ppxscal/embedding_network huggingface dataset:
A finite element formulation for no-tension materials in finite deformations
Authors: M. Cuomo, M. Fagone
Venue: Proceedings of the sixth conference on Computational structures technology (2002)

In the paper it is presented a non linear finite element formulation for unilateral materials in the field of finite deformations. This kind of materials are not able to sustain any compressive (resp. tensile) stress and represent a special case of anelastic materials, whose irreversible deformations is ruled by a potential. Particularly it has been developed a constitutive model for no tension materials on the basis of a multiplicative split of the gradient of deformation tensor in an elastic and anelastic part introducing an intermediate (stress free) configuration and assuming that no dissipations occurs in the anelastic process. It is proved that the symmetric part of the gradient of velocity tensor can be additively decomposed in an elastic and an anelastic component that yield the elastic and anelastic mechanical power provided that a properly defined covariant velocity of deformation tensor is used.The model is implemented in a standard isoparametric finite elements model using a linearisation of the time derivative of the right Cauchy-Green tensor, of the velocity of deformation tensors and of the Lie derivative of the Kirchhoff stress tensor. Explicit expressions for the components of the material and geometric tangent stiffness matrices and for the equivalent internal nodal forces are furnished.
Non-Commutative Arithmetic Circuits: Depth Reduction and Size Lower Bounds
Authors: Eric Allender, Jia Jiao, Meena Mahajan, V. Vinay
Venue:  (1996)

We investigate the phenomenon of depth-reduction in commutative and non-commutative arithmetic circuits. We prove that in the commutative setting, uniform semi-unbounded arithmetic circuits of logarithmic depth are as powerful as uniform arithmetic circuits of polynomial degree; earlier proofs did not work in the uniform setting. This also provides a unified proof of the circuit characterizations of LOGCFL and #LOGCFL. We show that AC^1 has no more power than arithmetic circuits of polynomial size and degree n^{O(log log n)} (improving the trivial bound of n^{O(log n)}). Connections are drawn between TC^1 and arithmetic circuits of polynomial size and degree. Then we consider non-commutative computation, and show that some depth reduction is possible over the algebra (Sigma^*, max, concat), thus establishing that OptLOGCFL is in AC^1. This is the first depth-reduction result for arithmetic circuits over a noncommutative semiring, and it complements the lower bounds of Kosaraju and Nisan showing that depth reduction cannot be done in the general noncommutative setting. We define new notions called ``short-left-paths'''' and ``short-right-paths'''' and we show that these notions provide a characterization of the classes of arithmetic circuits for which optimal depth-reduction is possible. This class also can be characterized using the AuxPDA model. Finally, we characterize the languages generated by efficient circuits over the (union, concat) semiring in terms of simple one-way machines, and we investigate and extend earlier lower bounds on non-commutative circuits.
A Framework to Protect Mobile Agents by Using Reference States
Authors: Fritz Hohl
Venue: Proceedings of the The 20th International Conference on Distributed Computing Systems ( ICDCS 2000) (2000)

To protect mobile agents from attacks by their execution environments, or hosts, one class of protection mechanisms uses reference states to detect modification attacks. Reference states are agent states that have been produced by non-attacking, or reference hosts.This paper examines this class of mechanisms and presents the bandwidth of the achieved protection. First, the notion of reference states is introduced. This notion allows to define a protection scheme that can be used to realize a whole class of mechanisms to protect mobile agents. To do so, after an initial analysis of already existing approaches, the abstract features of these approaches are extracted. A discussion examines the strengths and weaknesses of the general protection scheme, and a framework is presented that allows an agent programmer to choose an appropriate protection level using this scheme. An example illustrates the usage of the framework and its overhead.
Generating test sequences from a set of MSCs
Authors: Nam Hee Lee, Sung Deok Cha
Venue: Computer Networks: The International Journal of Computer and Telecommunications Networking (2003)

