ppxscal/embedding_network huggingface dataset:
Computational improvements in the substitution method for bounding percolation thresholds
Authors: John C. Wierman
Venue:  (2005)

The substitution method has proven to be an effective tool for bounding the critical probability of a variety of percolation models. Nevertheless, until recently substitution method calculations have been done by hand. This has severely restricted the size of computationally feasible substitution regions. We examine the computational problems posed by the substitution method, beginning with an analysis of the component calculations. We seek to better understand the nature of the computational problem, hoping that better understanding will lead to improvements. Our goal is a little different from that of most algorithmic investigations. Since the substitution method constitutes a proof, there is little reason to perform a particular computation more than once. We use each speed improvement to attempt a new, larger computation that will lead to tighter bounds on the critical probability. Our major results can be grouped into two categories: recognition of links between substitution method calculations and well-known results in other areas of mathematics, and the development of novel algorithms to exploit special structure. The links to other areas of mathematics include the use of 2-attached graphs to compute partition polynomials, the use of network flow techniques to prove stochastic ordering on a partially ordered set, and the use of the Lerchs and Grossmann algorithm to address the parametric problem more efficiently. The novel techniques we introduce are the use of symmetry to reduce the size of the calculation, and the use of non-crossing partitions. The exploitation of symmetry often makes the difference between a calculation that is feasible versus one that is not. Non-crossing partitions take advantage of planarity of a substitution region. We also show that key parts of the computation have running times that grow superexponentially in the substitution region size. While our improved calculation still experiences super-exponential growth, our improvements enable us to solve much larger problems than before. Thus we have been able to significantly improve bounds on the critical probability for our challenge problems: the Kagom&eacute; bond model, the (3,122) bond model, and the hexagonal site model.
Video Management in Peer-to-Peer Systems
Authors: Ying Cai, Zhan Chen, Wallapak Tavanapong
Venue: Proceedings of the Fifth IEEE International Conference on Peer-to-Peer Computing (2005)

Providing scalable video services in a peer-to-peer (P2P) environment is challenging. Since videos are typically large and require high communication bandwidth for delivery, many peers may be unwilling to cache them in whole to serve others. In this paper, we address two fundamental research problems in providing scalable P2P video services, namely (1) how a host can find enough video pieces, which may scatter among the whole system, to assemble a complete video, and (2) given a limited buffer size, what part of a video a host should cache. We propose a new distributed video management technique. Our scheme organizes hosts into a number of cells, each of which is a distinct set of hosts which together can supply a video in its entirety. A client looking for a video can stop its search as soon as it finds a host that caches any part of the video. Caching operations can be coordinated within each cell to balance data redundancy in the system. Our extensive study on a Gnutella-like simulation network shows convincingly the performance advantage of the new scheme.
Recursive optimization-simulation modeling for the analysis of ambulatory health care facilities
Authors: Dean H. Kropp, John C. Hershey
Venue: ACM SIGSIM Simulation Digest (1979)

The overall planning problem of an ambulatory health care facility is often attacked using either linear programming or simulation models. This paper discusses each method and then describes a third method -- recursive modeling -- which capitalizes on the advantages and minimizes the disadvantages of the other two methods. Methods of variance reduction and data analysis are also discussed.
Checking Inside the Black Box: Regression Testing by Comparing Value Spectra
Authors: Tao Xie, David Notkin
Venue: IEEE Transactions on Software Engineering (2005)

Comparing behaviors of program versions has become an important task in software maintenance and regression testing. Black-box program outputs have been used to characterize program behaviors and they are compared over program versions in traditional regression testing. Program spectra have recently been proposed to characterize a program's behavior inside the black box. Comparing program spectra of program versions offers insights into the internal behavioral differences between versions. In this paper, we present a new class of program spectra, value spectra, that enriches the existing program spectra family. We compare the value spectra of a program's old version and new version to detect internal behavioral deviations in the new version. We use a deviation-propagation call tree to present the deviation details. Based on the deviation-propagation call tree, we propose two heuristics to locate deviation roots, which are program locations that trigger the behavioral deviations. We also use path spectra (previously proposed program spectra) to approximate the program states in value spectra. We then similarly compare path spectra to detect behavioral deviations and locate deviation roots in the new version. We have conducted an experiment on eight C programs to evaluate our spectra-comparison approach. The results show that both value-spectra-comparison and path-spectra-comparison approaches can effectively expose program behavioral differences between program versions even when their program outputs are the same, and our value-spectra-comparison approach reports deviation roots with high accuracy for most programs.
Semantic knowledge extraction and annotation for web images
Authors: Zhigang Hua, Xiang-Jun Wang, Qingshan Liu, Hanqing Lu
Venue: Proceedings of the 13th annual ACM international conference on Multimedia (2005)

