ppxscal/embedding_network huggingface dataset:
Where center of pressure should be controlled in biped upright posture
Authors: Satoshi Ito_aff1n2, Yoshihisa Saka, Haruhisa Kawasaki
Venue: Systems and Computers in Japan (2004)

The stability of the upright posture of the biped system on horizontal ground has been evaluated in terms of the vertical projection of the center of gravity on the ground. Since the point of projection coincides with the center of pressure of the ground reaction force (CoP), so long as static equilibrium is maintained, robust control can be realized if the ground reaction force is directly controlled. Consequently, we modeled the upright standing state of the biped system by a two-link system composed of the foot and the remainder and proposed a method of controlling the ground reaction force based on the output of the ankle joint. The method is equivalent to control of the CoP, but no detailed study of where the center should be controlled has been presented. This point is crucial if the foot is not symmetrical in the anterior&ndash;posterior direction, or if the ankle joint is located at a certain height, as in the case of humans. The purpose of this paper is to investigate this problem. Two control methods can be considered, depending on whether the evaluation criterion is defined as the minimum steady output of the ankle joint or as the stability margin. For each of the criteria, we analyze the stability and the steady-state posture. To clarify the criterion by which humans perform control, the CoP was measured for humans in the upright posture. The results suggest that humans are less likely to use the minimum output of the ankle joint as the evaluation criterion. &copy; 2004 Wiley Periodicals, Inc. Syst Comp Jpn, 35(5): 23&ndash;31, 2004; Published online in Wiley InterScience (). DOI 10.1002&sol;scj.10559
Iterative receivers for coded MIMO signaling: Invited Papers
Authors: Ezio Biglieri, Alessandro Nordio, Giorgio Taricco
Venue: Wireless Communications Mobile Computing (2004)

In this tutorial paper, we describe iterative receivers that combine a soft decoder for a general space-time code with a spatial-interference canceler. The performance of these receivers is analyzed by using EXIT charts, a convenient graphical description that yields quite accurate results. By properly combining the EXIT characteristics of the canceler and of the decoder, the convergence behavior of the iterative algorithms can be understood, and design guidelines derived. The idea here is to observe that both the interference canceler and the decoder can be studied by examining the evolution of the extrinsic information passed along to the connected blocks. Copyright &copy; 2004 John Wiley & Sons, Ltd.
The mathematics of programming and why we should teach it
Authors: David Gries
Venue: Journal of Computing Sciences in Colleges (2004)

Much of the work on program correctness and how it could influence programming was developed in the 1970's. Nevertheless, first-semester texts and even second-semester texts on programming don't touch the topic, or pay only lip service to it. The students, the CS curriculum, and the field lose out because of this. We produce inefficient hackers, who can't see the beauty in well-done, disciplined programming. CS already has its field of Computational Complexity; we should be teaching Computational Simplicity. In this lecture, we will try to show how correctness concerns can be integrated into our courses and the effect that the integration has.
Time-frequency analysis of mechanomyogram during sustained contractions with muscle fatigue
Authors: Yasushi Itoh, Kumi Akataki, Katsumi Mita, Makoto Watakabe, Kunihiko Itoh
Venue: Systems and Computers in Japan (2004)

The mechanomyogram (MMG) is a recording of mechanical oscillation that is detectable on the body surface overlying the muscle. It is considered that the MMG is produced by lateral dimensional changes in active muscle fibers, which generate pressure waves, and reflects the mechanical activity of muscle. The present study was designed to examine the MMG behavior during sustained contraction at a constant level of force up to muscle fatigue, and to determine that the MMG reflects the specific motor unit (MU) activation strategy resulting from muscle fatigue. In the experiment, isometric contractions of biceps brachii muscles at 20 and 80&percnt; of the maximal voluntary contraction (20 and 80&percnt; MVC) were selected. The recorded MMG was analyzed by the short-time Fourier transform, and the root mean squared amplitude (RMS) and mean power frequency (MPF) were calculated every 0.1 s. It was found that the RMS of the MMG at 20&percnt; MVC decreased somewhat from the onset of contractions, then gradually increased. The MPF initially increased and then remained constant. At 80&percnt; MVC, on the other hand, the RMS continued to decrease. The MPF initially increased and then decreased. These trends in the RMS and MPF seem to reflect an alteration in the MU activation strategy resulting from muscle fatigue. The MMG is considered to be one of the useful tools in monitoring muscle fatigue. &copy; 2003 Wiley Periodicals, Inc. Syst Comp Jpn, 35(1): 26&ndash;36, 2004; Published online in Wiley InterScience (). DOI 10.1002&sol;scj.10528
PLX: An Instruction Set Architecture and Testbed for Multimedia Information Processing
Authors: Ruby B. Lee, A. Murat Fiskiran
Venue: Journal of VLSI Signal Processing Systems (2005)

