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Content-Aware Authentication Of Motion Jpeg2000 Stream In Lossy Networks, Yongdong Wu, Robert H. Deng Nov 2003

Content-Aware Authentication Of Motion Jpeg2000 Stream In Lossy Networks, Yongdong Wu, Robert H. Deng

Research Collection School Of Computing and Information Systems

Stream authentication schemes (SAS) aim to achieve effective authentication of multicast streams over lossy networks. Almost all the existing SASs is designed for stream data integrity protection only. In this paper, we argue that content integrity protection is more important than data integrity to human users. We present a content-aware SAS in motion JPEG2000 streaming. In our scheme, a chunk of JPEG2000 codestreams is encapsulated into a block of packets using multiple description coding (MDC). Our MDC exploits the inherent structure of motion JPEG2000 codestreams and is used to preserve the semanteme/content of the stream over lossy networks. To achieve …

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Prospect Theory And Institutional Investors, Melvyn Teo, Paul G. J. O'Connell Nov 2003

Prospect Theory And Institutional Investors, Melvyn Teo, Paul G. J. O'Connell

Research Collection Lee Kong Chian School Of Business

There is ample evidence that past performance affects the trading decisions of individual investors. This paper looks at this issue using a detailed database of currency trading decisions of institutional investors. Past performance manifestly affects currency risk-taking in this group, but the sign and magnitude of the effect runs counter to much of the existing theory and evidence. There is no evidence whatsoever of disposition effects; rather, the dominant characteristic is aggressive risk reduction in the wake of losses. This effect is more prominent later in the year, and among older and more experienced funds. A modified version of the …

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Pricing And Qos Of Information Services In A Competitive Market, Zhen Liu, Laura Wynter, Cathy Xia Nov 2003

Pricing And Qos Of Information Services In A Competitive Market, Zhen Liu, Laura Wynter, Cathy Xia

Research Collection School Of Computing and Information Systems

Design of e-commerce services that are competitive in a quickly responding market requires the analyses of prices and price structures. We develop a general model of an e-commerce market that allows us to analyze optimal price structures, both flat and usage-based. Based on the price structure of a major web hosting provider, we consider single-tier and two-tier (burst-rate) pricing, and our result suggests that the more complex two-tier structure may not be worth the marketing effort, as the firm's equilibrium profits will not increase through the use of this structure. An essential feature of our approach is that we model …

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Web Unit Mining: Finding And Classifying Subgraphs Of Web Pages, Aixin Sun, Ee Peng Lim Nov 2003

Web Unit Mining: Finding And Classifying Subgraphs Of Web Pages, Aixin Sun, Ee Peng Lim

Research Collection School Of Computing and Information Systems

In web classification, most researchers assume that the objects to classify are individual web pages from one or more web sites. In practice, the assumption is too restrictive since a web page itself may not always correspond to a concept instance of some semantic concept (or category) given to the classification task. In this paper, we want to relax this assumption and allow a concept instance to be represented by a subgraph of web pages or a set of web pages. We identify several new issues to be addressed when the assumption is removed, and formulate the web unit mining …

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Task Allocation Via Multi-Agent Coalition Formation: Taxonomy, Algorithms And Complexity, Hoong Chuin Lau, L. Zhang Nov 2003

Task Allocation Via Multi-Agent Coalition Formation: Taxonomy, Algorithms And Complexity, Hoong Chuin Lau, L. Zhang

Research Collection School Of Computing and Information Systems

Coalition formation has become a key topic in multiagent research. In this paper, we propose a preliminary classification for the coalition formation problem based on three driving factors (demands, resources and profit objectives). We divide our analysis into 5 cases. For each case, we present algorithms and complexity results. We anticipate that with future research, this classification can be extended in similar fashion to the comprehensive classification for the job scheduling problem.

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A Robust Dissolve Detector By Support Vector Machine, Chong-Wah Ngo Nov 2003

A Robust Dissolve Detector By Support Vector Machine, Chong-Wah Ngo

Research Collection School Of Computing and Information Systems

In this paper, we propose a novel approach for the robust detection and classification of dissolve sequences in videos. Our approach is based on the multi-resolution representation of temporal slices extracted from 3D image volume. At the low-resolution (LR) scale, the problem of dissolve detection is reduced as cut transition detection. At the highresolution (HR) space, Gabor wavelet features are computed for regions that surround the cuts located at LR scale. The computed features are then input to support vector machines for pattern classification. Encouraging results have been obtained through experiments.

