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Articles 8641 - 8670 of 9003

Full-Text Articles in Computer Sciences

Enhancing Profiles For Anomaly Detection Using Time Granularities, Yingjiu Li, Ningning Wu, X. Sean Wang, Sushil Jajodia Jan 2002

Enhancing Profiles For Anomaly Detection Using Time Granularities, Yingjiu Li, Ningning Wu, X. Sean Wang, Sushil Jajodia

Research Collection School Of Computing and Information Systems

Recently, association rules have been used to generate profiles of normal behavior for anomaly detection. However, the time factor (especially in terms of multiple time granularities) has not been utilized extensively in generation of these profiles. In reality, user behavior during different time intervals may be very different. For example, the normal number and duration of FTP connections may vary from working hours to midnight, from business day to weekend or holiday. Furthermore, these variations may depend on the day of the month or the week. This paper proposes to build profiles using temporal association rules in terms of multiple …


Knowledge Management Mechanisms In E-Commerce: A Study Of Online Retailing And Auction Sites, Fiona Fui-Hoon Nah, Keng Siau, Yuhong Tian, Min Ling Jan 2002

Knowledge Management Mechanisms In E-Commerce: A Study Of Online Retailing And Auction Sites, Fiona Fui-Hoon Nah, Keng Siau, Yuhong Tian, Min Ling

Research Collection School Of Computing and Information Systems

Knowledge management is vital to a company's success in this e-commerce era. Not only has the topic of knowledge management attracted much research attention lately, but the management of customer knowledge is also becoming increasingly important. Despite its significance, few research studies have systematically investigated knowledge management in the e-commerce context. None of the studies we reviewed looked at how knowledge management mechanisms were employed in e-commerce. This research presents a comprehensive analysis of the knowledge management mechanisms employed by 14 e-commerce sites that were rated as being the best by Gomez.com, an independent Internet quality measurement firm. Specifically, we …


Community Banking In The E-Business Era, Peter Southard, Keng Siau Jan 2002

Community Banking In The E-Business Era, Peter Southard, Keng Siau

Research Collection School Of Computing and Information Systems

This paper reviews how existing and potential uses of Internet technology can generate a competitive advantage for rural community banks. To do so, it offers a framework for analyzing Internet technology investment decisions. Organizations in this segment of the banking industry are often more removed from centers of technology and have traditionally been more conservative in their approaches to information technology (among other things). Banking Associations have developed in the U.S., such as the Independent Bankers Association, to try and help community banks coordinate marketing, legislative, and other issues that they have in common. The use of Internet technology can …


Enabling Technologies For E-Commerce And Erp Integration, Keng Siau, Jake Messersmith Jan 2002

Enabling Technologies For E-Commerce And Erp Integration, Keng Siau, Jake Messersmith

Research Collection School Of Computing and Information Systems

Focuses on a study which analyzed the enabling technologies for integrating Enterprise Resource Planning (ERP) and e-business. Difficulties in integrating ERP and e-business; Architecture supporting ERP and e-commerce; Model for integrating ERP and e-business.


Using Real Options Analysis For Evaluating Uncertain Investments In Information Technology: Insights From The Icis 2001 Debate, Paul P. Tallon, Robert J. Kauffman, Henry C. Lucas, Andrew B. Whinston, Kevin Zhu Jan 2002

Using Real Options Analysis For Evaluating Uncertain Investments In Information Technology: Insights From The Icis 2001 Debate, Paul P. Tallon, Robert J. Kauffman, Henry C. Lucas, Andrew B. Whinston, Kevin Zhu

Research Collection School Of Computing and Information Systems

Business and information systems (IS) executives continue to grapple with issues of risk and uncertainty in evaluating investments in information technology (IT). Despite the use of net present value (NPV) and other investment appraisal techniques, executives are often forced to rely on instinct when finalizing IT investment decisions. Recognizing the shortcomings of NPV, real options analysis has been suggested as an alternative approach, one that considers the risks associated with an investment while recognizing the ability of corporations to defer an investment until a later period or to make a partial investment instead. Responding to a growing interest in real …


