ppxscal/embedding_network huggingface dataset:
Comparative feasibility analysis of Wi-Fi in metropolitan and small municipalities: a system dynamics approach
Authors: Sang M. Lee, Gang-hoon Kim, Jongheon Kim
Venue: International Journal of Mobile Communications (2009)

Wireless broadband service has grown rapidly, with many local governments considering alternatives for providing such a service to their communities in order to make them more attractive to new businesses and tourists. The alternatives range from an unrestricted free market (with mixed service quality and coverage) to city- or community-sponsored service, which provides better control. The evaluation of such proposals is problematic due to the newness of the concept, which limits traditional cost-benefit analysis because of insufficient data. The system dynamics methodology is proposed for the analysis of Wi-Fi proposals in cities or local governments. The method is demonstrated with a comparison of the expected Wi-Fi performance for small and metropolitan locations, and an evaluation of safety (expected impact on crime), tourism (expected impact on visitors) and other economic benefits.
Use bootable Linux CD (BCCD) to teach cluster and parallel computing concepts: conference workshop
Authors: Baochuan Lu
Venue: Journal of Computing Sciences in Colleges (2009)

High performance computing education is needed at all levels of computer science education, but the need is especially clear in the undergraduate computer science curriculum. A Bootable Linux CD (BCCD) developed by Paul Gray from the University of Northern Iowa is available which provides a convenient way to boot a number of normal lab PCs into a real Linux cluster, through which students can experiment by managing it and running parallel programs on it. This BCCD approach is self-contained and non-invasive in that it provides all essential tools while keeping the original OS intact. The flexibility of this system allows the use of current pools of resources without the cost and pain of maintaining dedicated cluster resources, which is especially attractive to the computer science programs of small colleges.
Regularizing Flows over Lie Groups
Authors: Yaniv Gur, Nir Sochen
Venue: Journal of Mathematical Imaging and Vision (2009)

In this paper we discuss regularization of images that take their value in matrix Lie groups. We describe an image as a section in a principal bundle which is a fibre bundle where the fiber (the feature space) is a Lie group. Via the scalar product on the Lie algebra, we define a bi-invariant metric on the Lie-group manifold. Thus, the fiber becomes a Riemannian manifold with respect to this metric. The induced metric from the principal bundle to the image manifold is obtained by means of the bi-invariant metric. A functional over the space of sections, i.e., the image manifolds, is defined. The resulting equations of motion generate a flow which evolves the sections in the spatial-Lie-group manifold. We suggest two different approaches to treat this functional and the corresponding PDEs. In the first approach we derive a set of coupled PDEs for the local coordinates of the Lie-group manifold. In the second approach a coordinate-free framework is proposed where the PDE is defined directly with respect to the Lie-group elements. This is a parameterization-free method. The differences between these two methods are discussed. We exemplify this framework on the well-known orientation diffusion problem, namely, the unit-circle S 1 which is identified with the group of rotations in two dimensions, SO(2). Regularization of the group of rotations in 3D and 4D, SO(3) and SO(4), respectively, is demonstrated as well.
An integrated distributed processing approach for e-commerce system design and development
Authors: Sarandis Mitropoulos, Antonios Andreatos, Christos Douligeris
Venue: Proceedings of the 12th WSEAS international conference on Computers (2008)

This paper proposes an integrated approach for e-commerce business modeling and system design, based on the Reference Model of the Open Distributed Processing (RM/ODP) standard. Initially, the main concerns of e-commerce with respect to business modeling are presented; next, the requirements induced by this modeling and the generic e-commerce system interfaces are discussed. Then, the adoption of UML for describing ODP viewpoints as a flexible and efficient mean for designing e-commerce system functions is proposed. Finally, an integrated design methodology taking into account the mapping requirements between the ODP viewpoints is presented. Finally, future work and open issues are discussed.
Improving static resolution of dynamic class loading in Java using dynamically gathered environment information
Authors: Jason Sawin, Atanas Rountev
Venue: Automated Software Engineering (2009)

