Integration and Sharing of Geo-spatial Data Based on Data Engine

Through analyzing the principle of data sharing in the database system, this paper discusses the principle and method for integrating and sharing GIS data by data engine, introduces a way to achieve the high integration and sharing of GIS data on the basis of VCT in VC , and provides the method for uniting VCT into RDBMS in order to implement a spatial database with object-oriented data model.     

Petrology, geochemistry and isotopic ages of eclogites from the Dulan UHPM Terrane, the North Qaidam, NW China

The Dulan eclogite–gneiss region is located in the eastern part of the North Qaidam eclogite belt, NW China. Widespread evidence demonstrates that this region is a typical ultrahigh-pressure (UHP) metamorphic terrane. Eclogites occur as lenses or layers in both granitic and pelitic gneisses. Two distinguished sub-belts can be recognized and differ in mineralogy, petrology and geochemistry. The North Dulan Belt (NDB) has tholeiitic protoliths with high TiO₂ and lower Al₂O₃ and MgO contents. REE patterns and trace element contents resemble those of N-type and E-type MORB. In contrast, eclogites in the South Dulan Belt (SDB) are of island arc protoliths with low TiO₂, high Al₂O₃ and show LREE-enriched and HFSE-depleted patterns. Sm–Nd isotope analyses give isochron ages of 458–497 Ma for eclogite-facies metamorphism for the two sub-belts. The ages are similar to those of Yuka and Altun eclogites in the western extension of the North Qaidam-Altun eclogite belt. The Dulan UHP metamorphic terrane, together with several other recently recognized eclogite-bearing terrenes within the North Qaidam-Altun HP-UHP belt, constitute the key to the understanding of the tectonic evolution of the northern Tibetan Plateau. The entire UHP belt extends for more than 1000 km from the Dulan UHP terrane in the southeast to the Altun eclogite–gneiss terrane in the west. This super-belt marks an early Paleozoic continental collision zone between the Qaidam Massif and the Qilian Massif.     

APPLICATION OF SOME MECHANICAL CONCEPTS TO STRUCTURAL GEOLOGY

This paper discusses some mechanical concepts that have been largely applied to structural geology and tectonics, and addresses the problems and misunderstandings in use of these mechanical terms. The purpose is to stimulate the interests for structural geologists in using the mechanical principles and methods correctly to solve the geodynamic problems.     

广西异常暴雨天气事件之异常指数初探

对广西异常暴雨天气事件之“异常指数”的设置进行了初步探讨，提出暴雨天气事件中过程日最大暴雨范围，过程持续时间，过程强降雨，特强降雨发生范围等四项异常分指数，然后统计同一过程分指数之和，得总指数，在此基础上分别选出了4－10月各月广西异常暴雨天气事件。     

自然与农田状态下照度计测光的偏差分析

根据色度基本原理，推导并计算了不同天气类型下照度的换算因数，并在不同天气类型下，对自然光和小麦群体不同高度透光情况进行了测定，将照度计实测照度换算出的辐射强度与实测辐射强度进行对比。结果表明：①前两种照度计可以在1、2级日光状况下用于太阳辐射测定而在3、4级日光状况下误差较大。②在作物田中，实测照度换算为辐射光量子数时，内活动面偏差比在0.2左右，而外活动面因光斑阴影作用，偏差较大，实测时应增加重复。     

北京地区一次典型大雾天气的空气污染过程物理量分布特征

2002年11月30至12月4日，北京持续4天大雾天气，空气污染物在持续的稳定层结条件下，空气质量连续3天达5级以上。文中分析了大雾天气各主要污染物的变化特征，以及此次过程中天气形势的特点及演变，并对造成大雾日空气污染天气的物理量分布特征进行分析。结果表明：高空WNW气流、稳定性持续增加、逆温层结持续存在、低空风速较小、相对湿度大，导致局地污染物不能及时随大气扩散；1000～700hPa有弱的上升气流形成和维持，与500hPa高空下沉气流之间在低空的某层高度上形成稳定层结(逆温层)，导致大雾及重污染的形成；850hPa为暖区，850～500hPa为冷平流，有利于大雾的形成和加重。     

广东省空气质量预报系统

文章介绍了广东省气象系统开展空气质量预报的概况，包括使用的预报工具，其预报能力与业务运行的预报质量分析，以及进一步提高预报水平的一些设想。     

Simulating Temporal Fluctuations of Real Estate Development in a Cellular Automata City

This research aims to understand the source of temporal fluctuations in real estate development through simulating a cellular automata model. In this cellular automata city, investment decisions are made according to the profitability measured in a local neighbourhood. If developers think there is enough of a profit margin in a particular site, i.e. a 'niche' of investment, they will increase investment at that site. However, by increasing investment at the site, new 'niches' might be created. Therefore, the action of converging towards an equilibrium state itself paves the way towards new fluctuations. This model demonstrates the potential of using simulation to increase our understanding of real estate dynamics. The experiments suggest that locally made 'rational' decisions can lead to temporal fluctuations because of non–linearity (discrete changes/densification and local bounded information). Interestingly, the fluctuations may show the property of a temporal fractal. This requires a sufficiently sensitive process of 'niche' formation compared with a relatively large impact of additional investment. The simulation suggests that the impact should be 4 to 20 times higher than the threshold over which a niche will be formed. This condition is satisfied in most cases of real estate investment, thus suggesting a self–organised criticality in complex real estate development.     

按不同气候背景制作单站MOS预报方程

在基层业务体制的框架基本形成以后，县局在参考上级指导预报的同时，初步开展对单站数值预报模式的研究，注意中、小尺度天气的变化规律，以提高订正预报的精度。     

The Influence of Vegetation Cover on Summer Precipitation in China： a Statistical Analysis of NDVI and Climate Data

This study provides new evidence for the feedback effects of vegetation cover on summer precipitation in different regions of China by calculating immediate (same season), and one-and two-season lagged correlations between the normalized difference vegetation index (NDVI) and summer precipitation. The results show that the correlation coefficients between NDVI in spring and the previous winter and precipitation in summer are positive in most regions of China, and they show significant difference between regions. The stronger one-and two-season lagged correlations occur in the eastern arid/semi-arid region, Central China,and Southwest China out of the eight climatic regions of China, and this implies that vegetation cover change has more sensitive feedback effects on summer precipitation in the three regions. The three regions are defined as sensitive regions. Spatial analyses of correlations between spring NDVI averaged over each sensitive region and summer precipitation of 160 stations suggest that the vegetation cover strongly affects summer precipitation not only over the sensitive region itself but also over other regions, especially the downstream region.