ppxscal/embedding_network huggingface dataset:
An agent based adaptive bandwidth allocation scheme for multimedia applications
Authors: S. S. Manvi, P. Venkataram
Venue: Journal of Systems and Software (2005)

Bandwidth allocation for multimedia applications in case of network congestion and failure poses technical challenges due to bursty and delay sensitive nature of the applications. The growth of multimedia services on Internet and the development of agent technology have made us to investigate new techniques for resolving the bandwidth issues in multimedia communications. Agent technology is emerging as a flexible promising solution for network resource management and QoS (Quality of Service) control in a distributed environment. In this paper, we propose an adaptive bandwidth allocation scheme for multimedia applications by deploying the static and mobile agents. It is a run-time allocation scheme that functions at the network nodes. This technique adaptively finds an alternate patchup route for every congested/failed link and reallocates the bandwidth for the affected multimedia applications. The designed method has been tested (analytical and simulation) with various network sizes and conditions. The results are presented to assess the performance and effectiveness of the approach. This work also demonstrates some of the benefits of the agent based schemes in providing flexibility, adaptability, software reusability, and maintainability.
GridIS: An Incentive-Based Grid Scheduling
Authors: Lijuan Xiao, Yanmin Zhu, Lionel M. Ni, Zhiwei Xu
Venue: Proceedings of the 19th IEEE International Parallel and Distributed Processing Symposium (IPDPS'05) - Papers - Volume 01 (2005)

In a grid computing environment, resources are autonomous, wide-area distributed, and what's more, they are usually not free. These unique characteristics make scheduling in a self-sustainable and market-like grid highly challenging. The goal of our work is to build such a global computational grid that every participant has enough incentive to stay and play in it. There are two parties in the grid: resource consumers and resource providers. Thus the performance objective of scheduling is two-fold: for consumers, high successful execution rate of jobs, and for providers, fair allocation of benefits. We propose an incentive-based grid scheduling, GridIS, which is composed of a P2P decentralized scheduling framework and incentive-based scheduling algorithms. Simulation results show that GridIS guarantees the incentive of every participant to a satisfying extent.
Efficient Solution of Optimal Control Problems Using Hybrid Systems
Authors: Mireille Broucke, Maria Domenica Di Benedetto, Stefano Di Gennaro, Alberto Sangiovanni-Vincentelli
Venue: SIAM Journal on Control and Optimization (2005)

We consider the synthesis of optimal controls for continuous feedback systems by recasting the problem to a hybrid optimal control problem: synthesize optimal enabling conditions for switching between locations in which the control is constant. An algorithmic solution is obtained by translating the hybrid automaton to a finite automaton using a bisimulation and formulating a dynamic programming problem with extra conditions to ensure non-Zenoness of trajectories. We show that the discrete value function converges to the viscosity solution of the Hamilton--Jacobi--Bellman equation as a discretization parameter tends to zero.
A Fast Multipole Method for Higher Order Vortex Panels in Two Dimensions
Authors: Prabhu Ramachandran, S. C. Rajan, M. Ramakrishna
Venue: SIAM Journal on Scientific Computing (2005)

Higher order panel methods are used to solve the Laplace equation in the presence of complex geometries. These methods are useful when globally accurate velocity or potential fields are desired as in the case of vortex based fluid flow solvers. This paper develops a fast multipole algorithm to compute velocity fields due to higher order, two-dimensional vortex panels. The technique is applied to panels having a cubic geometry and a linear distribution of vorticity. The results of the present method are compared with other available techniques.
Hierarchical location service for mobile ad-hoc networks
Authors: Wolfgang Kieß, Holger Füßler, Jörg Widmer, Martin Mauve
Venue: ACM SIGMOBILE Mobile Computing and Communications Review (2004)

Position-based routing has proven to be a scalable and efficient way for packet routing in mobile ad-hoc networks. To enable position-based routing, a node must be able to discover the location of the node it wants to communicate with. This task is typically accomplished by a location service. In this paper, we propose a novel location service called HLS (Hierarchical Location Service). HLS divides the area covered by the network into a hierarchy of regions. The top level region covers the complete network. A region is subdivided into several regions of the next lower level until the lowest level is reached. We call a lowest level region a cell. For a given node A, one specific cell is selected on each level of the hierarchy by means of hash function. As A changes its position it transmits position updates to these responsible cells. If another node wants to determine the position of A it uses the same hash function to determine the cells that may hold information about the position of A. It then proceeds to query the nodes in these cells in the order of the hierarchy until it receives a reply containing the current position of A. Because of its hierarchical approach HLS is highly scalable and particularly well suited for networks where communication partners tend to be close to each other. Due to the inherent scaling limitations of ad-hoc networks it is very likely that most ad hoc networks will display this property. Furthermore HLS is very robust to node mobility and node failures since it uses regions to select location servers and not a chain of mobile nodes as it is the case, e.g., for the well known Grid Location Service (GLS). We demonstrate these traits by providing extensive simulation data on the behaviour of HLS in a wide range of scenarios and by using GLS as a benchmark.
Fractal: A Mobile Code Based Framework for Dynamic Application Protocol Adaptation in Pervasive Computing
Authors: Hanping Lufei, Weisong Shi
Venue: Proceedings of the 19th IEEE International Parallel and Distributed Processing Symposium (IPDPS'05) - Papers - Volume 01 (2005)

