ppxscal/embedding_network huggingface dataset:
Fault-Tolerant Extension of Hypercube for Secure and Reliable Group Communications
Authors: Maria Striki, John S. Baras, Kyriakos Manousakis
Venue: Proceedings of the Seventh International Conference on Networking (2008)

Securing group communications in resource constrained, infrastructure-less Mobile Ad Hoc Networks (MANETs) has become one of the most challenging research directions in the areas of wireless networking and security. MANETs are emerging as the desired environment for an increasing number of commercial and military applications, addressing also an increasing number of users. Security on the other hand, is becoming an indispensable requirement of our modern life for all these applications. The inherent limitations of MANETs impose major difficulties on establishing a suitable secure group communications framework. We contribute to the latter by extending Hypercube, an existing key agreement (KA) scheme - all parties contribute equally to the group key - to tolerate multiple member failures with low cost. We achieve this by enhancing Hypercube with a novel adaptively proactive algorithm. Members are assumed to be already authenticated via some underlying mechanism and we only focus on the design and analysis of a fault-tolerant scheme. Our algorithm has been evaluated and compared with the existing approach. Through our analysis and simulations we demonstrate its superiority in terms of robustness and efficiency.
Efficient provenance storage
Authors: Adriane P. Chapman, H. V. Jagadish, Prakash Ramanan
Venue: Proceedings of the 2008 ACM SIGMOD international conference on Management of data (2008)

As the world is increasingly networked and digitized, the data we store has more and more frequently been chopped, baked, diced and stewed. In consequence, there is an increasing need to store and manage provenance for each data item stored in a database, describing exactly where it came from, and what manipulations have been applied to it. Storage of the complete provenance of each data item can become prohibitively expensive. In this paper, we identify important properties of provenance that can be used to considerably reduce the amount of storage required. We identify three different techniques: a family of factorization processes and two methods based on inheritance, to decrease the amount of storage required for provenance. We have used the techniques described in this work to significantly reduce the provenance storage costs associated with constructing MiMI [22], a warehouse of data regarding protein interactions, as well as two provenance stores, Karma [31] and PReServ [20], produced through workflow execution. In these real provenance sets, we were able to reduce the size of the provenance by up to a factor of 20. Additionally, we show that this reduced store can be queried efficiently and further that incremental changes can be made inexpensively.
Jim Gray's Tandem contributions
Authors: John Nauman Wendy Bartlett
Venue: ACM SIGMOD Record (2008)

This paper discusses the contributions and accomplishments of Jim Gray while he was at Tandem Computers between 1980 and the early 1990s.
Teach Scheme, reach Java: introducing object-oriented programming without drowning in syntax
Authors: Stephen Bloch
Venue: Journal of Computing Sciences in Colleges (2008)

We'll discuss a multi-lingual approach to the first year of programming, starting in a simple, consistent language like Scheme to get across essential concepts (e.g. variables, functions, parameters, data types, composition, testing, conditionals, classes with fields, polymorphism, recursion) and a principled methodology of programming. We'll demonstrate how the same topics can be subsequently covered in a more mainstream, but more complex, language such as Java, taking advantage of students' preparation during the Scheme phase of the course. Participants will be invited to a week-long, NSF-funded workshop in Summer 2008, which goes into much more depth on technical, classroom, and curriculum issues [TSRJ08].
A Distributed Trust Management Based on Authorizing Negotiation in Open and Dynamic Environments
Authors: Shangyuan Guan, Xiaoshe Dong, Weiguo Wu, Yiduo Mei, Guofu Feng
Venue: Proceedings of the 22nd International Conference on Advanced Information Networking and Applications (2008)

Trust has been recognized as an important factor for information security in open and dynamic environments, such as Internet applications, p2p systems etc. On the basis of analyzing existing trust management systems, this paper proposes a Distributed Trust Management based on Authorizing Negotiation (DTMAN). DTMAN presents a number of innovative features. First, it can authorize strangers by using authorizing negotiation, so it is very suitable for open and dynamic environments. Second, a high efficient algorithm for compliance checking is developed to support DTMAN, whose time complexity and space complexity are both O(n) (where n is the cardinality of the set of authorization credentials). The experimental result shows that the algorithm of DTMAN is more efficient than others.
A new solution encoding for solving the resource-constrained project scheduling problem with genetic algorithms
Authors: Javier Alcaraz, Concepción Maroto
Venue: Proceedings of the 4th WSEAS International Conference on Applied Mathematics and Computer Science (2005)

