ppxscal/embedding_network huggingface dataset:
On several graph related algorithms and protocols in wireless security
Authors: Kenneth W. Regan
Venue:  (2008)

This dissertation studies graph-theoretic problems related to security protocols in wireless networks. Many current wireless protocols lack necessary security and reliability measure due to the properties of wireless networks. In many cases, we can model a wireless network as a graph, and many security problems are related to problems in graph theory. In our research, we mainly focus on the following issues: (1) Minimum cost blocking in wireless mesh networks. In wireless mesh networks, outgoing data traffic usually goes out from a node inside the network to a number of gateways. The advantage of sending traffic to different gateways is that it can improve both reliability and security. Especially for some threshold security protocols, for a specific node, if the number of correctly received data packets heading for different destinations are more than a certain threshold, then the protocols can be executed correctly. If an adversary can block a certain number of paths related to a node, then the number of correctly received data packets originating from the node may be smaller than the threshold, and the adversary achieves his/her goal. We demonstrate the general version of minimum cost blocking problem, show its hardness and designed several approximation algorithms for it. (2) Report dropping and tampering detection in sensor networks. Achieving communication dependability in sensor networks is difficult due to limitations on node power and wireless channel unreliability. We use a new measure of node disjointedness to find proxy route to improve security and reliability, we also show that to find an optimal proxy route is NP-hard, and give a detailed analysis of the proxy route based schemes. (3) Time difference related problems. Time difference related problems originate from group time synchronization protocols in wireless sensor networks. In these protocols, every group member needs to synchronize their clock since there will be some time difference after they are deployed. In many cases, the group time synchronization protocol is executed in a cluster where a node can compute the time difference between itself and its neighboring nodes. We introduce the Maximum Consistent Time Difference (MCTD) subgraph problem and the Minimum Time Difference Adjustment (MTDA) problem, analyze their hardness, and propose some algorithms for MCTD. (4) Key update protocol related problems. We generalize the ideas and principles of the hierarchical key structure, and analyze several graph related problems in key update protocols.
An Asynchronous Parallelized and Scalable Image Resampling Algorithm with Parallel I/O
Authors: Yan Ma, Lingjun Zhao, Dingsheng Liu
Venue: Proceedings of the 9th International Conference on Computational Science (2009)

Image resampling which is frequently used in remote sensing processing procedure is a time-consuming task. Parallel computing is an effective way to speed up. However, recent parallel image resampling algorithms with massive time-consuming global processes like I/O, always lead to low efficiency and non-linear speedup ratio, especially when the amount of computing nodes increases to a certain extent. And what's more, the various geo-referencing related to different processing applications caused a real problem of code reuse. To solve these problems, Parallel Image Resampling Algorithm with Parallel I/O (PIRA-PIO) which is an asynchronous parallelized image resampling algorithm with parallel I/O is proposed in this paper. Parallel I/O of parallel file system and asynchronous parallelization which using I/O hidden policy to sufficiently overlap the computing time with I/O time are used in PIRA-PIO for performance enhancement. In addition, the design of reusable code like design pattern will be used for the improving of flexibility in different remote sensing image processing applications. Through experimental and comparative analysis, its outstanding parallel efficiency and perfect linear speedup is showed in this paper.
Encyclopedia of GIS, 1st edition
Authors: Shashi Shekhar, Hui Xiong
Venue:  (2007)

The Encyclopedia of GIS features an alphabetically arranged comprehensive and authoritative treatment of this subject matter. Authored by world experts and peer-reviewed for accuracy and currency, the entries explain the key software, data sets, and processes used by geographers and computational scientists. Nearly 200 topics include major overviews, such as Geoinformatics, Spatial Cognition, and Location-Based Services. Short entries define specific terms and concepts, such as the Global Positioning System, Digital Elevation/Terrain Model, and Remote Sensing. Larger entries include key citations to the literature, and (online) internal hyperlinks to definitional entries and current standards. The reference will be published as a print volume with abundant black and white art, and simultaneously as an XML online reference with hyperlinked citations, cross-references, four-color art, links to web-based maps, and other interactive features.
2017: The End of IT as We Know It, 1st edition
Venue:  (2007)

It s this simple: people, processes, and technology are the three basic elements that make up any company, and how they work together defines how successful a company is or can be. For far too long, these elements haven't worked together as effectively as they should. Oftentimes, they're at odds. But today's globally integrated world demands more, particularly of IT. Over the next 10 years, the office of the CIO will play an increasingly vital role in carrying out the objectives of the business. As we head toward 2017, the lines between technology and the business it supports continue to blur. In 2017, the applications will be the business processes, and companies need to start preparing now for the future. 2017: The End of IT as We Know It examines the current state of IT, where it's heading, and what it needs to do to get there. This is the definitive guide for helping today's company become the performance-driven leader of tomorrow. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
A practical new approach to 3D scene recovery
Authors: Qingbo Zhu, Hongyuan Wang, Wen Tian
Venue: Signal Processing (2009)

