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1.
关于中日钓鱼岛争端中"美国因素"的历史考察   总被引:4,自引:0,他引:4  
文章对中日钓鱼岛争端中的“美国因素”进行了系统考察。二战后美国的日本政策与钓鱼岛问题的产生、发展及变化有着密切联系。在冷战的国际背景下,美国政府通过托管琉球与“第27号令”将中国钓鱼岛纳入其托管之下。20世纪70年代初美国又将钓鱼岛的“施政权”作为冲绳的一部分“归还”给日本,为中日钓鱼岛争端打下“楔子”。冷战结束以来,美国政府在钓鱼岛主权归属上由“模糊中立”到当今小布什政府的“小心介入”,反映了美国政府在钓鱼岛问题立场上的变化。  相似文献   
2.
本文认为 ,在东北亚民族与历史问题研究中 ,存在将历史上的民族关系同现实的国家、民族关系直接相联系的倾向 ,由于缺乏科学的依据 ,更缺乏逻辑性和辩证性 ,将会对当代的国家与民族关系产生一定的负面影响。作者从民族体形成的规律与东北亚古民族的关系、历史疆域与现实主权疆域的关系、民族“无界”性和文化无疆域性、国家与民族形成发展的规律和特点等方面 ,对这种倾向进行了探讨。  相似文献   
3.
本共分三个部分,第一部分论述隋末唐初东突厥分化操纵中原各派势力的史事;第二部分分析东突厥对付中原各派势力的策略,指出不同时期东突厥的策论有不同的特点和变化;第三部分讨论东突厥分化操纵中原势力的几种措施,措施的特点以及形成的原因:承袭突厥的传统、借鉴隋朝的经验、利用居住突厥的胡人和华人的作用等等。最后还讨论了东突厥这些措施与中原民族的差异。  相似文献   
4.
We present a scheme to modify empirical Green's functions by attenuation considering: (1) geometrical spreading; (2) decay in high frequency; (3) regional attenuation; and (4) phase of the signal. The accelerograms computed with the proposed simulation method are compared, in time and frequency domains, with strong ground motions from subduction and intermediate-depth earthquakes recorded in Mexico. It is shown that this simple empirical Green's functions technique can synthesize both the shape and amplitude of the response spectra in the site, considering a postulated seismic source located at different distances from the original one.  相似文献   
5.
This article explores the dissipation and dispersion of torsional wave resulting from imperfection in elasticity in terms of internal friction, layer width between dissimilar homogeneous viscoelastic isotropic medium having Voigt-type viscosity. The closed forms solutions for the displacement in the upper layer and lower half space are obtained separately. The generalized torsional wave period equation is obtained and the angular frequency has been plotted against wave number for different values of relevant parametric variation and certain particular cases have been deduced. Dissipation and dispersion are analysed using two and three dimensional plots along with filled contour plots.  相似文献   
6.
The purpose of this study is to derive the attenuation relationships for PGA, PGV, and EPA parameters for areas within the seismic zones of Zagros, Alborz and Central Iran with rock and soil substructures. In order to do so, at first the available scientific data including the methods used for deriving attenuation relationships and the parameters involved have been gathered. Afterwards, all the efforts have been focused on gathering a thorough catalogue of earthquakes occurred in Iran. In this regard, a majority of the available catalogs in Iran have been gathered and corrected through different methods and finally a set of 89 earthquake events including 307 earthquake records with reliable data was chosen.

Since in order to derive the attenuation relationships it is essential to extract the parameters from the acceleration records, a great effort was placed on gathering the earthquake acceleration records of Iran. This resulted in building a database of a majority of the earthquake records up to the year of 2004. Afterwards, correction methods applicable to earthquakes records of Iran considering the type of machines used and the ground type were examined which resulted in certain guidelines for correction of earthquake acceleration record data related to Iran.

