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121.
求解Euler方程的隐式无网格算法 总被引:1,自引:1,他引:0
研究了求解Eluer方程的稳式无网格算法,用点云离散计算区域,代替通常的网格划分;在当地点云上,引入二次平方极小曲面逼近计算空间导数,用Roe的近似Riemann解确定通量;并用LU-SGS算法求解离散得到的Euler方程稳式时间后差联立方程组,数值模拟了二维翼型跨音速绕流,由于无网格算法区域离散只涉及点云,具有灵活性,适合处理复杂的气动外形。 相似文献
122.
Christian Werner Grigorii Kokhanenko Gennadii Matvienko Vitalii Shamanaev Yurii Grachjov Igor Znamenskii Ulrich G. Oppel 《Optical Review》1995,2(3):221-224
First, in this report an overview is given on the use of the Russian laser altimeter in space “LORA” as a lidar for cloud measurements. Secondly, the influence of multiple scattering is verified by analysis of the backscatter signals from clouds having the excellent range resolution of a rangefinder.Presented at the 7th International Workshop on Multiple Scattering Lidar/Light Experiments (MUSCLE7), July 21–23 1994, Chiba, Japan. 相似文献
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125.
K Srinivasa Rao P S Goyal B A Dasannacharya V K Kelkar C Manohar S xxxV G Menon 《Pramana》1991,37(4):311-319
Micellar solutions of non-ionic surfactant triton X-100 (8% by weight) show phase separation at cloud pointT cp ~ 335 K. This paper reports results of small angle neutron scattering (SANS) experiments from this solution as a function of temperature between 298 and 332 K. The range of wave-vector transferQ, covered in these experiments is from 0.02 to 0.15 Å?1. It is seen that as one approachesT cp, the neutron scattering cross section diverges in the region of lowQ (<0.06 Å?1) while it is independent of temperature in region of largeQ(>0.06 Å?1). We believe that the divergence of scattering at lowQ with an increase in temperature is because of changes in the structure factorS(Q) of the solution. The measured distributions have been analyzed using four different models for inter-micellar potential. The models used to calculate the structure factorS(Q) are (1) mean spherical approximation (MSA) with Yukawa tail for attractive potential, (2) MSA with an attractive square well potential, (3) random phase approximation (RPA) with an attractive square-well potential and (4) Sticky hard sphere model (attractive square-well potential with Percus-Yevick approximation). The strengths of the attractive potential required to fit the SANS data are (?6.6 to ? 14.4)/kt for model (1), (? 6.6 to ? 15.0)/kt for model (2), (? 3.8 to ? 7.3)/k B T for model (3) and (?2 to ?2.7)/kt for model (4). On the basis of reasonableness of the derived strength of the potential near the phase separation temperature and its relative temperature dependence, it is concluded that present data favour the Sticky hard sphere model. 相似文献
126.
The nonionic surfactants Triton X 100 and Triton X 114 form isotropic micellar solutions around 25°C. One of the characteristic features of these solutions is the fact that at higher temperatures they undergo clouding and liquid-liquid phase separation. Addition of various additives to the surfactant solutions does change the temperature at which the clouding phenomenon occurs. In this paper such effect of additives on the clouding phenomenon of Triton X 100 and Triton X 114 are discussed. 相似文献
127.
研究了电子云扩大效应对Tb3+离子5d能级的影响. 利用光谱理论, 将电子云扩大效应比率β同Tb3+离子4f75d组态的自旋允许和禁阻跃迁能级的能级差联系起来, 通过复杂晶体化学键理论确定了化学键的共价性、 相应键体积极化率以及配体离子的有效电荷与β的线性关系, 同时得到了对β有影响并与Tb3+离子自身相关的因子. 相似文献
128.
针对传统的大数据信息监控云平台模式单一、虚拟化程度不高,容易导致信息泄露的问题,为了提高对大数据的信息安全溯源能力,提出基于Hadoop的大数据信息安全监控云平台设计方法。在信息资源云体系下构建大数据信息安全融合模型,通过信息挖掘与匹配方法把云平台中的数据资源、物理资源进行关联性整合,方便数据安全溯源,在Hadoop平台下构建多源信息资源云,建立用户接口注册机制,采用虚拟化技术进行信息保护,实现在云平台下进行信息安全溯源。实验结果表明,采用该方法进行大数据信息安全溯源,大数据信息分类存储性能较好,对异常数据挖掘精度较高。具有较好的信息安全保护能力,确保了信息安全。 相似文献
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130.
DONG Yu-Bing 《理论物理通讯》2006,45(5):885-888
In this work, a subtle role of the pion meson cloud effect on the
electric polarizabilities of the proton and neutron is stressed. It is
shown that the electric polarizabilities of the proton and neutron, and the
difference between the electric polarizabilities
of the proton and neutron can be explained by including the
pion meson cloud explicitly. However, the magnitude of the estimated
mean-square charge radius of the neutron is still far from the measurement. 相似文献