ppxscal/embedding_network huggingface dataset:
Framework for Defining Model Language Metamodels for CASE Tools
Authors: Iván García-Magariño, Jorge J. Gómez-Sanz
Venue: Proceedings of the 2008 5th International Workshop on Model-based Methodologies for Pervasive and Embedded Software (2008)

This paper presents a framework for defining metamodels. The main goal of this framework is to achieve the model interchange among CASE tools. This framework adds the CASE tools issues to the definitions of the model languages. The presented framework contains four internal metamodels. Firstly, a metamodel specifies the abstract syntax of the model language. Secondly, another metamodel specifies the particular elements for the connection-based languages. Thirdly, a metamodel specifies the spatial information. At last, a metamodel defines the necessary elements for the CASE tools. Each internal metamodel can be changed without having effect on the others. These four internal metamodels can be combined in several ways (denoted as configurations). Each configuration has its particular scope. The presented framework has been already used for defining the INGENIAS language and modernising the INGENIAS Development Kit (IDK). The presented framework is compared to the UML Diagram Interchange (UML-DI) specification and other relevant works.
Designing and evaluating interleaving decompressing and virus scanning in a stream-based mail proxy
Authors: Ying-Dar Lin, Szu-Hao Chen, Po-Ching Lin, Yuan-Cheng Lai
Venue: Journal of Systems and Software (2008)

A storage-based anti-virus access gateway is not scalable because it stores the entire mail under processing. This work designs and evaluates a stream-based mail proxy constructed from several open-source packages. This proxy processes mail in segments, and interleaves MIME parsing, decoding, decompressing and virus scanning. It is seven times faster than the storage-based one on forwarding, three times faster on virus scanning, and twice as faster on decompressing plus virus scanning. This proxy can keep nearly constant memory usage and work without disks, while the storage-based one requires memory and disk space proportional to the number of clients and the mail size.
Using genetic programming for artificial neural network development and simplification
Authors: Daniel Rivero, Julian Dorado, Juan Rabuñal, Alejandro Pazos
Venue: Proceedings of the 5th WSEAS International Conference on Computational Intelligence, Man-Machine Systems and Cybernetics (2006)

The creation process of Artificial Neural Networks (ANNs) used to be quite slow and the human expert had to test several architectures until finding the one that achieves the best results for the solution of a certain problem. This work presents a new technique that uses Genetic Programming (GP) for automatically creating ANNs. This technique also allows the obtaining of simplified networks with few neurons for solving the problem. In order to measure the performance of the system and to compare the results with other ANN generation and training methods with Evolutionary Computation (EC) techniques, several tests were performed with problems based on some of the most used test databases. The results of those comparisons showed that the system achieved good results comparable with already existing techniques and, in most of the cases, they worked better than those techniques.
Intelligent MANET Routing System
Authors: N. H. Saeed, M. F. Abbod, H. S. Al-Raweshidy
Venue: Proceedings of the 22nd International Conference on Advanced Information Networking and Applications - Workshops (2008)

In any Mobile Ad Hoc Network, a single routing system is in use during communication time without considering the MANET context, in spite the fact that MANET context affects the routing protocol performance. Changes in the MANET context lead to changes in the routing protocol behaviour for better or worse performance. This paper introduces a novel intelligent Mobile Ad Hoc Network routing system which is adaptable to the variations in the MANET context as the intelligent module selects four important parameters which indicate the changes in the network context. This intelligent system acquires the network’s performance and then selects the optimum routing protocol that gives the best performance according to network context, such as: number and mobility of nodes. This module suggests the optimum network context for that situation.
Scalable MPEG-4 Video Transmission Using Video Quality Metrics
Authors: Chetan Bhadricha, Benny Bing
Venue: Proceedings of the Communication Networks and Services Research Conference (2008)

