Multiscale entropy based study of the pathological time series

This paper studies the multiscale entropy （MSE） of electrocardiogram＇s ST segment and compares the MSE results of ST segment with that of electrocardiogram in the first time. Electrocardiogram complexity changing characteristics has important clinical significance for early diagnosis. Study shows that the average MSE values and the varying scope fluctuation could be more effective to reveal the heart health status. Particularly the multiscale values varying scope fluctuation is a more sensitive parameter for early heart disease detection and has a clinical diagnostic significance.     

LED显示屏驱动芯片的应用

介绍了LED显示屏驱动芯片种类及关键参数,并对比了一些LED屏驱动IC的应用方案,总结出各种方案的优缺点,最后对芯片的应用提出了一些建议.     

《国乐大典》第三季的4K制作

随着广播电视技术的发展,近年来4K超高清技术逐渐成为电视技术领域备受关注的焦点.许多电视节目已经使用4K IP制作,同时4K电视机也逐渐普及.基于此,介绍《国乐大典》第三季4K制作的技术特点和亮点,并展望未来4K节目制作的发展.     

An accurate and reliable analysis of trimethylamine using thermal desorption and gas chromatography–time of flight mass spectrometry

Trimethylamine (TMA) is well-known for manifesting the odor of rotting fish and urine. The analysis of TMA in environmental samples generally suffers from low reproducibility and poor sensitivity. In this study, a technique for the quantitative analysis of gas phase TMA was developed using thermal desorption (TD)-gas chromatography (GC)-time of flight mass spectrometry (TOF-MS). This new approach yielded good linearity (R² = 0.9930), precision (RSE = 1.59%), and high sensitivity with the method detection limit (MDL) of 51 pg, i.e., detection of 0.021 ppb of TMA at 1 L sample (limit of detection (LOD): 5.32 pg (0.002 ppb). This method was tested against gas samples collected from two representative sources of TMA: (1) rotten thornback fish and (2) cat urine-soaked clay. The concentration of TMA in these samples, when analyzed after treatment at varying dilution ratios, averaged 293 ± 29.7 ppm (RSE = 3.82%) and 74.1 ± 5.78 ppb (RSE = 3.19%), respectively. The feasibility of this approach, when tested with TD–GC–Quadruple (Q) MS, showed a good compatibility with moderately reduced sensitivity. The results of this study demonstrated that one can achieve highly reliable and reproducible analysis of TMA from environmental samples when using thermal desorption (for pretreatment) and detection (by the TOF or Q-MS system).     

拓扑分子格的ST*分离性公理

由半开元、半拓扑概念出发在拓扑分子格中引入 ST* 分离性公理 ,给出它们的刻画 ,推广文 [2 ]中 T* 分离性公理 ,并得到 ST* 分离性与 T* 分离性之间的关系。     

sST2在脓毒症中的变化及临床意义

目的通过检测脓毒症患儿血液可溶性ST2(sST2)的水平,探讨其在脓毒症中的临床意义.方法采用ELISA法分别检测不同程度脓毒症患儿血液中sST2的水平.同期将健康体检的儿童列为对照组,检测其sST2水平.结果 sST2浓度在脓毒症组为(3.64±0.55)pg/dl、脓毒症伴休克组为(4.38±0.84)pg/dl、脓毒症伴多脏器损害组(7.23±2.18)pg/dl,正常对照组为(1.92±0.67)pg/dl,脓毒症患儿血液中sST2水平与对照组差异有统计学意义(P<0.01),不同程度脓毒症患儿的sST2水平差异也有统计学意义(P<0.01).结论 sST2参与了全身炎症反应的过程,且与疾病的严重程度有关,检测血液中sST2水平可预测脓毒症的严重程度,反映病情变化及预后.     

广义鞍点问题的块三角预条件子

本文对Golub和Yuan(2002)中给出的ST分解推广到广义鞍点问题上,给出了三种块预条件子,并重点分析了其中两种预条件子应用到广义鞍点问题上所得到的对称正定阵,得出了其一般的性质并重点研究了预处理矩阵条件数的上界,最后给出了数值算例.     

基于曲面类型与深度学习融合的三维掌纹识别技术

传统的2维掌纹识别在图像采集时容易受到干湿度、残影和压力等影响,使得其鲁棒性和准确性降低。为解决这些问题,3维掌纹识别技术应运而生。现有的3维掌纹身份认证技术需要将掌纹的特征提取与匹配识别分开进行,不仅延缓了识别时间,更增加了不同方法优化组合的难度。该文提出一种基于曲面类型(ST)与深度学习融合的3维掌纹识别方法。该方法利用ST图像表示3维掌纹特征,并将其作为卷积神经网络(CNN)的输入,实现网络的训练。测试图像可自行提取掌纹图像特征信息并在网络中直接完成识别。实验结果表明,该文方法在公开数据集上得到了99.43%的准确率和28 ms的识别时间,与传统3维掌纹识别方法相比均有提高,实现了3维掌纹的快速高精度识别。     

ST72141K在无刷直流电机无传感器控制系统中的应用

ST72141K是STMicroelectronics公司研制的适用于三相永磁无刷直流电动机的微控制器,用三只电阻器替代霍尔传感器将电动机的三个绕组端电压直接与它连接 ,便可为微控制器提供有关电动机转子位置的信息以实现对电动机的精确控制。文中介绍了ST72141K在无刷直流电动机无传感器控制中的具体应用