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101.
硫酸盐渍土在多次冻融循环时的盐胀累加规律 总被引:10,自引:3,他引:7
通过室内模拟试验,研究了硫酸盐渍土在历经多次冻融循环时的盐胀累加规律,得出了盐胀累加的不同类型,给出了累加盐胀率与循环次烽之间的关系式,进一步揭示了盐胀累加的 和影响因素。 相似文献
102.
103.
针对带乘性噪声广义系统,提出1种在线性最小方差意义下的状态最优估计算法.首先,采用标准分解将系统变换为2个子系统;其次,通过估计子系统的状态,获得原系统的状态最优滤波.同时,算法还给出了动态噪声与量测噪声的估计.仿真结果表明了该算法的有效性. 相似文献
104.
研究了军曹鱼(Rachycentron canadum)早期阶段的生长和摄食特性。结果表明:1~29日龄间,全长与日龄之间呈指数函数相关:y=3.6922e0.0995x(R=0.9913);体重与日龄间呈指数函数相关:y=0.0002e0.276x(R=0.9830);体重与全长之间为幂函数相关:y=5×10-6x2.786(R=0.9957);口径与日龄的关系为直线函数关系:y=0.1034x-0.0044(R=0.9939)。鱼苗早期阶段的生长速度存在显著性差异。军曹鱼早期鱼苗在3~6日龄时主要摄食原生动物、单轮幼虫和轮虫;7~12日龄时主要摄食桡足类无节幼体;13日龄以后主要摄食桡足类成体。仔、稚鱼阶段,军曹鱼的摄食活动呈现明显的昼夜节律,其饱满度指数均在12时前后出现最高峰,日摄食率分别为57.36%和14.78%。 相似文献
105.
Argo floats revealing bimodality of large-scale mid-depth circulation in the North Atlantic 总被引:1,自引:1,他引:0
Analysis of Argo float trajectories at 1 000 m and temperature at 950 m in the North Atlantic between November 2003 and January 2005 demonstrates the existence of two different circulation modes with fast transition between them. Each mode has a pair of cyclonic - anticyclonic gyres. The difference is the location of the cyclonic gyre. The cyclonic gyre stretches from southeast to northwest in the first mode and from the southwest to the northeast in the second mode. The observed modes strongly affect the heat and salt transport in the North Atlantic. In particular, the second mode slows down the westward transport of the warm and saline water from the Mediterranean Sea. 相似文献
106.
107.
分析C 虚拟继承状态下的对象复制语义学.通过分析当前主流C 编译器对这个语义的支持情况,比较了它们之间实现上的差异;最后提出一种基于软件编码的实现方案,并比较了各种方案的性能优劣,以求更大限度的发挥C 的性能. 相似文献
108.
On tectonic movement in the South China Sea during the Cenozoic 总被引:1,自引:1,他引:0
The tectonic movement taking place at the end of Cretaceous and the beginning of Cenozoic had opened the Cenozoic phase of polycyclic tectonic movements, then the whole crust of the South China Sea had been mainly subjected to the regional stress field of tectonic tension, which was characterized by rifting depression. Seven times of regional tectonic movement and sedimentation had been assembled into a geological development history of polycyclic oscillation. Especially, the tectonic movements were strongly intensified at the end of Cretacious and the beginning of Paleagene, between Late Eocene and MidOligocene, during Mid and Late Miocene. These three times of tectonic movement had built the most important regional tectonic interfaces in the South China Sea. Crust movements of the South China Sea were the result and epitome of interaction of the Eurasia, Pacific and IndoAustralia plates, that is, they were introduced by polycyclic changes of directions, rates and strengths of lithospheric movements and asthenospheric flows across the Pacific and IndoAustralia plates. 相似文献
109.
针对多尺度带乘性噪声系统,在多尺度最优滤波融合的基础上,进行状态最优固定域平滑算法的研究.通过推广得到的平滑算法需要大量的局部传感器参数,而分布式多尺度滤波融合后不能保留这些信息.针对这一弊端对算法进行改进,推导出仅使用融合后的一步预测及滤波值的平滑算法.该算法在线性最小方差意义下是最优的.计算机仿真验证了算法的可行性. 相似文献
110.
Thermal fronts and cross-frontal heat flux in the southern Huanghai Sea and the East China Sea 总被引:1,自引:0,他引:1
Synoptic features in/around thermal fronts and cross-frontal heat fluxes in the southern Huanghai./Yellow Sea and East China Sea (HES) were examined using the data collected from four airborne expendable bathythermograph surveys with horizontal approxmately 35 km and vertical 1 m(from the surface to 400 m deep) spacings. Since the fronts are strongly affected by HES current system, the synoptic thermal features in/around them represent the interaction of currents with surrounding water masses. These features can not be obtained from climatological data. The identified thermal features are listed as follows : ( 1 ) multiple boundaries of cold water, asymmetric thermocline intrusion, locally-split front by homogeneous water of approxmately 18 ℃, and mergence of the front by the Taiwan Warm Current in/around summertime southern Cheju - Changjiang/Yangtze front and Tsushima front; (2) springtime frontal eddy-like feature around Tsushima front; (3) year-round cyclonic meandering and summertime temperature-inversion at the bottom of the surface mixed layer in Cheju - Tsushima front; and (4) multistructure of Kuroshio front. In the Kuroshio front the mean variance of vertical temperature gradient is an order of degree smaller than that in other HES fronts. The southern Cheju- Changjiang front and Cheju -Tsushima front are connected with each other in the summer with comparable cross-frontal temperature gradient. However, cross-frontal heat flux and lateral eddy diffusivity are stronger in the southern Cheju - Changjiang front. The cross-frontal heat exchange is the largest in the mixing zone between the modified Huanghai Sea bottom cold water and the Tsushima Warm Current, which is attributable to enhanced thermocline intrusions. 相似文献