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111.
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
112.
Coupling GIS with Hydrologic and Hydraulic Flood Modelling 总被引:6,自引:1,他引:5
Nunes Correia Francisco Castro Rego Filipe Da Grača Saraiva Maria Ramos Isabel 《Water Resources Management》1998,12(3):229-249
Geographic Information Systems (GIS) have been recognised as a powerful means to integrate and analyse data from various sources in the context of comprehensive floodplain management. As part of this comprehensive approach to floodplain management, it is very important to be able to predict the consequences of different scenarios in terms of flooded areas and associated risk. Hydrologic and hydraulic modelling plays a crucial role and there is much to gain in incorporating these modelling capabilities in GIS. This is still a rather complex task and research is being done on the full integration of these models. Interfacing between these models and GIS may be a very efficient way of overcoming the difficulties and getting very good results in terms of engineering practice. This paper presents results based on the use of Intergraph GIS coupled with Idrisi GIS. Using these two systems substantially increased the flexibility of using GIS as a tool for flood studies. A lumped (XSRAIN) and a distributed (OMEGA) hydrologic models were used to simulate flood hydrographs. The well known HEC-2 Hydraulic model was used to compute flooded areas. These models were applied in the Livramento catchment with very good results. The computation of flooded areas for different flood scenarios, and its representation in GIS, can be used in the assessment of affected property and associated damages. This is a very useful GIS-based approach to floodplain management. 相似文献
113.
P. T. Tsilingiris 《Renewable Energy》1996,9(1-4)
An analysis is presented for the monthly performance evaluation of a simple design low cost solar water heating systems. A sample of typical results is presented which confirms their suitability as solar heating systems for summer peacking or as solar preheaters for year around loads. 相似文献
114.
H. Perez-Blanco 《International Journal of Refrigeration》1993,16(6):429-433
The search for high-efficiency, gas-fired cooling cycles has led to the development of dual-loop absorption machines with cooling coefficients of performance (COPs) in the 1.2 to 1.7 range. This increased performance may call for high generator temperatures, new working fluids or new materials of construction. In most cases, two different sets of working fluids are required. The conceptual design presented here is aimed at obtaining high efficiencies with relatively low temperatures, employing only one set of fluids. The concept consists of two loops coupled in a configuration aimed at minimizing the loss of thermodynamic availability incurred when transferring refrigerant between the loops. The working fluid pair is a solution of lithium bromide-water. The calculated COPs are of the order of 1.8. The cycle relies on an elaborate evaporator-absorber combination. The paper presents the conceptual design, the critical assumptions, and the performance calculations for the concept. 相似文献
115.
KEITH A. SCHIMMEL ALIEU WURIE SHAMSUDDIN ILIAS JAN E. PEGRAM 《Journal of food science》1996,61(3):577-580
We tested the feasibility of using polymer membranes for a self-hydrating packaging system to reconstitute freeze-dried foods using nonpurified water. Several commercial membranes were screened according to (1) hydration rate, (2) water permeability, (3) passage of microorganisms, (4) salt rejection, and (5) strength. The most promising membranes were used for developing and testing prototype packaging systems. A feasible self-contained rehydration system was a nylon-6 polyamide membrane that rehydrated the freeze-dried food within 30 min while passage of microorganisms was prevented. The temperature was 37°C, and the food contained 0.5g/5g of a low molecular weight solute (salt). Such self-contained membrane rehydration systems must be designed to accommodate expected environmental conditions such as temperature, relative humidity, and nature of the product. 相似文献
116.
三氯乙烯与糠醛水溶液的液液平衡及萃取模拟计算 总被引:3,自引:0,他引:3
本文采用液液平衡釜了糠醛水溶液与三氯乙烯的液液平衡数据,用UNIQUAC方程关联糠醛-水-三氯乙烯体系的液液平衡数据,以UNIQUAC方程的模型,采用液液萃取法模拟计算糖醛和水的分离结果。 相似文献
117.
文章通过对洋浦电厂海水冷却箱涵沟槽预裂(深孔)爆破技术的研究,提出了复杂地质条件下合理的控制爆破参数及微差起爆方式。针对砂层地段难以钻、爆的特点。笔者进行了有益的探讨。 相似文献
118.
119.
钠水玻璃涂料的固化技术及其应用 总被引:3,自引:0,他引:3
崔中敏 《山东建筑工程学院学报》1996,11(3):103-106
论述了五种固化剂改性钠水玻璃的原理及在涂料中的应用,重点介绍了用可溶性金属盐必性钠水玻璃制作涂料的技术关键。 相似文献
120.
以往对电站技术供排水系统大都未进行水力平差计算,致使一些实际电站的供排水系统达不到预期的效果,甚至影响机组的正常运行。据此,给出了供排水管网的平差计算方法,有利于正确评估电站管网,另外,提出了管网校核应注意的问题。 相似文献