Nowadays, images have become widely available on the World Wide Web (WWW). It's essential to develop effective ways for managing and retrieving such abundant images. Advantageously, compared to the traditional images where very little information is provided, the web images contain plentiful context data. This paper introduces a system that can automatically acquire semantic knowledge for web image annotation. By using a page layout analysis method that can precisely assign context to web images, we developed efficient algorithms to extract semantic knowledge for web images, such as description, people, temporal and geographic information. To validate the practicality and efficiency of this system, we applied it to about 6,500 images crawled from Web. Experiments demonstrated that our approach could achieve satisfactory results.
Systems hierarchy as a basis for simulation model description
Authors: Bernard P. Zeigler
Venue: ACM SIGSIM Simulation Digest (1984)

This paper elaborates an integrated hierarchy of model description formalisms previously proposed. We discuss the advantages of the hierarchical approach vis a vis a standardized universal model description language. Among the principal advantages are the opportunities provided for concise model specification while at the same time enabling equivalence testing of models expressed in diverse formalisms. 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
Nonlinear Dynamical Analysis of Normal Voices
Authors: Maria Eugenia Dajer, Jose Carlos Pereira, Carlos Dias Maciel
Venue: Proceedings of the Seventh IEEE International Symposium on Multimedia (2005)

Human voice has been the focus of study for different areas of sciences. Researches in the last two decades have established the existence of chaos in human voice production. The purpose of this paper is to use nonlinear dynamics methods in the analysis of normal voices from healthy subjects and correlate them to traditional acoustic parameters as well as perceptual analysis. Twelve human voice signals from healthy subjects, 6 males and 6 females, ranging in age from 19 to 39 years old were used. Sustained vowel sounds /a/, /e/ and /i/, from brazilian Portuguese were recorded at a sampling rate of 22,050 Hz and analyzed in order to obtain acoustic perturbation measures (jitter, shimmer, coefficient of excess - EX, and Pitch amplitude - PA). The phase space reconstruction method was used to describe the nonlinear dynamic characteristics of voice signal samples. This paper shows that non-linear dynamical methods as phase space reconstruction seems to be a suitable technique for voice signals analysis, due to the chaotic component of the human voice. The results suggest that non-linear dynamic analysis does not replace existing techniques instead, they may improve and complement the recent voice analysis methods available for health professionals, speech therapist and clinician.
Some Remarks on Computing Consistent Extensions of Dynamic Information Systems
Authors: Zbigniew Suraj, Krzysztof Pancerz
Venue: Proceedings of the 5th International Conference on Intelligent Systems Design and Applications (2005)

The aim of this paper is to present some remarks on computingmaximal consistent extensions of dynamic information systems.Dynamic information systems can be used as a tool for description of concurrent systems. In this case, they include the knowledge about global states and transitions between them observed in given concurrent systems. The task of creating a maximal consistent extension is to find all global states and all transitions between them which are consistent with the knowledge included in data tables representing a dynamic information system. A method for computing such an extension is given. The method presented here seems to be more ef- ficient than methods presented earlier in the literature. Our approach is based on the rough set theory.
Butterfly Effect: An Augmented Reality Puzzle Game
Authors: Marleigh Norton, Blair MacIntyre
Venue: Proceedings of the 4th IEEE/ACM International Symposium on Mixed and Augmented Reality (2005)

Butterfly Effect is a 3D puzzle game using augmented reality. The key motivation was to create a game that leverages the structure of the physical world during gameplay without requiring the computer to have a detailed model of the space. The butterflies are virtual, but the space the player navigates is physical. The player travels her environment, collecting the butterflies. For butterflies that are out of reach, the player can rotate the virtual world in 90 degree chunks about an arbitrary axis to bring them to an accessible location.
A Convex Quadratic Characterization of the Lovász Theta Number
Authors: Carlos J. Luz, Alexander Schrijver
Venue: SIAM Journal on Discrete Mathematics (2005)

In previous works an upper bound on the stability number $\alpha(G)$ of a graph G based on convex quadratic programming was introduced and several of its properties were established. The aim for this investigation is to relate theoretically this bound (usually represented by $\upsilon(G)$) with the well-known Lovász $\vartheta(G)$ number. First, a new set of convex quadratic bounds on $\alpha(G)$ that generalize and improve the bound $\upsilon(G)$ is proposed. Then it is proved that $\vartheta(G)$ is never worse than any bound belonging to this set of new bounds. The main result of this note states that one of these new bounds equals $\vartheta(G)$, a fact that leads to a new characterization of the Lovász theta number.
A new geographic process data model
Authors: Femke Emma Reitsma
Venue:  (2005)