PLX is a concise instruction set architecture (ISA) that combines the most useful features from previous generations of multimedia instruction sets with newer ISA features for high-performance, low-cost multimedia information processing. Unlike previous multimedia instruction sets, PLX is not added onto a base processor ISA, but designed from the beginning as a standalone processor architecture optimized for media processing. Its design goals are high performance multimedia processing, general-purpose programmability to support an ever-growing range of applications, simplicity for constrained environments where low power and low cost are paramount, and scalability for higher performance in less constrained multimedia systems. Another design goal of PLX is to facilitate exploration and evaluation of novel techniques in instruction set architecture, microarchitecture, arithmetic, VLSI implementations, compiler optimizations, and parallel algorithm design for new computing paradigms.Key characteristics of PLX are a fully subword-parallel architecture with novel features like wordsize scalability from 32-bit to 128-bit words, a new definition of predication, and an innovative set of subword permutation instructions. We demonstrate the use and high performance of PLX on some frequently-used code kernels selected from image, video, and graphics processing applications: discrete cosine transform, pixel padding, clip test, and median filter. Our results show that a 64-bit PLX processor achieves significant speedups over a basic 64-bit RISC processor and over IA-32 processors with MMX and SSE multimedia extensions. Using PLX's wordsize scalability feature, PLX-128 often provides an additional 2× speedup over PLX-64 in a cost-effective way. Superscalar or VLIW (Very Long Instruction Word) PLX implementations can also add additional performance through inter-instruction, rather than intra-instruction parallelism. We also describe the PLX testbed and its software tools for architecture and related research.
On the node-scheduling approach to topology control in ad hoc networks
Authors: Budhaditya Deb, Badri Nath
Venue: Proceedings of the 6th ACM international symposium on Mobile ad hoc networking and computing (2005)

In this paper, we analyze the node scheduling approach of topology control in the context of reliable packet delivery. In node scheduling, only a minimum set of nodes needed for routing purposes (usually determined by a minimum connected dominating set, MCDS) are kept active. However, a very low density resulting from switching off nodes can adversely affect the performance of data delivery due to three factors. First, our analysis shows that at low density, the average path length increases by a factor more than previously thought. Second, protocols such as the Hop-By-Hop Broadcast (HHB) reliability scheme (which relies on high network degree for optimum performance) suffer. Third, with limited buffers at nodes, the overhead is more pronounced to the extent of making the network unstable. Using probabilistic models, we derive the relationship between network density and overhead based on the above factors and find the density conditions for minimum power consumption. We also propose a, fully distributed and message-optimal node scheduling algorithm with a constant approximation bound based on the concept of Virtual Connected Dominating Sets. The scheme can asymptotically achieve optimal density conditions while adapting to different network parameters.
Generation of Steiner tree connections in a barrier-free environment
Authors: R. J. Smith, C. V. Cao
Venue: ACM SIGDA Newsletter (1975)

