Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Singapore Management University

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 12061 - 12090 of 13080

Full-Text Articles in Entire DC Network

Dynamically-Optimized Context In Recommender Systems, Ghim-Eng Yap, Ah-Hwee Tan, Hwee-Hwa Pang May 2005

Dynamically-Optimized Context In Recommender Systems, Ghim-Eng Yap, Ah-Hwee Tan, Hwee-Hwa Pang

Research Collection School Of Computing and Information Systems

Traditional approaches to recommender systems have not taken into account situational information when making recommendations, and this seriously limits the relevance of the results. This paper advocates context-awareness as a promising approach to enhance the performance of recommenders, and introduces a mechanism to realize this approach. We present a framework that separates the contextual concerns from the actual recommendation module, so that contexts can be readily shared across applications. More importantly, we devise a learning algorithm to dynamically identify the optimal set of contexts for a specific recommendation task and user. An extensive series of experiments has validated that our …

Go to article

'Treaties', 'Agreements', 'Contracts' And 'Commitments' - What's In A Name? The Legal Force And Meaning Of Different Forms Of Agreement Making, David Llewelyn, Maureen Tehan May 2005

'Treaties', 'Agreements', 'Contracts' And 'Commitments' - What's In A Name? The Legal Force And Meaning Of Different Forms Of Agreement Making, David Llewelyn, Maureen Tehan

Research Collection Yong Pung How School Of Law

The multi-dimensional nature of treaty and agreement making has assumed a central focus in the conduct of relations between Indigenous peoples and settlers in Australia and elsewhere. Whether as a means of resolving disputes, delivering government programmes, or establishing common understandings, agreement making, however defined and named, has become the key tool for engagement between Indigenous and non-Indigenous Australians. Agreements come in all shapes and sizes ranging from registered Indigenous Land Use Agreements (ILUA) to Statements of Commitment, Memorandums of Understanding and Regional Agreements. In other jurisdictions these may be called 'treaties'. This paper examines the plethora of agreements in …

Go to article

Protecting Group Dynamic Information In Large Scale Multicast Groups, Yongdong Wu, Tieyan Li, Robert H. Deng May 2005

Protecting Group Dynamic Information In Large Scale Multicast Groups, Yongdong Wu, Tieyan Li, Robert H. Deng

Research Collection School Of Computing and Information Systems

Existing key management schemes can secure group communication efficiently, but are failed on protecting the Group Dynamic Information (GDI) that may undermine group privacy. Recently, Sun et al. proposed a scheme to hide the GDI with batch updating and phantom members inserting so that an adversary is not able to estimate the number of group members. In this paper, we first point out that their scheme is only applicable in departure-only group communication instead of the common conference groups. Secondly, we introduce our method of estimating the group size at a higher confidence level given a prior departure probability. Further, …

Go to article

A New Architecture For User Authentication And Key Exchange Using Password For Federated Enterprises, Yanjiang Yang, Feng Bao, Robert H. Deng May 2005

A New Architecture For User Authentication And Key Exchange Using Password For Federated Enterprises, Yanjiang Yang, Feng Bao, Robert H. Deng

Research Collection School Of Computing and Information Systems

The rapid rise of federated enterprises entails a new way of trust management by the fact that an enterprise can account for partial trust of its affiliating organizations. On the other hand, password has historically been used as a main means for user authentication because of operational simplicity. We are thus motivated to explore the use of short password for user authentication and key exchange in the context of federated enterprises. Exploiting the special structure of a federated enterprise, our proposed new architecture comprises an external server managed by each affiliating organization and a central server managed by the enterprise …

Go to article

Secure Human Communications Based On Biometrics Signals, Yongdong Wu, Feng Bao, Robert H. Deng May 2005

Secure Human Communications Based On Biometrics Signals, Yongdong Wu, Feng Bao, Robert H. Deng

Research Collection School Of Computing and Information Systems

User authentication is the first and probably the most challenging step in achieving secure person-to-person communications. Most of the existing authentication schemes require communicating parties either share a secret/password or know each other's public key. In this paper we suggest a novel user authentication scheme that is easy to use and overcomes the requirements of sharing password or public keys. Our scheme allows two human users to perform mutual authentication and have secure communications over an open channel by exchanging biometrics signals (e. g., voice or video signals). In addition to user authentication, our scheme establishes a secret session key …

