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1.
Although greedy algorithms possess high efficiency, they often receive suboptimal solutions of the ensemble pruning problem, since their exploration areas are limited in large extent. And another marked defect of almost all the currently existing ensemble pruning algorithms, including greedy ones, consists in: they simply abandon all of the classifiers which fail in the competition of ensemble selection, causing a considerable waste of useful resources and information. Inspired by these observations, an interesting greedy Reverse Reduce-Error (RRE) pruning algorithm incorporated with the operation of subtraction is proposed in this work. The RRE algorithm makes the best of the defeated candidate networks in a way that, the Worst Single Model (WSM) is chosen, and then, its votes are subtracted from the votes made by those selected components within the pruned ensemble. The reason is because, for most cases, the WSM might make mistakes in its estimation for the test samples. And, different from the classical RE, the near-optimal solution is produced based on the pruned error of all the available sequential subensembles. Besides, the backfitting step of RE algorithm is replaced with the selection step of a WSM in RRE. Moreover, the problem of ties might be solved more naturally with RRE. Finally, soft voting approach is employed in the testing to RRE algorithm. The performances of RE and RRE algorithms, and two baseline methods, i.e., the method which selects the Best Single Model (BSM) in the initial ensemble, and the method which retains all member networks of the initial ensemble (ALL), are evaluated on seven benchmark classification tasks under different initial ensemble setups. The results of the empirical investigation show the superiority of RRE over the other three ensemble pruning algorithms. 相似文献
2.
介绍了文档数据库Lotus Domino/Notes的特点.对其文档处理的核心,即Notes文档的ID构成机制作了系统剖析.并在此基础上分析了如何在文档复制中运用ID的不同组件以及如何运用API程序访问文档ID等。 相似文献
3.
光电设备电子机柜布线工艺研究 总被引:5,自引:0,他引:5
作为信号和电能载体的导线,同时也是噪声的载体和外来噪声侵入设备的媒体。描述了噪声通过导线侵入设备内部的方式,通过降低噪声的途径确定了机柜布线的原则,介绍了布线的要求和方法,最后提出了用布线槽布线的建议。 相似文献
4.
This paper presents the main current theoretical issues in Information Retrieval. The principles of conceptual modelling, as they have emerged in the database area, are presented and their application to document modelling in order to enhance document retrieval is discussed. Finally, the main features of the MULTOS project are presented and critically reviewed confronting them with the requirements which have been identified during the general discussion on document conceptual modelling for information retrieval. 相似文献
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Andrzej Ciepielewski 《International journal of parallel programming》1991,20(6):421-451
Implementation of or-parallel Prolog systems offers a number of interesting scheduling problems. The main issues are the interaction between memory models and scheduling, ordering of multiple solutions, and scheduling of speculative work. The problems occur partly because of the design choices (e.g. the choice of a memory model), and partly because of the desire to maintain observational equivalence between parallel and sequential implementations of Prolog, while achieving high efficiency. In the first part of this paper a common framework for discussing scheduling in or-parallel systems is introduced, and also a collection of issues that must be addressed in such systems is presented. In the second part of the paper we survey a number of solutions to these problems comparing their efficiency whenever possible. We close the survey with a short discussion of open problems.Current association: Carlstedt Elektronik AB 相似文献
8.
Structured document storage and refined declarative and navigational access mechanisms in HyperStorM 总被引:2,自引:0,他引:2
Klemens Böhm Karl Aberer Erich J. Neuhold Xiaoya Yang 《The VLDB Journal The International Journal on Very Large Data Bases》1997,6(4):296-311
The combination of SGML and database technology allows to refine both declarative and navigational access mechanisms for
structured document collection: with regard to declarative access, the user can formulate complex information needs without
knowing a query language, the respective document type definition (DTD) or the underlying modelling. Navigational access is
eased by hyperlink-rendition mechanisms going beyond plain link-integrity checking. With our approach, the database-internal
representation of documents is configurable. It allows for an efficient implementation of operations, because DTD knowledge
is not needed for document structure recognition. We show how the number of method invocations and the cost of parsing can
be significantly reduced.
Edited by Y.C. Tay. Received April 22, 1996 / Accepted March 16, 1997 相似文献
9.
The application of irradiation in silicon crystal is introduced.The defects caused by irradiation are reviewed and some major ways of studying defects in irradiated silicon are summarized.Furthermore the problems in the investigation of irradiated silicon are discussed as well as its properties. 相似文献
10.
Wolfgang Appelt 《Computer Standards & Interfaces》1988,7(4):377-385
The Office Document Architecture (ODA) is an International Standard which is developed by TC 97/sc 18 of the International Organization for Standardization (ISO) in close collaboration with CCITT's Study Group VIII and with ECMA. This paper describes the current state of a formal specification of the ODA document structures by mathematical means and its use for conformance specification and conformance testing. 相似文献