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991.
Steam mining method was injecting hot steam into the borehole to heat the hydrate strata at the same time of depressurization mining,which could promote further decomposition and expand mining areas of gas hydrate. Steam heat calculation would provide the basis for the design of heating device and the choice of the field test parameters. There were piping heat loss in the process of mining. The heat transfer of steam flowing in the pipe was steady,so the heat loss could be obtained easily by formula calculation. The power of stratum heating should be determined by numerical simulation for the process of heating was dynamic and the equations were usually nonlinear. The selected mining conditions were 500-millimeter mining radius,10 centigrade mining temperature and 180 centigrade steam temperature. Heat loss and best heating power,obtained by formula calculation and numerical simulation,were 21. 35 W/m and 20 kW. 相似文献
992.
Web-based Geographical Information Systems (GIS) are excellent tools within interdisciplinary and multi-national geoscience
projects to exchange and visualize project data. The web-based GIS presented in this paper was designed for the paleolimnological
project ‘High-resolution CONTINENTal paleoclimate record in Lake Baikal’ (CONTINENT) (Lake Baikal, Siberia, Russia) to allow
the interactive handling of spatial data. The GIS database combines project data (core positions, sample positions, thematic
maps) with auxiliary spatial data sets that were downloaded from freely available data sources on the world wide web. The
reliability of the external data was evaluated and suitable new spatial datasets were processed according to the scientific
questions of the project. GIS analysis of the data was used to assist studies on sediment provenance in Lake Baikal, or to
help answer questions such as whether the visualization of present-day vegetation distribution and pollen distribution supports
the conclusions derived from palynological analyses. The refined geodata are returned back to the scientific community by
using online data publication portals. Data were made citeable by assigning persistent identifiers (DOI) and were published
through the German National Library for Science and Technology (TIB Hannover, Hannover, Germany). 相似文献
993.
Integration of reflection seismic and sediment grain-size data from Lake Khubsugul (Northern Mongolia): a reply to Prokopenko and Kendall 总被引:1,自引:0,他引:1
Prokopenko and Kendall (J Paleolimnol doi:, 2008) criticise the work presented in Fedotov et al. (J Paleolimnol 39:335–348, 2008), and instead propose an alternative
interpretation for the grain-size evolution recorded in the KDP-01 core, retrieved from the central part of Lake Khubsugul.
Their interpretation is based (i) on a seismic-stratigraphic re-interpretation of sparker seismic profile khub012 (which they
copied from Fedotov et al. (EOS Trans 87:246–250, 2006)), (ii) on the presupposition that changes in lake level are the dominant
control on facies distribution in Lake Khubsugul, and (iii) on the invalidation of our age-depth model. In this reply to their
comment, we demonstrate that they interpreted seismic artefacts and geometries caused by changes in profile orientation as
true stratigraphic features and that the lake-level reconstruction they derive from this interpretation is therefore incorrect.
We also demonstrate that their grain-size predictions, which they consider to be predominantly driven by changes in lake level,
are inconsistent with the measured sulphate concentration, which is a demonstrated proxy of lake level in Lake Khubsugul,
and with the measured grain-size record. Finally, we point out that even if there would be a problem with the age-depth model,
this problem would not affect the part of the sedimentary sequence discussed in Fedotov et al. (J Paleolimnol 39:335–348,
2008). 相似文献
994.
雷达成像的波长、入射角、地面分辨率等参数严重影响着SAR差分干涉测量地面沉降的监测能力和精度,论文通过理论推导和矿区实际沉降差分干涉相位模拟,从监测到的最大沉降梯度和沉降量、保相能力、对微小沉降的敏感程度等方面对L和 C波段雷达干涉数据的矿区地面沉降监测能力进行分析;精化双轨D-InSAR数据处理的流程、方法和相应参数,使用ALOS PALSAR和ENVISAT ASAR数据获取济宁某矿区2009年12月到2010年02月期间更为精确的矿区地面沉降结果,并对沉降结果进行详细比较和系统分析.理论推导、相位模拟和真实数据实验都表明,相对于C波段的雷达干涉数据而言,L波段雷达干涉数据具有较强的保相能力,能够更好地降低失相干和相位不连续性的影响,更容易监测到沉降梯度和沉降量较大的矿区地面沉降,但对微小矿区地面沉降的敏感程度较低. 相似文献
995.
996.
997.
