ppxscal/embedding_network huggingface dataset:
Practical Byzantine Group Communication
Authors: Vadim Drabkin, Roy Friedman, Alon Kama
Venue: Proceedings of the 26th IEEE International Conference on Distributed Computing Systems (2006)

This paper presents an adaptation of the JazzEnsemble group communication system that enables it to tolerate Byzantine failures. The work emphasizes scalability and good performance in the normal case, i.e., when there are no failures, while providing strong semantics to the application. The paper presents the main concepts and protocols that enable the Byzantine tolerant version of JazzEnsemble to obtain these goals. In particular, this includes fuzzy mute and fuzzy verbose failure detectors, an efficient Byzantine vector consensus protocol, and a novel Byzantine uniform broadcast protocol, as well as modifications at each layer of the system to overcome potential Byzantine attacks. Additionally, high-level protocols only rely on the oral messages model, and thus messages need to be signed only once at a low level of the system. Finally, the paper presents an extensive performance evaluation, which demonstrates the system's scalability and efficiency, and is used to analyze the sources of performance degradation associated with various aspects of overcoming Byzantine failures.
Application of Middleware Technique in Web of Flood Forecasting System with Multiple Models
Authors: Huang Mincong, Xie Jiancang, Cai Yang, Wang Ni, Zhang Yongjin
Venue: Proceedings of the 2006 International Conference on Hybrid Information Technology - Volume 01 (2006)

According to the J2EE criteria, a framework based on the middleware technique and model-viewcontroller (MVC) design pattern are introduced to establish a flood control system in a Web domain which are flexible enough for future extension, algorithm improvement and upgrade with new hydrologic models. The Xinanjiang and the tank models are adopted as the hydrological models to investigate the applicability of the proposed technology. Components for a flood forecasting system based on the Xinanjiang and the Tank models were developed under an IE browser. The forecasting system was tested in a small watershed and it is indicates that the Xinanjiang model performed better than the tank model.
Minimizing DNF Formulas and AC^0_d Circuits Given a Truth Table
Authors: Eric Allender, Lisa Hellerstein, Paul McCabe, Toniann Pitassi, Michael Saks
Venue: Proceedings of the 21st Annual IEEE Conference on Computational Complexity (2006)

For circuit classes R, the fundamental computational problem Min-R asks for the minimum R-size of a Boolean function presented as a truth table. Prominent examples of this problem include Min-DNF, which asks whether a given Boolean function presented as a truth table has a k-term DNF, and Min-Circuit (also called MCSP), which asks whether a Boolean function presented as a truth table has a size k Boolean circuit. We present a new reduction proving that Min-DNF is NP-complete. It is significantly simpler than the known reduction of Masek [31], which is from Circuit-SAT.
An Efficient Clustering Scheme through Estimate in Centralized Hierarchical Routing Protocol
Authors: Jin-Mook Kim, Hyeon-Kyu Joo, Seong-Sik Hong, Woo-Hyun Ahn, Hwang-Bin Ryou
Venue: Proceedings of the 2006 International Conference on Hybrid Information Technology - Volume 02 (2006)

Nodes in WSN(Wireless Sensor Network) have limited energy. Once they are deployed, it is difficult to supply additional energy. Therefore the routing is most important for using energy efficiently in WSN. The routing protocols of this sensor network have two types: Directed Diffusion and SPIN such as Flat routing protocol, and LEACH (Low-Energy Adaptive Clustering Hierarchy) and LEACH-C (LEACH-Centralized) such as Hierarchical routing protocol. In this paper, we present remaining energy predictable method using computing consumption of nodes and cluster head node from first round to next round for solving LEACH-C problem that all nodes must send current energy level and own location to base station at each round in configuration. When using proposed method through simulation, we can extend the life time of network and lessen total energy of network as reducing a number of communications
Fuzzy Description Logic Programs under the Answer Set Semantics for the Semantic Web
Authors: Thomas Lukasiewicz
Venue: Proceedings of the Second International Conference on Rules and Rule Markup Languages for the Semantic Web (2006)

