近红外动脉血液检测中压力对脉搏波的影响

近红外血液检测技术中,透射式光电容积脉搏传感器具有携带有效信息量大的优点,可为动态光谱检测理论提供有效采样数据,但实际应用受到个体差异性的限制.为了克服不同手指端厚度给传感器带来的检测难题,分析了检测结果中压力与直流分量及交流分量之间的关系,通过不同厚度的手指测试实验,指出了存在一个最佳检测区域使得检测到的脉搏波处在最理想状态.     

动态网站自动生成器关键技术研究

该文对动态网站自动生成器进行了研究与分析。通过对动态网站的系统体系结构进行研究,针对三层软件架构下的动态网站设计出相应的代码生成器,并对其中系统实现的关键技术进行分析。     

Discharge properties and chemical stability of SrZrO films

Abstract— MgO thin film is currently used as a surface protective layer for dielectric materials because MgO has a high resistance during ion sputtering and exhibits effective secondary electron emission. The secondary‐electron‐emission coefficient γ of MgO is high for Ne ions; however, it is low for Xe ions. The Xe content of the discharge gas of PDPs needs to be raised in order to increase the luminous efficiency. Thus, the development of high‐γ materials replacing MgO is required. The discharge properties and chemical surface stability of SrO containing Zr (SrZrO) as the candidate high‐γ protective layer for noble PDPs have been characterized. SrZrO films have superior chemical stability, especially the resistance to carbonation because of the existence of a few adsorption sites due to their amorphous structure. The firing voltage is 60 V lower than that of MgO films for a discharge gas of Ne/Xe = 85/15 at 60 kPa.     

Ultra‐fast‐switching flexoelectric liquid‐crystal display with high contrast

Abstract— The flexoelectro‐optic effect provides a fast‐switching mechanism (0.01–0.1 msec), suitable for use in field‐sequential‐color full‐motion‐video displays. An in‐plane electric field is applied to a short‐pitch chiral nematic liquid crystal aligned in the uniform standing helix (or Grandjean) texture. The switching mechanism is experimentally demonstrated in a single‐pixel test cell, and the display performance is investigated as a function of device parameters. A contrast ratio of 2000:1 is predicted.     

Highly efficient switched‐mode transmitter using a current mode class‐D RF amplifier

This article presents a switched‐mode transmitter architecture using a current mode class‐D (CMCD) amplifier. To achieve high average efficiency for a modulated signal the envelope of the complex baseband signal is transformed into pulses such that the CMCD amplifier is operated either at its peak efficiency or completely switched off. The CMCD amplifier has been designed based on single‐tone active harmonic load‐pull measurements to achieve a power‐added efficiency (PAE) of 61.5% with 25 W output power at 900 MHz using LDMOS FETs. Removing the losses of the demodulation filter and of the amplifier a 10% higher efficiency than in an ideal class‐B amplifier can be obtained for burst‐mode operation with a peak‐to‐average power ratio of 10 dB. © 2010 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2010.     

超前瓦斯排放钻孔有效排放半径的测定

介绍了煤层超前钻孔的防突机理,比较和分析了超前瓦斯排放钻孔有效排放半径的3种测定方法,选择钻屑量与钻屑瓦斯解吸指标法进行了现场应用。应用结果表明,使用钻屑量与钻屑瓦斯解吸指标法测定排放钻孔的有效排放半径简便易行,准确可靠。     

纯音听力计中纯音信号发生器的设计与实现

纯音听力计是进行听觉功能测试的基本声学仪器,而纯音信号发生器是其最重要的组成模块,它决定着可控声源的质量,直接影响测试结果的准确性;文章分析了现有纯音信号发生器存在的问题,提出了一种基于微处理器ATMEG128的设计与实现方法;该发生器可生成频率在125Hz~8kHz、听力级为-10~120dB的精密纯音信号;其中,频率按1/3倍频程输出,听力级的最小调节精度可达0.5 dB,符合国家标准。     

高频斩波串级调速系统建模与动、静态特性分析

与传统控制方式不同,斩波串级调速在回路拓扑结构和主回路工作方式上变化较大,因此需要详细分析其调速机理和系统动、静态特性,从而为其工程设计提供理论依据。首先介绍了高频斩波串级调速系统的工作原理,利用状态空间平均法分析了主回路各参量基本输入输出关系,得到了平均状态下的主回路简化数学模型,结合串级调速下负载电流与转矩关系以及异步电动机机电运动方程,得出了高频斩波串级调速系统的简化动态模型,并在此基础给出了系统调速的开环动态结构图,分析了斩波串级调速系统的动、静态特性,为进一步分析系统闭环控制及工程设计提供了理论基础。     

高素质应用型软件服务外包人才培养模式探索

传统的软件人才培养模式存在着知识体系落后,产、学、研脱节等问题。经过几年实践,成都大学形成了"平台+模块+插件"为核心的人才培养课程体系,划分"2+1+1"教学时段,实施校内、校外及创新三维实践教学,对高素质应用型软件服务外包人才培养模式进行了探索。     

基于GA的多路径测试数据生成器适配函数设计

提出了基于GA的多路径测试数据生成的概念和实现方法。讨论了为了实现多路径测试数据生成,设计有效的和高效的适配函数应考虑的因素,用实际案例针对提出的适配函数进行了功能性能验证。结果表明了适配函数设计的有效性。