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This article is a brief summary of the Discussion session held after the presentation of the preceding papers at the conference organized by the Industrial Carbon and Graphite Group of the Society of Chemical Industry, London, March 1984. 相似文献
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Optimal ensemble construction via meta-evolutionary ensembles 总被引:1,自引:0,他引:1
In this paper, we propose a meta-evolutionary approach to improve on the performance of individual classifiers. In the proposed system, individual classifiers evolve, competing to correctly classify test points, and are given extra rewards for getting difficult points right. Ensembles consisting of multiple classifiers also compete for member classifiers, and are rewarded based on their predictive performance. In this way we aim to build small-sized optimal ensembles rather than form large-sized ensembles of individually-optimized classifiers. Experimental results on 15 data sets suggest that our algorithms can generate ensembles that are more effective than single classifiers and traditional ensemble methods. 相似文献
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Four experiments investigated the effect of recent selective practice on the cost of switching between 2 tasks afforded by letter-digit pairs: alphabet arithmetic and shape comparison. Experiments 1 and 2 found a greater cost associated with switching to the more recently practiced task: evidence that task-set inertia contributes to switching costs. Experiment 3 found this effect to be limited to trials on which a recently trained stimulus followed another such stimulus: a result problematic for all current theories of task-set priming. Experiment 4 showed that the effect of recent practice was eliminated by active preparation for a task switch: It appears that endogenous task-set preparation reduces the effects of task-set inertia. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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This report describes the results of a survey completed in December 1988 on the production and employment of PhDs and faculty in PhD-granting computer science/engineering departments during the 1987-8 academic year. All 127 computer science (CS) departments (115 US and 12 Canadian) participated. In addition, 34 departments offering the PhD in computer engineering (CE) were included. Throughout the report. CE statistics are reported separately so that comparisons with previous years can be made for CS. The intent is to merge all statistics for CS and CE after several years 相似文献
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David Haussler Michael Kearns Nick LittlestoneManfred K. Warmuth 《Information and Computation》1991,95(2)
In this paper we consider several variants of Valiant's learnability model that have appeared in the literature. We give conditions under which these models are equivalent in terms of the polynomially learnable concept classes they define. These equivalences allow comparisons of most of the existing theorems in Valiant-style learnability and show that several simplifying assumptions on polynomial learning algorithms can be made without loss of generality. We also give a useful reduction of learning problems to the problem of finding consistent hypotheses, and give comparisons and equivalences between Valiant's model and the prediction learning models of Haussler, Littlestone, and Warmuth (in “29th Annual IEEE Symposium on Foundations of Computer Science,” 1988). 相似文献
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The cytosolic chaperonin containing TCP-1 (CCT) is known to keep fold cytoskeletal proteins and is involved in the proper organization of the cytoskeleton. These studies are based on the assumption that growth responses linked to structural rearrangement of the plant cytoskeleton include the action of CCT and the need for newly synthesized tubulin. The presence of the alpha- and epsilon-subunits of CCT was investigated in soluble fractions of protein extracts from maize mesocotyls and coleoptiles at distinct growth stages. The CCT-subunits, tubulins and actin decreased in the coleoptile in response to far-red light. In addition, independent from light treatment, the amount of CCT epsilon abundance declined with age in coleoptiles and mesocotyls between 2 and 4.5 days after sowing. In contrast to CCT epsilon, no significant light regulation of CCT alpha was found in the mesocotyl. In two day old, light-grown rapidly elongating coleoptiles part of the CCT alpha subunit and the bulk of actin and tubulin was found shifted into fractions of high molecular weight complexes when compared to slowly elongating, dark grown coleoptiles. In 4.5 day old, etiolated and elongating coleoptiles, part of both CCT-subunits and cytoskeleton proteins were found in fractions of high molecular weight. A complete disappearance of these polypeptides was observed in old far-red irradiated growth-arrested coleoptiles. CCT epsilon was found to be colocalized to microtubular structures and to the nucleus. We conclude from our data that abundance of CCT-subunits in soluble extracts is dependent on age and light treatment, but independent from the growth stage of mesocotyl and coleoptile. 相似文献
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Theodore Karoubalis Kostas Adaos George Ph. Alexiou Nick Kanopoulos 《International Journal of Circuit Theory and Applications》1995,23(6):587-598
This paper describes an efficient technique for the design of fault-secure VLSI circuits based on differential cascode voltage switch (DCVS) logic. We propose a new synthesis method for constructing DCVS circuits with a near-optimal transistor count based on binary decision diagrams (BDDs). the time and memory resources required are very low, making the technique practical even for PC-based synthesis tools. This method is the basis for a CAD tool that allows automatic synthesis of fault-secure circuits based on the DCVS technology. We finally present an improved design and implementation of a 2's complement serial/parallel multiplier as an application of the proposed technique and algorithm. 相似文献