Vagueness and imprecision abound in multimedia information processing and retrieval. In this paper, towards dealing with vagueness and imprecision in the reasoning layers of the Semantic Web, we present an approach to fuzzy description logic programs under the answer set semantics. We generalize normal description logic programs (dl-programs) under the answer set semantics by fuzzy vagueness and imprecision. We define a canonical semantics of positive and stratified fuzzy dl-programs in terms of a unique least model and iterative least models, respectively. We then define the answer set semantics of general fuzzy dlprograms, and show in particular that all answer sets of a fuzzy dl-program are minimal models, and that the answer set semantics of positive and stratified fuzzy dl-programs coincides with their canonical least model and iterative least model semantics, respectively. Furthermore, we also provide a characterization of the canonical semantics of positive and stratified fuzzy dl-programs in terms of a fixpoint and an iterative fixpoint semantics, respectively.
Approximate maximum weight branchings
Authors: Amitabha Bagchi, Ankur Bhargava, Torsten Suel
Venue: Information Processing Letters (2006)

We consider a special subgraph of a weighted directed graph: one comprising only the k heaviest edges incoming to each vertex. We show that the maximum weight branching in this subgraph closely approximates the maximum weight branching in the original graph. Specifically, it is within a factor of k/(k + 1). Our interest in finding branchings in this subgraph is motivated by a data compression application in which calculating edge weights is expensive but estimating which are the heaviest k incoming edges is easy. An additional benefit is that since algorithms for finding branchings run in time linear in the number of edges our results imply faster algorithms although we sacrifice optimality by a small factor. We also extend our results to the case of edge-disjoint branchings of maximum weight and to maximum weight spanning forests.
Mining progressive confident rules
Authors: Minghua Zhang, Wynne Hsu, Mong Li Lee
Venue: Proceedings of the 12th ACM SIGKDD international conference on Knowledge discovery and data mining (2006)

Many real world objects have states that change over time. By tracking the state sequences of these objects, we can study their behavior and take preventive measures before they reach some undesirable states. In this paper, we propose a new kind of pattern called progressive confident rules to describe sequences of states with an increasing confidence that lead to a particular end state. We give a formal definition of progressive confident rules and their concise set. We devise pruning strategies to reduce the enormous search space. Experiment result shows that the proposed algorithm is efficient and scalable. We also demonstrate the application of progressive confident rules in classification.
On the existence and stability of the periodic solution in the Cohen-Grossberg neural network with time delay and high-order terms
Authors: Chen Wu, Jiong Ruan, Wei Lin
Venue: Applied Mathematics and Computation (2006)

Qualitative property for a class of the delayed Cohen-Grossberg neural network with high-order terms is investigated in the paper. Periodic solution is rigorously proved to be exist in this class of models by means of the Gains and Mawhin's continuation theorem. In addition, sufficient conditions are established for both global exponential and asymptotical stability of the existent periodic solution with the aid of the Lyapunov functional and the theory of linear matrix inequality (LMI). Finally, two examples with their numerical simulations are provided to illustrate the possible application of our criteria.
Reconfigurable Path Planning for an Autonomous Unmanned Aerial Vehicle
Authors: Mariusz Wzorek, Patrick Doherty
Venue: Proceedings of the 2006 International Conference on Hybrid Information Technology - Volume 02 (2006)

In this paper, we present a motion planning framework for a fully deployed autonomous unmanned aerial vehicle which integrates two sample-based motion planning techniques, Probabilistic Roadmaps and Rapidly Exploring Random Trees. Additionally, we incorporate dynamic reconfigurability into the framework by integrating the motion planners with the control kernel of the UAV in a novel manner with little modification to the original algorithms. The framework has been verified through simulation and in actual flight. Empirical results show that these techniques used with such a framework offer a surprisingly efficient method for dynamically reconfiguring a motion plan based on unforeseen contingencies which may arise during the execution of a plan. The framework is generic and can be used for additional platforms.
Analysis methodology: are we done?
Authors: Sigrün Andradóttir, David Goldsman, Lee W. Schruben, Bruce W. Schmeiser, Enver Yücesan
Venue: Proceedings of the 37th conference on Winter simulation (2005)

