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71.
John Turnbull Thomson,Fellow of the Royal Geographical Society: An early New Zealand geographer 下载免费PDF全文
Michael Roche 《New Zealand geographer》2016,72(1):3-13
John Turnbull Thomson is more known in New Zealand for his work as Chief Surveyor of Otago Province (1856–1876) and first Surveyor General of New Zealand (1877–1879). He was also a Fellow of the Royal Geographical Society of London from 1848 until his death in 1884. Thomson was an important and early self‐declared ‘does’ of geographer in New Zealand, prior to the establishment of university geography in 1937. Thomson's contribution included survey and mapping but he also gave public lectures on geography and contributed to debates about glaciation. 相似文献
72.
地震动记录的合理选取对预测结构响应有着重要的作用。本文通过对风雨操场建筑混合结构的抗震性能分析,提出了一种对水平及竖向地震动频谱特性均进行控制的改进选波方法。为了评价不同选波方法的可靠性和有效性,根据初选条件选取55组三向地震动记录,并以55组地震动的统计反应谱作为目标反应谱,以55组记录计算的结构响应均值作为"预测值",通过与单周期点和双频段选波方法的计算结果对比,分析表明:改进选波方法计算的结构基底剪力、柱顶位移、支座位移和网架竖向位移的相对误差和变异系数均小于前两种选波方法,其计算结果更加可靠有效。 相似文献
73.
利用EDS/MODIS交叉定标FY1D/VIRR可见光-近红外通道 总被引:7,自引:0,他引:7
以EOS/MODIS的星上定标结果为标准,采用交叉定标方法标定FY1D/VIRR的可见光-近红外通道。先获得两个传感器的配对通道,然后利用6S模式计算出他们的匹配因子,根据EOS/MODIS的观测敦煌辐射校正场扫描计数值和星上定标结果以及它和FY1D/VIRR的匹配因子计算出FY1D/VIRR同时观测敦煌辐射校正场时的表观辐亮度和表观反射率,最后将得到的表观辐亮度和表观反射率与FY1D/VIRR观测敦煌辐射校正场的计数值进行比较,就得到了FY1D/VIRR通道的绝对定标系数。将本次定标结果与敦煌场地定标试验的定标结果比较,定标结果一致性较好,并可用于对发射前定标偏差进行校正。 相似文献
74.
由于地物与地形模型分开建模等现实原因,地物模型与地形模型集成的时候会出现不匹配问题。因此,本文通过分析地物与地形之间的空间依存关系,针对地物独立于地形和地物依赖于地形两种情况分别提出了地物模型与地形模型的匹配方案,并着重研究地物依赖于地形时的匹配方案与算法。 相似文献
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77.
我国气象科技期刊发展与作用 总被引:9,自引:0,他引:9
在对历史资料研究的基础上,对气象科技期刊的发展历程与作用进行了回顾及评述,并对目前气象科技期刊的现状及存在的问题做了简要分析。 相似文献
78.
利用断裂活动过程中留下的各种地质标记研究断裂发育史是比较困难的 ,已有的研究方法主要可归纳出七种 ,都存在局限性。岩层离距图法是以地震剖面为基础 ,将穿过断裂的各剖面上的标志层投影到沿断裂走向的铅垂面上 ,得到多组标志层的垂向断距数据 ,然后用下部各标志层的断距减去最上部标志层的断距 ,并作多轮次计算 ,直到最后的断距差近似为零或仅剩一个非零标志层。每一轮次计算代表一个活动期次 ,如果出现负值 ,则表示有构造反转。对松辽盆地敖古拉断裂作了实例计算 ,结果为该断裂发育经历了三个正断活动期和一个逆断活动期 ,与盆地区域性活动有些差别。岩层离距图法比起其他已有方法 ,可靠程度大大提高 相似文献
79.
