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Advanced numerical simulations were introduced in soil water research,such as finite analysis method,characteristic finite element method,and alternating direction finite element method.

土壤水研究的数值模拟方法也有一些突破，如有限解析法、特征有限元法、交替方向有限元法等。

Shadow effect can not be neglected for thermal analysis of spacecraft,Accroding to the angle between solar light and antenna orbit plane and its orbit location,analytical geometry method was used for accurately calculating solar radiation heat flux distribution of reflector surfaces.To analyze the temperature field under heat flux,the formulations of net radiation flux density between two gray elements and the net flux density of gray surface under external thermal flux were deduced.Based on the characteristic of space environment,the nonlinear temperature distribution in transverse direction of reflector shell self radiation were considered,the finite element formulations were given for orthogonal material layered shell by Galerkin method.A layered element including a inner heat source layer was proposed,and the finite element formulation expressed by DOF of the inner heat source layer were put forward with temperature and heat flux boundarys between adjacent layer.

单馈反射面赋形天线是未来星载天线发展的一个重要形式，分析了基于物理光学、几何光学和几何绕射理论的理想反射面辐射场；介绍了基于几何光学的反射面天线赋形方法；针对赋形过程中辐射场的快速分析要求，比较分析了基于物理光学的Fourier-Bessel和Jacobi-Bessel级数展开方法以及GB展开分析方法；利用GB展开快速分析方法在20GHz频率下对0.6m口径的天线进行赋形分析，实现中国大陆的30dB增益覆盖，通过数值计算研究了固定增益期望下的口径尺寸随频率的变化，以及频率为20GHz的不同尺寸天线赋形后的覆盖目标区域最大增益的变化情况。

The relationship between acoustic wave direction,laser incident angle,and laser diffraction angle of TeO2 acousto-optical deflector with acoustic frequency was analyzed based on the TeO2 crystal acousto-optical characteristic and Dixon equations under abnormal Bragg diffraction.

根据晶体的声光特性以及反常布喇格衍射的Dixon方程，得出了氧化碲声光偏转器在反常布拉格衍射条件下的参量矢量关系。分析了超声波方向、入射光角度、衍射光角度与声波频率之间的关系。

In this thesis, we take the delay r as a bifurcation parameter to investigate the Hopf bifurcation phenomenon in system (1). By analyzing the associated characteristic transcendental equation of system (2), and using the Hopf bifurcation theorem, we obtain one condition for the existence of Hopf bifurcation in system (1). Furthermore, based on the center manifold theorem and the method of normal form, some interesting results about the properties of Hopf bifurcation are obtained, including the direction of Hopf bifurcation and stability of Hopf bifurcating periodic solutions.

我们以时滞T作为分支参数，研究了系统(1)的Hopf分支现象：通过分析系统(2)的特征超越方程，结合利用Hopf分支定理获得了系统(1)的Hopf分支存在的一个条件；利用中心流形定理和正规形方法分析了系统(1)的Hopf分支的性质，包括分支的方向和分支周期解的稳定性。

Based on image statistical characteristic, the algorithm can search automatically the boundary start-point using Sobel operator and special template operation, then according to the connection status of every boundary point in its 8-connection neighbor field, seek automatically the search direction, form the whole data collection of a target boundary outline.

该算法依据目标图象特征，在二值图象中利用Sobel算子和特定的模板操作，自适应搜索边界起点；然后，按照每个边界点在其8邻域内的连通情况，自动寻找搜索方向，形成了完整目标边界轮廓数据集。

According to the principle of A-O interaction and quartz′s different characteristic in the direction of parallel and perpendicular acoustics field, with a quarter-wave plate being inserted in an AO Q-switch Nd∶YAG laser cavity between mirror and Q-switch, AO Q-switch′s Bragg diffraction efficiency formula is put out theoretically. Consequently, the conclusion has been drawn by calculating simulation that the ability of a single AO Q-switch′s switching CW Nd∶YAG laser is increased.

结合声光相互作用理论和声光介质熔石英在平行和垂直于声场的两个方向具有不同声光优值的特性，理论推导了腔内引入四分之一波片后声光Q开关的布喇格衍射效率公式，计算模拟得出引入四分之一波片能够有效地提高声光Q开关关断连续Nd∶YAG激光的能力。

According to the principle of A-O interaction and quartz＇s different characteristic in the direction of parallel and perpendicular acoustics field, with a quarter-wave plate being inserted in an AO Q-switch Nd : YAG laser cavity between mirror and Q-switch, AO Q-switch＇s Bragg diffraction efficiency formula is put out theoretically.

结合声光相互作用理论和声光介质熔石英在平行和垂直于声场的两个方向具有不同声光优值的特性，理论推导了腔内引入四分之一波片后声光Q开关的布喇格衍射效率公式，计算模拟得出引入四分之一波片能够有效地提高声光Q开关关断连续Nd：YAG激光的能力。

The second is that the characteristic of time and direction of ME is poor.

二是德育教学的时代性、针对性不强。

In the end this paper concludes the technical characteristic and development direction of the latest environmental impact assessment modeling software.

无论哪一种软件系统，都需要对环境现状质量做出确切的评价，从而准确地对未来环境污染进行预报。

Ni6 cluster is an octahedron belonging to Oh point group. Its 3Eg orbital presents strong negative exchange coupling and has a trend of antiferromagnetic couplings. Ni5 cluster is of three-side pyramidal structure belonging to point group C3v. The magnetic moment direction of Ni atom lying on vertex of the pyramid is antiparallel to the moment direction of the Ni atoms lying on underside of the pyramid, which present the characteristic of ferrimagnetic couplings.

具有Oh点群对称的八面体原子簇Ni6的3Eg轨道上存在很强的负交换耦合，呈现反铁磁耦合趋势；具有C3v点群对称的三边金字塔结构的原子簇Ni5位于塔顶点的Ni原子与基面上的Ni原子磁矩方向相反，但大小不等，呈现出亚铁磁交换耦合特征。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。