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A Survey On Physical Delivery Versus Cash Settlement In Futures Contracts, Donald Lien, Yiu Kuen Tse Nov 2003

A Survey On Physical Delivery Versus Cash Settlement In Futures Contracts, Donald Lien, Yiu Kuen Tse

Research Collection School Of Economics

A futures contract may adopt physical delivery or cash settlement to liquidate open positions after the maturity day. While traditionally physical delivery specification is favored, exchanges have recently turned to examine cash settlement possibilities. This paper summarizes current literature on settlement specifications with emphases on market manipulation, cash index construction, and hedging effectiveness comparisons

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Tests Of Functional Form And Heteroscedasticity, Zhenlin Yang, Yiu Kuen Tse Nov 2003

Tests Of Functional Form And Heteroscedasticity, Zhenlin Yang, Yiu Kuen Tse

Research Collection School Of Economics

This paper considers tests of misspecification in a heteroscedastic transformation model. We derive Lagrange multiplier (LM) statistics for (i) testing functional form and heteroscedasticity jointly, (ii) testing functional form in the presence of heteroscedasticity, and (iii) testing heteroscedasticity in the presence of data transformation. We present LM statistics based on the expected information matrix. For cases (i) and (ii), this is done assuming the Box-Cox transformation. For case (iii), the test does not depend on whether the functional form is estimated or pre-specified. Small-sample properties of the tests are assessed by Monte Carlo simulation, and comparisons are made with the …

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Synchronization Of Lecture Videos And Electronic Slides By Video Text Analysis, Feng Wang, Chong-Wah Ngo, Ting-Chuen Pong Nov 2003

Synchronization Of Lecture Videos And Electronic Slides By Video Text Analysis, Feng Wang, Chong-Wah Ngo, Ting-Chuen Pong

Research Collection School Of Computing and Information Systems

An essential goal of structuring lecture videos captured in live presentation is to provide a synchronized view of video clips and electronic slides. This paper presents an automatic approach to match video clips and slides based on the analysis of text embedded in lecture videos. We describe a method to reconstruct high-resolution video texts from multiple keyframes for robust OCRrecognition. A two-stage matching algorithm based on the title and content similarity measures between video clips and slides is also proposed.

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Larger Issues At Stake In Unnatural Sex Debate, Seow Hon Tan Nov 2003

Larger Issues At Stake In Unnatural Sex Debate, Seow Hon Tan

Research Collection Yong Pung How School Of Law

The recent debate about the criminal prohibition of oral sex provides an occasion for considering larger, related issues. However prevalent the practice of oral sex and however archaic Section 377 of the Penal Code seems to those pushing for its repeal, the arguments offered have tended to take a piecemeal approach and display an ignorance of or disregard for the larger interests at stake.

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Manpower Allocation With Time Windows And Job Teaming Constraints, Xi Li, Yan Zhi Li, Andrew Lim, Brian Rodrigues Nov 2003

Manpower Allocation With Time Windows And Job Teaming Constraints, Xi Li, Yan Zhi Li, Andrew Lim, Brian Rodrigues

Research Collection Lee Kong Chian School Of Business

In the Manpower Allocation Problem with Time Windows and Job-Teaming Constraints (MAPTWTC), we have a set of jobs located at various locations where each job requires a team of workers. Each job has a time window and a job duration, during which everyone on the team has to be present. The job requirement is satisfied if and only if the required composite team works for long enough duration within the job's time window. The objective of the problem is find a schedule to minimize a weighted sum of the total number of workers, the total travelling distances of all workers …

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Validating Digital Signatures Without Ttp’S Time-Stamping And Certificate Revocation, Jianying Zhou, Feng Bao, Robert H. Deng Oct 2003

Validating Digital Signatures Without Ttp’S Time-Stamping And Certificate Revocation, Jianying Zhou, Feng Bao, Robert H. Deng

Research Collection School Of Computing and Information Systems

In non-repudiation services where digital signatures usually serve as irrefutable cryptographic evidence for dispute resolution, trusted time-stamping and certificate revocation services, although very costly in practice, must be available, to prevent big loss due to compromising of the signing key. In [12], a new concept called intrusion-resilient signature was proposed to get rid of trusted time-stamping and certificate revocation services and a concrete scheme was presented. In this paper, we put forward a new scheme that can achieve the same effect in a much more efficient way. In our scheme, forward-secure signature serves as a building block that enables signature …