Processes, although the subject matter of geography, have not been represented in a manner that aids their querying and analysis. This dissertation develops an appropriate data model that allows for such a process oriented representation, which is built upon a theory of process. The data model, called nen, focuses existing modeling approaches on representing and storing process information. The flux simulation framework was created utilizing the nen data model to represent processes; it extends the Repast agent based modeling environment. This simulator includes basic classes for developing a domain specific simulation and a set of query tools for inquiring after the results of a simulation. The methodology was then prototyped with a watershed runoff simulation.
Reasoning about real-time statecharts in the presence of semantic variations
Authors: Subash Shankar, Sinan Asa, Vladimir Sipos, Xiaowei Xu
Venue: Proceedings of the 20th IEEE/ACM international Conference on Automated software engineering (2005)

This paper describes a framework that allows for reasoning about and verification of concurrent statecharts with real-time constraints subject to semantic variations. The major problems addressed by this paper include the capture of multiple semantic variations of real-time statecharts, and the use of the resulting semantics for further analysis. Our solution is based on a theoretical framework involving a two-dimensional temporal logic that is used to independently capture flow of control through statecharts as well as flow of time. The independence of these dimensions, along with the high-level nature of temporal logic allows for simple adaptation to alternate semantics of statecharts as well as real-time models. The paper defines our logic, shows how the semantics of real-time statecharts can be expressed in this formalism, and describes our tools for capturing and reasoning about these semantics. The underlying goal is the formal analysis of real-time software behavior in a way that captures designer intentions.
Hierarchy-Regularized Latent Semantic Indexing
Authors: Yi Huang, Kai Yu, Matthias Schubert, Shipeng Yu, Volker Tresp, Hans-Peter Kriegel
Venue: Proceedings of the Fifth IEEE International Conference on Data Mining (2005)

Organizing textual documents into a hierarchical taxonomy is a common practice in knowledge management. Beside textual features, the hierarchical structure of directories reflect additional and important knowledge annotated by experts. It is generally desired to incorporate this information into text mining processes. In this paper, we propose hierarchy-regularized latent semantic indexing, which encodes the hierarchy into a similarity graph of documents and then formulates an optimization problem mapping each document into a low dimensional vector space. The new feature space preserves the intrinsic structure of the original taxonomy and thus provides a meaningful basis for various learning tasks like visualization and classification. Our approach employs the information about class proximity and class specificity, and can naturally cope with multi-labeled documents. Our empirical studies show very encouraging results on two real-world data sets, the new Reuters (RCV1) benchmark and the Swissprot protein database.
Determining the proper response to online extortion
Authors: Anne Payton
Venue: Proceedings of the 2nd annual conference on Information security curriculum development (2005)

Since business functions in a virtual world, many feel that online business crimes must be handled in a new way. These crimes are too often treated as an IT problem to be solved internally with proper procedures and technology. Putting security tools and practices in place is crucial, but online crime, like the offline version, shouldn't be handled alone. The only solution to this growing problem is to build up internal protections, then work with industry peers and law enforcement to build a common defense. This paper analyzes the most common forms of online extortion, and the most effective responses to them.
Execution Model for Outsourced Corrective Maintenance
Authors: Baru S. Rao, N. L. Sarda
Venue: Proceedings of the The Fifth International Conference on Computer and Information Technology (2005)

We focus on corrective maintenance carried out in the outsourced mode under strict service level agreements and present the characteristics of the problem and the activities performed. We detail the information requirements for various maintenance services, such as, emergency maintenance, production support, and corrective maintenance. We present the concept of a system execution model with its constituent nodes and arcs and present the steps to build the same. We present a case study of a large commercial outsourcing project to demonstrate how the execution model can help in making quick decisions that will reduce the turn around times of corrective maintenance requests.
Facial action tracking using particle filters and active appearance models
Authors: Soumya Hamlaoui, Franck Davoine
Venue: Proceedings of the 2005 joint conference on Smart objects and ambient intelligence: innovative context-aware services: usages and technologies (2005)

Tracking a face and its facial features in a video sequence is a challenging problem in computer vision. In this view, we propose a stochastic tracking system based on a particle- filtering scheme. In this paradigm, the unobserved state includes global face pose and appearance parameters coding both shape and texture information of the face. The adopted observations distribution is derived from an Active Appearance Model (AAM). The transition distribution and the particles number are adaptive in the sense that they are guided by an AAM deterministic search. This optimization stage adjusts the explored area of the state space to the quality of the prediction and enables a substantial gain in computing time. The observation model uses a robust distance measure in order to account for occlusions. Experiments on real video show encouraging results.
mSSL: Extending SSL to Support Data Sharing Among Collaborative Clients
Authors: Jun Li, Xun Kang
Venue: Proceedings of the 21st Annual Computer Security Applications Conference (2005)

