有计算机去检查NC指令中的错误

针对ＮＣ指令中最常出现的错误,提出了用计算机去检查的思想,并详述了检查的基本原理和相应的实现方法。     

MAGNETIC MOMENT,CURIE TEMPERATURE AND SPIN WAVE EXCITATION FOR AMORPHOUS Fe_(90-x)Si_xZr_(10) ALLOYS

The magnetization curves at 1.5 K and thermomagnetic curves for amorphous Fe_(90-x)Si_xZr_(10)(x=0,4,7 and 10)alloys prepared by the drum spinning technique have been measured with an extracting sample magnetometer.It is obtained that the average magnetic moment,,per magnetic atom and Curie temperature,T_c,in the amorphous FeSiZr alloys increase with increasing Si content.The and T_c are found to be quite small,compared with amorphous FeSiB alloys.This unusual behavior is suggested to be due to the presence of the Fe—Fe antiferromagnetic interactions.The temperature dependence of magnetization at lower temperature is in accordance with Bloch's T~(3/2) law.Calculation shows that the spin wave stiffness constant,D,increases with increasing Si content from 0.37 meV·nm~2 for x=0 to 0.538 meV·nm~2 for x=10.The values ofindicate that the range of the exchange interaction is roughly the mean atomic distance of nearest neighbours.     

关节型工业机器人扭转振动的伺服补偿技术研究

针对工业机器人用RV减速机传动误差所引起的动态失稳现象,在建立由驱动电机-RV减速机-负载所构成的机电耦合系统的基础上,同时考虑负载侧不宜安装传感器的限制条件,依据转矩波动引起转速波动的原理,将由状态观测器间接得到的能够反映转矩波动变化的状态变量——负载加速度变化率作为反馈控制量,对电磁转矩进行实时补偿。经系统的时频域性能分析证明,补偿后的电机转矩命令值抵消了转矩波动的影响,负载侧转速波动得到了很好的抑制,能够极大提高工业机器人在变工况下的动态工作精度。     

数字录放音系统的总谐波失真与动态范围及测量

数字录放音系统的动态范围和总谐波失真与模拟量放音系统相比是差别的，本文讨论了数字录放音系统的动态范围和总谐波失真的意义及其测量原理。     

非晶态Fe_(90-x)Si_xZr_(10)合金的磁矩,Curie温度和自旋波激发

非晶态Fe_(90-x)Si_xZr_(10)(x=0,4,7,10)合金是用单辊急冷方法制备的,用提拉样品磁强计测量了样品的磁化曲线和热磁曲线。发现每个磁性原子的平均磁矩μ和Curie温度T_c随Si含量的增加而增加,与相应的非晶态FeSiB合金相比,非晶态FeSiZr合金的μ和T_c明显偏低,认为这一反常现象是Fe-Fe原子间的反铁磁耦合的存在所致。低温下样品的磁化强度与温度的关系较好地符合Bloch T~(3/2)定律,得到自旋波劲度系数D从x=0时的0.37meV·um~2增加到x=10时的0.538meV·um~2,计算出交换相互作用范围都是在最近邻原子间的距离。     

MA Fe-(Nb,Ti)-B纳米晶粉末热压烧结及磁性能

研究了MA法和热压烧结工艺制备的Fe84Nb7B9和Fe80Ti8B12合金粉末的产物及其块体合金的微观组织结构和磁性能。结果表明：(1)20hMA后，Fe84Nb7B9和Fe80Ti8B12均形成了单相bcc米晶过饱和固溶体，相对前者，后者纳米晶组织热稳定性明显提高，过饱和固溶体相分解温度略有降低；(2)在30MPa／900℃／0．5h热压条件下，Fe84Nb7B9和Fe80T8B12块体合金相对密度分别为96．7％和95．5％，相对前者(多相组织)，后者由超细晶(50～200mm单相α-e组成；(3)Fe80TiB12块体合金软磁性能(σ8=198．6emu／g，Hc=54．6Oe)明显高于Fe84Nb7B9块体合金(σ8=162．9emu／g，Hc=105．1Oe)，此与纳米晶粉末在热压烧结过程中所形成相的种类和晶粒尺寸大小有关。     

快淬（Fe1—xGax）77.5Nd4B18.5合金的磁性及其晶化行为

研究了快淬(Fe_(1-x)Ga_x)_(77.5)Nd_4 B_(18.5)合金的磁性,晶化行为,以及Ga含量和热处理对其硬磁性和相组成的影响,结果表明随着Ga含量x的增加,非晶态样品的Curie温度提高,而晶化温度降低,Fe原子的平均磁矩近似为一个常数,用X射线衍射和热磁测量分析了热处理后样品的结晶相,还研究了室温矫顽力与Ga含量的关系。     

Er对Mo5Si3基合金组织与性能的影响

通过X射线衍射(XRD)、金相显微镜、扫描电镜(SEM)、能谱分析(EDS)及压痕技术研究了Er对Mo5Si3基合金(钼硅质量比5：1)室温组织与性能的影响。研究结果表明：Er的添加导致了三元化合物相Mo3Er2Si4的形成：合金的组织形貌随Er含量不同有所差异，且随Er含量增加，组织中MoSi2相逐渐减少，三元化合物的含量则逐渐增加：过渡族元素Er在MoSi2中不固溶，在Mo5Si3中的溶解度也极小：Er含量为1wt％时得到略高的室温硬度值。Er难以明显改善室温断裂韧性。     

基于信任度的并行化社区发现算法

现有的社交网络快速划分社区算法存在质量低、不能充分利用节点链接信息的问题,而效果较好的划分算法也存在时间复杂度高、无法应用于大规模社交网络的问题。为此,提出一种基于MapReduce的社区发现算法。利用PGP算法内信任者推荐模型迭代计算用户之间的信任强度,通过社区传播的方式聚合节点。在经典数据集上和大规模新浪微博数据集上进行实验,结果表明,该算法能有效度量用户间的信任度,得到准确的社区发现结果。     

A parallel portfolio approach to configuration optimization for large software product lines

Software product line (SPL) engineering demands for optimal or near‐optimal products that balance multiple often competing and conflicting objectives. A major challenge for large SPLs is to efficiently explore a huge space of various products and satisfy a large number of predefined constraints simultaneously. To improve the optimality and convergence speed, we propose a parallel portfolio approach, called IBEAPORT, which designs three algorithm variants by incorporating constraint solving into the indicator‐based evolutionary algorithm in different ways and performs these variants by utilizing parallelization techniques. Our approach utilizes the exploration capabilities of different algorithms and improves optimality as far as possible within a limited time budget. We evaluate our approach on five large‐scale real‐world SPLs. Empirical results demonstrate that our approach significantly outperforms the state of the art for all five SPLs on a quality indicator and a diversity indicator. Moreover, IBEAPORT quickly converges to a relatively stable hypervolume value even for the largest SPL with 6888 features.