ppxscal/embedding_network huggingface dataset:
A second order discontinuous Galerkin fast sweeping method for Eikonal equations
Authors: Fengyan Li, Chi-Wang Shu, Yong-Tao Zhang, Hongkai Zhao
Venue: Journal of Computational Physics (2008)

In this paper, we construct a second order fast sweeping method with a discontinuous Galerkin (DG) local solver for computing viscosity solutions of a class of static Hamilton-Jacobi equations, namely the Eikonal equations. Our piecewise linear DG local solver is built on a DG method developed recently [Y. Cheng, C.-W. Shu, A discontinuous Galerkin finite element method for directly solving the Hamilton-Jacobi equations, Journal of Computational Physics 223 (2007) 398-415] for the time-dependent Hamilton-Jacobi equations. The causality property of Eikonal equations is incorporated into the design of this solver. The resulting local nonlinear system in the Gauss-Seidel iterations is a simple quadratic system and can be solved explicitly. The compactness of the DG method and the fast sweeping strategy lead to fast convergence of the new scheme for Eikonal equations. Extensive numerical examples verify efficiency, convergence and second order accuracy of the proposed method.
Bounded Adjacent Fill for Low Capture Power Scan Testing
Authors: Anshuman Chandra, Rohit Kapur
Venue: Proceedings of the 26th IEEE VLSI Test Symposium (2008)

Average and peak power dissipation can be reduced by controlling the switching activity in the scan chains during shift and capture cycles. In particular, minimum transition count or adjacent fill algorithm reduces transitions in the scan chains and has been shown to reduce average power dissipation during shift. In this paper, we show via statistical analysis of industrial circuits that contrary to conventional belief, scan-in and scan-out vectors are highly correlated for adjacent fill vectors. We also show that this correlation can be used to control the switching activity during the capture cycle. We propose a new filling algorithm called Bounded Adjacent fill that generates test vectors with low shift and capture switching activity and with no impact on pattern count.
ADAPTIVE AND INTELLIGENT REQUEST DISTRIBUTION FOR CONTENT DELIVERY NETWORKS
Authors: Leszek Borzemski, Krzysztof Zatwarnicki, Anna Zatwarnicka
Venue: Cybernetics and Systems (2007)

Today's knowledge and content Web-based technologies call for adaptive and intelligent algorithms for accessing the resources, especially to respond to Semantic Web, as well to performance challenges. This work presents the application of two machine learning techniques in an adaptive decision making framework, namely a fuzzy logic and neural networks, to deploy the adaptive and intelligent dispatching algorithm for resource requesting within a geographically distributed fully replicated Web sites. Our approach and algorithm can be used in content distribution and delivery networks where due to content replication each Web server can respond to the client request. Intelligent redirection mechanism redirects the request from the originating site's server to the "best" content source to deliver the content in the fastest manner. First, we introduce a broker-based system architecture. Next, we develop a new global adaptive intelligent request distribution algorithm. Our algorithm called GARDiB by a means of the fuzzy-neural techniques redirects each incoming request to local service with the least expected response time, which takes into account, the transfer time of the request and the response, as well as the time elapsed on the local service that responds to the request. Our simulations showed the effectiveness of the proposed adaptive distribution.
Translation of on-screen text into visual expressions
Authors: Kumiko Fujisawa, Kenro Aihara
Venue: Proceedings of the 8th ACM/IEEE-CS joint conference on Digital libraries (2008)

To support the user's on-screen reading, we propose a methodology to translate text into visual expressions. Our prototype system analyses the text and translates them into image and adds movement to the image.
Finding bugs in java native interface programs
Authors: Goh Kondoh, Tamiya Onodera
Venue: Proceedings of the 2008 international symposium on Software testing and analysis (2008)

