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Articles 7711 - 7740 of 9003

Full-Text Articles in Computer Sciences

Classification Of Software Behaviors For Failure Detection: A Discriminative Pattern Mining Approach, David Lo, Hong Cheng, Jiawei Han, Siau-Cheng Khoo, Chengnian Sun May 2009

Classification Of Software Behaviors For Failure Detection: A Discriminative Pattern Mining Approach, David Lo, Hong Cheng, Jiawei Han, Siau-Cheng Khoo, Chengnian Sun

Research Collection School Of Computing and Information Systems

Software is a ubiquitous component of our daily life. We often depend on the correct working of software systems. Due to the difficulty and complexity of software systems, bugs and anomalies are prevalent. Bugs have caused billions of dollars loss, in addition to privacy and security threats. In this work, we address software reliability issues by proposing a novel method to classify software behaviors based on past history or runs. With the technique, it is possible to generalize past known errors and mistakes to capture failures and anomalies. Our technique first mines a set of discriminative features capturing repetitive series …


A Self-Organizing Neural Network Architecture For Intentional Planning Agents, Budhitama Subagdja, Ah-Hwee Tan May 2009

A Self-Organizing Neural Network Architecture For Intentional Planning Agents, Budhitama Subagdja, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

This paper presents a model of neural network embodiment of intentions and planning mechanisms for autonomous agents. The model bridges the dichotomy of symbolic and non-symbolic representation in developing agents. Some novel techniques are introduced that enables the neural network to process and manipulate sequential and hierarchical structures of information. It is suggested that by incorporating intentional agent model which relies on explicit symbolic description with self-organizing neural networks that are good at learning and recognizing patterns, the best from both sides can be exploited. This paper demonstrates that plans can be represented as weighted connections and reasoning processes can …


Concernlines: A Timeline View Of Co-Occurring Concerns, Christoph Treude, Margaret-Anne Storey May 2009

Concernlines: A Timeline View Of Co-Occurring Concerns, Christoph Treude, Margaret-Anne Storey

Research Collection School Of Computing and Information Systems

Understanding the evolution of a software system requires understanding how information about the release history, non-functional requirements and project milestones relates to functional requirements on the software components. This short paper describes a new tool, called CONCERNLINES, that supports this cognitive process by visualizing co-occurring concerns over time.


A Novel Framework For Efficient Automated Singer Identification In Large Music Databases, Jialie Shen, John Shepherd, Bin Cui, Kian-Lee Tan May 2009

A Novel Framework For Efficient Automated Singer Identification In Large Music Databases, Jialie Shen, John Shepherd, Bin Cui, Kian-Lee Tan

Research Collection School Of Computing and Information Systems

Over the past decade, there has been explosive growth in the availability of multimedia data, particularly image, video, and music. Because of this, content-based music retrieval has attracted attention from the multimedia database and information retrieval communities. Content-based music retrieval requires us to be able to automatically identify particular characteristics of music data. One such characteristic, useful in a range of applications, is the identification of the singer in a musical piece. Unfortunately, existing approaches to this problem suffer from either low accuracy or poor scalability. In this article, we propose a novel scheme, called Hybrid Singer Identifier (HSI), for …


An Agent-Based Commodity Trading Simulation, Shih-Fen Cheng, Yee Pin Lim, Chao-Chi Liu May 2009

An Agent-Based Commodity Trading Simulation, Shih-Fen Cheng, Yee Pin Lim, Chao-Chi Liu

Research Collection School Of Computing and Information Systems

In recent years, the study of trading in electronic markets has received significant amount of attention, particularly in the areas of artificial intelligence and electronic commerce. With increasingly sophisticated technologies being applied in analyzing information and making decisions, fully autonomous software agents are expected to take up significant roles in many important fields. This trend is most obvious in the financial domain, where speed of reaction is highly valued and significant investments have been made in information and communication technologies.Despite the successes of automated trading in many important classes of financial markets, commodity trading has lagged behind, mainly because of …


Automatic Mining Of Functionally Equivalent Code Fragments Via Random Testing, Lingxiao Jiang, Zhendong Su May 2009

Automatic Mining Of Functionally Equivalent Code Fragments Via Random Testing, Lingxiao Jiang, Zhendong Su