Go to article

Tosa: A Near-Optimal Scheduling Algorithm For Multi-Channel Data Broadcast, Baihua Zheng, Xia Xu, Xing Jin, Dik Lun Lee May 2005

Tosa: A Near-Optimal Scheduling Algorithm For Multi-Channel Data Broadcast, Baihua Zheng, Xia Xu, Xing Jin, Dik Lun Lee

Research Collection School Of Computing and Information Systems

Wireless broadcast is very suitable for delivering information to a large user population. In this paper, we concentrate on data allocation methods for multiple broadcast channels. To the best of our knowledge, this is the first allocation model that takes into the consideration of items' access frequencies, items' lengths. and bandwidth of different channels. We first derive the optimal average expected delay for multiple channels for the general case where data access frequencies, data sizes, and channel bandwidths can all be non-uniform. Second, we develop TOSA, a multi-channel allocation method that does not assume a uniform broadcast schedule for data …

Go to article

Event-Driven Document Selection For Terrorism, Zhen Sun, Ee Peng Lim, Kuiyu Chang, Teng-Kwee Ong, Rohan Kumar Gunaratna May 2005

Event-Driven Document Selection For Terrorism, Zhen Sun, Ee Peng Lim, Kuiyu Chang, Teng-Kwee Ong, Rohan Kumar Gunaratna

Research Collection School Of Computing and Information Systems

In this paper, we examine the task of extracting information about terrorism related events hidden in a large document collection. The task assumes that a terrorism related event can be described by a set of entity and relation instances. To reduce the amount of time and efforts in extracting these event related instances, one should ideally perform the task on the relevant documents only. We have therefore proposed some document selection strategies based on information extraction (IE) patterns. Each strategy attempts to select one document at a time such that the gain of event related instance information is maximized. Our …

Go to article

Mining Mobile Group Patterns: A Trajectory-Based Approach, San-Yih Hwang, Ying-Han Liu, Jeng-Kuen Chiu, Ee Peng Lim May 2005

Mining Mobile Group Patterns: A Trajectory-Based Approach, San-Yih Hwang, Ying-Han Liu, Jeng-Kuen Chiu, Ee Peng Lim

Research Collection School Of Computing and Information Systems

In this paper, we present a group pattern mining approach to derive the grouping information of mobile device users based on a trajectory model. Group patterns of users are determined by distance threshold and minimum time duration. A trajectory model of user movement is adopted to save storage space and to cope with untracked or disconnected location data. To discover group patterns, we propose ATGP algorithm and TVG-growth that are derived from the Apriori and VG-growth algorithms respectively.

Go to article

Information Dissemination Via Wireless Broadcast, Baihua Zheng, Dik Lun Lee May 2005

Information Dissemination Via Wireless Broadcast, Baihua Zheng, Dik Lun Lee

Research Collection School Of Computing and Information Systems

Unrestricted mobility adds a new dimension to data access methodology--- one that must be addressed before true ubiquity can be realized.

Go to article

Synthesizing E-Government Stage Models – A Meta-Synthesis Based On Meta-Ethnography Approach, Keng Siau, Y. Long May 2005

Synthesizing E-Government Stage Models – A Meta-Synthesis Based On Meta-Ethnography Approach, Keng Siau, Y. Long

Research Collection School Of Computing and Information Systems

The growing interest in e-government raises the question of stages in e-government development. A few stage models for e-government have been proposed. Without a common e-government stage model, different research in e-government may be based on different stage models. This presents a difficulty in comparing and understanding different research results. In this research, we synthesize the existing e-government stage models so that there is a common frame of reference for researchers and practitioners in the area.

