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Articles 6991 - 7020 of 7446

Full-Text Articles in Physical Sciences and Mathematics

A Smart-Card-Enabled Privacy Preserving E-Prescription System, Yanjiang Yang, Xiaoxi Han, Feng Bao, Robert H. Deng Mar 2004

A Smart-Card-Enabled Privacy Preserving E-Prescription System, Yanjiang Yang, Xiaoxi Han, Feng Bao, Robert H. Deng

Research Collection School Of Computing and Information Systems

Within the overall context of protection of health care information, privacy of prescription data needs special treatment. First, the involvement of diverse parties, especially nonmedical parties in the process of drug prescription complicates the protection of prescription data. Second, both patients and doctors have privacy stakes in prescription, and their privacy should be equally protected. Third, the following facts determine that prescription should not be processed in a truly anonymous manner: certain involved parties conduct useful research on the basis of aggregation of prescription data that are linkable with respect to either the patients or the doctors; prescription data has …

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A Modeling Framework For Computing Lifetime And Information Capacity In Wireless Sensor Networks, Enrique Duarte-Melo, Mingyan Liu, Archan Misra Mar 2004

A Modeling Framework For Computing Lifetime And Information Capacity In Wireless Sensor Networks, Enrique Duarte-Melo, Mingyan Liu, Archan Misra

Research Collection School Of Computing and Information Systems

In this paper we investigate the expected lifetime and information capacity, defined as the maximum amount of data (bits) transferred before the first sensor node death due to energy depletion, of a data-gathering wireless sensor network. We develop a fluidflow based computational framework that extends the existing approach, which requires precise knowledge of the layout/deployment of the network, i.e., exact sensor positions. Our method, on the other hand, views a specific network deployment as a particular instance (sample path) from an underlying distribution of sensor node layouts and sensor data rates.

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An Information-Theoretic Framework For Optimal Location Tracking In Multi-System 4g Wireless Networks, Archan Misra, Abhishek Roy, Sajal K. Das Mar 2004

An Information-Theoretic Framework For Optimal Location Tracking In Multi-System 4g Wireless Networks, Archan Misra, Abhishek Roy, Sajal K. Das

Research Collection School Of Computing and Information Systems

An information-theoretic framework is developed for optimal location management in multisystem, fourth generation (4G) wireless networks. The framework envisions that each individual subsystem operates fairly independently, and does not require public knowledge of individual subnetwork topologies. To capture the variation in paging and location update costs in this heterogeneous environment, the location management problem is formulated in terms of a new concept of weighted entropy. The update process is based on the Lempel-Ziv compression algorithms, which are applied to a vector-valued sequence consisting of both the mobile's movement pattern and its session activity state. Three different tracking strategies which differ …

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Spatial Queries In The Presence Of Obstacles, Jun Zhang, Dimitris Papadias, Kyriakos Mouratidis, Manli Zhu Mar 2004

Spatial Queries In The Presence Of Obstacles, Jun Zhang, Dimitris Papadias, Kyriakos Mouratidis, Manli Zhu

Research Collection School Of Computing and Information Systems

Despite the existence of obstacles in many database applications, traditional spatial query processing utilizes the Euclidean distance metric assuming that points in space are directly reachable. In this paper, we study spatial queries in the presence of obstacles, where the obstructed distance between two points is defined as the length of the shortest path that connects them without crossing any obstacles. We propose efficient algorithms for the most important query types, namely, range search, nearest neighbors, e-distance joins and closest pairs, considering that both data objects and obstacles are indexed by R-trees. The effectiveness of the proposed solutions is verified …

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An Automated Algorithm For Extracting Website Skeleton, Zehua Liu, Wee-Keong Ng, Ee Peng Lim Mar 2004

An Automated Algorithm For Extracting Website Skeleton, Zehua Liu, Wee-Keong Ng, Ee Peng Lim

