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排序方式: 共有477条查询结果,搜索用时 15 毫秒
1.
介绍了美国DIPPR、德国DETHERM和日本NIST的组织情况和编篡工作,从此得到启示,以求加速我国化工物性数据编篡工作的发展。 相似文献
2.
Since the mid-1970s new types of forest damage are observed in the Federal Republic of Germany. Typical damage symptoms in coniferous tree species are needle yellowing, reddening and premature loss of older foliage. Needle analysis carried out in damaged Norway spruce stands indicated that these phenomena, most of all needle yellowing, are influenced by the nutritional status of the trees. For the investigated sites Mg but also other elements, particularly P, S, K, Ca and Zn may play a causal role. As N is the most abundant element in the plant its form of uptake is important for a balanced nutrition. On the contrary to NO3-N high NH4-N uptake reduces the uptake of cations, particularly Mg and Ca, eventually inducing foliar discoloration symptoms on specific sites. Fertilizer experiments indicated that Mg fertilization is an appropriate tool to mitigate forest damages associated with Mg deficiency for a sustained time period. The application of N in the form of NH4-N may impede Mg uptake. This mechanism may cause severe damage in forest areas receiving continuously high NH4-N deposition. 相似文献
3.
刘秀梅 《湖南工业职业技术学院学报》2010,10(2):101-104
德国"双元制"职业教育以其行动导向的实践与理论,企业与学校紧密结合的学习,即学习与工作结合,在工作中学习的职业教育模式,突显其价值与效益,在国际职业教育比较中颇具强势。文章从高职教育的发展趋势,对"双元制"职业教育的特点和结构改革进行分析和探讨,提出了发展我国职教尤其是女性职业教育改革的几点建议。 相似文献
4.
德国老年人药物管理系统设计研究 总被引:1,自引:1,他引:0
目的针对德国老年人用药问题进行分析,运用智能药物管理系统,提出解决方案。方法重点分析了德国人口老龄化产生的健康问题,阐述了老年用药方面的问题,提出了用药过程中针对患者、医生、药店有机结合的智能药物管理系统的设计原则和案例。结论人口的老龄化和老年人的健康是全球面临的问题,在"互联网+"健康的基础上,设计人性化的智能药物管理系统,可以为老年人健康生活带来更多的便利。 相似文献
5.
Regularly updated land cover information at continental or national scales is a requirement for various land management applications as well as biogeochemical and climate modeling exercises. However, monitoring or updating of map products with sufficient spatial detail is currently not widely practiced due to inadequate time-series coverage for most regions of the Earth. Classifications of coarser spatial resolution data can be automatically generated on an annual or finer time scale. However, discrete land cover classifications of such data cannot sufficiently quantify land surface heterogeneity or change. This study presents a methodology for continuous and discrete land cover mapping using moderate spatial resolution time series data sets. The method automatically selects sample data from higher spatial resolution maps and generates multiple decision trees. The leaves of decision trees are interpreted considering the sample distribution of all classes yielding class membership maps, which can be used as estimates for the diversity of classes in a coarse resolution cell. Results are demonstrated for the heterogeneous, small-patch landscape of Germany and the bio-climatically varying landscape of South Africa. Results have overall classification accuracies of 80%. A sensitivity analysis of individual modules of the classification process indicates the importance of appropriately chosen features, sample data balanced among classes, and an appropriate method to combine individual classifications. The comparison of classification results over several years not only indicates the method's consistency, but also its potential to detect land cover changes. 相似文献
6.
宛岩 《宁波工程学院学报》2013,(2):23-27
本文在分析德国港口与内陆间低碳型多式联运模式的基础上,研究德国低碳型多式运输模式的特点,从各种运输方式的组合等方面,探讨低碳型多式联运模式的利弊,通过对德国港口与内陆间低碳型多式联运模式的分析,进而提出对我国物流运输的启示。 相似文献
7.
德国化妆品安全的法律基础 总被引:2,自引:0,他引:2
化妆品安全的法律建设,既是保证化妆品安全、保护人体健康的需要,也是在国际贸易中实施本国环境战略的需要。简要论述了德国化妆品安全方面的法律法规和法律要求,以期在我国化妆品安全的法律建设中起参考作用。 相似文献
8.
Shiu-Fai Wong 《Industry and innovation》2005,12(1):117-145
This paper firstly examines the relationship between state coordination and wind energy growth by comparing the differences between UK and German institutional configurations and state involvements in the 1990s. While the EU was calling for a unified regulatory framework for its member states, the UK and Germany adopted very different renewable energy policies. The evidence of the early 1990s shows that the British government employed “deregulation” with so limited state involvement that wind energy project developers faced thorny development problems, while the German government tried to require the electricity supply industry to purchase expensive wind power by “regulation” but encountered formidable resistance. Nevertheless, both the British and German administrations later could resolve these problems through new forms of state power. This suggests that, firstly, neither “deregulation” nor “regulation” is an effective means to develop wind power with increasing electricity liberalization and regionalization. Secondly, “obliging” regulations and state powers are vital to the policy outcome by harnessing the state's institutional capacity to smooth out technology innovation and diffusion. 相似文献
9.
10.
Using detailed micro-level survey data for three advanced European welfare-state economies (Germany, Netherlands and UK), our analyses suggest a fairly common hierarchy to homeownership, according to partnership status, exists. In all three countries, a variety of interrelated factors appear to encourage greater propensities for homeownership amongst co-residential households (married/cohabiting), as compared to single-person households. However, important macro-contextual differences do appear to play a significant role in mediating the magnitude of difference within this hierarchy. For instance, in Germany the importance of marriage as a predictor of homeownership is found to be particularly strong, with married couples having far higher propensities for homeownership, even when compared to non-married cohabiters. In the Netherlands and UK, where an emphasis on traditional family and marriage is less pronounced, and where homeownership is generally more popular and accessible, the differentiation between married/unmarried partners is greatly reduced. Furthermore, we find no evidence to suggest that living-apart-together partners are more/less likely to own their home than singles. 相似文献