In the next step the needed parameters were extracted from the earthquake acceleration record data which were consequently divided into two seismic zones of Zagros, and Alborz and Central Iran according to tectonic conditions. After examination of the parameters and choosing the most appropriate among them, the attenuation relationships were derived for such parameters.  相似文献   
7.
民俗文物与非物质文化遗产的联系   总被引:1,自引:0,他引:1  
民俗文物和非物质文化遗产关系密切,二者是你中有我,我中有你的格局。它们同属人类文化遗产。在全球经济一体化、文化多元化和强势文化不断削弱弱势文化而急需保存我们文化多样性的形势下,加强二者的保护、传承和研究,特别是二者的结合研究,对保存我们文化的多样性,将更具有现实而又深远的意义。  相似文献   
8.
Empirical approaches based on the available earthquake catalog are popular among engineers to estimate seismic hazard. The seismic activity on individual faults inferred from these approaches is associated with a large number of uncertainties, especially due to lack of data. This article proposes a mechanistic approach to quantify seismic and fault activity, thereby overcoming the difficulties in the existing empirical procedure. A finite element (FE) model for Indian Plate, with the geological ‘cratons’ is developed and subject to plate driving forces namely, the ridge push and the slab pull forces. The material properties and the thickness of both plate and cratons are obtained through inversion using the recently available Global Positioning System (GPS) data. The tectonic faults are modeled using the well-known ‘extended FE method (XFEM)’. The simulated strains at fault level are compared with the computed strain rates from the earthquake catalog. Further, the procedure to quantify fault activity is demonstrated for Gujarat, India.  相似文献   
9.
New aspects of the frequency-dependent attenuation of the seismic waves travelling from Vrancea subcrustal sources toward NW (Transylvanian Basin) and SE (Romanian Plain) are evidenced by the recent experimental data made available by the CALIXTO'99 tomography experiment. The observations validate the previous theoretical computations performed for the assessment, by means of a deterministic approach, of the seismic hazard in Romania. They reveal an essential aspect of the seismic ground motion attenuation that has important implications on the probabilistic assessment of seismic hazard from Vrancea intermediate-depth earthquakes. The attenuation toward NW is shown to be a much stronger frequency-dependent effect than the attenuation toward SE and the seismic hazard computed by the deterministic approach fits satisfactorily well the observed ground motion distribution in the low-frequency band (<1Hz). The apparent contradiction with the historically-based intensity maps arises mainly from a systematic difference in the eigenperiods (type and size) of the buildings in the intra- and extra-Carpathians regions, thus the existing macroseismic data, based on buildings of small dimensions, i.e. with high eigenfrequency (5–10 Hz), can hardly be representative of the real hazard for new and large dimension, tall buildings, with eigenfrequency above 1 Hz.  相似文献   
10.
Strong ground motion close to a fault can be expected to be very large, so its estimation is essential for human safetv. Although a few strong-motion data exist for the west Eurasian region, we proposed in a previous work [Berge-Thierry et al., 2003] an attenuation relation for spectral acceleration using strong-motion data recorded in west Eurasia (mainly in Europe) and some in the western United States: this relationship was derived for the French Safety Rule, which is applied for seismic hazard assessment at nuclear power plants. In this study, we propose a constraining of the amplitude saturation term related to the proximity of the fault, and an adding of an amplitude saturation term in the regression model. We add, to the data-set previously used to derive the west Eurasian attenuation relationship strong-motions recorded during recent large earth-quakes: the 1995 Hyogo-ken Nanbu (Kobe) event in Japan and the 1999 Kocaeli (Izmit) event in Turkey. The regression analysis, adopted from Fukushima and Tanaka [1990], is non-linear, so an iterative procedure is applied. The determined regression coefficients lead to a prediction of a peak ground acceleration of about 0.7 g for soil site conditions at a fault distance of 0.5 km. The Q coefficient deduced, from the distance coefficient is in agreement with scattering Q models. The introduction of the saturation term leads to significantly lower predictions of average spectral accelerations at short distances as compared with using the Berge-Thierry et al. [2003] empirical model.  相似文献   
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