Research Collection School Of Computing and Information Systems

The huge amount of information available on the Web has attracted many research efforts into developing wrappers that extract data from webpages. However, as most of the systems for generating wrappers focus on extracting data at page-level, data extraction at site-level remains a manual or semi-automatic process. In this paper, we study the problem of extracting website skeleton, i.e. extracting the underlying hyperlink structure that is used to organize the content pages in a given website. We propose an automated algorithm, called the Sew algorithm, to discover the skeleton of a website. Given a page, the algorithm examines hyperlinks in …

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Tool Support For Two-Tiered Architectural Design For Automotive Control Systems, Kevin Steppe, Greg Bylenok, David Garlan, Bradley Schmerl, Kanat Abirov, Nataliya Shevchenko Jan 2004

Tool Support For Two-Tiered Architectural Design For Automotive Control Systems, Kevin Steppe, Greg Bylenok, David Garlan, Bradley Schmerl, Kanat Abirov, Nataliya Shevchenko

Research Collection School Of Computing and Information Systems

An attractive approach to architecture-based design is to structure the development process into two tiers. The top tier represents the abstract design (or architecture) of a system in terms of abstract components. The bottom tier refines that design by making specific implementation decisions, such as platform, middleware, and component implementations. While attractive in principle, there has been relatively little industrial-based experience to shed light on problems and solutions involved in such an approach. In this paper we describe our experience in developing tools to introduce a two-tiered model-based approach to the design of Ford Motor Company’s automotive control systems, highlighting …

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Parameter Selection In Genetic Algorithms, Onur Boyabatli, Ihsan Sabuncuoglu Jan 2004

Parameter Selection In Genetic Algorithms, Onur Boyabatli, Ihsan Sabuncuoglu

Research Collection Lee Kong Chian School Of Business

In this study, we provide a new taxonomy of parameters of genetic algorithms (GA), structural and numerical parameters, and analyze the effect of numerical parameters on the performance of GA based simulation optimization applications with experimental design techniques. Appropriate levels of each parameter are proposed for a particular problem domain. Controversial to existing literature on GA, our computational results reveal that in the case of a dominant set of decision variable the crossover operator does not have a significant impact on the performance measures, whereas high mutation rates are more suitable for GA applications.

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Qos Routing Optimization Strategy Using Genetic Algorithm In Optical Fiber Communication Networks, Zhaoxia Wang, Zengqiang Chen, Zhuzhi Yuan Jan 2004

Qos Routing Optimization Strategy Using Genetic Algorithm In Optical Fiber Communication Networks, Zhaoxia Wang, Zengqiang Chen, Zhuzhi Yuan

Research Collection School Of Computing and Information Systems

This paper describes the routing problems in optical fiber networks, defines five constraints, induces and simplifies the evaluation function and fitness function, and proposes a routing approach based on the genetic algorithm, which includes an operator [OMO] to solve the QoS routing problem in optical fiber communication networks. The simulation results show that the proposed routing method by using this optimal maintain operator genetic algorithm (OMOGA) is superior to the common genetic algorithms (CGA). It not only is robust and efficient but also converges quickly and can be carried out simply, that makes it better than other complicated GA.

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Deviance Information Criterion For Comparing Stochastic Volatility Models, Andreas Berg, Renate Meyer, Jun Yu Jan 2004

Deviance Information Criterion For Comparing Stochastic Volatility Models, Andreas Berg, Renate Meyer, Jun Yu

Research Collection School Of Economics

Bayesian methods have been efficient in estimating parameters of stochastic volatility models for analyzing financial time series. Recent advances made it possible to fit stochastic volatility models of increasing complexity, including covariates, leverage effects, jump components, and heavy-tailed distributions. However, a formal model comparison via Bayes factors remains difficult. The main objective of this article is to demonstrate that model selection is more easily performed using the deviance information criterion (DIC). It combines a Bayesian measure of fit with a measure of model complexity. We illustrate the performance of DIC in discriminating between various different stochastic volatility models using simulated …

