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131.
基于MVC的J2EE WebGIS数据库模型研究与实现 总被引:1,自引:0,他引:1
对J2EE(Java 2 Enterprise Edition)环境下几种WebGIS应用开发模式进行比较,分析各种模式的优缺点,重点研究基于MVC的设计模式,探讨WebGIS数据的组织,提出一种基于MVC的多层J2EE WebGIS数据库模型架构,应用该模型在Struts框架下实现了上海某区土地部门网络数据库业务系统,该系统不仅较好地支持了该区土地业务部门的业务管理,而且提供了WebGIS子系统,业务人员在进行与土地地理位置相关的业务处理时,能够图形与业务文件互见,大大提高了业务人员的工作效率,验证了提出的模型架构具有较好的可扩展性和易维护性。 相似文献
132.
Traditional El Nino and El Nino Modoki Revisited: Is El Nino Modoki Linearly Independent of Traditional El Nino? 总被引:1,自引:0,他引:1 下载免费PDF全文
The present study revisited the first two leading modes of tropical Pacific sea surface temperature anomalies (SSTA) during the period of 1979-2008. It is suggested that the so-called El Nino Modoki, which is captured by the second mode, exists objectively and exhibits obvious differences from traditional El Nino, which is captured by the first mode, in terms of its spatial characteristics. Furthermore, the authors found that El Nino Modoki is linearly independent of traditional El Nino; hence, it cannot be described as part of the traditional El Nino evolution, and vice versa. 相似文献
133.
人工岛建设在缓解滨海人地矛盾的同时带来新的环境问题。本研究聚焦人工岛建设引起的岸滩侵蚀与泥沙分配失衡问题,以海口西海岸为例,建立GENESIS岸线演变模型,探讨人工岛影响下的海滩地貌演化机制,并在此基础上提出“循环养护”的海滩修复对策。主要研究结论为:①海口湾南海明珠人工岛对邻近海滩的影响以“岛后方淤积、两侧侵蚀”为显著特征,且两侧侵蚀热点区的响应幅度存在明显差异。五源河口至新国宾馆岸段侵蚀更为强烈的主导因素为物源匮乏与岸线形态外凸。②通过人工补沙与循环养护相结合的生态修复措施,可实现岸滩泥沙的合理分配与地貌的动态平衡,有效缓解人工岛引起的海岸侵蚀问题。本研究成果可为国内相似类型海岸的岸滩修复提供良好的借鉴意义。 相似文献
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Toshiyuki Kurihara Kazuhiro Tsukada Shigeru Otoh Kenji Kashiwagi Minjin Chuluun Dorjsuren Byambadash Bujinlkham Boijir Sersmaa Gonchigdorj Manchuk Nuramkhan Masakazu Niwa Tetsuya Tokiwa Gen’ya Hikichi Takafumi Kozuka 《Journal of Asian Earth Sciences》2009,34(2):209-225
Recent mapping projects undertaken in Central Mongolia have revealed the widespread occurrence of radiolarian chert within a Paleozoic accretionary complex. We present the results of the first detailed tectonostratigraphic and radiolarian biostratigraphic investigations of the Gorkhi Formation in the Khangai–Khentei belt of the Central Asian Orogenic Belt.The Gorkhi Formation consists of sandstone shale, alternating sandstone and shale of turbidite affinity and chert with small amounts of siliceous shale, basalt, limestone, and clast-bearing mudstone. Radiolarian chert that is completely devoid of terrigenous clastic material is commonly associated with underlying basalt (sedimentary contact) and with conformably overlying siliceous shale and turbidite deposits. The tectonic stacking of basalt–chert and chert–turbidite successions is the most remarkable structural feature of the formation.The recovery of moderately well-preserved radiolarians and conodonts from red chert led to the recognition of four radiolarian assemblages that have a combined age range from the latest Silurian (Pridolian) to the Late Devonian (Frasnian). No age control exists for the siliceous shale, shale, and sandstone, although they are considered to be latest Devonian or slightly younger on the basis of stratigraphic relationships with underlying chert.The Gorkhi Formation has previously been interpreted as a thick sedimentary basin deposit overlying an unexposed Archean–Neoproterozoic basement; however, the