基于S变换和共空间模式的运动想象脑电特征提取

针对共空间模式算法运用于运动想象脑电信号特征提取分类正确率低、计算实时性差等问题,提出运用S变换结合共空间模式算法对脑电信号进行特征提取方法。经过S变换后的信号具有更加明显的时、频、相特征,再运用共空间模式算法提取特定任务信号成分的特征,最后用支持向量机进行分类。实验结果表明:在S变换采样数较多的情况下,平均正确率达到92.8%,大大超过单纯使用共空间模式算法的正确率。如果降低S变换的采样率,系统实时性得到大幅提升,平均运行时间仅为0.85 s,平均分类正确率可达89.8%,比仅运用共空间模式算法的运行时间缩短30.9%。可见,不仅可提高运动想象脑电信号的分类正确率,还可以提高分类的实时性。     

Gleason问题在多复变F(p,q,s)空间上的可解性

在0p∞,0≤s∞,max{-n-1,-s-1}q∞的条件下,证明了Gleason问题在C~n中以单位球为支撑集的一般函数空间F(p,q,s)上是可解的.     

单位球上F(p,q,s)到μ-Bloch空间的点乘子

设μ是正规函数,文中探讨了多复变中单位球上一般函数空间F(p,q,s)到广义Bloch型空间β_μ的点乘子,并给出了几个推论.     

新型复合干燥剂吸附分形特性

基于复合干燥剂表面的氮气平衡吸附实验数据,利用分形等温吸附理论模型,对氮气平衡吸附量进行非线性拟 合,确定了表面分形维数,并对表面几何形态进行定最描述,得到了分形等温吸附式;对比测试和拟合结果,发现分形维 数随氯化钙含量增加几呈波动变化,分析得到的单分子层饱和吸附量与实验数据基本一致。     

THE THREE-DIMENSIONAL STRUCTURE OF TRICHOSANTHIN MOLECULE

A model completed recently of two trichosanthin molecules in an asymmetric unit belonging to themonoclinic system is reported. It can be seen that the molecular, structure consists of two domains, onelarge and one small, and that there are some features in the secondary structure. The dissimilarity be-tween two molecules as well as their interactions in an independent unit rorrelated in a non-symmetricway has been described. moreover, the binding sites of the heavyatom position in the derivatives are alsodiscussed.     

扫描电路的相对时差

研究了简单式、自举式、密勒式和恒流管充电式四种扫描电路的相对时差与其电源利用系数、非线性系数的关系，并且阐明了扫描电路相对时差的实用价值。     

工程测量在工程建设中的重要性

测量学是从人类生产实践中发展起来的一门历史悠久的科学，是人类与大自然作斗争的一种手段，古有“陆行乘车，水行乘船，泥行乘橇，山行乘轿，左准绳，有规矩，载四时，以开九州。通九道，陂九泽，度九山”的记载，实际都是工程测量的作用，将详细阐述工程测量学在工程建设施工中及运营阶段中的重要性。     

增量调制系统的间隙零码及其抑制方法

DM制CDA的间隙零码的有害影响是电源的功耗很大，从而降低了增量调制丁类放大器总的工作效率；为了消除间隙零码的有害影响，设计了一种间隙零码的抑制电路，采用由音频信号形成的开关信号去封闭编码器的三变量与门的办法既可以消除间隙零码的不良影响，还可以消除间隙噪声干扰，从而大大提高了CDA电路的性能．     

Measurement of large aspheric surfaces by annular subaperture stitching interferometry

A new method for testing aspheric surfaces by annular subaperture stitching interferometry is introduced. It can test large-aperture and large-relative-aperture aspheric surfaces at high resolution,low cost,and high efficiency without auxiliary null optics.The basic principle of the method is described,the synthetical optimization stitching model and effective algorithm are established based on simultaneous least-square fitting.A hyperboloid with an aperture of 350 mm is tested by this method.The obtained peak-to-valley (PV) and root-mean-square (RMS) values of the surface error after stitching are 0.433λand 0.052λ(λis 632.8 nm),respectively.The reconstructed surface map is coincide with the entire surface map from null test,and the difference of PV and RMS errors between them are 0.031λand 0.005λ,respectively. This stitching model provides another quantitive method for testing large aspheric surfaces besides null compensation.