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<正> LQ—1600K打印机传动系统包括字车横移系统、输纸系统和色带传动系统。下面就字车横移系统和输纸系统进行分析,色带传送系统比较简单,不再叙述。 字车横移与输纸系统 LQ—1600K打印机字车横移系统由CR步进电机、传动机构和字车托架等零部件组成(见图1)。首先,在打印之前,接通电源驱动CR电机,使字车传动机构进行横移运动。当初始位置传感器检测到字车初始位置信号时反馈到CPU,由CPU比较和处理,使字车置于初始位置,完成字车复位操作。其次,当字车完成横移寻 相似文献
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文章分析了动态环境下多普勒频移的产生,研究了多普勒频移的估算方法并建立了数学模型,在此基础上提出了一种运用DSP结合专用的DDS芯片AD9954模拟多普勒频移的方案。并根据所模拟数据的要求选择了一种可行AD9954的工作模式,介绍了参数的计算方法,给出了DSP控制AD9954进行多普勒频移模拟的程序流程。 相似文献
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从电子竞标系统的需求出发,对当前各种评标方法进行综合分析,采用了模糊评标的算法思想,建立了评标指标体系,用数学模型进行分析计算,确定最佳的投标人. 相似文献
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随着电传操纵系统在现代飞机上的广泛应用,其动力学特性也越来越复杂。如果驾驶员的操纵与飞机性能及其外部环境不协调,则人机闭环系统稳定性下降,严重时会出现一种非期望的,不符合驾驶员意愿的闭环耦合振荡,直接影响到飞行安全,这种现象称为驾驶员诱发振荡。针对驾驶员操纵诱发横航向振荡问题,本文建立了横航向驾驶员-控制器-飞机本体组合系统的数学模型,研究驾驶员模型中诱发横航向振荡的关键参数。以空客A300飞机横航向模型进行闭环仿真分析,给出各个参数对横航向PI0的影响特性,分析结果对工程实践具有一定的指导意义。 相似文献
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随着电传操纵系统在现代飞机上的广泛应用,其动力学特性也越来越复杂。如果驾驶员的操纵与飞机性能及其外部环境不协调,则人机闭环系统稳定性下降,严重时会出现一种非期望的,不符合驾驶员意愿的闭环耦合振荡,直接影响到飞行安全,这种现象称为驾驶员诱发振荡。针对驾驶员操纵诱发横航向振荡问题,本文建立了横航向驾驶员-控制器-飞机本体组合系统的数学模型,研究驾驶员模型中诱发横航向振荡的关键参数。以空客A300飞机横航向模型进行闭环仿真分析,给出各个参数对横航向PIO的影响特性,分析结果对工程实践具有一定的指导意义。 相似文献
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本文对升降横移式立体停车库的不同控制形式进行了研究,分析了继电器控制方式、单片机控制方式和可编程逻辑控制器PLC控制方式的优缺点。研究结果表明,采用可编程逻辑控制器PLC控制方式的升降横移式立体停车库具有结构紧凑、可靠性强和抗干扰能力高等优越性能,可作为升降横移式立体停车库比较理想的控制方式。 相似文献
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A single-loop fourth-order sigma-delta (∑△) interface circuit for a closed-loop micromachined accelerometer is presented.Two additional electronic integrators are cascaded with the micromachined sensing element to form a fourth-order loop filter.The three main noise sources affecting the overall system resolution of a ∑Δ accelerometer,mechanical noise,electronic noise and quantization noise,are analyzed in detail.Accurate mathematical formulas for electronic and quantization noise are established.The ASIC is fabricated in a 0.5 μm two-metal two-poly n-well CMOS process.The test results indicate that the mechanical noise and electronic noise are 1 μg(Hz) and 8 μV/(Hz)respectively,and the theoretical models of electronic and quantization noise agree well with the test and simulation results. 相似文献
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描述了电子对抗各单元在组网协同条件下的主要工作及行为特征,在计算机上用其数学模型表征的系统表示此过程。在展望未来一体化信息作战的需求背景下,设计了一种应用于电子对抗领域的组网软件仿真系统,建立了其电子对抗系统各主要作战单元的仿真模型以及空间电磁环境传播模型,对侦察、干扰等站型布站和工作过程进行了仿真,对组网仿真实现方法进行了分析,并给出了设计实例。 相似文献
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Non linear electronic systems are described by non linear differential equations systems. These equations are solved with exactness by using formal computation and a new method based on the theory of non commutative power generating series. All the results are given as analytical expressions. This particularity allows us to represent any non linear electronic system by a mathematical model characterized by the non commutative power generating series associated with the output signal of the system. We can obtain the model of a new circuit made up by two circuits when we know their models. The power generating series of this new system is equal to the composition of the generating power series of the two first circuits. This mathematical model allows us to simulate more easily complex systems made up by several more simple circuits. 相似文献
