ppxscal/embedding_network huggingface dataset:
Good reduction of puiseux series and complexity of the Newton-Puiseux algorithm over finite fields
Authors: Adrien Poteaux, Marc Rybowicz
Venue: Proceedings of the twenty-first international symposium on Symbolic and algebraic computation (2008)

In [12], we sketched a numeric-symbolic method to compute Puiseux series with floating point coefficients. In this paper, we address the symbolic part of our algorithm. We study the reduction of Puiseux series coefficients modulo a prime ideal and prove a good reduction criterion sufficient to preserve the required information, namely Newton polygon trees. We introduce a convenient modification of Newton polygons that greatly simplifies proofs and statements of our results. Finally, we improve complexity bounds for Puiseux series calculations over finite fields, and estimate the bit-complexity of polygon tree computation.
Structure of a sampling rate converter based on elementary signal processing blocks
Authors: Eduardo Martos-Naya, Jesús López-Fernández, Luis Díez del Río, José Tomás Entrambasaguas Muòoz
Venue: Digital Signal Processing (2008)

Sampling rate conversion is a technique widely used in many areas. For the most general case of an irrational and time varying conversion factor, a discrete time varying filter is needed together with a sample skip and/or sample duplicate operation. The functionality of this skip/duplicate block has not been treated in proper depth in the bibliography and in many cases it has been ambiguously described and located in the structure of a sampling rate converter. In this paper a detailed analysis of a sampling rate converter for an arbitrary and variable ratio is revisited. The operations involved to carry out the conversion and the order in which they must be performed lead to a novel structure where only elementary signal processing blocks (adders, multipliers, delays, and decimators) are employed to describe both the filtering and the skip/duplicate operations. This structure constitutes an improvement in clarity with respect to previous works.
Complexity of unification in free groups and free semi-groups
Authors: A. Koscielski
Venue: Proceedings of the 31st Annual Symposium on Foundations of Computer Science (1990)

It is proved that the exponent of periodicity of a minimal solution of a word equation is at most 2/sup 2.54n/, where n is the length of the equation. Since the best known lower bound is 2/sup 0.31n/, this upper bound is almost optimal and exponentially better than the original bound. Thus the result implies exponential improvement of known upper bounds on complexity of word-unification algorithms. Evidence is given that, contrary to common belief, the algorithm deciding satisfiability of equations in free groups, given by G.S. Makanin (1977), is not primitive recursive.
Minimization of the root of a quadratic functional under a system of affine equality constraints with application to portfolio management
Authors: Zinoviy Landsman
Venue: Journal of Computational and Applied Mathematics (2008)

We present an explicit closed form solution of the problem of minimizing the root of a quadratic functional subject to a system of affine constraints. The result generalizes Z. Landsman, Minimization of the root of a quadratic functional under an affine equality constraint, J. Comput. Appl. Math. 2007, to appear, see , articles in press, where the optimization problem was solved under only one linear constraint. This is of interest for solving significant problems pertaining to financial economics as well as some classes of feasibility and optimization problems which frequently occur in tomography and other fields. The results are illustrated in the problem of optimal portfolio selection and the particular case when the expected return of finance portfolio is certain is discussed.
Some competition programming problems as the beginning of artificial intelligence
Authors: Boris Melnikov, Elena Melnikova
Venue: Informatics in education (2007)

We consider in this paper some programming competition problems (which are near to some problems of ACM competitions) of the following subjects: we can make their solution using both Prolog and a classical procedure-oriented language. Moreover, the considered problems are selected that their solution in Prolog and in a classical procedure-oriented language are similar - i.e., in other words, they use the same working mechanism, the same approach to constructing recursive functions etc. However, the main goal of this paper is to demonstrate, that the solution of most of these problems by the students is a step to design the real problems of artificial intellegence.
Asymptotically fast algorithms for spherical and related transforms
Authors: J. R. Driscoll, D. M. Healy
Venue: Proceedings of the 30th Annual Symposium on Foundations of Computer Science (1989)

