数字化设计在水泥工程结构设计中的应用

水泥工程设计已经进入数字化设计时代。以某国外项目水泥磨装配式排架结构设计为例,利用BIM技术,将设计师从繁重的重复性、低价值的工作中解放出来,将更多的精力用在多专业协同、专业技术创新上。数字化设计基于现实建造条件和场景,通过专业协同、多软件协同进行计算机模拟及虚拟建造,最后交付"零差错"的专业的数字化设计产品,及时高效地为项目建设提供数字化信息,为项目的数字化、智能化建造提供支撑。

SPEED UP RATIONAL POINT SCALAR MULTIPLICATIONS ON ELLIPTIC CURVES BY FROBENIUS EQUATIONS

Let q be a power of a prime and φ be the Frobenius endomorphism on E(Fqλ), then q = tφ- O2. Applying this equation, a new algorithm to compute rational point scalar multiplications on elliptic curves by finding a suitable small positive integer s such that qs can be represented as some very sparse φ-polynomial is proposed. If a Normal Basis (NB) or Optimal Normal Basis (ONB) is applied and the precomputations are considered free, our algorithm will cost, on average, about 55% to 80% less than binary method, and about 42% to 74% less than q-ary method. For some elliptic curves, our algorithm is also faster than Muller's algorithm. In addition, an effective algorithm is provided for finding such integer s.

大型平面天线可展开支撑结构变形影响因素分析

可展开支撑结构是大型车载天线的重要组成部分,其变形直接影响天线的性能指标。为控制天线可展开支撑结构工作状态下的变形,针对某大型平面天线复合材料可展开支撑结构,采用有限元法建立仿真分析模型,在结构形式不变的情况下,分析不同复合材料铺层方案及背部支撑位置对典型工况下结构变形的影响。分析结果表明,增加复合材料铺层厚度,可以减小变形。对于给定结构形式可展开支撑结构,驱动臂支撑点选取在系统整体重心所在纵向线上可使得整体结构变形最小。分析结果为大型天线可展开支撑结构优化设计提供了参考。