Aim To separate texts from graphics on mechanical engineering drawings. Methods By improved labeling run, the size of circumscribed rectangle and pixel density about the connected graphs on a drawing were gained, according to these value, texts not sticking to graphics could be separated from a drawing. The concept of appendant block was introduced, using the appendant block, texts sticking to graphics could be determined and cut. Results Texts and symbols on mechanical engineering drawings can be separated well. Conclusion This method is simple and fast, it does not destroy the shape of texts and symbols, it can be used for separating texts and symbols from all linear graphics.
Cluster warhead dispersing technique is analyzed with gas dynamic theory. It is seen that the front cover opening and two stage dispersing system is suitable for guided sub missiles whose number is not so large. The interior ballistic performances of this system are calculated with numerical calculation method. The performances such as the pressure in the pressure chambers and the velocity of the sub missiles are obtained in curve form.
A method, by which the broken edge of mechanical engineering drawings being binarised can be eliminated and the whole edge of mechanical engineering drawing can be got, is given. To all points of a connected area on the image of the modular maximum value of wavelet transform at scale 2 2, the averaging grey value method is used to their grey values, then the edge of the dim place is continuous after the maximum variance threshold method is used. All these methods are fast, they can be used for all linear graphics having nothing to do with the grey value, its application scope is wide.
战术导弹同心筒发射装置(concentric can ister launcher,CCL)是舰载导弹新一代垂直发射装置.其内外筒间隙、导弹发动机喷口与筒底的距离、导流锥的高度与型面半径、底板的形状与尺寸等参数都会对筒内流场产生影响.针对内外筒间隙这一影响流场的关键结构参数,利用先进的大型流体力学软件F luent对不同间隙时的筒内超声速流场进行了三维数值模拟,并对流场的流动机理及参数分布进行了分析,给出了研究结论,为工程设计提供了理论依据.