Video streaming applications place high bandwidth requirements on the network, even for efficiently compressed MPEG-4 and H.264 videos. There is a need for these applications to reduce the use of bandwidth, especially when operated on bandwidth-constrained access networks involving cable, DSL, and wireless. However, a direct reduction in allocated bandwidth to a video may have an adverse effect on its visual quality. In addition, the high bit rate variability associated with MPEG-4 compressed video makes it difficult to determine the appropriate level of bandwidth reduction for such videos. MPEG-4 encodes videos as a sequence of I, P, and B-frames, with B-frames containing the least amount of information. Furthermore, the encoded sequence contains forward and backward references for the predictive coding of P and B-frames, which can be used to predict these frames when there is a frame loss. We exploit this feature to selectively drop B-frames to reduce the bandwidth requirements and bit rate variability. We also employ the frame-size (content-independent metric) and the relative PSNR (content-dependent metric) to achieve scalable video transmission. It will be shown via an actual network setup that substantial bandwidth savings can be achieved using the proposed methods and in the majority of the cases, this can be done without sacrificing video quality during playback.
3D conforming power diagrams for radial LGR in CPG reservoir grids
Authors: C. Bennis, H. Borouchaki, N. Flandrin
Venue: Engineering with Computers (2008)

Mesh generation becomes a crucial step in reservoir flow simulation of new generation. The mesh must faithfully represent the architecture of the reservoir and its heterogeneity. In (Flandrin et al. in IJNME 65(10):1639&#x2013;1672, 2006) a three-dimensional hybrid mesh model was proposed to capture the radial characteristics of the flow around the wells. In this hybrid mesh, the reservoir is described by a non-uniform Cartesian structured mesh and the drainage areas around the wells are represented by structured radial circular meshes. Unstructured polyhedral meshes are used to connect these two kinds of structured grids. The construction of these transition meshes is based on 3D power diagrams (Aurenhammer in SIAM J Comput 16(1):78&#x2013;96, 1987) to ensure finite volume properties such as mesh conformity, dual orthogonality and cell convexity. In this paper, we propose an extension of this hybrid model to the case where the reservoir is described by a corner point geometry (CPG) grid. At first, the CPG grid is mapped, in a reference space, into a non-uniform Cartesian grid by minimizing the mapping deformation. Then, a hybrid mesh is generated in this reference space using the previous method. Finally, this mesh is mapped back into the real space. Some quality criterions are introduced to measure and improve the quality of the polyhedral transition mesh.
Stochastic formulation of SPICE-type electronic circuit simulation with polynomial chaos
Authors: Kai Strunz, Qianli Su
Venue: ACM Transactions on Modeling and Computer Simulation (TOMACS) (2008)

A methodology for efficient tolerance analysis of electronic circuits based on nonsampling stochastic simulation of transients is formulated, implemented, and validated. We model the stochastic behavior of all quantities that are subject to tolerance spectrally with polynomial chaos. A library of stochastic models of linear and nonlinear circuit elements is created. In analogy to the deterministic implementation of the SPICE electronic circuit simulator, the overall stochastic circuit model is obtained using nodal analysis. In the proposed case studies, we analyze the influence of device tolerance on the response of a lowpass filter, the impact of temperature variability on the output of an amplifier, and the effect of changes of the load of a diode bridge on the probability density function of the output voltage. The case studies demonstrate that the novel methodology is computationally faster than the Monte Carlo method and more accurate and flexible than the root-sum-square method. This makes the stochastic circuit simulator, referred to as PolySPICE, a compelling candidate for the tolerance study of reliability-critical electronic circuits.
A computer-based test to raise awareness of disability issues
Authors: John Gray, Gill Harrison, Andrea Gorra, Jakki Sheridan-Ross, Janet Finlay
Venue: ACM SIGCSE Bulletin (2008)

