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排序方式: 共有715条查询结果,搜索用时 265 毫秒
71.
S. C. Zhou * O. L. Shuai T. T. Wong * T. P. Leung * ** This Project is Supported Partly by National Natural Science Foundation of China 《国际设备工程与管理》1997,(4)
ANovelParsimoniousNeurofuzzyModelAppliedtoRailwayCariageSystemIdentificationandFaultDiagnosisS.C.Zhou,O.L.Shuai+,T.T.Wong?.. 相似文献
72.
用传统回次统计法和用分段统计法对上千个钻孔的RQD值的统计结果表明,选用回次统计法普遍存在与工程实际情况产生一定的偏离;若用孔段统计法,其结果与工程实际情况比较吻合. 相似文献
73.
The 1993 stimulation tests carried out in well GPK1 at Soultz, Alsace, France, showed that out of the thousands of fractures cross-cutting the granite, only a limited number of natural fractures contributed to fluid flow. A comparison between the petrophysical properties of the rock and the interpretation of the hydraulic test results is proposed as a means of determining the distribution of the natural permeable fractures. Gamma-ray spectral logs and other geophysical logs (caliper, bulk density, P-wave slowness, and photoelectric factor) revealed some petrographical variations within the Soultz massive granite, as well as altered/fractured zones that act as preferential pathways for fluid flow as indicated by flow logs. Fluid losses during circulation tests have been estimated on the basis of statistical analysis of gamma-ray readings, and of potassium and thorium contents. 相似文献
74.
用计算机对地质结构面进行统计的算法 总被引:1,自引:0,他引:1
本文根据 Schmidt 网的一般制作原理,设计了一套既能在 Schmidt 网上统计出地质结构面的极点数,又能绘制出极点密度等值线图的算法和计算机程序。利用这套程序制作图件,不仅可成倍提高工效而且可以提高制图精度。由于该套程序是用 BASIC 语言编写,故操作使用方便,而且易于移植到 PC—1500或 PB—700这类微型计算机上去。 相似文献
75.
Jana Hubálková 《Cement and Concrete Research》2003,33(5):747-753
The influence of the spatial arrangement of aggregates on the cold crushing strength (CCS) of refractory castables is studied by means of methods of point process statistics. Two series of self-flowing refractory castables differing in the kind of aggregates used (tabular alumina, corundum balls) are analysed using quantitative image analysis and methods of spatial statistics. Their spatial variability is described by means of the pair correlation function (pcf) and the density function of the nearest neighbour distance (nnd) distribution. It is shown that both characteristics, pcf and nnd, are in close correlation with CCS. 相似文献
76.
我国棉本色纱线GB/T398-93国家标准和现行的棉纱线行业标准落后于当前棉纺企业生产的发展和市场贸易的需求,文章将国内棉纺企业的棉纱质量与瑞士Uster公司对世界环锭纺纯棉纱质量数据统计值进行了对比,提出了修订我国纯棉环锭纱质量标准的一些想法,供标准起草单位参考。 相似文献
77.
Results from recently conducted collaborative trials on the determination of aflatoxin B1 in various matrices have been evaluated to establish whether the use of recovery data would result in a distinct change of the relative between-laboratory standard deviation (RSDR) of the corrected data compared with the uncorrected data. In addition, we applied conventional and robust statistics to evaluate whether the impact of the use of recovery data on the estimation of RSD R depended on the statistical method applied for data analysis. This investigation was based on means before and after correction for recovery. The method performance characteristics were calculated using results from naturally contaminated test materials, while the results from test materials fortified with the target analytes were used to estimate the recovery. The study revealed that applying conventional and robust statistics in general led to comparable estimates for RSDR. The comparison about the use of recovery data showed that in most cases, the RSDR obtained from the analysis of aflatoxin B1 decreased after correction of the results for recovery. This tendency was similar when the comparison was done using robust or conventional statistics. However, in three cases, conventional statistics yielded a higher RSDR for the corrected data, whereas robust statistics showed the opposite. Looking carefully at the data, the treatment of conventional statistics indicated that the way outliers are detected and removed could result in an under- or overestimation of RSDR. Applying the law of error propagation revealed that most likely the correlation between the uncorrected data and the recovery rate led to a reduced variability of the data corrected for recovery. 相似文献
78.
扬声器及其系统频率响应的统计学特性参数 总被引:1,自引:0,他引:1
随着计算机辅助测试(CAT)技术的发展,直接测量扬声器及其系统的频率响应特性函数(SPL)已经变得容易,通过对其进行统计学分析,可以得出新和一组有用的参数,包括SPL标准差、SPL离散系统、SPL峰度系数等。这些参数如果能够推广为扬声器及其系统的常用性能参数,将能够填补Thiele-Small参数的一些盲点,给质量标准的制订、工程的应用等都带来了不少方便。 相似文献
79.
I. R. Savage 《TEST》1980,31(1):321-328
Summary A Bayesian decision-theoretic approach appears to me as a sensible idealization of a guide to behaviour. At the same time
I would like to understand why my behaviour is not always of this form: I sometimes use randomization and I sometimes find
confidence intervals acceptable. Not all of my problems have an explicit cost function. Am I lazy or irrational? Do I use
non-Bayesian conventions to help communicate? Is the cost of rationality-computation missing from the Bayesian model? 相似文献
80.
Lee Schipper 《Energy and Buildings》1984,6(1):15-38
We describe energy use in Swedish homes from 1963 to 1980 using data assembled and analyzed for the first time. Changes in energy use by fuel and purpose before and after the 1973 oil price shock are illustrated and discussed, and savings in space heating in the year 1980, compared with the pre-embargo period, are quantified. We discuss two important elements of Swedish energy conservation policy, the building codes and the system of grants and loans to homeowners. We conclude that the grants and loans probably accelerated home retrofit measures, while the building codes will play an important role in reducing residential heat losses over the long term. 相似文献