分段滤波用于消除脉搏血氧检测中多种运动干扰的研究

脉搏血氧饱和度检测仪可以无损、实时地检测动脉血液中的含氧百分比,从而快速对人体的呼吸状况以及心肺功能作出判断,但其检测精度极易受到测试部位运动的影响.人体测试部位的运动大致可以分为突发性运动干扰以及周期性的运动干扰.突发性干扰表现在局部脉搏波的波形突变上,而周期性的干扰体现在多个局部脉搏波的波形的周期性变化上.文章有针对性地提出了一种将微分阈值分段与迭带中值滤波相结合的方法来剔除突发扰动的方法,并且在上诉方法上再加上一级多点移动平滑以消除周期性运动干扰.实验证明该方法在消除多种运动伪差上有着较好的效果,且该方法计算简单,易于实现,有着一定的实际应用价值.     

Beam dynamics and RF design of trapezoidal IH-RFQ with low energy spread

Beam dynamics and RF design have been performed of a new type trapezoidal IH-RFQ operating at 104 MHz for acceleration of 14C+ in the framework of RFQ based 14C AMS facility at Peking University. Low energy spread RFQ beam dynamics design was approached by the method of internal discrete bunching. 14C+ will be accelerated from 40 keV to 500 keV with the length of about 1.1 m. The designed transmission efficiency is better than 95% and the energy spread is as low as 0.6%. Combining the beam dynamics design, a trapezoidal IH-RFQ structure was proposed, which can be cooled more easily and has better mechanical performance than traditional RFQ. Electromagnetic field distribution was simulated by using CST Microwave Studio (MWS). The specific shunt impedance and the quality factor were optimized primarily.     

Asymmetric Heat Conduction in One-Dimensional Hard-Point Model with Mass Gradient

The heat conduction in a one-dimensional （1D） hard-point model with mass gradient is studied. Using numerical simulation, we find an asymmetric heat conduction in this model with greater heat current in the direction of mass increase. The increase of temperature gradient, mass gradient and system size axe found to enhance the asymmetric heat conduction. Based on the collision dynamic of a haxd-point particle, we give a qualitative explanation for the underlying mechanism of asymmetric effect.     

父代种群参与竞争遗传算法几乎必然收敛

熟知,标准遗传算法如不采用“杰出者记录策略”则必不收敛。本文发现：允许父代种群参与竞争是标准遗传算法几乎必然收敛的条件。特别地,我们运用鞅收敛定理证明：允许父代种群参与竞争型遗传算法能以概率1确保在限步内达到全局最优解,且收敛与种群规模无关。所获结果对该类遗传算法的应用奠定了可靠基础。     

基于SOS的脉冲功率源技术新进展

 研制了基于SOS的胡杨200和胡杨700脉冲功率源。给出了胡杨200和胡杨700的电路原理、组成结构和实验波形。介绍了在SOS脉冲功率源上开展的高重复频率强流电子束产生、长寿命阴极实验、绝缘介质的高重复频率击穿实验和低引导磁场无箔二极管等实验研究进展。经测试，胡杨200在2 kHz重复频率、负载阻抗200 Ω下，输出电压200 kV，脉冲宽度约35 ns，平均输出功率大于10 kW；在300 Hz条件下可连续运行。胡杨700同样为全固态脉冲功率源，其设计指标:输出电压700 kV，电流5 kA，脉冲宽度约40 ns；经初步调试在150 Ω电阻负载上单脉冲输出指标达到660 kV，4.4 kA，脉宽约70 ns。     

水解聚丙烯酰胺分子量的表征

在 2 5℃、0 .5mol/LNaCl水溶液中 ,测定了 40种水解聚丙烯酰胺样品的特性粘数 ,求出了Mark -Houwink方程常数K、α值。在水解度 2～ 40 %之间 ,发现K、α对水解度具有强烈的依赖性 ,并且特征粘数与水解度的平方根成直线关系。利用本文所求的 K、α值预测本研究的水解聚丙烯酰胺样品分子量 ,其误差在± 8%之间 ;而对文献数据进行处理 ,其平均误差为 11.12 %。     

Single and Multi-Interval Legendre τ-Methods in Time for Parabolic Equations

In this paper, we take the parabolic equation with periodic boundary conditions as a model to present a spectral method with the Fourier approximation in spatial and single/multi-interval Legendre Petrov–Galerkin method in time. For the single interval spectral method in time, we obtain the optimal error estimate in L ²-norm. For the multi-interval spectral method in time, the L ²-optimal error estimate is valid in spatial. Numerical results show the efficiency of the methods.     

污染气体红外光谱鉴别器的优化设计

针对污染气体红外光谱特征分布的复杂性，结合几种线性分类器的特点，通过对每个环节的深入分析，设计出一种混合多叉树状光谱鉴别器。实验结果表明：此光谱鉴别器不仅结构简洁，设计合理，具有很高的分类能力和判别准确率，而且具有较好的灵活性和稳定性，完全满足快速识别的需要，是一种高效的光谱鉴别器。     

X-ray Crystal Structure of a Mononuclear Copper (Ⅱ) Complex with Unusual Monodentate O-coordination of Carboxylate Group of Isonicotinate

Copperproteinsitesareassociatedwithavarietyofvitalbiologicalfunctions,includingelectrontransfer,anddioxygentransportandactivationl.ThelargemolecularweightandcomPlexnatureoftheproteinsmakedetailedstudiesoftheiractivesitesandchemistryverydifficult-Tobetterunderstandtheinherentcoordinationchemistryassociatedwiththeactivesite,syntheticanalogsaremostuseful2.Histidine(imidazole)playskeyrolesinthecatalyticfunctionsofalmostallofthemetalloenzymes.Therefore,complexeswithinddazoleligandsareofinterestast…     

耗散量子隧道系统中的形变效应与热库维数的关系

本文利用微扰及变分法研究了耗散量子隧道系统中热库声子波函数的形变效应,发现形变与热库的维数有关。随着维数降低,一方面形变效应增大,另一方面形变效应对量子隧道系统的影响变得更为显著。 关键词：