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91.
Wheat straw is a potential cellulosic feedstock for bioethanol. This study was conducted to evaluate straw yield potential and its relationship with grain yield for wheat (Triticum spp.) grown in the United States. The specific objective was to determine if differences in straw yield and harvest index (HI) exist between and within regions and/or wheat classes. Using on-going variety performance trials in eight states, a total of 255 varietal trial entriess from five classes of wheat were surveyed for above-ground biomass. Averaged over all wheat classes and regions the HI was 0.45. Soft red winter wheat in Kentucky had, on average, the highest HI and lowest straw yield among regions and wheat classes. Soft white winter wheat under irrigation in the Pacific Northwest produced the highest straw yield. Hard red winter wheat in the southern plain states of Texas and Oklahoma had, on average, the lowest HI. Differences in the amount of precipitation and cultivars were the major contributors to the variation detected within wheat classes. The amount of wheat straw available as cellulosic feedstock in a state or wheat class can be estimated using the grain yield estimates provided by the National Agricultural Statistics Service and the class specific HI. 相似文献
92.
针对传统商业智能存在移植性、集成性和可扩展性差等弱点,该文研究基于.Net Remoting的商业智能平台。在分析商业智能当前应用状况和商业智能体系结构的基础上,给出了整个系统比较完善的解决方案,构建了基于.Net Remoting服务的商业智能的应用平台,该平台可以将商业智能组件无缝集成到企业现有的系统中,增强了可理解性和可扩展性。 相似文献
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数据仓库与决策支持在医院信息系统中的应用 总被引:1,自引:0,他引:1
我国现阶段医院普遍建成了自己的医院信息系统,但是从数据应用的角度来看,大多还只是停留在数据保存、查询的层次上.在医院管理中,一方面大量数据从业务数据库中导出后未得到利用,形成严重的资源浪费,另一方面现代医学与医院管理决策却需要大量的临床数据.如何管理医院中的日常业务数据,提高数据的利用等级,已经成为医院信息系统向纵深发展的重要课题. 相似文献
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基于数据仓库的EIS数据管理体系结构 总被引:2,自引:0,他引:2
该文采用数据仓库的思想构建了EIS的数据管理体系结构,以满足EIS的数据分布性、格式多样性和结构复杂性的要求,克服了现有EIS响应速度低、可用性差等方面的缺陷。在该体系结构中,分别设置了硬信息获取、软信息挖掘模块和硬软信息集成、链接模块,并就实现的关键技术提出了解决方式。 相似文献
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在分析计算机审计的特点及需求的基础上,借鉴数据仓库、OLAP、数据挖掘等技术的优势,提出了一种新型的计算机审计模型.该模型克服了传统审计软件的不足,有效地解决了面对海量数据的审计等问题,提高了审计的效率及质量.最后还对智能审计的发展作了一定的探讨. 相似文献
98.
在比较了数据仓库与传统数据库的区别的基础上,讨论了数据仓库系统的基本结构,数据仓库化的步骤和技术;认为数据仓库,联机分析处理和数据挖掘的结合将成为决策支持系统的重组成部分;并且提出了数据市场是实现数据仓库中间过渡形式,以企业销售情况分析 做了数据市场中数据存储形式的初步设计。 相似文献
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Edgardo GiordaniSaer Doumett Stefania NinMassimo Del Bubba 《Food research international (Ottawa, Ont.)》2011,44(7):1752-1767
Diospyros kaki Thunb. (Ebenaceae) is a widely cultivated tree species in some countries of Asia, while in other continents persimmons are mostly considered “exotic” fruits. Peculiar characteristics of this species are a complex sex expression, parthenocarpy and fruit astringency at harvest time, associated with a different composition in polymerized flavan-3-ols. Analytical methods for determining sugars, vitamin C, carotenoids and polyphenols in persimmons were critically reviewed in order to evaluate the overall significance of literature results; the nutritional and nutraceutical properties, together with the health benefits of both astringent and non astringent cultivars, were also overviewed. To these aims, the available literature from the last twenty years and the most important formerly published papers were investigated using SciFinder®, Elsevier SciVerse, AGRIS, and PubMed search engines. Persimmons resulted rich in sugars (about 12.5 g/100 g FW), being fructose, glucose and sucrose the major components, and in total vitamin C, for which 100-150 g of fresh persimmon supplies the recommended daily amount. Astringent varieties supply higher amounts of sugars than nonastringent ones; conversely, higher concentrations of total vitamin C were found in nonastringent cultivars. The main carotenoid components are ??-cryptoxantin (193 ??g/100 g FW), ??,??-carotene (113 ??g/100 g FW) and ??,??-carotene (30 ??g/100 g FW). Persimmons are also a good source of polyphenolic compounds such as p-coumaric acid, catechin, epicatechin, epigallo catechin, and condensed proanthocyanidins. This chemical composition, together with in vivo and in vitro studies, suggests a relevant role of persimmon in the protection against free radicals and in the prevention of some human diseases. 相似文献