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Automatic Video Summarization By Graph Modeling, Chong-Wah Ngo, Yu-Fei Ma, Hong-Jiang Zhang Oct 2003

Automatic Video Summarization By Graph Modeling, Chong-Wah Ngo, Yu-Fei Ma, Hong-Jiang Zhang

Research Collection School Of Computing and Information Systems

We propose a unified approach for summarization based on the analysis of video structures and video highlights. Our approach emphasizes both the content balance and perceptual quality of a summary. Normalized cut algorithm is employed to globally and optimally partition a video into clusters. A motion attention model based on human perception is employed to compute the perceptual quality of shots and clusters. The clusters, together with the computed attention values, form a temporal graph similar to Markov chain that inherently describes the evolution and perceptual importance of video clusters. In our application, the flow of a temporal graph is …

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Making The Key Agreement Protocol In Mobile Ad Hoc Network More Efficient, Gang Yao, Kui Ren, Feng Bao, Robert H. Deng, Dengguo Feng Oct 2003

Making The Key Agreement Protocol In Mobile Ad Hoc Network More Efficient, Gang Yao, Kui Ren, Feng Bao, Robert H. Deng, Dengguo Feng

Research Collection School Of Computing and Information Systems

Mobile ad hoc networks offer convenient infrastructureless communications over the shared wireless channel. However, the nature of mobile ad hoc networks makes them vulnerable to security attacks, such as passive eavesdropping over the wireless channel and denial of service attacks by malicious nodes. To ensure the security, several cryptography protocols are implemented. Due to the resource scarcity in mobile ad hoc networks, the protocols must be communication efficient and need as less computational power as possible. Broadcast communication is an important operation for many application in mobile ad hoc networks. To securely broadcast a message, all the members in the …

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Variations Of Diffie-Hellman Problem, Feng Bao, Robert H. Deng, Huafei Zhu Oct 2003

Variations Of Diffie-Hellman Problem, Feng Bao, Robert H. Deng, Huafei Zhu

Research Collection School Of Computing and Information Systems

This paper studies various computational and decisional Diffie-Hellman problems by providing reductions among them in the high granularity setting. We show that all three variations of computational Diffie-Hellman problem: square Diffie-Hellman problem, inverse Diffie-Hellman problem and divisible Diffie-Hellman problem, are equivalent with optimal reduction. Also, we are considering variations of the decisional Diffie-Hellman problem in single sample and polynomial samples settings, and we are able to show that all variations are equivalent except for the argument DDH ⇐ SDDH. We are not able to prove or disprove this statement, thus leave an interesting open problem. Keywords: Diffie-Hellman problem, Square Diffie-Hellman …

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Moorean Absurdity And Conscious Belief, John N. Williams Oct 2003

Moorean Absurdity And Conscious Belief, John N. Williams

Research Collection School of Social Sciences

G. E. Moore observed that to for me to assert, “I went to the pictures last Tuesday but I don’t believe that I did” would be “absurd” (1942: 543). Over half a century later, the explanation of the nature of this absurdity remains problematic. Such assertions are unlike semantically odd Liar-type assertions such as “What I’m now saying is not true” since my Moorean assertion might be true: you may consistently imagine a situation in which I went to the pictures last Tuesday but fail to believe that I did. Moreover, if you contradict my assertion then your words, “If …

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Entrepreneurship And Social Endeavours In Singapore, Wee Liang Tan Oct 2003

Entrepreneurship And Social Endeavours In Singapore, Wee Liang Tan

Research Collection Lee Kong Chian School Of Business

Many people would confine entrepreneurship to the business arena and entrepreneurs to profit enterprises. In truth, entrepreneurship can extend to all aspects of human activity as defined by Raymond Kao as “the process of doing something new and/or different to create wealth for oneself and to add value to the society” (Kao, 1993). Apart from entrepreneurship that is solely “for profit” and in the business sphere, there is social entrepreneurship. Social entrepreneurship spans a continuum of community-based enterprises and entrepreneurial activities by volunteers for the good of their communities. It also includes philanthropic acts by successful individuals. While many may …

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Incorporating Diversification Into Risk Management, Mitchell Craig Warachka, A. Purnanandam, Y. Zhao, W.T. Ziemba Oct 2003

Incorporating Diversification Into Risk Management, Mitchell Craig Warachka, A. Purnanandam, Y. Zhao, W.T. Ziemba

Research Collection Lee Kong Chian School Of Business

No abstract provided.

