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图书馆权利就是图书馆员、图书馆读者和图书馆自身的权利。在我国现有的图书馆法制中,对图书馆权利的规定大多是不全面的。而图书馆法制中图书馆权利的缺失影响了图书馆法的价值。在论证我国现有图书馆法制中图书馆权利缺失现象的基础上,分别使用归纳与演绎的方法论证了图书馆权利存在于图书馆法中的正当性。 相似文献
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H. G. Allore D. J. Wilson H. N. Erb P. A. Oltenacu 《Preventive veterinary medicine》1998,33(1-4):11-29
The data for this cross-sectional retrospective study are from surveys of 65 dairy-cattle herds in central New York, USA sampled between February, 1993 and March, 1995. The objective was to identify probability distributions of logarithmically transformed somatic-cell counts (linear score) for use in a simulation model of mastitis and milk quality. Probability density functions were estimated using maximum-likelihood estimators for the linear score of individual-cow compositemilk samples culture negative and culture positive for the pathogens Streptococcus agalactiae, Streptococcus non-agalactiae, Staphylococcus aureus, and coagulase-negative staphylococci for the complete dataset and by bulk-tank somatic-cell count group (< 500 000, ≥ 500 000 SCC/ml). Based on the rankings of three goodness-of-fit tests (Anderson-Darling, Kolmogorov-Smirnov and x2), the Weibull distribution (among the three top-ranking distributions for 14 out of 15 cases) may be used to model the individual-cow linear-score response by culture-result-specific bulk-tank somatic-cell count group. A β distribution was among the three top-ranking distributions for nine out of 15 culture-result-specific bulk-tank somatic-cell count groups and has a logical relationship to linear score because it is defined on a fixed interval. On the other hand, the normal distribution had a poorer fit than the Weibull and at least two other distributions for all culture negative and coagulase-negative staphylococci samples. We do not assume that the underlying biological processes are fully explained by either Weibull or β distribution—but modelling the linear score for the above culture results with these distributions provided an adequate fit to the survey data, reduced the need for two-sided truncation that open intervals needed, and had errors that did not appear to be systematically positive or negative. 相似文献
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This paper presents an on-line method for detecting washboarding generated in bandsaws. It uses a parameter based on the shape of sawing force amplitude distributions. The curve of the probability density function of the parallel sawing force amplitude obeyed a normal distribution for the normal sawn surface, but it changed to an M-shaped distribution when washboarding appeared on the sawn surface of the workpiece. The curve of probability density function of the normal sawing force amplitude obeyed the normal distribution for any sawn surface investigated. The workpiece including a knot did not influence use of the parameter for detecting the appearance of washboarding. 相似文献
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为运用概率分级和回归分析方法揭示普通丝瓜褐变度与总酚含量之间的相互关系,从而建立普通丝瓜基于褐变度正态分布的分级标准,研究测定38份普通丝瓜的褐变度和总酚含量。采用X-1.2818S、X-0.5246S、X+0.5246S和X+1.2818S 4个点将丝瓜褐变度概率分为5级,即极低(1级)、低(2级)、中(3级)、高(4级)、极高(5级),并将其与总酚含量进行线性回归分析。普通丝瓜果肉褐变度变化范围为2.17~9.60,平均值为6.211,变异系数为29.77%,经K-S正态性检验符合正态分布,建立褐变度和总酚含量的线性回归方程y=3.559x-2.837,两者之间存在显著的线性关系。普通丝瓜果肉褐变度与总酚含量呈显著正相关。 相似文献
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A mechanistic weather-driven model was developed based on the infection cycle of Aspergillus flavus on maize to predict the risk of aflatoxin contamination in field on a daily basis from silk emergence to harvest; hourly data of temperature, relative humidity and rain were used as model input. The work was done in four steps: (i) development of the model prototype; (ii) collection of Italian field data on aflatoxin contamination in maize with related crop and weather data; (iii) development of a probability index to exceed the legal limit of 5 μg of aflatoxin B1 per kg of unprocessed maize by combining model predictions and field data in a logistic regression; and (iv) validation with Italian data of the probability index and release of the predictive model, named AFLA-maize. Predictions of maize contamination above the threshold of 5 μg/kg in the data set used for parameterization of the regression equation were correct for 73% of field samples; 59% and 14%, respectively, were not contaminated and contaminated. In a second independent data set, 68% of samples were correctly predicted. The model AFLA-maize provides prediction of A. flavus infection and aflatoxin contamination along the growing season and at harvest. This information is useful to support decision-making for (i) crop management, (ii) harvest timing, (iii) maize lots cleaning and logistic, and (iv) maize sampling for aflatoxin analysis at consignment. 相似文献
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根据后裔平均数估计的遗传力的概率分布 总被引:1,自引:0,他引:1
陈廷槐 《黑龙江八一农垦大学学报》1990,(2):41-48
本文导出了根据后裔平均数估计的遗传力的概率分布,并对其数学期望和方差估计进行了讨论。 相似文献
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边坡生态防护工程中的若干问题探讨 总被引:3,自引:0,他引:3
首先,对工程领域重要概念边坡和边坡生态防护进行了定义,接着对边坡进行了分类。在此基础上,探讨了边坡生态工程的野外调查工作。 相似文献
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对长江中下游地区第四纪沉积物发育土壤的电荷特性作了初步研究,结果表明:①土壤有效阳离子交换量(ECEC)值,粘盘壤>粘盘黄棕壤>棕红壤>红壤;阴离子交换量AEC,可变电荷量CECv/CEC_3.2,电荷零点pH_0,粘盘壤>粘盘黄棕壤>棕红壤>红壤。②土壤的电荷特性与土壤的粘粒矿物组成和氧化物数量有关,它可以很好地显示土壤的发育程度,③土壤的电荷特性可用于土壤分类,作者对此提出了相应的指标值。 相似文献