Component-Based Development Using Uml, L. Zhao, Keng Siau Jan 2002

Component-Based Development Using Uml, L. Zhao, Keng Siau

Research Collection School Of Computing and Information Systems

Component-based software development (CBD) is a potential breakthrough for software engineering. Unified Modeling Language (UML) can potentially facilitate CBD design and modeling. Although many research projects concentrate on the conceptual interrelation of UML and CBD, few incorporate actual component frameworks into the discussion, which is critical for real-world software system design and modeling. This paper reviews component-based development, including the use of UML for modeling CBD. The paper then discusses the means by which UML extension mechanisms can be used to better support the popular component framework -- CORBA. Two other important component frameworks, DCOM and Web Services, are also …


Acceptable Internet Use Policy, Keng Siau, Fiona Fui-Hoon Nah, Limei Teng Jan 2002

Acceptable Internet Use Policy, Keng Siau, Fiona Fui-Hoon Nah, Limei Teng

Research Collection School Of Computing and Information Systems

Surveying use policies of three organizations--- educational institutions, ISPs, and non-ISPs.


Characteristics Of Erp Software Maintenance: A Multiple Case Study, Fiona Fui-Hoon Nah, Silvana Faja, Teuta Cata Dec 2001

Characteristics Of Erp Software Maintenance: A Multiple Case Study, Fiona Fui-Hoon Nah, Silvana Faja, Teuta Cata

Research Collection School Of Computing and Information Systems

A multiple case study approach was employed to identify maintenance activities pertaining to enterprise resource planning (ERP) implementation, classify them into maintenance categories, and assess their relative frequency at various stages of the ERP maintenance lifecycle. Five maintenance categories (corrective, adaptive, perfective, preventive, user support) were identified from a review of the literature on software maintenance. A new category pertaining to ‘communication, coordination and knowledge exchange with external parties’ and herein labeled ‘external parties’ is introduced to highlight the supporting role of external parties in ERP maintenance. This category includes reporting problems to vendors and consultants, tracking their progress towards …


Automated Online News Classification With Personalization, Chee-Hong Chan, Aixin Sun, Ee Peng Lim Dec 2001

Automated Online News Classification With Personalization, Chee-Hong Chan, Aixin Sun, Ee Peng Lim

Research Collection School Of Computing and Information Systems

Classification of online news, in the past, has often been done manually. In our proposed Categorizor system, we have experimented an automated approach to classify online news using the Support Vector Machine (SVM). SVM has been shown to deliver good classification results when ample training documents are given. In our research, we have applied SVM to personalized classification of online news.


Pickup And Delivery Problem With Time Windows: Algorithms And Test Case Generation, Hoong Chuin Lau, Zhe Liang Nov 2001

Pickup And Delivery Problem With Time Windows: Algorithms And Test Case Generation, Hoong Chuin Lau, Zhe Liang

Research Collection School Of Computing and Information Systems

In the pickup and delivery problem with time windows (PDPTW), vehicles have to transport loads from origins to destinations respecting capacity and time constraints. In this paper, we present a two-phase method to solve the PDPTW. In the first phase, we apply a novel construction heuristics to generate an initial solution. In the second phase, a tabu search method is proposed to improve the solution. Another contribution of this paper is a strategy to generate good problem instances and benchmarking solutions for PDPTW, based on Solomon's benchmark test cases for VRPTW. Experimental results show that our approach yields very good …


Hierarchical Text Classification And Evaluation, Aixin Sun, Ee Peng Lim Nov 2001

Hierarchical Text Classification And Evaluation, Aixin Sun, Ee Peng Lim

Research Collection School Of Computing and Information Systems

Hierarchical Classification refers to assigning of one or more suitable categories from a hierarchical category space to a document. While previous work in hierarchical classification focused on virtual category trees where documents are assigned only to the leaf categories, we propose atop-down level-based classification method that can classify documents to both leaf and internal categories. As the standard performance measures assume independence between categories, they have not considered the documents incorrectly classified into categories that are similar or not far from the correct ones in the category tree. We therefore propose the Category-Similarity Measures and Distance-Based Measures to consider the …


