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111.
R. A. Wood 《Nutrient Cycling in Agroecosystems》1990,26(1-3):89-98
The amounts of N and K fertilizers used in the South African sugar industry have increased dramatically in the past four decades, due partly to an increase in the area under sugarcane but also to large increases in the amounts of N and K fertilizers applied per hectare. There has also been an increase in the amount of P fertilizer used but this has been more gradual. The main fertilizer carriers for cane and their relative efficiency are discussed. During this period there has been considerable research into the nutrient requirements of sugarcane. Correlations established between soil and leaf analysis and crop responses to N, P and K fertilizers, and their effects on cane quality, are reviewed. While fertilizer recommendations based on soil and leaf analysis have provided a useful guide for determining the nutrient requirements of cane, they are continually being modified in the light of current research. 相似文献
112.
软件测试作为软件质量的保证,受到了IT行业的高度重视。测试用例的设计是软件测试的主要内容。重点分析了测试用例的优点和不足,建议针对不同的软件项目采取不同的测试用例设计方法。 相似文献
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《The Journal of Strategic Information Systems》2014,23(1):45-61
Information systems (IS) are strategic in so far as they are used to realize strategic intent. Yet, while much has been said about aligning IS functionality with the strategic intent and how to organizationally implement strategically aligned systems, less is known of how to successfully implement strategic change associated with system use – a truly critical challenge within strategic IS implementation. Drawing on a strategy-as-practice perspective we address this gap by developing a multi-dimensional view of IS strategy, conceptualizing three key challenges in the IS strategy process, to explain how and why a paper mill, despite successfully implementing a strategic production management system, failed to produce intended strategic change. We call this outcome strategy blindness: organizational incapability to realize the strategic intent of implemented, available system capabilities. Using a longitudinal case study we investigate how cognitive rigidity of key actors and fixed, interrelated practices shaped the implementation of the new production system. We also identify core components and dynamics that constitute a richer multi-dimensional view of the IS strategy implementation (alignment) process. In particular, we identify three salient factors that contribute to strategy blindness – mistranslation of intent, flexibility of the IT artifact and cognitive entrenchment – and discuss how they affect strategic implementation processes. We conclude by discussing implications of our findings for IS strategy theory and practice, especially the contribution of strategy-as-practice to this stream of research. 相似文献
116.
介绍了FDA的化妆品配方自愿登记计划(VCRP)及参与的好处,对《化妆品与盥洗用品》杂志公布的近30年来的的化妆品防腐剂使用频率数据进行了整理,描述了历次统计前20位品种的变迁,对一些重要品种,如重氮咪唑烷基脲、咪唑烷基脲、二羟甲基二甲基乙内酰脲、甲醛类、季铵盐-15、布罗波尔、异噻唑啉酮类、碘代丙炔基于基氨基甲酸酯(IPBC)、三氯生、苯氧乙醇和尼泊金酯类等的走势和应用进行了介绍。 相似文献
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本文利用程序静态分析技术对Web程序中的用例识别进行了深入研究。对Web页面的用户行为进行了深入分析并建模,从行为模型中提取出描述整个系统中用户行为的事件流图,结合采用现有的从目的成功语句出发、以必经结点为基础的用例识别方法,从各个Web页面中提取的独立控制流图,形成全局控制流图,进行全局用例识别。与以前已有工作相比,本文考虑了Web程序的特点,尤其是前端程序如何实现用户行为,并在前端程序中进行精确的用例识别。本文采用目前使用较为广泛的JSP程序进行了实验,结果表明该方法能够有效识别JSP程序中的用例结构。 相似文献
120.
The process of grinding soybeans to a fine flour and extracting the flour with hexane was studied on a pilot plant scale.
The crude oil from the pilot plant study had 15 ppm phosphorus and was suitable for physical refining after a light acid pretreatment
and bleaching. The refined oil showed a Lovibond color of 1.4 yellow and 0.3 red. The pilot plant study also showed that grinding
of the soybeans and the separation of solid from miscella were the most difficult steps in solvent extraction with fine flour.
A laboratory study on separation of miscella from meal by aqueous ethanol reduced the hold-up volume, but it did not remove
all the miscella. A test with betacarotene showed that only the miscella outside the flour particles was displaced.
Aqueous ethanol solutions used as a second solvent extracted additional nontriglyceride materials (primarily phospholipids)
from the meal. Also, the free fatty acid content of the oil was increased with aqueous ethanol solution wash. The quality
of the extracted crude oil was lowered by using a second solvent, but it had the advantage of needing only one centrifugation
to separate miscella from meal. 相似文献