The purpose of this poster is to share our experience of a staff development tool that has been developed to raise awareness amongst staff about issues that students with disabilities might face. A computer-based test has been created as a training tool to raise awareness among university academic staff of some common experiences faced by people with visual, mobility, hearing and cognitive difficulties when using a computer [1]. The development team is based at Leeds Metropolitan University and is part of a UK centrally-funded "Centre for Excellence in Teaching and Learning" (CETL) [2], in collaboration with the Universities of Durham, Newcastle and Leeds. The Centre is devoted to promoting "Active Learning in Computing" (ALiC) [3] and is the only CETL within the Computer Science academic area. This test simulates experiences of disabled students who use computers and take computer-based tests, and provides advice and guidance to university teaching staff on how they may best cater for the needs of such students. The poster presents the reasons for creating such a tool in such a format, its structure and content.
On spanning trees and walks of low maximum degree
Authors: Daniel P. Sanders, Yue Zhao
Venue: Journal of Graph Theory (2001)

This article uses the discharging method to obtain the best possible results that a 3-connected graph embeddable on a surface of Euler characteristic &chi;&thinsp;&le;&thinsp;-46 has a spanning tree of maximum degree at most $\lceil {{8-2\chi}\over{3}}\rceil$ and a closed, spanning walk meetting each vertex at most $\lceil {{6-2\chi}\over{3}}\rceil$ times. Each of these results is shown to be best possible. &copy; 2001 John Wiley & Sons, Inc. J Graph Theory 36: 67&ndash;74, 2001
Model checking Duration Calculus: a practical approach
Authors: Roland Meyer, Johannes Faber, Jochen Hoenicke, Andrey Rybalchenko
Venue: Formal Aspects of Computing (2008)

Model checking of real-time systems against Duration Calculus (DC) specifications requires the translation of DC formulae into automata-based semantics. The existing algorithms provide a limited DC coverage and do not support compositional verification. We propose a translation algorithm that advances the applicability of model checking tools to realistic applications. Our algorithm significantly extends the subset of DC that can be checked automatically. The central part of the algorithm is the automatic decomposition of DC specifications into sub-properties that can be verified independently. The decomposition is based on a novel distributive law for DC. We implemented the algorithm in a tool chain for the automated verification of systems comprising data, communication, and real-time aspects. We applied the tool chain to verify safety properties in an industrial case study from the European Train Control System (ETCS).
Characterizing the Impact of Substrate Noise on High-Speed Flash ADCs
Authors: Parastoo Nikaeen, Boris Murmann, Robert W. Dutton
Venue: Proceedings of the 9th international symposium on Quality Electronic Design (2008)

A 4-bit flash ADC is investigated in presence of substrate noise generated by switching activities in digital blocks. The impact of noise is analyzed in different building blocks of the ADC and is measured experimentally using a high-speed ADC test block fabricated in a 0.18-μm SiGe BiCMOS process. Measurement results show that noise spikes in the substrate cause distortion in the prototype ADC and degrade its SNDR by 2 dB (10%) at noise frequencies above 200 MHz.
A Blocking Scheme for Identification of Components and Sub-Components of Semi-Structured E-Documents
Authors: Azita A. Bahrami
Venue: Proceedings of the Fifth International Conference on Information Technology: New Generations (2008)

In order to convert a semi-structured e-document into an XML e-document, the physical components and sub-components of the e-document must be tagged. Such tagging is possible once the components and sub-components of the e-document are identified. A methodology, blocking scheme, is devised and used for this research effort to identify semi-structured e-documents’ components and sub-components. The methodology was applied on 50 semi-structured e-documents of a specific type and the identification of their components and sub-components were achieved with 100% accuracy.
Bridging the Gap between Legal and Technical Contracts
Authors: Alvaro Arenas, Michael Wilson, Shirley Crompton, Dana Cojocarasu, Tobias Mahler, Lutz Schubert
Venue: IEEE Internet Computing (2008)

