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Research Collection School Of Computing and Information Systems

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Articles 5611 - 5640 of 6891

Full-Text Articles in Physical Sciences and Mathematics

Probabilistic Public Key Encryption With Equality Test, Guomin Yang, Chik How Tan, Qiong Huang, Duncan S. Wong Mar 2010

Probabilistic Public Key Encryption With Equality Test, Guomin Yang, Chik How Tan, Qiong Huang, Duncan S. Wong

Research Collection School Of Computing and Information Systems

We present a (probabilistic) public key encryption (PKE) scheme such that when being implemented in a bilinear group, anyone is able to check whether two ciphertexts are encryptions of the same message. Interestingly, bilinear map operations are not required in key generation, encryption or decryption procedures of the PKE scheme, but is only required when people want to do an equality test (on the encrypted messages) between two ciphertexts that may be generated using different public keys. We show that our PKE scheme can be used in different applications such as searchable encryption and partitioning encrypted data. Moreover, we show …


Twitterrank: Finding Topic-Sensitive Influential Twitterers, Jianshu Weng, Ee Peng Lim, Jing Jiang, Qi He Feb 2010

Twitterrank: Finding Topic-Sensitive Influential Twitterers, Jianshu Weng, Ee Peng Lim, Jing Jiang, Qi He

Research Collection School Of Computing and Information Systems

This paper focuses on the problem of identifying influential users of micro-blogging services. Twitter, one of the most notable micro-blogging services, employs a social-networking model called "following", in which each user can choose who she wants to "follow" to receive tweets from without requiring the latter to give permission first. In a dataset prepared for this study, it is observed that (1) 72.4% of the users in Twitter follow more than 80% of their followers, and (2) 80.5% of the users have 80% of users they are following follow them back. Our study reveals that the presence of "reciprocity" can …


Further Exploration On Relationship Between Crisp Sets And Fuzzy Sets, Zhaoxia Wang, Quan Wang, Ming Bai, Chen Zeng-Qiang, Zhen Sun Feb 2010

Further Exploration On Relationship Between Crisp Sets And Fuzzy Sets, Zhaoxia Wang, Quan Wang, Ming Bai, Chen Zeng-Qiang, Zhen Sun

Research Collection School Of Computing and Information Systems

This paper employs the concept of fuzzify upgrade operator to describe the relationship between crisp sets, fuzzy sets and higher order fuzzy sets, such as type-2 fuzzy sets. Theory analysis and case studies demonstrate that a crisp set can be represented by a type-1 fuzzy set, a type-1 fuzzy set can be represented by a type-2 fuzzy set, and a type-n (n>=2) fuzzy set can be represented by a type-(n+1) (n>=2) fuzzy set. The fuzzify upgrade operator makes crisp sets, type-1 fuzzy sets, type-2 fuzzy sets and any fuzzy sets much more accessible to all readers. The relationship …


Player Performance Prediction In Massively Multiplayer Online Role-Playing Games (Mmorpgs), Kyong Jin Shim, Richa Sharan, Jaideep Srivastava Feb 2010

Player Performance Prediction In Massively Multiplayer Online Role-Playing Games (Mmorpgs), Kyong Jin Shim, Richa Sharan, Jaideep Srivastava

Research Collection School Of Computing and Information Systems

Recent years have seen an ever increasing number of people interacting in the online space. Massively multiplayer online role-playing games (MMORPGs) are personal computer or console-based digital games where thousands of players can simultaneously sign on to the same online, persistent virtual world to interact and collaborate with each other through their in-game characters. In recent years, researchers have found virtual environments to be a sound venue for studying learning, collaboration, social participation, literacy in online space, and learning trajectory at the individual level as well as at the group level. While many games today provide web and GUI-based reports …


Estimating The Quality Of Postings In The Real-Time Web, Hady W. Lauw, Alexandros Ntoulas, Krishnaram Kenthapadi Feb 2010

Estimating The Quality Of Postings In The Real-Time Web, Hady W. Lauw, Alexandros Ntoulas, Krishnaram Kenthapadi

Research Collection School Of Computing and Information Systems

Millions of users are posting their status updates, interesting findings, news, ideas and observations in real-time on microblogging services such as Twitter, Jaiku and Plurk. This real-time Web can be a great resource of valuable timely information. Since the real-time Web is completely open and decentralized and anyone may post information at whim, distinguishing interesting and popular postings from the mundane ones is a challenging task. In this paper we study the problem of estimating the quality (or “interestingness”) of postings in the real-time Web. We identify several important factors that are indicative of the quality of postings, and present …


