影响功率MOSFET开关速度的因素分析

给出了功率ＭＯＳＦＥＴ的等效电路模型，详细分析了栅极驱动电路和功率输出负载对功率ＭＯＳＦＥＴ开关速度的影响，并给出了实用的栅极驱动电路。     

利用快速傅里叶变换技术提高质谱计的分辨率

本文给出了一个应用快速傅里叶变换技术（ＦＦＴ）提高质谱计分辨率的方法。     

面向并行工程的DFC与CTC辨析

对面向成本的设计和按费用设计的思想进行了分析，指出ＤＦＣ与ＤＴＣ的不同之处主要在于：ＤＦＣ是一种设计方法，ＤＴＣ在很大程度上属于管理方法；ＤＦＣ主动地运用各种方法降低产品的成本，而ＤＴＣ是为了获得一个满足给定的目标成本并符合用户要求的设计。     

用几何象差计算几何传递函数

本文简要介绍了物理传递函数（ＯＴＦ）及几何传递函数（ＧＯＴＦ）的区别。几何传递函数的修正方法。推导出用几何象差计算几何传递函数的公式。并给出计算实例。     

纯虚乘子FFT的最快速算法

本文定义了四种类型的ＤＦＴ（即ＤＦＴ一ｊ，ｊ＝Ⅰ，Ⅱ，Ⅲ，Ⅳ），探讨了四种ＤＦＴ之间的联系以及其固有特性，由此提出了适合于长度Ｎ＝２ｍ所有四种类型ＤＦＴ的纯虚乘子最快速算法。文中导出了用Ｋｒｏｎｅｃｋｅｒ直积与直和形式表示的算法公式；以长度Ｎ＝２３为算例给出了信号流图；分析了算法的运算量，并与传统的基２算法、基４算法以及现有的其它三种纯虚乘子ＦＦＴ算法进行了比较。结果表明，本文提出的算法所需运算量最少，用纯虚数作乘子，可进行原位计算，结构简单规则，易于实现。本文算法己用软件实现，并在实际中得到应用。     

高齿准双曲面齿轮的研究

研究基于局部综合法的高齿准双曲面齿轮ＨＦＴ法切齿参数的设计,给出用ＨＦＴ法加工准双曲面齿轮副的齿面接触分析方法,并在此基础上,比较了普通齿和高齿２种准双曲面齿轮副的传动误差曲线和啮合区。结果表明,高齿准双曲面齿轮副具有较好的啮合性能。     

回扫变压器高压振铃比微机自动测试电路

１前言电视机回扫变压器（简称ＦＢＴ）是电视机的关键部件，用于给显像管提供数万伏高压。据统计ＦＢＴ失效是造成电视机失效的主要原因之一，所以加强ＦＢＴ的检测分析手段是提高和保证产品质量的有效措施。ＦＢＴ工作时产生的振铃现象是由于自身分布参数引起的高频寄生...     

提高FFT谱质量的一种新方法

论述了ＤＦＴ连续性,并推出ＤＦＴ谱的插值公式。提出了通过迭代确定ＤＦＴ的幅值极大值以寻找信号参数,并编制出寻找ＤＦＴ幅值峰值的抛物线迭代程序,该迭代只需几步即可得到相当准确的频率。考察了ＤＦＴ的频率分辨力和精度。比较了窗函数对ＤＦＴ精度影响,指出全景分析时采用汉宁窗,而局部分析时采用矩形窗。     

Poincare变换——一种判定机械故障的新方法

机械故障的判定常采用的是基于ＦＦＴ分析的方法，但其对非线性情形效果不理想，本文从非线性理论出发提出了一种判定故障的新方法，实践证明是成功的。     

智能电平衡分析测试仪

本文介绍了智能电平衡分析测试仪的测量原理、微机硬件和软件的实现方法，并给出了实验测试结果。根据复序列的快速富里叶变换（ＦＦＴ）原理，推导出测试所需的计算方法。     

Optimal control of a single link manipulator including motor dynamics

The nonlinear behavior of robotic manipulators motivated the research in implementing adaptive control strategies. Recently, the effects of motor dynamics have attracted the attention of a number of researchers. In this paper, we present a new optimal controller designed for rigid-body robots including motor dynamics. The new optimal adaptive controller developed in this work is based on feedback linearization, it does not require acceleration feedback, it does not assume full state is available for measurement but it requires an observer. Naturally, it does not assume exact knowledge of either robot or actuator parameters. The optimality is based on the minimization of a performance index which turns out to be possible if we could find a solution to the Hamilton-Jacobi equation.     

