ppxscal/embedding_network huggingface dataset:
Optimal Rate Allocation for Rate-Constrained Applications in Wireless Sensor Networks
Authors: Chun Lung Lin, Hai Fu Wang, Sheng Kai Chang, Jia Shung Wang
Venue: Proceedings of the 4th IEEE international conference on Distributed Computing in Sensor Systems (2008)

This paper addresses the optimal rate allocation (ORA) problem as follows: given a target bit rate constraint, determine an optimal rate allocation among sensors such that the overall distortion of the reproduction data is minimized. Optimal rate allocation algorithms are proposed to determine the coding bit rate of each sensor in single hop and multihop sensor networks, given a target rate constraint. Extensive simulations are conducted by using temperature readings of the real world dataset. The results show that at low bit rates the optimal rate allocation improves about 2.745 dB on the uniform rate allocation in terms of SNR, and improves nearly 7.602 in terms of MSE. Spatial-temporal range queries are also evaluated to confirm that our approach is often sufficient to provide approximate statistics for range queries.
A Formal Approach to Detect Functionally Irrelevant Barriers in MPI Programs
Authors: Subodh Sharma, Sarvani Vakkalanka, Ganesh Gopalakrishnan, Robert M. Kirby, Rajeev Thakur, William Gropp
Venue: Proceedings of the 15th European PVM/MPI Users' Group Meeting on Recent Advances in Parallel Virtual Machine and Message Passing Interface (2008)

We examine the unsolved problem of automatically and efficiently detecting functionally irrelevant barriers in MPI programs. A functionally irrelevant barrier is a set of MPI_Barrier calls, one per MPI process, such that their removal does not alter the overall MPI communication structure of the program. Static analysis methods are incapable of solving this problem, as MPI programs can compute many quantities at runtime, including send targets, receive sources, tags, and communicators, and also can have data-dependent control flows. We offer an algorithm called Fib to solve this problem based on dynamic (runtime) analysis. Fib applies to MPI programs that employ 24 widely used two-sided MPI operations. We show that it is sufficient to detect barrier calls whose removal causes a wildcard receive statement placed before or after a barrier to now begin matching a send statement with which it did not match before. Fib determines whether a barrier becomes relevant in any interleaving of the MPI processes of a given MPI program. Since the number of interleavings can grow exponentially with the number of processes, Fib employs a sound method to drastically reduce this number, by computing only the relevant interleavings. We show that many MPI programs do not have data dependent control flows, thus making the results of Fib applicable to all the input data the program can accept.
A Formalism for Recongurability Analysis in Distributed Non-Blocking Components
Authors: Mahdi Niamanesh, Rasool Jalili
Venue: Proceedings of the 2008 The 28th International Conference on Distributed Computing Systems Workshops (2008)

Reconfigurability for a component of a distributed component-based system means ability to replace the component with a new one, in presence of the other components. In this context, substitutability and compatibility of components should be analyzed. In this paper, we use I/O-Constraint Automata to model behavior of components and propose enough formalism for substitutability and compatibility analysis. We show that in the context of distributed non-blocking components, there is a relation weaker than usual simulation relation in automata theory for notion of substitutability. We illustrate the relation between substitutability and compatibility to reason about the recongurability of a component.
Transistor-Level Evolution of Digital Circuits Using a Special Circuit Simulator
Authors: Luděk Žaloudek, Lukáš Sekanina
Venue: Proceedings of the 8th international conference on Evolvable Systems: From Biology to Hardware (2008)

An evolutionary algorithm is used to design digital circuits at the transistor level. In particular, various static CMOS circuits with up to four inputs were evolved. The increase in the complexity of evolved circuits wrt existing circuits evolved at the transistor level is primarily caused by two phenomena: the usage of a specialized circuit simulator and restriction of the search space. Because we restricted the search space to the set of "reasonable designs" we could employ imperfect, but very fast circuit simulation. The usage of proposed simulator allowed exploring more candidate designs than a conventional Spice-based approach. However, in some cases, an incorrect behavior was detected after validation of evolved circuits using Spice simulator.
Navigation and Search in 3D Visualizations of Large Unstructured Photo Collections: An Empirical Study
Authors: Olivier Christmann, Noëlle Carbonell
Venue: Proceedings of the 10th international conference on Visual Information Systems: Web-Based Visual Information Search and Management (2008)

