ppxscal/embedding_network huggingface dataset:
An Internet scale simulation setup for BGP
Authors: Fang Hao, Pramod Koppol
Venue: ACM SIGCOMM Computer Communication Review (2003)

BGP convergence issues in the Internet have been extensively studied in recent years. It has been shown through formal analysis that BGP convergence is not always guaranteed. When it does converge, active measurement based techniques have determined that the convergence process may take upto 15 minutes while also causing intermittent packet loss/latency. As BGP enhancements are explored to address this convergence problem, controlled simulation experiments offer the most convenient and feasible mechanism to compare the efficacy of enhanced BGP procedures with respect to the current protocol mechanisms. Since the convergence behavior can be significantly influenced by network topology, it is desirable to use large Internet like topologies in such controlled simulations.In this paper, we present first steps towards realizing a large scale BGP simulation environment for reasoning about current BGP procedures and also for evaluating the efficacy of BGP protocol enhancements.
Binary and multicategory classification accuracy of the LSA machine
Authors: Georgios Lappas, Vivian Ambrosiadou
Venue: Proceedings of the international conference on Computational methods in sciences and engineering (2003)

The LSA machine is an effective method for predicting a class from linear separable data. LSA machine is based on the combination of Logarithmic Simulated Annealing with the Perceptron Algorithm. In this paper we present and compare the classification accuracy of the LSA machine on two medical databases a) the Winsconsin Breast Cancer Database, which is a binary database with two associated classes and b) the Diabetic Patient Management Database, which is a multicategory database with four associated classes. Many researchers use the Winsconsin Breast Cancer Database (WBCD) database, as a benchmark database for testing their systems. The WBCD database consists of 699 samples with 9 input attributes, The LSA machine is trained on 50% and 75% of the entire dataset and in both cases we obtain a classification accuracy of 98.8% on the remaining samples. This classification accuracy on the test set of samples, to our best of knowledge is the highest reported in the literature. The Diabetic Patient Management database consists of 746 samples with 18 input values and an associated class label denoting one of the four treatments for the patient. The LSA machine for comparison reasons is trained on the 646 samples of the database, obtaining stable classification accuracy over 74% for all four classes, with highest classification accuracy of 87%.
An advanced signal processing toolkit for JAVA applications
Authors: V. P. Shah, N. H. Younan, T. Alford, A. Skjellum
Venue: Proceedings of the 2nd international conference on Principles and practice of programming in Java (2003)

This paper examines the capability, performance, and relevance of a signal processing toolkit in Java, a programming language for Web-based applications. Due to the simplicity, ease and application use of the toolkit and with the advanced Internet technologies such as Remote Method Invocation (RMI), a spectral estimation applet has been created in the Java environment. This toolkit also provides an interactive and visual approach in understanding the various theoretical concepts of spectral estimation and shows the need to create more application applets to better understand the various concepts of signal and image processing.
Engineering Optimization Using a Simple Evolutionary Algorithm
Authors: Efrén Mezura-Montes, Carlos A. Coello Coello, Ricardo Landa-Becerra
Venue: Proceedings of the 15th IEEE International Conference on Tools with Artificial Intelligence (2003)

This paper presents a simple (1 + ¿) Evolution Strategy and three simple selection criteria to solve engineering optimization problems. This approach avoids the use of a penalty function to deal with constraints. Its main advantage is that it does not require the definition of extra parameters, other than those used by the evolution strategy. A self-adaptation mechanism allows the algorithm to maintain diversity during the process in order to reach competitivesolutions at a low computational cost. The approach was tested in four well-known engineering design problems and compared against several penalty-function-based approaches and other state-of-the-art technique. The results obtained indicate that the proposed technique is highly competitive in terms of quality, robustness and computational cost.
General approach to conformal mappings used in atmospheric modeling
Authors: A. Bourchtein, L. Bourchtein, E. R. Oliveira
Venue: Applied Numerical Mathematics (2003)

A class of conformal separable variable mappings is introduced to generalize different conformal projections used in atmospheric modeling and cartography for representation of spherical regions. It is shown that conformal stereographic, conic and cylindrical projections are special cases of this class of mappings. A second approach based on composition of conformal mappings is used to describe the set of all conformal transformations from a sphere onto a plane. Under a natural assumption about the independence of the map factor from longitude a theorem of equivalence between the two above classes of conformal mappings is proved. A problem of minimization of the map factor variation within the constructed set of mappings is considered. A comparison of the map factor for different kinds of mappings (polar and oblique stereographic, conic and cylindrical) is performed based on analytical and numerical evaluations.
Interactive Stereoscopic Rendering of Volumetric Environments
Authors: Ming Wan, Nan Zhang, Huamin Qu, Arie E. Kaufman
Venue: IEEE Transactions on Visualization and Computer Graphics (2004)

