基于微博平台的中国城市网络信息不对称关系研究

网络信息空间的空间关系及信息流研究为信息化影响下的地理空间演变研究奠定基础。借助微博这一新兴网络信息传播平台获取中国城市间网络信息联系数据,采用流分析方法呈现城市间网络信息联系的空间格局。研究发现:中国城市网络信息关系呈现出"一超多强"的空间极化不对称格局。网络空间不对称格局与地理距离、经济社会发展水平存在密切关联性,表现为:城市对外网络信息总不对称度与其经济社会发展水平的相对一致性;经济社会发展差距对城市间网络信息不对称程度影响的距离衰减性;城市间网络信息不对称程度与经济社会发展差距的相对一致性;东、中、西部三大地区间网络信息不对称关系与经济发展梯度的相对一致性。     

Cretaceous aquifers in North Carolina: analysis of safe yield based on historical data

The Cretaceous aquifers underlying the central part of the North Carolina Coastal Plain are used extensively as the preferred source of water for municipalities, industries, and agriculture. Regional decline in head in the middle parts of the system (the Upper Cape Fear and Black Creek aquifers) began in the late 1950s to early 1960s. The trends in head during the 1960s, together with data on land subsidence, were analyzed to demonstrate the value of using early data, in conjunction with conceptual models, before collecting additional data. The sources of withdrawals from the Cretaceous aquifers identified in the conceptual model are: (1) movement of water (recharge) across confining beds, (2) reduction in natural discharge, (3) release of water from aquifer storage, (4) drainage of water from fine-grained lenses in aquifers and confining beds, and (5) release of water resulting from advance of the salt-water front. Estimates of the amounts derived from each of these sources resulted in a reduction of the estimated safe yield of the Cretaceous aquifers in the 2,486-mi² (6,439-km²) area of the central Coastal Plain from 75 mgd (million gallons per day) (284,000 m³/day) to less than 5 mgd (19,000 m³/day). Electronic Publication     

河川径流的灰色拓扑预测研究——以新疆阿克苏河为例

根据阿克苏河流域内出山口水文站1957～2006年的径流实测资料,利用数理统计、Mann-Kendall非参数趋势检验及小波分析等方法对径流年际变化特征进行了分析。研究发现,阿克苏河年径流量具有相对稳定且振荡上升的趋势,年际变化小;  径流序列在1993年发生突变,径流量呈现出显著增加趋势,且通过了α=0.05的显著性水平检验;  丰、枯水周期变化存在着25a左右的主周期,丰水年发生在20世纪90年代后期,且大量连续出现,最长持续时间达7年,枯水年多以连续2年的形式出现,平水年年数占52％。运用灰色拓扑预测方法对突变前后两个径流时间序列分别进行了模拟和预测,模拟结果的平均相对误差仅为12.06％,且位于同一突变区间的精度达97.7％,预测未来几年阿克苏河年径流量存在上升趋势,但趋势不显著。     

Behavioral Diversity and Complexity Indicated by Metazoan Traces at a Topological Level since Proterozoic

INTRODUCTIONTrace fossils,which reflect the behavior and morphologyof the m etazoan in this paper,exhibit tremendous diversityand complexity of morphology at a Euclidean geom etrical lev-el,fitting into a relatively small number of morphological andethologic patterns at a topological level.Although no clearlyformulated guidelines are present in ichnology as to the majorcomposition of a useful and meaningful ichnotaxon and to therank of classification(Pickerill,1994) at which m orphologica…     

The influence of Zihe Stream on the groundwater resources of the Dawu well field and on the discharge at the Heiwang iron mine, Zibo City area, Shandong Province, China

 The Dawu well field, one of the largest in China, supplies most of the water for the Zibo City urban area in Shandong Province. The field yields 522,400–535,400 m³/d from an aquifer in fractured karstic Middle Ordovician carbonate rocks. Much of the recharge to the aquifer is leakage of surface water from Zihe Stream, the major drainage in the area. Installation of the Taihe Reservoir in 1972 severely reduced the downstream flow in Zihe Stream, resulting in a marked reduction in the water table in the Dawu field. Since 1994, following the installation of a recharge station on Zihe Stream upstream from the well field that injects water from the Taihe Reservoir into the stream, the groundwater resources of the field have recovered. An average of 61.2×10³ m³/d of groundwater, mostly from the Ordovician aquifer, is pumped from the Heiwang iron mine, an open pit in the bed of Zihe Stream below the Taihe Reservoir. A stepwise regression equation, used to evaluate the role of discharge from the reservoir into the stream, confirms that reservoir water is one of the major sources of groundwater in the mine. Received, May 1998 / Revised, May 1999 / Accepted, June 1999     

MapX支持下道路网络拓扑结构构建方法

对于一个实用的车载导航系统,最优路径规划是其必备的十分重要的功能,而道路网络拓扑结构的构建又是最优路径规划的基础.对基于MapInfo的道路网络拓扑结构的构建算法进行了初步的研究,设计了表达道路网络拓扑结构的数据结构,并在MapX控件支持下在VC 6.0环境下完成了该算法的实现.     