stratigraphy within individual tectonic slices clearly corresponds to that of an ocean plate stratigraphy of an accretionary complex generated by the trenchward movement of an oceanic plate. From the lowermost to uppermost units, the stratigraphy comprises ocean floor basalt, pelagic deep-water radiolarian chert, hemipelagic siliceous shale, and terrigenous turbidite deposits. The biostratigraphic data obtained in the present study provide corroborating evidence for the existence of an extensive deep-water ocean that enabled the continuous sedimentation of pelagic chert over a period of nearly 50 million years. These data, together with structural data characterized by tectonic repetition of the stratigraphy, indicate that these rocks formed as an accretionary wedge along an active continental margin, possibly that of the Angara Craton. The mid-oceanic chert was probably deposited in the Northern Hemisphere portion of the Paleo–Pacific Ocean that faced the Angara Craton and the North China–Tarim blocks. Thus, we propose that subduction–accretion processes along the Paleo–Pacific rim played an important role in the accretionary growth of the active continental margin of the Angara Craton, directly influencing the evolution of the Central Asian Orogenic Belt. 相似文献
136.
国土资源数据中心是国土资源信息化建设的基础设施,数据中心管理系统在数据中心的建立中起着关键作用。本文介绍了省级国土资源信息的业务、数据、平台功能需求分析,设计并实现了一款适合省级国土资源数据中心管理系统。 相似文献
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138.
Spatio-temporal changes in macrozoobenthic assemblage structure were monitored at 8 stations in a river-affected temperate lagoon (Idoura Lagoon, Japan) from May 1997 to May 1998 to assess animal–environment relationships in estuarine soft-bottom habitats. A total of 29 taxa occurred with a predominance of a few polychaete species including Heteromastus cf. similis, Hediste spp., Pseudopolydora cf. kempi and Prionospio japonica. The community structure differed significantly among four habitat types that were characterized by different salinity, sediment characteristics, and/or bottom elevation. For each habitat, macrozoobenthic community structure changed significantly with time, which was discriminated mostly by the lower density of polyhaline opportunistic species such as P. cf. kempi in warmer period. The salinity in the study area was much lower from May to September, mainly due to irrigation discharge from paddy fields, which seemed to be a lethal factor for the polyhaline species. C/N ratio and δ13C value of the sediment implied the accumulation of river-derived organic matters during the high river flow period. Present results showed the significant effects of fluctuating river discharge on the estuarine soft-bottom habitats, suggesting a linkage among terrestrial, riverine and estuarine ecosystems. 相似文献
139.
高光谱大气红外探测器AIRS资料云检测及晴空通道应用技术初步研究 总被引:2,自引:1,他引:1
目前GRAPES-3DVar(全球\区域同化预报系统)使用的AIRS云检测方案只能够检测出完全晴空时的视场资料,对于受到云污染的视场,所有通道资料全部被剔除。研究表明有云视场当中的云顶以上资料对数值预报的影响更加重要,研究也更加有意义。因此,文章借鉴McNally和Watts云检测方案,结合GRAPES-3DVar系统和仪器特征,建立了一种适合于GRAPES-3DVar模式的晴空通道检测方案。该方案不但可以检测出完全晴空的视场资料,同时也可以检测出有云视场当中不受云影响的云顶以上通道资料;另外,还可以求出云顶高度,判断出高、中和低云。然后,将AIRS观测资料分别用晴空视场检测方案和晴空通道检测方案进行云检测,从结果分析看,晴空视场检测方案可以检测出的晴空资料占总资料的9.14%,而晴空通道检测方案检测出的晴空资料达到了34.86%,是传统云检测方案的3.8倍,大大增加了资料的使用度。 相似文献
140.