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1.
无缝空间数据中心概念模型及其技术体系 总被引：2，自引：0，他引：2
随着空间数据中心技术在国土资源等领域地逐渐成熟,开拓出一套具有自身特色的空间数据集成管理与开发利用模式,是一种新型的分布式地理信息系统(geographic information system,GIS)应用模型.然而,空间数据集成与整合利用、增量更新问题以及不同厂家的功能共享与合作开发仍然是亟待解决的问题.在空间数据中心技术的基础上,引入分布式异构空间数据无缝集成技术,建立了数据无缝、功能无缝和应用无缝3个层次的无缝空间数据中心概念模型,并讨论了其技术体系. 相似文献
2.
县(市)级土地利用数据库系统的构建和实现 总被引：10，自引：0，他引：10
手工管理土地资料的方法, 数据更新周期慢, 综合利用率低, 查询统计复杂, 已经不能满足当前社会经济发展的需要.根据新一轮国土资源大调查中县(市) 级土地利用数据库标准和县(市) 级土地利用数据库建设技术规范2个标准的要求, 利用地理信息系统技术和空间数据库管理技术, 阐述了土地利用数据采集的技术路线, 空间数据的组织和分层管理模式, 空间数据库建立的工艺流程, 以及系统的运行环境要求和功能实现. 相似文献
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地质资料是地质工作服务经济社会发展的主要载体.建设地质资料数据中心,核心是实现数据到信息、知识的转化与集成,再对外提供多元化的社会化应用服务.本文对上海市地质资料数据中心的总体框架作了介绍,并从中心IT基础体系、数据资源体系、应用服务体系、信息安全体系、标准规范体系、管理体系等方面阐述了地质资料数据中心建设和运营的关键技术和具体措施,以发挥示范作用,促进国土资源信息化和数字城市建设. 相似文献
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市县两级电子政务系统是集国土资源数据管理、业务应用、安全保障等功能的全国国土资源电子政务体系的底层和基础。本文通过对湖南省国土资源市县级电子政务现状的简要介绍,对电子政务的三大核心平台：运行平台、搭建支撑平台和数据中心管理平台的技术架构和使用的部分关键技术进行了解析。 相似文献
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地理信息系统是太原市国土资源电子政务平台的业务核心系统,以ArcGIS为基础地理框架,通过近年来规范、严格的数据标准体系建设,不断深入的数据挖掘应用,海量空间数据存储和调用效率的优化,为地政、矿政的图文审批、数据资源的共享．辅助审核提供了高效率。 相似文献
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从国土资源“一张图”数据中心亟待解决的问题入手,结合山东省国土资源数据中心建设实际,从国土资源数据建设的宏观和规划层面,探讨国土资源“一张图”数据中心的定位、与国土资源各业务系统的关系和科学合理的建设步骤等方面问题,为构建覆盖“横向到边、纵向到底、联动更新、资源共享”的国土资源“一张图”数据中心提供理论支撑。 相似文献
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为了解决分布式地质图空间数据库之间的数据共享和一致性维护问题,在MAPGIS7 .0面向地理实体的空间数据模型的基础上,根据地质图空间数据组织和分布的特点设计了一种“横向网格、纵向多级”的分布式多级服务器组网方案,结合该方案提出了一种以地质空间要素类为单位,面向服务的数据交换策略.该策略在国家地质调查空间数据库管理系统中的应用表明:以要素类为基本数据交换单位可以有效地维护分布式地质数据的空间、拓扑和语义的一致性;以服务的方式操作使数据交换能够跨平台、跨操作系统以及适合异构数据库.实践证明,这种策略是适合于分布式地质图空间数据库的一体化组织与管理的. 相似文献
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如何提高地质图空间数据库信息交换体系的可扩展性和互操作能力是这一领域中的研究热点.首先研究了ISO/OGC空间信息共享的规范和标准, 并建立了具有服务能力的空间信息集成模块, 在此基础上研究具有一致性的空间信息共享与服务体系, 形成独立于软件、适用于地质空间信息互操作的表达模式, 提供一个可用于异构和分布式体系下的数据描述机制, 使得应用管理地质空间数据成为可能.提出了以地理置标语言(geography markup language, GML) 模型为框架, 给出一种地质空间信息交换的机制.针对地学应用需求, 提出了专业应用数据的模式, 为地质空间信息交换提供了一种可行的方法. 相似文献
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Water renewal estimates for aquaculture developments in the Richibucto estuary,Canada 总被引：1，自引：0，他引：1
Water renewal in semi-enclosed coastal areas is crucial for the supply of oxygen and seston and for the removal of organic
loadings from finfish or shellfish aquaculture sites. Water renewal depends on hydrodynamic processes and can have a complex
spatial distribution due to irregular topographic features. This study describes some physical oceanography observations gathered
in the Richibucto estuary, New Brunswick, Canada, and provides an estimate of the spatial distribution of water renewal in
the North Arm, a location in the estuary where the largest American oyster (Crassostrea virginica) aquaculture operation in eastern Canada is located. The estuary changes from a well mixed estuary to a partially stratified
estuary depending on runoff conditions. Tides are mixed but mainly diurnal due to the nearby presence of the second M2 amphidromic point in the Gulf of St. Lawrence. Tidal amplitudes vary from 0.3 to 0.6 m and show a slight increase some 35
km upstream. Currents in the main channel can reach over 0.60 m s−1 during ebb and 0.3 m s−1 during flood, with a slack water period of approximately 8 h. Low frequency sea level fluctuations have a range of 0.5 m
at the mouth and are coherent within the estuary. Hydrodynamic and advection-dispersion models are used to calculate the spatial
distribution of the local renewal time (LRT) in the North Arm for high and low freshwater discharge conditions, using the
dissolved tracer method. Results show that the LRT varies from less than 5 d at the downstream end of the North Arm to over
100 d further upstream. When averaged over the entire North Arm, the integral renewal time (IRT) is estimated to vary only
from 8 to 21 d depending on the season. The LRT and IRT estimates are major improvements over conventional renewal estimates
using tidal prism methods. 相似文献
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Christian Ferrarin Luca Zaggia Elio Paschini Tommaso Scirocco Giuliano Lorenzetti Marco Bajo Pierluigi Penna Matteo Francavilla Raffaele D’Adamo Stefano Guerzoni 《Estuaries and Coasts》2014,37(1):79-93