The problem of computing the convolution of two functions on the sphere by means of a spherical transform is considered. Such convolutions are applicable to surface recognition and the location of both rotated and translated patterns in an image. The authors give convolution theorems that relate the spherical transform to convolution, sampling theorems that allow the exact computation of the transform for band-limited functions, and algorithms with asymptotically improved running time for the exact computation of the harmonic expansion. The net result is an O(n/sup 1.5/(log n)/sup 2/) algorithm for the exact computation of the convolution of two bandlimited functions sampled at n points in accordance with the sampling theorem. The techniques developed are applicable to computing other transforms, such as the Laguerre, Hermite, and Hankel transforms.
Algorithm for stereovision disparity calculation in the moment space
Authors: Tomasz Andrysiak, Michał Choras
Venue: Machine Graphics Vision International Journal (2006)

This article presents various theoretical and experimental approaches to the problem of stereo matching and disparity estimation. We propose to calculate stereo disparity in the moment space, but we also present numerical and correlation-based methods. In order to calculate the disparity vector, we decided to use the discrete orthogonal moments of Tchebichef, Zernike and Legendre. In our research in stereo disparity estimation, all of those moments were tested and compared. Experimental results confirm effectiveness of the presented methods for determining stereo disparity and stereo matching for robotics and machine vision applications.
Extracting structural characteristics of herbaceous floodplain vegetation under leaf-off conditions using airborne laser scanner data
Authors: M. Straatsma, H. Middelkoop
Venue: International Journal of Remote Sensing (2007)

Hydrodynamic models of river flow need detailed and accurate friction values as input. Friction values of floodplain vegetation are based on vegetation height and density. To map spatial patterns of floodplain vegetation structure, airborne laser scanning is a promising tool. In a test for the lower Rhine floodplain, vegetation height and density of herbaceous vegetation were measured in the field at 42 georeferenced plots of 200 m2 each. Simultaneously, three airborne laser scanning (ALS) surveys were carried out in the same area resulting in three high resolution, first pulse, small-footprint datasets. The laser data surveys differed in flying height, gain setting and laser diode age. Point density of the laser data varied between 10 and 75 points m-2. Point heights relative to the DTM derived from the ALS data were used in all analyses. Laser points were labelled as either vegetation or ground using three different methods: (1) a fixed threshold value; (2) a flexible threshold value based on the inflection point in the point height distribution; and (3) using a Gaussian distribution to separate noise in the ground surface points from vegetation. Twenty-one statistics were computed for each of the resulting vegetation-point distributions, which were subsequently compared with field observations of vegetation height. Additionally, the percentage index (PI) was computed to relate density of vegetation points to hydrodynamic vegetation density. The vegetation height was best predicted by using the inflection method for labelling and the 95 percentile as a regressor (R 2 = 0.74-0.88). Vegetation density was best predicted using the threshold method for labelling and the PI as a predictor (R 2 = 0.51). The results of vegetation height prediction were found to depend on the combined effect of flying height, gain setting or laser diode age. The quality of the estimation of vegetation height and density is also affected by point density, for densities lower than 15 points m-2. We conclude that high resolution ALS data allows to estimate vegetation height and density of herbaceous vegetation in winter condition, but field reference data remains necessary for calibration.
Energy Effective Geographical Routing Considering Wireless Link Condition in WSN
Authors: Inbo Sim, Jaiyong Lee
Venue: Proceedings of the 2008 International Conference on Multimedia and Ubiquitous Engineering (2008)

Greedy packet forwarding used in geographical routing protocols is an attractive localized routing scheme for wireless sensor networks because of its directional routing property and scalability. However, pure greedy routing does not take account of wireless link condition. This brings out the retransmissions because of received packet’s errors. Also, because of these retransmissions, additional power is consumed. In this paper, wireless link condition being considered, we determine the distance dop with which reliable data transmission is made and the consumed energy is minimized, using the geographical routing protocol. Based on the greedy packet forwarding with this distance, energy effective geographical routing considering wireless link condition can be done.
A Scheme for Damage Information Gathering Based on Micro Perspective in Sensor Networks
Authors: Takahiro Fujiwara, Takashi Watanabe
Venue: Proceedings of the 22nd International Conference on Advanced Information Networking and Applications - Workshops (2008)

