封闭特性

A new method based on the Fourier-Bessel series is proposed to calculate the higher-order harmonic components of a nonlinear ultrasound field in absorbing medium and an analytical solution of a series form is obtained. A closed analytical solution of the higher-order harmonics in the zeroth-order Bessel ultrasound field and the focused Gaussian ultrasound field is deduced to study the field property, especially the near-field property.

提出了一种基于Fourier-Bessel级数的新方法，用于计算吸收媒质中非线性超声场的高次谐波分量，得到其级数形式的解析解，由此推导出吸收媒质中零阶Bessel超声场、Gauss聚焦超声场高次谐波的封闭解析解，进而对其声场特性尤其是近场特性进行了研究。

The cylindrical shell of open circumambience with both ends simply supported and the cylindrical shell with clamped ends are analyzed, then the cylindrical shell of close circumambience with simple support and the other end clamped along straight edges are analyzed.

分析了两端简支的封闭圆柱壳、两端固定的封闭圆柱壳和两端简支直边固定的开敞圆柱壳的振动特性，同时研究了环向半波数对圆柱壳固有频率的影响，并给出了不同边界条件的振型图。

The characters of no-load member in closed complex structure and the reason of high-rigid of diagonal partition wall have been studied.

分析了组合封闭薄壁结构中无载构件的特性和对角筋板具有优良扭转刚度的原理，提出以结构的振型为依据，采用适当的筋板结构型式，可以提高结构的动刚度。

The paper also proved that motivation has two important properties:upper bound property and transaction-weighted downward closure property.

5论证了激励具有两个重要的数学性质：上界特性和事务权重激励向下封闭特性。

In HM-Two-Phase-Miner algorithm,transaction-weighted motivation downward closure property is adopted to cut down the search space.

HM-Two-Phase-Miner利用事务权重激励向下封闭特性进行减枝，有效提高了算法的性能。

HM-Miner uses the upper bound property to cut down search space,whereas HM-Two-Phase-Miner uses transaction-weighted downward closure property to achieve the same goal.

HM-Miner利用激励的上界特性剪枝，HM-Two-Phase-Miner则利用事务权重激励向下封闭特性剪枝。

The hydraulic loading system is developed and used to study the frost heaving characteristics of the subgrade soils under dynamic loading in closed system and open system . On the base of these work, the conclusions are as follows:1. Because of the the fine-grained fill, the frost deformations of Beijing-Baotou railway subgrade and Baotou-Lanzhou railway subgrade are holistically irregular, and great discrepancies exist among the frost heavings of subgrade at different sections.

本文根据冻害较严重的京包铁路、包兰铁路的气候、地质条件的调查和路基冻胀变形监测，结合路基土的性质对京包铁路、包兰铁路的冻害给出了评价；为了模拟振动荷载作用下土的冻胀，研制了液压动力加载系统；在室内采用实验方法对列车动荷载作用下包兰线路基粉质土在开敞、封闭系统下的冻胀特性进行模拟。

To find out behavioral characteristics of Tibet swine in Semitropics, 42 Tibet swine were introduced from Tibet to Guangzhou, and raised in close environment for a year in order to observe their routine behavior.

为了解西藏小型猪在亚热带地区的行为特性，对从西藏自治区偏僻山区引进到广州市的42头西藏小型猪，进行为期1年的封闭饲养，观察并记录其行为特性。

Furthermore,the stability behavior and accuracy characteristics of the algorithmare proven by a spectral decomposition method.

在前人工作的基础上，提出了一种新的用于解决结构动力分析问题的时间积分方法——Taylor级数方法；建立了求解线性问题和非线性项可以表示为多元多项式形式的非线性问题的Taylor级数方法的理论，并给出递归求解通式；阐述了该方法的程序实施过程，给出了计算流程图，并在非线性有限元分析平台NFAP中嵌入了Taylor级数方法的计算模块；利用谱分解的方法分析了该方法的稳定性和精度特性，以封闭的解析形式给出了描述积分法特性的周期延长率和振幅衰减率的表达式；通过对该方法的理论分析和特性研究，阐述了该方法的可行性和高效性。

In the paper, we investigate, respectively, the unsteady transport properties of heat and moisture in enclosure under constant wall heat flux and constant wall temperature when porous particles are small and Darcy number is lower, the effect of conductivity ratio, heating conditions and other parameters on the heat transfer rate of enclosure when particles are larger and Darcy number are higher.

并分别对多孔颗粒较小时的低Da数封闭腔内的非饱和渗流与传热，及颗粒较大的高Da数封闭腔内的非饱和自然对流行为进行了数值模拟，研究了低Da数时湿分与热量在恒热流与恒壁温条件下的非稳态传递特性，高Da数时封闭腔的传热与流动特性、达西效应以及导热比、加热条件等对空腔传热系数的影响。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。