A multidisciplinary approach that combines field measurements, artificial neural networks, water balance analyses and hydrodynamic modelling was developed to investigate the water budget and renewal capacity of semi-closed coastal systems. The method was applied to the Lesina Lagoon, a micro-tidal lagoon in the southern Adriatic Sea (Italy). Surface water flux between the lagoon and the sea was determined by neural network prediction and used as input in the analysis. Strong seasonal variations in the water budget equation were predicted. Fresh water inputs estimated by the water balance analysis were used as forcing by a calibrated finite element model to describe the water circulation and transport time scale of the lagoon’s surface waters. The model highlighted the spatial heterogeneity of the renewal behaviour of the system, with a strong east–west water renewal time gradient. Knowledge of spatial distribution of water renewal times is crucial for understanding the lagoon’s renewal capacity and explaining the high spatial variability of the biogeochemistry of the Lesina Lagoon. 相似文献
13.
基于GIS和背景数据知识的空间数据库遥感更新研究--以安徽省1:5万土地利用现状数据库为例 总被引：2，自引：0，他引：2
随着我国社会经济快速发展,地理空间数据库的快速动态更新是迫切需要解决的问题.采用遥感TM图像为数据源,基于GIS对数据操作、管理、显示等良好功能以及背景数据知识,通过地学知识发现和综合建立各地类解译标志,直接在空间背景数据库基础上进行多要素修改变更,具有时间省、工作量小、效率和精度高特点,成功地实现了1:5万土地利用现状数据库一级和部分二级地类2000年时相的快速、准确更新.该方法也可应用于其他相应比例尺地理空间数据库的更新. 相似文献
14.
Kee-Bom Nahm 《GeoJournal》1999,49(3):289-299
In recent years, central Seoul has been experiencing a dynamic transformation. In the process of reorganization of the urban
industrial structure including tertiarization and quaternarization of the economic base of Seoul, business services are growing
very rapidly and large scale urban renewal projects are quickly implemented. Downtown office activities become a nucleus for
economic performance of Seoul and high-rise office buildings steer the landscape transformation of central Seoul. Even though
there appears to exist some evidence that office districts have dispersed to several subcenters, major office activities are
still concentrated in central Seoul. This paper redefines office industry in a narrow sense comprising only relevant economic
sectors and office buildings as office activity-functioning units. It then explores the industrial networking and territorial
specialization of office activities focusing on the dual process of concentration and dispersion in Seoul. The changing characteristics
of the downtown linkages of office activities in this post-industrial era transforms the spatial economy of central Seoul
into a more flexible and volatile system, while territorial concentration of power and control functions are fortified at
the same time. Finally, the paper addresses the development of manufacturing- tertiary-quaternary industrial complexes, which
can be regarded as emerging industrial clusters, producing the cultural economy of urban space and images for clients and
customers, in relation to urban competitiveness and territorial specialization of large metropolitan areas.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Ned P. Smith 《Estuaries and Coasts》1993,16(4):739-746
The flushing of Florida’s Indian River Lagoon is investigated as a response to tidal and low-frequency lagoon-shelf exchanges in the presence of freshwater gains and losses. A one-dimensional computer model uses the continuity equation to convert water-level variations into both advective transport within the lagoon and lagoon-shelf exchanges. The model also incorporates transport by longitudinal diffusion. Flushing is quantified by calculating the 50% renewal time, R50, for each of 16 segments. R50 is calculated for tidal exchanges enhanced by 0–30 cm nontidal fluctuations in coastal sea level, then for a range of rainfall rates. In both series of simulations, results suggest that in the northern sub-basin, R50 increases dramatically with distance from the inlet due to relatively weak tidal and nontidal exchanges. A 50% renewal occurs in about one tidal cycle just inside Sebastian Inlet; at the northern end of the northern sub-basin, R50 is over 230 d, and only coastal sea-level variations on the order of 30 cm and/or dry season rainfall rates decrease R50 to less than 1 yr. R50 is 1 wk or less throughout the central and southern sub-basins, where lagoon-shelf exchanges occur through two inlets. Simulations involving seasonal variations in precipitation and evaporation indicate that maximum and minimum rates of freshwater input lead minimum and maximum salinities by time periods on the order of 2–3 wk for the lagoon as a whole and in the northern sub-basin. The central and southern sub-basins respond in 1–2 wk. 相似文献
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Patrick A. Pitts 《Estuaries and Coasts》1989,12(2):92-97