Several systems for disaster damage mitigation have been studied based on various perspectives. Those previous works suggest it is not easy to get an effective method to comprehend damage conditions due to diversity of disaster damage. This paper discusses a scheme for damage assessment information gathering based on macro and micro perspectives. We, especially, take notice of sensor networks, which play a significant role for the micro perspective. Discussion of this paper for damage monitoring is still open-ended, since unexpected circumstances may lurk in a disaster, and technical environments useful for disaster will even more progress. Moreover, integration of the macro and micro perspectives for damage information gathering should be a significant future work.
TRAILS, a Toolkit for Efficient, Realistic and Evolving Models of Mobility, Faults and Obstacles in Wireless Networks
Authors: Ioannis Chatzigiannakis, Athanasios Kinalis, Georgios Mylonas, Sotiris Nikoletseas, Grigoris Prasinos, Christos Zaroliagis
Venue: Proceedings of the 41st Annual Simulation Symposium (anss-41 2008) (2008)

We present a new simulation toolkit called TRAILS (Toolkit for Realism and Adaptivity In Large-scale Simulations), which extends the ns-2 simulator by adding important functionality and optimizing certain critical simulator operations. The added features provide the tools to study wireless networks of high dynamics. TRAILS facilitates the implementation of advanced mobility patterns, obstacle presence and disaster scenarios, and failures injection that can dynamically change throughout the execution of the simulation. Moreover, we define a set of utilities that enhance the use of ns-2. This functionality is implemented in a simple and flexible architecture, that follows design patterns, object oriented and generic programming principles, maintaining a proper balance between reusability, extendability and ease of use. We evaluate the performance of TRAILS and show that it offers significant speed-ups regarding the execution time of ns-2 in certain important, common wireless settings. Our results also show that this is achieved with minimum overhead in terms of memory usage.
From the Archives: Reading Stimson's Mail
Authors: Craig Bauer, Joel Burkholder
Venue: Cryptologia (2007)

Henry L. Stimson is best known to readers of this journal for his quote, "Gentlemen do not read each other's mail," and his shutting down of Herbert O. Yardley's black chamber. The present piece reveals a second cryptologic episode from his life. During WWII, Stimson made a request of hundreds of libraries that they withdraw all material on explosives, secret inks, and ciphers from circulation and report the names of anyone requesting these materials to the local office of the Federal Bureau of Investigation (FBI). A pair of original documents is reproduced for the first time along with some references. A list of libraries contacted is also provided.
Real root isolation for exp-log functions
Authors: Adam Strzebonski
Venue: Proceedings of the twenty-first international symposium on Symbolic and algebraic computation (2008)

We present a real root isolation procedure for univariate functions obtained by composition and rational operations from exp, log, and real constants. We discuss implementation of the procedure and give empirical results. The procedure requires the ability to determine signs of exp-log functions at simple roots of other exp-log functions. The currently known method to do this depends on Schanuel's conjecture [6].
A stabilized stochastic finite element second-order projection method for modeling natural convection in random porous media
Authors: Xiang Ma, Nicholas Zabaras
Venue: Journal of Computational Physics (2008)

We consider natural convection in flow saturated porous media with random porosity. The porosity is treated as a random field and a stochastic finite element method is developed. The stochastic projection method is considered for the solution of the high-dimensional stochastic Navier-Stokes equations since it leads to the uncoupling of the velocity and pressure degrees of freedom. Because of the porosity dependence of the pressure gradient term in the governing flow equations, one cannot use the first-order projection method. A stabilized stochastic finite element second-order projection method is presented based on a pressure gradient projection. A two-dimensional stochastic problem with moderate and large variation in the random porosity field is examined and the results are compared with Monte-Carlo and sparse grid (Smolyak) collocation approaches. Excellent agreement between these results indicates the effectiveness and accuracy of the proposed methodology.
Towards a fast and reliable software implementation of SLI-FLP hybrid computer arithmetic
Authors: Xunyang Shen, Peter R. Turner
Venue: Proceedings of the 6th WSEAS International Conference on Systems Theory & Scientific Computation (2006)