The rapid growth of heterogeneous devices and diverse networks in our daily life, makes it is very difficult, if not impossible, to build a one-size-fits-all application or protocol, which can run well in such a dynamic environment. Adaptation has been considered as a general approach to address the mismatch problem between clients and servers; however, we envision that the missing part, which is also a big challenge, is how to inject and deploy adaptation functionality into the environment. In this paper we propose a novel application level protocol adaptation framework, Fractal, which uses the mobile code technology for protocol adaptation and leverages existing content distribution networks (CDN) for protocol adaptors (mobile codes) deployment. To the best of our knowledge, Fractal is the first application level protocol adaptation framework that considers the real deployment problem using mobile code and content distribution networks. To evaluate the proposed framework, we implement an adaptive communication optimization protocol by dynamically selecting four communication protocols, including Direct sending, Gzip, Bitmap, and Vary-sized blocking. In the comparison with the static and centralized protocol adaptation approaches, evaluation shows good results on both the client side and server side. For some clients, the total communication overhead reduces 41% compared with no protocol adaptation mechanism, and 14% compared with the static protocol adaptation approach.
Remote Physical Device Fingerprinting
Authors: Tadayoshi Kohno, Andre Broido, K. C. Claffy
Venue: Proceedings of the 2005 IEEE Symposium on Security and Privacy (2005)

We introduce the area of remote physical device fingerprinting, or fingerprinting a physical device, as opposed to an operating system or class of devices, remotely, and without the fingerprinted device's known cooperation. We accomplish this goal by exploiting small, microscopic deviations in device hardware: clock skews. Our techniques do not require any modification to the fingerprinted devices. Our techniques report consistent measurements when the measurer is thousands of miles, multiple hops, and tens of milliseconds away from the fingerprinted device, and when the fingerprinted device is connected to the Internet from different locations and via different access technologies. Further, one can apply our passive and semi-passive techniques when the fingerprinted device is behind a NAT or firewall, and also when the device's system time is maintained via NTP or SNTP. One can use our techniques to obtain information about whether two devices on the Internet, possibly shifted in time or IP addresses, are actually the same physical device. Example applications include: computer forensics; tracking, with some probability, a physical device as it connects to the Internet from different public access points; counting the number of devices behind a NAT even when the devices use constant or random IP IDs; remotely probing a block of addresses to determine if the addresses correspond to virtual hosts, e.g., as part of a virtual honeynet; and unanonymizing anonymized network traces.
Introduction to bioinformatics: Research Articles
Authors: David Fenstermacher
Venue: Journal of the American Society for Information Science and Technology (2005)

Bioinformatics is a multifaceted discipline combining many scientific fields including computational biology, statistics, mathematics, molecular biology, and genetics. Bioinformatics enables biomedical investigators to exploit existing and emerging computational technologies to seamlessly store, mine, retrieve, and analyze data from genomics and proteomics technologies. This is achieved by creating unified data models, standardizing data interfaces, developing structured vocabularies, generating new data visualization methods, and capturing detailed metadata that describes various aspects of the experimental design and analysis methods. Already there are a number of related undertakings that are dividing the field into more specialized groups. Clinical Bioinformatics and Biomedical Informatics are emerging as transitional fields to promote the utilization of genomics and proteomics data combined with medical history and demographic data towards personalized medicine, molecular diagnostics, pharmacogenomics and predicting outcomes of therapeutic interventions. The field of bioinformatics will continue to evolve through the incorporation of diverse technologies and methodologies that draw experts from disparate fields to create the latest computational and informational tools specifically design for the biomedical research enterprise. &copy; 2005 Wiley Periodicals, Inc.
Simulation of the California electric power market
Authors: Eileen Lowry
Venue: Journal of Computing Sciences in Colleges (2005)

