方向

This paper studies the global topological structure of a kind of plane homogeneous fifth system with three special direction Suppose the system has are only one finite singular point (0,0), then we can assume b50=0, which special directions are determined by equation G=0, introduce Poincare transformation to discuss infinite singular points, according to the coefficient conditions, list all possible infinite singular points and special directions, judging their type, drawing out all kinds of phase portraits when it has three special direction.

研究了一类平面齐五次系统当其只有唯一的有限远奇点且具有三对特殊方向时的全局拓扑结构及系数条件。假设系统只有唯一的有限远奇点(0，0)，不妨设b50=0其特殊方向由示性方程G=0给出，引进poincare变换研究无穷远奇点，再根据定理中的系数条碎，列出系统所有可能的无穷远奇点和特殊方向，并判断其类型，由此画出系统具有三对特殊方向时的全局相图。

Any high Re number flow over bodies consists of three basic flows: the flow with convection-dominant in all spatial directions, the flow with convection-diffusion competition in all directions and the flow with convection-dominant in part directions and convection-diffusion competition in part directions, which is called the interacting shear flow; the features of the three basic flows are different; their simplest conservation equations, i.e. the Euler equations, Navier-Stokes equations and diffusion parabolized NS equations, have different mathematical characteristics; there is a great disparity in domains of the three basic flows and the domains of NS equations are very small. Therefore, adopting Euler-DPNS-NS equation system to analyze and compute high Re number flows over bodies is a logical approach. There exists a mutual examined-complemented relationship of this approach with the usual one of adopting only NS equations.

主要内容如下：（1）高Re数绕流包含3种基本流动：所有方向对流占优流动、所有方向对流扩散竞争流动和部分方向对流占优部分方向对流扩散竞争流动，3个基本流动的特征彼此不同且在流场中所占领域大小彼此相差悬殊，NS方程区域很小，它们的最简单控制方程组Euler、Navier-Stokes和扩散抛物化NS方程组的数学性质彼此不同，因此利用Euler-DPNS-NS方程组体系分析计算高Re数绕流流动就是一个合乎逻辑的选择，该法与利用单一NS方程组的常用方法可以彼此检验和补充。

Constitution:the button-sewing machine comprises:a fixing means 构件 for fixing a buttonand an article being sewn;a moving means for moving the fixing means to stitch the button to the article being sewn with seams of a specified sewing pattern; a fixed blade; a moving blade for drawing a thread and then moving to cut the thread by the cooperation with the fixed blade;and a button,wherein the machine has a control means for controlling a fabric transferring means to move the button to a preset position before cutting the thread.

一种钉扣机，设置有布料保持件的可动、固定切换机构，该切换机构在钉扣缝制时可在以下两种状态之间进行切换：将布料保持件固定保持在规定位置上从而停止该布料保持件在左右方向上的移动的状态、或者解除对布料保持件的位置固定从而使该布料保持件通过可动台与纽扣保持件一起在前后方向、左右方向上移动的状态，在该切换机构上安装有可在左右方向上的一定范围内调整布料保持件的固定保持位置的位置调整机构，由此可使整体结构简单，可实现小型化、轻量化及低成本化，且即使在将柔软的布料作为缝制对象时也不会出现缝制褶皱等，另外，无论线的种类和粗细如何，都可进行缝制品质高的钉扣。

The results show that the vibration intensity of the substructure has a connection with the depth of the well, the geological condition and the density of drilling fluid; the horizontal vibration of the substructure is mainly caused by bent kelly; the included angle between the axis of cardan shaft and the derrick floor is also the cause of the vibration in three directions, and the cause of t...

分析结果表明，底座的振动强度与井深、地质条件和钻井液密度有关；弯曲的方钻杆是造成底座水平方向振动的最主要原因；万向轴因与钻台面存在夹角，从而引起底座在三个方向的振动；采用四挡钻进时，万向轴的工频及其倍频接近底座垂直方向的固有频率是引起底座在该方向振动强烈的原因。

The wave velocity ratio vertical to the stratum of the rock samples is usually less than that in parallel direction, and the relative increment of wave velocity ratio between the vertical direction and the parallel direction decreases as the wave velocity ratio in vertical direction gradually increases.