The problem considered in this work is the well known and widely studied Resource-Constrained Project Scheduling Problem (RCPSP), denoted as m,1/cpm/Cmax (Herroelen et al. [8]) or PS/prec/Cmax (Brucker et al. [4]). Several different heuristic, metaheuristic and hybrid techniques have been developed to solve this combinatorial optimization problem. We have developed an efficient, competitive and robust genetic algorithm, based on a new solutions encoding, knowledge specific genetic operators and an improvement mechanism. We have compared this algorithm with the best algorithms published so far, using the standard benchmark of PSPLIB. The preliminary results show the excellent performance of our algorithm. The algorithm has not been completely calibrated yet, but once this task has been completed, these results will be surely improved.
Optimizing relevance and revenue in ad search: a query substitution approach
Authors: Filip Radlinski, Andrei Broder, Peter Ciccolo, Evgeniy Gabrilovich, Vanja Josifovski, Lance Riedel
Venue: Proceedings of the 31st annual international ACM SIGIR conference on Research and development in information retrieval (2008)

The primary business model behind Web search is based on textual advertising, where contextually relevant ads are displayed alongside search results. We address the problem of selecting these ads so that they are both relevant to the queries and profitable to the search engine, showing that optimizing ad relevance and revenue is not equivalent. Selecting the best ads that satisfy these constraints also naturally incurs high computational costs, and time constraints can lead to reduced relevance and profitability. We propose a novel two-stage approach, which conducts most of the analysis ahead of time. An offine preprocessing phase leverages additional knowledge that is impractical to use in real time, and rewrites frequent queries in a way that subsequently facilitates fast and accurate online matching. Empirical evaluation shows that our method optimized for relevance matches a state-of-the-art method while improving expected revenue. When optimizing for revenue, we see even more substantial improvements in expected revenue.
An Efficient Soft Tissue Characterization Method for Haptic Rendering of Soft Tissue Deformation in Medical Simulation
Authors: Bummo Ahn, Jung Kim
Venue: Proceedings of the 2007 Frontiers in the Convergence of Bioscience and Information Technologies (2007)

The modeling of soft tissue behavior is essential in haptic rendering for virtual reality based medical simulators, which provide a safe and objective medium for training medical personnel. This paper presents a measuring device, modeling and effective characterization method of soft tissue's material properties. Experiments were conducted on five porcine livers using an indentation device and ramp-and-hold trajectory. The soft tissue was assumed to be a continuous, incompressible, homogeneous and isotropic solid and a nonlinear constitutive model based on the observation of the force-displacement behavior of soft tissues. The constitutive model was fitted to the experimental data using the Levenberg-Marquardt optimization algorithm combined with a three-dimensional nonlinear finite element simulation. Scripting software was used to automatically characterize the mechanical properties and to repeat the FE simulation until the simulated and experimental responses matched.
Interactive and Personalized Services for an Open IMS-Based IPTV Infrastructure
Authors: Oliver Friedrich, Robert Seeliger, Stefan Arbanowski
Venue: Proceedings of the Seventh International Conference on Networking (2008)

In this paper a proof of concept infrastructure for the delivery of IMS-based IPTV services driven by the IPTV enabled FOKUS Open IMS infrastructure will be presented. Asthe different Standard Development Organizations (SDOs) will release frameworks for standardized IPTV by the end of thisyear the FOKUS Media Interoperability Lab (MIL) represents one of the world’s first real world test beds for these kind ofservices. This has been achieved by actively guiding the different SDOs work with a focus on ETSI TISPAN. On top of this framework different personalized and interactive services have been implemented to show the predominance and advantages of IMS-based IPTV solutions compared to other mainly black boxapproaches.
Evaluation of the Learning of Scientific English in Podcasting PCs, MP3s, and MP4s Scenarios
Authors: Siew-Rong Wu
Venue: Proceedings of the 2008 IEEE International Conference on Sensor Networks, Ubiquitous, and Trustworthy Computing (sutc 2008) (2008)

To examine the effects of the use of podcasting in the learning of scientific English in the university setting, this study was conducted in two English scientific listening and speaking classes taught by the researcher-teacher at a medical university in Taipei, TAIWAN from November to December 2007. Podcasts on science were used as learning materials. Learning outcome assessments include concept-mapping, oral tests, and scientific essay writing. Students' use of tools: PCs, MP3s, and MP4s, their frequency, duration, and location of use, and motivation and learning attitude were assessed by questionnaires. Experimental results show that due to the activation of higher-order thinking and cognitive engagement, deep learning was facilitated in students' learning processes. Besides, a preference of using MP3s for the learning of scientific English and a preference of using MP4s for deep learning of science and scientific English were identified in this study.
Alternative data storage solution for mobile messaging services
Authors: David C. C. Ong, Rytis Sileika, Souheil Khaddaj, Radouane Oudrhiri
Venue: Mobile Information Systems (2007)