Since 1967, the Winter Simulation Conference has been a forum for the introduction of innovative approaches to effectively analyze discrete-event simulation experiments. The goal of this panel is to bring together key contributors to analysis methodology research in order to clarify areas that they think are essentially complete, and identify areas that need more work. In doing so, we hope to help provide direction to younger researchers looking for the "right" problems to work on.
Military applications of agent-based simulations
Authors: Thomas M. Cioppa, Thomas W. Lucas, Susan M. Sanchez
Venue: Proceedings of the 36th conference on Winter simulation (2004)

There continues to be increasing interest from a broad range of disciplines in agent-based and artificial life simulations. This includes the Department of Defense---which uses simulations heavily in its decision making process. Indeed, military conflicts can have many attributes that are consistent with complex adaptive systems---such as many entities interacting with some degree of autonomy, each of which is continually making decisions to satisfy a variety of sometimes conflicting objectives. In this paper, we present three applications of agent-based simulations used to analyze military problems. The first uses the MANA model to explore the ability of the U.S. Army's network-based Future Force to perform with degraded communications. The second studies how unmanned surface vehicles can be used in force protection missions with the Pythagoras model. The last example examines the standard Army squad size with an integrated effort using MANA, Pythagoras, and the high-resolution simulation JANUS.
Clairvoyant Non-Preemptive EDF Scheduling
Authors: Cecilia Ekelin
Venue: Proceedings of the 18th Euromicro Conference on Real-Time Systems (2006)

It is well-known that although EDF is optimal for preemptive systems this is not the case in non-preemptive ones. The problem is that for a non-preemptive scheduler to be optimal, it must sometimes use inserted idle times. In this paper we show how the performance of non-preemptive EDF can be improved by using a form of lookahead that identifies when idle time insertion is necessary. Experiments show that this modification increases the number of schedulable task sets by up to 100%. Furthermore, by using a form of lazy evaluation the algorithm runs in which is the same as plain EDF.
Investigation on the Dynamic Behavior of High-Velocity Feed System Directly Driven by a Linear Motor
Authors: Shuhong Xiao, Changli Zha
Venue: Proceedings of the First International Conference on Innovative Computing, Information and Control - Volume 1 (2006)

High-velocity feed system directly driven by a thrustful linear motor is a novel driving style for CNC machining tool feed system. It eliminates all mechanical transmission elements. The linear motor's primary and secondary parts are assembled into the worktable and the machine bed respectively to directly drive the machine table to realize linear feed. But this kind of transmission is very sensitive to disturbances. The cutting force and moving mass are both direct disturbances to the system. This paper analyzes the method to calculate the dynamic rigidity based on the system's control model, discusses the factors which influence the behavior of the system, and presents main measures to improve dynamic behavior. Moving mass estimator is designed according to the system. The paper realizes the online mass estimation and compensation. Simulation on the practical system shows the online mass estimation and compensation takes an approving control effect for the system.
A Dynamic Mobility Histogram Construction Method Based on Markov Chains
Authors: Yoshiharu Ishikawa, Yoji Machida, Hiroyuki Kitagawa
Venue: Proceedings of the 18th International Conference on Scientific and Statistical Database Management (2006)

With the recent progress of spatial information technologies and communication technologies, it has become easier to track positions of a large number of moving objects in real-time. Mobility statistics plays an important role in the interactive analysis of a large collection of moving objects trajectories and its use of movement pattern prediction. The development of an effective mobility statistics measure and its efficient computation method are critical issues. Thus, we propose an approach for constructing a mobility histogram to summarize a number of moving object trajectories. The histogram is based on a mobility statistics model called the Markov chain model. To facilitate an interactive analysis performed by a user, we provide a mobility histogram data cube-like logical representation and support an OLAP-style analysis. Since trajectory data is often received continuously as a trajectory stream, we have to support dynamic histogram construction and maintenance. We introduce a tree structure as the physical representation of a histogram and present histogram construction and maintenance methods that work efficiently within the given upperbound size. We evaluate the performance and the precision of the proposed method by means of experiments.
Dynamic load balancing across mirrored multimedia servers
Authors: A. Matthur, P. Mundur
Venue: Proceedings of the 2003 International Conference on Multimedia and Expo - Volume 1 (2003)