An anisotropic Model for Structured Soils: Part I: Theory

The paper presents an incremental plasticity constitutive Model for Structured Soils (MSS–2) to describe the effects of structure (stress history and bonding) on the mechanical behaviour of cohesive soils. Such effects are high initial stiffness, dilatancy and peak strength, their appreciable reduction upon strain-induced de-structuring and the evolution of material anisotropy. The proposed model advances present practice in incremental elasto-plasticity for structured soils by incorporating: (a) distorted ellipsoids, rotated with respect to the isotropic axis, for the Structure Strength Envelope (bounding surface) and the Plastic Yield Envelope (yield surface) to describe the evolution of structure and anisotropy, (b) an Intrinsic Compressibility Framework and a corresponding Intrinsic Strength Envelope which represents a lower bound of the Structure Strength Envelope and is used as reference locus for the structureless material, (c) an improved damage mechanism to model structure degradation by plastic strains and (d) a non-associated flow rule controlled by structure. The proposed model is modular, its features can be activated simultaneously or selectively, and the 3-D tensorial formulation facilitates direct implementation in finite elements codes.     

The protection of groundwater dependent ecosystems in Otago, New Zealand

Surface waters (streams, rivers, and wetlands) are the most important groundwater dependent ecosystems (GDEs) in Otago, New Zealand. Pumping wells in the vicinity can deplete water in the GDE. In Otago, most of the surface water resources are allocated and a method, which would assist in the implementation of water management policy, is needed to acknowledge the strong hydraulic link between surface and shallow groundwater. A simplified method has been developed which derives a numerical relationship between the bore pumping rate and the distance between the bore and surface water body beyond which depletion is considered insignificant. A range of GDE depletion scenarios are examined at various combinations of hydraulic parameters to find a minimum distance for a given pumping rate, at which 90% of the modelled surface water depletion scenarios become less than a threshold GDE depletion after a specified time. A buffer zone, based on the minimum distance is placed around GDEs, and groundwater abstraction rights within the buffer are subject to stricter rules. Applicants wishing to abstract from bores within the buffer zone will need to address the environmental impact of the proposed activity on the GDE.     

Hydrodynamic convergence of hydropressured and geopressured zones, Central Texas, Gulf of Mexico Basin, USA

Freshwater moving downdip in the Carrizo–Wilcox aquifer, Central Texas, USA, and saltwater and hydrocarbons moving updip from a geopressured zone come together in a groundwater convergence zone, marked by (1) a hydraulic-gradient reversal, (2) “updip” oil fields, and (3) the downdip limit of potable water beyond which there is a marked increase in salinity. Data combined from groundwater-supply and petroleum-extraction industries document the interface between the hydropressured and geopressured zones. The hydraulic-head gradient updip of the convergence zone is 0.001 to 0.002, directed toward the coast; farther downdip it is ?0.02 to ?0.04, directed inland. Salinity increases from <400 mg/L near the outcrop, to ～3,000 mg/L at the downdip limit of potable water, to >100,000 mg/L in the geopressured zone. Upward-directed flow paths probably predominate in the convergence zone. The convergence zone in the study area lies within only 30–50 km of the outcrop because updip extensional faulting offsets permeable aquifer units against low-permeability strata and restricts the downdip flux of recharged water. The major elements of the convergence zone may have been in place since the Miocene development of circulation in the updip coastal aquifer following incision of river valleys and lowering of base level.     

Changing relationships between Religion, the State, and Society in Russia

This paper first traces the major changes in the relationship between the (Orthodox) Church and State in the different Russian polities, using Madeley’s framework of historic mono-confessional blocs and multi-confessional belts. Second, it outlines the recent tendencies and characteristic features of church–state relations in today’s Russia. Third, using data from sociological surveys, it analyses the current dominant popular perceptions and societal attitudes towards religion and the State, including religious freedom. Being part of the historic mono-confessional Orthodox bloc, the different Russian polities produced different models of church–state relations: from a symphony of religious and political powers, through a forced nationalization of the Orthodox Church (Russian Empire from the époque of Peter the Great until revolution of 1917), and forced secularisation (during the Soviet Union), to a return of mutual support of (Orthodox) Church and State despite a formal (constitutional) separation in Putin’s Russia.