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991.
烟台市"121"气象信息产业经营策略 总被引:2,自引:0,他引:2
总结分析了2000~2002年烟台市"121"气象信息产业在服务内容、广告宣传、内部管理等方面的具体做法,提出了"121"品牌专业化、人性化的经营策略。 相似文献
992.
1. Introduction Human activities including social and economic de-velopments, are closely related to the change of theweather and climate system. Since the beginning oftime, weather and climate, which are the general termsfor the entire range of phenom… 相似文献
993.
LAI Shaocong ZHANG Guowei PEI Xianzhi & YANG HaifengKey Laboratory of Continental Dynamics Ministry of Education Department of Geology Northwest University Xi''''an China Correspondence should be addressed to Lai Shaocong 《中国科学D辑(英文版)》2004,(2)
Detailed studies indicate that Kangxian-Pipasi-Nanping tectonic zone is a complicated melange zone which includes many tectonic slabs of different origins. Ophiolite (MORB-type basalt), oceanic island tholeiite and alkaline basalt have been identified. Moreover, this tectonic melange zone is eastward connected with the Mianlue suture zone. The deformation characteristics, consisting components and volcanic rock geochemical features for the Kangxian-Pipasi-Nanping tectonic melange zone are much similar to those of the Mianlue suture zone and Deerni ophiolite. Therefore, the Kangxian-Pipasi-Nanping tectonic melange zone should be the westward extension part of the Mianlue suture zone. It indicates that the Mianlue suture zone had extended to the Nanping area. 相似文献
994.
SHEN Ji Lü Houyuan WANG Sumin CHEN Shiyue YANG Xiangdong WU Yanhong & ZHU Zhaoyu .Nanjing Institute of Geography Limnology Chinese Academy of Sciences Nanjing China .Institute of Geology Geophysics Chinese Academy of Sciences Beijing China .Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Correspondence should be addressed to Shen Ji 《中国科学D辑(英文版)》2004,(11)
The uplift of the Tibetan Plateau is the most im-portant event in the Cenozoic Era. It has been provedthat the rising Plateau is of great significance to globalatmospheric circulation and climate change. It has alsoinfluenced the transmission and balance of the globalmatter and energy[1—3]. The uplift of the Plateau is un-doubtedly true, but there have long been argumentsabout the process and mode of the Plateau uplift. Didthe Plateau rise as a whole or partly? Did it rise oncefor all or … 相似文献
995.
Illustration
All the data in this catalog are chosen from the “Preliminary Seismological Report of Chinese Seismic Stations“(Its abbreviation is“Monthly Report“). The catalog includes the events of M≥4.7 in and near China and M≥6 all over the world. The“Monthly Report“is monthly compiled by the Ninth Section of Institute of Geophysics, China Earthquake Administration.…… 相似文献
996.
小波变换的时频分析和奇异性检测特性,使得其在非稳态信号处理中有不可抵挡的优势,本文用已知的合成信号对这两个特性进行了分析和说明. 对几次地震前的形变时间序列资料(定点潮汐形变观测、GPS观测)作了小波变换. 结果发现:地震前约4个月左右,震中周围的几个定点形变台站都接收到周期为几天到十几天的异常信号;而地震前震中周围的几个GPS观测站均同时接收到周期为3个月到半年左右的异常信号,不同的地震异常出现的时间不一样. 这些同时出现在多个台站或观测站的同频段的异常信号是可能的地震前兆. 相似文献
997.
通过研究打桩公式法和应力波动法(如CASE法),提出单次冲击能量及P-S曲线测桩法:用重锤或小型火箭筒一次冲击桩顶,用桩顶附近的检波器记录振波图和检测静、动位移. 通过实测冲击能(总能量)转换系数、波动和振动各自消耗的能量等各物理量,测定计算单桩竖向承载力. 利用振波图计算力(P)与位移(S)动态关系曲线,确定屈服点,并利用静载荷试验检验动测结果和确定动静P-S曲线的相关常数,进而确定与承载力相应的沉降量. 而且,可由PS曲线的形态判定桩身成型质量. 相似文献
998.
据1985年台湾海峡西部海域综合调查资料,报道了该海域表层沉积物中MnO,MgO,Fe_2O_3,Al_2O_3,CaO和TiO_2的含量分布特征,讨论了各金属氧化物之间及其与沉积物类型的关系。 相似文献
999.
The sea ice is idealized as an elastic-brittle material. When an ice sheet moves toward a structure, the dynamic in-teraction between ice and the structure is analyzed by the DDA (Discontinuous Deformation Analysis) approach, where the ice sheet and the structure are considered as assemblages of blocky masses. This has the advantages that the whole process of collision between the ice and structure can be shown visually vvith a series of pictures. Meanwhile, the dynamic response of the structure at each time step after the bumping of the ice against the structure is calculated. And with the aid of inverse analysis developed by the authors, the time history of the resultant ice force exerting on the structure is evaluated. A numerical example shows that the proposed approach is suitable to the simulation of the ice-breaking process and reasonable result of ice force acting on the structure can be obtained. 相似文献
1000.
The generation of low frequency waves by a single or double wave groups incident upon two plane beaches with the slope of 1/40 and 1/100 is investigated experimentally and numerically. A new type of wave maker signal is used to generate the groups, allowing the bound long wave (set-down) to be included in the group. The experiments show that the low frequency wave is generated during breaking and propagation to the shoreline of the wave group. This process of generation and propagation of low frequency waves is simulated numerically by solving the short-wave averaged mass and momentum conservation equations. The computed and measured results are in good agreement. The mechanism of generation of low frequency waves in the surf zone is examined and discussed. 相似文献