Go to article

Dynamically Optimized Context In Recommender Systems, Ghim-Eng Yap, Ah-Hwee Tan, Hwee Hwa Pang May 2005

Dynamically Optimized Context In Recommender Systems, Ghim-Eng Yap, Ah-Hwee Tan, Hwee Hwa Pang

Research Collection School Of Computing and Information Systems

Traditional approaches to recommender systems have not taken into account situational information when making recommendations, and this seriously limits the relevance of the results. This paper advocates context-awareness as a promising approach to enhance the performance of recommenders, and introduces a mechanism to realize this approach. We present a framework that separates the contextual concerns from the actual recommendation module, so that contexts can be readily shared across applications. More importantly, we devise a learning algorithm to dynamically identify the optimal set of contexts for a specific recommendation task and user. An extensive series of experiments has validated that our …

Go to article

Leveraging Global Resources: A Distributed Process Maturity Framework For Software Product Development, Narayan Ramasubbu, M. S. Krishnan, Prasad Kompalli May 2005

Leveraging Global Resources: A Distributed Process Maturity Framework For Software Product Development, Narayan Ramasubbu, M. S. Krishnan, Prasad Kompalli

Research Collection School Of Computing and Information Systems

Distributed software development is pervasive in the software industry today as companies vie to leverage global resources. However, popular quality and process frameworks don?t specifically address the key processes needed for managing distributed software development. This practitioner-oriented, evolutionary process maturity framework for globally distributed software development features 24 new key process areas essential for managing distributed software product development and for continuously improving product management capabilities. An assessment survey helps practitioners implement the framework. In this article, the authors detail the framework and assessment survey, as well as report their experiences implementing the framework at a leading global firm. The …

Go to article

The Impact Of Ownership Structure On Wage Intensity In Japanese Corporations, Toru Yoshikawa, Phillip H. Phan, Parthiban David Apr 2005

The Impact Of Ownership Structure On Wage Intensity In Japanese Corporations, Toru Yoshikawa, Phillip H. Phan, Parthiban David

Research Collection Lee Kong Chian School Of Business

The authors studied the effect of ownership structure on human capital investments as indicated by wage intensity, defined as the ratio of expenditure on employee wages to sales, in a sample of 996 Japanese manufacturing firms during their economic recession of 1998-2002. They found that domestic shareholders, with interests beyond financial considerations, enhance wage intensity, especially when performance is low, and thereby safeguard human capital investments. Foreign shareholders with sole interest in financial returns have an opposite effect; they reduce wage intensity when firm performance is low.

Go to article

Spatial Orientation Strategies In Morris-Type Virtual Water Task For Humans, Janos Kallai, Tamas Makany, Kazmer Karadi, William J. Jacobs Apr 2005

Spatial Orientation Strategies In Morris-Type Virtual Water Task For Humans, Janos Kallai, Tamas Makany, Kazmer Karadi, William J. Jacobs

Research Collection Lee Kong Chian School Of Business

The present study characterized frequent motion patterns (search strategies) that occurred during spatial navigation in a virtual maze. The research focused on identifying and characterizing some search strategies, the temporal progression of strategy-use, and their role in spatial performance. Participants were 112 undergraduate students (42 males and 70 females). We identified three search strategies that predicted spatial performance. Enfilading refers to an approach-withdrawal pattern of active exploration near a target location. Thigmotaxis refers to a search strategy that involves continuous contact with the circular wall of the maze. Visual scan involves active visual exploration while the subject remains in a …

Go to article

Mining Social Network From Spatio-Temporal Events, Hady Wirawan Lauw, Ee Peng Lim, Teck Tim Tan, Hwee Hwa Pang Apr 2005

Mining Social Network From Spatio-Temporal Events, Hady Wirawan Lauw, Ee Peng Lim, Teck Tim Tan, Hwee Hwa Pang

Research Collection School Of Computing and Information Systems

Knowing patterns of relationship in a social network is very useful for law enforcement agencies to investigate collaborations among criminals, for businesses to exploit relationships to sell products, or for individuals who wish to network with others. After all, it is not just what you know, but also whom you know, that matters. However, finding out who is related to whom on a large scale is a complex problem. Asking every single individual would be impractical, given the huge number of individuals and the changing dynamics of relationships. Recent advancement in technology has allowed more data about activities of individuals …

Go to article

Walverine: A Walrasian Trading Agent, Shih-Fen Cheng, Evan Leung, Kevin M. Lochner, Kevin O'Malley, Daniel M. Reeves, Julian L. Schvartzman, Michael P. Wellman Apr 2005