In this paper, we describe static analysis techniques for finding bugs in programs using the Java Native Interface (JNI). The JNI is both tedious and error-prone because there are many JNI-specific mistakes that are not caught by a native compiler. This paper is focused on four kinds of common mistakes. First, explicit statements to handle a possible exception need to be inserted after a statement calling a Java method. However, such statements tend to be forgotten. We present a typestate analysis to detect this exception-handling mistake. Second, while the native code can allocate resources in a Java VM, those resources must be manually released, unlike Java. Mistakes in resource management cause leaks and other errors. To detect Java resource errors, we used the typestate analysis also used for detecting general memory errors. Third, if a reference to a Java resource lives across multiple native method invocations, it should be converted into a global reference. However, programmers sometimes forget this rule and, for example, store a local reference in a global variable for later uses. We provide a syntax checker that detects this bad coding practice. Fourth, no JNI function should be called in a critical region. If called there, the current thread might block and cause a deadlock. Misinterpreting the end of the critical region, programmers occasionally break this rule. We present a simple typestate analysis to detect an improper JNI function call in a critical region. We have implemented our analysis techniques in a bug-finding tool called BEAM, and executed it on opensource software including JNI code. In the experiment, our analysis techniques found 86 JNI-specific bugs without any overhead and increased the total number of bug reports by 76%.
Specifying Software Architectures Using a Formal-Based Approach
Authors: David Hemer, Yulin Ding
Venue: Proceedings of the 19th Australian Conference on Software Engineering (2008)

Architecture description languages (ADLs) describe the abstracted structure of a system. In this paper we describe a new ADL based on extension of the existing CARE language used in formally specifying and implementing reusable software components. The mainelements of this ADL are components and connectors, with functional and nonfunctional behaviours and interfaces defined. The ADL includes a configuration part, describing the connection between components and connectors, defined using a CSP-like notation. The ADL is amenable to the use of theorem proving techniques for establishing correctness of the architecture. The recursive architecture is also specified as a part of the communication. The design for the CARE ADL is incorporated with the plan to leverage existing tools for matching and adapting CARE components, to develop support for the detection and correction of architecture mismatches (i.e. where components do not interoperate correctly).
DiffServ-Based User-Manageable Quality of Service Control System
Authors: Karol Molnar, Vit Vrba
Venue: Proceedings of the Seventh International Conference on Networking (2008)

An efficient operation of modern network services in packet networks is often conditional on complex quality-of-service (QoS) support. Because of its relative simplicity the mechanism of Differentiated Services (DiffServ) has recently come to be the most widely used QoS support technology in IP networks. One of the biggest disadvantages of this mechanism is the inability to cooperate with end-stations and end-user applications. This paper introduces a solution which allows end-stations to automatically retrieve DiffServ-related information from a network. As a result, end-users can control traffic policing in the DiffServ domain provided the predefined traffic conditions are not violated.
Pose estimation and tracking using multivariate regression
Authors: Arasanathan Thayananthan, Ramanan Navaratnam, Björn Stenger, Philip H. S. Torr, Roberto Cipolla
Venue: Pattern Recognition Letters (2008)

This paper presents an extension of the relevance vector machine (RVM) algorithm to multivariate regression. This allows the application to the task of estimating the pose of an articulated object from a single camera. RVMs are used to learn a one-to-many mapping from image features to state space, thereby being able to handle pose ambiguity.
Autonomic Provisioning of Hosted Applications with Level of Isolation Terms
Authors: Carsten Franke, Philip Robinson
Venue: Proceedings of the Fifth IEEE Workshop on Engineering of Autonomic and Autonomous Systems (2008)