An efficient new approach to 3D scene reconstruction from an uncalibrated image sequence without anything known about the scene and the cameras is proposed. Present algorithms cannot deal with cameras with aspect ratio deviated from 1.0 well. Camera intrinsic parameters are skillfully handled in the cost function of the self-calibration phase to dispose the variable aspect ratio. Compared with existing algorithms, both intrinsic parameters of cameras and feature points of the scene, can be recovered efficiently, even for the cameras with aspect ratio greatly deviated from 1.0, like 0.6 and 2.3 in practice. Both synthetic and real data have been used to test the proposed method. The method is verified to be more accurate and practical than state-of-the-art algorithms, even if the aspect ratio is 2.5. Moreover, the reconstruction does not require any further non-linear optimization for general applications.
2LIP: filling the gap between the current and the three-dimensional web
Authors: Jacek Jankowski, Stefan Decker
Venue: Proceedings of the 14th International Conference on 3D Web Technology (2009)

In this article we present a novel approach, the 2-Layer Interface Paradigm (2LIP), for designing simple yet interactive 3D web applications, an attempt to marry advantages of 3D experience with the advantages of the narrative structure of hypertext. The hypertext information, together with graphics, and multimedia, is presented semi-transparently on the foreground layer. It overlays the 3D representation of the information displayed in the background of the interface. Hyperlinks are used for navigation in the 3D scenes (in both layers). We introduce a reference implementation of 2LIP: Copernicus - The Virtual 3D Encyclopedia, which can become a model for building 3D Wikipedia. Based on the evaluation of Copernicus we show that designing web interfaces according to 2LIP provides users with a better experience during browsing the Web, has a positive effect on the visual and associative memory, improves spatial cognition of presented information, and increases overall user's satisfaction without harming the interaction.
Cata-Fisheye Camera for Panoramic Imaging
Authors: Gurunandan Krishnan, Shree K. Nayar
Venue: Proceedings of the 2008 IEEE Workshop on Applications of Computer Vision (2008)

We present a novel panoramic imaging system which uses a curved mirror as a simple optical attachment to a fish-eye lens. When compared to existing panoramic cameras, our "cata-fisheye" camera has a simple, compact and inexpensive design, and yet yields high optical performance. It captures the desired panoramic field of view in two parts. The upper part is obtained directly by the fisheye lens and the lower part after reflection by the curved mirror. These two parts of the field of view have a small overlap that is used to stitch them into a single seamless panorama. The cata-fisheye concept allows us to design cameras with a wide range of fields of view by simply varying the parameters and position of the curved mirror. We provide an automatic method for the one-time calibration needed to stitch the two parts of the panoramic field of view. We have done a complete performance evaluation of our concept with respect to (i) the optical quality of the captured images, (ii) the working range of the camera over which the parallax is negligible, and (iii) the spatial resolution of the computed panorama. Finally, we have built a prototype cata-fisheye video camera with a spherical mirror that can capture high resolution panoramic images (3600x550 pixels) with a 360° (horizontal) x 55° (vertical) field of view.
Testing inertial sensor performance as hands-free human-computer interface
Authors: Josip Music, Mojmil Cecic, Mirjana Bonkovic
Venue: WSEAS Transactions on Computers (2009)

The paper introduces hands-free human-computer interface designed around commercially available inertial sensor pack. It is primarily intended to provide computer access for people with little or no upper-limb functionality, but can be used by able bodied subject in certain application scenarios. The performance of the proposed device was evaluated on twelve healthy subjects performing multi-directional point-and-select task with throughput as the main performance parameter. The system was tested using two different pointer control schemes, as well as three selection techniques. Test subjects were given two questionnaires (one per control scheme) in order to provide comfort assessment of the device and short post-measurement interviews with test subjects provided user feedback. Obtained performance and comfort assessment results are presented and discussed.
Nonlinear time series modeling using spline-based nonparametric models
Authors: Jun M. Liu
Venue: Proceedings of the 15th american conference on Applied mathematics (2009)

In this paper we use the polynomial splines-based nonparametric transfer function method to study how river flow is affected by multiple factors. The highly nonlinear relationship between river flow and the independent variables (the transfer function) is modeled using polynomial spline, and the noise term assumed to follow a parametric Autoregressive (AR) model. The transfer function is modeled jointly with the AR parameters. Because of its flexibility, spline functions are ideal for modeling highly nonlinear relationships with unknown functional forms; by modeling the noise explicitly, the correlation in the data is removed so the transfer function can be estimated more efficiently. Additionally, the estimated AR parameters can be used to improve the forecasting performance. The proposed polynomial splines-based estimator is also highly computationally efficient. A comparison of the results show that the performance of this model is better than some widely accepted benchmark models.
CUDA Solutions for the SSSP Problem
Authors: Pedro J. Martín, Roberto Torres, Antonio Gavilanes
Venue: Proceedings of the 9th International Conference on Computational Science: Part I (2009)