An Analysis Of Extreme Price Shocks And Illiquidity Among Trend Followers, Bernard Lee, Shih-Fen Cheng, Annie Koh Feb 2010

An Analysis Of Extreme Price Shocks And Illiquidity Among Trend Followers, Bernard Lee, Shih-Fen Cheng, Annie Koh

Research Collection School Of Computing and Information Systems

We construct an agent-based model to study the interplay between extreme price shocks and illiquidity in the presence of systematic traders known as trend followers. The agent-based approach is particularly attractive in modeling commodity markets because the approach allows for the explicit modeling of production, capacities, and storage constraints. Our study begins by using the price stream from a market simulation involving human participants and studies the behavior of various trend-following strategies, assuming initially that their participation will not impact the market. We notice an incremental deterioration in strategy performance as and when strategies deviate further and further from the …


Efficient Valid Scope For Location-Dependent Spatial Queries In Mobile Environments, Ken C. K. Lee, Wang-Chien Lee, Hong Va Leong, Brandon Unger, Baihua Zheng Feb 2010

Efficient Valid Scope For Location-Dependent Spatial Queries In Mobile Environments, Ken C. K. Lee, Wang-Chien Lee, Hong Va Leong, Brandon Unger, Baihua Zheng

Research Collection School Of Computing and Information Systems

In mobile environments, mobile clients can access information with respect to their locations by submitting Location-Dependent Spatial Queries (LDSQs) to Location-Based Service (LBS) servers. Owing to scarce wireless channel bandwidth and limited client battery life, frequent LDSQ submission from clients must be avoided. Observing that LDSQs issued from a client located at nearby positions would likely return the same query results, we explore the idea of valid scope, which represents a spatial area in which a set of LDSQs will retrieve exactly the same set of query results. With a valid scope derived and an LDSQ result cached, a client …


Privacy-Preserving Similarity-Based Text Retrieval, Hwee Hwa Pang, Jialie Shen, Ramayya Krishnan Feb 2010

Privacy-Preserving Similarity-Based Text Retrieval, Hwee Hwa Pang, Jialie Shen, Ramayya Krishnan

Research Collection School Of Computing and Information Systems

Users of online services are increasingly wary that their activities could disclose confidential information on their business or personal activities. It would be desirable for an online document service to perform text retrieval for users, while protecting the privacy of their activities. In this article, we introduce a privacy-preserving, similarity-based text retrieval scheme that (a) prevents the server from accurately reconstructing the term composition of queries and documents, and (b) anonymizes the search results from unauthorized observers. At the same time, our scheme preserves the relevance-ranking of the search server, and enables accounting of the number of documents that each …


Applying Soft Cluster Analysis Techniques To Customer Interaction Information, Randall E. Duran, Li Zhang, Tom Hayhurst Jan 2010

Applying Soft Cluster Analysis Techniques To Customer Interaction Information, Randall E. Duran, Li Zhang, Tom Hayhurst

Research Collection School Of Computing and Information Systems

The number of channels available for companies and customers to communicate with one another has increased dramatically over the past several decades. Although some market segmentation efforts utilize high-level customer interaction statistics, in-depth information regarding customers’ use of different communication channels is often ignored. Detailed customer interaction information can help companies improve the way that they market to customers by taking into consideration customers’ behaviour patterns and preferences. However, a key challenge of interpreting customer contact information is that many channels have only been in existence for a relatively short period of time, and thus, there is limited understanding and …


Trust-Oriented Composite Service Selection With Qos Constraints, Lei Li, Yang Wang, Ee Peng Lim Jan 2010

Trust-Oriented Composite Service Selection With Qos Constraints, Lei Li, Yang Wang, Ee Peng Lim

Research Collection School Of Computing and Information Systems

In Service-Oriented Computing (SOC) environments, service clients interact with service providers for consuming services. From the viewpoint of service clients, the trust level of a service or a service provider is a critical factor to consider in service selection, particularlywhen a client is looking for a service from a large set of services or service providers. However, a invoked service may be composed of other services. The complex invocations in composite services greatly increase the complexity of trust-oriented service selection. In this paper, we propose novel approaches for composite service representation, trust evaluation and trust-oriented com-posite service selection (with QoS …


A Boosting Framework For Visuality-Preserving Distance Metric Learning And Its Application To Medical Image Retrieval, Yang Liu, Rong Jin, Lily Mummert, Rahul Sukthankar, Adam Goode, Bin Zheng, Steven C. H. Hoi, Mahadev Satyanarayanan Jan 2010