Two or more parties typically establish a business relationship using a contract, but a large gap still exists between the provisions of contracts produced by lawyers and the details of computer security and performance addressed by technologists. Some contractual clauses address legal issues that technology can manage as well the TrustCoM framework offers a paradigm for automating these clauses as technical operations. If a business relationship forms across a service-oriented architecture, the parties involved often manage their collaboration as a virtual organization (VO). In TrustCoM, agreements are the key means of steering VO collaborations and mitigating the risks inherent in integrating processes and resources across organizational boundaries.
A case study in testing a network security algorithm
Authors: Carrie E. Gates
Venue: Proceedings of the 4th International Conference on Testbeds and research infrastructures for the development of networks & communities (2008)

Several difficulties arise when testing network security algorithms. First, using network data captured at a router does not guarantee that any instances of the security event of interest will be captured. Similarly, if the event of interest is not detected, this does not guarantee that it does not exist in the captured data. Further, such network data is often not publicly available, making comparisons with other detectors difficult. On the other extreme, purely simulated data can be made publicly available and can provide guarantees that the event of interest exists in the data set. However, simulated data often has unintended artifacts and may also incorporate the biases of the particular simulator. In this paper I describe an emulation approach that takes advantage of captured data while using the DETER network to generate realistic traffic for the event of interest. The problem domain was described in terms of seven variables, where the DETER network provided a flexible medium for examining the complete problem domain. The results of a set of experiments using this approach are provided, along with regression equations that describe the expected true and false positive rates.
Application of multistage stochastic programs solved in parallel in portfolio management
Authors: Maria Lucka, Igor Melichercik, Ladislav Halada
Venue: Parallel Computing (2008)

We present a multistage model for allocation of financial resources to bond indices in different currencies. The model was tested on historical data of interest and exchange rates. We compare a two-stage and a three-stage stochastic programming model from a financial performance point of view. For solving two-stage and three-stage stochastic programs the interior point method (IPM) in the frame of the primal-dual path following formulation is used. An application of the Birge and Qi factorization to the IPM allows decomposition of large linear system to smaller blocks allowing thus to solve it in parallel. The parallel code is written in the Fortran programming language, using the message passing interface (MPI) for communication. Parallel and financial performance is illustrated on experiments executed on the IBM 1350 Linux cluster.
Affective feedback: an investigation into the role of emotions in the information seeking process
Authors: Ioannis Arapakis, Joemon M. Jose, Philip D. Gray
Venue: Proceedings of the 31st annual international ACM SIGIR conference on Research and development in information retrieval (2008)

User feedback is considered to be a critical element in the information seeking process, especially in relation to relevance assessment. Current feedback techniques determine content relevance with respect to the cognitive and situational levels of interaction that occurs between the user and the retrieval system. However, apart from real-life problems and information objects, users interact with intentions, motivations and feelings, which can be seen as critical aspects of cognition and decision-making. The study presented in this paper serves as a starting point to the exploration of the role of emotions in the information seeking process. Results show that the latter not only interweave with different physiological, psychological and cognitive processes, but also form distinctive patterns, according to specific task, and according to specific user.
Lower bound on the profile of degree pairs in cross-intersecting set systems
Authors: Zsuzsanna Szaniszl&#x00f3;, Zsolt Tuza
Venue: Combinatorica (2007)

We raise the following problem. For natural numbers m, n &#x2265; 2, determine pairs d&#x2032;, d&#x2033; (both depending on m and n only) with the property that in every pair of set systems A, B with |A| &#x2264; m, |B| &#x2264; n, and A &#x2229; B &#x2260; 0 for all A &#x2208; A, B &#x2208; B, there exists an element contained in at least d&#x2032; |A| members of A and d&#x2033; |B| members of B. Generalizing a previous result of Kyureghyan, we prove that all the extremal pairs of (d&#x2032;, d&#x2033;) lie on or above the line (n &#x2212; 1) x + (m &#x2212; 1) y = 1. Constructions show that the pair (1 + &#x025b; / 2n &#x2212; 2, 1 + &#x025b; / 2m &#x2212; 2) is infeasible in general, for all m, n &#x2265; 2 and all &#x025b; > 0. Moreover, for m = 2, the pair (d&#x2032;, d&#x2033;) = (1 / n, 1 / 2) is feasible if and only if 2 &#x2264; n &#x2264; 4. The problem originates from Razborov and Vereshchagin&#x2019;s work on decision tree complexity.
What can history tell us?: towards different models of interaction with document histories
Authors: Adam Jatowt, Yukiko Kawai, Hiroaki Ohshima, Katsumi Tanaka
Venue: Proceedings of the nineteenth ACM conference on Hypertext and hypermedia (2008)