波速比的各向异性特征主要表现为垂直层理方向上的波速比普遍小于平行层理方向，且两方向波速比的相对增量还随着垂直层理方向上的波速比的增大而逐步减小。

The proposed robust road main direction detection method consists of initial main direction extraction based on the direction histogram of structure tensor and precise direction detection on vectorized edge image. Experiment results demonstrate its robustness and precise. The proposed Gibbs-sampling-based method models road network with marked point process and can effectively extract road network with initial configuration. However it is slow and still can not deal with single and isolated road segment. These problems can be solved by the real-time method. And experiments verify that the real-time method is fast during extracting road segment.

提出的稳健道路局部主方向提取算法以结构张量为基础，通过方向直方图确定大致主方向，并通过矢量化边缘进一步计算准确的方向角，实验结果表明具有良好的稳健性和准确性；提出的基于Gibbs采样的交互式道路网提取方法采用标记点过程对道路网进行建模，在给出初始构造项的情况下，能有效的提取出指定道路网；提出的实时交互式道路段提取算法弥补了上一方法无法处理单一直线道路段和计算过程慢的不足，是上一方法的有益补充，实验结果表明算法能快速提取道路段。

Results The length change of the long axis was smaller than the absolute value of the length change of the short axis in the coup site air bubble; the length change of the long axis was bigger than the absolute value of the length change of the short axis in the contrecoup site air bubble.

结果 撞击点处的气泡在短轴方向上的轴长变化大于长轴方向上的轴长变化，对冲点处的气泡在短轴方向上的轴长变化小于长轴方向上的轴长变化。

The pick-up gear is rotated when the motor is rotated in a first direction, the feed gear is rotated when the motor is rotated in a second direction, and the discharge gear is rotated constantly in one direction regardless of the rotation direction of the motor.

当电动机沿第一方向旋转时，拾取齿轮被转动，当电动机沿第二方向旋转时，送纸齿轮被转动，以及无论所述电动机的旋转方向为何，排纸齿轮恒定地沿一个方向旋转。

Evidence suggests that 1 under more stable stratification, the basic flow, if moving faster at low and high levels (particularly in the presence of jets there), allows a resulting meso-β unsteady wave to propagate eastward with respect to basic flow and even at greater velocity compared with it; 2 vertical windspeed shear of basic flow causes instabilities of the TWT perturbation; 3 considering the second derivative of basic-flow wind with respect to z (denoted by zz≠ 0 which is simply given as β* hereafter) the expression for the phase velocity of vortex Rossby wave is obtained, which is unidirectional in propagation with respect to basic flow; 4 VRoW has its physical origin from β*, i.e., from z-varying heterogeneities of y-direction averaged vorticity of the basic flow field; 5 VRoW phase velocity is associated with zonal wave number k, its energy is dispersive and the group velocity exists in the x direction; 6 when windspeed meets the condition of β*, TWT disturbance instability may be that of mixed VRoW and gravity wave; 7 if basic flow is subject to linear shear but does not meet the condition of β*, the TWT instability is that of inertia-gravity wave.

在大气层结比较稳定的情况下，如果基本气流在低层和高层较大(有可能存在低空急流和高空急流)，此时产生的β中尺度不稳定扰动相对于基流向东传播，甚至于快速向东传播。基本气流在垂直方向上的风速切变对于中尺度横波型的扰动起着不稳定的作用。如果考虑基流的二次切变，可以得到涡旋Rossby波的相速度表达式，涡旋Rossby波相对于基本气流是单向传播的。涡旋Rossby波产生的物理根源是基本流场的风速二次切变，亦即基本流场y方向的平均涡度在空间z方向上的不均匀所致。涡旋Rossby波的相速度与纬向波数也有关，它的能量是频散的，其在纬向x方向也存在群速度。在基本流场的风速存在二次切变时，横波型不稳定可能是混合的涡旋Rossby重力波的不稳定；而在基本流场的风速仅仅存在线性切变，不存在二次切变时，横波型扰动的不稳定则是重力惯性波的不稳定。

The simulation is based on four methods, including the discrete ordinates method with donor-cell interpolation, the DOM with van Leer interpolation, the modified DOM with donor-cell interpolation and the modified DOM with van Leer interpolation. The computational results are compared with those obtained by the Monte Carlo method.

本模拟采用四种方法，包括以donor-cell内差的离散方向法，以van Leer内差的离散方向法，以donor-cell内差的修正的离散方向法，以van Leer内差的修正的离散方向法，其计算结果将与蒙地卡罗法所得到的结果作比较。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。