In this paper we describe a C++ implementation of a hybrid system combining SLI (symmetric level-index) arithmetic and FLP (floating-point) arithmetic. The principal motivation for the work to be presented is to promote the use of SLI arithmetic as a practical framework for scientific computing. This hybrid arithmetic is essentially overflow and underflow free, and its implementation has shown the suitability to be used in real life computations.
Control theory-based DVS for interactive 3D games
Authors: Yan Gu, Samarjit Chakraborty
Venue: Proceedings of the 45th annual Design Automation Conference (2008)

We propose a control theory-based dynamic voltage scaling (DVS) algorithm for interactive 3D game applications running on battery-powered portable devices. Using this scheme, we periodically adjust the game workload prediction based on the feedback from recent prediction errors. Although such control-theoretic feedback mechanisms have been widely applied to predict the workload of video decoding applications, they heavily rely on estimating the queue lengths of video frame buffers. Given the interactive nature of games -- where game frames cannot be buffered - the control-theoretic DVS schemes for video applications can no longer be applied. Our main contribution is to suitably adapt these schemes for interactive games. Compared to history-based workload prediction schemes - where the workload of a game frame is predicted by averaging the workload of the previously-rendered frames -- our proposed scheme yields significant improvement on different platforms (e.g. a laptop and a PDA) both in terms of energy savings as well as output quality.
Efficient fume diffusion spotting in heterogeneous sensor networks
Authors: Xiaoning Cui, Qing Li, Baohua Zhao
Venue: Proceeding of the 1st ACM international workshop on Heterogeneous sensor and actor networks (2008)

Recent studies of sensor networks concerning large-scale issues and the diverse nature of real-world context have witnessed the debate on homogeneous and heterogeneous sensor networks recently. In this paper, a fume-diffusion-spotting sensor network is investigated based on heterogeneous sensor collaboration, giving inspiration for a suite of similar event-diffusion-monitoring applications. In our heterogeneous sensor network, the energy consumption and the sensitivity of diffusion spotting are tested, with the results showing notable advantage compared to the homogeneous network. The scalability performance is also considered and verified through experiment.
UNIX Shell Scripting Interview Questions, Answers, and Explanations: UNIX Shell Certification Review
Authors: Terry,  Sanchez-Clark
Venue:  (2007)

Fluency with a UNIX Shell is mandatory for working within the UNIX operating system. Keeping current, however, can be a challenge. With the UNIX Shell Scripting Interview Guide, you will be sure to be current. Using this book to prepare for a job interview or brush up on a scripting programming language will aid any programmer in acquiring new and applicable skills and knowledge. This book contains a complete reference of common scripting errors, performance tuning examples, and common applications. More than just UNIX documentation and open source rhetoric, this guide explains UNIX Shell Scripting from the perspective of the advanced programmer and administrator so you can be sure to come to any interview prepared. Key topics include: . Graphical user interfaces for UNIX . Advanced features of Bash, Bourne, and Korn . Common errors and troubleshooting . System monitoring and maintenance . Modern command line shells
Modelling Security Properties in a Grid-based Operating System with Anti-Goals
Authors: Alvaro Arenas, Benjamin Aziz, Juan Bicarregui, Brian Matthews, Erica Y. Yang
Venue: Proceedings of the 2008 Third International Conference on Availability, Reliability and Security (2008)