The current Web is a dynamic collection where little effort is made to version pages or to enable users to access historical data. As a consequence, they generally do not have sufficient temporal support when browsing the Web. However, we think that there are many benefits to be obtained from integrating documents with their histories. For example, a document's history can enable us to travel back through time to establish its trustworthiness. This paper discusses the possible types of interactions that users could have with document histories and it presents several examples of systems that we have implemented for utilizing this historical data. To support our view, we present the results of an online survey conducted with the objective of investigating user needs for temporal support on the Web. Although the results indicated quite low use of Web archives by users, they simultaneously emphasized their considerable interest in page histories.
RCCT: Robust Clustering with Cooperative Transmission for Energy Efficient Wireless Sensor Networks
Authors: Mahbod Ghelichi, Seied Kazem Jahanbakhsh, Esmaeil Sanaei
Venue: Proceedings of the Fifth International Conference on Information Technology: New Generations (2008)

Data gathering is a common but critical operation in many applications of wireless sensor networks. Innovative techniques that improve energy efficiency to prolong the network lifetime are highly required. Clustering is an effective topology control approach in wireless sensor networks, which can increase scalability and lifetime. These networks require robust wireless communication protocols that are energy efficient and provide low latency. In this paper, we develop and analyze an efficient cooperative transmission protocol with robust clustering (RCCT) for sensor networks that considers a fault-tolerant and energy-efficient distributed clustering with minimum overhead. RCCT distributes energy load by energy-aware member selection for cooperative data transmission. Simulation results show a better performance of RCCT as compared to the conventional protocols.
G3M: A Generalized Multimedia Data Model Based on MPEG-7
Authors: Qiong Zuo, Zhongsheng Cao
Venue: Proceedings of the 2008 International Conference on Multimedia and Ubiquitous Engineering (2008)

In this paper, a generalized multimedia database data model based on MPEG-7 named G3M is proposed and formally defined. Different from those XML Database Management System (DBMS) solutions for MPEG-7 storage and retrieval, G3M analyses the MPEG-7 Multimedia Description Schemes (MDS) throughout to construct user-preferred database schemas, and the prototype system is built on extensible Object-Relational DBMSs. With the strong expressiveness of MPEG-7, G3M represents various aspects of multimedia data well. Domain knowledge for special application demand can be defined and used as references in G3M.
Performance analysis challenges and framework for high-performance reconfigurable computing
Authors: Seth Koehler, John Curreri, Alan D. George
Venue: Parallel Computing (2008)

Reconfigurable computing (RC) applications employing both microprocessors and FPGAs have potential for large speedup when compared with traditional (software) parallel applications. However, this potential is marred by the additional complexity of these dual-paradigm systems, making it difficult to identify performance bottlenecks and achieve desired performance. Performance analysis concepts and tools are well researched and widely available for traditional parallel applications but are lacking in RC, despite being of great importance due to the applications' increased complexity. In this paper, we explore challenges and present new techniques in automated instrumentation, runtime measurement, and visualization of RC application behavior. We also present ideas for integration with conventional performance analysis tools to create a unified tool for RC applications as well as our initial framework for FPGA instrumentation and measurement. Results from a case study are provided using a prototype of this new tool.
Lattices, mobius functions and communications complexity
Authors: L. Lovasz
Venue: Proceedings of the 29th Annual Symposium on Foundations of Computer Science (1988)

A general framework for the study of a broad class of communication problems is developed. It is based on a recent analysis of the communication complexity of graph connectivity. The approach makes use of combinatorial lattice theory.