A Boosting Framework For Visuality-Preserving Distance Metric Learning And Its Application To Medical Image Retrieval, Yang Liu, Rong Jin, Lily Mummert, Rahul Sukthankar, Adam Goode, Bin Zheng, Steven C. H. Hoi, Mahadev Satyanarayanan

Research Collection School Of Computing and Information Systems

Similarity measurement is a critical component in content-based image retrieval systems, and learning a good distance metric can significantly improve retrieval performance. However, despite extensive study, there are several major shortcomings with the existing approaches for distance metric learning that can significantly affect their application to medical image retrieval. In particular, "similarity" can mean very different things in image retrieval: resemblance in visual appearance (e.g., two images that look like one another) or similarity in semantic annotation (e.g., two images of tumors that look quite different yet are both malignant). Current approaches for distance metric learning typically address only one …


Motivated Learning As An Extension Of Reinforcement Learning, Janusz Starzyk, Pawel Raif, Ah-Hwee Tan Jan 2010

Motivated Learning As An Extension Of Reinforcement Learning, Janusz Starzyk, Pawel Raif, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

We have developed a unified framework to conduct computational experiments with both learning systems: Motivated learning based on Goal Creation System, and reinforcedment learning using RL Q-Learning Algorithm. Future work includes combining motivated learning to set abstract motivations and manage goals with reinforcement learning to learn proper actions. This will allow testing of motivated learning on typical reinforcement learning benchmarks with large dimensionality of the state/action spaces.


Wikipedia2onto: Building Concept Ontology Automatically, Experimenting With Web Image Retrieval, Huan Wang, Xing Jiang, Liang-Tien Chia, Ah-Hwee Tan Jan 2010

Wikipedia2onto: Building Concept Ontology Automatically, Experimenting With Web Image Retrieval, Huan Wang, Xing Jiang, Liang-Tien Chia, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

Given its effectiveness to better understand data, ontology has been used in various domains including artificial intelligence, biomedical informatics and library science. What we have tried to promote is the use of ontology to better understand media (in particular, images) on the World Wide Web. This paper describes our preliminary attempt to construct a large-scale multi-modality ontology, called AutoMMOnto, for web image classification. Particularly, to enable the automation of text ontology construction, we take advantage of both structural and content features of Wikipedia and formalize real world objects in terms of concepts and relationships. For visual part, we train classifiers …


A Review Of The Professionalization Of The Software Industry: Has It Made Software Engineering A Real Profession?, Heng Ngee Mok Jan 2010

A Review Of The Professionalization Of The Software Industry: Has It Made Software Engineering A Real Profession?, Heng Ngee Mok

Research Collection School Of Computing and Information Systems

Every industry strives to be called a "profession", and software engineering is no exception. This paper attempts to define "profession" from three different perspectives and provides a chronological narration of the professionalization efforts of major IT bodies such as the IEEE Computer Society, Association of Computing Machinery and British Computer Society to promote software engineering from "occupation" to "profession". The outcome of this professionalization process is then examined against the three vastly different definitions of "profession" to qualitatively gauge the success of the professionalization process.


Does Co-Opetition Change The Game? A Bayesian Analysis Of Participation Strategy In An Industry Standard-Setting Organization, Robert J. Kauffman, Benjamin B. M. Shao, Juliana Y. Tsai Jan 2010

Does Co-Opetition Change The Game? A Bayesian Analysis Of Participation Strategy In An Industry Standard-Setting Organization, Robert J. Kauffman, Benjamin B. M. Shao, Juliana Y. Tsai

Research Collection School Of Computing and Information Systems

Across different industries, we observe the emergence of industry standard-setting organizations (SSO) that focus on the creation of industry-specific process standards. Firms adopt a strategy of co-opetition, the combination of cooperation and competition, during standards development. We propose that a firm's co-opetition strategy is revealed to some extent by when it elects to participate in an industry SSO. Bayesian information updating offers an effective empirical modeling perspective for studying firms' participation strategies when managers' beliefs and uncertainties are factored into their decision-making. We analyze a panel data set of 73 U.S. public firms over a 20-year period. These firms are …


Modeling Anticipatory Event Transitions, He Qi, Kuiyu Chang, Ee Peng Lim Jan 2010