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High-Performance Architectures For Ip-Based Multihop 802.11 Networks, Arup Acharya, Archan Misra, Sorav Bansal Oct 2003

High-Performance Architectures For Ip-Based Multihop 802.11 Networks, Arup Acharya, Archan Misra, Sorav Bansal

Research Collection School Of Computing and Information Systems

The concept of a forwarding node, which receives packets from upstream nodes and then transmits these packets to downstream nodes, is a key element of any multihop network, wired or wireless. While high-speed IP router architectures have been extensively studied for wired networks, the concept of a "wireless IP router" has not been addressed so far. We examine the limitations of the IEEE 802.11 MAC protocol in supporting a low-latency and high-throughput IP datapath comprising multiple wireless LAN hops. We first propose a wireless IP forwarding architecture that uses MPLS with modifications to 802.11 MAC to significantly improve packet forwarding …

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Adaptive Collusion Attack To A Block Oriented Watermarking Scheme, Yongdong Wu, Robert H. Deng Oct 2003

Adaptive Collusion Attack To A Block Oriented Watermarking Scheme, Yongdong Wu, Robert H. Deng

Research Collection School Of Computing and Information Systems

In this paper, we propose an adaptive collusion attack to a block oriented watermarking scheme [1]. In this attack, traitors conspire to selectively manipulate watermarked blocks to remove the watermark information. To this end, the traitors compare the watermarked blocks generated from the same original block. If two watermarked block are not equal, they average these two blocks to generate a pirated block. Then, replace the watermarked blocks with the pirated blocks so as to build a pirated image. The pirated image has no watermark but has much higher quality than watermarked images. We also give a theoretical analysis on …

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An Efficient Public-Key Framework, Jianying Zhou, Feng Bao, Robert H. Deng Oct 2003

An Efficient Public-Key Framework, Jianying Zhou, Feng Bao, Robert H. Deng

Research Collection School Of Computing and Information Systems

Public-key certificates play an important role in binding the public key with the identity of the owner of the corresponding private key. A certificate might be revoked before its scheduled expiry date by the issuing CA. Efficient and timely distribution of certificate revocation information is a big challenge facing the PKI providers. Existing certificate revocation schemes place a considerable processing, communication, and storage overheads on the CA as well as the relying parties. To improve the current situation, we propose a revocation-free public-key framework, in which the maximum lifetime of a certificate is divided into short periods and the certificate …

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Security Remarks On A Group Signature Scheme With Member Deletion, Guilin Wang, Feng Bao, Jianying Zhou, Robert H. Deng Oct 2003

Security Remarks On A Group Signature Scheme With Member Deletion, Guilin Wang, Feng Bao, Jianying Zhou, Robert H. Deng

Research Collection School Of Computing and Information Systems

A group signature scheme allows a group member of a given group to sign messages on behalf of the group in an anonymous and unlinkable fashion. In case of a dispute, however, a designated group manager can reveal the signer of a valid group signature. Based on the Camenisch-Michels group signature scheme, Kim, Lim and Lee proposed the first group signature scheme with a member deletion procedure at ICISC 2000. Their scheme is very efficient in both communication and computation aspects. Unfortunately, their scheme is insecure. In this paper, we first identify an effective way that allows any verifier to …

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Safe Robot Driving In Cluttered Environments, Chuck Thorpe, Justin Carlson, Dave Duggins, Jay Gowdy, Rob Maclachlan, Christoph Mertz, Arne Suppe, Bob Wang Oct 2003

Safe Robot Driving In Cluttered Environments, Chuck Thorpe, Justin Carlson, Dave Duggins, Jay Gowdy, Rob Maclachlan, Christoph Mertz, Arne Suppe, Bob Wang

Research Collection School Of Computing and Information Systems

The Navlab group at Carnegie Mellon University has a long history of development of automated vehicles and intelligent systems for driver assistance. The earlier work of the group concentrated on road following, cross-country driving, and obstacle detection. The new focus is on short-range sensing, to look all around the vehicle for safe driving. The current system uses video sensing, laser rangefinders, a novel light-stripe rangefinder, software to process each sensor individually, and a map-based fusion system. The complete system has been demonstrated on the Navlab 11 vehicle for monitoring the environment of a vehicle driving through a cluttered urban environment, …

