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一走进大余县第二冶金化工厂,最惹人注目、最令人感兴趣的是那一只金杯,一只特大的金杯,用钢筋水泥塑的,圆盘托起,外表金黄金黄的在闪亮。厂长严国栋告诉我:“金杯,象征我们的心愿,象征我们的事业和成功。”这话不假,这个厂从1985年上半年筹建至1988年,仅三年多时间就取得了赣州地区乡镇企业的四个第一:年产值第一个超千万元;第一个获得江西省进出口商品检验局的 相似文献
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This paper presents an analytical solution for the problem of the long wave reflection by a series of artificial bars with parabolic configuration in terms of the associated Legendre functions. It is shown that both the reflection and transmission coefficients depend solely upon the number of bars, the dimensionless bar height, the dimensionless bar width and the dimensionless bar distance. Particularly, under the Bragg resonance condition, i.e., the distance between two adjacent bars is about half of the wavelength of the normal incident waves, the analytical solution for the peak Bragg resonant reflection is obtained, which reveals that the peak Bragg resonance depends upon the number of bars, the dimensionless bar height and the dimensionless bar width. Based on this solution, the optimization of the parabolic bars is made to obtain the maximum Bragg resonance and a group of optimal curves, which may be very useful in the design of Bragg breakwaters with parabolic bars. 相似文献
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本文介绍了冶金工业部地质勘查总局建立的经济效益考核指标体系的指导思想、原则、指标设置和考核评价方法。 相似文献
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