We present an empirical study which aims at assessing the effects of dynamic 3D visualizations of randomly ordered photo collections on visual search effectiveness, efficiency and comfort. 20 participants performed visual search tasks in collections of about 1000 colour photos using 2 perspective views of a vertical cylinder: thumbnails were displayed on its lateral surface either on the inside (IV) or on the outside (OV). Scrolling IV suggests locomotion in an immersive virtual space while scrolling OV suggests manipulation of a 3D virtual object. Perspective distortions in OV "channel" gaze towards the centre of the screen while IV permits of freer gaze movements.A majority of participants (12) performed noticeably better with one view (IV or OV) than with the other. Animation and perspective distortions influenced visual exploration strategies (16 participants). Preferences, which varied across participants, were mainly motivated by individual visual capabili-ties; the influence of interaction metaphors was marginal. Qualitative analyses of participants' behaviours suggest that IV has the potential to support spatial memory. These results indicate that adaptable perspective views may facilitate and improve visual search in unstructured picture collections.
Taming the torrent: a practical approach to reducing cross-isp traffic in peer-to-peer systems
Authors: David R. Choffnes, Fabián E. Bustamante
Venue: ACM SIGCOMM Computer Communication Review (2008)

Peer-to-peer (P2P) systems, which provide a variety of popular services, such as file sharing, video streaming and voice-over-IP, contribute a significant portion of today's Internet traffic. By building overlay networks that are oblivious to the underlying Internet topology and routing, these systems have become one of the greatest traffic-engineering challenges for Internet Service Providers (ISPs) and the source of costly data traffic flows. In an attempt to reduce these operational costs, ISPs have tried to shape, block or otherwise limit P2P traffic, much to the chagrin of their subscribers, who consistently finds ways to eschew these controls or simply switch providers. In this paper, we present the design, deployment and evaluation of an approach to reducing this costly cross-ISP traffic without sacrificing system performance. Our approach recycles network views gathered at low cost from content distribution networks to drive biased neighbor selection without any path monitoring or probing. Using results collected from a deployment in BitTorrent with over 120,000 users in nearly 3,000 networks, we show that our lightweight approach significantly reduces cross-ISP traffic and, over 33% of the time, it selects peers along paths that are within a single autonomous system (AS). Further, we find that our system locates peers along paths that have two orders of magnitude lower latency and 30% lower loss rates than those picked at random, and that these high-quality paths can lead to significant improvements in transfer rates. In challenged settings where peers are overloaded in terms of available bandwidth, our approach provides 31% average download-rate improvement; in environments with large available bandwidth, it increases download rates by 207% on average (and improves median rates by 883%
An Improved Algorithm for Detecting a Singleton Attractor in a Boolean Network Consisting of AND/OR Nodes
Authors: Takeyuki Tamura, Tatsuya Akutsu
Venue: Proceedings of the 3rd international conference on Algebraic Biology (2008)

Detection of a singleton attractor, which is also called a fixed point, is known to be NP-hard even for AND/OR BNs (i.e., BNs consisting of AND/OR nodes), where the Boolean network (BN) is a mathematical model of genetic networks and singleton attractors correspond to steady states. In our recent paper, we developed an O(1.787 n ) time algorithm for detecting a singleton attractor of a given AND/OR BN where n is the number of nodes. In this paper, we present an O(1.757 n ) time algorithm with which we succeeded in improving the above algorithm.
Oce@Nyd: a new tailorable groupware for digital media collection for underwater virtual environments
Authors: Nader Cheaib, Samir Otmane, Malik Mallem, Alain Dinis, Nicolas Fies
Venue: Proceedings of the 3rd international conference on Digital Interactive Media in Entertainment and Arts (2008)