We have recently developed an algorithm for the generation of Steiner trees in a barrier-free environment. The algorithm and related mathematical material appear elsewhere (1); the purpose of this note is to informally describe the concepts underlying our approach, and to demonstrate the computational feasibility of the method. Our problem model consists of a two-dimensional rectilinear grid containing nodes which must be connected by orthogonal line segments. The objective is to connect the set of nodes with a collection of lines having minimum total length. As will be demonstrated, our technique may be manually applied to problems of 25-50 points; much larger problems could be solved by utilizing computer processing. While the algorithm has not yet been proven to produce minimum length trees, we maintain that typical results are at least very nearly minimal. We hope to stimulate critical reactions to the following material by presenting it informally in this Newsletter.
Geopostors: a real-time geometry / impostor crowd rendering system
Authors: Simon Dobbyn, John Hamill, Keith O'Conor, Carol O'Sullivan
Venue: Proceedings of the 2005 symposium on Interactive 3D graphics and games (2005)

The simulation of large crowds of humans is important in many fields of computer graphics, including real-time applications such as games, as they can breathe life into otherwise static scenes and enhance believability. We present a novel hybrid rendering system for crowds that solves the classic problem of degraded quality of image-based representations at close distances by building an impostor rendering system on top of a full, geometry-based, human animation system. This enables almost imperceptible switching between the two representations based on a "pixel to texel" ratio, with minimal popping artefacts. Seamless interchanges are further facilitated by exploiting programmable graphics hardware to efficiently enhance the realism and variety of the dynamically-lit impostors, thereby also improving on existing impostor techniques. To test our system, our virtual crowds are embedded in an urban simulation system (as shown in Figure 1). The results demonstrate a system capable of rendering large realistic crowds with the visual realism of a high-resolution geometry rendering system, but at a fraction of the rendering cost.
Issues in license agreements for numerical program libraries
Authors: W. S. Brown, K. W. Fong, B. Ford
Venue: ACM SIGNUM Newsletter (1983)

During the past decade, several organizations have developed high quality libraries of mathematical subroutines that are either portable or well supported on a variety of important computers. Although some progress has been made in persuading practitioners to use these libraries, it has become apparent that the licensing contracts and negotiations are a serious barrier to their acceptance. It is essential to have a contract to define the product and service being offered and the relationship between the producer and the customer. Yet, in more than a few cases, prospective customers have found it impossible to accept restrictions that the producers consider barely adequate to protect their most fundamental interests. In other cases, the bargaining may continue for months or even years before agreement is reached.
Protecting On-Line Casinos against Fraudulent Player Drop-Out
Authors: Joaquin Garcia, Frederic Cuppens, Fabien Autrel, Jordi Castella-Roca, Joan Borrell, Guillermo Navarro, Jose A. Ortega-Ruiz
Venue: Proceedings of the International Conference on Information Technology: Coding and Computing (ITCC'05) - Volume I - Volume 01 (2005)

Some multiplayer, on-line games rely on the collaboration of all participating players. If a player's gamble is aborted, the rest of players cannot continue playing. This behavior can be used by fraudulent players to avoid paying by simply quitting the game before its completion. It is difficult to decide whether a player has left the game in a deliberated, fraudulent way, because there are many factors, both intentional and inadvertent, that can cause the abandonment. This paper presents a fraud detection system that specially fits to such scenarios. By gathering and correlating information held by multiple sources, our approach will help the on-line casino administrator to decide if a player leaving a game is actually cheating. Results of our work can be easily adapted for use against other existing on-line gambling frauds.
Towards an Industrial Strength SQL/XML Infrastructure
Authors: Muralidhar Krishnaprasad, Zhen Hua Liu, Anand Manikutty, James W. Warner, Vikas Arora
Venue: Proceedings of the 21st International Conference on Data Engineering (2005)

XML has become an attractive data processing model for applications. SQL/XML is a SQL standard that integrates XML with SQL. It introduces the XML datatype as a native SQL datatype and defines XML generation functions in the SQL/XML 2003 standard. The goal for the next version of SQL/XML is integrating XQuery with SQL by supporting XQuery embedded inside SQL functions such as the XMLQuery and XMLTable functions. Starting with the 9i database release, Oracle has supported the XML datatype and various operations on XML instances. In this paper, we present the design and implementation strategies of the SQL/XML standard in Oracle XMLDB. We explore the various critical infrastructures needed in the SQL database kernel to support an efficient native XML datatype implementation and the design approaches for efficient generation, query and update of the XML instances. Furthermore, we also illustrate extensions to SQL/XML that makes Oracle XMLDB a truly industrial strength platform for XML processing.
Specifying confidentiality
Authors: Riccardo Pucella
Venue: ACM SIGACT News (2004)

