Jun 2011

Getting To Global Yes! Designing A Distributed Student Collaboration, Selma Limam Mansar, Randy Weinberg, Benjamin Kok Siew Gan

Research Collection School Of Computing and Information Systems

The authors have taught a course called 'Global Project Management' for four years, engaging students in three international locations in hands-on distance projects. The distance projects are intended to provide students with enriching, realistic global project experience. With experience, improved planning and better coordination, each iteration of the distance projects has improved. In this paper, the authors present lessons learned and a mind map demonstrating key aspects of design of global hands-on projects.


Fully Secure Cipertext-Policy Hiding Cp-Abe, Junzuo Lai, Robert H. Deng, Yingjiu Li Jun 2011

Fully Secure Cipertext-Policy Hiding Cp-Abe, Junzuo Lai, Robert H. Deng, Yingjiu Li

Research Collection School Of Computing and Information Systems

In ciphertext-policy attributed-based encryption (CP-ABE), each ciphertext is labeled by the encryptor with an access structure (also called ciphertext policy) and each private key is associated with a set of attributes. A user should be able to decrypt a ciphertext if and only if his private key attributes satisfy the access structure.The traditional security property of CP-ABE is plaintext privacy, which ciphertexts reveal no information about the underlying plaintext. At ACNS’08, Nishide, Yoneyama and Ohta introduced the notion of ciphertext-policy hiding CP-ABE. In addition to protecting the privacy of plaintexts, ciphertext-policy hiding CP-ABE also protects the description of the access …


Hierarchical Identity-Based Chameleon Hash And Its Applications, Feng Bao, Robert H. Deng, Xuhua Ding, Junzuo Lai, Yunlei Zhao Jun 2011

Hierarchical Identity-Based Chameleon Hash And Its Applications, Feng Bao, Robert H. Deng, Xuhua Ding, Junzuo Lai, Yunlei Zhao

Research Collection School Of Computing and Information Systems

At ACNS 2008, Canard et al. introduced the notion of trapdoor sanitizable signature (TSS) based on identity-based chameleon hash (IBCH). Trapdoor sanitizable signatures allow the signer of a message to delegate, at any time, the power of sanitization to possibly several entities who can modify predetermined parts of the message and generate a new signature on the sanitized message without interacting with the original signer. In this paper, we introduce the notion of hierarchical identity-based chameleon hash (HIBCH), which is a hierarchical extension of IBCH. We show that HIBCH can be used to construct other cryptographic primitives, including hierarchical trapdoor …


A Quality Metric For Sustainable Innovations, Arcot Desai Narasimhalu Jun 2011

A Quality Metric For Sustainable Innovations, Arcot Desai Narasimhalu

Research Collection School Of Computing and Information Systems

Sustainability has become a major concern for nations and firms especially since the Kyoto Protocol was defined in 1997. While there have been several studies on benchmarks for national innovation systems and effectiveness of innovation management within firms there is as yet no reasonable metric for determining the quality of an innovation much less its quality relating to sustainability? Similarly, there have been several studies on sustainability but that such research groups have also not focused on developing a metric for denoting the quality of sustainable innovations. This paper offers a metric that defines the quality of an innovation, especially …


Getting To Know Social Media Analytics, Tin Seong Kam May 2011

Getting To Know Social Media Analytics, Tin Seong Kam

Research Collection School Of Computing and Information Systems

Over the last five years, the unprecedented development and use of social mediating technologies such as blog, wiki, Facebook, and Tweeter have engendered radically new ways of working, playing, and creating meaning, leaving an indelible mark on nearly every domain imaginable. Despite the growing ubiquity of social mediating technologies, their potential has hardly been tapped. Effectively using data collected from social mediating technologies by the business community is far from trivial. This is mainly due to the general lack of awareness on Social Network Analysis (SNA) techniques and technologies among the business analysts and practitioners. This presentation aims to provide …