After an earthquake, earthquake emergency response and rescue are important ways to mitigate earthquake-induced losses. Various earthquake emergency maps can provide effective references and guidance to those actions. Currently, related studies include the investigation on symbols of emergency maps, remote sensing emergency mapping and GIS-based mapping methods. However, the existing studies overlook the characteristics of rapidity, dynamicity and variety of presentation methods in making earthquake emergency maps. In this paper, a map template matching method is used to quickly make earthquake emergency maps considering their characteristics. We take investigations on the service objects(users)of the earthquake emergency maps to understand the needs of making earthquake emergency maps. The audience theory in mass media field and map information transmission theory are adopted to classify the users of the earthquake emergency maps into four categories: earthquake emergency commanders, technical staffs for decision-making, earthquake emergency rescuers, and the public. The components of different types of users are described and then their diverse demands in earthquake emergency maps are analyzed, such as the needs of on-field disaster information maps, earthquake information maps, physical geography and social economic maps. Following those needs, we introduce the representation methods of the earthquake emergency maps according to their formats(vector or raster)and contents, such as point symbolization method, kilometer grid method, line symbolization method and range method. Then, we study the rapid plotting method of earthquake emergency map based on map template matching method. The core steps of the method include: 1)before earthquake, the templates of different earthquake emergency maps are designed, prepared and connect the earthquake emergency features with their related spatial database. The map layout and map elements are stored in the templates. 2)After earthquake, the earthquake emergency features will be generated from seismic models(such as attenuation model of earthquake magnitude and seismic intensity)or the information obtained from field investigation. 3)Corresponding earthquake emergency map template is selected in accordance with the generated seismic features. And the features are used to update related features inside the selected template. 4)Minor adjustments are made such as to the map scale and some map annotations to finally generate the formal earthquake emergency map. Architecture of template system of the earthquake emergency maps is designed, including map user level, map template level, template layer level and map element level. Regrading to the architecture, the general map template of earthquake emergency is presented which includes four main regions: title region, main picture region, auxiliary region and annotation region. The main picture region is the essential, which lays geographic background maps and earthquake emergency features. Finally, an earthquake emergency mapping system is developed. Based on the system, a case study is presented, which demonstrates making a simulated seismic intensity influence map. From three aspects, the case presents the application of the template-matching method including: generating earthquake emergency features, substituting the features inside the template with the generated features, and revising map annotations. Therefore, the map template matching method is verified so that it can be used to quickly generate various earthquake emergency maps. 相似文献
80.
Environmental effects on the reproduction and fecundity of the introduced calcareous sponge Paraleucilla magna in Rio de Janeiro,Brazil 下载免费PDF全文
The calcareous sponge Paraleucilla magna (Porifera, Calcarea) has been the subject of several studies in the last decade. It was first described along the Brazilian coast, where it is considered cryptogenic, and was subsequently found in the Mediterranean, where it is considered invasive. The wide artificial distribution of this species allows us to compare different aspects of the biology of an introduced species in different locations. Here, we analysed the effects of selected environmental parameters on the reproductive dynamics of P. magna in Rio de Janeiro (Brazil) over 18 months and compared our results with those obtained for the same species in the Mediterranean Sea. Specimens were collected monthly and analysed through histological methods. The density of reproductive elements in each month was calculated, and the effects of environmental parameters (photoperiod, precipitation, temperature, phytoplankton and bacterioplankton) were analysed using a regression tree analysis. Paraleucilla magna was reproductive throughout the study period. The densities of the reproductive elements (oocytes, embryos and larvae) showed no seasonality, and this species presented one of the highest reproductive efforts documented to date in the phylum Porifera (99.0 oocytes · mm?3; 89.0 embryos · mm?3; 319.0 larvae · mm?3). The main environmental parameters related to the reproduction of P. magna were temperature, photoperiod and bacterioplankton. Temperature was the main driver associated with the densities of oocytes and embryos, while bacterioplankton was the main driver of larvae (positive relationships). In Rio de Janeiro, larvae were present and continuously released. This strategy is different from that observed in the Mediterranean, where a larger larval output was observed but only during the summer months. Our results show that P. magna is a species with a strong invasive potential, considering its high and continuous reproductive effort. This high fecundity stimulated by high temperatures may be a key factor contributing to the growth of P. magna populations and its invasion of new areas. 相似文献