This paper presents an innovative scientific approach for the design of a tailorable groupware architecture devoted to the collection of Digital media for underwater virtual environments. The proposed approach is based on Web services and software agent technologies. The aim is to design a flexible and reconfigurable collaborative platform to allow users, on one hand, to collect and manipulate via the Internet different digital media (image, video, audio, 3D models, etc.), and on the other hand, certain services can be manually or dynamically integrated as new behaviours, where existing groupware systems often offer a limited and rigid set of functionalities, hence limiting collaboration's performance. This work is applied on a R&D project, DIGITAL OCEAN, a new media system obtained by the integration of three multimedia products currently being developed, and is conceived to enable the general public to discover, online, underwater virtual environments. We present this ongoing project and the scientific background behind it, taking in consideration technical aspects as well as the project's perspectives on the global market, and emphasizing the innovation it brings, where it opens to the multimedia and audiovisual industries a new space that is still virgin, the underwater space.
Density Based Fuzzy Membership Functions in the Context of Geocomputation
Authors: Victor Lobo, Fernando Bação, Miguel Loureiro
Venue: Proceedings of the 7th international conference on Computational Science, Part II (2007)

Geocomputation has a long tradition in dealing with fuzzyness in different contexts, most notably in the challenges created by the representation of geographic space in digital form. Geocomputation tools should be able to address the imminent continuous nature of geo phenomena, and its accompanying fuzzyness. Fuzzy Set Theory allows partial memberships of entities to concepts with non-crisp boundaries. In general, the application of fuzzy methods is distance-based and for that reason is insensible to changes in density. In this paper a new method for defining density-based fuzzy membership functions is proposed. The method automatically determines fuzzy membership coefficients based on the distribution density of data. The density estimation is done using a Self-Organizing Map (SOM). The proposed method can be used to accurately describe clusters of data which are not well characterized using distance methods. We show the advantage of the proposed method over traditional distance-based membership functions.
Optimal determination of partial transmission ratios for four-step helical gearboxes with first and third step double gear-sets for minimal mass of gears
Authors: Vu Ngoc Pi
Venue: Proceedings of the WSEAS International Conference on Applied Computing Conference (2008)

This paper introduces a new study on the applications of optimization and regression analysis techniques for optimal determination of partial transmission ratios of four-step helical gearboxes with first and third step double gear-sets in order to get the minimal mass of gears. In the study, based on the moment equilibrium condition of a mechanic system including gear units and their regular resistance condition, an optimization program for determining the partial ratios of the gearboxes is carried out. From the results of the optimization program, explicit models for calculation of the partial ratios are introduced by using regression analysis. Using these models, the calculation of the partial ratios becomes accurate and simple.
An Invariant-Based Method for the Analysis of Declarative Model-to-Model Transformations
Authors: Jordi Cabot, Robert Clarisó, Esther Guerra, Juan Lara
Venue: Proceedings of the 11th international conference on Model Driven Engineering Languages and Systems (2008)

In this paper we propose a method to derive OCL invariants from declarative specifications of model-to-model transformations. In particular we consider two of the most prominent approaches for specifying such transformations: Triple Graph Grammars and QVT. Once the specification is expressed in the form of invariants, the transformation developer can use such description to verify properties of the original transformation (e.g. whether it defines a total, surjective or injective function), and to validate the transformation by the automatic generation of valid pairs of source and target models.
Mining Conditional Cardinality Patterns for Data Warehouse Query Optimization
Authors: Mikołaj Morzy, Marcin Krystek
Venue: Proceedings of the 10th international conference on Data Warehousing and Knowledge Discovery (2008)