Walverine: A Walrasian Trading Agent, Shih-Fen Cheng, Evan Leung, Kevin M. Lochner, Kevin O'Malley, Daniel M. Reeves, Julian L. Schvartzman, Michael P. Wellman

Research Collection School Of Computing and Information Systems

TAC-02 was the third in a series of Trading Agent Competition events fostering research in automating trading strategies by showcasing alternate approaches in an open-invitation market game. TAC presents a challenging travel-shopping scenario where agents must satisfy client preferences for complementary and substitutable goods by interacting through a variety of market types. Michigan's entry, Walverine, bases its decisions on a competitive (Walrasian) analysis of the TAC travel economy. Using this Walrasian model, we construct a decision-theoretic formulation of the optimal bidding problem, which Walverine solves in each round of bidding for each good. Walverine's optimal bidding approach, as well as …

Go to article

Privacy And Ownership Preserving Of Outsourced Medical Data, Elisa Bertino, Beng Chin Ooi, Yanjiang Yang, Robert H. Deng Apr 2005

Privacy And Ownership Preserving Of Outsourced Medical Data, Elisa Bertino, Beng Chin Ooi, Yanjiang Yang, Robert H. Deng

Research Collection School Of Computing and Information Systems

The demand for the secondary use of medical data is increasing steadily to allow for the provision of better quality health care. Two important issues pertaining to this sharing of data have to be addressed: one is the privacy protection for individuals referred to in the data; the other is copyright protection over the data. In this paper, we present a unified framework that seamlessly combines techniques of binning and digital watermarking to attain the dual goals of privacy and copyright protection. Our binning method is built upon an earlier approach of generalization and suppression by allowing a broader concept …

Go to article

Providing Efficient Certification Services Against Active Attacks In Ad Hoc Networks, Bo Zhu, Guilin Wang, Zhiguo Wan, Mohan S. Kankanhalli, Feng Bao, Robert H. Deng Apr 2005

Providing Efficient Certification Services Against Active Attacks In Ad Hoc Networks, Bo Zhu, Guilin Wang, Zhiguo Wan, Mohan S. Kankanhalli, Feng Bao, Robert H. Deng

Research Collection School Of Computing and Information Systems

Most of previous research work in key management can only resist passive attacks, such as dropping the certificate request, and are vulnerable under active attacks, such as returning a fake reply to the node requesting the certification service. In this paper, we propose two algorithms to address both security and efficiency issues of certification services in ad hoc networks. Both of the algorithms can resist active attacks. In addition, simulation results show that, compared to the previous works, our second algorithm is not only much faster in a friendly environment, but it also works well in a hostile environment in …

Go to article

Integrating User Feedback Log Into Relevance Feedback By Coupled Svm For Content-Based Image Retrieval, Steven C. H. Hoi, Michael R. Lyu, Rong Jin Apr 2005

Integrating User Feedback Log Into Relevance Feedback By Coupled Svm For Content-Based Image Retrieval, Steven C. H. Hoi, Michael R. Lyu, Rong Jin

Research Collection School Of Computing and Information Systems

Relevance feedback has been shown as an important tool to boost the retrieval performance in content-based image retrieval. In the past decade, various algorithms have been proposed to formulate relevance feedback in contentbased image retrieval. Traditional relevance feedback techniques mainly carry out the learning tasks by focusing lowlevel visual features of image content with little consideration on log information of user feedback. However, from a long-term learning perspective, the user feedback log is one of the most important resources to bridge the semantic gap problem in image retrieval. In this paper we propose a novel technique to integrate the log …

Go to article

Ais Sighci Position Paper, Dennis Galletta, Ping Zhang, Fiona Fui-Hoon Nah Apr 2005

Ais Sighci Position Paper, Dennis Galletta, Ping Zhang, Fiona Fui-Hoon Nah

Research Collection School Of Computing and Information Systems

The upcoming ACM SIGCHI Development Consortium is aimed at meeting the needs of multidisciplinary professionals that must choose among a variety of professional associations and their events. The position of AIS' (Association for Information Systems) SIGHCI is that the main problem lies in the deep chasms that separate the literatures of the related disciplines, and the solution is to provide an umbrella organization that enables a more organized federation of disciplines, groups, and associations. Problems identified include differences in terminology, competition for scarce resources, differences in how publications in various outlets are valued, and confusion about where should be the …

