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991.
992.
圆弧形有水河谷场地对平面P波的散射 总被引:1,自引:0,他引:1
利用波函数展开法,在频域内给出了圆弧形充水河谷对平面P波散射问题的解析。并分析了入射波波长、入射角对充水河谷地形地面运动的影响。 相似文献
993.
994.
The influence of China-Europe Railway Express on the production system of enterprises: A case study of TCL Poland Plant 总被引:1,自引:0,他引:1
The implementation of the Belt and Road Initiative and the increasing frequency of the China-Europe Railway Express(CER Express)have brought new improvement to the production system of enterprises along the Belt and Road regions.On the basis of summa-rizing the evolution of production system of enterprises,this paper takes TCL Poland Plant as an example to conduct an in-depth study on the characteristics of the plant's current produc-tion system and its differences from the original production system,and analyzes the impact of the CER Express on its current production system.Some conclusions can be drawn as follows.(1)CER Express had a great impact on the production system of TCL Poland Plant,which is mainly manifested in the following aspects.First,the transport of raw materials by CER Express improves the time efficiency and shortens the whole supply chain.Second,CER Express acts as a"moving inventory",which realizes the flexibility of raw material in-ventory and"zero inventory"effect based on the punctual transport.Third,the time and in-ventory effects brought by CER Express speed up the response to European market.The comprehensive benefits brought by CER Express lead to a more punctual and lean produc-tion system,meet the diversified needs of consumers on account of product quality and di-versification,and improve ability to expand European market.(2)On the basis of abandoning the original"Rigid Mass Production"system,we argue that TCL Poland Plant formed a unique production system—"Global Fluid Just-in-Time"which absorbed the essence of Toyota Pro-duction System based on the punctual transnational transportation of CER Express.(3)The differences between the current and the original production systems of TCL Poland Plant are mainly focused on the following aspects:the difference of transport and storage mode of raw materials,and the changes of production line,production mode and quality inspection or-ganization,etc. 相似文献
995.
建平烧锅营子金矿流体包裹体特征研究 总被引:2,自引:0,他引:2
对烧锅营子金矿石英流体包裹体进行了详细研究。流体包裹体均一温度为280℃~320℃、爆裂温度为240℃~290℃。成矿流体富含Na+、K+、Au+、Cl-、H2O和CO2。金以AuCl-形式存在于成矿流体中。CO2含量与金矿化强度呈正相关。成矿流体pH值为5.31~5.53。成矿流体呈弱酸性、低盐度、低密度、相对氧化环境。 相似文献
996.
997.
采用基于质能平衡的积雪过程模型—雪热力模型(Snow Thermal Model, SNTHERM.89)来描述和模拟2008年中国甘肃省黑河实验冰沟流域的积雪过程与积雪特性参数,并将模型模拟的雪水当量与高级微波扫描辐射计(AMSR-E)的雪水当量产品进行了对比。模型验证结果表明,SNTHERM模型能准确模拟黑河冰沟流域的积雪变化过程和积雪特性,对积雪的演变特征作出合理的描述,表明SNTHERM在中国黑河冰沟流域有较好的适用性。对SNTHERM模型进行不同驱动气象参数和初始输入参数的敏感性分析的结果表明,积雪特性参数对辐射通量最敏感;各积雪特性参数对各自的初始输入比较敏感,密度则对初始输入的雪深、密度和颗粒大小都比较敏感,表明在需要准确模拟密度的情况下以及进行雪水当量同化工作时,初始输入的雪层深度、密度和颗粒都必须比较准确。 相似文献
998.
This paper presents an analytical solution for the dynamic behavior of both the platform and tethers in the tension leg platform system when the platform system is subjected to the wave-induced surge motion and the flow-induced drag motion. Along with the analysis the coupling problem of a two dimensional tension leg platform interacting with a monochromatic linear wave train in an inviscid and incompressible fluid is being considered. The scattering problem and radiation problem are first solved independently and then combined together to resolve for all unknowns. The dynamic behavior of the platform and tethers was further solved based on these solutions. The material property and the dimensional effect for the tether incorporated in the tension leg platform system are both taken into account in the analytical analysis. Corresponding to the variation of material properties and tether dimensions, it was found that the dynamic behavior of both the tether of tension leg platform and the platform itself is closely related to the material property and the dimension of the tether. 相似文献
999.
L. Zühlsdorff V. Spieß C. Hübscher H. Villinger A. Rosenberger 《International Journal of Earth Sciences》2000,88(4):655-667
A high-resolution seismic survey was carried out at the accretionary prism on the continental slope off Vancouver Island,
Canada. Two GI-Gun data sets with different source frequency ranges of 50–150 and 100–500 Hz were combined with 4 kHz narrow-beam
echosounding data (Parasound). The data allow spatial correlation between a gas hydrate bottom simulating reflector (BSR)
and distinct areas of high near-sea-floor reflectivity. An integrated interpretation of the multi-frequency data set provides
insight into the regional distribution of tectonically induced fluid migration and gas hydrate formation in the vicinity of
ODP Leg 146 Sites 889 and 890. The BSR at the base of the gas hydrate stability field is observed within accreted and deformed
sediments, but appears to be absent within bedded slope basin deposits. It is suggested that these basin deposits inhibit
vertical fluid flow and prevent the formation of a BSR, whereas the hydraulic conductivity of the accreted sediments is sufficiently
high to allow for pervasive gas migration. An elevation of the BSR beneath the flanks of a topographic high is interpreted
as an indicator for local upflow of warm fluids along permeable pathways within outcropping accreted sediments. Parasound
data reveal discontinuous zones of high reflectivity at or directly beneath the sea floor, which may indicate local cementation
of surface sediments. In combination with GI-Gun data, the occurrence of these reflective areas can be related to the location
of slope sedimentary basins acting as hydraulic seals. It is proposed that the seals sometimes fail along faults extending
beneath the BSR, leading to focused upflow of methane-bearing fluid and the formation of carbonate pavements at the sea floor.
Received: 9 November 1998 / Accepted: 6 April 1999 相似文献
1000.
为了深入研究流体对岩石中弹性波速度和衰减的影响,必须考虑到流体的分布和粘性。引入气体包裹体模型来研究粘性流体的分布对松散介质中P波速度和衰减的影响,用气泡平均半径来描述流体分布的不均匀性,计算了不同气泡半径和频率下P波速度和衰减随饱和度变化的曲线,并与有效流体模型作了比较,由于流体喷流的存在会使Gassmann方程在高频下不适用,用干燥和饱和流体的P波、S波速度修正了理论曲线。测量了玻璃微珠中不同水饱和度下高频P波的速度和衰减,并尝试用峰值频率来计算衰减。此方法求出的Q和频谱比法求出的Q在干燥或饱和水时基本相同,随饱和度的变化规律也基本一致,但衰减峰的大小有差异。根据实测值得似事经修正的波速和衰减理论曲线从而估算出气泡平均半径,认为P波速度和衰减不仅与饱和度有关而且也与介质内部气体-液体压力平衡有关。 相似文献