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221.
分析了乡级自动雨量站与自动气象站雨量资料融合的必要性,介绍了资料融合的思路与方法。通过这种方法,实现了商丘市两种雨量资料的完全共享。 相似文献
222.
Nepheline syenite plutons emplaced within the Terrane Boundary Shear Zone of the Eastern Ghats Mobile Belt west of Khariar
in northwestern Orissa are marked by a well-developed magmatic fabric including magmatic foliation, mineral lineations, folds
and S-C fabrics. The minerals in the plutons, namely microcline, orthoclase, albite, nepheline, hornblende, biotite and aegirine
show, by and large, well-developed crystal faces and lack undulose extinction and dynamic recrystallization, suggesting a
magmatic origin. The magmatic fabric of the plutons is concordant with a solid-state strain fabric of the surrounding mylonites
that developed due to noncoaxial strain along the Terrane Boundary Shear Zone during thrusting of the Eastern Ghats Mobile
Belt over the Bastar Craton. However, a small fraction of the minerals, more commonly from the periphery of the plutons, is
overprinted by a solid state strain fabric similar to that of the host rock. This fabric is manifested by discrete shear fractures,
along which the feldspars are deformed into ribbons, have undergone dynamic recrystallization and show undulose extinction
and myrmekitic growth. The shear fractures and the magmatic foliations are mutually parallel to the C-fabric of the host mylonites.
Coexistence of concordant solid state strain fabric and magmatic fabric has been interpreted as a transitional feature from
magmatic state to subsolidus deformation of the plutons, while the nepheline syenite magma was solidifying from a crystal-melt
mush state under a noncoaxial strain. This suggests the emplacement of the plutons synkinematic to thrusting along the Terrane
Boundary Shear Zone. The isotopic data by earlier workers suggest emplacement of nepheline syenite at 1500 +3/−4Ma, lending
support for thrusting of the mobile belt over the craton around that time. 相似文献
223.
文中从地理信息系统、遥感技术、全球定位系统、无线通讯技术等方面介绍了信息技术在加拿大的发展和应用情况。地理信息系统是空间信息管理的平台,在政府和许多行业中有广泛的应用,在互联网上掀起了电子地图和位置搜索的应用浪潮;遥感技术是信息采集的重要手段,在数据处理技术方面不断进步,广泛应用于城市和环境研究;全球定位系统是空间定位的重要工具,包括导航GPS和测量GPS两大应用领域;通讯技术是信息传递的基础,无线通讯网的发展,为分布式移动计算创造了条件。随着各种信息技术的发展和普及应用,一种以空间信息服务为特征和载体的产业G-business正在形成。 相似文献
224.
225.
A. Jones B. Barnett A.J. Williams J. Grayson S. Busilacchi A. Duckworth E. Evans-Illidge G.A. Begg C.D. Murchie 《Continental Shelf Research》2008
Often, research activities in Torres Strait have not delivered full benefit to Torres Strait Islanders due to a lack of consultation, ineffectual communication of research information and lack of empathy for the needs of Islander communities. As for other stakeholder groups, integration of Islanders into the research process through practical involvement in research may overcome these problems. Three case studies from research projects conducted in Torres Strait are discussed to highlight a variety of communication and engagement activities carried out by non-Indigenous researchers. How these communication and extension activities facilitate collaboration between Torres Strait Islander and non-Indigenous researchers provides insight in the importance of these activities to the relative success of research projects. 相似文献
226.
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228.
运用差分GPS动态获取高精度土地资源变化数据的新技术 总被引:9,自引:0,他引:9
由于经济的飞速发展,许多耕地被占用变为非农业用地。土地管理部门需要及时准确地掌握城镇和农村用地的变化格局,为耕地保护政策的制定提供依据。但传统的土地变更测量方法存在难于准确获取变化边界坐标,成图困难且周期长、人为操作随意性大等不足。在分析各种GPS差分技术的基础上提出了运用移动差分GPS技术获取土地利用变化信息的新方法。作为国家“九·五”攻关项目的研究内容,该方法在包头市郊区县进行了实验,结果证明与传统测量方法相比,具有快速、准确,操作简便,GPS数据输入GIS,可以快速成图等优点。 相似文献
229.
It has been suggested that the fisheries management process with multiple, informed stakeholders and socio-economic, political, and scientific complexity can be considered a governance network. This exploratory study applied communication network analysis (CNA) measures and methods to assess two cases of US federal fishery management in the Northwest Atlantic—Atlantic herring and sea scallop. Through questionnaires and interviews, CNA maps were constructed and quantitative measures of network structure and function (density, weighted average path length) and centrality measures for individual network members (degree, betweenness) were derived using InFlow software. The results show that fishery governance networks are horizontally and vertically integrated across levels of government and public–private–nonprofit sectors. The findings validated existing understanding of fisheries management as a contested, competitive management context among stakeholders, and provided new insights about the effectiveness of information sharing across the network and the critical role of bridgers connecting disparate subgroups. Fisheries management can be conceptualized and analyzed as governance networks, and the paper discusses additional research questions, refinements needed for application of the research methods, and ramifications for managers (e.g., can resource managers manage networks). 相似文献
230.
目前,岩体边坡稳定性的分析多数采用极限平衡法将边坡一律按照刚体进行分析,没有考虑软弱夹层的影响,但对于岩体内部存在多个软弱带(层)的边坡看做是一个刚性体是不切合实际的,那如何考虑它们之间的相互作用,目前还是一个空白,没有这方面的研究。鉴于此,在塑性极限分析理论的基础上,将内部存在多个软弱带(层)的边坡视为刚塑性体,提出利用机动位移法、采用能量系数对存在单个或多个平面型软弱夹层的岩体边坡进行稳定性评价方法,并推导了相应计算公式,同时,利用典型实例进行了验证,并与传统的极限平衡法结果进行了对比,证明了该方法的可行性和实用性,具有很高的实用价值。 相似文献