We propose an approach to generate test cases from a set of Message Sequence Charts (MSCs) by constructing a semantically equivalent finite state machine for testing reactive and embedded software. Test cases are expressed as a sequence of messages to be exchanged among various system entities. We use scenario activation conditions and state assignments to generate only the feasible states and transitions. This paper uses complex digital TV software to illustrate how test cases are automatically generated.
Induced magnetic field computations using a boundary integral formulation
Authors: S. Balac, G. Caloz
Venue: Applied Numerical Mathematics (2002)

A method to compute the magnetic field induced by a metallic body embedded in a uniform external field is presented. It is based on boundary integral representation formulae for the magnetic induction . A computational procedure is proposed which consists of using analytic expressions to compute the integral over the flat panels of the boundary and a piecewise quadratic interpolation of the surface for the curved panels. Superconvergence occurs in the latter case. The method supplies both high accuracy and low computation time, requirements that are not fulfilled when using standard numerical methods.
Interval p-Neighborhood Graphs
Authors: J. R Lundgren, Patricia A. McKenna, Sarah K. Merz, Craig W. Rasmussen
Venue:  (1995)

The (p)-neighborhood graph of a graph G, denoted Np(G), is defined on the same vertex set as G, with [x,y] E(N_2(G)) if and only if N(x) \cap N(y) <= p in G, where N(v) is the open neighborhood of vertex v. The [p]-neighborhood graph of G, Np[G], is defined similarly, using closed neighborhoods rather than open ones. If G is the underlying graph of a symmetric digraph D, then the p-neighborhood graph of G is the p-competition graph of D. The case p=1 has been stuidied by several authors. We consider the general case, asking, "which graphs have interval p-neighborhood graphs", and give specific results for the case p=2.
Implementation and Testing of the Boolean Vector Machine
Authors: A R Wagner, John Poulton
Venue:  (1985)

This paper describes our experiences in implementing and testing two versions of the Boolean Vector Machine [1], a fairly general-purpose high-performance array computer. The narrative outlines some successes--implementation of a test environment that allows full-speed functional testing and diagnosis of our custom chips, including on-chip probing--and one notable failure-- a design flaw that was not readily predictable by simulation. Our experiences suggest that ``analog'''' simulation should be used very carefully in predicting performance (and must still be augmented by the designer''s experience and intuition) and that effort spent in constructing a powerful test facility is well spent.
On the complexity of polynomial matrix computations
Authors: Pascal Giorgi, Claude-Pierre Jeannerod, Gilles Villard
Venue: Proceedings of the 2003 international symposium on Symbolic and algebraic computation (2003)

We study the link between the complexity of polynomial matrix multiplication and the complexity of solving other basic linear algebra problems on polynomial matrices. By polynomial matrices we mean ntimes n matrices in K[x] of degree bounded by d, with K a commutative field. Under the straight-line program model we show that multiplication is reducible to the problem of computing the coefficient of degree d of the determinant. Conversely, we propose algorithms for minimal approximant computation and column reduction that are based on polynomial matrix multiplication; for the determinant, the straight-line program we give also relies on matrix product over K[x] and provides an alternative to the determinant algorithm of [16, 17]. We further show that all these problems can be solved in particular in O (ω) operations in K. Here the "soft O" notation O indicates some missing log (nd) factors and ω is the exponent of matrix multiplication over K.
Robust Set Operations on Polyhedral Solids
Authors: Christoph M. Hoffmann, John E. Hopcroft, Michael S. Karasick
Venue:  (1987)

We describe an algorithm for performing regularized set operations on polyhedral solids. Robustness of this algorithm is achieved by adding symbolic reasoning as a supplemental step that compensates for possible numerical uncertainty. The algorithm has been implemented, and our experience with the implementation is discussed.
Tellegen's principle into practice
Authors: A. Bostan, G. Lecerf É. Schost
Venue: Proceedings of the 2003 international symposium on Symbolic and algebraic computation (2003)