In Java software, one important flexibility mechanism is dynamic class loading. Unfortunately, the vast majority of static analyses for Java treat dynamic class loading either unsoundly or too conservatively. We present a novel semi-static approach for resolving dynamic class loading by combining static string analysis with dynamically gathered information about the execution environment. The insight behind the approach is that dynamic class loading often depends on characteristics of the environment that are encoded in various environment variables. Such variables are not static elements; however, their run-time values typically remain the same across multiple executions of the application. Thus, the string values reported by our technique are tailored to the current installation of the system under analysis. Additionally, we propose extensions of string analysis to increase the number of sites that can be resolved purely statically, and to track the names of environment variables. An experimental evaluation on the Java 1.4 standard libraries shows that a state-of-the-art purely static approach resolves only 28% of non-trivial sites, while our approach resolves 74% of such sites. We also demonstrate how the information gained from resolved dynamic class loading can be used to determine the classes that can potentially be instantiated through the use of reflection. Our extensions of string analysis greatly increase the number of resolvable reflective instantiation sites. This work is a step towards making static analysis tools better equipped to handle the dynamic features of Java.
Query ranking in probabilistic XML data
Authors: Lijun Chang, Jeffrey Xu Yu, Lu Qin
Venue: Proceedings of the 12th International Conference on Extending Database Technology: Advances in Database Technology (2009)

Twig queries have been extensively studied as a major fragment of XPATH queries to query XML data. In this paper, we study PXML-RANK query, (Q, k), which is to rank top-k probabilities of the answers of a twig query Q in probabilistic XML (PXML) data. A new research issue is how to compute top-k probabilities of answers of a twig query Q in PXML in the presence of containment (ancestor/descendant) relationships. In the presence of the ancestor/descendant relationships, the existing dynamic programming approaches to rank top-k probabilities over a set of tuples cannot be directly applied, because any node/edge in PXML may have impacts on the top-k probabilities of answers. We propose new algorithms to compute PXML-RANK queries efficiently and give conditions under which a PXML-RANK query can be processed efficiently without enumeration of all the possible worlds. We conduct extensive performance studies using both real and large benchmark datasets, and confirm the efficiency of our algorithms.
Injective coloring of planar graphs
Authors: Yuehua Bu, Dong Chen, André Raspaud, Weifan Wang
Venue: Discrete Applied Mathematics (2009)

A coloring of a graph G is injective if its restriction to the neighborhood of any vertex is injective. The injective chromatic number@g"i(G) of a graph G is the least k such that there is an injective k-coloring. In this paper we prove that if G is a planar graph with girth g and maximum degree @D, then (1) @g"i(G)=@D if either g>=20 and @D>=3, or g>=7 and @D>=71; (2) @g"i(G)@?@D+1 if g>=11; (3) @g"i(G)@?@D+2 if g>=8.
A Novel Receiver-Aided Scheme for Improving TCP Performance in Multihop Wireless Networks
Authors: Chen Chen, Hua Wang, Xin Wang, Min Li, Azman Osman Lim
Venue: Proceedings of the 2009 WRI International Conference on Communications and Mobile Computing - Volume 02 (2009)

In general, TCP sender will take all the packet losses as congestion caused and reduce the packet sending rate to avoid the worsening of network condition. In multihop wireless networks, the long propagation time, poor link quality and high bit error rate make this scheme slow-moving, overcompensated and inefficient.This paper proposes a new optimized data delivery scheme, called TCP receiver-aided (TCP-RA) scheme. By continuously observing the packet's end-to-end delay condition, the receiver can estimate the congestion degree and sense the changes of situation. When packet losses happen, the receiver will estimate the reason of loss and assist the sender to control sending rate more efficiently in congestion control. Compared with several contemporary TCP schemes, experimental studies reveal that the TCP-RA scheme can accurately differentiate various packet losses and efficiently improve the throughput performance by control the sending rate smartly.
Modeling of air traffic arrival operations through agent-based simulation
Authors: Sanjiv Shresta, Ralf H. Mayer
Venue: Proceedings of the 40th Conference on Winter Simulation (2008)