Client-server applications often do not scale well when a large number of clients access a single server. To solve this, a new trend is to allow a client to download data from other peer clients, in addition to from the server directly. This paradigm, which we call the hybrid peer-to-peer paradigm, is friendly to the server's scalability, but also faces new security challenges. For example, how can the server authenticate its clients and support data confidentiality? How can a client trust the data downloaded from other clients? What if a client refuses to acknowledge the service it received or overstates the service it offered? In this paper, we present a protocol, called mSSL, that provides a set of security functions to enable secure sharing of the data of a server among its clients. In addition to access control and confidentiality support, mSSL provides an original design on supporting data integrity and proof of service in this new context. Our evaluation further shows that mSSL has a reasonable overhead.
A constructive proof of Ky Fan's generalization of Tucker's lemma
Authors: Timothy Prescott, Francis Edward Su
Venue: Journal of Combinatorial Theory Series A (2005)

We present a proof of Ky Fan's combinatorial lemma on labellings of triangulated spheres that differs from earlier proofs in that it is constructive. We slightly generalize the hypotheses of Fan's lemma to allow for triangulations of Sn that contain a flag of hemispheres. As a consequence, we can obtain a constructive proof of Tucker's lemma that holds for a more general class of triangulations than the usual version.
Designing a High Performance and Low Energy-Consuming Embedded System with Considering Code Compressed Environments
Authors: Ching-Wen Chen, Chang-Jung Ku, Chih-Hung Chang
Venue: Proceedings of the 11th IEEE International Conference on Embedded and Real-Time Computing Systems and Applications (2005)

In this paper, we present an embedded system design which is cost-efficient and which considers performance improvement and power consumption based on the frequency with which instructions are executed. We use the locality of running programs to optimize the use of memory space, system performance, and power consumption; that is, we compress infrequently executed codes to save the use of memory space but compress (encode) frequently executed codes to power consumption and maximize performance. To save the number of memory access times, the frequently executed instructions are encoded as shorter code words and then the continuous code words are packed into a pseudo instruction. Once the decompression engine fetches one pseudo instruction, it can extract multiple instructions to reduce the number of memory access times. In addition, we also propose a design with multiple look-ahead tables that solves the problem which arises due to the reduction in instructions from one-time memory access which occurs because the great amount of frequently executed instructions. From our simulation results, our method with one 256-instruction look-ahead table does not increase the compression ratio, and the ratio of the power consumption can be reduced by about 47.23% than compressing all instructions. With regard to multiple look-ahead table methods, when one 512-instruction look-ahead table is used, the ratio of the power consumption is reduced by 37.25% only, however, when two look-ahead tables that contain 256 instructions in each table are used, the power consumption can be improved by 49.36%. According to the simulation results, our proposed methods based on the frequencies of executed instructions result in low power consumption, performance improvement and reduced memory space.
Enhanced Frame-Based Video Coding to Support Content-Based Functionalities
Authors: Prabhudev I. Hosur, Rolando A. Carrasco
Venue: Proceedings of the Sixth International Conference on Computational Intelligence and Multimedia Applications (2005)

This paper presents the enhanced frame-based video coding scheme that enables some useful content-based functionalities such as user-interactivity with video content, assignment of different quality to video objects, and content-based video search and retrieval. The input video source for the proposed enhanced frame-based video encoder consists of rectangular-size video frames and shapes of arbitrarily-shaped video objects in the frames. The rectangular frames are encoded using a scheme similar to the conventional frame-based video coding and the shapes of video objects are encoded using the contour-based vertex coding. It is possible to achieve several useful content-based functionalities by utilizing the shape information in the bitstreamat the cost of a very small overhead of shape bits.
A Unified MC-DCT Framework for Reducing the Computational Complexity of Frequency-Domain Transcoders for MPEG-2 Video
Authors: Deepak Nayak, Dipan Mehta, Uday Desai
Venue: Proceedings of the Seventh IEEE International Symposium on Multimedia (2005)

In order to transmit pre-encoded digital video over heterogeneous networks, it becomes necessary to employ transcoding techniques that convert pre-encoded video streams into streams having different bit rates and quality. Video transcoders save computational overheads incurred in the IDCT and DCT operations, by performing motion compensation (MC) in the frequency (block-DCT) domain (MC-DCT). Most of the computational complexity of the frequency-domain video transcoder comes from the MC-DCT operation. MC-DCT involves pre- and postmultiplication of 8 × 8 DCT blocks with 8 × 8 matrices derived from the motion vectors of that block. The specific contribution of this work is towards developing a unified framework for handling all MC-DCT modes for MPEG-2 video input to a frequency-domain video transcoder. Use of this framework can lead to a potential saving of up to fortyeight 8 × 8 block multiplications and sixteen 8 × 8 block additions per reconstructed 16 × 16 macroblock.