The transposition principle, also called Tellegen's principle, is a set of transformation rules for linear programs. Yet, though well known, it is not used systematically, and few practical implementations rely on it. In this article, we propose explicit transposed versions of polynomial multiplication and division but also new faster algorithms for multipoint evaluation, interpolation and their transposes. We report on their implementation in Shoup's NTL C++ library.
When query expansion fails
Authors: Bodo Billerbeck, Justin Zobel
Venue: Proceedings of the 26th annual international ACM SIGIR conference on Research and development in informaion retrieval (2003)

The effectiveness of queries in information retrieval can be improved through query expansion. This technique automatically introduces additional query terms that are statistically likely to match documents on the intended topic. However, query expansion techniques rely on fixed parameters. Our investigation of the effect of varying these parameters shows that the strategy of using fixed values is questionable.
Relating usability to design practice
Authors: John Knight, Marie Jefsioutine
Venue: Proceedings of the 1st European UPA conference on European usability professionals association conference - Volume 3 (2002)

Discusses the obstacles that prevent digital media designers from adopting usability methods and tensions between the usability and design communities, Explores how to enhance communication between the two groups.
Balinda C++: Runtime Support for Concurrent Object-Oriented Language
Authors: H. C. Wang, C. K. Yuen, M. D. Feng
Venue: Proceedings of the 1999 International Symposium on Parallel Architectures, Algorithms and Networks (1999)

Runtime systems are critical to the implementation of concurrent object-oriented programming languages. This paper describes a concurrent object-oriented programming language -- Balinda C++, running on a distributed memory system and its runtime implementation. The runtime system is built on the top of the Nexus communication library. The tuplespace is the key of Balinda C++. A distributed tuplespace model is presented to improve data locality. Some experiments have been done to verify our model. The results indicate that our model is effective to improve system performance.
Polynomial Bounds for VC Dimension of Sigmoidal and General PfaffianNeural Networks
Authors: Marek Karpinski, Angus Macintyre
Venue:  (1996)

We introduce a new method for proving explicit upper bounds on the VC Dimension of general functional basis networks, and prove as an application, for the first time, that the VC Dimension of analog neural networks with the sigmoidal activation function $\sigma(y) = 1/1+e^{-y}$ is bounded by a quadratic polynomial $O((lm)^2)$ in both the number $l$ of programmable parameters, and the number $m$ of nodes. The proof method of this paper generalizes to much wider class of Pfaffian activation functions and formulas, and gives also for the first time polynomial bounds on their VC Dimension. We present also some other applications of our method.
Flexible multicast protocol
Authors: A. Siafa
Venue: Proceedings of the 6th International Conference on Computer Communications and Networks (1997)

This paper presents FMP, a flexible multicast protocol based on the SRM algorithm in order to guarantee a reliable multipoint communication support. FMP is intended to strengthen the SRM repair/request policies, as well as to optimise the recovery treatments in case of failure occurence. Moreover, FMP is designed to meet the variety of needs of multicast applications by providing a mean to select the suitable service at the application level. Estelle is used to specify one of the FMP's functionalities, i.e. the reliable multicast.
On the Use of Genetic Algorithms in Database Client Clustering
Authors: Je-Ho Park, Vinay Kanitar, Alex Delis
Venue: Proceedings of the 11th IEEE International Conference on Tools with Artificial Intelligence (1999)

In conventional two-tier client-server databases, clients access and modify shared data resident in a common server. As the number of clients increases, the centralized database server can become a performance bottleneck. In order to overcome this scalability problem, a three-tier client-server configuration has been proposed that features the partitioning of clients into logical clusters. Here, the objective is to maximize the data sharing among the clients in each cluster. In this paper, we propose a genetic algorithm to create such client clusters and evaluate two different techniques for generating the initial solution populations. We compare the performance of the two-tier and three-tier configurations with respect to the transaction turnaround times and object response times. Our experimental results indicate that the clustered architecture can offer improved performance over its two-tier counterpart.
A new algorithm for multiresolution isosurface extraction
Authors: Xiaomei Wang, Dong Feng, Jiaoying Shi
Venue: Proceedings of the IEEE Conference on Information Visualisation (1997)