This paper reports on the development and validation of an agent based simulation model of air traffic control arrival operations. The simulation model includes modeling of both the structure and procedures of air traffic operations. It is thus suitable for evaluating the impacts of shifts in those structures and procedures. Three key operational metrics are introduced which are sensitive to the internal workings of air traffic arrival operations. The simulation model is validated by demonstrating agreement in those key metrics between the simulation and a set of baseline arrival operations radar data. After the simulation model has been shown to reproduce actual operations, select details of the simulation can be altered to incorporate proposed operational changes. The impact of the changes on the computer simulation will offer a prediction of how the operational changes will affect actual operations.
Design and conception of optical links simulator for telecommunication applications under Simulink environment
Authors: Ghezal Hadj Ahmed, Ouchar Ali
Venue: Proceedings of the 5th conference on Applied electromagnetics, wireless and optical communications (2007)

Optical fibers provide a medium in which microwave signals that modulate optical carriers can be transmitted and distributed with high bandwidth and very low losses. They are involved in many applications such as phased array antennas, CATV, radars and optical communications. In this work an optical link simulator is designed like a platform on which the transmission and optimization of systems could be carried out, this simulator will be developed under Simulink environment (A library will be developed). As case study we will simulate a complete 1,55 µm optical fiber link for the telecommunication applications, based essentially on laser diode modulated at 2,5 Gb/s, optical fiber with a given length and a photodiode with a given sensitivity.
A knowledge-based inference multicast protocol using adaptive fuzzy Petri nets
Authors: Tzu-Chiang Chiang, Cheng-Feng Tai, Ting-Wei Hou
Venue: Expert Systems with Applications: An International Journal (2009)

Multicast routing protocols need a new path discovery algorithm for a newly joining node (receiver) in an ad hoc network. One issue of the approach to find the nearest forwarding node for a new node is that it may increase the distance between the source node and the new members, which results in an increase in latency time and packet loss, as compared with the shortest path algorithms. This issue is important in a high collision network. In this paper, we propose a knowledge-based inference approach for a new path discovery for multicasting. A fuzzy Petri net agent, which is a special expert system, is introduced at each node to learn and to adjust itself to fit the dynamic conditions in a multicast ad hoc network. The simulation results show that the proposed approach is up to 67.17% more efficient in the packet delivery ratio as compared with a bandwidth effective multicast routing protocol.
Fatigue life assessment of a shell structure from different steel types: a case study using variable amplitude loadings
Authors: S. Abdullah, S. M. Beden, A. K. Ariffin, Z. M. Nopiah, A. Zaharim, M. M. Rahman
Venue: Proceedings of the 8th conference on Simulation, modelling and optimization (2008)

Based on fatigue failure theories (stress-life theories such as; Goodman and Gerber), this paper presents a technique to predict the fatigue life of a shell structure of different materials with application of measured variable amplitude loading. The finite element analysis technique was being used for the modelling and simulation. Numerical life prediction results of the shell materials, low and medium carbon steel (ASTM A533, AISI 1020, AISI 4340) are presented and discussed. There are many factors affecting the life predicted, a surface condition effect was shown here. Reasonable difference appears through the comparison of the above materials.
ILOG Elixir
Authors: Georg Sander
Venue: Graph Drawing: 16th International Symposium, GD 2008, Heraklion, Crete, Greece, September 21-24, 2008. Revised Papers (2009)

