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Water-Tank Studies of Separating Flow Over Rough Hills   总被引:1,自引:1,他引:0  
The present work investigates the lower boundary condition for flows over a steep, rough hill. Simple asymptotic arguments together with the mixing-length hypothesis are used to derive a local analytical solution that is tested against three different flow conditions. In all, 36 velocity profiles are compared with the proposed expression. The experiments were carried out in a water channel and velocity measurements were made through laser Doppler anemometry. The extent of separated flow was made to vary as a function of the roughness and the Reynolds number. The analysis includes regions of attached as well as separated flow. In particular, the solution of Stratford is studied at the points of separation and re-attachment and found to apply equally well in rough walls.  相似文献   
124.
The extent to which flag States are bound by the conservation rules of regional fishery management organisations is an important question in the quest to reduce unregulated fishing. The European Union implemented a trade suspension against Cambodia under Council Regulation 1005/2008, in response to unregulated fishing by Cambodian vessels in high seas areas managed by regional fishery management organisations. Limitations in the arguments underpinning the decision evidence the flaws of unregulated fishing as a legal concept, underlining the need for it to be appropriately interpreted and contextualised in the international legal framework. Clarity on the differences between conventional and customary sources of international legal obligation, and their implications for State consent, should guide the implementation of the Regulation to maximise the normative potential of resulting practices.  相似文献   
125.
On 23 September 2016, a workshop entitled “Innovating for change in global fisheries governance” was held in Tromsø, hosted by the K. G. Jebsen Centre for the Law of the Sea (JCLOS) at the Faculty of Law of UiT, The Arctic University of Norway. The aim of the workshop was to address the following question: How can international law be used as an innovative mechanism for change in global fisheries governance? Seven of the papers presented at the workshop, each one addressing a particular aspect of this overarching question, are published here in this special issue of Marine Policy.  相似文献   
126.
为全面提升潍坊市国土资源执法监察工作效能,规范执法监察程序,提高执法监察工作效率,根据国土资源部和省国土资源厅关于“科技执法”的工作要求,按照省、市国土资源“一个平台、两个市场”总体建设方案,基于潍坊市国土资源局综合管理服务平台和“一张图”数据中心,以国土资源执法监管为核心,建立市、县、乡一体化的潍坊市国土资源局执法监察平台,创新国土资源违法发现机制,实现执法过程实时监控,建立图文档一体的违法案件发现、查处管理系统,建设12336违法举报系统,切实提高全市国土资源执法监察工作水平。  相似文献   
127.
Zipfs Law originally was proposed as a guide to a statistical distribution in social studies. The law describes a relationship between size and rank of discrete phenomena. It is a variant of Paretos 1927 Law known as the 80/20 rule and is similar to Bodes Law in concept. The relationship described by Zipfs Law is a succession of order data with the largest followed by half the size for the next largest, which in turn, the next is half that size, and so on. In geology, it has been used with moderate success in resource assessment of mining and petroleum. In essence, it predicts how many entities of a certain size may be left in a sequence of decreasing size assuming the largest has been ascertained. Examples of applications would be plotting the rank and size of ore deposits or oil fields to determine how many deposits remained undiscovered and their size. After a flurry of papers in the 1970s and 1980s, application of the law apparently either was successful and thus not reported in way the literature or was determined to be ineffectual and its use discontinued, but either way the law lapsed into obscurity. Examples of oil- and gas-field size in Kansas, the occurrence of historic earthquakes that affected the state, and size of anticlines (plains-type folds) are presented to illustrate application and limits of Zipfs Law.  相似文献   
128.
非饱和流节点间导水率估计及达西平均分析   总被引:1,自引:0,他引:1       下载免费PDF全文
针对由Gardner-Russo函数描述的特征土壤,在双饱和度坐标系中,探讨了常规节点间导水率估计与量纲一水平达西平均(k*H)和量纲一垂直达西平均(k*V)的差异.k*H是相邻两节点饱和度的函数,而k*V也是空间步长(Δx)和特征参数(α)的函数.对水平非饱和流,算术平均高估导水率,而几何与调和平均低估导水率;从相对误差空间分布看,几何平均优于算术和调和平均.对垂直非饱和流,随Δx(或α)的增大,常规估计的相对误差空间顺(或逆)时针旋转并缩小,从而降低模型准确性.k*H等值线具有对称性,而k*V不具对称性;仅当Δx或α足够小时,k*H才趋近于k*V.因此,为提高非饱和流数值模拟的准确性,必须采用精确的达西平均来计算节点间导水率.  相似文献   
129.
This is a historical review of Canadian policy at the Third UN Conference on the Law of the Sea. Canadian objectives with regard to the territorial sea, fisheries, pollution prevention and the continental shelf are outlined and the role played by the Canadian delegation at UNCLOS is described. The article then examines the impact of the Convention on Canada, particular attention being paid to the Canadian Exclusive Economic Zone and the Canadian role in the controversy over seabed mining. The author concludes by arguing that Canada was a major beneficiary of the Convention, but that US opposition has placed the future of the Convention in jeopardy.  相似文献   
130.
本文就各级测绘行政管理部门,如何充分发挥政府行政管理作用,履行依法行政职能,保障和促进测绘事业的健康持续发展等重要问题。分析了现代测绘管理基本特点,论述了测绘管理部门依法行政和依法管理的基本思路和工作要求。  相似文献   
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