Abstract--We present an efficient stereoscopic rendering algorithm supporting interactive navigation through large-scale 3D voxel-based environments. In this algorithm, most of the pixel values of the right image are derived from the left image by a fast 3D warping based on a specific stereoscopic projection geometry. An accelerated volumetric ray casting then fills the remaining gaps in the warped right image. Our algorithm has been parallelized on a multiprocessor by employing effective task partitioning schemes and achieved a high cache coherency and load balancing. We also extend our stereoscopic rendering to include view-dependent shading and transparency effects. We have applied our algorithm in two virtual navigation systems, flythrough over terrain and virtual colonoscopy, and reached interactive stereoscopic rendering rates of more than 10 frames per second on a 16-processor SGI Challenge.
Object-based analysis and interpretation of human motion in sports video sequences by dynamic Bayesian networks
Authors: Ying Luo, Tzong-Der Wu, Jenq-Neng Hwang
Venue: Computer Vision and Image Understanding (2003)

In this paper, we present a novel scheme for object-based video analysis and interpretation based on automatic video object extraction, video object abstraction, and semantic event modeling. In our proposed scheme, video objects (VOs) are first segmented, followed by a video object abstraction algorithm for identifying key frames to reduce data redundancy and provide reliable feature data for next stage of the algorithm. Semantic feature modeling scheme is based on temporal variation of low-level features extracted from VOs. More specifically, the Dynamic Bayesian Network (DBN) is used to characterize the spatio-temporal nature of the semantic objects. Comparing to a hidden Markov model (HMM), the DBN framework can provide a detailed description of the characteristics of VOs, which can be readily interfaced to MPEG-7 application. Experimental results that demonstrate the effective performance of the proposed approach are also presented.
Netscript: a programming language for packet-stream processing
Authors: Yechiam Yemini
Venue:  (2003)

The central goal of this dissertation is to introduce a general-purpose language-based system called NetScript to simplify the development, deployment, and management of protocol and service software in a computer networks, specifically programmable or active networks. NetScript is the first system to: (1) Introduce a high-level dataflow language to program processing of packet flows, including protocols and services; (2) Integrate constructs for packet syntax declaration, classification and processing, as well as composition of packet processing modules, to unify and simplify the construction of communications software; (3) Introduce compiler-generated instrumentation of network services to simplify and unify their management; (4) Support dynamic deployment and composition of distributed flow processing modules, implementing end-to-end services on active or programmable networks. NetScript views network protocol processing in analogy the PostScript paradigm. PostScript views a printer as a programmable printing engine that executes page-descriptions. Similarly, NetScript views a network node as a programmable processing engine that executes programs that process packet of a programmable, networked engine. Whereas, currently protocol software must be re-written for each architecture, NetScript programs can run unmodified on heterogeneous architectures and platforms. NetScript enables rapid evolution of network technologies by creating a dynamically programmable infrastructure, one that can be flexibly extended with new or enhanced services. Specifically, NetScript defines a novel programming model for programming services on active or programmable [1&ndash;3] networks. NetScript programs can be dispatched to nodes in a network to dynamically extend the network with new protocols and services. Its programs are dataflow components that perform primitive operations on packet-streams. NetScript simplifies and automates essential components of network management. Currently, network management instrumentation must be designed and specified by committee separate from protocol design and implementation. This is a process that can take several years. NetScript unifies and automates the creation of management instrumentation at design-, implementation-, and compile-time. NetScript has proven useful for implementing a variety of networked applications. Example applications are IP routers, firewalls, protocol analyzers, network address translators, traffic shapers, queuing disciplines, intrusion detection systems, transport protocols and IP telephony systems.
Can Online Behavior Unveil Deceivers? -- An Exploratory Investigation of Deception in Instant Messaging
Authors: Lina Zhou, Dongsong Zhang
Venue: Proceedings of the Proceedings of the 37th Annual Hawaii International Conference on System Sciences (HICSS'04) - Track 1 - Volume 1 (2004)

Deception has been extensively studied in many disciplines in social science. With the increasing use of instant messaging (IM) in both informal communication and performing tasks in work place, deception in IM is emerging as an important issue. In this study, we aimed to explore the online behavior of deception in a group IM setting. The empirical results from triadic groups showed that two types of online behavior under investigation could significantlydifferentiate deceivers from truth-tellers. The findings can potentially broaden our knowledge of behavioral indicators of deception in human interaction and improve deception detection in cyberspace.
Resource efficient approaches in wireless networking
Authors: Ding-Zhu Du
Venue:  (2003)