Go to article

Proactive Caching For Spatial Queries In Mobile Environments, Haibo Hu, Jianliang Xu, Wing Sing Wong, Baihua Zheng, Dik Lun Lee, Wang-Chien Lee Apr 2005

Proactive Caching For Spatial Queries In Mobile Environments, Haibo Hu, Jianliang Xu, Wing Sing Wong, Baihua Zheng, Dik Lun Lee, Wang-Chien Lee

Research Collection School Of Computing and Information Systems

Semantic caching enables mobile clients to answer spatial queries locally by storing the query descriptions together with the results. However, it supports only a limited number of query types, and sharing results among these types is difficult. To address these issues, we propose a proactive caching model which caches the result objects as well as the index that supports these objects as the results. The cached index enables the objects to be reused for all common types of queries. We also propose an adaptive scheme to cache such an index, which further optimizes the query response time for the best …

Go to article

Predictive Neural Networks For Gene Expression Data Analysis, Ah-Hwee Tan, Hong Pan Apr 2005

Predictive Neural Networks For Gene Expression Data Analysis, Ah-Hwee Tan, Hong Pan

Research Collection School Of Computing and Information Systems

Gene expression data generated by DNA microarray experiments have provided a vast resource for medical diagnosis and disease understanding. Most prior work in analyzing gene expression data, however, focuses on predictive performance but not so much on deriving human understandable knowledge. This paper presents a systematic approach for learning and extracting rule-based knowledge from gene expression data. A class of predictive self-organizing networks known as Adaptive Resonance Associative Map (ARAM) is used for modelling gene expression data, whose learned knowledge can be transformed into a set of symbolic IF-THEN rules for interpretation. For dimensionality reduction, we illustrate how the system …

Go to article

Sustainable External Debt Levels: Estimates For Selected Asian Countries, Roberto S. Mariano, Delano Villanueva Mar 2005

Sustainable External Debt Levels: Estimates For Selected Asian Countries, Roberto S. Mariano, Delano Villanueva

Research Collection School Of Economics

High ratios of external debt to GDP in selected Asian countries have contributed to the initiation, propagation, and severity of the financial and economic crises in recent years, reflecting runaway fiscal deficits and excessive foreign borrowing by the private sector. Applying the formal framework proposed by Villanueva (2003) to a selected group of Asian countries, the research estimates the external debt thresholds beyond which further debt accumulation will have negative effects on growth and will become unsustainable. The framework is an extension of the standard neoclassical growth model that incorporates global capital markets. ‘Sustainability’ is measured in terms of the …

Go to article

Some Patterns Of Market Shares Of Brands Within And Across Product Categories, Rajeev Kohli, Raaj Sah Mar 2005

Some Patterns Of Market Shares Of Brands Within And Across Product Categories, Rajeev Kohli, Raaj Sah

Research Collection School Of Economics

This paper: (i) reports an empirical regularity in the market shares of brands; (ii) presents a theoretical framework for understanding the observed regularity; (iii) adduces additional empirical consequences of the framework, which are some counterintuitive relationships among market shares of brands across different product categories; and (iv) presents empirical evidence for these consequences, thus providing additional support for the theoretical framework. Our cross-sectional data on market shares consists of 1171 brands in 91 product categories of foods and sporting goods sold in the US. If we assign a lower rank to a brand with a higher market share, then the …

Go to article

The Performance Of Value And Growth Portfolios In East Asia Before The Asian Financial Crisis, David K. Ding, Jia-Leng Chua, Thomas A. Fetherston Mar 2005

The Performance Of Value And Growth Portfolios In East Asia Before The Asian Financial Crisis, David K. Ding, Jia-Leng Chua, Thomas A. Fetherston

Research Collection Lee Kong Chian School Of Business

We examine value and growth portfolios in seven East Asian countries just before the onslaught of the 1997 Asian Financial Crisis. The value premiums in these countries, except in Indonesia, Taiwan, and Thailand, are found to be mainly positive. After controlling for firm size, risk, liquidity, and growth potential, we find higher returns among value stocks with a small firm size and low growth potential in Hong Kong and Malaysia. In Japan and Singapore, higher returns are found in growth portfolios with a small firm size and low growth potential. Growth stocks in Taiwan with a small firm size, and …