The purpose of this paper is to present protocols for efficient load balancing across replicated multimedia servers in a metropolitan area network. Current multimedia infrastructures, even when they use mirrored servers, do not have standardized load balancing schemes. Existing schemes frequently require participation from the clients in balancing the load across the servers efficiently. We propose two protocols in this paper for fair load balancing without any client-side processing being required. Neither protocol requires any change to the network-level infrastructure. Using network packet loss and packet transmission delay as the chief metrics, we show the effectiveness of the protocols through extensive simulations.
uClassroom: Expanding Awareness in Classroom To Ubiquitous Teaching and Learning
Authors: Shoji Kajita, Kenji Mase
Venue: Proceedings of the Fourth IEEE International Workshop on Wireless, Mobile and Ubiquitous Technology in Education (2006)

This paper describes the concept of Ubiquitous Classroom and its implementation that enables us to expand "the awareness among faculty and students in classroom to ubiquitous teaching and learning environments. As we have experienced, the awareness among faculty and students in a real class is crucial to know students' learning situations, and faculty adapts a way of teaching to them in order to maximize the outcome of teaching and learning through a class. This kind of awareness is also crucial even if faculty supports students' learning activities outside classroom through Course management System (CMS). However, the conventional Web-based CMSs used in higher educational institutions are too limited to realize such awareness because of Web-browser's functional and security restrictions. We addressed this problem by developing eclipse RCP (Rich Client Platform) based uDesktop and Context Infrastructure integrated with Sakai Collaboration and Learning Environment as an institution-wide and production-level information infrastructure system. We will show the effectiveness of "awareness through iPod integration used in English language learning.
Analysis of a Multiscale Discontinuous Galerkin Method for Convection-Diffusion Problems
Authors: A. Buffa, T. J. R. Hughes, G. Sangalli
Venue: SIAM Journal on Numerical Analysis (2006)

We study a multiscale discontinuous Galerkin method introduced in [T. J. R. Hughes, G. Scovazzi, P. Bochev, and A. Buffa, Comput. Meth. Appl. Mech. Engrg., 195 (2006), pp. 2761-2787] that reduces the computational complexity of the discontinuous Galerkin method, seemingly without adversely affecting the quality of results. For a stabilized variant we are able to obtain the same error estimates for the convection-diffusion equation as for the usual discontinuous Galerkin method. We assess the stability of the unstabilized case numerically and find that the inf-sup constant is positive, bounded uniformly away from zero, and very similar to that for the usual discontinuous Galerkin method.
A robust moving mesh finite volume method applied to 1D hyperbolic conservation laws from magnetohydrodynamics
Authors: A. van Dam, P. A. Zegeling
Venue: Journal of Computational Physics (2006)

In this paper we describe a one-dimensional adaptive moving mesh method and its application to hyperbolic conservation laws from magnetohydrodynamics (MHD). The method is robust, because it employs automatic control of mesh adaptation when a new model is considered, without manually-set parameters. Adaptive meshes are a common tool for increasing the accuracy and reducing computational costs when solving time-dependent partial differential equations (PDEs). Mesh points are moved towards locations where they are needed the most. To obtain a time-dependent adaptive mesh, monitor functions are used to automatically 'monitor' the importance of the various parts of the domain, by assigning a 'weight'-value to each location. Based on the equidistribution principle, all mesh points are distributed according to their assigned weights. We use a sophisticated monitor function that tracks both small, local phenomena as well as large shocks in the same solution. The combination of the moving mesh method and a high-resolution finite volume solver for hyperbolic PDEs yields a serious gain in accuracy at relatively no extra costs. The results of several numerical experiments including comparisons with h-refinement are presented, which cover many intriguing aspects typifying nonlinear magneto-fluid dynamics, with higher accuracy than often seen in similar publications.
Posterior Corpus Callosum and Interhemispheric Transfer of Somatosensory Information: An fMRI and Neuropsychological Study of a Partially Callosotomized Patient
Authors: Mara Fabri, Gabriele Polonara, Maria Del Pesce, Angelo Quattrini, Ugo Salvolini, Tullio Manzoni
Venue: Journal of Cognitive Neuroscience (2001)

