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121.
运用SPSS和Arc GIS分析技术,从城市职能互补和水平联系两种关联机制入手,对中原经济区2004,2009,2014年城市之间相互关联特征展开研究。结果表明:(1)中原经济区各个城市之间职能互补性不强,且城市潜在的职能互补性不断减弱,多数城市趋于综合化发展,九大职能部门中仅采掘业表现出专业化发展的趋势,其他职能部门均趋于综合化发展;(2)水平联系格局以郑州和邯郸为中心,中原城市群城市之间的联系强度大于其他两类区域(中原城市群以外主体区和中原经济区非主体区),呈现出"中心-外围"的空间格局;(3)从经济因素、区位因素、政策因素3个方面对中原经济区城市相互关联格局的形成进行了分析。  相似文献   
122.
根据Flex技术体系与特点,分析了构建基于Flex的WebGIS软件的系统结构,并阐述了Flex在WebGIS设计中的优势所在。利用ESRI公司的ArcGIS API for Flex开发包采用ASP.NET后台技术,设计并实现了广州大学城交通服务WebGIS系统。结果表明,使用Flex能够有效提高WebGIS客户端的交互能力,极大地提升了交通服务管理水平与效率,但是ArcGIS API for Flex开发包仍然存在一些不足,例如前后端通讯表现不足以及查询功能较弱等。  相似文献   
123.
The aim of this study is the design and trial of a novel sparse network beamforming (NB) technique to improve earthquake location. For this purpose bulletin phase arrival time data were processed via the use of complex exponents form and then used in an optimization via grid-search to search for the maximum semblance in hypocenter space. The use of the robust semblance statistic, provides reliable location results. The NB location results for a set of test events were compared to standard iterative ISC location procedure “iscloc” and its prototype the Jeffreys maximum likelihood estimator. For this purpose a data-base of 139 reference ground-truth events was extracted from the catalog of the International Seismological Centre (ISC) (97 GT5 events, assumed earthquakes, and 42 GT0 nuclear tests). The tuned NB procedure has shown excellent location results for events with a “good” ISC location and demonstrated the large epicenter deviations have been decreased in “bad” cases. Further developments of the algorithm would include allowances for 3D earth structure and a priori site-specific information.  相似文献   
124.
根据黄海及周边地区的布格重力资料,通过解析延拓、目标场提取、任意水平方向 导数计算、离散小波变换等处理,得到各种有关断裂的信息.经过与地震层析成像结果和地 质资料的综合分析,认为黄海中央断裂带是一组“X”型交叉断裂而不仅仅是一条NW向延 伸的断裂,并提出了有关的地球物理证据.经分析认为:黄海中央断裂带的存在是造成黄海 东西两侧在地球物理场面貌、断裂分布特点与规模上有较大差异的原因之一.由于该断裂带 的存在,致使郯庐断裂带的右旋活动所产生的应力对黄海东西两侧的影响不一致,因而产生 了黄海西部重力异常等值线凌乱、密集、断裂密布但规模相对东部较小的现象.认为黄海中 央断裂带受扬子块体向中朝块体嵌入过程的影响,形成一组近SN向为锐角的“X”断裂带 ,但该断裂带具有明显多期活动的迹象,不仅与特提斯体制下块体碰撞、俯冲作用有关,也 与后期太平洋板块向欧亚板块的聚敛、俯冲作用有关.  相似文献   
125.
中国国家气象中心中期数值天气预报业务系统   总被引:1,自引:0,他引:1  
李泽椿 《气象学报》1994,52(3):297-307
中期天气预报的研究要形成日常的业务,不仅仅是气象问题,也包括相当多的工程技术上的问题。本文概括地描述中国国家气象中心建立中期数值天气预报业务系统过程中的研究与工程建设成果以及运行状况、效果检验等。  相似文献   
126.