We put forward a marching cube algorithm based on the extraction and expression of multiresolution isosurfaces. It can solve the problem of too much and too meticulous triangular meshes on a traditional marching cube algorithm with single resolution. At the same time, under the users' requests, it can apply various precision to different regions of the object to get a compromise between rendering time and image precision. Our algorithm firstly, begins with low resolution images, and gradually extracts high precision isosurfaces from high resolution ones to achieve multiresolution rendering; finally, it establishes the corresponding relationship between different resolution isosurfaces and images. Specifically, the algorithms use a new 3D image encoding method: recursive subdivision wavelet encoding which is more suitable for extracting multiresolution isosurfaces.
A Theory of Term Importance in Automatic Text Analysis
Authors: Gerard Salton, C. S. Yang, C. T. Yu
Venue:  (1974)

Most existing automatic content analysis and indexing techniques are based on word frequency characteristics applied largely in an ad hoc manner. Contradictory requirements arise in this connection, in that terms exhibiting high occurence frequencies in individual documents are often useful for high recall performance (to retrieve many relevant items), whereas terms with low frequency in the whole collection are useful for high precision (to reject nonrelevant items).
Assessment of the OpenAccess Standard: Insights on the new EDA Industry Standard from Hewlett-Packard, a Beta Partner and Contributing Developer
Authors: Terry Blanchard
Venue: Proceedings of the 4th International Symposium on Quality Electronic Design (2003)

The rapidly increasing complexity and qualityrequirements of integrated circuit design can only beaddressed effectively by a design system architecture thatsupports very efficient, high-quality sharing of IC designdata. The OpenAccess Coalition is delivering an industrystandard Application Programming Interface (API) andInformation Model (IM) that provides access to a shareddatabase as an essential infrastructure component formodern IC design systems. The OpenAccess Standard IM1and API, along with its reference implementation will bereleased to the industry early in 2003. Hewlett-Packardhas participated in OpenAccess from the outset and mostrecently as a Beta evaluation partner for this OA industryrelease. HP has discovered many insights about theOpenAccess standardization process as well asspecifically about the IM/API Standard and its referenceimplementation, which will be summarized herein, andexplained in more detail during the presentation at theISQED Conference.
Weighted fuzzy averages in fuzzy environment: part I. Insufficient expert data and fuzzy averages
Authors: G. Sirbiladze, A. Sikharulidze
Venue: International Journal of Uncertainty, Fuzziness and Knowledge-Based Systems (2003)

Three new versions of the most typical value (MTV)1,2 of the population (generalized weighted averages) are introduced. The first version, WFEVg, is a generalization of the weighted fuzzy expected value (WFEV)3 for any fuzzy measure g on a finite set and it coincides with the WFEV when a sampling probability distribution is used. The second and the third version are respectively the weighted fuzzy expected intervals WFEI and WFEIg which are generalizations of the WFEV, namely, MTVs of the population for a sampling distribution and for any fuzzy measure g on a finite set, respectively, when the fuzzy expected interval (FEI)4 exists but the fuzzy expected value (FEV)4 does not. The construction process is based on the Friedman-Schneider-Kandel (FSK)3 principle and results in the new MTVs called the WFEI and the WFEIg when the combinatorial interval extension of a function5 is used.
Complete Orthogonal Decomposition for Weighted Least Squares
Authors: Patricia Hough, Stephen Vavasis
Venue:  (1995)