Privacy Protection For Transactions Of Digital Goods, Feng Bao, Robert H. Deng Nov 2001

Privacy Protection For Transactions Of Digital Goods, Feng Bao, Robert H. Deng

Research Collection School Of Computing and Information Systems

In this paper we study the problem of how to protect users’ privacy in web transactions of digital goods. In particular, we introduce a system which allows a user to disclose his/her identity information (such as user account or credit card number) to a web site in exchange for a digital item, but prevents the web site from learning which specific item the user intends to obtain. The problem concerned here is orthogonal to the problem of anonymous transactions [RSG98], [RR98] but commensurate with the general problem of PIR (private information retrieval) [CGK95]


A Review Of Data Mining Techniques, Sang Jun Lee, Keng Siau Oct 2001

A Review Of Data Mining Techniques, Sang Jun Lee, Keng Siau

Research Collection School Of Computing and Information Systems

Terabytes of data are generated everyday in many organizations. To extract hidden predictive information from large volumes of data, data mining (DM) techniques are needed. Organizations are starting to realize the importance of data mining in their strategic planning and successful application of DM techniques can be an enormous payoff for the organizations. This paper discusses the requirements and challenges of DM, and describes major DM techniques such as statistics, artificial intelligence, decision tree approach, genetic algorithm, and visualization.


On Clustering And Retrieval Of Video Shots, Chong-Wah Ngo, Ting-Chuen Pong, Hong-Jiang Zhang Oct 2001

On Clustering And Retrieval Of Video Shots, Chong-Wah Ngo, Ting-Chuen Pong, Hong-Jiang Zhang

Research Collection School Of Computing and Information Systems

Clustering of video data is an important issue in video abstraction, browsing and retrieval. In this paper, we propose a two-level hierarchical clustering approach by aggregating shots with similar motion and color features. Motion features are computed directly from 20 tensor histograms, while color features are represented by 30 color histograms. Cluster validity analysis is further applied to automatically determine the number of clusters at each level. Video retrieval can then be done directly based on the result of clustering. The proposed approach is found to be useful particularly for sports games, where motion and color are important visual cues …


Modeling And Simulation Of Steady State And Transient Behaviors For Emergent Socs, Joann M. Paul, Arne Suppe, Donald E. Thomas Oct 2001

Modeling And Simulation Of Steady State And Transient Behaviors For Emergent Socs, Joann M. Paul, Arne Suppe, Donald E. Thomas

Research Collection School Of Computing and Information Systems

We introduce a formal basis for viewing computer systems as mixed steady state and non-steady state (transient) behaviors to motivate novel design strategies resulting from simultaneous consideration of function, scheduling and architecture. We relate three design styles: Hierarchical decomposition, static mapping and directed platform that have traditionally been separate. By considering them together, we reason that once a steady state system is mapped to an architecture, the unused processing and communication power may be viewed as a platform for a transient system, ultimately resulting in more effective design approaches that ease the static mapping problem while still allowing for effective …


Integrating Color And Spatial Features For Content-Based Video Retrieval, Tong Lin, Chong-Wah Ngo, Hong-Jiang Zhang, Qing-Yun Shi Oct 2001

Integrating Color And Spatial Features For Content-Based Video Retrieval, Tong Lin, Chong-Wah Ngo, Hong-Jiang Zhang, Qing-Yun Shi

Research Collection School Of Computing and Information Systems

In this paper, we present a novel and efficient scheme for extracting, indexing and retrieving color images. Our motivation was to reduce the space overhead of partition-based approaches taking advantage of the fact that only a relatively low number of distinct values of a particular visual feature is present in most images. To extract color feature and build indices into our image database we take into consideration factors such as human color perception and perceptual range, and the image is partitioned into a set of regions by using a simple classifying scheme. The compact color feature vector and the spatial …


