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991.
M. Dolores Jiménez-Gamero Juan Luis Moreno-Rebollo Juan M. Muñoz-Pichardo Ana M. Muñoz-Reyes 《TEST》2005,14(2):515-542
One of the areas of Statistics in which the influence analysis has been widely studied is the multiple linear regression model.
Nevertheless, the influence diagnostics proposed in this context cannot be applied to regression in complex survey, under
randomized inference, since the i.i.d. case does not incorporate any probability weighting or population structure, such as
clustering, stratification or measures of size into the analysis.
In this paper we introduce some influence diagnostics in regression in complex survey. They are built on the conditional bias
concept (Moreno-Rebollo et al., 1999). We emphasize the similarities and differences of the proposed measures with respect
to the existing ones for the i.i.d. case.
Research partly supported by the Spanish MCYT grant BFM2001-3844 and Spanish MEC grant MTM2004-0111433. 相似文献
992.
E. Martin M. Saint-Paul A. Clément 《Journal of Materials Science: Materials in Electronics》2005,16(11-12):767-772
The elastic moduli, measured with the ultrasonic technique, of commercial silica filled epoxy resins used in the electronic circuits are reported. Measurements of velocity propagation and attenuation were carried out in large temperature and frequency ranges. Predictions of the theoretical models were compared with the experimental values. Explicit expressions of the elastic moduli were derived as functions of filler content and the properties of the matrix and the fillers. The influences of frequency and temperature on the elastic moduli and attenuation are discussed. 相似文献
993.
Rodríguez José Ignacio Jiménez José Manuel Funes Francisco Javier García de Jalón Javier 《Multibody System Dynamics》2003,10(2):177-199
In this paper a prototype of a computer program for multi-bodysimulation based on the use of CORBA, Java and XML is presented. Thisprototype makes use of a recursive dynamic formalism which outperformsmany implementations based on global formulations. The prototypepresented has been implemented using distributed Object OrientedProgramming techniques. The definition of the multi-body system is donethrough a data file defined using XML (eXtendible Markup Language). Thisprototype implements a `simulation service' on a network of computers,following a client-server scheme. This `simulation service' can operatein two different ways: offering a remote simulation on the server, orproviding a Java compiled code for local simulation on the client. Thepaper describes the practical implementation of such a service. The useof recursive functions and OOP permits the implementation of ageneral-purpose simulation code, which is compact, clear, clean,re-usable and easy to maintain. Once this Java code is compiled, it isstored in less than 125 Kbytes (including the numerical integrators).The Java programming language is used in order to assure compatibilitybetween different platforms. Finally, practical examples which make useof this approach are shown. 相似文献
994.
Reliable Computing - 相似文献
995.
Characterizing Grids: Attributes, Definitions, and Formalisms 总被引:11,自引:0,他引:11
Grid systems and technologies have evolved over nearly a decade; yet, there is still no widely accepted definition for Grids. In particular, the essential attributes that distinguish Grids from other distributed computing environments have not been articulated. Most approaches to definition adopt a static view and consider only the properties and components of, or the applications supported by, Grids. The definition proposed in this paper is based on the runtime semantics of distributed systems. Rather than attempt to simply compare static characteristics of Grids and other distributed computing environments, this paper analyzes operational differences, from the viewpoint of an application executing in both environments. Our definition is expressed formally as an Abstract State Machine that facilitates the analysis of existing Grid systems or the design of new ones with rigor and precision. This new, semantical approach proposes an alternative to the currently accepted models for determining whether or not a distributed system is a Grid. 相似文献
996.
César Muñoz Víctor Carreño Gilles Dowek Ricky Butler 《International Journal on Software Tools for Technology Transfer (STTT)》2003,4(3):371-380
Safety assessment of new air traffic management systems is a main issue for civil aviation authorities. Standard techniques
such as testing and simulation have serious limitations in new systems that are significantly more autonomous than the older
ones. In this paper, we present an innovative approach for establishing the correctness of conflict detection systems. Fundamental
to our approach is the concept of trajectory, and how we represent a continuous physical trajectory by a continuous path in
the x-y plane constrained by physical laws and operational requirements. From the model of trajectories, we extract, and formally
prove, high-level properties that can serve as a framework to analyze conflict scenarios. We use the AILS (Airborne Information
for Lateral Spacing) alerting algorithm as a case study of our approach.
Published online: 19 November 2002 相似文献
997.
Emmanuel Benoist Jean-Jacques Hébrard 《Annals of Mathematics and Artificial Intelligence》2003,37(3):251-272
The enlarged Horn formulas generalize the extended Horn formulas introduced by Chandru and Hooker (1991). Their satisfying truth assignments can be generated with polynomial delay. Unfortunately no polynomial algorithm is known for recognizing enlarged Horn formulas or extended Horn formulas. In this paper we define the class of simple enlarged Horn formulas, a subclass of the enlarged Horn formulas, that contains the simple extended Horn formulas introduced by Swaminathan and Wagner (1995). We present recognition algorithms for the simple enlarged Horn formulas and the simple extended Horn formulas whose complexity is bounded by the complexity of the arborescence-realization problem. 相似文献
998.
A set of perception experiments, using reiterant and lexicalised speech, was designed to perform a diagnostic of the relative implication of prosody in the segmentation and hierarchisation of speech. Both natural and synthetic intonation were evaluated. Then, two distance measures—correlation and root-mean-square distance on the acoustic parameters (F0, syllabic duration and intensity)—were applied to match the perception results. This objective vs. subjective comparison underlines which acoustic cues are used by listeners to judge the adequacy of prosody in performing a given function such as demarcation. Results can be summarized by a scale of the perceptual distance between two demarcation functions. This study also points out the ability of listeners to retrieve pertinent information on the basis of pure prosodic stimuli. 相似文献
999.
J. Sée P. Dollfus S. Galdin-Retailleau P. Hesto 《Journal of Computational Electronics》2003,2(2-4):449-453
This article presents a self-consistent 3D Poisson-Schrödinger calculation based on the density functional theory for silicon quantum dot under bias voltage. For various shapes and sizes of quantum dot surrounded by silicon dioxide, the energy levels and density are calculated as a function of the applied voltage and the number of stored electrons. The potential properties of such nanostructures for Coulomb blockade operation are deduced. 相似文献
1000.
Reliable Computing - 相似文献