The Adobe technology platform including Adobe© Flexc© [2] and Adobe AIRTM [3] deliver portability, high performance and rich graphical UI to internet and desktop applications. ILOG Elixir [1] enhances this platform by adding advanced data visualization displays. It includes ready-to-use schedule displays, map displays, dials, gauges, 3D and radar charts, treemap charts and organization charts. ILOG Elixir is completely integrated with Adobe Flex Builder and fully supports Adobe Flexs data-binding and event models.
The emergent ICT culture of parliamentarians: The case of the Scottish Parliament
Authors: Colin Smith, C. William R. Webster
Venue: Information Polity (2008)

This article explores the ways in which information and communications technologies (ICTs) have become embedded within the activities of parliamentarians, by examining the experiences of Members of the Scottish Parliament (MSPs). The article presents an overview of exiting research in this area and suggests that many authors do not take into account the full range of functions and activities undertaken by a modern parliamentarian and consequently cannot fully perceive the extent to which these technologies support parliamentary life. Central to the article is a discussion of new unique longitudinal research data which provides empirical evidence of a significant technological orientation, and an emergent ICT culture, that is the outcome of the intertwined relationship between the adoption and use of new communications technologies by parliamentarians, and the established norms and procedures of parliamentary activity. The research findings presented here highlight the significant role played by new ICTs in the Scottish Parliament and the emerging new democratic system in Scotland. For the new Scottish Parliamentarians interacting with ICT is an important part of their daily life, to the extent that it would not be unreasonable to assert that use of these technologies has become a core parliamentary activity, possibly even to the extent that parliamentarians, and consequently the parliamentary system, have become reliant on the informational and communications capabilities embedded in ICTs. This is because these technologies are supporting a wide range of parliamentary roles and activities, and because they are underpinning a range of communicative relationships in the parliamentary arena and wider polity.
Minimally 3-restricted edge connected graphs
Authors: Qinghai Liu, Yanmei Hong, Zhao Zhang
Venue: Discrete Applied Mathematics (2009)

For a connected graph G=(V,E), an edge set S@?E is a 3-restricted edge cut if G-S is disconnected and every component of G-S has order at least three. The cardinality of a minimum 3-restricted edge cut of G is the 3-restricted edge connectivity of G, denoted by @l"3(G). A graph G is called minimally 3-restricted edge connected if @l"3(G-e)
Object Recognition in Presence of Blur from Fourier Transform Spectrum
Authors: Mausumi Pohit
Venue: Proceedings of the 2009 Seventh International Conference on Advances in Pattern Recognition (2009)

A new technique for recognition of objects in presence of blur is presented where the object features are chosen from the Fourier power spectrum on the locus of equal intensity points around the zero order spectrum. Here the property of 2D Fourier slice theorem and Fraunhofer distribution for 1D aperture is used to show that the spread of Fourier transform spectrum along any direction is related to the spread of the object along that direction. Computation is done on different intensity profiles to show the validity of the technique.
Approximated parameterized verification of infinite-state processes with global conditions
Authors: Parosh Aziz Abdulla, Giorgio Delzanno, Ahmed Rezine
Venue: Formal Methods in System Design (2009)

We present a simple and effective approximated backward reachability procedure for parameterized systems with existentially and universally quantified global conditions. The individual processes operate on unbounded local variables ranging over the natural numbers. In addition, processes may communicate via broadcast, rendez-vous and shared variables. The procedure operates on an over-approximation of the transition system induced by the parameterized system. We verify mutual exclusion for complex protocols such as atomic, non-atomic and distributed versions of Lamport's bakery algorithm.
Tactile Cloud Landscape
Authors: Kumiko Kushiyama
Venue: ACM SIGGRAPH ASIA 2008 artgallery: emerging technologies (2008)

This simulation of a natural landscape is a tactile artwork that interactively expresses images and movements of clouds. Images and tactile sensations incorporating the soft movements of clouds interact simultaneously to create a tactile display that reacts to human contact. This work could be used as a universal display for the disabled and for various other forms of global communications.
Multimedia and Security Demo at IEEE Multimedia Systems '99
Authors: Jana Dittmann
Venue: Proceedings of the 1999 IEEE International Conference on Multimedia Computing and Systems - Volume 02 (1999)