Current and wind data collected during a 223-d study period from early June 1983 through early January 1984 are used to document net upwind return flow over seasonal time scales in the Indian River Lagoon near Sebastian Inlet on the Atlantic Coast of central Florida. Spectral analysis of wind and current meter data suggests that wind forcing accounts for the majority of nontidal flow. The two time series are highly coherent at periodicities of 2,3–3.5, 4, and 6 d. The serial correlation coefficient of ?0.49 is significant at the 99.9% confidence level. Historical water level and wind data recorded simultaneously at Sebastian Inlet and Eau Gallie, 34.5 km to the north, suggest that longitudinal pressure gradients are established in response to seasonal wind patterns. The upwind near-bottom return flow is interpreted as a response to the seasonal set up of the longitudinal pressure gradients. The study documents the importance of windstress in forcing low-frequency transport over seasonal time scales. 相似文献
18.
Nicholas Dines 《GeoJournal》2002,58(2-3):177-188
This article examines the relationship between immigration and urban renewal in Naples during the 1990s through the conflicting representations and uses of Piazza Garibaldi, a large piazza located in front of the city's central railway station. As well as the hub of the city's public transport network, since the mid-1980s this piazza has been the multifunctional space for a number of immigrant groups. Re-envisioned as the `gateway' to the city's regenerated centro storico (historic centre) during the 1990s, the piazza became a focus of public debates on security, tourism and, in particular, immigration. I examine how these issues intersected with political discourses about a renewed sense of citizenship in redefining the piazza as a strategic but problematic public space. Drawing on ethnographic fieldwork and analysis of local newspaper reports, the article looks at the ways in which the piazza has been appropriated by different immigrant groups for social and economic purposes, and how, at the same time, they have been excluded from discourses about a `new' Naples. 相似文献
19.
Spatial and temporal study of nitrate concentration in groundwater by means of coregionalization 总被引：1，自引：0，他引：1
Spatial and temporal behavior of hydrochemical parameters in groundwater can be studied using tools provided by geostatistics.
The cross-variogram can be used to measure the spatial increments between observations at two given times as a function of
distance (spatial structure). Taking into account the existence of such a spatial structure, two different data sets (sampled
at two different times), representing concentrations of the same hydrochemical parameter, can be analyzed by cokriging in
order to reduce the uncertainty of the estimation. In particular, if one of the two data sets is a subset of the other (that
is, an undersampled set), cokriging allows us to study the spatial distribution of the hydrochemical parameter at that time,
while also considering the statistical characteristics of the full data set established at a different time.
This paper presents an application of cokriging by using temporal subsets to study the spatial distribution of nitrate concentration
in the aquifer of the Lucca Plain, central Italy. Three data sets of nitrate concentration in groundwater were collected during
three different periods in 1991. The first set was from 47 wells, but the second and the third are undersampled and represent
28 and 27 wells, respectively. Comparing the result of cokriging with ordinary kriging showed an improvement of the uncertainty
in terms of reducing the estimation variance. The application of cokriging to the undersampled data sets reduced the uncertainty
in estimating nitrate concentration and at the same time decreased the cost of the field sampling and laboratory analysis.
Received: 23 July 1997 · Accepted: 31 March 1998 相似文献
20.
Elisha Efrat 《GeoJournal》1986,13(4):401-411
The objectives of the paper are to indicate, on a national and regional level, the areas of geographical inequality in Israel, which create economic and social gaps in the development of the country. Geographical inequality in this study has been analyzed through eleven different criteria, relevant to economic and social welfare situations, as: distance from the nearest big city, road accessibility, rate of population density, natural economic potential, spatial security, distance from the central plain and centers of economic activity, climatic index of discomfort, topography, oldness of the settlements in the surroundings, etc. Each element of inequality has been plotted on a map indicating its quantitative values,on the basis of square units, comprising 25 km2 each. A weighting of all the squares according to qualitative criteria enabled to prepare a comprehensive and compilative map with isolines showing the different spatial and inequality degrees.The map which has been elaborated from the data shows districts and localities in a range of different spatial degrees of deprivation. The history of settlement in Israel since the end of the 19th century, the planning guidelines since the establishment of the State in 1948, and the main geographic features of the country are the reasons of regional disparities. 相似文献