Mining Multi-Level Rules With Recurrent Items Using Fp'-Tree, Kok-Leong Ong, Wee-Keong Ng, Ee Peng Lim Oct 2001

Mining Multi-Level Rules With Recurrent Items Using Fp'-Tree, Kok-Leong Ong, Wee-Keong Ng, Ee Peng Lim

Research Collection School Of Computing and Information Systems

Association rule mining has received broad research in the academic and wide application in the real world. As a result, many variations exist and one such variant is the mining of multi-level rules. The mining of multi-level rules has proved to be useful in discovering important knowledge that conventional algorithms such as Apriori, SETM, DIC etc., miss. However, existing techniques for mining multi-level rules have failed to take into account the recurrence relationship that can occur in a transaction during the translation of an atomic item to a higher level representation. As a result, rules containing recurrent items go unnoticed. …


Jointly Coordinating Ecn And Tcp For Rapid Adaptation To Varying Bandwidth, Archan Misra, Teunis Ott Oct 2001

Jointly Coordinating Ecn And Tcp For Rapid Adaptation To Varying Bandwidth, Archan Misra, Teunis Ott

Research Collection School Of Computing and Information Systems

The introduction of service differentiation in the Internet implies that the residual bandwidth available to best-effort traffic becomes highly variable. We explore the design of a rapidly-reactive congestion control framework, where the ECN-aware best-effort flows aggressively go after any unused capacity. By making routers mark packets in a much more aggressive manner, we are able to achieve fast backoff in the network without resorting to the TCP's current drastic step of halving the congestion window. Simulations indicate that our ECN-mod protocol is better than ECN-NewReno in exploiting rapid variations in the available bandwidth. Moreover, the milder backoff policy of ECN-mod …


Hierarchical Mobility Management For Voip Traffic, Archan Misra, Subir Das, Anthony J. Mcauley Oct 2001

Hierarchical Mobility Management For Voip Traffic, Archan Misra, Subir Das, Anthony J. Mcauley

Research Collection School Of Computing and Information Systems

A hierarchical IP-based mobility management mechanism is proposed for VoIP applications. The suggested mechanism uses the DMA (dynamic mobility agent) architecture, based on IDMP (intra-domain mobility management protocol), for managing intra-domain mobility and the dynamic binding mechanism of SIP (session initiation protocol) for managing global mobility. This combination of network and application layer mobility management reduces the global signaling load, provides fast handoff for ongoing conversations, enables efficient global transport and supports IP-layer paging.


Exploiting Image Indexing Techniques In Dct Domain, Chong-Wah Ngo, Ting-Chuen Pong, Ronald T. Chin Sep 2001

Exploiting Image Indexing Techniques In Dct Domain, Chong-Wah Ngo, Ting-Chuen Pong, Ronald T. Chin

Research Collection School Of Computing and Information Systems

This paper is concerned with the indexing and retrieval of images based on features extracted directly from the JPEG discrete cosine transform (DCT) domain. We examine possible ways of manipulating DCT coefficients by standard image analysis approaches to describe image shape, texture, and color. Through the Mandala transformation, our approach groups a subset of DCT coefficients to form ten blocks. Each block represents a particular frequency content of the original image. Two blocks are used to model rough object shape; nine blocks to describe subband properties; and one block to compute color distribution. As a result, the amount of data …


Vide: A Visual Data Extraction Environment For The Web, Yi Li, Wee-Keong Ng, Ee Peng Lim Sep 2001

Vide: A Visual Data Extraction Environment For The Web, Yi Li, Wee-Keong Ng, Ee Peng Lim