We present several algorithms that solve the single-source shortest-path problem using CUDA. We have run them on a database, composed of hundreds of large graphs represented by adjacency lists and adjacency matrices, achieving high speedups regarding a CPU implementation based on Fibonacci heaps. Concerning correctness, we outline why our solutions work, and show that a previous approach [10] is incorrect.
Run-time correlation engine for system monitoring and testing
Authors: Viliam Holub, Trevor Parsons, Patrick O'Sullivan, John Murphy
Venue: Proceedings of the 6th international conference industry session on Autonomic computing and communications industry session (2009)

Today's enterprise applications can produce vast amounts of information both during system testing and in production. Correlation of this information can be difficult as it is generally stored in a range of different event logs, the format of which can be application or vendor specific. Furthermore these large logs can be physically distributed across a number of different locations. As a result it can be difficult to form a coherent understanding of the overall system behaviour. This has implications for a number of domains (e.g. autonomic computing, system testers), where an understanding of the system behaviour at run-time is required (e.g. for problem determination, autonomic management etc.) This paper presents an approach and implementation of run-time correlation of large volumes of log data and symptom matching of known issues in the context of large enterprise applications. Our solution provides for automatic data collection, data normalisation into a common format, run-time correlation and analysis of the data to give a coherent view of system behaviour at run-time and a symptom matching mechanism that can identify known errors in the correlated data on the fly.
Review: Ambient intelligence: Technologies, applications, and opportunities
Authors: Diane J. Cook, Juan C. Augusto, Vikramaditya R. Jakkula
Venue: Pervasive and Mobile Computing (2009)

Ambient intelligence is an emerging discipline that brings intelligence to our everyday environments and makes those environments sensitive to us. Ambient intelligence (AmI) research builds upon advances in sensors and sensor networks, pervasive computing, and artificial intelligence. Because these contributing fields have experienced tremendous growth in the last few years, AmI research has strengthened and expanded. Because AmI research is maturing, the resulting technologies promise to revolutionarize daily human life by making people's surroundings flexible and adaptive. In this paper, we provide a survey of the technologies that comprise ambient intelligence and of the applications that are dramatically affected by it. In particular, we specifically focus on the research that makes AmI technologies ''intelligent''. We also highlight challenges and opportunities that AmI researchers will face in the coming years.
Possibilities for increasing the use of machineries using computer assisted statistical methods
Authors: Ilie Mitran, Florin Dumitru Popescu, Marin Silviu Nan, Septimiu Sorin Soba
Venue: WSEAS Transactions on Mathematics (2009)

Reliability has recently emerged from the quality concept. If quality represents the total of a product's qualities, which make it good for use according to the destination, the reliability represents the capacity of the product to maintain its quality during the entire usage time. Reliability is the quality of the product extended through time. Reliability, maintenance, availability and capacity related aspects have been treated distinctively up to one moment. Analytically, the reliability represents the probability that during a given period of time, a product will be flawless. The technological capability or reliability represents way in which a technological system may realize, on the entire process of fulfilling a mission, the corresponding technological performances for its objectives. A unitary approach, considering all the factors, in accordance to the operating conditions of technical systems, lays the fundaments of an interdisciplinary theory, called the Theory of safety during operation. The safety during operation, S, of a machinery or of a technological system represents the way it will fulfill its mission, being a function of availability A, reliability R, capacity C and maintenance M: S(t) = r[A(t);R(t);C(t);M(T)].
Diversity Maintenance Strategy Based on Global Crowding
Authors: Qiong Chen, Shengwu Xiong, Hongbing Liu
Venue: Proceedings of the 6th International Symposium on Neural Networks: Advances in Neural Networks - Part III (2009)

In the design of multi-objective evolutionary algorithm, the diversity maintenance is essential to access the convergence of multi-objective optimization solutions. This paper presents a new diversity maintenance strategy based on global crowding, which is addressed for pruning non-dominated solutions as well as preserving a wide-spread distributed solution set and maintaining population diversity. Later on, inspired by the conception of entropy in information theory, the entropy metrics is defined and applied to assess the proposed strategy. Two-dimensional and multi-dimensional numerical experiment results demonstrate that the proposed strategy shows better performance in the entropy reduction and losses of uniform distribution than traditional diversity maintenance strategies.
A Decomposition Technique for Max-CSP
Authors: Hachémi Bennaceur, Christophe Lecoutre, Olivier Roussel
Venue: Proceeding of the 2008 conference on ECAI 2008: 18th European Conference on Artificial Intelligence (2008)