The sensitivity of the response of a typical AUV to changes in hydrodynamic parameters is examined. The analysis is primarily performed using a computer model of an axi-symmetric vehicle typical of many AUVs in service today. The vehicle used is the Canadian Self-Contained Off-the-shelf Underwater Testbed (C-SCOUT), designed and built by graduate and work term students. The fully nonlinear computer model is based on Newton–Euler equations of motion, and uses the component build-up method to describe the excitation forces. The hydrodynamic parameters are varied in a series of simulations with the computer model; the response being analyzed for specific performance indicators.  相似文献   
127.
The Field Research Center (FRC) including five contaminated sites and a clean background area was established in Oak Ridge, Tennessee, as a part of the U.S. Department of Energy’s Natural and Accelerated Bioremediation Research (NABIR) program. This study investigates the mineralogy and mineralogical pathways of saprolite at the FRC background site to provide a fundamental basis for the remediation strategy for contaminated sites. The background site is underlain interbedded shales, siltstones, and limestones with nearly identical characteristics to the contaminated sites. Bulk samples of saprolite were collected by hand picking approximately at 1 m depth (C horizon) from the soil surface. The soil pH of 4.3 and cation exchange capacity (CEC) of 10.5 cmol/kg measured are in the range of the typical shallow depth saprolite layer in this area. Total Fe by citrate-bicarbonate-dithionate (CBD) and ammonium oxalate extractable (amorphous) were 17.6 and 0.61 g/kg, respectively. Total Mn extracted by NH2OH·HCl was 0.17 g/kg. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses indicate that quartz, illite, and microcline (K-feldspar) are the dominant minerals, occupying 95% of mineral composition. The saprolite samples analyzed have shown characteristics of oxic conditions overall, and the degrees of weathering for three sampling locations were various, most for S1 and least for S3, likely influenced either by the flow channels developed through saprolite or by seasonal fluctuation of the groundwater table. The source of the manganese oxide that observed from the site is likely to be Mn-rich muscovite in the shale or Mn-rich biotite in the blackish band in the limestone. The results such as abundant Mn and Fe contents identified encouraging prospects for conducting remediation projects in FRC sites.  相似文献   
128.
Mayflies are very rare in the British fossil record. The first nymph to be found, Schistonotorum wallisi gen. et sp. nov., is described from the non-marine Lower Cretaceous of southeast England. This Early Barremian find is from the Upper Weald Clay Formation at Smokejacks brickworks, Surrey. It is preserved as an adpression in concretionary sideritic ironstone from the upper insect bed exposed in the northeast face of the pit. The palaeoecological significance of this record is discussed.  相似文献   
129.
The thermoelastic parameters of Ca3Cr2Si3O12 uvarovite garnet were examined in situ at high pressure up to 13 GPa and high temperature up to 1100 K by synchrotron radiation energy-dispersive X-ray diffraction within a 6-6-type multi-anvil press apparatus. A least-square fitting of room T data to a third-order Birch–Murnaghan (BM3) EoS yielded K0 = 164.2 ± 0.7 GPa, V0 = 1735.9 ± 0.3 Å3 (K’0 fixed to 4.0). PVT data were fitted simultaneously by a modified HT-BM3 EoS, which gave the isothermal bulk modulus K0 = 163.6 ± 2.6 GPa, K’0 = 4.1 ± 0.5, its temperature derivative (?K0,T/?T)P = –0.014 ± 0.002 GPa K?1, and the thermal expansion coefficients a0 = 2.32 ± 0.13 ×10?5 K?1 and b0 = 2.13 ± 2.18 ×10?9 K?2 (K’0 fixed to 4.0). Our results showed that the Cr3+ enrichment in natural systems likely increases the density of ugrandite garnets, resulting in a substantial increase of mantle garnet densities in regions where Cr-rich spinel releases chromium through a metasomatic reaction.  相似文献   
130.
简要介绍了山东移动通信枢纽工程场地所处的地震环境、历史地震影响以及工程场地条件,利用地震危险性概率分析方法确定了50年超越概率为63%、10%和2%时工程场地平均土条件下的地震烈度、基岩地震动参数,并依据一维剪切波理论进行了场地地震反应分析,得到了具体的抗震设计参数。  相似文献   
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