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Wittgenstein, Moorean Absurdity And Its Disappearance From Speech, John N. Williams Oct 2003

Wittgenstein, Moorean Absurdity And Its Disappearance From Speech, John N. Williams

Research Collection School of Social Sciences

G. E. Moore famously observed that to say, "I went to the pictures last Tuesday but I don't believe that I did" would be "absurd." Why should it be absurd of me to say something about myself that might be true of me? Moore suggested an answer to this, but as I will show, one that fails. Wittgenstein was greatly impressed by Moore's discovery of a class of absurd but possibly true assertions because he saw that it illuminates "the logic of assertion". Wittgenstein suggests a promising relation of assertion to belief in terms of the idea that one "expresses …

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Moorean Absurdities And Iterated Beliefs, John N. Williams Oct 2003

Moorean Absurdities And Iterated Beliefs, John N. Williams

Research Collection School of Social Sciences

No abstract provided.

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An Efficient Known Plaintext Attack On Fea-M, Hongjun Wu, Feng Bao, Robert H. Deng Oct 2003

An Efficient Known Plaintext Attack On Fea-M, Hongjun Wu, Feng Bao, Robert H. Deng

Research Collection School Of Computing and Information Systems

Yi et al. have proposed a cipher called the fast encryption algorithm for multimedia (FEA-M). Recently Mihaljevi and Kohno pointed out that FEA-M is insecure. However, their attacks are not efficient: their chosen plaintext attack and known plaintext attack require 237-bit chosen plaintext and 260-bit known plaintext, respectively. In this paper we give an efficient known plaintext attack against FEA-M. Our attack requires only 228-bit known plaintext and about 233 XOR operations.

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Micro-Level Estimation Of The Prevalence Of Stunting And Underweight Among Children In Cambodia, Tomoki Fujii, Livia Montana Oct 2003

Micro-Level Estimation Of The Prevalence Of Stunting And Underweight Among Children In Cambodia, Tomoki Fujii, Livia Montana

Research Collection School Of Economics

We are pleased to share this copy of the preliminary report on "Micro-Level Estimation of the Prevalence of Stunting and Underweight Among Children in Cambodia." This study is the result of a collaboration between the Ministry of Planning, the United Nations World Food Programme and the MEASURE DHS+ project, with in-kind assistance from The World Bank. We also would like to express our acknowledgement to Italian Cooperation and International Fund for Agricultural Development for supporting in publication and distribution.

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Multi-Agent Coalition Via Autonomous Price Negotiation In A Real-Time Web Environment, Hoong Chuin Lau, Wei Sian Lim Oct 2003

Multi-Agent Coalition Via Autonomous Price Negotiation In A Real-Time Web Environment, Hoong Chuin Lau, Wei Sian Lim

Research Collection School Of Computing and Information Systems

In e-marketplaces, customers specify job requests in real-time and agents form coalitions to service them. This paper proposes a protocol for self-interested agents to negotiate prices in forming successful coalitions. We propose and experiment with two negotiation schemes: one allows information sharing while the other does not.

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A Formal Test Of Density Forecast Evaluation, Anil K. Bera, Aurobindo Ghosh Oct 2003

A Formal Test Of Density Forecast Evaluation, Anil K. Bera, Aurobindo Ghosh

Research Collection School Of Economics

Recent econometricians have shifted their attention from point and interval forecasts of the probability density functions (PDF) of various market variables. One of the main problems in this area has been evaluation of the density forecasts. In this papers, we propose a formal test for density forecast evaluation using Neyman (1937) smooth test procedure. Apart from giving indications of acceptance or rejection of the tested model, this approach provides specific sources (such as the mean, variance, skewness and kurtosis or the location, scale and shape of the distribution) or rejections, thereby helping in deciding possible modifications of the assumed model. …

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Part Ii - What Would You Do - With A Taniwha At The Table?, Ian Macduff Oct 2003

Part Ii - What Would You Do - With A Taniwha At The Table?, Ian Macduff

Research Collection Yong Pung How School Of Law

In the last issues of Negotiation Journal, the author explored the complicating factor of having a taniwha or spirit at the negotiating table in a New Zeland case. He challenged his readers to give him suggestions about how negotiators might grapple with often preplexing problems posed by the spiritual valus of their counterparts.

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