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Java-Based Digital Library Portal For Geography Education, Zehua Liu, Hai Yuan, Ee Peng Lim, Ming Yin, Dion Hoe-Lian Goh, Yin-Leng Theng, Wee-Keong Ng Jan 2004

Java-Based Digital Library Portal For Geography Education, Zehua Liu, Hai Yuan, Ee Peng Lim, Ming Yin, Dion Hoe-Lian Goh, Yin-Leng Theng, Wee-Keong Ng

Research Collection School Of Computing and Information Systems

G-Portal is a Java-based digital library system for managing the metadata of geography related resources on the Web. In addition to providing a flexible repository subsystem to accommodate metadata of different formats using XML and XML Schemas, G-Portal organizes metadata into projects and layers, and supports an integrated and synchronized classification and map-based interfaces over the stored metadata. G-Portal also includes a classification subsystem that creates category structures and classifies metadata resources into categories based on user-specified classification schemas. Furthermore, G-Portal users can annotate resources and make their annotations available to others. In this paper, we describe the design and …

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Web Usage Mining: Algorithms And Results, Ee Peng Lim, Yew-Kwong Woon, Wee-Keong Ng Jan 2004

Web Usage Mining: Algorithms And Results, Ee Peng Lim, Yew-Kwong Woon, Wee-Keong Ng

Research Collection School Of Computing and Information Systems

No abstract provided.

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Viscors: A Visual-Content Recommender For The Mobile Web, Chan Young Kim, Jae Kyu Lee, Yoon Ho Cho, Deok Hwan Kim Jan 2004

Viscors: A Visual-Content Recommender For The Mobile Web, Chan Young Kim, Jae Kyu Lee, Yoon Ho Cho, Deok Hwan Kim

Research Collection School Of Computing and Information Systems

Current search methods for mobile-Web content can be frustrating to use. To shorten searches for cell phone wallpaper images, VISCORS combines collaborative filtering with content-based image retrieval. An increasing selection of content is becoming available in the mobile-Web environment, where users navigate the Web using wireless devices such as cell phones and PDAs. The fast growth and excellent prospects of the mobile-Web content market have attracted many content providers.

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Logistics Outsourcing And 3pl Challenges, Michelle L. F. Cheong Jan 2004

Logistics Outsourcing And 3pl Challenges, Michelle L. F. Cheong

Research Collection School Of Computing and Information Systems

Logistics has been an important part of every economy and every business entity. The worldwide trend in globalization has led to many companies outsourcing their logistics function to Third-Party Logistics (3PL) companies, so as to focus on their core competencies. This paper attempts to broadly identify and categorize the challenges faced by 3PL companies and discover potential gaps for future research. Some of the challenges will be related with the experience and information collected from interviews with two 3PL companies.

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Powerful Change Part 2: Reducing The Power Demands Of Mobile Devices, Rajesh Krishna Balan Jan 2004

Powerful Change Part 2: Reducing The Power Demands Of Mobile Devices, Rajesh Krishna Balan

Research Collection School Of Computing and Information Systems

Consumers expect their mobile devices to be small and light, have a decent battery lifetime, and still be powerful enough to run all their desired applications. The need to satisfy such consumer demands has driven mobile-device manufacturers to make products (such as PDAs and cell phones) that match these needs. However, this inevitably requires tradeoffs. Building smaller, lighter devices requires sacrificing the device's battery capacity because battery technology is still fairly dense and heavy, and contributes most of a mobile device's size and weight. But, mobile devices with the required resources to run useful desktop applications need additional battery power …

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A Secure And Privacy Enhanced Location-Based Service Transaction Protocol In Ubiquitous Computing Environment, Konidala Divyan, Robert H. Deng, Jianying Zhou, Kwanjo Kim Jan 2004

