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1.
本文分析了"十五"期间农村水电发展情况,对"十一五"农村水电发展政策环境及增长情况进行了预测。 相似文献
2.
均匀设计法分析制备过程对钴钼硫化物催化剂机械强度的影响 总被引:1,自引:1,他引:0
建立了CoMoP/Al2O3加氢精制催化剂机械强度及其可靠性在制备过程中的数学模型,采用均匀设计考察了浸渍、干燥、煅烧、硫化4个制备过程中,浸渍时间、干燥温度、干燥时间、煅烧温度、煅烧时间、硫化温度和硫化升温速率7个实验因子对催化剂强度均值、Weibull模量的影响,同时考察了这些因素对颗粒密度的影响。方差分析表明所有模型都是充足的。实验结果表明,硫化过程是影响催化剂强度均值的主要过程。在实验范围内提高硫化温度、降低硫化时的升温速率有利于提高催化剂的强度。影响催化剂Weibull模量的因素主要为各个制备过程的交互效应。要提高催化剂强度的可靠性就必须全面考虑催化剂制备的各个过程,特别是各个制备过程的交互效应。 相似文献
3.
David L. Hoover 《Computers and the Humanities》2003,37(2):151-178
This article examines the usefulness ofvocabulary richness for authorship attributionand tests the assumption that appropriatemeasures of vocabulary richness can capture anauthor's distinctive style or identity. Afterbriefly discussing perceived and actualvocabulary richness, I show that doubling andcombining texts affects some measures incomputationally predictable but conceptuallysurprising ways. I discuss some theoretical andempirical problems with some measures anddevelop simple methods to test how wellvocabulary richness distinguishes texts bydifferent authors. These methods show thatvocabulary richness is ineffective for largegroups of texts because of the extremevariability within and among them. I concludethat vocabulary richness is of marginal valuein stylistic and authorship studies because thebasic assumption that it constitutes awordprint for authors is false. 相似文献
4.
A motivational model of rural students' intentions to persist in, versus drop out of, high school. 总被引:1,自引:0,他引:1
Using self-determination theory, the authors tested a motivational model to explain the conditions under which rural students formulate their intentions to persist in, versus drop out of, high school. The model argues that motivational variables underlie students' intentions to drop out and that students' motivation can be either supported in the classroom by autonomy-supportive teachers or frustrated by controlling teachers. LISREL analyses of questionnaire data from 483 rural high school students showed that the provision of autonomy support within classrooms predicted students' self-determined motivation and perceived competence. These motivational resources, in turn, predicted students' intentions to persist, versus drop out, and they did so even after controlling for the effect of achievement. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
Wood has long traditions as a building material, and is often used in construction elements, and as interior and exterior surfaces in the Nordic countries. In most applications, there are reaction to fire requirements to products used as surfaces, e.g. in escape routes and larger public spaces. Most wood products will therefore have to be treated with fire retardant (FR) agents to fulfil the strict requirements to properties connected to heat release and flame spread. Unfortunately, FR agents usually also increase the smoke production, as they cause a more incomplete combustion of the wood. The wood product manufacturers seek to find the optimal amount of FR additives where both heat release and smoke production in the classifying test are within the requirements given in the building regulations. This paper describes models for prediction of the European reaction to fire classes of wood products. The models are based on multivariate statistical analysis, and use test results from the cone calorimeter test as input. The presented models are, with very good precision, able to predict which Euroclass and additional smoke class a wood based product would obtain if it were to be tested in the single burning item test. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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7.
加强农村广播电视的发展,提高其覆盖率是关键,针对这一问题,阐述了解决农村广播电视覆盖的手段,对农村广播电视覆盖现状做了详细的分析,并提出建议和措施。 相似文献
8.
An assessment of hydrocarbon and metal/metalloids (arsenic, cadmium, copper, lead, mercury, selenium, zinc) contamination in sediments from Lake Mulwala, Australia, was undertaken. The objectives of the study were: (i) to determine the extent of contamination in the lake sediments, compared to Australian and international sediment quality guidelines, and (ii) to attempt to identify the contaminant sources to the lake. With the exception of a few samples containing elevated levels of arsenic and/or mercury, the levels of all contaminants in the sediment samples taken from the lake were below the ‘lower trigger’ of the Australian Sediment Quality Guidelines that would warrant further investigation. High molecular weight hydrocarbons (up to 700 mg kg−1) were found in most sediment samples. Non‐metric statistical analysis indicated that the contaminant distribution was different in different parts of the lake, with the lowest concentrations generally found at the influent to the lake. No definitive source(s) of contamination could be identified for either metalloids or hydrocarbons. 相似文献
9.
A stochastic model is proposed for a basic mechanism in the formation of uncertainties in physical quantity measurements.
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Translated from Izmeritel'naya Tekhnika, No. 1, pp. 12–17, January, 2006. 相似文献
10.
李建军 《南水北调与水利科技(中英文)》2006,4(B06):98-99
对围场县“十五”农建工作取得的成就和经验、体会进行了总结,阐述了农建在当地农村经济中的重大支撑作用,并对“十一五”农建工作进行展望。 相似文献