Research Collection School Of Computing and Information Systems

With the rapid growth of information on the Web, a means to combat information overload is critical. In this paper, we present ViDE (Visual Data Extraction), an interactive web data extraction environment that supports efficient hierarchical data wrapping of multiple web pages. ViDE has two unique features that differentiate it from other extraction mechanisms. First, data extraction rules can be easily specified in a graphical user interface that is seamlessly integrated with a web browser. Second, ViDE introduces the concept of grouping which unites the extraction rules for a set of documents with the navigational patterns that exist among them. …


Nonparametric Techniques To Extract Fuzzy Rules For Breast Cancer Diagnosis Problem, Manish Sarkar, Tze-Yun Leong Sep 2001

Nonparametric Techniques To Extract Fuzzy Rules For Breast Cancer Diagnosis Problem, Manish Sarkar, Tze-Yun Leong

Research Collection School Of Computing and Information Systems

This paper addresses breast cancer diagnosis problem as a pattern classification problem. Specifically, the problem is studied using Wisconsin-Madison breast cancer data set. Fuzzy rules are generated from the input-output relationship so that the diagnosis becomes easier and transparent for both patients and physicians. For each class, at least one training pattern is chosen as the prototype, provided (a) the maximum membership of the training pattern is in the given class, and (b) among all the training patterns, the neighborhood of this training pattern has the least fuzzy-rough uncertainty in the given class. Using the fuzzy-rough uncertainty, a cluster is …


Autoconfiguration, Registration And Mobility Management For Pervasive Computing, Archan Misra, Subir Das, Anthony Mcauley, Sajal K. Das Aug 2001

Autoconfiguration, Registration And Mobility Management For Pervasive Computing, Archan Misra, Subir Das, Anthony Mcauley, Sajal K. Das

Research Collection School Of Computing and Information Systems

In the vision of pervasive computing, users will exchange information and control their environments from anywhere using various wireline/wireless networks and computing devices. We believe that current protocols, such as DHCP, PPP, and Mobile IP, must be enhanced to support pervasive network access. In particular, this article identifies three fundamental functions: autoconfiguration, registration, and mobility management, that need such enhancements. Realizing that the IP autoconfiguration capabilities must be extended to configure routers and large dynamic networks, we first describe our autoconfiguration solution based on the dynamic configuration and distribution protocol (DCDP). Second, we discuss why providing user-specific services over a …


Role Of Use Case Diagram In Requirement Analysis, Keng Siau, L. Lee Aug 2001

Role Of Use Case Diagram In Requirement Analysis, Keng Siau, L. Lee

Research Collection School Of Computing and Information Systems

Since its debut and acceptance as a de facto standard of the object-oriented paradigm, UML has receivedcontroversial reviews. The most controversial diagramming technique in UML is undoubtedly the Use Casediagrams. Some claim that Use Case diagrams do not play a valuable role in requirement analysis. Othersargue that Use Case diagrams captured neither the static nor the dynamic aspects of the systems. The objective of this study is to investigate the role and value of Use Case diagrams in requirement analysis. We will investigate the information content of Use Case diagram and its role in requirement analysis.


Research Issues In Human-Computer Interaction In The Web-Based Environment, Fiona Fui-Hoon Nah, Sid Davis Aug 2001

Research Issues In Human-Computer Interaction In The Web-Based Environment, Fiona Fui-Hoon Nah, Sid Davis

Research Collection School Of Computing and Information Systems

The Internet and WWW are revolutionizing our daily lives and the way business is conducted. Since 1997, the Web has gradually evolved into a true economy and a new frontier for business. In this new Internet age, the design of a quality Web site is critical to the success of businesses. To attract and retain visitors, Web sites need to be human-centered, easy and quick to navigate, and speak the visitor’s language. User experience with the Web site is also important. The experience should be in line with the user’s goal and should feel natural to the user. Unfortunately, principles …


Video Partitioning By Temporal Slice Coherency, Chong-Wah Ngo, Ting-Chuen Pong, Roland T. Chin Aug 2001

Video Partitioning By Temporal Slice Coherency, Chong-Wah Ngo, Ting-Chuen Pong, Roland T. Chin