Sandcanvas: New Expressions In Sand Animation, Rubaiat Habib Kazi, Kien-Chuan Chua, Shengdong Zhao, Richard Christopher Davis, Kok-Lim Low May 2011

Sandcanvas: New Expressions In Sand Animation, Rubaiat Habib Kazi, Kien-Chuan Chua, Shengdong Zhao, Richard Christopher Davis, Kok-Lim Low

Research Collection School of Computing and Information Systems

Sand animation is a performance art technique in which an artist tells stories by creating animated images with sand. This video demonstrates the creative possibilities of SandCanvas, a new multi-touch digital artistic medium inspired by sand animation that simplifies the creation of sand animations. SandCanvas’s color and texture features enable faster, more dramatic transitions, while its mixed media and gesture recording features make it possible to create entirely new experiences. Session recording and frame capture complement these capabilities by simplifying post-production of sand animation performances.


Prototyping Video Games With Animation, Richard Christopher Davis May 2011

Prototyping Video Games With Animation, Richard Christopher Davis

Research Collection School of Computing and Information Systems

This paper outlines a proposed design for PlaySketch, a new video game storyboarding system. PlaySketch borrows ideas from the K-Sketch animation sketching system, which allows short animations to be created in minutes or seconds. We build on K-Sketch in four ways. key frame animation capabilities, a branching timeline view, microphone and web-cam support, and hooks to connect to online game design documents.


Incremental Dcop Search Algorithms For Solving Dynamic Dcop Problems, William Yeoh, Pradeep Varakantham, Xiaoxun Sun, Sven Koenig May 2011

Incremental Dcop Search Algorithms For Solving Dynamic Dcop Problems, William Yeoh, Pradeep Varakantham, Xiaoxun Sun, Sven Koenig

Research Collection School Of Computing and Information Systems

Distributed constraint optimization problems (DCOPs) are well-suited for modeling multi-agent coordination problems. However, most research has focused on developing algorithms for solving static DCOPs. In this paper, we model dynamic DCOPs as sequences of (static) DCOPs with changes from one DCOP to the next one in the sequence. We introduce the ReuseBounds procedure, which can be used by any-space ADOPT and any-space BnB-ADOPT to find cost-minimal solutions for all DCOPs in the sequence faster than by solving each DCOP individually. This procedure allows those agents that are guaranteed to remain unaffected by a change to reuse their lower and upper …


Continuous Nearest Neighbor Search In The Presence Of Obstacles, Yunjun Gao, Baihua Zheng, Gang Chen, Chun Chen, Qing Li May 2011

Continuous Nearest Neighbor Search In The Presence Of Obstacles, Yunjun Gao, Baihua Zheng, Gang Chen, Chun Chen, Qing Li

Research Collection School Of Computing and Information Systems

Despite the ubiquity of physical obstacles (e.g., buildings, hills, and blindages, etc.) in the real world, most of spatial queries ignore the obstacles. In this article, we study a novel form of continuous nearest-neighbor queries in the presence of obstacles, namely continuous obstructed nearest-neighbor (CONN) search, which considers the impact of obstacles on the distance between objects. Given a data setP, an obstacle set O, and a query line segment q, in a two-dimensional space, a CONN query retrieves the nearest neighbor p ∈ P of each point p′ on q according to the obstructed distance, the shortest path between …


Measuring Api Documentation On The Web, Chris Parnin, Christoph Treude May 2011

Measuring Api Documentation On The Web, Chris Parnin, Christoph Treude

Research Collection School Of Computing and Information Systems

Software development blogs, developer forums and Q&A websites are changing the way software is documented. With these tools, developers can create and communicate knowledge and experiences without relying on a central authority to provide official documentation. Instead, any content created by a developer is just a web search away. To understand whether documentation via social media can replace or augment more traditional forms of documentation, we study the extent to which the methods of one particular API — jQuery — are documented on the Web. We analyze 1,730 search results and show that software development blogs in particular cover 87.9% …


