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51.
Ph. Delsarte Y. Genin Y. Kamp 《International Journal of Circuit Theory and Applications》1979,7(2):257-266
The aim of this paper is a two-variable extension of some classical results by Carathéodory and Schur, characterizing the classes of positive and bounded analytic functions. It is shown how these functions can be approximated by a convergent sequence of polynomials of the same class. The particular case where bounded two-variable functions reduce to rational inner functions is described. As an application, the integral representation of positive functions is used to generate the complete family of two-variable reactances of the first degree. 相似文献
52.
53.
Analyzed criteria of performance and adaptation of Peace Corps volunteers in Tonga (N = 52) who had received high overall evaluation, moderate to marginal overall evaluation, or who had terminated early. Ss were rated independently by 3 present or past staff members on a 24-item field-rating form derived from interviews. The items were found to meet criteria of internal consistency, interjudge agreement, and discrimination of the 3 subgroups. Both discriminant and factor analyses revealed that basic character traits were the single most important class of variables, followed by 3 factors labeled General Technical Competence, Cultural Interaction, and Interpersonal Relations. The necessity for pooled judgments by competent people and for basic research to justify professional psychological services in the field is discussed, and implications for the systematic evaluation of selection and training in governmental agencies are examined. (21 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
54.
J. Daniel Polston Jesse B. Hoagg 《International Journal of Adaptive Control and Signal Processing》2015,29(5):581-602
We present a decentralized model reference adaptive control method, where each local controller uses full‐state feedback from the local subsystem. The controller is strictly decentralized, meaning that no information (including reference‐model trajectories) is shared between local controllers. This decentralized controller achieves stabilization, command following, and disturbance rejection provided that the reference‐model commands and the disturbances are sinusoidal with known spectrum. The controller is effective for multi‐input subsystems with arbitrarily large subsystem interconnections. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
55.
Among the different components present in spent nuclear fuel, long-lived trivalent actinides are particularly difficult to separate from the shorter-lived lanthanide fission products due to their similar chemical properties. Selective extraction of americium from acidic solution (up to 2M HNO3) containing tenth molar quantities of lanthanides has been achieved using neutral pyridine-based ligands dissolved in polar diluents. Nitrogen-based Bis Triazinyl Pyridine (BTP) ligands are desirable for both their excellent An/Ln selectivity and incinerability. Results pertaining to ligand solubility, kinetics, hydrolytic stability, and extraction performance in various nitric acid environments are presented. 相似文献
56.
57.
Centralized heavyweight collectors have been used to collect text-based web objects for building search engines. However,
these collectors do not meet the need of collecting big web objects such as images and videos. We propose a lightweight mobile
on-call object collector for the world wide web. Using this approach, we can deploy a collector easily on the site being indexed.
We present a prototype system consisting of mobile Java collectors and search engines for collecting HTML/image objects. We
provide analysis to find a lower bound in terms of total data transfer time required. This idealized scenario is complemented
with another model based on implementation of the HTTP over TCP. The lower bound and the upper bound of the gains accrued
are then validated using experiments.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
58.
Gomes Heitor Murilo Read Jesse Bifet Albert Durrant Robert J. 《Knowledge and Information Systems》2021,63(7):1597-1625
Knowledge and Information Systems - Ensemble methods represent an effective way to solve supervised learning problems. Such methods are prevalent for learning from evolving data streams. One of the... 相似文献
59.
Heyninck Jesse Kern-Isberner Gabriele Thimm Matthias Skiba Kenneth 《Annals of Mathematics and Artificial Intelligence》2021,89(10-11):1075-1099
Annals of Mathematics and Artificial Intelligence - The exact relationship between formal argumentation and nonmonotonic logics is a research topic that keeps on eluding researchers despite recent... 相似文献
60.
Jesse Kamp Anup Rao Salil Vadhan David Zuckerman 《Journal of Computer and System Sciences》2011,77(1):191-220
We give polynomial-time, deterministic randomness extractors for sources generated in small space, where we model space s sources on as sources generated by width branching programs. Specifically, there is a constant such that for any , our algorithm extracts bits that are exponentially close to uniform (in variation distance) from space s sources with min-entropy δn, where . Previously, nothing was known for , even for space 0. Our results are obtained by a reduction to the class of total-entropy independent sources. This model generalizes both the well-studied models of independent sources and symbol-fixing sources. These sources consist of a set of r independent smaller sources over , where the total min-entropy over all the smaller sources is k. We give deterministic extractors for such sources when k is as small as , for small enough ?. 相似文献