California's recent electricity crisis has shown that an attempt to restructure the electric power market allowed firms to exploit market power by charging unprecedented wholesale prices. In the summer of 2000, wholesale electricity costs for the state of California rose from $2.04 billion in 1999 to $8.98 billion. Recent empirical studies have shown that market inefficiencies arose from inadequate protection against companies obtaining market power and in turn charging outrageous prices. This project models the varying degrees of market power, available capacity, and bottleneck transmission with a discrete event simulation program. After validating the flaws of the market through comparison with historical data, we shall use the simulation to analyze new, diverse stresses on the electric power market. Simulating California's electric power market will not only help prevent another crisis from occurring within California but will also assist other electric power markets, as market restructuring, electricity supply, and competitive pricing continue to be important issues throughout the country.
Blind Source Recovery in a State-Space Famework: Algorithms for Static and Dynamic Environments
Authors: Fathi M. Salem, Khurram Waheed, Gail Erten
Venue: Neural Processing Letters (2005)

This paper describes a generalized state space Blind Source Recovery (BSR) framework obtained by using the Kullback-Lieblar divergence as a performance functional and the application of optimization theory under the constraints of a feedforward state space structure. Update laws for both the non-linear and the linear dynamical systems have been derived for the domain of dynamic blind source recovery along both ordinary stochastic gradient and the Riemannian contra-variant gradient directions. The choice of the rich state space demixing network structure allows for the development of potent learning rules, capable of handling most filtering paradigms and convenient extension to non-linear models. Some particular filtering cases are subsequently derived from this general structure and are compared with material in the recent literature. Some of this reported work has also been implemented in dedicated hardware/software. An illustrative simulation example has been presented to demonstrate the online adaptation capabilities of the proposed algorithms.
Criminalising computer misconduct:Legal and philosophical concerns
Authors: Dr. Gregor Urbas
Venue: ACM SIGCAS Computers and Society (2004)

Computer misconduct (hacking, fraud, privacy breaches, pornography dissemination etc.) has been a part of computing and electronic communication since its early development. The process of criminalisation (enactment of laws creating specific offences covering these activities) has followed in a some what sporadic and uneven way, with notable discrepancies between jurisdictions both internationally and within countries. In Australia, there has been some movement towards uniformity with the enactment of the Cybercrime Act 2001 (Cth) and its equivalents in several States and Territories. Internati onally, there is gradual convergence towards models such as the Council of Europe&iquest;s Convention on Cybercrime. However, the philosophical concerns behind such legislation are not always clear or uniform. Interests sought to be protected from computer misconduct range from traditional concerns of crim inal law (physical safety, personal property, public order etc.) through to larger-scale and more abstract concerns (national infrastructure security and system integrity). This paper assesses legal and philosophical aspects of Australian and comparable computer crime legislation. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Matching with PROSAC " Progressive Sample Consensus
Authors: Ondrej Chum, Jiri Matas
Venue: Proceedings of the 2005 IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR'05) - Volume 1 - Volume 01 (2005)

A new robust matching method is proposed. The Progressive Sample Consensus (PROSAC) algorithm exploits the linear ordering defined on the set of correspondences by a similarity function used in establishing tentative correspondences. Unlike RANSAC, which treats all correspondences equally and draws random samples uniformly from the full set, PROSAC samples are drawn from progressively larger sets of top-ranked correspondences. Under the mild assumption that the similarity measure predicts correctness of a match better than random guessing, we show that PROSAC achieves large computational savings. Experiments demonstrate it is often significantly faster (up to more than hundred times) than RANSAC. For the derived size of the sampled set of correspondences as a function of the number of samples already drawn, PROSAC converges towards RANSAC in the worst case. The power of the method is demonstrated on wide-baseline matching problems.
Fast and efficient searches for effective optimization-phase sequences
Authors: Prasad A. Kulkarni, Stephen R. Hines, David B. Whalley, Jason D. Hiser, Jack W. Davidson, Douglas L. Jones
Venue: ACM Transactions on Architecture and Code Optimization (TACO) (2005)

It has long been known that a fixed ordering of optimization phases will not produce the best code for every application. One approach for addressing this phase-ordering problem is to use an evolutionary algorithm to search for a specific sequence of phases for each module or function. While such searches have been shown to produce more efficient code, the approach can be extremely slow because the application is compiled and possibly executed to evaluate each sequence's effectiveness. Consequently, evolutionary or iterative compilation schemes have been promoted for compilation systems targeting embedded applications where meeting strict constraints on execution time, code size, and power consumption is paramount and longer compilation times may be tolerated in the final stage of development, when an application is compiled one last time and embedded in a product. Unfortunately, even for small embedded applications, the search process can take many hours or even days making the approach less attractive to developers. In this paper, we describe two complementary general approaches for achieving faster searches for effective optimization sequences when using a genetic algorithm. The first approach reduces the search time by avoiding unnecessary executions of the application when possible. Results indicate search time reductions of 62&percnt;, on average, often reducing searches from hours to minutes. The second approach modifies the search so fewer generations are required to achieve the same results. Measurements show this approach decreases the average number of required generations by 59&percnt;. These improvements have the potential for making evolutionary compilation a viable choice for tuning embedded applications.
Book review: Knowledge Representation: An Approach to Artificial Intelligence By T.J.M. Bench-Capon (Academic Press, London, 1990)
Venue: ACM SIGART Bulletin (1991)