I would like to start my tenure as editor of the Logic Column by thanking Jon Riecke, who has edited this column since 1998. The Logic Column serves as a showcase of the many connections between logic and computer science. Logic has been connected with computer science since the early days of Turing. In the past few decades, logical methods have had a considerable impact. To get a sense of the range of applications, consider the 2001 NSF/CISE Workshop on The Unusual Effectiveness of Logic in Computer Science (see http: //www. cs. rice. edu/~vardi/logic/). An article derived from the workshop appeared in the Bulletin of Symbolic Logic [Halpern et al. 2001], and it is an exceedingly good read. If you get a copy of that issue of the Bulletin, make sure to also have a look at the article by Buss et al. [2001], which discusses the current state of mathematical logic.
Optimal recovery schemes in fault tolerant distributed computing
Authors: Kamilla Klonowska, H&#x00e5;kan Lennerstad, Lars Lundberg, Charlie Svahnberg
Venue: Acta Informatica (2005)

Clusters and distributed systems offer fault tolerance and high performance through load sharing. When all n computers are up and running, we would like the load to be evenly distributed among the computers. When one or more computers break down, the load on these computers must be redistributed to other computers in the system. The redistribution is determined by the recovery scheme. The recovery scheme is governed by a sequence of integers modulo n. Each sequence guarantees minimal load on the computer that has maximal load even when the most unfavorable combinations of computers go down. We calculate the best possible such recovery schemes for any number of crashed computers by an exhaustive search, where brute force testing is avoided by a mathematical reformulation of the problem and a branch-and-bound algorithm. The search nevertheless has a high complexity. Optimal sequences, and thus a corresponding optimal bound, are presented for a maximum of twenty one computers in the distributed system or cluster.
Hardness of the undirected congestion minimization problem
Authors: Matthew Andrews, Lisa Zhang
Venue: Proceedings of the thirty-seventh annual ACM symposium on Theory of computing (2005)

We show that there is no (log log M)1-ε approximation for the undirected congestion minimization problem unless NP ⊆ ZPTIME(npolylogn), where M is the size of the graph and ε is any positive constant.
A note on a secure voting system on a public network
Venue: Networks (2004)

This article shows that the procedure proposed in Chang and Wu &lpar;1997&rpar; and extended in Dini &lpar;2001&rpar; does not always produce accurate results. A modification that makes the procedure correct is suggested. &copy; 2004 Wiley Periodicals, Inc.
123 PIC Microcontroller Experiments for the Evil Genius, 1 edition
Authors: Myke Predko
Venue:  (2005)

Microchip continually updates its product line with more capable and lower cost products. They also provide excellent development tools. Few books take advantage of all the work done by Microchip. 123 PIC Microcontroller Experiments for the Evil Genius uses the best parts, and does not become dependent on one tool type or version, to accommodate the widest audience possible. Building on the success of 123 Robotics Experiments for the Evil Genius, as well as the unbelievable sales history of Programming and Customizing the PIC Microcontroller, this book will combine the format of the evil genius title with the following of the microcontroller audience for a sure-fire hit.
An e-government information architecture for regulation analysis and compliance assistance
Authors: Gloria T. Lau, Shawn Kerrigan, Kincho H. Law, Gio Wiederhold
Venue: Proceedings of the 6th international conference on Electronic commerce (2004)