Research Collection School Of Computing and Information Systems

Similar code may exist in large software projects due to some common software engineering practices, such as copying and pasting code and n-version programming. Although previous work has studied syntactic equivalence and small-scale, coarse-grained program-level and function-level semantic equivalence, it is not known whether significant fine-grained, code-level semantic duplications exist. Detecting such semantic equivalence is also desirable because it can enable many applications such as code understanding, maintenance, and optimization. In this paper, we introduce the first algorithm to automatically mine functionally equivalent code fragments of arbitrary size - down to an executable statement. Our notion of functional equivalence is …


Joint Ranking For Multilingual Web Search, Wei Gao, Cheng Niu, Ming Zhou, Kam-Fai Wong Apr 2009

Joint Ranking For Multilingual Web Search, Wei Gao, Cheng Niu, Ming Zhou, Kam-Fai Wong

Research Collection School Of Computing and Information Systems

Ranking for multilingual information retrieval (MLIR) is a task to rank documents of different languages solely based on their relevancy to the query regardless of query’s language. Existing approaches are focused on combining relevance scores of different retrieval settings, but do not learn the ranking function directly. We approach Web MLIR ranking within the learning-to-rank (L2R) framework. Besides adopting popular L2R algorithms to MLIR, a joint ranking model is created to exploit the correlations among documents, and induce the joint relevance probability for all the documents. Using this method, the relevant documents of one language can be leveraged to improve …


Exploring Hierarchically Organized Georeferenced Multimedia Annotations In The Mobitop System, Thi Nhu Quynh Kim, Khasfariyati Razikin, Dion Hoe-Lian Goh, Yin Leng Theng, Quang Minh Nguyen, Ee-Peng Lim, Aixin Sun, Chew Hung Chang, Kalyani Chatterjea Apr 2009

Exploring Hierarchically Organized Georeferenced Multimedia Annotations In The Mobitop System, Thi Nhu Quynh Kim, Khasfariyati Razikin, Dion Hoe-Lian Goh, Yin Leng Theng, Quang Minh Nguyen, Ee-Peng Lim, Aixin Sun, Chew Hung Chang, Kalyani Chatterjea

Research Collection School Of Computing and Information Systems

We introduce MobiTOP, a map-based interface for accessing hierarchically organized georeferenced annotations. Each annotation contains multimedia content associated with a location, and users are able to annotate existing annotations, in effect creating a hierarchy. MobiTOPs interface was designed using a participatory design methodology to ensure that the user interface meets the needs of potential users. A pilot study to compare the MobiTOP interface with a space-filling thumbnail (SFT) interface suggested that participants preferred the MobiTOP design for accessing annotations even though the SFT interface was conceptually easier to understand resources.


Ensuring Dual Security Modes In Rfid-Enabled Supply Chain Systems, Shaoying Cai, Tieyan Li, Yingjiu Li, Robert H. Deng Apr 2009

Ensuring Dual Security Modes In Rfid-Enabled Supply Chain Systems, Shaoying Cai, Tieyan Li, Yingjiu Li, Robert H. Deng

Research Collection School Of Computing and Information Systems

While RFID technology has greatly facilitated the supply chain management, designing a secure, visible, and efficient RFID- enabled supply chain system is still a challenge since the three equally important requirements (i.e., security, visibility, and efficiency) may conflict to each other. Few research works have been conducted to address these issues simultaneously. In this paper, we observe the different security requirements in RFID-enabled supply chain environments and differentiate the simplified model into two security levels. Accordingly, dual security modes are properly defined in our RFID setting. In the relatively secure environment, our system is set to the weak security mode, …


Efficient Mining Of Closed Repetitive Gapped Subsequences From A Sequence Database, Bolin Ding, David Lo, Jiawei Han, Siau-Cheng Khoo Apr 2009

Efficient Mining Of Closed Repetitive Gapped Subsequences From A Sequence Database, Bolin Ding, David Lo, Jiawei Han, Siau-Cheng Khoo

