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排序方式: 共有4237条查询结果,搜索用时 31 毫秒
981.
Shuqing HAO Hongwei HUANG Kun YIN. Department of Geotechnical Engineering Tongji University Shanghai China. College of Construction Engineering Jilin University Changchun China 《东北亚地学研究》2007,10(2):190-195
By simplifying the characters in the air reverse circulation bit interior fluid field, the authors used air dynamics and fluid mechanics to calculate the air distribution in the bit and obtained an equation of flow distribution with a unique resolution. This study will provide help for making certain the bit parameters of the bit structure effectively and study the air reverse circulation bit interior fluid field character deeply. 相似文献
982.
By simplifying the characters in the air reverse circulation bit interior fluid field, the authors used air dynamics and fluid mechanics to calculate the air distribution in the bit and obtained an equation of flow distribution with a unique resolution. This study will provide help for making certain the bit parameters of the bit structure effectively and study the air reverse circulation bit interior fluid field character deeply. 相似文献
983.
984.
确立以日蒸发量来作为描述可晾晒程度的物理量。根据日蒸发量与日最高温度、日平均相对湿度等诸多因子的相关性,进行回归计算,建立其预报方程。通过数轴凝聚,对1998、1999年常州市气象站的逐日蒸发量的变化范围并结合天空状况等因素进行分类,以此作为晾晒指数等级的标准。将方程结果与标准相对照,即可得到次日的晾晒指数等级和相应决策。 相似文献
985.
986.
This paper investigates the nonlinear prediction of monthly rainfall time series which consists of phase space con-tinuation of one-dimensional sequence, followed by least-square determination of the coefficients for the terms of the time-lag differential equation model and then fitting of the prognostic expression is made to 1951-1980 monthly rainfall datasets from Changsha station Results show that the model is likely to describe the nonlinearity of the an-nual cycle of precipitation on a monthly basis and to provide a basis for flood prevention and drought combating for the wet season. 相似文献
987.
弹性介质中密度ρ与拉梅常数λ、μ的衍射层析成像方法研究 总被引:4,自引:0,他引:4
利用接收到的纵波信息,通过解纵波方程得到介质的密度和拉梅常数分布函数.首先,在频率波数域建立了描述入射纵波信号、接收纵波信号和介质三参数扰动量之间关系的积分方程.然后,建立了关于接收信号的各频率成份的方程组.经过正反傅氏变换求解此方程组即可得到介质三参数的分布函数.最后,就跨孔观测系统进行了数值模拟成像试验。结果表明方法有效. 相似文献
988.
共炮检距二维弹性波地震剖面的偏移方法 总被引:1,自引:0,他引:1
在均匀各向同性介质的分界面上入射纵波时,除产生纵波反射P-P波外,还会产生转换横波的反射P-SV波。同样,当入射波为SV横波时,在分界面上会同时产生SV-SV反射波和SV-P反射转换波,对这种二维弹性波地震记录如何进行偏移是正在探讨的问题。为了能够处理实际地震数据,本文提出在共炮检距剖面上进行二维弹性波记录的偏移方法。具体做法是,首先用弹性波方程将两分量的地震记录分解为P-P(或SV-SV)波和P-SV(或SV-P)波,然后用我们已导出的适合于处理共炮检距剖面的叠前偏移方法对它们进行处理。用模拟数据进行的试验说明方法正确,效果良好。 相似文献
989.
990.
Given time-independent monthly mean sea temperature,numerical simulation was done of the path of the tropicalcy clone Forrest and its related physical quantity field in terms of the improved version of the σ-coordinate 10-level primitive equation model for tropical cyclones developed by the Guangzhou Institute of Marine Meteorology.Result ssuggest the similarity between the simulated and observed physical quantity fields except that the simulated path was to the right of the observed,with the deviation increasing with time.Sea and tropical cyclone,in effect,interact mutually.In an attempt to compare the results from coupling and uncoupling experiments,an oceanic mixed layer model was formulated based on experiments with sea response to cyclone and integrated in synchronous coupling with the aforementioned version of tropical cyclones,the computational domain covering the western North Pacific with the coastal configuration involved.The coupling experiment shows that the negative feedback of the interaction between sea and mature cyclone leads to weaker sea response as compared to the uncoupling case.Except for the location of the divergence core of oceanic current,the mixed layer depth and inhomogeneous distribution of sea surface temperature (SST) caused by the cyclone-core position and intensity,the values of the maximum oceanic current,departure of the mixed layer depth and SST drop were smaller in the coupling than in the uncoupling case,and so was the maximum wind near the cyclone core.The path from the coupling run is to the left of the course in the uncoupling experiment but closer to the observed one though remaining somewhat leftward.Even on a scale of less than 3 days,the effects of sea and sea-cyclone interaction on the cyclone were by no means negli-gible. 相似文献