A frequency-selective system for stabilizing the diode-laser radiation power without operating-point shift

A bandpass-disturbance suppression system that does not shift the operating point owing to the frequency selectivity in the range of enabling the negative feedback is described. The feedback does not apply to the zero-frequency range. An arising contradiction between the requirements of the response speed and the degree of noise suppression is considered, and methods for solving this problem are presented.     

MATLAB＋FPGA的红外图像处理与接收

本设计作为红外模拟靶标系统的一部分。主要实现基于MAT-LAB红外图像的读取与灰度值转化。并将图像灰度值通过串口发送给FPGA控制系统,对数据传输速率要求不高,传输距离也不要求很长。但传输数据要求准确可靠。     

垃圾气化消解技术研究

根据我国目前城市垃圾热值偏低、垃圾成份混杂、可回收利用率低的实际情况,我们提出利用厌氧反应的消解气化法处理垃圾,不增添任何辅助燃料,不直接对外排放,不要求可燃物的粒度、块度,而且采用气化消解技术兼有焚烧的各项优势,同时在排放问题上和能源利用上有了长足的发展,可大幅度降低运行成本,减少处理工作量,形成新能源,符合国情。通过垃圾整个工艺过程的处理,城市垃圾完全达到了“三化”的处理目的,是目前最好的处理方式。     

Wear resistance of plasma-hardened materials

The article contains information on the wear resistance of manually plasma-hardened low-carbon rail and structural steels and cast iron during tests on a friction machine and in full-scale operation. It is established that plasma hardening improves the wear resistance effectively, including that of low-carbon steel that does not harden under heating in a furnace. The process does not provoke any accelerated wear of the counterbody.     

Synthesis of rational tooth profiles for plane gear transmissions

The line of engagement, which does not vary during operation, has been determined via solving the variation problem. It is found that the obtained line of engagement does not move off the pitch point, and it is the arc of circle. The optimal teeth profiles consisting of two segments: the convex segment at pinion tip and of concave segment at the dedendum has been obtained.     

复杂时变环境高速开关阀自适应控制算法

为满足高速开关阀在复杂时变环境下的控制需求,通过数学模型分析,提出阈值占空比自学习的高速开关阀自适应控制算法。自学习阶段,通过自学习方波自适应调整阈值占空比,满足复杂时变环境控制需求;压力控制阶段,采用混合脉宽激励——“积分+斜率”控制算法,在缩短压力响应时间的同时,减少动态调节时的超调量。实验验证表明,在不同环境温度下,方波跟随响应时间不超过350 ms,超调量不超过0.25 MPa,稳态误差不超过0.1 MPa;1 Hz正弦波动态跟随性能良好,因此高速开关阀自适应控制算法在复杂时变环境中具有良好的自适应和鲁棒性。     

Determining local wear equation based on friction and wear testing using a pin-on-disk scheme

Based on pin-on-disk friction and wear testing, the parameters of the wear rate as a function of sliding velocity and pressure with account for their distribution over the contact spot are computed. The parameters are compared to those obtained assuming a uniform distribution of velocities and pressures. It is assumed in the work that the contact spot does not vary, the disk does not wear out, and the study is carried out under steady-state wear conditions.     

齿条型刀具基本齿廓的改进

为提高外啮合渐开线圆柱齿轮的齿根弯曲强度 ,针对齿条型刀具提出了减小刀具齿顶高并同时加大其齿顶过渡圆弧半径的改进方案。确定了在保证齿轮工作时不发生过渡曲线干涉且不改变齿轮有效齿面的前提下刀具的最小齿顶高系数 ,并建议在齿轮刀具标准中增加刀具齿顶高系数系列。     

A simple chamber for observing microscopic specimens in both top and side views

A method is described which permits the observation of microscopic specimens in both top and side views, a rapid change between the two views being possible without disturbing the specimen. The system requires the introduction of simple optical components into a culture chamber, does not restrict the types of microscopy that may be used, and does not necessitate modification of the microscope itself. The technique is discussed in relation to the study of tissue cells in culture, but may find applications in other areas.