Research Collection School Of Computing and Information Systems

There is a huge wealth of sequence data available, for example, customer purchase histories, program execution traces, DNA, and protein sequences. Analyzing this wealth of data to mine important knowledge is certainly a worthwhile goal. In this paper, as a step forward to analyzing patterns in sequences, we introduce the problem of mining closed repetitive gapped subsequences and propose efficient solutions. Given a database of sequences where each sequence is an ordered list of events, the pattern we would like to mine is called repetitive gapped subsequence, which is a subsequence (possibly with gaps between two successive events within it) …


An Incremental Threshold Method For Continuous Text Search Queries, Kyriakos Mouratidis, Hwee Hwa Pang Apr 2009

An Incremental Threshold Method For Continuous Text Search Queries, Kyriakos Mouratidis, Hwee Hwa Pang

Research Collection School Of Computing and Information Systems

A text filtering system monitors a stream of incoming documents, to identify those that match the interest profiles of its users. The user interests are registered at a server as continuous text search queries. The server constantly maintains for each query a ranked result list, comprising the recent documents (drawn from a sliding window) with the highest similarity to the query. Such a system underlies many text monitoring applications that need to cope with heavy document traffic, such as news and email monitoring. In this paper, we propose the first solution for processing continuous text queries efficiently. Our objective is …


Efficient Evaluation Of Multiple Preference Queries, Hou U Leong, Nikos Mamaoulis, Kyriakos Mouratidis Apr 2009

Efficient Evaluation Of Multiple Preference Queries, Hou U Leong, Nikos Mamaoulis, Kyriakos Mouratidis

Research Collection School Of Computing and Information Systems

Consider multiple users searching for a hotel room, based on size, cost, distance to the beach, etc. Users may have variable preferences expressed by different weights on the attributes of the searched objects. Although individual preference queries can be evaluated by selecting the object in the database with the highest aggregate score, in the case of multiple requests at the same time, a single object cannot be assigned to more than one users. The challenge is to compute a fair 1-1 matching between the queries and a subset of the objects. We model this as a stable-marriage problem and propose …


Beyond Output Voting: Detecting Compromised Replicas Using Hmm-Based Behavioral Distance, Debin Gao, Michael K. Reiter, Dawn Song Apr 2009

Beyond Output Voting: Detecting Compromised Replicas Using Hmm-Based Behavioral Distance, Debin Gao, Michael K. Reiter, Dawn Song

Research Collection School Of Computing and Information Systems

Many host-based anomaly detection techniques have been proposed to detect code-injection attacks on servers. The vast majority, however, are susceptible to "mimicry" attacks in which the injected code masquerades as the original server software, including returning the correct service responses, while conducting its attack. "Behavioral distance," by which two diverse replicas processing the same inputs are continually monitored to detect divergence in their low-level (system-call) behaviors and hence potentially the compromise of one of them, has been proposed for detecting mimicry attacks. In this paper, we present a novel approach to behavioral distance measurement using a new type of hidden …


Describing Fuzzy Sets Using A New Concept: Fuzzify Functor, Kexin Wei, Zhaoxia Wang, Quan Wang Apr 2009

Describing Fuzzy Sets Using A New Concept: Fuzzify Functor, Kexin Wei, Zhaoxia Wang, Quan Wang

Research Collection School Of Computing and Information Systems

This paper proposed a fuzzify functor as an extension of the concept of fuzzy sets. The fuzzify functor and the first-order operated fuzzy set are defined. From the theory analysis, it can be observed that when the fuzzify functor acts on a simple crisp set, we get the first order fuzzy set or type-1 fuzzy set. By operating the fuzzify functor on fuzzy sets, we get the higher order fuzzy sets or higher type fuzzy sets and their membership functions. Using the fuzzify functor we can exactly describe the type-1 fuzzy sets, type-2 fuzzy sets and higher type or higher …


Rsa-Based Certificateless Public Key Encryption, Junzuo Lai, Robert H. Deng, Shengli Liu, Weidong Kou Apr 2009

Rsa-Based Certificateless Public Key Encryption, Junzuo Lai, Robert H. Deng, Shengli Liu, Weidong Kou

Research Collection School Of Computing and Information Systems

Certificateless Public Key Cryptography was first introduced by Al-Riyami and Paterson in order to eliminate the inherent key-escrow problem of Identity-Based Cryptography. In this paper, we present a new practical construction of certificateless public key encryption scheme without paring. Our scheme is, in the random oracle model, provably secure under the assumption that the RSA problem is intractable.


