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941.
Analysis on geo-effects of China’s overseas industrial parks: A case study of Cambodia Sihanoukville Special Economic Zone 总被引:1,自引:0,他引:1
China's overseas industrial parks contribute to political and economic cooperation,cultural exchange between home and host countries.Current studies mainly discuss the ef-fect of overseas industrial parks from the perspective of institutional and cultural difference,multi-scale coupling,as well as key partnerships,while little attention has been paid to the comprehensive analysis of overseas industrial parks.Based on a theoretical framework,this paper explores the overall effect of China's overseas industrial parks from the geo-effects perspective by using field interviews and a case study approach.The research shows that:(1)the geo-effects reveal the over effect of overseas industrial parks from the multiple and com-plementary dimensions of geopolitics,geo-economics,geo-society and geo-culture;(2)the Cambodia Sihanoukville Special Economic Zone,as a flagship BRI project,has produced the prominent and positive geo-effects;(3)the institutional-economic-cultural-environmental adaptability of overseas industrial parks is becoming important.Overseas industrial parks must be rooted in the politics,economy,society,and culture of host country;embedded in local social networks;balance the rights and interests of all stakeholders;and form the community of interests,community of destiny,and community of responsibility with political mutual trust,economic integration,cultural inclusiveness,and social harmony.The paper not only deepens the understanding about the overall effect of overseas industrial parks,but also provides decision support and theoretical reference for government policy makers and the overseas investment of enterprises. 相似文献
942.
海水表面温度是研究气候变化的重要参数,具有巨大的研究意义.在近海海域进行研究时对分辨率具有较高的要求.在珠江口区域,利用LANDSAT 8影像热红外波段,结合美国中等分辨率成像光谱仪(MODIS)的近红外水汽二级产品MOD05,运用Jiménez-Mu1oz提出的单通道法,优化了部分参数,建立海表温度的反演流程.为了确定可行性,将与LANDSAT 8影像同一日期的MODIS海表温度产品MOD28作为实验的对照组,利用实测数据对比验证2组数据的质量.结果表明,反演结果时空分布规律与MOD28趋近一致,均呈现为夏季西高东低而冬季西低东高,全年温度变化接近准正弦曲线,并且反演结果精度更优,具有良好的应用前景. 相似文献
943.
Ming-Jiang Zhang Hong-Bo Wang Chang-Yin Zhao Jian-Ning Xiong Dong Wei Wei Zhang Sheng-Xian Yu 《Astrophysics and Space Science》2018,363(8):175
Taking the re-entry object CZ-3B R/B (COSPAR identifier 2012-018D, NORAD catalog number 38253) as an example, retrieval of atmospheric mass densities in lower thermosphere below 200 km from its rebuilt precise orbit is studied in this paper. Two methodologies, i.e. analytical and numerical methods, are adopted in the retrieval. Basic principles of these two methodologies are briefly introduced. Based on the short-arc sparse observational data accumulated in the high accuracy re-entry prediction, orbit determinations of re-entry object CZ-3B R/B are performed sectionally, and then its precise orbit is rebuilt. According to the orbit theory, the variation of orbital semi-major axis of re-entry object CZ-3B R/B induced by atmospheric drag perturbation only is derived from the rebuilt precise orbit. In the derivation of secular change of the orbital semi-major axis of re-entry object CZ-3B R/B induced by atmospheric drag perturbation only, the time-span is set as one minute tentatively. And then retrieval results of atmospheric mass densities in lower thermosphere below 200 km by analytical and numerical methods are presented, as well as their bias deviations from the calculated results of the NRLMSISE-00 empirical model of the atmosphere. Setting bias deviation bands, the corresponding ‘confidence coefficients’ of the retrieved atmospheric mass densities with respect to the model values are given. Average bias deviations of the retrieved atmospheric mass densities by analytical and numerical methods from the model values are also calculated respectively. On the whole, the retrieved atmospheric mass densities by numerical method approach to the model values more closely; the differences between the retrieved results and the model values are relatively smaller at the peaks of atmospheric mass densities than the other places. 相似文献
944.