In recent years, mobile devices have become relatively more powerful with additional features which have the capability to provide multimedia streaming. Better, faster and more reliable data storage solutions in the mobile messaging platform have become more essential with these additional improvements. The existing mobile messaging infrastructure, in particular the data storage platform has become less proficient in coping with the increased demand for its services. This demand especially in the mobile messaging area (i.e. SMS - Short Messaging Service, MMS - Multimedia Messaging Service), which may well exceeded 250,000 requests per second, means that the need to evaluate competing data management systems has become not only necessary but essential. This paper presents an evaluation of SMS and MMS platforms using different database management systems - DBMS and recommends the best data management strategies for these platforms.
A Geographical Observation System based on P2P Agents
Authors: Yuuichi Teranishi, Hirokazu Tanaka, Yoshimasa Ishi, Mikio Yoshida
Venue: Proceedings of the 2008 Sixth Annual IEEE International Conference on Pervasive Computing and Communications (2008)

In this paper, a novel design and implementation of a geographical observation system based on P2P agents is described. We propose sensor agent architecture to realize efficient and real-time notifications of sensor information. In this architecture, sensors act as agents and send updated notification messages to the observer agents which satisfy specified conditions by making use of multiple overlays. These features are implemented on P2P agent software ‘PIAX’. In this implementation, Web browsers and cellular phones can act as observer agents.
A design framework for scalar feedback in MIMO broadcast channels
Authors: Ruben de Francisco, Dirk T. M. Slock
Venue: EURASIP Journal on Advances in Signal Processing (2008)

Joint linear beamforming and scheduling are performed in a system where limited feedback is present at the transmitter side. The feedback conveyed by each user to the base station consists of channel direction information (CDI) based on a predetermined codebook and a scalar metric with channel quality information (CQI) used to perform user scheduling. In this paper, we present a design framework for scalar feedback in MIMO broadcast channels with limited feedback. An approximation on the sum rate is provided for the proposed family of metrics, which is validated through simulations. For a given number of active users and average SNR conditions, the base station is able to update certain transmission parameters in order to maximize the sum-rate function. On the other hand, the proposed sum-rate function provides a means of simple comparison between transmission schemes and scalar feedback techniques. Particularly, the sum rate of SDMA and time division multiple access (TDMA) is compared in the following extreme regimes: large number of users, high SNR, and low SNR. Simulations are provided to illustrate the performance of various scalar feedback techniques based on the proposed design framework.
Routing in outer space: fair traffic load in multi-hop wireless networks
Authors: Alessandro Mei, Julinda Stefa
Venue: Proceedings of the 9th ACM international symposium on Mobile ad hoc networking and computing (2008)

In this paper we consider security-related and energy-efficiency issues in multi-hop wireless networks. We start our work from the observation, known in the literature, that shortest path routing creates congested areas in multi-hop wireless networks. These areas are critical - they generate both security and energy efficiency issues. We attack these problems and set out routing in outer space, a new routing mechanism that transforms any shortest path routing protocol (or approximated versions of it) into a new protocol that does not create congested areas, does not have the associated security-related issues, and does not encourage selfish positioning. Moreover, the network lives longer of the same network using the original routing protocol (in spite of using more energy globally), and dies more gracefully.
A novel approach for integrated pushpull converter using ZVT-PWM technique in DC UPS
Authors: R. Dhanasekaran, M. Rajaram, Rajesh Bhupathi
Venue: Proceedings of the 2nd WSEAS International Conference on Electronics, Control and Signal Processing (2003)

This paper is a novel approach for integrated push pull converter performing the combined functions of Uninterruptible Power Supply (UPS) and Switch Mode Power Supply (SMPS) using Zero - Voltage Transition (ZVT) Pulse Width Modulation (PWM) Boost and Buck converters. The integrated push pull converters has high voltage main power input supply and low voltage back up supply. The output is a DC obtained from main input via the push pull converter during normal operation and back up battery via another push pull converter at the failure of the main supply. High conversion efficiency is achieved in normal, backup and charging modes as there is a only double dc-dc voltage conversion in each mode. The converter circuit is simple with four switching transistors, a relay for switching mode. For the converter circuit, boost and buck converters used at the secondary side of the push pull transformer using a new class of ZVT-PWM is proposed where both transistor and rectifier operate with zero voltage switching and subjected to minimum voltage and current stresses. These approaches offer substantial improvement in efficiency, size and cost over the conventional cascade of UPS and SMPS due to less number of voltage conversions, high frequency switching and removal of design redundancy. The design and simulation results of the above-proposed approaches are presented.
Exploiting Wikipedia for Directional Inferential Text Similarity
Authors: Leong Chee Wee, Samer Hassan
Venue: Proceedings of the Fifth International Conference on Information Technology: New Generations (2008)