Recently security has become one of the most significant problems for spreading new information technology. Digital data can easily be copied and multiplied without information loss. This requires security solutions for such fields as distributed production processes and electronic commerce, since the producers seek to provide access control mechanisms to prevent misuse and theft of material. The demo presents security solutions for multimedia systems and multimedia material in the digital environment to ensure copyright protection and authentication of origin.
Composite finite elements for 3D image based computing
Authors: Florian Liehr, Tobias Preusser, Martin Rumpf, Stefan Sauter, Lars Ole Schwen
Venue: Computing and Visualization in Science (2009)

We present an algorithmical concept for modeling and simulation with partial differential equations (PDEs) in image based computing where the computational geometry is defined through previously segmented image data. Such problems occur in applications from biology and medicine where the underlying image data has been acquired through, e.g. computed tomography (CT), magnetic resonance imaging (MRI) or electron microscopy (EM). Based on a level-set description of the computational domain, our approach is capable of automatically providing suitable composite finite element functions that resolve the complicated shapes in the medical/biological data set. It is efficient in the sense that the traversal of the grid (and thus assembling matrices for finite element computations) inherits the efficiency of uniform grids away from complicated structures. The method&#x2019;s efficiency heavily depends on precomputed lookup tables in the vicinity of the domain boundary or interface. A suitable multigrid method is used for an efficient solution of the systems of equations resulting from the composite finite element discretization. The paper focuses on both algorithmical and implementational details. Scalar and vector valued model problems as well as real applications underline the usability of our approach.
On Performance of Clustering-Based Limited Feedback Beamforming in Multiple-Antenna OFDM Systems
Authors: Erlin Zeng, Shihua Zhu, Xuewen Liao, Zhimeng Zhong, Zhenjie Feng
Venue: IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences (2008)

Prior studies on limited feedback (LFB) beamforming in multiple-antenna orthogonal frequency division multiplexing (OFDM) have resorted to Monte-Carlo simulations to evaluate the system performance. This letter proposes a novel analytical framework, based on which the averaged signal-to-noise ratio and the ergodic capacity performance of clustering-based LFB beamforming in multiple-antenna OFDM systems are studied. Simulations are also provided to verify the analysis.
A Parallel Branching Program Machine for Emulation of Sequential Circuits
Authors: Hiroki Nakahara, Tsutomu Sasao, Munehiro Matsuura, Yoshifumi Kawamura
Venue: Proceedings of the 5th International Workshop on Reconfigurable Computing: Architectures, Tools and Applications (2009)

The parallel branching program machine (PBM128) consists of 128 branching program machines (BMs) and a programmable interconnection. To represent logic functions on BMs, we use quaternary decision diagrams. To evaluate functions, we use 3-address quaternary branch instructions. We emulated many benchmark circuits on PBM128, and compared its memory size and computation time with the Intel's Core2Duo microprocessor. PBM128 requires approximately quarter of the memory for the Core2Duo, and is 21.4-96.1 times faster than the Core2Duo.
Structured system design for blended technology in classroom
Authors: Hanafizan Hussain
Venue: Proceedings of the 12th WSEAS international conference on Computers (2008)

Course planning in universities involves balancing multiple objectives. Through years of experiences in face-to-face teaching, faculty members have generated a great deal of knowledge and skill, which is often categorized by automatic routines and tacit knowledge. The advent of web and the growing of multimedia technology in education industry are transforming the context. This paper proposed a structured design for blended technology in classroom which comprehensively represents the scenario pf face-to-face and delivery methods in higher education. It requires the use of new tools as well as the creation and transformation of artifacts. It also poses new problems that require new kinds of support and collaboration since the faculty members may lack the technical ability to create their own blended course classes.