为明确高海况下海况等级对无人水下航行器横摇运动的影响,得出满足某型无人水下航行器安全回收的海况条件,对高海况下无人水下航行器的横摇运动进行分析。运用频率响应法,分别在4级、5级和6级海况下,根据海浪谱密度函数和该型航行器的横摇频率响应函数,求得其横摇运动谱密度函数。再运用公式推导,得到其横摇运动的时域函数。使用MATLAB仿真软件对该型航行器进行横摇运动仿真,得到3种海况条件下,其横摇运动的时域函数图像,并验证仿真结果的准确性。仿真结论:高海况下的海况等级对无人水下航行器的横摇幅度有较大影响,满足其安全回收的海况条件为5级海况。 相似文献
945.
提出了基于判定准则的海洋环境下目标关系识别方法。通过HBACA算法查找或识别不同元素关系能力强的特性,提取目标信息数据的关系,之后在信息数据关系中计算每个信息节点的点度中心度、紧致中心度和节点活跃度,根据信息数据在目标事件中的重要或关键程度,将信息数据划分为关键目标信息、重要目标信息和一般目标信息。仿真结果显示:能够明确地获得关键的信息数据坐标,并与其所处事件的重要程度能够匹配,同时相关信息数据的关系非常明显,很容易提炼出所处目标事件中重要目标信息数据之间的关联。 相似文献
946.
We used binary octahedrons to investigate the dynamical behaviors of binary asteroid systems. The mutual potential of the binary polyhedron method is derived from the fourth order to the sixth order. The irregular shapes, relative orbits, attitude angles, as well as the angular velocities of the binary asteroid system are included in the model. We investigated the relative trajectory of the secondary relative to the primary, the total angular momentum and total energy of the system, the three-axis attitude angular velocity of the binary system, as well as the angular momentum of the two components. The relative errors of the total angular momentum and the total energy indicate that the calculation has a high precision. It is found that the influence of the orbital and attitude motion of the primary from the gravitational force of the secondary is obvious. This study is useful in understanding the complicated dynamical behaviors of the binary asteroid systems discovered in our Solar system. 相似文献
947.
N. V. Narizhnaya M. Yu. Khovrichev A. A. Apetyan D. A. Bikulova A. P. Ershova I. A. Balyaev A. M. Kulikova K. I. Os’kina L. A. Maksimova 《Solar System Research》2018,52(4):312-319
We present the results of observations of the Galilean moons of Jupiter carried out at the Normal Astrograph of the Pulkovo Observatory in 2016?2017. We obtained 761 positions of the Galilean moons of Jupiter in the system of the Gaia DR1 catalog (ICRF, J2000.0) and 854 differential coordinates of the satellites relative to each other. The mean errors in the satellites’ normal places and the corresponding root-mean-square deviations are εα = 0.0020′′, εδ = 0.0027′′, σα = 0.0546′′, and σδ = 0.0757′′. The equatorial coordinates of the moons are compared to the motion theories of planets and satellites. On average, the (O–C) residuals in the both coordinates relative to the motion theories are less than 0.031′′. The best agreement with observations is achieved by a combination of the EPM2015 and V. Lainey-V.2.0|V1.1 motion theories, which yields the average (O–C) residuals of approximately 0.02″. Peculiarities in the behavior of the (O–C) residuals and error values in Ganymede have been noticed. 相似文献
948.
M. A. Ivanov M. Ya. Marov A. T. Basilevsky Yu. A. Kostitsyn 《Solar System Research》2018,52(7):570-577
The article reviews the results of photo geological study of the lunar surface in terms of selection of most favorable landing sites from the point of view of science merit and safety for the Luna—Glob mission descent module. 相似文献
949.
950.
Wenhao Yu 《Marine Geodesy》2018,41(1):68-85
Sounding acts as the main feature in a digital nautical chart as it describes the concerned marine topography for the safety of navigation. Unlike the geometry-oriented selection of point feature, the generalization of soundings for chart compiling is expected to be context-oriented, which means bathymetry complexity variations across the study region should be preserved in the sounding selection process. However, such variations are not explicitly accessible to automated systems. This paper proposes an approach that effectively analyzes and measures bathymetry complexity from sounding data, with a focus on topography variations among different regions. The presented approach first divides the exploring region into several subregions, by adopting techniques of computational geometry and graph theory. Then, the approach quantitatively measures the bathymetry complexity of the subregions from grid-based digital terrain model. Finally, a composite bathymetry complexity index integrating aspects of steepness and depth variation is developed to guide the operation of sounding selection in different subregions. Generally, when seafloor is rugged with steep slopes, the number of soundings is high. While in flatter areas, a smaller amount of soundings is retained. The potential of our approach is demonstrated by an application to a real data set. 相似文献