Autonomic provisioning of hosted applications in Enterprise Data Centers must be investigated as more and more business applications are executed in such an environment. In this scenario, the multiplicity and variability of software components and data to be dynamically deployed, interconnected and adjusted leads to more complex system management. In parallel, all customer requirements and constraints must be fulfilled. These requirements and constraints are specified in corresponding Service Level Agreements (SLA). Security aspects are one important part of such agreements, as in a shared, open infrastructure, perceived risks with respect to loss of information confidentiality, integrity and availability increase. Legislation and compensation mechanisms make it imperative for the Data Center to acknowledge these perceived risks. Therefore, robust application isolation mechanisms must be considered. However, potential drawbacks due to the used security mechanisms that might influence the overall system performance must be considered. In order to initialize an autonomic provisioning process, a concept for configuring the Data Center based on different Levels of Isolation is presented. Customers and Data Center providers can agree on the isolation guarantees they expect given their individual preferences specification between the perceived risks and the resulting costs associated with the chosen Level of Isolation.
QoS Aware Dependable Distributed Stream Processing
Authors: Vana Kalogeraki, Dimitrios Gunopulos, Ravi Sandhu, Bhavani Thuraisingham
Venue: Proceedings of the 2008 11th IEEE Symposium on Object Oriented Real-Time Distributed Computing (2008)

In this paper we describe our approach for developing a QoS-aware, dependable execution environment for large-scale distributed stream processing applications. Distributed stream processing applications have strong timeliness and security demands. In particular, we address the following challenges:(1) propose a real-time dependable execution model by extending the component-based execution model with real-time and dependability properties, and (2) develop QoS-aware application composition and adaptation techniques that employ resource management strategies and security policies when discovering and selecting application components. Our approach enables us to develop a distributed stream processing environment that is predictable, secure, flexible, and adaptable.
Access point selection algorithms for maximizing throughputs in wireless LAN environment
Authors: Akihiro Fujiwara, Yasuhiro Sagara, Masahiko Nakamura
Venue: Proceedings of the 13th International Conference on Parallel and Distributed Systems - Volume 01 (2007)

In wireless LAN technology, access point selection at each station is a critical problem in order to obtain satisfactory throughputs. The current protocol for access point selection is based on the received signal strength, and a concentration of stations causes a degradation of the entire wireless network. In the present paper, we propose two access point selection algorithms for maximizing two types of throughputs. The first algorithmis proposed for maximizing the average throughput of stations, and the second algorithm is proposed for maximizing the minimum throughput of stations. The experimental results of the proposed algorithms indicate that the proposed algorithms achieve a number of performance improvements compared with previous algorithms.
Choice of the regularization parameter in ill-posed problems with rough estimate of the noise level of data
Authors: Uno Hämarik, Toomas Raus
Venue: Proceedings of the 7th WSEAS International Conference on Applied Mathematics (2005)

We consider linear ill-posed problems Au = f in Hilbert spaces. Regularized approximations ur to solutions u* of problem Au = f are obtained by a general regularization scheme, including the Tikhonov method, iterative and other methods. We assume that instead of f ∈ R(A) noisy data f are available with the approximately given noise level δ: it holds ||f - f||/δ → C for δ → 0, but C = const is unknown. We propose a new a-posteriori rule for the choice of the regularization parameter r = r(δ) guaranteeing ur(δ) → u* for δ → 0. Note that such convergence is not guaranteed for the parameter choice by the discrepancy principle ||Aur - f|| = bδ with b < C and for parameter choice rules which do not use the noise level (quasioptimality criterion, Wahba's generalized cross-validation rule, Hansen's L-curve rule). We give error estimates which in case ||f - f|| ≤ δ are quasioptimal and order-optimal.
Performance capabilities of long-range UWB-IR TDOA localization systems
Authors: Richard J. Barton, Divya Rao
Venue: EURASIP Journal on Advances in Signal Processing (2008)

The theoretical and practical performance limits of a 2D ultra-wideband impulse-radio localization system operating in the far field are studied under the assumption that estimates of location are based on time-difference-of-arrival (TDOA) measurements. Performance is evaluated in the presence of errors in both the TDOA measurements and the sensor locations. The performance of both optimal (maximum-likelihood) and suboptimal location estimation algorithms is studied and compared with the theoretical performance limit defined by the Cramér-Rao lower bound on the variance of unbiased TDOA location estimates. A novel weighted total-least-squares algorithm is introduced that compensates somewhat for errors in sensor positions and reduces the bias in location estimation compared with a widely used weighted least-squares approach. In addition, although target tracking per se is not considered in this paper, performance is evaluated both under the assumption that sequential location estimates are not aggregated as well as under the assumption that some sort of tracker is available to aggregate a sequence of estimates.
InterviewDonald Knuth: A life's work interrupted
Authors: Len Shustek
Venue: Communications of the ACM (2008)