The complexity and diversity of government regulations make understanding the regulations a non-trivial task. One of the issues is the existence of multiple sources of regulations and interpretive guides. In this work, we propose an information infrastructure for regulation analysis, which includes a document repository and tools for compliance assistance and similarity analysis. A regulatory repository is developed based on an XML format, and important features, such as concepts and measurements, are extracted using handcrafted rules and a text mining tool. Our framework provides compliance assistance using a reasoning tool based on First Order Predicate Calculus logic, where users are alerted of detected conflicts or otherwise compliance with the regulation. A relatedness analysis is performed by comparing the extracted features as well as structural and referential information from regulations. Examples of an electronic-rulemaking scenario and a compliance checking procedure are shown to demonstrate current capabilities of the prototype system.
Artificial color image logic
Authors: H. John Caulfield, Jian Fu, Seong-Moo Yoo
Venue: Information Sciences&mdash;Informatics and Computer Science: An International Journal (2004)

Artificial Color is simply biomimetic spectral sensing and processing to achieve spectral discrimination. Using Artificial Color means to construct image plane filters; we can then perform logic operations on those filters before applying them to scenes. Boolean and fuzzy logic can both be used. We illustrate the concept by the Boolean AND of two such masks applied to a complex scene.
Korovkin-type theorem and application
Authors: Wang Heping
Venue: Journal of Approximation Theory (2005)

Let (Ln) be a sequence of positive linear operators on C [0, 1], satisfying that (Ln(ei)) converge in C[0, 1] (not necessarily to ei) for i = 0, 1, 2, where ei(x) = xi. We prove that the conditions that (Ln) is monotonicity-preserving, convexity-preserving and variation diminishing do not suffice to insure the convergence of (Ln)(f)) for all f ∈ C[0, 1]. We obtain the Korovkin-type theorem and give quantitative results for the approximation properties of the q-Bernstein operators Bn,q as an application.
A stochastic integer programming approach to solving a synchronous optical network ring design problem
Venue: Networks (2004)

We develop stochastic integer programming techniques tailored toward solving a Synchronous Optical Network &lpar;SONET&rpar; ring design problem with uncertain demands. Our approach is based on an L-shaped algorithm, whose &lpar;integer&rpar; master program prescribes a candidate network design, and whose &lpar;continuous&rpar; subproblems relay information regarding potential shortage penalty costs to the ring design decisions. This naive implementation performs very poorly due to two major problems: &lpar;1&rpar; the weakness of the master problem relaxations, and &lpar;2&rpar; the limited information passed to the master problem by the optimality cuts. Accordingly, we enforce certain necessary conditions regarding shortage penalty contributions to the objective function within the master problem, along with a corresponding set of valid inequalities that improves the solvability of the master problem. We also show how a nonlinear reformulation of the model can be used to capture an exponential number of optimality cuts generated by the linear model. We augment these techniques with a powerful upper-bounding heuristic to further accelerate the convergence of the algorithm, and demonstrate the effectiveness of our methodologies on a test bed of randomly generated stochastic SONET instances. &copy; 2004 Wiley Periodicals, Inc. NETWORKS, Vol. 44&lpar;1&rpar;, 12&ndash;26 2004
Blind separation of convolved cyclostationary processes
Authors: J. Antoni, F. Guillet, M. El Badaoui, F. Bonnardot
Venue: Signal Processing (2005)

A non-parametric method is presented for the blind separation of convolved cyclostationary processes such as those typically observed at the output of MIMO systems driven by periodically modulated random processes. The approach is formulated in the frequency domain and is deductive in the sense that it follows the lines of optimal supervised filtering--from which the relationships to be used in the unsupervised situation are derived. This leads to an algorithm where the successive diagonalisations of some cyclic spectral density matrices give rise to unique separating filters. One important result concerns the proposal of solutions to unambiguously recover the exact source permutation at each frequency. A statistical performance analysis of the method is also conducted, with the results suggesting some strategies to increase the robustness of the separation. Examples of successful separation are finally provided on realistic convolutive mixtures, both synthetic and from the real world, where impulse responses of several thousands of coefficients are dealt with.
A definition of mobility
Authors: Alan Lelah, Karine Grein-Cochard
Venue: Proceedings of the 1st French-speaking conference on Mobility and ubiquity computing (2004)

This study proposes to give a definition of mobility that can be used as a reference in the field of telecommunications. It also presents the methodology which was employed to get to this definition.