This thesis proposes algorithms to solve several problems related to energy efficiency in ad hoc wireless networks and wireless sensor networks. Designing mechanisms that efficiently use energy resources impacts the network lifetime and the performance of the application. Wireless ad-hoc sensor networks are characterized by a large number of sensors remotely deployed in the field for phenomena observation. As the number of sensors deployed is greater than the optimum required, one method to reduce energy consumption is to schedule the sensor node activities to alternate between active and sleep rnode of operations. We propose solutions for sensor scheduling mechanism with regard to Target Surveillance and Area Monitoring applications. Theoretical results and simulations are presented for these approaches. A novel approach for routing traffic in ad-hoc wireless networks employs a virtual backbone responsible for performing the routing protocol. Limiting the number of nodes actively participating in routing reduces communication and saves the power consumed in receiving and processing redundant information. In this thesis we address the problem of selecting nodes for the virtual backbone, approximated by a minimum connected dominating set in unit-disk graphs. For this NP-hard problem, we designed an efficient distributed approximation algorithm and studied its performances through simulation. In this thesis, we also consider the problem of extending the wireless network lifetime when n nodes have fixed position and up to k additional relay nodes can be placed at arbitrary locations such that the length of the longest edge in the interconnecting network is minimized. Thus the maximum node transmission power is minimized, prolonging the time until the first node drains its battery resources, breaking the network connectivity. We modeled this problem as the bottleneck Steiner tree problem and propose an approximation algorithm with performance ratio 3 + &epsiv; for the Euclidean plan, where &epsiv; is an arbitrary positive number. Finally, we address the range assignment problem, concerned with maintaining a strongly connected topology while minimizing the total energy consumption. We propose an optimization algorithm for any spanning tree based topology and apply it to the minimum spanning tree and topology incremental power structures.
Quality of service support for wireless networks
Authors: Ilhwan Kim
Venue:  (2003)

This dissertation addresses the issue of Quality of Service (QoS) support for wireless networks, especially IEEE802.11 wireless LANs, having time-varying capacity which makes the QoS support problem difficult. To provide guarantees of QoS parameters such as delay violation probability, packet loss probability due to buffer overflow, etc., for the wireless networks, we need to take into account not only input traffic characteristics, but also time-varying wireless channel characteristics. Considering the wireless channel characteristics, with the theoretical tool of large deviation theory we analyze the wireless Generalized Processor Sharing (GPS) scheme to provide stochastic performance guarantees for wireless LANs through the PCF mode which is based on a polling scheme, and propose connection admission schemes to admit as many connections as possible while satisfying QoS requirements of each connection. To increase the throughput and delay performance of the best-effort traffics such as the TCP traffics flowing through the wireless LANs we propose the H&infin; AQM scheme for the congested queue which resides in the AP station, facing the wireless networks with time-varying channel capacity. We show superior performance of the proposed scheme in comparison with the ABED scheme through ns simulation results. For the cases where traffic or channel models are not available, we propose the adaptive bandwidth allocation scheme and the relative differentiated service architecture for wireless LANs, and show the experimental results obtained from the testbed in which the proposed schemes were implemented.
Autocorrelation and the Enumeration of Strings Avoiding a Fixed String
Authors: Kimmo Eriksson
Venue: Combinatorics, Probability and Computing (1997)

Considering strings over a finite alphabet &Ascr;, say that a string is w-avoiding if it does not contain w as a substring. It is known that the number aw(n) of w-avoiding strings of length n depends only on the autocorrelation of w as defined by Guibas&ndash;Odlyzko. We give a simple criterion on the autocorrelations of w and w&prime; for determining whether aw(n) > aw&prime;(n) for all large enough n.
State-Preserving vs. Non-State-Preserving Leakage Control in Caches
Authors: Yingmin Li, Dharmesh Parikh, Yan Zhang, Karthik Sankaranarayanan, Mircea Stan, Kevin Skadron
Venue: Proceedings of the conference on Design, automation and test in Europe - Volume 1 (2004)

This paper compares the effectiveness of state-preserving and non-state-preserving techniques for leakage control in caches by comparing drowsy cache and gated-Vss for data caches using 70nm technology parameters. To perform the comparison, we introduce "HotLeakage", a new architectural model for subthreshold and gate leakage that explicitly models the effects of temperature, voltage, and parameter variations, and has the ability to recalculate leakage currents dynamically as temperature and voltage change at runtime due to operating conditions, DVS techniques, etc.By comparing drowsy-cache and gated-Vss at different L2 latencies and different gate oxide thickness values, we are able to identify a range of operating parameters at which gated-Vss is more energy efficient than drowsy-cache, even though gated-Vss does not preserve data in cache lines that have been deactivated. We are also able to show potential further benefits of gated-Vss if an effective dynamic adaptation technique can be found. These results debunk a fairly widespread beliefthat state-preserving techniques are inherently superior to non-state-preserving techniques.
Physical Objects as Bidirectional User Interface Elements
Authors: Dan Rosenfeld, Michael Zawadzki, Jeremi Sudol, Ken Perlin
Venue: IEEE Computer Graphics and Applications (2004)