Data mining algorithms are often embedded in more complex systems, serving as the provider of data for internal decision making within these systems. In this paper we address an interesting problem of using data mining techniques for database query optimization. We introduce the concept of conditional cardinality patterns and design an algorithm to compute the required values for a given database schema. However applicable to any database system, our solution is best suited for data warehouse environments due to the special characteristics of both database schemata being used and queries being asked. We verify our proposal experimentally by running our algorithm against the state-of-the-art database query optimizer. The results of conducted experiments show that our algorithm outperforms traditional cost-based query optimizer with respect to the accuracy of cardinality estimation for a wide range of queries.
Video completion and synthesis
Authors: Chunxia Xiao
Venue: Computer Animation and Virtual Worlds (2008)

This paper presents a new exemplar-based framework for video completion, allowing aesthetically pleasing completion of large space-time holes. We regard video completion as a discrete global optimization on a 3D graph embedded in the space-time video volume. We introduce a new objective function which enforces global spatio-temporal consistency among patches that fill the hole and surrounding it, in terms of both color similarity and motion similarity. The optimization is solved by a novel algorithm, called weighted priority belief propagation (BP), which alleviates the problems of slow convergence and intolerable storage size when using the standard BP. This objective function can also handle video texture synthesis by extending an input video texture to a larger texture region. Experiments on a wide variety of video examples with complex dynamic scenes demonstrate the advantages of our method over existing techniques: salient structures and motion information are much better restored. Copyright &copy; 2008 John Wiley & Sons, Ltd.
A Global Contour-Grouping Algorithm Based on Spectral Clustering
Authors: Hui Yin, Siwei Luo, Yaping Huang
Venue: Proceedings of the 5th international symposium on Neural Networks: Advances in Neural Networks, Part II (2008)

Perceptual organization has two essential factors that affect the grouping result directly: how to extract grouping cues and how to grouping. In this paper, a global contour-grouping algorithm based on spectral clustering is presented. First, a new grouping cue called wavelet edge is obtained in multi-scale space, which not only has the property of intensity and direction, but also has the property of singularity measured by lipschitz exponent. Thus grouping cues carry the information of both areas and edges. Secondly, a global grouping approach is presented by use of spectral clustering that has no limitation of neighborhood. Furthermore, the Gestalt principles are used to optimize the grouping result by adding penalty item in iterative process. The experiments show that this algorithm will be effective on condition that the singularities of the edges that belong to one object are equal or close, especially for partially occluded object.
Medical Data Integration and the Semantic Annotation of Medical Protocols
Authors: Rafael Berlanga, Ernesto Jimenez-Ruiz, Victoria Nebot, David Manset, Andrew Branson, Tamas Hauer, Richard McClatchey, Dmitry Rogulin, Jetendr Shamdasani, Sonja Zillner, Joerg Freund
Venue: Proceedings of the 2008 21st IEEE International Symposium on Computer-Based Medical Systems (2008)

The integration of heterogeneous biomedical information is one important step towards providing the level of personalization required in the next generation of healthcare provision. In order to provide the computer-based decision support systems needed to access this integrated healthcare information it will be necessary to handle the semantics of (amongst other things) medical protocols. The EC FP6 Health-e-Child project aims to develop an integrated healthcare platform for European paediatrics and decision support tools to access personalized health information. This paper introduces both the integrated data model in the Health-e-Child project and through a case study using the brain tumour protocols it demonstrates the semantic annotation of patient data acquired in the project using UMLS as the primary source of semantic data.
Echo State Networks for Online Prediction of Movement Data --- Comparing Investigations
Authors: Sven Hellbach, Sören Strauss, Julian P. Eggert, Edgar Körner, Horst-Michael Gross
Venue: Proceedings of the 18th international conference on Artificial Neural Networks, Part I (2008)