In this second of a two-part interview by Edward Feigenbaum, we find Knuth, having completed three volumes of The Art of Computer Programming, drawn to creating a system to produce books digitally.
Demonstration of Active Guidance with SmartCane
Authors: Lawrence K. Au, Winston H. Wu, Maxim A. Batalin, Thanos Stathopoulos, William J. Kaiser
Venue: Proceedings of the 7th international conference on Information processing in sensor networks (2008)

The usage of conventional assistive cane devices is critical in reducing the risk of falls, which are particularly detrimental for the elderly and disabled. Many of the individuals that experience the greatest risk of falling rely on cane devices for support of ambulation. However, the results of many studies have shown that incorrect cane usage is prevalent among cane users. The original SmartCane assistive system [4] has been developed to provide a method for acquiring detailed motion data from cane usage. The cane itself, however, lacks any type of programmability as well as real-time data processing algorithms to provide feedback to the cane user. In this demonstration, we have incorporated an embedded computing platform into SmartCane [2] and developed a real-time sensor information processing algorithm that provides direct detection of cane usage characteristics. The new system provides local data processing capability by classifying whether an individual is executing a stride with proper cane motion and applied forces. It also provides direct feedback information to the individual, thereby guiding the subject towards proper cane usage and reducing the risk of falls.
Model Checking Multi-Task Software on Real-Time Operating Systems
Authors: Toshiaki Aoki
Venue: Proceedings of the 2008 11th IEEE Symposium on Object Oriented Real-Time Distributed Computing (2008)

In this paper, we propose a method to verify software executed on RTOS which conforms to micro ITRON with a model checking tool Spin. The RTOS provides facilities such as priorities and service calls to controlthe execution of tasks, however, Spin does not provide them. Thus, we implemented a middleware which allows us to use the facilities and simulate the execution of the tasks in Spin. The paper shows how it is implemented and its evaluation.
Tagging and Tracking System for Prisons and Correctional Facilities - A Design Roadmap
Authors: Catherine Louise Mulholland, Roy Sterritt, Patricia O'Hagan, Edward Hanna
Venue: Proceedings of the Fifth IEEE Workshop on Engineering of Autonomic and Autonomous Systems (2008)

Prisons and correctional facilities, particularly within Europe, have moved away from the traditional role of restrictive management and into one more akin to mentoring and re-education. This change of direction coupled with staffing shortages creates the need for security systems capable of self-management to relieve prison staff of the more fundamental tasks of managing movement and interaction and allow them to focus on the individual. This paper aims to provide a potential design roadmap to the tagging and tracking element of an existing self-managing security system for use in prisons and correctional facilities. Logical processes and autonomic computing elements have been suggested to support self-management while tracking technology solutions are discussed that best uphold optimum data security. The use of SVG is considered as an animation capable user interface solution.
Towards personalized distributed information retrieval
Authors: Mark J. Carman, Fabio Crestani
Venue: Proceedings of the 31st annual international ACM SIGIR conference on Research and development in information retrieval (2008)

Our aim is to investigate if and how the performance of Distributed Information Retrieval (DIR) systems can be improved through personalization. Toward this aim we are building a testbed of document collections and corresponding personalized relevance judgments. In this paper we discuss our intended approach for personalizing the three different phases of the DIR process. We also describe the test collection we are building and discuss our methodology for evaluating personalized DIR using relevance information taken from social bookmarking data.
Using sub-band wavelet packets strategy for feature extraction
Authors: Jiang Hai, Er Meng Joo
Venue: Proceedings of the 2nd WSEAS International Conference on Electronics, Control and Signal Processing (2003)

