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61.
针对某型俄制机载产品的测试需求,提出了一种ГОСТ18977总线发送卡的设计方法;介绍了ГОСТ18977总线标准和80C196KB单片机、EPM7128LC可编程逻辑器件的使用方法,并利用外围电路和上述芯片设计并实现ГОСТ18977总线发送卡,介绍了并口EPP模式下ГОСТ18977总线数据的控制过程,给出了ГОСТ18977总线发送卡的部分设计电路,并阐述了它的设计原理;实践验证了该板卡能够完成ГОСТ18977总线数据信息格式转换和传输,完全可以满足对某型俄制机载产品性能检测的要求。  相似文献   
62.
In this paper, we consider a model for the dynamic multiple-fault diagnosis (DMFD) problem arising in online monitoring of complex systems and present a solution. This problem involves real-time inference of the most likely set of faults and their time-evolution based on blocks of unreliable test outcomes over time. In the DMFD problem, there is a finite set of mutually independent fault states, and a finite set of sensors (tests) is used to monitor their status. We model the dependence of test outcomes on the fault states via the traditional D-matrix (fault dictionary). The tests are imperfect in the sense that they can have missed detections, false alarms, or may be available asynchronously. Based on the imperfect observations over time, the problem is to identify the most likely evolution of fault states over time. The DMFD problem is an intractable NP-hard combinatorial optimization problem. Consequently, we decompose the DMFD problem into a series of decoupled subproblems, one for each sample epoch. For a single-epoch MFD, we develop a fast and high-quality deterministic simulated annealing method. Based on the sequential inferences, a local search-and-update scheme is applied to further improve the solution. Finally, we discuss how the method can be extended to dependent faults.  相似文献   
63.
基于CPLD的ГOCT18977总线发送卡设计   总被引:1,自引:0,他引:1  
针对某型俄制机载产品的测试需求,提出了一种ГOCT18977总线发送卡的设计方法介绍了ГOCT18977总线标准和80C196KB单片机、EPM7128LC可编程逻辑器件的使用方法,并利用外围电路和上述芯片设计并实现ГOCT18977总线发送卡,介绍了并口EPP模式下ГOCT18977总线数据的控制过程,给出了ГOCT18977总线发送卡的部分设计电路,并阐述了它的设计原理;实践验证了该板卡能够完成ГOCT18977总线数据信息格式转换和传输,完全可以满足对某型俄制机载产品性能检测的要求.  相似文献   
64.
磁性材料是一种重要的刺激响应材料,可通过外部磁场穿透组织和器官实现无线远程控制,具有生物兼容性高、磁场控 制简单和调控速度快等特点,广泛应用于医疗机器人、人造器官、生物化学合成和药物递送等生物医学领域。 复杂的工作场景 和多功能需求对磁性材料的精确控制提出了更高的要求,从基于磁力的简单平面驱动,到基于磁力和磁力矩的复杂空间驱动; 从基于材料本身运动变形进行功能实现到作为多功能柔性电子器件载体实现更复杂的环境检测等。 本文介绍了几种常用磁性 材料的磁学特性、磁场控制平台和磁极编程技术,并展示了磁性液体、磁性块体和磁性薄膜 3 种不同形态磁性材料在生物医学 领域的应用进展和面临的诸多挑战,最后对未来的发展趋势进行了展望。  相似文献   
65.
66.
本文结合单位实际检测工作,依据JJG746-2004《超声探伤仪》计量检定规程,对超声探伤仪的水平线性误差测量不确定度进行了评定。  相似文献   
67.
The reaction mechanisms and microstructures of various layered nano‐thermite composites are investigated through characterization of their energetic properties. Migration of reactive components across the reaction zone is analyzed, which plays an important role in determining the process initiation, reaction propagation, and chemical stability at low temperatures. Distinct types of nanoparticles are deposited onto filter paper in a sequence, using the vacuum filtration method, which promotes intimate contact between neighboring reactive layers. Scanning Electron Microscopy (SEM) images demonstrate a well‐defined contact region between the two layers in the Al/CuO or Al/NiO composites. Differential Scanning Calorimetry (DSC) data shows that the thermite reaction occurs below the melting temperature of Al, resulting in rapid heat release, and improves reaction initiation. Elemental mapping results reveal the migration of Al, Ni/Cu, and oxygen before and after the thermite reaction, which is arranged during thermogravimetric analysis (TGA). This analysis indicates the dominant pathway of the thermite reaction in each composite, through either decomposition of the CuO nanoparticles in the Al/CuO composite or through direct migration of reactive components across the conducting surface within the Al/NiO composite.
  相似文献   
68.
As multiple {112¯ 2} twin variants are often formed during deformation in hexagonal close-packed (hcp) titanium, the twin-twin interaction structure has a profound influence on mechanical properties. In this paper, the twin-twin interaction structures of the {112¯2} contraction twin in cold-rolled commercial purity titanium were studied by using electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). Formation of the {112¯2} twin variants was found to deviate the rank of Schmid factor, and the non-Schmid behavior was explained by the high-angle grain boundary nucleation mechanism. All the observed twin-twin pairs manifested a quilted-looking structure, which consists of the incoming twins being arrested by the obstacle twins. Furthermore, the quilted-looking {112¯2} twin-twin boundary was revealed by TEM and high resolution TEM observations. De-twinning, lattice rotation and curved twin boundary were observed in the obstacle twin due to the twin-twin reaction with the impinging twin. A twin-twin interaction mechanism for the {112¯2} twin variants was proposed in terms of the dislocation dissociation, which will enrich the understanding for the propagation of twins and twinning-induced hardening in hcp metals and alloys.  相似文献   
69.
Rolling texture and its effect on tensile properties of Ti60 alloy plates were investigated in the present study. The plates wereβ-rolled at 1070℃ and(α+β)-rolled at 980℃, using uni-directionally rolling(UDR) and cross-directionally rolling(CDR) processes, respectively.β-rolled plates exhibited weak textures, which were attributed to the dispersive orientations of secondary α during the β→α phase transformation. Strong deformation textures formed in(α+β)-rolled plates as a result of slipping mechanisms: the strong T-type texture in UDR plate was related to {10 1 0}[11 2 0] slipping, while the B-type texture in CDR plate was relevant with {0001}[11 2 0] slip. Strong T-type textures led to anisotropic tensile properties. B-type textures would decrease such an anisotropy. The(α+β)-CDR process was found to be a candidate process for reducing anisotropy of Ti60 alloy plates.  相似文献   
70.
金王平  李鹏飞  韦穗  梁栋 《计算机工程》2010,36(19):208-209,212
针对多通道的图像分割提出一种新的活动轮廓线提取算法。对轮廓线长度采用Munford-Shah最小化泛函加上图像每个通道上的拟合误差之和。与传统C-V方法类似,该算法不需要图像的梯度信息就可以检测物体的边缘,解决了传统C-V方法不管从哪个尺度空间都无法完全分割彩色图像中物体的问题。并通过改进初始化函数提高了分割的速度。  相似文献   
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