Optimal Digital Content Distribution Strategy In The Presence Of Consumer-To-Consumer Channel, Yunfang Feng, Zhiling Guo, Wei-Yu Kevin Chiang Apr 2009

Optimal Digital Content Distribution Strategy In The Presence Of Consumer-To-Consumer Channel, Yunfang Feng, Zhiling Guo, Wei-Yu Kevin Chiang

Research Collection School Of Computing and Information Systems

Although the online business-to-consumer (B2C) channel is the primary selling channel for digital content (e.g., videos, images, and music), modern digital technology has made possible the legal dissemination of such content over the consumer-to-consumer (C2C) channel through personal computing devices, such as PCs, mobile phones, and portable media players. This paper investigates the optimal channel structure and the corresponding pricing and service strategies for digital content distribution in order to understand the business value of introducing the C2C channel alongside the prevailing B2C channel. We identify conditions under which it is more profitable to use both B2C and C2C channels …


Opaque: Protecting Path Privacy In Directions Search, Ken C. K. Lee, Wang-Chien Lee, Hong Va Leong, Baihua Zheng Apr 2009

Opaque: Protecting Path Privacy In Directions Search, Ken C. K. Lee, Wang-Chien Lee, Hong Va Leong, Baihua Zheng

Research Collection School Of Computing and Information Systems

Directions search returns the shortest path from a source to a destination on a road network. However, the search interests of users may be exposed to the service providers, thus raising privacy concerns. For instance, a path query that finds a path from a resident address to a clinic may lead to a deduction about "who is related to what disease". To protect user privacy from accessing directions search services, we introduce the OPAQUE system, which consists of two major components: (1) an obfuscator that formulates obfuscated path queries by mixing true and fake sources/destinations; and (2) an obfuscated path …


Achieving Better Privacy Protection In Wireless Sensor Networks Using Trusted Computing, Yanjiang Yang, Robert H. Deng, Jianying Zhou, Ying Qiu Apr 2009

Achieving Better Privacy Protection In Wireless Sensor Networks Using Trusted Computing, Yanjiang Yang, Robert H. Deng, Jianying Zhou, Ying Qiu

Research Collection School Of Computing and Information Systems

A wireless sensor network (WSN) is an ad-hoc wireless network composed of small sensor nodes deployed in large numbers. Sensor nodes are usually severely resource limited and power constrained. Security enforcement in WSNs is thus a challenging task. In this paper we propose a clustered heterogeneous architecture for WSNs, where high-end cluster heads are incorporated, and they are further equipped with trusted computing technology (TC). As such, the cluster heads act as trusted parties, and are expected to help effectively address privacy issues in WSNs. As concrete examples, we discuss in details how user query privacy and source location privacy …


The Digital Wallet: Opportunities And Prototypes, Rajesh Krishna Balan, Narayanasamy Ramasubbu Apr 2009

The Digital Wallet: Opportunities And Prototypes, Rajesh Krishna Balan, Narayanasamy Ramasubbu

Research Collection School Of Computing and Information Systems

Example digital wallet applications support secure P2P mobile cash transactions and alleviate point-of-sale confusion for consumers using multiple payment, discount, and loyalty cards.


Optimizing Service Systems Based On Application-Level Qos, Qianhui Liang, Xindong Wu, Hoong Chuin Lau Apr 2009

Optimizing Service Systems Based On Application-Level Qos, Qianhui Liang, Xindong Wu, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

Making software systems service-oriented is becoming the practice, and an increasingly large number of service systems play important roles in today's business and industry. Currently, not enough attention has been paid to the issue of optimization of service systems. In this paper, we argue that the key elements to be considered in optimizing service systems are robustness, system orientation, and being dynamic and transparent. We present our solution to optimizing service systems based on application-level QoS management. Our solution incorporates three capabilities, i.e., 1) the ability to cater to the varying rigidities on Web service QoS in distinct application domains …


Fast Object Search On Road Networks, Ken C. K. Lee, Wang-Chien Lee, Baihua Zheng Mar 2009

