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261.
The Melinau carbonate platform initiated during the Mid-Eocene on a rotating slice of the Rajang accretionary prism. The differential sedimentary loading enhanced a rotation of the mobile substratum and created an elongated, asymmetrical wedge-top basin. The extensional southern margin of the basin consists of a 2100–2200-m-thick section of Eocene-to-Oligocene carbonates. These thin laterally towards the northern margin of the basin, where a carbonate factory was active on a postulated underlying thrust. Backstepping and dismemberment of the carbonate system started during the latest Oligocene and deep-marine sedimentation became prevalent over the entire region during the Early Miocene.  相似文献   
262.
Field spectroradiometry of land surface objects supports remote sensing analysis, facilitates the discrimination of vegetation species, and enhances the mapping efficiency. Especially in the Mediterranean, spectral discrimination of common vegetation types, such as phrygana and maquis species, remains a challenge. Both phrygana and maquis may be used as a direct indicator for grazing management, fire history and severity, and the state of the wider ecosystem equilibrium. This study aims to investigate the capability of field spectroradiometry supporting remote sensing analysis of the land cover of a characteristic Mediterranean area. Five common Mediterranean maquis and phrygana species were examined. Spectra acquisition was performed during an intensive field campaign deployed in spring 2010, supported by a novel platform MUFSPEM@MED (Mobile Unit for Field SPEctral Measurements at the MEDiterranean) for high canopy measurements. Parametric and non-parametric statistical tests have been applied to the continuum-removed reflectance of the species in the visible to shortwave infrared spectral range. Interpretation of the results indicated distinct discrimination between the studied species at specific spectral regions. Statistically significant wavelengths were principally found in both the visible and the near infrared regions of the electromagnetic spectrum. Spectral bands in the shortwave infrared demonstrated significant discrimination features for the examined species adapted to Mediterranean drought. All in all, results confirmed the prospect for a more accurate mapping of the species spatial distribution using remote sensing imagery coupled with in situ spectral information.  相似文献   
263.
The global geospatial community is investing substantial effort in providing tools for geospatial data-quality information analysis and systematizing the criteria for geospatial data quality. The importance of these activities is increasing, especially in the last decade, which has witnessed an enormous expansion of geospatial data use in general and especially among mass users. Although geospatial data producers are striving to define and present data-quality standards to users and users increasingly need to assess the fitness for use of the data, the success of these activities is still far from what is expected or required. As a consequence, neglect or misunderstanding of data quality among users results in misuse or risks. This paper presents an aid in spatio-temporal quality evaluation through the use of spatio-temporal evaluation matrices (STEM) and the index of spatio-temporal anticipations (INSTANT) matrices. With the help of these two simple tools, geospatial data producers can systematically categorize and visualize the granularity of their spatio-temporal data, and users can present their requirements in the same way using business intelligence principles and a Web 2.0 approach. The basic principles and some examples are presented in the paper, and potential further applied research activities are briefly described.  相似文献   
264.
Smart Client架构下的移动GIS数据采集研究   总被引:1,自引:0,他引:1  
孙贵博  宋伟东  张烁 《测绘科学》2011,36(4):188-190
传统的空间数据采集方式制约着地理空间信息服务的发展,移动GIS成为可行的解决手段.通过Smart Client技术在移动GIS数据采集中的应用,创建易于部署和管理的客户端和服务器整体架构,在工作区域较大的情况下,由多客户端进行现场数据采集、修改并实时提交到GIS服务器,直接完成数据更新.新的作业流程使采集工作内、外业融...  相似文献   
265.
介绍了不同品牌GNSS接收机的一种测试方法,其中包括动态测试的技术要求、测试点位的精心挑选、严格的组织安排、详实记录了每台GNSS接收机网络连通时间、RTK固定时间、卫星的个数、PDOP值等,并对测试的数据进行处理、分析、精度评定等内容.  相似文献   
266.
