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The post depositional thermal maturity and its related chemical changes induce the sporomorphs color alteration, which is a common useful tool in the optical microscopy of the organic matters (OM) and their pre-geochemical studies. The present contribution uses the modern available opportunity of digital technology to achieve a quantifying system technique, which includes color measurements and their possible graphic presentation. The normal digital images of sporomorphs from several ages and geological settings are used to obtain color measurements in the form of digital Red, Green and Blue triple color system (RGB). These measurements were accomplished using some software programs such as Photoshop™© or ImageJ with employing average microscope setup. The triple RGB color readings are plotted on a ternary diagram, which is divided into three fields. These fields express the maturity levels. The presented new RGB-based quantifying technique is economic and provides a simple examination for maturity, which is linked to the hydrocarbon generation. This can partially replace or walk side by side with the vitrinite reflectance microscopy. 相似文献
123.
随着“数字城市”建设的推进,地理信息系统建设进入全面发展阶段,加快基础空间数据更新频率的需求日趋强烈。如何有效的使用基础空间数据,为城市建设增砖加瓦成为政府部门关注的问题。该文主要阐述某个城市的系统方案设计、体系架构、网络架构与实现功能,为其他三维数字城市管理平台的建设提供一定的参考依据。 相似文献
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在被动型氢原子钟数字伺服电路中,使用FPGA对误差信号进行数字信号处理。设计了一种简单的低通滤波器,与传统的FIR滤波器相比,节省了FPGA的使用资源,并且性能优于传统滤波器,能够很好地应用于被动型氢钟。 相似文献
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虚拟地理环境研究进展与理论框架 总被引:3,自引:0,他引:3
阐述虚拟地理环境的形成、发展与研究现状,并从"虚拟现实技术"与"虚拟现实"的相互关系探讨虚拟地理环境基本概念.从基本思想、系统结构、在线参与者社会组织水平、与GIS/数字地球的关系等角度,分析虚拟地理环境的特征.从数据、模型、表现以及协同4个方面,讨论了虚拟地理环境系统建设的关键技术与研究前沿.尝试建立了一个虚拟地理环境基本理论初步研究框架,认为在地理哲学思想层次应该重点研究复杂性人地系统、地理虚/实关系论、地理/遥感信息本体论,在地理/地理信息科学层次需要重点研究地理认知与思维、地理相似原理、地理计算模拟;同时讨论虚拟地理环境与面向"人"的地理信息科学、基于虚拟地理环境地理科学方法论,以及可计算人地关系的相关理论问题. 相似文献
128.
The accumulation mechanism of methane hydrates has been a central issue in previous hydrate research regarding the Nankai accretionary prism, southwest of Japan. Expulsion of formation fluids is significant during the prism accretion process, and the migration of these methane-bearing fluids exerts a strong control on the accumulation of hydrates. Two types of fluid pathways, inter-granular porosity and faults, need to be evaluated to understand hydrate accumulation. Fluid migration along faults can be partly modeled by examining faulting activity. Our study modeled the accretion process by using two granular methods that approximated the geologic body as an assemblage of particles: (1) analog experiments using granular materials, and (2) a numerical simulation based on the distinct element method. The analog experiments closely reproduced the prism geometry observed in seismic profiles across the Nankai accretionary prism. Digital image correlation analysis indicated that the frontal thrust is generally active but older structures are also frequently reactivated. The numerical simulations produced prism geometries similar to those of the analog experiments. The velocity distributions of the particles showed evidence of episodic faulting and reactivation, but the internal stress field exhibited little change in the deeper part of the prism during deformation. The frequent and substantial changes in fault activity displayed by the models indicate episodic fluid flow along fault surfaces. Active frontal thrusting suggests that formation fluids generally migrate from deep within the prism to the deformation front, but may move along reactivated older faults. Inter-granular permeability also fluctuates, as it is controlled by temporal and spatial variations in the internal stress field. However, fluid flow is likely to be relatively stable in the deeper segment of the prism. 相似文献
129.
《Geoforum》2014
This article explores how standards and codes for collaboration in international higher education influence the educational space of global online education and the way it functions within the context of international development aid. Firstly the article discusses the educational space of higher education and the geography of education whereby the aim is to situate global online education within the on-going discourse on standards in higher education, international development aid, and the knowledge economy. The article then examines a qualitative case study of an Internet-based masters programme attended by students from Europe and Africa. A main focus of the empirical analysis is the students’ experience of being geographically immobile while collaborating online internationally, including how this circumstance affected their motivation and participation and the benefits of the programme. In the concluding discussion it is argued that even though online collaboration among students and educational institutions is not entirely equal, common standards created a space in which positions were challenged and practices were changed over the course of online participation. 相似文献
130.
合成孔径雷达干涉测量是一种利用SAR影像复数据的相位信息提取地面三维信息的技术,它通过获取地面目标在两幅SAR影像上的相位差值来解算该点的三维坐标。有理多项式(RPC,Rational Polynomial Coefficient)模型作为一种数学意义上的几何模型,它独立于传感器和平台,简单且具有通用性,可建立地面任意坐标与影像空间的关系。本文在RPC模型用于替代星载SAR的距离多普勒模型和星载InSAR的干涉相位方程基础上,研究 RPC模型应用于星载高分辨率InSAR影像制作DEM的可行性和精度。利用兰州COSMO-SkyMed数据和资源三号三线阵数据制作的DEM为参考数据进行实验验证,RPC模型用于InSAR技术生成的DEM,中误差为7.55米。 相似文献