In this paper, a new filter structure using Wavelet Packets (WPs) decomposition strategy based on different frequency bands is presented. These filters have the advantage of having more decomposition times in the human-ear-sensitive frequency segment than those in the human-ear-insensitive frequency segments. Each frequency segment has frequency bands spacing similar to the Mel scale. The framework of Linear Discriminant Analysis (LDA) is used to derive an efficient and reduced-dimension speech parametric vector space for the speech recognition system. Experiments are performed on the speaker independent isolated-word speech recognition task. It is found that the Sub-Band WPs method achieves better recognition performance than the Mel Filter-Like WPs method and the most popular Mel Frequency Cepstral Coefficients (MFCC) feature extraction method in a noisy environment.
How science students can learn about unobservable phenomena using computer-based analogies
Authors: Lana Trey, Samia Khan
Venue: Computers Education (2008)

A novel instructional computer simulation that incorporates a dynamic analogy to represent Le Chatelier's Principle was designed to investigate the contribution of this feature to students' understanding. Two groups of 12th grade Chemistry students (n=15) interacted with the computer simulation during the study. Both groups did the same pre-instructional and simulation activities except one of the groups interacted with the analogical example in the simulation and the other group was asked to recall an analogy that was presented in the form of text and pictures. A statistical analysis of the tests administered at the end of the study suggested that analogies that are dynamic, interactive, and integrated in a computer simulation may have a stronger effect on learning outcomes than analogies which are presented in the form of text and static pictures. The implication of this study for science educators is that dynamic computer-based analogies can enhance student learning of unobservable phenomena in science.
On guaranteed smooth switching for buffered crossbar switches
Authors: Si-Min He, Shu-Tao Sun, Hong-Tao Guan, Qiang Zheng, You-Jian Zhao, Wen Gao
Venue: IEEE/ACM Transactions on Networking (TON) (2008)

Scalability considerations drive the evolution of switch design from output queueing to input queueing and further to combined input and crosspoint queueing (CICQ). However, CICQ switches with credit-based flow control face new challenges of scalability and predictability. In this paper, we propose a novel approach of rate-based smoothed switching, and design a CICQ switch called the smoothed buffered crossbar or sBUX. First, the concept of smoothness is developed from two complementary perspectives of covering and spacing, which, commonly known as fairness and jitter, are unified in the same model. Second, a smoothed multiplexer sMUX is designed that allocates bandwidth among competing flows sharing a link and guarantees almost ideal smoothness for each flow. Third, the buffered crossbar sBUX is designed that uses the scheduler sMUX at each input and output, and a two-cell buffer at each crosspoint. It is proved that sBUX guarantees 100% throughput for real-time services and almost ideal smoothness for each flow. Fourth, an on-line bandwidth regulator is designed that periodically estimates bandwidth demand and generates admissible allocations, which enables sBUX to support best-effort services. Simulation shows almost 100% throughput and multi-microsecond average delay. In particular, neither credit-based flow control nor speedup is used, and arbitrary fabric-internal latency is allowed between line cards and the switch core, simplifying the switch implementation.
Quality of Service guarantees and fault-tolerant TCP services in mobile wireless optical networks
Authors: Ionut Cardei, Allalaghatta Pavan, Riccardo Bettati
Venue: International Journal of Ad Hoc and Ubiquitous Computing (2008)

In this paper we address the problem for communications Quality of Service (QoS) in wireless networks of Mobile Optical Free-space networks. We propose an architecture for end-to-end statistical delay guarantees. A delay model using the concept of virtual traffic accommodates variations in link capacity variations as well as transient outages. The QoS architecture uses an admission control technique that limits link utilisation for real-time traffic flows in order to reduce queuing delay. Admission control uses a 2-phase commit protocol for handling QoS negotiation and adaptation. We also present a mechanism for deploying QoS-enabled dependable TCP services in this network. The primary-backup TCP replication mechanism is supported by the routing infrastructure and improves server deployment transparency compared to previous work. We illustrate application performance improvement with simulation results.