How Do Programmers Ask And Answer Questions On The Web? (Nier Track), Christoph Treude, Ohad Barzilay, Margaret-Anne Storey May 2011

How Do Programmers Ask And Answer Questions On The Web? (Nier Track), Christoph Treude, Ohad Barzilay, Margaret-Anne Storey

Research Collection School Of Computing and Information Systems

Question and Answer (Q&A) websites, such as Stack Overflow, use social media to facilitate knowledge exchange between programmers and fill archives with millions of entries that contribute to the body of knowledge in software development. Understanding the role of Q&A websites in the documentation landscape will enable us to make recommendations on how individuals and companies can leverage this knowledge effectively. In this paper, we analyze data from Stack Overflow to categorize the kinds of questions that are asked, and to explore which questions are answered well and which ones remain unanswered. Our preliminary findings indicate that Q&A websites are …


Second International Workshop On Web 2.0 For Software Engineering (Web2se 2011), Christoph Treude, Margaret-Anne Storey, Arie Van Deursen, Andrew Begel, Sue Black May 2011

Second International Workshop On Web 2.0 For Software Engineering (Web2se 2011), Christoph Treude, Margaret-Anne Storey, Arie Van Deursen, Andrew Begel, Sue Black

Research Collection School Of Computing and Information Systems

Social software is built around an "architecture of participation" where user data is aggregated as a side-effect of using Web 2.0 applications. Web 2.0 implies that processes and tools are socially open, and that content can be used in several different contexts. Web 2.0 tools and technologies support interactive information sharing, data interoperability and user centered design. For instance, wikis, blogs, tags and feeds help us organize, manage and categorize content in an informal and collaborative way. Some of these technologies have made their way into collaborative software development processes and development platforms. These processes and environments are just scratching …


Configuring Global Software Teams: A Multi-Company Analysis Of Productivity, Quality, And Profits, Narayanasamy Ramasubbu, Marcelo Cataldo, Rajesh Krishna Balan, James Herbsleb May 2011

Configuring Global Software Teams: A Multi-Company Analysis Of Productivity, Quality, And Profits, Narayanasamy Ramasubbu, Marcelo Cataldo, Rajesh Krishna Balan, James Herbsleb

Research Collection School Of Computing and Information Systems

In this paper, we examined the impact of project-level configurational choices of globally distributed software teams on project productivity, quality, and profits. Our analysis used data from 362 projects of four different firms. These projects spanned a wide range of programming languages, application domain, process choices, and development sites spread over 15 countries and 5 continents. Our analysis revealed fundamental tradeoffs in choosing configurational choices that are optimized for productivity, quality, and/or profits. In particular, achieving higher levels of productivity and quality require diametrically opposed configurational choices. In addition, creating imbalances in the expertise and personnel distribution of project teams …


Decentralized Decision Support For An Agent Population In Dynamic And Uncertain Domains, Pradeep Reddy Varakantham, Shih-Fen Cheng, Thi Duong Nguyen May 2011

Decentralized Decision Support For An Agent Population In Dynamic And Uncertain Domains, Pradeep Reddy Varakantham, Shih-Fen Cheng, Thi Duong Nguyen

Research Collection School Of Computing and Information Systems

This research is motivated by problems in urban transportation and labor mobility, where the agent flow is dynamic, non-deterministic and on a large scale. In such domains, even though the individual agents do not have an identity of their own and do not explicitly impact other agents, they have implicit interactions with other agents. While there has been much research in handling such implicit effects, it has primarily assumed controlled movements of agents in static environments. We address the issue of decision support for individual agents having involuntary movements in dynamic environments . For instance, in a taxi fleet serving …


Sandcanvas: A Multi-Touch Art Medium Inspired By Sand Animation, Rubaiat Habib Kazi, Kien-Chuan Chua, Shengdong Zhao, Richard Christopher Davis, Kok-Lim Low May 2011