Hydrographic variability on the Alabama shelf just outside of Mobile Bay, a major source of river discharge into the Gulf of Mexico, is examined using time series of water column temperature and surface and bottom salinity from a mooring site with a depth of 20 m in conjunction with a series of across-shelf CTD surveys. The time series data show variability in a range of time scales. The density variation is affected by both salinity and temperature, with its relatively strong annual signal mostly determined by temperature and its year to year variability mostly determined by salinity. Seasonal mean structures of temperature, salinity, and density show a transition from estuarine to shelf conditions in which three regions with distinct seasonal characteristics in their horizontal and vertical gradient structures are identified. Correlation analysis with the available forcing functions demonstrates the influence of Mobile Bay on the variability at the mooring site. At low frequencies, river discharge from Mobile Bay has a varying influence on salinity, which is absent during the periods with unusually low discharge. At shorter synoptic time scales, both the estuarine response to the across-shelf wind stress and the shelf response to the along-shelf wind stress are significantly correlated with temperature/salinity variability: the former becoming important for the surface layer during winter whereas the latter for the bottom layer during both winter and summer. These forcing functions are important players in determining the estuarine-shelf exchange, which in turn is found to contribute to the shelf hydrographic structure.  相似文献   
267.
利用汶川大震后在文县县城附近架设在同一地点不同高度的三个流动台获取的7次强余震的记录,通过对原始记录做零线调整并计算记录时程均方根值,研究了局部地形高差对强震地震动的影响.结果表明,局部孤突地形对地震动加速度有明显的放大作用,在进行山区建筑选场和城镇规划时必须充分考虑局部地形的放大作用和影响.  相似文献   
268.
朱治国  李杰  刘代芹 《内陆地震》2011,25(3):263-268
利用南天山流动重力网2009~2011年的测量资料,研究了乌恰两次Ms5.1地震前后重力场的时空动态演化特征.研究表明,在两次乌恰Ms5.1地震前后,重力场变化表现出“活跃—平静—活跃”特征,两次地震发生在重力场异常上升和下降变化过程中,且震中位置处于重力变化高梯度带且靠近“0”等值线附近.  相似文献   
269.
在对微软新一代智能嵌入式平台Windows Mobile 6.5研究的基础上,针对目前广泛采用的PDA与智能全站仪联合作业技术特点,以Visual studio 2008为开发平台,采用多线程技术,实现了PDA与智能全站仪的双向通讯。  相似文献   
270.
The influence of business schools on business practitioners is considerable. An important proportion of corporate leaders hold a degree in business administration or an MBA, if not both. In the context of climate change, this influence matters: greenhouse gas (GHG) emissions from a selection of global 500 companies approximate that of the USA and the EU15 combined. Not only do corporations have a significant climate footprint, but the impact of climate change on the business landscape is already noticeable. Yet, meeting the managerial challenges that climate change brings requires knowledge only moderately addressed in business education and scholarship today. Climate change tends to be discussed in electives - hence reaching only a fraction of students - and tends to be treated alongside a myriad of other corporate social responsibility issues. Moreover, from 1992 to 2008, only seven articles with titles containing climate change or global warming were published in the top-30 peer-reviewed management journals (this paper, see also Goodall, 2008). In this paper, by mapping the diffusion of climate change within press media and academic peer-reviewed publications, I argue that understanding the existing lag in business scholarship engagement requires a fundamental understanding of processes that either hinder or lead to the diffusion of new ideas. To do so, I present a simple yet novel approach for the quantification of climate change or global warming (CCorGW) coverage relative to population size. My results on the diffusion of the climate change idea over time show: (a) an overall increase in proportional coverage in all databases (b) tipping points around the late 1980s and circa 2005 and (c) delays in adoption between press categories. I explicate the occurrence of these tipping points as well as the existence of delays by theoretically unifying my analyses with results from previous studies under the umbrella of the diffusion of innovation paradigm. I suggest that the following key factors have contributed in slowing the diffusion within business scholarship: (a) corporate values, beliefs and operational modes (b) social structures and incentives prevailing within academia and finally (b) academia's valued research communication channels. I conclude by elaborating key recommendations to facilitate the diffusion of this idea to business scholars and other influential audiences.  相似文献   
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