Modeling Anticipatory Event Transitions, He Qi, Kuiyu Chang, Ee Peng Lim

Research Collection School Of Computing and Information Systems

Major world events such as terrorist attacks, natural disasters, wars, etc. typically progress through various representative stages/states in time. For example, a volcano eruption could lead to earthquakes, tsunamis, aftershocks, evacuation, rescue efforts, international relief support, rebuilding, and resettlement, etc. By analyzing various types of catastrophical and historical events, we can derive corresponding event transition models to embed useful information at each state. The knowledge embedded in these models can be extremely valuable. For instance, a transition model of the 1918-1920 flu pandemic could be used for the planning and allocation of resources to decisively respond to future occurrences of …


Remote Attestation On Function Execution, Liang Gu, Yueqiang Cheng, Xuhua Ding, Robert H. Deng, Yao Guo, Weizhong Shao Jan 2010

Remote Attestation On Function Execution, Liang Gu, Yueqiang Cheng, Xuhua Ding, Robert H. Deng, Yao Guo, Weizhong Shao

Research Collection School Of Computing and Information Systems

Remote attestation provides the basis for one platform to establish trusts on another. In this paper, we consider the problem of attesting the correctness of program executions. We propose to measure the target program and all the objects it depends on, with an assumption that the Secure Kernel and the Trusted Platform Module provide a secure execution environment through process separation. The attestation of the target program begins with a program analysis on the source code or the binary code in order to find out the relevant executables and data objects. Whenever such a data object is accessed or a …


Introducing Communication In Dis-Pomdps With Locality Of Interaction, Makoto Tasaki, Yuichi Yabu, Yuki Iwanari, Makoto Yokoo, Janusz Marecki, Pradeep Reddy Varakantham, Milind Tambe Jan 2010

Introducing Communication In Dis-Pomdps With Locality Of Interaction, Makoto Tasaki, Yuichi Yabu, Yuki Iwanari, Makoto Yokoo, Janusz Marecki, Pradeep Reddy Varakantham, Milind Tambe

Research Collection School Of Computing and Information Systems

The Networked Distributed POMDPs (ND-POMDPs) can model multiagent systems in uncertain domains and has begun to scale-up the number of agents. However, prior work in ND-POMDPs has failed to address communication. Without communication, the size of a local policy at each agent within the ND-POMDPs grows exponentially in the time horizon. To overcome this problem, we extend existing algorithms so that agents periodically communicate their observation and action histories with each other. After communication, agents can start from new synchronized belief state. Thus, we can avoid the exponential growth in the size of local policies at agents. Furthermore, we introduce …


On The Potential Of Limitation-Oriented Malware Detection And Prevention Techniques On Mobile Phones, Qiang Yan, Robert H. Deng, Yingjiu Li, Tieyan Li Jan 2010

On The Potential Of Limitation-Oriented Malware Detection And Prevention Techniques On Mobile Phones, Qiang Yan, Robert H. Deng, Yingjiu Li, Tieyan Li

Research Collection School Of Computing and Information Systems

The malware threat for mobile phones is expected to increase with the functionality enhancement of mobile phones. This threat is exacerbated with the surge in population of smart phones instilled with stable Internet access which provides attractive targets for malware developers. Prior research on malware protection has focused on avoiding the negative impact of the functionality limitations of mobile phones to keep the performance cost within the limitations of mobile phones. Being different, this paper investigates the positive impact of these limitations on suppressing the development of mobile malware. We study the state-of-the-art mobile malware, as well as the progress …


Crctol: A Semantic Based Domain Ontology Learning System, Xing Jiang, Ah-Hwee Tan Jan 2010

Crctol: A Semantic Based Domain Ontology Learning System, Xing Jiang, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

Domain ontologies play an important role in supporting knowledge‐based applications in the Semantic Web. To facilitate the building of ontologies, text mining techniques have been used to perform ontology learning from texts. However, traditional systems employ shallow natural language processing techniques and focus only on concept and taxonomic relation extraction. In this paper we present a system, known as Concept‐Relation‐Concept Tuple‐based Ontology Learning (CRCTOL), for mining ontologies automatically from domain‐specific documents. Specifically, CRCTOL adopts a full text parsing technique and employs a combination of statistical and lexico‐syntactic methods, including a statistical algorithm that extracts key concepts from a document collection, …


Universal Authentication Protocols For Anonymous Wireless Communications, Guomin Yang, Qiong Huang, Duncan S. Wong, Xiaotie Deng Jan 2010

Universal Authentication Protocols For Anonymous Wireless Communications, Guomin Yang, Qiong Huang, Duncan S. Wong, Xiaotie Deng