Sandcanvas: A Multi-Touch Art Medium Inspired By Sand Animation, Rubaiat Habib Kazi, Kien-Chuan Chua, Shengdong Zhao, Richard Christopher Davis, Kok-Lim Low

Research Collection School Of Computing and Information Systems

Sand animation is a performance art technique in which an artist tells stories by creating animated images with sand. Inspired by this medium, we have developed a new multitouch digital artistic medium named SandCanvas that simplifies the creation of sand animations. SandCanvas also goes beyond traditional sand animation with tools for mixing sand animation with video and replicating recorded free-form hand gestures. In this paper, we analyze common sand animation hand gestures, present SandCanvas’s intuitive UI, and describe implementation challenges we encountered. We also present an evaluation with professional and novice artists that shows the importance and unique affordances of …


Sandcanvas: New Possibilities In Sand Animation, Rubaiat Habib Kazi, Kien-Chuan Chua, Shengdong Zhao, Richard Christopher Davis, Kok-Lim Low May 2011

Sandcanvas: New Possibilities In Sand Animation, Rubaiat Habib Kazi, Kien-Chuan Chua, Shengdong Zhao, Richard Christopher Davis, Kok-Lim Low

Research Collection School Of Computing and Information Systems

Sand animation is a performance art technique in which an artist tells stories by creating animated images with sand. This video demonstrates the creative possibilities of SandCanvas, a new multi-touch digital artistic medium inspired by sand animation that simplifies the creation of sand animations. SandCanvas’s color and texture features enable faster, more dramatic transitions, while its mixed media and gesture recording features make it possible to create entirely new experiences. Session recording and frame capture complement these capabilities by simplifying postproduction of sand animation performances.


Double Updating Online Learning, Peilin Zhao, Steven C. H. Hoi, Rong Jin May 2011

Double Updating Online Learning, Peilin Zhao, Steven C. H. Hoi, Rong Jin

Research Collection School Of Computing and Information Systems

In most kernel based online learning algorithms, when an incoming instance is misclassified, it will be added into the pool of support vectors and assigned with a weight, which often remains unchanged during the rest of the learning process. This is clearly insufficient since when a new support vector is added, we generally expect the weights of the other existing support vectors to be updated in order to reflect the influence of the added support vector. In this paper, we propose a new online learning method, termed Double Updating Online Learning, or DUOL for short, that explicitly addresses this problem. …


A Simple Curious Agent To Help People Be Curious, Han Yu, Zhiqi Shen, Chunyan Miao, Ah-Hwee Tan May 2011

A Simple Curious Agent To Help People Be Curious, Han Yu, Zhiqi Shen, Chunyan Miao, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

Curiosity is an innately rewarding state of mind that, over the millennia, has driven the human race to explore and discover. Many researches in pedagogical science have confirmed the importance of being curious to the students' cognitive development. However, in the newly popular virtual world-based learning environments (VLEs), there is currently a lack of attention being paid to enhancing the learning experience by stimulating the learners' curiosity. In this paper, we propose a simple model for curious agents (CAs) which can be used to stimulate learners' curiosity in VLEs. Potential future research directions will be discussed.


Leveraging Complex Event Processing For Smart Hospitals Using Rfid, Wen Yao, Chao-Hsien Chu, Zang Li May 2011

Leveraging Complex Event Processing For Smart Hospitals Using Rfid, Wen Yao, Chao-Hsien Chu, Zang Li

Research Collection School Of Computing and Information Systems

RFID technology has been examined in healthcare to support a variety of applications such as patient identification and monitoring, asset tracking, and patient–drug compliance. However, managing the large volume of RFID data and understanding them in the medical context present new challenges. One effective solution for dealing with these challenges is complex event processing (CEP), which can extract meaningful events for context-aware applications. In this paper, we propose a CEP framework to model surgical events and critical situations in an RFID-enabled hospital. We have implemented a prototype system with the proposed approach for surgical management and conducted performance evaluations to …