Fast Object Search On Road Networks, Ken C. K. Lee, Wang-Chien Lee, Baihua Zheng

Research Collection School Of Computing and Information Systems

In this paper, we present ROAD, a general framework to evaluate Location-Dependent Spatial Queries (LDSQ)s that searches for spatial objects on road networks. By exploiting search space pruning technique and providing a dynamic object mapping mechanism, ROAD is very efficient and flexible for various types of queries, namely, range search and nearest neighbor search, on objects over large-scale networks. ROAD is named after its two components, namely, Route Overlay and Association Directory, designed to address the network traversal and object access aspects of the framework. In ROAD, a large road network is organized as a hierarchy of interconnected regional sub-networks …


Visual Word Proximity And Linguistics For Semantic Video Indexing And Near-Duplicate Retrieval, Yu-Gang Jiang, Chong-Wah Ngo Mar 2009

Visual Word Proximity And Linguistics For Semantic Video Indexing And Near-Duplicate Retrieval, Yu-Gang Jiang, Chong-Wah Ngo

Research Collection School Of Computing and Information Systems

Bag-of-visual-words (BoW) has recently become a popular representation to describe video and image content. Most existing approaches, nevertheless, neglect inter-word relatedness and measure similarity by bin-to-bin comparison of visual words in histograms. In this paper, we explore the linguistic and ontological aspects of visual words for video analysis. Two approaches, soft-weighting and constraint-based earth mover’s distance (CEMD), are proposed to model different aspects of visual word linguistics and proximity. In soft-weighting, visual words are cleverly weighted such that the linguistic meaning of words is taken into account for bin-to-bin histogram comparison. In CEMD, a cross-bin matching algorithm is formulated such …


A Social Relation Aware Routing Protocol For Mobile Ad Hoc Networks, Jisun An, Yangwoo Ko, Dongman Lee Mar 2009

A Social Relation Aware Routing Protocol For Mobile Ad Hoc Networks, Jisun An, Yangwoo Ko, Dongman Lee

Research Collection School Of Computing and Information Systems

In this paper, we propose a social relation aware routing protocol for mobile ad hoc networks, which is designed for content sharing mobile social applications. Since a content can be shared by a group of users who have similar interests, the similarity of users' interests is a good metric to predict who will consume which contents. Shared interests can be exploited in routing and replication of content request and reply to achieve enhanced efficacy in content sharing. Since routing determines which content will be forwarded by whom, a route selected based on similarity of interest increases the utilization of contents …


Web Query Recommendation Via Sequential Query Prediction, Qi He, Daxin Jiang, Zhen Liao, Steven C. H. Hoi, Kuiyu Chang, Ee Peng Lim, Hang Li Mar 2009

Web Query Recommendation Via Sequential Query Prediction, Qi He, Daxin Jiang, Zhen Liao, Steven C. H. Hoi, Kuiyu Chang, Ee Peng Lim, Hang Li

Research Collection School Of Computing and Information Systems

Web query recommendation has long been considered a key feature of search engines. Building a good Web query recommendation system, however, is very difficult due to the fundamental challenge of predicting users' search intent, especially given the limited user context information. In this paper, we propose a novel "sequential query prediction" approach that tries to grasp a user's search intent based on his/her past query sequence and its resemblance to historical query sequence models mined from massive search engine logs. Different query sequence models were examined, including the naive variable length N-gram model, Variable Memory Markov (VMM) model, and our …


Server-Assisted Context-Dependent Pervasive Wellness Monitoring, Archan Misra, Ben Falchuk, Shoshana Loeb Mar 2009

Server-Assisted Context-Dependent Pervasive Wellness Monitoring, Archan Misra, Ben Falchuk, Shoshana Loeb

Research Collection School Of Computing and Information Systems

Recent research on remote health monitoring solutions has focused largely on developing context-dependent, streamprocessing capabilities on a personal mobile hub (typically, a cellphone) for energy-efficient transmission of data collected from a set of body-worn medical sensors. In this paper, we argue that commercial deployment of such pervasive wellness monitoring will require the extension of such ‘context dependency’ to the process of data collection (from the sensors to the mobile device) as well. In particular, the utilization of an individuals non-medical activity context, by the cellphone, in coordination with a backend server, is posited to be the key to supporting important …