The Planar Manipulator Display uses physical objects for human¿computer interaction. This system addresses the poor match between standard computer interfaces and human spatial awareness.
Maximizing job completions online
Authors: Bala Kalyanasundaram, Kirk R. Pruhs
Venue: Journal of Algorithms (2003)

We consider the problem of maximizing the number of jobs completed by their deadline in an online single processor system where the jobs are preemptable and have release times. So in the standard three field scheduling notation, this is the online version of the problem 1 |ri; pmtn| Σ(1 - Ui). We present a deterministic algorithm Lax, and show that for every instance I, it is the case that either Lax, or the well-known deterministic algorithm SRPT (Shortest Remaining Processing Time), is constant competitive on I. An immediate consequence of this result is a constant competitive randomized algorithm for this problem. It is known that no constant competitive deterministic algorithm exists for this problem.
High Technology War and 'Surgical Strikes'
Authors: A. K. Bissett
Venue: ACM SIGCAS Computers and Society (2003)

The involvement of computers in modern weaponry is considerable, especially in efforts to improve accuracy. This question of accuracy, and the discourse of 'surgical strikes' associated with high technology weapons in modern war, are examined. Drawing upon the writings of Carl von Clausewitz, the misleading and often dangerous implications of this ideology are discussed. We question whether the fundamental nature of war has changed. 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
Automatic text categorization in terms of genre and author
Authors: Efstathios Stamatatos, George Kokkinakis, Nikos Fakotakis
Venue: Computational Linguistics (2000)

The two main factors that characterize a text are its content and its style, and both can be used as a means of categorization. In this paper we present an approach to text categorization in terms of genre and author for Modern Greek. In contrast to previous stylometric approaches, we attempt to take full advantage of existing natural language processing (NLP) tools. To this end, we propose a set of style markers including analysis-level measures that represent the way in which the input text has been analyzed and capture useful stylistic information without additional cost. We present a set of small-scale but reasonable experiments in text genre detection, author identification, and author verification tasks and show that the proposed method performs better than the most popular distributional lexical measures, i.e., functions of vocabulary richness and frequencies of occurrence of the most frequent words. All the presented experiments are based on unrestricted text downloaded from the World Wide Web without any manual text preprocessing or text sampling. Various performance issues regarding the training set size and the significance of the proposed style markers are discussed. Our system can be used in any application that requires fast and easily adaptable text categorization in terms of stylistically homogeneous categories. Moreover, the procedure of defining analysis-level markers can be followed in order to extract useful stylistic information using existing text processing tools.
On the radon transform of sampled functions
Authors: Roger W. Brockett
Venue:  (2003)

We address the characterization of the Radon transform of piecewise constant functions on a pixel lattice. A closed-form expression is derived for the Radon transform of any pixelated function and the pixelated line analyzed in detail. The latter is shown to have three properties that lead to a Radon transform substantially different from that of the idealized line: bounded support, non-zero width, and pixelization. Bounded support results in two sets (the admissible and the intersecting set) that fully characterize the support of the range function, while non-zero width shapes its amplitude to be continuously decaying, from the maximum value, at a rate 1/sin(&Delta;&thetas;) (where &Delta;&thetas; is the distance to the angle associated with the maximum). These observations enable the derivation of the narrow strip approximation (NSA) to the Radon transform of the pixelated line. This is an upper-bound on the true Radon transform which is shown to be tight, in the sense that inequalities become equalities, when the ratio between pixel and image size goes to zero. The NSA is a simple model of the range function that, unlike the frequently used Dirac delta, accounts for the three properties mentioned above. In result, it allows both theoretical and algorithmic advances to the problem of line detection. On the theoretical side, it is shown that the traditional strategy of line detection by thresholding is fundamentally flawed, as it is intrinsically unable to reach accurate parameter estimates for spatially localized lines. On the algorithmic side, an analysis-by-synthesis line detection algorithm is proposed and shown to be substantially more accurate than thresholding methods. Finally, we characterize various statistical properties of the range function: its probability density function, mean, variance, and sample mean. Once again this leads to advances in both theory and algorithms: (1) a proof of existence of a fundamental law that characterizes the amplitudes of the Radon transform, and (2) an optimal, in the minimum probability of error sense, algorithm for estimating the number of lines in an image.