Research Collection School Of Computing and Information Systems

We present a novel approach for video partitioning by detecting three essential types of camera breaks, namely cuts, wipes, and dissolves. The approach is based on the analysis of temporal slices which are extracted from the video by slicing through the sequence of video frames and collecting temporal signatures. Each of these slices contains both spatial and temporal information from which coherent regions are indicative of uninterrupted video partitions separated by camera breaks. Properties could further be extracted from the slice for both the detection and classification of camera breaks. For example, cut and wipes are detected by color-texture properties, …


An Integrated Model On Computer Abuse: A Pilot Study, S. G. Lee, Fiona Fui-Hoon Nah, S. Yoo Aug 2001

An Integrated Model On Computer Abuse: A Pilot Study, S. G. Lee, Fiona Fui-Hoon Nah, S. Yoo

Research Collection School Of Computing and Information Systems

In spite of continuous organizational efforts and investments based on systematic factors, the incidence of computer abuse in organizations is still rapidly increasing. This paper proposes another perspective -- based on the general strain theory -- in preventing computer abuse. According to the general strain theory, organizational trust, which comprises organizational attachment, commitment, involvement, and norms, can prevent computer abuse by reducing insidersí computer abuse. The aim of this article is to assess the role of organizational trust from the perspectives of attachment, commitment, involvement, and norms in preventing computer abuse. The results indicate that both organizational trust and deterrent …


A Multi-Agent Framework For Supporting Intelligent Fourth-Party Logistics, Hoong Chuin Lau, G. Lo Aug 2001

A Multi-Agent Framework For Supporting Intelligent Fourth-Party Logistics, Hoong Chuin Lau, G. Lo

Research Collection School Of Computing and Information Systems

A distributed intelligent agent-based framework that supports fourth-party logistics optimization under a web-based e-Commerce environment has been proposed in this paper. In the framework, customer job requests come through an e-Procurement service. These requests are consolidated and pushed to the e-Market Place service periodically. The e-Market Place then serves as a broker that allows intelligent agents to bid to serve these requests optimally in real-time by solving multiple instances of underlying logistics optimization problem. The resulting system was implemented based on the Java 2 Enterprise Edition (J2EE) platform using distributed system technology for communication between objects.


Analysis Of A New Vehicle Scheduling And Location Problem, Ebru K. Bish, Thin Yin Leong, Chun-Lun Li, Jonathan W. C. Ng, David Simchi-Levi Aug 2001

Analysis Of A New Vehicle Scheduling And Location Problem, Ebru K. Bish, Thin Yin Leong, Chun-Lun Li, Jonathan W. C. Ng, David Simchi-Levi

Research Collection School Of Computing and Information Systems

We consider a container terminal discharging containers from a ship and locating them in the terminal yard. Each container has a number of potential locations in the yard where it can be stored. Containers are moved from the ship to the yard using a fleet of vehicles, each of which can carry one container at a time. The problem is to assign each container to a yard location and dispatch vehicles to the containers so as to minimize the time it takes to download all the containers from the ship. We show that the problem is NP-hard and develop a …


A Method For Fast Revocation Of Public Key Certificates And Security Capabilities, D. Boneh, Xuhua Ding, Gene Tsudik, Chi Ming Wong Aug 2001

A Method For Fast Revocation Of Public Key Certificates And Security Capabilities, D. Boneh, Xuhua Ding, Gene Tsudik, Chi Ming Wong

Research Collection School Of Computing and Information Systems

We present a new approach to fast certificate revocation centered around the concept of an on-line semi-trusted mediator (SEM). The use of a SEM in conjunction with a simple threshold variant of the RSA cryptosystem (mediated RSA) offers a number of practical advantages over current revocation techniques. Our approach simplifies validation of digital signatures and enables certificate revocation within legacy systems. It also provides immediate revocation of all security capabilities. This paper discusses both the architecture and implementation of our approach as well as performance and compatibility with the existing infrastructure. Our results show that threshold cryptography is practical for …