Interhemispheric somatosensory transfer was studied by functional magnetic resonance imaging (fMRI) and neuropsychological tests in a patient who underwent resection of the corpus callosum (CC) for drug-resistant epilepsy in two stages. The first resection involved the anterior half of the body of CC and the second, its posterior half and the splenium. For the fMRI study, the hand was stimulated with a rough sponge. The neuropsychological tests included: Tactile Naming Test (TNT), Same-Different Recognition Test (SDRT), and Tactile Finger Localization Test (intra- and intermanual tasks, TFLT). The patient was studied 1 week before and then 6 months and 1 year after the second surgery. Before this operation, unilateral tactile stimulation of either hand activated contralaterally the first (SI) and second (SII) somatosensory areas and the posterior parietal (PP) cortex, and SII and PP cortex ipsilaterally. All three tests were performed without errors. In both postoperative sessions, somatosensory activation was observed in contralateral SI, SII, and PP cortex, but not in ipsilateral SII and PP cortex. Performance was 100&percnt; correct in the TNT for the right hand, but below chance for the left; in the other tests, it was below chance except for TFLT in the intramanual task. This case provides the direct demonstration that activation of SII and PP cortex to stimulation of the ipsilateral hand and normal interhemispheric transfer of tactile information require the integrity of the posterior body of the CC.
The electronic and atomic structure of SrTiO3, BaTiO3, and PbTiO3(001) surfaces: Ab initio DFT/HF hybrid calculations
Authors: S. Piskunov, E. A. Kotomin, E. Heifets
Venue: Microelectronic Engineering (2005)

In our first-principles study, the electronic properties of the (001) surfaces of three key perovskite crystals, namely SrTiO"3 (STO), BaTiO"3 (BTO), and PbTiO"3 (PTO), have been calculated by means of the density functional theory (DFT) using the exchange-correlation functional containing ''hybrid'' of the non-local Hartree-Fock (HF) exchange, DFT exchange, and Generalized Gradient Approximation (GGA) correlation functionals, commonly known as B3PW. Such a technique allows us to get the optical bulk band gap very close to experiment unlike previous calculations of perovskites. Special attention is paid to careful calculations of the surface rumpling and change of the distances between three near-surface planes. We compare results with available experimental data. The calculated electronic band structures for relaxed surfaces show no splitting of surface electronic states from the upper valence bands for the AO-terminated (001) surfaces (consisting of Ti 4d and O 2p orbitals) and the presence of Pb 6s orbitals in the top of the PbTiO"3 valence band. This is important for the treatment of the electronic structure of surface defects on ABO"3 perovskite surfaces as well as for adsorption and surface diffusion of atoms and small molecules (e.g. O, O"2), relevant for catalysis and fuel cell applications.
An approximation scheme for the effective Hamiltonian and applications
Authors: M. Rorro
Venue: Applied Numerical Mathematics (2006)

We introduce an approximation for first order Hamilton-Jacobi equations with a convex Hamiltonian periodic in the space variable. To this end we use a first order semi-Lagrangian scheme to compute a solution of the so-called cell problem and the related effective Hamiltonian. The scheme can also be interpreted as a discrete version of the Lax-Oleinik representation formula for the exact viscosity solution of the time-dependent problem. The information included in the solutions of the cell problem and in the effective Hamiltonian is exploited for the approximation of the Aubry set. We prove some properties of the scheme and illustrate the effectiveness of our approximation by several tests in dimension 1 and 2.
Types and Effects for Secure Service Orchestration
Authors: Massimo Bartoletti, Pierpaolo Degano, Gian Luigi Ferrari
Venue: Proceedings of the 19th IEEE workshop on Computer Security Foundations (2006)

A distributed calculus is proposed for describing networks of services. We model service interaction through a call-by-property invocation mechanism, by specifying the security constraints that make their composition safe. A static approach is then proposed to determine how to compose services and guarantee that their execution is always secure, without resorting to any dynamic check.