Go to article

Video Text Detection And Segmentation For Optical Character Recognition, Chong-Wah Ngo, Chi-Kwong Chan Mar 2005

Video Text Detection And Segmentation For Optical Character Recognition, Chong-Wah Ngo, Chi-Kwong Chan

Research Collection School Of Computing and Information Systems

In this paper, we present approaches to detecting and segmenting text in videos. The proposed video-text-detection technique is capable of adaptively applying appropriate operators for video frames of different modalities by classifying the background complexities. Effective operators such as the repeated shifting operations are applied for the noise removal of images with high edge density. Meanwhile, a text-enhancement technique is used to highlight the text regions of low-contrast images. A coarse-to-fine projection technique is then employed to extract text lines from video frames. Experimental results indicate that the proposed text-detection approach is superior to the machine-learning-based (such as SVM and …

Go to article

Do We Stand On Common Ground? A Threat Appraisal Model For Terror Alerts Issued By The Department Of Homeland Security, Augustine Pang, Yan Jin, Glen T. Cameron Mar 2005

Do We Stand On Common Ground? A Threat Appraisal Model For Terror Alerts Issued By The Department Of Homeland Security, Augustine Pang, Yan Jin, Glen T. Cameron

Research Collection Lee Kong Chian School Of Business

Having developed a threat appraisal model to examine the fabric and faces of threat, and how it can becommunicated, the authors empirically test the model on an ongoing issue, the issuance of terror alerts bythe Department of Homeland Security (DHS), on how threat is appraised by DHS, and the conservativeand liberal audiences. Findings showed a shared view by the DHS and the conservative audiences whilethe liberal audiences thought otherwise. Though there appear to be consensus in threat communication,more internal consistency within DHS is needed to optimize its effectiveness.

Go to article

Corruption Across Countries And Regions: Some Consequences Of Local Osmosis, Raaj Sah Mar 2005

Corruption Across Countries And Regions: Some Consequences Of Local Osmosis, Raaj Sah

Research Collection School Of Economics

Large and persistent differences in corruption across comparable countries is a challenging research issue. Even more intriguing are such differences across regions within the same country, because the typically considered socioeconomic and governance characteristics are generally more similar across such regions than across different countries. This paper's principal theme is that individuals’ perceptions of their environments are influenced by the realities that they have faced in the past; these perceptions affect their current and future actions; which in turn influence the current and future realities. An articulation and analysis of these dynamics yields significant observations concerning individuals’ behavior and societal …

Go to article

Competing At The Frontier: The Changing Role Of Technology Policy In Singapore's Economic Strategy, Winston T. H. Koh, Poh Kam Wong Mar 2005

Competing At The Frontier: The Changing Role Of Technology Policy In Singapore's Economic Strategy, Winston T. H. Koh, Poh Kam Wong

Research Collection School Of Economics

For an economy competing at the global frontier, an innovation-based growth strategy requires a well-developed technological infrastructure, a set of capabilities-focused technology policies, as well as an institutional environment that stimulates innovation and entrepreneurship. This paper examines the role played by science and technology policy in an economy's transition to an innovation-based growth strategy. We discuss the challenges governments face as they restructure economic institutions to deepen R&D capabilities and encourage technology creation. We review Singapore's experience in this regard and assess its ongoing efforts to remake itself to compete at the global frontier.

Go to article

Scheduling Queries To Improve The Freshness Of A Website, Haifeng Liu, Wee-Keong Ng, Ee Peng Lim Mar 2005

Scheduling Queries To Improve The Freshness Of A Website, Haifeng Liu, Wee-Keong Ng, Ee Peng Lim

Research Collection School Of Computing and Information Systems

The World Wide Web is a new advertising medium that corporations use to increase their exposure to consumers. Very large websites whose content is derived from a source database need to maintain a freshness that reflects changes that are made to the base data. This issue is particularly significant for websites that present fast-changing information such as stock-exchange information and product information. In this article, we formally define and study the freshness of a website that is refreshed by a scheduled set of queries that fetch fresh data from the databases. We propose several online-scheduling algorithms and compare the performance …

Go to article

First Prev Next Last