Who needs yet another introductory text on artificial intelligence? The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Fuzzy Image Segmentation Combing Ring and Elliptic Shaped Clustering Algorithms
Authors: M. Ameer Ali, Laurence S. Dooley, Gour C. Karmakar
Venue: Proceedings of the International Conference on Information Technology: Coding and Computing (ITCC'05) - Volume II - Volume 02 (2005)

Results from any existing clustering algorithm that are used for segmentation are highly sensitive to features that limit their generalization. Shape is one important attribute of an object. The detection and separation of an object using fuzzy ring-shaped clustering (FKR) and elliptic ring-shaped clustering (FKE) already exists in the literature. Not all real objects however, are ring or elliptical in shape, so to address these issues, this paper introduces a new shape-based algorithm, called fuzzy image segmentation combing ring and elliptic shaped clustering algorithms (FCRE) by merging the initial segmented results produced by FKR and FKE. The distribution of unclassified pixels is performed by connectedness and fuzzy c-means (FCM) using a combination of pixel intensity and normalized pixel location. Both qualitative and quantitative analysis of the results for different varieties of images proves the superiority of the proposed FCRE algorithm compared with both FKR and FKE.
A compiler for multiple memory models: Research Articles
Authors: S. P. Midkiff, J. Lee, D. A. Padua
Venue: Concurrency and Computation: Practice Experience (2004)

The design of consistency models for both hardware and software is a difficult task. For a programming language, it is particularly difficult because the target audience for a high-level programming language is much wider than the target audience for a machine language, making usability a more important criterion. Exacerbating this problem is the reality that the programming language community has little experience designing programming language consistency models, and therefore each new attempt is very much a voyage into uncharted territory. A concrete example of the difficulties of the task is the current Java Memory Model. Although designed to be easy to use by Java programmers, it is poorly understood and at least one common idiom (the &lsquo;double check idiom&rsquo;) to exploit the model is unsafe. In this paper, we describe the design of an optimizing Java compiler that will accept either as input or as an interface implementation a consistency model for the code to be compiled. The compiler will use Shasha and Snir's delay set analysis, and our CSSA program representation to provide a canonical representation for the effects of different consistency models on optimizations and analysis. The compiler will serve as a testbed to prototype new memory models, and to measure the effects of different memory models on program performance. Copyright &copy; 2004 John Wiley & Sons, Ltd.
Quantitative Evaluation of a Novel Image Segmentation Algorithm
Authors: Francisco J. Estrada, Allan D. Jepson
Venue: Proceedings of the 2005 IEEE Computer Society Conference on Computer Vision and Pattern Recognition (CVPR'05) - Volume 2 - Volume 02 (2005)

We present a quantitative evaluation of SE-MinCut, a novel segmentation algorithm based on spectral embedding and minimum cut. We use human segmentations from the Berkeley Segmentation Database as ground truth and propose suitable measures to evaluate segmentation quality. With these measures we generate precision/recall curves for SE-MinCut and three of the leading segmentation algorithms: Mean-Shift, Normalized Cuts, and the Local Variation algorithm. These curves characterize the performance of each algorithm over a range of input parameters. We compare the precision/recall curves for the four algorithms and show segmented images that support the conclusions obtained from the quantitative evaluation.
Undirected ST-connectivity in log-space
Authors: Omer Reingold
Venue: Proceedings of the thirty-seventh annual ACM symposium on Theory of computing (2005)

We present a deterministic, log-space algorithm that solves st-connectivity in undirected graphs. The previous bound on the space complexity of undirected st-connectivity was log4/3 obtained by Armoni, Ta-Shma, Wigderson and Zhou [9]. As undirected st-connectivity is complete for the class of problems solvable by symmetric, non-deterministic, log-space computations (the class SL), this algorithm implies that SL = L (where L is the class of problems solvable by deterministic log-space computations). Independent of our work (and using different techniques), Trifonov [45] has presented an O(log n log log n)-space, deterministic algorithm for undirected st-connectivity.Our algorithm also implies a way to construct in log-space a fixed sequence of directions that guides a deterministic walk through all of the vertices of any connected graph. Specifically, we give log-space constructible universal-traversal sequences for graphs with restricted labelling and log-space constructible universal-exploration sequences for general graphs.