飞机综合燃油控制系统设计研究

为适应多电/全电飞机发展,根据全电数字化智能燃油综合管理系统发展趋势需求,提出了燃油自动控制系统设计方案,按照其功能分为供油控制系统和质心控制系统,并给出系统结构组成和实现算法,对供油控制,质心位置控制及机动攻击综合控制进行仿真.结果表明系统较好地完成控制目标,便于实现大系统综合,为燃油综合控制系统研究奠定基础并提供研究思路.     

某型飞机供油泵测试装置的设计与实现

简要介绍了某型飞机双端面离心式供油泵的功用、结构和技术标准,在此基础上,进行了总体设计,详细给出了燃油系统的燃油面控制部分的组成和主要特点,利用PLC、平板电脑、智能调节阀技术设计了该装置的自动控制系统,给出了自动控制系统的硬件、软件和操作界面的实现方法。实际应用表明:该测试装置能够满足油面控制和性能的测试要求,测试精度和试验效率高,可靠性强,结构科学合理,操作界面友好。可为产品定期检测、故障诊断和新品装机校验提供有力的技术支持。     

基于压力控制的工业压缩空气供需平衡控制系统的设计及应用研究

针对目前工业压缩空气系统应用中普遍存在的供需不平衡而导致的系统供气压力波动、系统用气负荷与压力互相影响、系统效率降低等问题,设计了一种通过控制并稳定压缩空气系统供气压力进而使压缩空气系统供应和需求达到动态平衡的控制系统,并对其提高整个压缩空气系统运行效率的原理进行了分析.该控制系统在两个不同行业压缩空气系统中应用前后的对比测试试验证明了它在提高压缩空气系统性能中的作用.     

车用电控柴油机喷射系统的控制

柴油机电控技术的发展过程与汽油机电控系统相似。自20世纪80年代开始进入市场的现代汽车柴油机电控系统也是随着控制项目的不断增多，控制任务从简单到复杂，直至全方位控制。早期的电控燃油喷射系统采用“位置控制”。到20世纪90年代初，“时间控制”式电控燃油喷射系统开发成功。到20世纪90年代中期，一种新型的电控共轨式燃油喷射系统问世，抛弃了传统的脉冲高压供油原理，     

专家控制在纸机干燥部通风系统控制中的应用

文章针对纸机干燥部通风系统自动控制的复杂性、排送风量控制中湿度和微差压所具有的强耦合性及常规控制满足不了要求的情况,介绍了专家控制在纸机干燥部通风系统排送风量解耦控制中的实现方法,从理论上证实了该方法的可行性,并通过在实际应用中取得的理想的控制效果验证了该方法的正确性。     

基于变结构预测控制的解耦及其应用

提出了基于变结构预测控制的解耦控制方法,证明了该方法的理论基础,给出了具体的解耦控制算法,并成功应用在橡胶硫化仪温度控制系统中.     

集成激光制造系统的开放式控制研究

针对激光制造系统的发展要求,提出了一种开放式集成激光制造系统,该系统将激光器控制模块、测量模块、机器人模块和计算机控制模块等进行集成,采用模块化设计方法,各模块功能独立,实现了主控计算机对各控制模块的协调控制.其中激光器由PROFIBUS-DP现场总线控制,机器人由运动控制器控制.解决了传统激光制造系统结构封闭,专用性强,难于实现柔性化制造的难题.通过实际应用,进一步证明了该系统的开放性和可控性.     

双模控制在动态控温系统中的应用

文中深入分析ＰＩＤ算法的基础上,结合Ｂａｎｇ－Ｂａｎｇ控制,详细地阐述了双模控制在动态空温系统中的应用,该技术提高了控制速度和系统的稳定度,具有很高的实用价值。     

基于神经网络的通用模型自适应控制

应用复合正交神经网络来实现过程的自适应逆控制方法,和通用模型控制器策略相结合,提出了一种基于神经网络的通用模型自适应控制方法,将非线性过程模型应用逆系统的方法可以在控制算法中直接嵌入过程模型,从而保证通用模型控制策略的可实现性.另一方面,在自适应逆控制中采用复合正交神经网络具有算法简单、学习收敛速度快等优点,可以克服常用的BP和RBF神经网络一些缺点.基于神经网络的通用模型自适应控制方法中的参考轨迹是一条典型的二阶曲线,该控制器参数具有明显的物理意义,参数整定方便.仿真验证了该控制策略的有效性.     

基于模糊监督器的混杂系统控制

针对一类混杂系统的对象,提出了应用多模型控制的方法实现混杂系统控制的思想.借助于模糊监督控制中模糊监督器的设计规则,设计了适用于混杂控制系统的监督控制器,在该监督器的作用下,实现了控制系统中局部控制器之间的切换.仿真结果表明了该设计方法的有效性,被控对象在超调量和调节时间上都具有很好的性能.     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

Limits of topographic measurement by the scanning tunnelling and atomic force microscopes

Parameters describing the topographic character of a surface (height, surface wavelength, slope and curvature) can be derived from equivalent sinusoidal profiles. The response of a surface-measuring instrument may be modelled in terms of instrument parameters such as stylus radius, and scanning range and resolution. The performance of the instrument may then be mapped as a zone in amplitude-wavelength (AW) space to show the sinusoidal profiles it is capable of measuring. In a first-order analysis the STM and AFM are considered as equivalent to contact-stylus instruments with a notional stylus radius equal to the tip radius plus the gap. Comparisons between different instruments and types of instrument are readily made by mapping in AW space. The error arising from convolution of the sinusoidal profile with that of the finite tip may be quantified and plotted as contours in AW space.     

Fractional order nonsingular terminal sliding mode control for flexible spacecraft attitude tracking

This paper investigates a fractional terminal sliding mode control for flexible spacecraft attitude tracking in the presence of inertia uncertainties and extern...     

奥氏体不锈钢表面双辉等离子渗锆的动力学

利用双辉等离子渗金属技术在0Cr18Ni9Ti奥氏体不锈钢表面制备了一层均匀、致密、呈良好冶金结合的渗锆合金层,并对1 060℃下的渗锆动力学进行了研究。结果表明:随着距锆合金层表面距离的增加,锆元素的含量呈梯度递减,扩散系数逐渐减小,而扩散激活能逐步增大;在1 060℃采用双辉等离子技术渗锆时,渗锆合金层表层的空位密度为2.945×(1012~1013)cm-2,与相同温度下采用常规渗金属工艺相比,提高了1~2个数量级。     

气化炉三维扫描测量与数据处理

以德士古气化炉耐火砖的内壁蚀损检测设备为基础,对采集到的点云数据做了进一步处理.通过对数据的筛选和剔除,实现了数据点的平滑降噪细化和精简.然后利用点云对整、网格划分和分色显示等方法,最终完成了内壁腐蚀情况的三维建模.重点讨论了点云数据的预处理及后处理的方法,并根据内壁耐火砖的腐蚀阈值,提出了一种气化炉内壁腐蚀区域的识别与分割方法.对耐火砖的腐蚀分析、气化炉的生产与维修提供了可靠依据,并在工程应用中获得了一致认可.