The objective of the Maximal Constraint Satisfaction Problem (Max-CSP) is to find an instantiation which minimizes the number of constraint violations in a constraint network. In this paper, inspired from the concept of inferred disjunctive constraints introduced by Freuder and Hubbe, we show that it is possible to exploit the arc-inconsistency counts, associated with each value of a network, in order to avoid exploring useless portions of the search space. The principle is to reason from the distance between the two best values in the domain of a variable, according to such counts. From this reasoning, we can build a decomposition technique which can be used throughout search in order to decompose the current problem into easier sub-problems. Interestingly, this approach does not depend on the structure of the constraint graph, as it is usually proposed. Alternatively, we can dynamically post hard constraints that can be used locally to prune the search space. The practical interest of our approach is illustrated, using this alternative, with an experimentation based on a classical branch and bound algorithm, namely PFC-MRDAC.
Plenary lecture 5: new trends in access control for information systems
Authors: Tugkan Tuglular
Venue: Proceedings of the 8th Wseas international conference on Telecommunications and informatics (2009)

The concept of access control relates to permissions and obligations, which are represented by rules in different granularities, and their enforcement achieved by various operating systems, network software/hardware, and applications. Involvement of different technologies, vendors, and standards make it hard to provide a complete solution in access control for information systems. Moreover, access control requirements started to change with the increased development and use of large-scale, distributed, loosely coupled applications, which run on open and complex environments. This talk will reveal long-time existing access control approaches, declare new requirements for access control and present new trends in the access control field.
Empirical Evaluation of Graph Partitioning Using Spectral Embeddings and Flow
Authors: Kevin J. Lang, Michael W. Mahoney, Lorenzo Orecchia
Venue: Proceedings of the 8th International Symposium on Experimental Algorithms (2009)

We present initial results from the first empirical evaluation of a graph partitioning algorithm inspired by the Arora-Rao-Vazirani algorithm of [5], which combines spectral and flow methods in a novel way. We have studied the parameter space of this new algorithm, e.g., examining the extent to which different parameter settings interpolate between a more spectral and a more flow-based approach, and we have compared results of this algorithm to results from previously known and optimized algorithms such as Metis.
An approach for evaluating User Model Data in an interoperability scenario
Authors: Francesca Carmagnola, Federica Cena
Venue: Proceeding of the 2006 conference on STAIRS 2006: Proceedings of the Third Starting AI Researchers' Symposium (2006)

A common vision, in user-adapted community, states that user model should be interoperable and shareable across applications in different contexts and environments. The core idea of our approach is that the interoperability of user model data lets to reach more effective adaptation results only if the exchanged data are reliable. In this paper we illustrate how the usage of Semantic Web techniques can support evaluation of data reliability, and thus improves this sharing.
Ionospheric effects on GPS range finding using 3D ray-tracing and Nelder-Mead optimisation algorithm
Authors: Siti Sarah Nik Zulkifli, Mardina Abdullah, Azami Zaharim, Mahamod Ismail
Venue: WSEAS Transactions on Mathematics (2009)

The Earth's ionosphere plays a crucial role in Global Positioning System (GPS) accuracy because his layer represents the largest source of positioning error for the users of the GPS after the turn-off of Selective Availability (SA). This paper studies the ionospheric effect on transionospheric signal propagation for the Earth-satellite path using 3D Jones Ray-Tracing utilizing Nelder-Mead optimisation algorithm. The ionospheric delay or advance is obtained from the difference between the distance of the ray path from the satellite to the receiver determined from the ray-tracing and the distance for propagation over the line of sight (LOS) at the velocity of light in vacuum. The difference between the standard dual-frequency models corrected range and LOS, known as Residual Range Error (RRE) is calculated. Results show that the RRE of group delay value is different from RRE of phase advance. On the other hand, the group and phase path is longer when considering the geomagnetic field effect on both GPS frequencies L1 and L2. The higher order term in total electron content (TEC) calculation that relates to the refractive index is normally neglected due to its small value, but it is clearly shown that it does have some effects in ray-tracing. This analysis needs to be considered for more accurate GPS range finding.
Bounded model checking of CTL
Authors: Zhi-Hong Tao, Cong-Hua Zhou, Zhong Chen, Li-Fu Wang
Venue: Journal of Computer Science and Technology (2007)

Bounded Model Checking has been recently introduced as an efficient verification method for reactive systems. This technique reduces model checking of linear temporal logic to propositional satisfiability. In this paper we first present how quantified Boolean decision procedures can replace BDDs. We introduce a bounded model checking procedure for temporal logic CTL* which reduces model checking to the satisfiability of quantified Boolean formulas. Our new technique avoids the space blow up of BDDs, and extends the concept of bounded model checking.