This paper's intention is to adapt Echo State Networks to problems being faced in the field of Human-Robot Interactions. The idea is to predict movement data of persons moving in the local surroundings by understanding it as time series. The prediction is done using a black box model, which means that no further information is used than the past of the trajectory itself. This means the suggested approaches are able to adapt to different situations. For experiments, real movement data as well as synthetical trajectories (sine and Lorenz-attractor) are used. Echo State Networks are compared to other state-of-the-art time series analysis algorithms, such as Local Modeling, Cluster Weighted Modeling, Echo State Networks, and Autoregressive Models. Since mobile robots highly depend on real-time application.
A Cost-Effective Mobile Video Streaming with an Adaptive Control of Inter-packet Delays
Authors: Youn-Sik Hong, Jun-Sik Hong
Venue: Proceedings of the international conference on Computational Science and Its Applications, Part II (2008)

In a recent VoD application, a stationary VoD server delivers video stream to a mobile device, particularly PDA, over wireless. Typically, the sending rate at the server is faster than the playback rate at the handheld device. Therefore, it can't receive streaming video as possible as the sending rate even if there is no congestion and extremely low BER over wireless. Our objective is to develop a simple cost effective rate control scheme using a buffer level at a mobile device. We classify the buffer at a mobile device into three distinct states depending on its level (occupancy). For each of these states a different rate control is to be applied.
Detecting Topological Change Using a Wireless Sensor Network
Authors: Christopher Farah, Cheng Zhong, Michael Worboys, Silvia Nittel
Venue: Proceedings of the 5th international conference on Geographic Information Science (2008)

Dynamic geographic phenomena, such as forest fires and oil spills, can have dire environmental, sociopolitical, and economic consequences. Mitigating, if not preventing such events requires the use of advanced spatio-temporal information systems. One such system that has gained widespread interest is the wireless sensor network (WSN), a deployment of sensor nodes --- tiny untethered computing devices, which run on batteries and are equipped with one or more commercial off-the-shelf or custom-made sensors and a radio transceiver. This research deals with initial attempts to detect topological changes to geographic phenomena by an environmentally deployed wireless sensor network (WSN). After providing the mathematical and technical preliminaries, we define topological change and present in-network algorithms to detect such changes and also, to manage the WSN's resources efficiently. The algorithms are compared against a resource-heavy continuous monitoring approach via simulation. The results show that two topological changes, hole loss and hole formation, can be correctly detected in-network and that energy is greatly saved by our event-driven approach. In future work, we hope to test the algorithms over a broader range of topological changes and to relax some of the network assumptions.
Theory and simulation of the acoustic noise propagation
Authors: Cardei Petru
Venue: Proceedings of the 9th WSEAS International Conference on Acoustics & Music: Theory & Applications (2008)

This paper try to compare the theoretic results in the acoustic noise propagation with the experimental data and with the simulation techniques, using by the very useful software programs. Are formulate some suggestion for improve the experimental formulae using for noise propagation simulation.
Improving fairness in a WRED-based DiffServ network: A fluid-flow approach
Authors: Mario Barbera, Alfio Lombardo, Giovanni Schembra, Andrea Trecarichi
Venue: Performance Evaluation (2008)

The DiffServ architecture has been proposed as a scalable approach for upgrading the Internet, adding service differentiation functionalities. However, several aspects of this architecture still have to be analyzed and solved. For this reason, network designers need to be provided with tools which are able to estimate the average behavior of a DiffServ network with a high level of accuracy and in a short time. In this paper a fluid-flow model of a DiffServ network supporting Assured Forwarding Per-Hop Behavior (PHB) and loaded with TCP flows is proposed. At the edge of the network, two rate three color markers (TRTCM) are employed as profile meters, while within the network core routers implement a Weighted RED (WRED) buffer management mechanism. In order to demonstrate the high accuracy of the proposed model, a comparison between model and simulation results is performed, taking into account not just a bottleneck link, but a complex network topology. The proposed analytical framework is then used to analyze the impact of several factors on the fair sharing of network resources between traffic aggregates with the same traffic profile, and to achieve some guidelines for WRED parameter settings with the aim of reducing unfairness.