Research Collection School Of Computing and Information Systems

A secure roaming protocol allows a roaming user U to visit a foreign server V and establish a session key in an authenticated way such that U authenticates V and at the same time convinces V that it is a legitimate subscriber of some server H, called the home server of U. The conventional approach requires the involvement of all the three parties. In this paper, we propose a new approach which requires only two parties, U and V, to get involved. We propose two protocols: one provides better efficiency and supports user anonymity to an extent comparable to that …


Representations Of Keypoint-Based Semantic Concept Detection: A Comprehensive Study, Yu-Gang Jiang, Jun Yang, Chong-Wah Ngo Jan 2010

Representations Of Keypoint-Based Semantic Concept Detection: A Comprehensive Study, Yu-Gang Jiang, Jun Yang, Chong-Wah Ngo

Research Collection School Of Computing and Information Systems

Based on the local keypoints extracted as salient image patches, an image can be described as a "bag-of-visual-words (BoW)" and this representation has appeared promising for object and scene classification. The performance of BoW features in semantic concept detection for large-scale multimedia databases is subject to various representation choices. In this paper, we conduct a comprehensive study on the representation choices of BoW, including vocabulary size, weighting scheme, stop word removal, feature selection, spatial information, and visual bi-gram. We offer practical insights in how to optimize the performance of BoW by choosing appropriate representation choices. For the weighting scheme, we …


An Empirical Analysis Of Mobile Voice Service And Sms: A Structural Model, Youngsoo Kim, Rahul Telang, William B. Vogt, Ramayya Krishnan Jan 2010

An Empirical Analysis Of Mobile Voice Service And Sms: A Structural Model, Youngsoo Kim, Rahul Telang, William B. Vogt, Ramayya Krishnan

Research Collection School Of Computing and Information Systems

In addition to the wireless telephony boom, a similar exponentially increasing trend in wireless data service—for example, short message service (SMS)—is visible as technology advances. We develop a structural model to examine user demand for voice service and SMS. Specifically, we measure the own- and cross-price elasticities of these services. The cross-price elasticity is of significant importance because marketing activities are critically influenced by whether the goods are substitutes or complements. The research context poses significant econometric challenges due to three-part tariffs and sequential discrete plan choice and continuous quantity choice decisions. Using detailed individual consumption data of more than …


Keep It Simple With Time: A Reexamination Of Probabilistic Topic Detection Models, Qi He, Kuiyu Chang, Ee Peng Lim, Arindam Banerjee Jan 2010

Keep It Simple With Time: A Reexamination Of Probabilistic Topic Detection Models, Qi He, Kuiyu Chang, Ee Peng Lim, Arindam Banerjee

Research Collection School Of Computing and Information Systems

Topic detection (TD) is a fundamental research issue in the Topic Detection and Tracking (TDT) community with practical implications; TD helps analysts to separate the wheat from the chaff among the thousands of incoming news streams. In this paper, we propose a simple and effective topic detection model called the temporal Discriminative Probabilistic Model (DPM), which is shown to be theoretically equivalent to the classic vector space model with feature selection and temporally discriminative weights. We compare DPM to its various probabilistic cousins, ranging from mixture models like von-Mises Fisher (vMF) to mixed membership models like Latent Dirichlet Allocation (LDA). …


Vulnerability Analysis Of Rfid Protocols For Tag Ownership Transfer, Pedro Peris-Lopez, Julio Hernandez-Castro, Juan Tapiador, Tieyan Li, Yingjiu Li Jan 2010

Vulnerability Analysis Of Rfid Protocols For Tag Ownership Transfer, Pedro Peris-Lopez, Julio Hernandez-Castro, Juan Tapiador, Tieyan Li, Yingjiu Li

Research Collection School Of Computing and Information Systems

In RFIDSec’08, Song proposed an ownership transfer scheme, which consists of an ownership transfer protocol and a secret update protocol [7]. The ownership transfer protocol is completely based on a mutual authentication protocol proposed in WiSec’08 [8]. In Rizomiliotis et al. (2009) [6], van Deursen and Radomirovic (2008), the first weaknesses to be identified (tag and server impersonation) were addressed and this paper completes the consideration of them all. We find that the mutual authentication protocol, and therefore the ownership transfer protocol, possesses certain weaknesses related to most of the security properties initially required in protocol design: tag information leakage, …


Information Integration For Graph Databases, Ee Peng Lim, Aixin Sun, Anwitaman Datta, Chang Kuiyu Jan 2010

Information Integration For Graph Databases, Ee Peng Lim, Aixin Sun, Anwitaman Datta, Chang Kuiyu

Research Collection School Of Computing and Information Systems

With increasing interest in querying and analyzing graph data from multiple sources, algorithms and tools to integrate different graphs become very important. Integration of graphs can take place at the schema and instance levels. While links among graph nodes pose additional challenges to graph information integration, they can also serve as useful features for matching nodes representing real-world entities. This chapter introduces a general framework to perform graph information integration. It then gives an overview of the state-of-the-art research and tools in graph information integration.


