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161.
1 The Raising of the Problem 1.1 The development of the international container traffic At the end of the 1930s, the developed countries began to develop container traffic, following the first one established on land which prevailed marine transport after expansion in the 1970s and the 1980s. Then many junction ports had special container berths constructed throughout the world and all main transportation lines were containerized. With the development of the world trade and increase of the pr… 相似文献
162.
MA Haitao 《地理学报(英文版)》2022,32(11):2170-2188
China’s Belt and Road Initiative(BRI) presents the world with a new era of inclusive globalization, which will shape urbanization patterns globally. This study considered the launch of BRI as a quasi-experiment, where we evaluated the BRI’s impact on urbanization by way of difference-in-differences(DID) and propensity score matching(PSM) methods. The results showed that the BRI exerted a significantly negative effect on urbanization in its first three years. Its positive effect emerged from the ... 相似文献
163.
Urban Construction Land Suitability Evaluation Based on Improved Multi-criteria Evaluation Based on GIS (MCE-GIS): Case of New Hefei City,China 总被引:2,自引:0,他引:2
Urban construction land suitability evaluation (UCLSE) is a complex system engineering and the basis for rational use of the limited urban land resources in China. It has an important practical value on urban construction land use planning and management from the angle of methodology. As a widely used technique, traditional multi-criteria evaluation based on GIS (MCE-GIS), is not suitable for UCLSE. This study develops an improved MCE-GIS method which could be more suitable for UCLSE based on urban complex ecological system theory and the summary of the shortcomings of traditional MCE-GIS. The improvements include three aspects: a composite evaluation index system rather than natural indexes alone, an index weight calculated by using fuzzy Analytic Hierarchy Process (AHP) method rather than the common AHP method, and the integrated overlay rule, which includes selecting the minimum value, weighted linear combination (WLC) and simple summation. The main advantage of this improved technique is that it can make UCLSE more comprehensive, more operational and more reasonable. It can provide a scientific basis for decision making in the planning and management of urban construction land use. The improved MCE-GIS system has been adopted in the New Hefei City, Anhui Province, China. Based on the results of UCLSE in New Hefei, three functional areas including construction-appropriate areas, construction-restricted areas and construction-forbidden areas could be worked out, in which 36.90% of the total study area could be developed as urban construction land and the remaining 63.10% should be protected as reserves land or as ecological land. Furthermore, the results can orovide scientific decision suooort for spatial planning and eco-environment nrotection in New Hefei. 相似文献
164.
1INTRODUCTIONWiththerecentmodernizationandurbanizationofChi-na,urbanareashavegreatlyincreased, andgiantbuild-ings,especiallythosetallerthan100m,havebeendomi-nantincities,whichhave resultedinthegreatincreaseintheproportionofbuilding'sexternalsurfacetototalurbanarea.Thedifferencesofthermalpropertiesmain-lyinducedbysolarradiationbetweenbuilding'sexter-nalsurfacesareobviousfordifferentexposures,whichcaninevitablyinfluencethedistributionsofairtempera-turenearby,eventheverticaldistributionsofurb… 相似文献
165.
SUN Tong SUN Dong-ya WANG Xie-kang MA Qiang GOURBESVILLE Philippe NOHARA Daisuke 《山地科学学报》2022,(6):1738-1747
With the increasing of extreme rainfall frequency, landslides accompanied by mudslides often lead to serious casualties and property damage. On 3rd July 2021, a debris flow occurred in Izu Mountain area, Shizuoka County, Japan, and then resulted in 26 deaths and 131 houses destroyed, where houses were mainly built along the banks of the creek. In order to analyse the landslide state and distribution, a two-dimensional debris flow dynamic model(Massflow) was selected to simulate the process of th... 相似文献
166.
The strength deterioration mechanism of soil polluted by heavy metals plays a crucial role in the research of mine site pollution. In this study, an unconfined compressive strength(UCS) test, a p H test, a scanning electron microscopy(SEM) test, a low filed nuclear magnetic resonance(NMR) test, and an X-ray diffraction(XRD) test were conducted on Zn2+,Cu2+ and the combination of Zn2+ and Cu2+ polluted soil to investigate the strength deterioration mech... 相似文献
167.
<正>The Bangong Lake-Nujiang River metallogenic belt is located between the Qiangtang Block and Lhasa Block,and the Duolong ore concentration area is located in the western section of the Bangong Lake-Nujiang River metallogenic belt.Till now,several large and super large copper-gold deposits,such as Duobuza,Bolong, 相似文献
168.
正1 Introduction As one of the major zooplanktonic organisms in the Ordovician and Silurian marine ecosystems,graptolites played a unique role in the GOBE (Great Ordovician Biodiversification Event) and underwent a considerable variation of diversities both in lifestyle and in speciation through the Ordovician (Sadler et al.,2011;Cooper et al.,2014).Graptolites are among the early 相似文献
169.
170.
NING Chuanxiang MA Zhongliang JIANG Zhenxue SU Siyuan LI Tingwei ZHENG Lunju WANG Guozhen LI Fengxun 《《地质学报》英文版》2020,94(2):352-363
To reveal the effect of shale reservoir characteristics on the movability of shale oil and its action mechanism in the lower third member of the Shahejie Formation(Es3l), samples with different features were selected and analyzed using N2 adsorption, high-pressure mercury injection capillary pressure(MICP), nuclear magnetic resonance(NMR), high-speed centrifugation, and displacement image techniques. The results show that shale pore structure characteristics control shale oil movability directly. Movable oil saturation has a positive relationship with pore volume for radius > 2 μm, as larger pores often have higher movable oil saturation, indicating that movable oil is present in relatively larger pores. The main reasons for this are as follows. The relatively smaller pores often have oil-wetting properties because of organic matter, which has an unfavorable effect on the flow of oil, while the relatively larger pores are often wetted by water, which is helpful to shale oil movability. The rich surface provided by the relatively smaller pores is beneficial to the adsorption of immovable oil. Meanwhile, the relatively larger pores create significant pore volume for movable oil. Moreover, the larger pores often have good pore connectivity. Pores and fractures are interconnected to form a complex fracture network, which provides a good permeability channel for shale oil flow. The smaller pores are mostly distributed separately;thus, they are not conducive to the flow of shale oil. The mineral composition and fabric macroscopically affect the movability of shale oil. Calcite plays an active role in shale oil movability by increasing the brittleness of shale and is more likely to form micro-cracks under the same stress background. Clay does not utilize shale oil flow because of its large specific surface area and its block effect. The bedding structure increases the large-scale storage space and improves the connectivity of pores at different scales, which is conducive to the movability of shale oil. 相似文献