In natural languages, variability of semantic expression refers to the situation where the same meaning can be inferred from different words or texts. Given that many natural language processing tasks nowadays (e.g. question answering, information retrieval, document summarization) often model this variability by requiring a specific targetmeaning to be inferred from different text variants, it is helpful to capture text similarity in a directional manner to serve such inference needs. In this paper, we show how Wikipedia can be used as a semantic resource to build a directional inferential similarity metric between words, and subsequently, texts. Through experiments, we show that our Wikipedia-based metric performs significantly better when applied to a standard evaluation dataset, with a reduction in error rate of 16.1% over the random metric baseline.
Velodrome: a sound and complete dynamic atomicity checker for multithreaded programs
Authors: Cormac Flanagan, Stephen N. Freund, Jaeheon Yi
Venue: Proceedings of the 2008 ACM SIGPLAN conference on Programming language design and implementation (2008)

Atomicity is a fundamental correctness property in multithreaded programs, both because atomic code blocks are amenable to sequential reasoning (which significantly simplifies correctness arguments), and because atomicity violations often reveal defects in a program's synchronization structure. Unfortunately, all atomicity analyses developed to date are incomplete in that they may yield false alarms on correctly synchronized programs, which limits their usefulness. We present the first dynamic analysis for atomicity that is both sound and complete. The analysis reasons about the exact dependencies between operations in the observed trace of the target program, and it reports error messages if and only if the observed trace is not conflict-serializable. Despite this significant increase in precision, the performance and coverage of our analysis is competitive with earlier incomplete dynamic analyses for atomicity.
XML Profile for Distributed Real Time Systems
Authors: Polly M. Poon, Tharam S. Dillon, Elizabeth Chang, Ling Feng
Venue: Proceedings of the 2008 11th IEEE Symposium on Object Oriented Real-Time Distributed Computing (2008)

In this paper, we describe a XML based profile for modeling the semantics of real time systems. We aim to use Real Time Markup Language (RTML) to provide a comprehensive description of temporal properties for the use in distributed systems communication. RTML is derived from a number of specifications including OMG UML Profile in Schedulability, Performance, and Time. In this paper, we discuss the technique that was used to develop RTML semantic model and the important concepts in RTML.
Policy-based BGP-control architecture for inter-AS routing adjustment
Authors: Osamu Akashi, Kensuke Fukuda, Toshio Hirotsu, Toshiharu Sugawara
Venue: Computer Communications (2008)

Unexpected temporal and spatial changes of interdomain routing paths often lead to the necessity of on-demand routing adjustment among independently managed ASs. For resolving this problem, we have developed a BGP-control architecture called Virtual Router (VR) for controlling conventional BGP routers from outside without any protocol extensions. The VR combined with a multi-agent system (MAS) can be applied for the inter-AS routing adjustment for transit ISPs and their customer ASs. This architecture makes incremental deployment possible. The VR controls interdomain routing by dynamically changing forwarding paths among alternative BGP entries in multiple border routers. Each agent, which interprets a policy description for acquiring and analyzing network status, exchanges interdomain routing adjustment preferences when an adjustment is required, and coordinates where and how to change routing on the basis of feedback. Evaluation results indicate the validity and effectiveness of the basic design of our system in some control scenarios, where an AS tries to balance inbound traffic flowing via neighboring BGP peers.
A compositional Petri net translation of general &#x03c0;-calculus terms
Authors: Raymond Devillers, Hanna Klaudel, Maciej Koutny
Venue: Formal Aspects of Computing (2008)

We propose a finite structural translation of possibly recursive &#x03c0;-calculus terms into Petri nets. This is achieved by using high-level nets together with an equivalence on markings in order to model entering into recursive calls, which do not need to be guarded. We view a computing system as consisting of a main program (&#x03c0;-calculus term) together with procedure declarations (recursive definitions of &#x03c0;-calculus identifiers). The control structure of these components is represented using disjoint high-level Petri nets, one for the main program and one for each of the procedure declarations. The program is executed once, while each procedure can be invoked several times (even concurrently), each such invocation being uniquely identified by structured tokens which correspond to the sequence of recursive calls along the execution path leading to that invocation.
Feature selection algorithms in classification problems: an experimental evaluation
Authors: A. Salappa, M. Doumpos, C. Zopounidis
Venue: Optimization Methods Software (2007)

Feature selection (FS) is a significant topic for the development of efficient pattern recognition systems. FS refers to the selection of the most appropriate subset of features that describes (adequately) a given classification task. The objective of the present paper is to perform a thorough analysis of the performance and efficiency of feature selection algorithms (FSAs). The analysis covers a variety of important issues with respect to the functionality of FSAs, such as: (a) their ability to identify relevant features, (b) the performance of the classification models developed on a reduced set of features, (c) the reduction in the number of features and (d) the interactions between different FSAs with the techniques used to develop a classification model. The analysis considers a variety of FSAs and classification methods.
E-learning with Intelligent Agents
Authors: Maria Ganzha
Venue: IEEE Distributed Systems Online (2008)

A review of Designing Distributed Learning Environments with Intelligent Software Agents, Fuhua Oscar Lin, ed.