Dual Phase Learning For Large Scale Video Gait Recognition, Jialie Shen, Hwee Hwa Pang, Dacheng Tao, Xuelong Li Jan 2010

Dual Phase Learning For Large Scale Video Gait Recognition, Jialie Shen, Hwee Hwa Pang, Dacheng Tao, Xuelong Li

Research Collection School Of Computing and Information Systems

Accurate gait recognition from video is a complex process involving heterogenous features, and is still being developed actively. This article introduces a novel framework, called GC2F, for effective and efficient gait recognition and classification. Adopting a ”refinement-and-classification” principle, the framework comprises two components: 1) a classifier to generate advanced probabilistic features from low level gait parameters; and 2) a hidden classifier layer (based on multilayer perceptron neural network) to model the statistical properties of different subject classes. To validate our framework, we have conducted comprehensive experiments with a large test collection, and observed significant improvements in identification accuracy relative to …


Do Online Reviews Reflect A Product's True Perceived Quality? An Investigation Of Online Movie Reviews Across Cultures, Noi Sian Koh, Nan Hu, Eric K. Clemons Jan 2010

Do Online Reviews Reflect A Product's True Perceived Quality? An Investigation Of Online Movie Reviews Across Cultures, Noi Sian Koh, Nan Hu, Eric K. Clemons

Research Collection School Of Computing and Information Systems

When does the reported average of online ratings match perceived average assessment? We apply behavioral theory to capture intentions in rating online movie reviews in two dissimilar countries - China and the United States. We argue that consumers' rating behaviors are affected by cultural influences. Based on data collected from imdb.com and douban.com, we found significant differences across raters from these two different cultures. Additionally, we examined how cultural elements influence rating behavior for a hybrid culture - Singapore. Under-reporting bias occurs when consumers with extreme opinions are more likely to report their opinions than consumers with moderate reviews, resulting …


Periodic Resource Reallocation In Two-Echelon Repairable Item Inventory Systems, Hoong Chuin Lau, Jie Pan, Huawei Song Jan 2010

Periodic Resource Reallocation In Two-Echelon Repairable Item Inventory Systems, Hoong Chuin Lau, Jie Pan, Huawei Song

Research Collection School Of Computing and Information Systems

Given an existing stock allocation in an inventory system, it is often necessary to perform reallocation over multiple time points to address inventory imbalance and maximize availability. In this paper, we focus on the situation where there are two opportunities to perform reallocation within a replenishment cycle. We derive a mathematical model to determine when and how to perform reallocation. Furthermore, we consider the extension of this model to the situation allowing an arbitrary number of reallocations. Experimental results show that the two-reallocation approach achieves better performance compared with the single-reallocation approach found in the literature. We also illustrate how …


Teleoph: A Secure Real-Time Teleophthalmology System, Yongdong Wu, Zhou Wei, Haixia Yao, Zhigang Zhao, Lek Heng Ngoh, Robert H. Deng, Shengsheng Yu Jan 2010

Teleoph: A Secure Real-Time Teleophthalmology System, Yongdong Wu, Zhou Wei, Haixia Yao, Zhigang Zhao, Lek Heng Ngoh, Robert H. Deng, Shengsheng Yu

Research Collection School Of Computing and Information Systems

Teleophthalmology (TeleOph) is an electronic counterpart of today's face-to-face, patient-to-specialist ophthalmology system. It enables one or more ophthalmologists to remotely examine a patient's condition via a confidential and authentic communication channel. Specifically, TeleOph allows a trained nonspecialist in a primary clinic to screen the patients with digital instruments (e.g., camera, ophthalmoscope). The acquired medical data are delivered to the hospital where an ophthalmologist will review the data collected and, if required, provide further consultation for the patient through a real-time secure channel established over a public Internet network. If necessary, the ophthalmologist is able to further sample the images/video of …