A Secure And Privacy Enhanced Location-Based Service Transaction Protocol In Ubiquitous Computing Environment, Konidala Divyan, Robert H. Deng, Jianying Zhou, Kwanjo Kim

Research Collection School Of Computing and Information Systems

Nowadays mobile phones and PDAs are part and parcel of our lives. By carrying a portable mobile device with us all the time we are already living in partial Pervasive Computing Environment (PCE) that is waiting to be exploited very soon. One of the advantages of pervasive computing is that it strongly supports the deployment of Location-Based Service(s) (LBSs). In PCE, there would be many competitive service providers (SPs) trying to sell different or similar LBSs to users. In order to avail a particular service, it becomes very di#cult for a low-computing and resourcepoor mobile device to handle many such …

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Design And Analysis Of Cylindrical Antiresonant Reflecting Optical Waveguide, Chyng Wen Tee, S. F. Yu Dec 2003

Design And Analysis Of Cylindrical Antiresonant Reflecting Optical Waveguide, Chyng Wen Tee, S. F. Yu

Research Collection Lee Kong Chian School Of Business

A field-transfer matrix method is developed to analyze the modal characteristics of cylindrical multilayered waveguides with axis-symmetric geometry. A new design rule for cylindrical antiresonant reflecting optical waveguides (ARROWs), based on a three-step design process, is also proposed to minimize the radiation loss of the fundamental leaky mode. In addition, a simple approach is suggested to estimate the optimum core diameter of the cylindrical ARROWs for optimum radiation loss and radiation loss margin. Hence, it can be shown that an extra high index cladding layer is good enough to reduce the radiation loss as well as to maintain a reasonably …

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Predicting Nonlinear Network Traffic Using Fuzzy Neural Network, Zhaoxia Wang, Tingzhu Hao, Zengqiang Chen, Zhuzhi Yuan Dec 2003

Predicting Nonlinear Network Traffic Using Fuzzy Neural Network, Zhaoxia Wang, Tingzhu Hao, Zengqiang Chen, Zhuzhi Yuan

Research Collection School Of Computing and Information Systems

Network traffic is a complex and nonlinear process, which is significantly affected by immeasurable parameters and variables. This paper addresses the use of the five-layer fuzzy neural network (FNN) for predicting the nonlinear network traffic. The structure of this system is introduced in detail. Through training the FNN using back-propagation algorithm with inertia] terms the traffic series can be well predicted by this FNN system. We analyze the performance of the FNN in terms of prediction ability as compared with solely neural network. The simulation demonstrates that the proposed FNN is superior to the solely neural network systems. In addition, …

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Xstamps: A Multiversion Timestamps Concurrency Control Protocol For Xml Data, Khin-Myo Win, Wee-Keong Ng, Ee Peng Lim Dec 2003

Xstamps: A Multiversion Timestamps Concurrency Control Protocol For Xml Data, Khin-Myo Win, Wee-Keong Ng, Ee Peng Lim

Research Collection School Of Computing and Information Systems

With the tremendous growth of XML data over the Web, efficient management of such data becomes a new challenge for database community. Several data management solutions, proposed in recent years, extend the capability of traditional database systems to meet the needs of XML data while alternative approaches introduce new generation databases, named as native XML database management systems. Although traditional databases have mature transaction management and concurrency control techniques, there is still a need to tailor techniques for native XML databases in order to deal with distinct characteristics of XML. In this paper, we propose XStamps, a multiversion timestamps concurrency …

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Paper For An Educational Digital Library, Dion Hoe-Lian Goh, Yin-Leng Theng, Ming Yin, Ee Peng Lim Dec 2003

Paper For An Educational Digital Library, Dion Hoe-Lian Goh, Yin-Leng Theng, Ming Yin, Ee Peng Lim