Consider a full-rank weighted least-squares problem in which the weight matrix is highly ill-conditioned. Because of the ill-conditioning, standard methods for solving least-squares problems, QR factorization and the nullspace method for example, break down. G. W. Stewart established a norm bound for such a system of equations, indicating that it may be possible to find an algorithm that gives an accurate solution. S. A. Vavasis proposed a new definition of stability that is based on this result. He also proposed the NSH algorithm for solving this least-squares problem and showed that it satisfies the new definition of stability. This paper describes a complete orthogonal decomposition algorithm to solve this problem and shows that it is also stable. This new algorithm is simpler and more efficient than the NSH method.
Performance and Reliability Modeling Using Markov Regenerative Stochastic Petri Nets
Authors: Hoon Choi
Venue:  (1993)

Stochastic timed Petri nets are recognized as useful modeling tools for analyzing the performance and reliability of systems. However, one of the problems in using these Petri nets is that the distributions of event times are usually restricted in order to solve the model analytically and numerically rather than by simulation. We introduce a new class of Petri nets called {\em Markov Regenerative Stochastic Petri Nets} (MRSPNs) to relieve this restriction. The MRSPNs are stochastic timed Petri nets in which the underlying stochastic processes are Markov regenerative processes. The MRSPNs allow generally distributed timed transitions as well as immediate transitions and exponentially distributed timed transitions. With a condition that at most one generally distributed timed transition is enabled in each marking, an MRSPN can be solved analytically. We provide a transient (time-dependent) analysis method and a steady state analysis method for this new class of Petri nets. As a specific example of general distributions, we provide the equations for an MRSPN in which the general distributions are restricted to be deterministic. This class of MRSPNs is called DSPN. We investigate the sensitivity of DSPN models by studying the variation of output performance with respect to changes of a system parameter. We show an algorithm for computing the sensitivity functions in terms of steady state probabilities of the DSPN. Another problem with using stochastic timed Petri nets is that the size of state space of the underlying stochastic process tends to be large. To overcome this largeness problem, we propose two approximation models. We approximate client-server systems with the folding method and polling systems with the fixed point iteration method. Several performance measures such as the mean cycle time, the mean response time and throughputs are obtained. As a study of reliability analysis, we introduce a new type of the mean time to failure (MTTF) named {\em conditional MTTF} and provide its computational method in a continuous-time Markov chain model of a system.
Bayesian Field Theory: Nonparametric Approaches to Density Estimation
Authors: Jörg C. Lemm
Venue: Proceedings of the IEEE-INNS-ENNS International Joint Conference on Neural Networks (IJCNN'00)-Volume 2 - Volume 2 (2000)

Nonparametric approaches to density estimation are discussed from a Bayesian perspective. Being in general non-Gaussian the resulting models have to be solved by discretization. A numerical example shows that this can be computationally feasible for low-dimensional problems.
Key Message Algorithm: A Communication Optimization Algorithm in Cluster-Based Parallel Computing
Authors: Ming Zhu, Wentong Cai, Bu-Sung Lee
Venue: Proceedings of the 1st IEEE Computer Society International Workshop on Cluster Computing (1999)

Parallel computing using Network of Workstations (NOWs) has become very popular recently. However, the execution of parallel applications on such systems has been hampered by the high communication overhead. To reduce the communication overhead and to speedup the execution of parallel applications on NOWs, this paper proposes a Key Message approach that minimizes the cost of message-passing in a parallel application by prioritizing communications in the underlying shared communication network. In this paper, we first describe the queuing network model on which our approach is based, then introduce the algorithm that identifies the messages to be prioritized in a parallel application, and finally discuss the results obtained. Our preliminary analysis of the algorithm on randomly generated task graphs shows improvement over the system without using the prioritization scheme.
A Linear Time Algorithm for the Generalized Consecutive Retrieval Problem
Authors: Paul F. Dietz, Merrick Furst, John E. Hopcroft
Venue:  (1979)

THe Generalized Consecutive Retrieval Problem (GCRP) is to find a directed tree on $n$ records in which each of $k$ subsets forms a directed path. The problem arises in organizing information for efficient retrieval. A linear time algorithm for the GCRP is given. Further generalization leads to problems that are complete for NP.