In this paper, we discuss the use of formal requirements-engineering techniques in capturing security requirements for a Grid-based operating system. We use KAOS goal model to represent two security goals for Grid systems, namely authorisation and single-sign on authentication. We apply goal-refinement to derive security requirements for these two security goals and we develop a model of anti-goals and show how system vulnerabilities and threats to the security goals can arise from such anti-models.
Peer-to-Peer Desktop Grids in the Real World: The ShareGrid Project
Authors: Cosimo Anglano, Massimo Canonico, Marco Guazzone, Marco Botta, Sergio Rabellino, Simone Arena, Guglielmo Girardi
Venue: Proceedings of the 2008 Eighth IEEE International Symposium on Cluster Computing and the Grid (2008)

ShareGrid is a peer-to-peer desktop grid aimed at satisfying the computing needs of the small research laboratories located in the Piedmont area in Northern Italy. ShareGrid adopts a cooperative approach, in which each participant allows the other ones to use his/her own resources on a reciprocity basis. ShareGrid is based on the OurGrid middleware, that provides a set of mechanisms enabling participating entities to quickly, fairly, and securely share their resources. In this paper we report our experience in designing, deploying, and using ShareGrid, and we describe the applications using it, as well as the lessons we learned, the problems that still remain open, and some possible solutions to them.
Range Assignment Approximation Based on Steiner Tree in Ad Hoc Wireless Networks
Authors: Rashid Bin Muhammad
Venue: Proceedings of the 22nd International Conference on Advanced Information Networking and Applications (2008)

In this paper, we discuss the problem of introducing relay nodes in the given set of original nodes and assigning transmitting ranges to the nodes. The main contribution of this paper is the O(N log N) algorithm to relay nodes to the wireless network and 2-approximation to assign transmitting ranges to nodes (original and relay). The output of the algorithm is the minimal Steiner tree on the graph consists of terminal (original) nodes and relay (additional) nodes. The output of approximation is the range assignments to the nodes.
Entropy-Based Collaborative Detection of DDOS Attacks on Community Networks
Authors: Shui Yu, Wanlei Zhou
Venue: Proceedings of the 2008 Sixth Annual IEEE International Conference on Pervasive Computing and Communications (2008)

A community network often operates with the same Internet Service Provider domain or the virtual network of different entities who are cooperating with each other. In such a federated network environment, routers can work closely to raise early warning of DDoS attacks to void catastrophic damages. However, the attackers simulate the normal network behaviors, e.g. pumping the attack packages as Poisson distribution, to disable detection algorithms. It is an open question: how to discriminate DDoS attacks from surge legitimate accessing. We noticed that the attackers use the same mathematical functions to control the speed of attack package pumping to the victim. Based on this observation, the different attack flows of a DDoS attack share the same regularities, which is different from the real surging accessing in a short time period. We apply information theory parameter, entropy rate, to discriminate the DDoS attack from the surge legitimate accessing. We proved the effectiveness of our method in theory, and the simulations are the work in the near future. We also point out the future directions that worth to explore in the future.
Achieving oblivious transfer using weakened security assumptions
Authors: C. Crepeau, J. Kilian
Venue: Proceedings of the 29th Annual Symposium on Foundations of Computer Science (1988)

The authors present some general techniques for establishing the cryptographic strength of a wide variety of games. As case studies, they analyze some weakened versions of the standard forms of oblivious transfer. They also consider variants of oblivious transfer that are motivated by coding theory and physics. Among their results, they show that a noisy telephone line is in fact a very sophisticated cryptographic device. They also present an application to quantum cryptography.
Determining termhood for learning domain ontologies using domain prevalence and tendency
Authors: Wilson Wong, Wei Liu, Mohammed Bennamoun
Venue: Proceedings of the sixth Australasian conference on Data mining and analytics - Volume 70 (2007)

In the course of reviewing existing automatic termrecognition techniques for applications in ontology learning, we came across four issues which can be improved upon. We proposed a new mechanism that incorporates both statistical and linguistic evidences for the computation of a final weight defined as Termhood (TH) for ranking term candidates. The analysis of the frequency distributions of the term candidates during our initial experiments revealed three advantages for higher quality term recognition.