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51.
Terry WindeattAuthor Vitae 《Pattern recognition》2003,36(12):2743-2756
Various measures, such as Margin and Bias/Variance, have been proposed with the aim of gaining a better understanding of why Multiple Classifier Systems (MCS) perform as well as they do. While these measures provide different perspectives for MCS analysis, it is not clear how to use them for MCS design. In this paper a different measure based on a spectral representation is proposed for two-class problems. It incorporates terms representing positive and negative correlation of pairs of training patterns with respect to class labels. Experiments employing MLP base classifiers, in which parameters are fixed but systematically varied, demonstrate the sensitivity of the proposed measure to base classifier complexity. 相似文献
52.
一个表示和运用非功能性需求的框架 总被引:1,自引:0,他引:1
本文分析了一个软件开发进程中表示和运用非功能性需求的综合框架,该框架的目的是开发一套技术以调整软件开发进程中的设计决策,从而强调了依据非功能需求,探索合理化的软件开发进程。 相似文献
53.
岩心PI值试验研究及应用 总被引:5,自引:0,他引:5
主要论述了在多功能采油化学用剂评价仪上进行的岩心PI值试验的步骤,现象及结论。重点考察了岩心PI值与渗透率、流量及注入截面面积的关系;平行管岩心复合PI值和其中单管岩心PI值的关系。 相似文献
54.
By incorporating digraph models, fault trees and fuzzy inference mechanisms in a unified framework, a novel approach for fault diagnosis is developed in this work. To relieve the on-line computation load, the fault origins considered in diagnosis are limited to the basic events in the cut sets of a given fault tree. The symptom occurrence order associated with each root cause is derived from system digraph with the qualitative simulation techniques. The implied candidate patterns are enumerated according to two proposed theorems and then encoded in the inference system with IF-THEN rules. The simulation results show that the proposed approach is not only feasible but also capable of identifying the most likely cause(s) of a hazardous event at the earliest possible time. 相似文献
55.
Decision support systems depend on a variety of knowledge management techniques. These range from data base management, programming, and spreadsheet analysis to rule set management and automated inference. One valuable knowledge management technique that has yet to find its way into the repertoire of decision support system developers is general-purpose demon management. This article identifies and explores the major issues pertaining to the integration of demon representation and processing into a knowledge management environment. These serve as a basis for design and implementation of more flexible and powerful environments for decision support. 相似文献
56.
57.
利用FTA方法对脱液机的各种故障进行系统分析,建立了脱液机的故障树,并对故障树进行定性分析.找出了影响脱液机可靠性的主要因素,提出了提高脱液机可靠性的相应措施. 相似文献
58.
充分灌与调亏灌溉条件下桃树滴灌的耗水量研究 总被引:19,自引:0,他引:19
本文研究了充分灌与调亏灌溉条件下桃树滴灌的耗水量。在田间设置有两个处理,其一是在整个生育期以蒸发量的80%进行充分灌溉;其二是在果实生长缓慢期以蒸发量的20%进行亏缺灌溉,而在其它季节以蒸发量的80%进行充分灌溉。利用石膏块土壤水分传感器和中子仪分别测量了根区土壤水势和土壤含水量的变化,并实测了果实生长量、枝条生长量和产量。利用水量平衡法得出了在上述两种滴灌条件下桃树不同生育期的日均耗水量与蒸发皿系数。与充分灌比较,调亏灌溉对产量没有影响,灌水量减少了32%,并有效抑制了枝条生长。 相似文献
59.
Peter P. Mykytyn Jr. 《AI & Society》1989,3(2):133-141
Expert systems have been concerned with applications dealing with medical diagnosis, mineral exploration, and computer configuration, with some efforts relatively successful in achieving results at least as good as human experts. Today, much is being written about these systems and managerial decision-making activities in organizations and the positive impact that they can have in these situations. However, it appears that expert systems could become somewhat of a panacea for some organizational ailments as research, development, and marketing of them continues at a fast pace. What may be forgotten in this technological thrust is the individual decision maker and his/her unique style of decision making which could affect acceptance and use of these systems. Another important consideration is the attitude people have toward computers and computer systems, which along with decision-making styles could certainly affect expert system effectiveness and ultimate success in organizations. This paper provides a discussion of potential problems that could occur regarding individual decision making and attitudes and their relationships to these systems. 相似文献
60.
Datum-Hierarchy Tree Method for Tolerance Analysis of Plating and Heat Treatment Operations 总被引:1,自引:1,他引:0
G.A. Britton 《The International Journal of Advanced Manufacturing Technology》2002,19(6):442-447
This paper presents a new method for the tolerance analysis of plating and heat treatment operations. It is suitable for both
manual and computerised tolerance analysis. The new method uses a datum-hierarchy tree to identify tolerance stacks and a
stock removal set matrix to calculate the positions of surfaces created during the manufacturing sequence. A tolerance chart
is used to associate stock removal sets with the geometry of the workpiece, to show the manufacturing sequence, and to record
the operation data and the tolerance analysis results. Plating and heat treatment operations are represented as edges in the
tree, so that for each operation (edge) the input and output nodes represent consecutive surfaces in a stock removal set.
Rules are given for calculating the tolerance stackups and the positions of the surfaces in the stock removal sets. The method
is illustrated with an example. 相似文献