基于可达性与数据场的长三角经济区空间场能 总被引:1,自引:0,他引:1
空间场能是区域发展"龙头"借助区域联系通道带动外围地区发展的抽象表达,可有效刻画区域发展格局与空间差异。借助ArcGIS软件平台,采用栅格成本加权距离法、k阶数据场等模型,综合测度了长三角经济区区域可达性与空间场能,并揭示了该区域空间场能的空间格局与演变特征。研究表明:①2000年以来,长三角经济区中心城市取得了长足发展,且总体倾于均衡发展;②区域可达性条件不断改善,3 h时间圈的平均通达距离由2000年的81km提高到2008年的122 km;③区域空间场能显著增长且空间分异性显著,分布结构由单核“Z”字型向“多极”网络状形态转变;④长三角经济区空间场能分布格局可适度划分为高场能区、较高场能区、一般场能区、较低场能区、低场能区等5大类型,并呈现出圈层状特征与"两极分化"特征。 相似文献
998.
国家主体功能区空间型监测评价指标体系 总被引:3,自引:1,他引:2
对国家主体功能区开展监测和评估是掌握主体功能区规划落实情况、动态监管主体功能区运行状态的基本途径。本研究首先提出了国家主体功能区空间型监测评价指标体系概念,继而分析了指标遴选原则,即体现国家主体功能区核心功能、具备较强空间展示能力、满足管理基本需要,以及指标的可操作性、综合性与独立性等要求。在此基础上,建立了包括9个指标组和60个具体指标的体系框架。具体为:监测评价指标组包括资源、环境、生态、自然灾害、经济、人口社会、政策、交通和主体功能区运行等9个指标组;每个指标组内包含若干个可操作的具体指标。进而,还讨论了空间型监测评价指标体系的完备性与实用性、指标数据的获取方法、指标数据的空间化处理与表达等关键问题。 相似文献
999.
Spatial pattern and regional types of rural settlements in Xuzhou City, Jiangsu Province, China 总被引:4,自引:1,他引:3
This paper principally focuses on the morphological differences,spatial pattern and regional types of rural settlements in Xuzhou City of Jiangsu Province in China.Using satellite images of Xuzhou City taken in 2007 and 2008 and models of exploratory spatial data analysis(ESDA) and spatial metrics,the paper conducts a quantitative analysis of the morphological pattern of rural settlements,and finds significant characteristics.First,rural settlements in Xuzhou City are significantly agglomerated in terms of their spatial distribution;meanwhile,there is significant variation in the geographical density distribution.Second,the scale of rural settlements in Xuzhou City is larger than the average in Jiangsu Province,and the histogram of the scale data is more even and more like a gamma distribution.There are a significant high-value cluster in the scale distribution,and local negative correlation between the scale and density distribution of rural settlements in Xuzhou City.Third,the morphology of rural settlements in Xuzhou City shows relative regularity with good connection and integrity,but the spatial variation of the morphology is anisotropic.Finally,according to the characteristics of density,scale,and form of rural settlements,the rural settlements of Xuzhou City are divided into three types:A high-density and point-scattered type,a low-density and cluster-like type and a mass-like and sparse type.The research findings could be used as the scientific foundation for rural planning and community rebuilding,particularly in less-developed areas. 相似文献
1000.
半球成像方法可广泛应用于植被结构参数及冠层光合有效辐射测量等领域。高逼真度虚拟森林环境的半球成像方法模拟及验证可用于定量评估半球成像方法测量精度及地面验证研究。但高逼真度虚拟森林环境下半球成像方法模拟面临场景复杂度高、面片数巨大、模拟效率低等难题。首先,论文以高逼真度虚拟森林环境构建原理建立了不同林分密度、树木分布模式、场景大小及树木种类等特征的虚拟森林环境库;然后,在采用光线跟踪算法开展半球成像方法模拟时,对比分析了4种数据结构分割平面搜索方法,即空间中分法、对象中分法、启发式排序法和启发式BIN分区法,结果表明,启发式排序法性能最佳;最后,以高逼真度虚拟森林环境库,对比分析了传统方法、Kdtree、BVH、Octree 4种数据结构方案组织、管理单树几何模型及虚拟森林场景两级数据集效率,并选择场景节点遍历数、单树几何模型节点遍历数、单树几何模型遍历数、面片遍历数及平均计算时间等参数作为衡量数据结构组织方案性能的定量化指标,研究发现Kdtree数据结构方案较其他3种数据结构方案更为优越,因此,其可作为高逼真度虚拟森林环境库的半球成像方法模拟之首选。 相似文献