Electronic Commerce Research And Applications Ecra Co-Editors' Introduction For Volume 8, Issue 2, March - April 2009, Robert J. Kauffman, Patrick Y. K. Chau, Terry R. Payne, J. Christopher Westland Mar 2009

Electronic Commerce Research And Applications Ecra Co-Editors' Introduction For Volume 8, Issue 2, March - April 2009, Robert J. Kauffman, Patrick Y. K. Chau, Terry R. Payne, J. Christopher Westland

Research Collection School Of Computing and Information Systems

Many efforts are occurring around the world to improve supply chain performance to best-practice levels to improve the profitability of manufacturing and service firms. As a result, there is great interest among industry leaders and academic researchers to find ways to coordinate and streamline all of the activities in the supply procurement process as a basis for cost management, managed quality, and strategic competitiveness. With the Internet, the possibility of implementing many innovative new approaches to procurement has driven firms to want much higher performance than they currently seem to be able to achieve. Some of the innovations include dynamic …


Continuous Visible Nearest Neighbour Queries, Yunjun Gao, Baihua Zheng, Wang-Chien Lee, Gencai Chen Mar 2009

Continuous Visible Nearest Neighbour Queries, Yunjun Gao, Baihua Zheng, Wang-Chien Lee, Gencai Chen

Research Collection School Of Computing and Information Systems

In this paper, we identify and solve a new type of spatial queries, called continuous visible nearest neighbor (CVNN) search. Given a data set P, an obstacle set O, and a query line segment q, a CVNN query returns a set of (p, R) tuples such that p ? P is the nearest neighbor (NN) to every point r along the interval R ? q as well as p is visible to r. Note that p may be NULL, meaning that all points in P are invisible to all points in R, due to the obstruction of some obstacles in …


House Of Cards, M. Thulasidas Mar 2009

House Of Cards, M. Thulasidas

Research Collection School Of Computing and Information Systems

We are in dire straits - no doubt about it. Our banks and financial edifices are collapsing. Those left standing also look shaky. The financial industry as a whole is battling to survive. And, as its frontline warriors, we will bear the brunt of the blood- bath sure to ensue any minute now. A good opportunity to play solitaire?


Programmable Presence Virtualization For Next-Generation Context-Based Applications, Arup Acharya, Nilanjan Banerjee, Dipanjan Chakraborty, Koustuv Dasgupta, Archan Misra, Shachi Sharma, Xiping Wang, Charles P. Wright Mar 2009

Programmable Presence Virtualization For Next-Generation Context-Based Applications, Arup Acharya, Nilanjan Banerjee, Dipanjan Chakraborty, Koustuv Dasgupta, Archan Misra, Shachi Sharma, Xiping Wang, Charles P. Wright

Research Collection School Of Computing and Information Systems

Presence, broadly defined as an event publish-notification infrastructure for converged applications, has emerged as a key mechanism for collecting and disseminating context attributes for next-generation services in both enterprise and provider domains. Current presence-based solutions and products lack in the ability to a) support flexible user-defined queries over dynamic presence data and b) derive composite presence from multiple provider domains. Accordingly, current uses of context are limited to individual domains/organizations and do not provide a programmable mechanism for rapid creation of context-aware services. This paper describes a presence virtualization architecture, where a virtualized presence server receives customizable queries from multiple …


Pat: Towards Flexible Verification Under Fairness, Jun Sun, Yang Liu, Jin Song Dong, Jun Pang Feb 2009

Pat: Towards Flexible Verification Under Fairness, Jun Sun, Yang Liu, Jin Song Dong, Jun Pang

Research Collection School Of Computing and Information Systems

Recent development on distributed systems has shown that a variety of fairness constraints (some of which are only recently defined) play vital roles in designing self-stabilizing population protocols. Current practice of system analysis is, however, deficient under fairness. In this work, we present PAT, a toolkit for flexible and efficient system analysis under fairness. A unified algorithm is proposed to model check systems with a variety of fairness effectively in two different settings. Empirical evaluation shows that PAT complements existing model checkers in terms of fairness. We report that previously unknown bugs have been revealed using PAT against systems functioning …