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红外焦平面探测器非均匀性的简化数学模型 总被引:3,自引:0,他引:3
红外焦平面探测器非均匀性对红外成像系统的性能产生很大的影响,本文主要讨论了
对非均匀性进行校正各种数学模型,详细分析了电噪声的作用,并对各种模型的适用范围进行了讨论。 相似文献
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V. V. Krapukhin V. G. Kosushkin L. V. Kozhitov V. G. Kostishin D. G. Muratov A. V. Popkova 《Russian Microelectronics》2017,46(8):571-579
The results of creating a system of models and algorithms for calculating the parameters of technological processes for obtaining materials of micro- and nanoelectronics and designing equipment are considered. It is shown that the distinctive feature of the teaching methods for special technological courses in electronic engineering materials is the construction of courses by analogy with the technological processes for obtaining materials for electronics: from a bulk single crystal to instrumental structures, whose dimensions do not currently exceed several tens of nanometers. A scientific model approach to the solution of technological problems was formed in the study of heat and mass transfer processes, which together with the processes of interaction in liquids and gas, taking heterogeneous reactions into account, are the theoretical basis of the technology of electronic engineering materials. The possibilities of physical and mathematical modeling are compared. Approaches to create mathematical models of the growth processes of single crystals of semiconductors, epitaxial layers, and heterostructures are considered and the possibilities of their practical use are determined. It is determined that the ideas proposed by V.V. Krapukhin at the initial stages of training specialists in the field of the technology of electronic material and developed by his students identified the possibility of training several generations of qualified specialists. 相似文献
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EPS用机械转向器是实现汽车转向的主要部件之一,为保证车辆的安全性,需要了解其耐冲击性能。机械转向器冲击试验台主要用于对机械转向器的冲击试验。文中针对试验台的阀控非对称缸电液力控制系统进行了研究。通过对控制系统的各个环节的分析,建立各环节的数学模型。进而得到以力为控制量的电液伺服系统数学模型,并利用Simulink仿真平台对系统进行频域和时域分析。分析结果表明,试验台液压系统闭环稳定,满足性能要求。 相似文献
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Failure mechanism models for plastic deformation 总被引:1,自引:0,他引:1
A tutorial illustrating designs in which plastic deformation can endanger system performance, thereby acting as an overstress failure mechanism, is presented. Analytic methods, based on continuum mechanics, are presented to design against such failures. Examples illustrate the use of these models in practical designs encountered in mechanical systems and in electronic packaging 相似文献
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Failure-mechanism models for creep and creep rupture 总被引:1,自引:0,他引:1
This tutorial illustrates design situations where creep and creep rupture of components can compromise system performance over time, thereby acting as a wearout failure mechanism. Polycrystalline materials, such as metals and ceramics, and polymers are treated. Analytic microstructural creep mechanisms leading to failure of these materials are presented. Continuum microscale models for predicting long-term creep are explained for practical design purposes. Two examples illustrate these models for mechanical engineering and electronic packaging situations 相似文献