Research Collection School Of Computing and Information Systems

GeogDL is a digital library of geography examination resources designed to assist students in revising for a national geography examination in Singapore. As part of an iterative design process, we carried out participatory design and brainstorming with student and teacher design partners. The first study involved prospective student design partners. In response to the first study, we describe in this paper an implementation of PAPER – Personalised Adaptive Pathways for Exam Resources – a new bundle of personalized, interactive services containing a mock exam and a personal coach. The mock exam provides a simulation of the actual geography examination while …

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Structuring Lecture Videos For Distance Learning Applications, Chong-Wah Ngo, Feng Wang, Ting-Chuen Pong Dec 2003

Structuring Lecture Videos For Distance Learning Applications, Chong-Wah Ngo, Feng Wang, Ting-Chuen Pong

Research Collection School Of Computing and Information Systems

This paper presents an automatic and novel approach in structuring and indexing lecture videos for distance learning applications. By structuring video content, we can support both topic indexing and semantic querying of multimedia documents. In this paper, our aim is to link the discussion topics extracted from the electronic slides with their associated video and audio segments. Two major techniques in our proposed approach include video text analysis and speech recognition. Initially, a video is partitioned into shots based on slide transitions. For each shot, the embedded video texts are detected, reconstructed and segmented as high-resolution foreground texts for commercial …

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Apparatus For Discovering Computing Services Architecture And Developing Patterns Of Computing Services And Method Therefor [Sg 107499], Emarson Victoria, Hui Tseng, Hwee Hwa Pang, Tau Chen Cham, Siew Choo Tay Nov 2003

Apparatus For Discovering Computing Services Architecture And Developing Patterns Of Computing Services And Method Therefor [Sg 107499], Emarson Victoria, Hui Tseng, Hwee Hwa Pang, Tau Chen Cham, Siew Choo Tay

Research Collection School Of Computing and Information Systems

An apparatus for discovering computing services architecture and developing patterns of computing services and method therefor are disclosed. The apparatus, according to an embodiment of the invention, provides a graphical user interface for displaying a deployment plan of deployed computing services. Components in the deployment plan are interconnected by links indicating dependency relationships between the components. Each component and link is assigned a confidence value, which is based on a calculated weight of the properties of each component. The apparatus further provides editing tools for manipulating the components in the deployment plan as well as for creating and managing patterns.

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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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Aa Flexible And Scalable Authentication Scheme For Jpeg 2000 Image Codestreams, Cheng Peng, Robert H. Deng, Yongdong Wu, Weizhong Shao Nov 2003

Aa Flexible And Scalable Authentication Scheme For Jpeg 2000 Image Codestreams, Cheng Peng, Robert H. Deng, Yongdong Wu, Weizhong Shao

Research Collection School Of Computing and Information Systems

JPEG2000 is an emerging standard for still image compression and is becoming the solution of choice for many digital imaging fields and applications. An important aspect of JPEG2000 is its "compress once, decompress many ways" property [1], i. e., it allows extraction of various sub-images (e.g., images with various resolutions, pixel fidelities, tiles and components) all from a single compressed image codestream. In this paper, we present a flexible and scalable authentication scheme for JPEG2000 images based on the Merkle hash tree and digital signature. Our scheme is fully compatible with JPEG2000 and possesses a "sign once, verify many ways" …

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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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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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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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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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A Note On The Numerical Solution Of High-Order Differential Equations, Y. Wang, Yibao Zhao, G. W. Wei Oct 2003

A Note On The Numerical Solution Of High-Order Differential Equations, Y. Wang, Yibao Zhao, G. W. Wei

Research Collection Lee Kong Chian School Of Business

Numerical solution of high-order differential equations with multi-boundary conditions is discussed in this paper. Motivated by the discrete singular convolution algorithm, the use of fictitious points as additional unknowns is proposed in the implementation of locally supported Lagrange polynomials. The proposed method can be regarded as a local adaptive differential quadrature method. Two examples, an eigenvalue problem and a boundary-value problem, which are governed by a sixth-order differential equation and an eighth-order differential equation, respectively, are employed to illustrate the proposed method.

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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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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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