基于CPLD的ГOCT18977总线发送卡设计

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.     

液位计标准装置中激光干涉仪测量值的不确定度分析

近年来,随着石油化工行业的蓬勃发展,基于不同测量原理的液位计产品在储罐液位测量中的应用也日趋广泛。同时,准确度等级高液位计在石油产品的工业计量中发挥着重要作用,在法制计量中占有重要地位。因此,对液位计产品建立统一的评判标准和性能实验方案变得日益迫切起来。为能够准确地衡量液位计的性能,依托我单位液位计国家型式评价实验室,建立了一套液位计标准装置,本文将对标准装置中激光干涉仪测量结果的不确定度进行分析。     

Diversity in Addressing Reaction Mechanisms of Nano‐Thermite Composites with a Layer by Layer Structure

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.

     

Interaction of {112¯2} twin variants in hexagonal close-packed titanium

As multiple {11$\overline{2}$ 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 {11$\overline{2}$2} contraction twin in cold-rolled commercial purity titanium were studied by using electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). Formation of the {11$\overline{2}$2} twin variants was found to deviate the rank of Schmid factor, and the non-Schmid behavior was explained by the high-angle grain boundary nucleation mechanism. All the observed twin-twin pairs manifested a quilted-looking structure, which consists of the incoming twins being arrested by the obstacle twins. Furthermore, the quilted-looking {11$\overline{2}$2} twin-twin boundary was revealed by TEM and high resolution TEM observations. De-twinning, lattice rotation and curved twin boundary were observed in the obstacle twin due to the twin-twin reaction with the impinging twin. A twin-twin interaction mechanism for the {11$\overline{2}$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.     

Rolling texture and its effect on tensile property of a near-α titanium alloy Ti60 plate

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.     

Predicting protein secondary structure using a mixed-modal SVM method in a compound pyramid model

Accurate protein secondary structure prediction plays an important role in direct tertiary structure modeling, and can also significantly improve sequence analysis and sequence-structure threading for structure and function determination. Hence improving the accuracy of secondary structure prediction is essential for future developments throughout the field of protein research.In this article, we propose a mixed-modal support vector machine (SVM) method for predicting protein secondary structure. Using the evolutionary information contained in the physicochemical properties of each amino acid and a position-specific scoring matrix generated by a PSI-BLAST multiple sequence alignment as input for a mixed-modal SVM, secondary structure can be predicted at significantly increased accuracy. Using a Knowledge Discovery Theory based on the Inner Cognitive Mechanism (KDTICM) method, we have proposed a compound pyramid model, which is composed of three layers of intelligent interface that integrate a mixed-modal SVM (MMS) module, a modified Knowledge Discovery in Databases (KDD1) process, a mixed-modal back propagation neural network (MMBP) module and so on.Testing against data sets of non-redundant protein sequences returned values for the Q₃ accuracy measure that ranged from 84.0% to 85.6%,while values for the SOV99 segment overlap measure ranged from 79.8% to 80.6%. When compared using a blind test dataset from the CASP8 meeting against currently available secondary structure prediction methods, our new approach shows superior accuracy.Availability: http://www.kdd.ustb.edu.cn/protein_Web/.     

磁敏测速系统的数据采集平台实现

串口同步采集是工业控制应用的重要环节,为克服由于不准确的数据采集所带来的乘性误差,进而对多串口的同步采集进行了研究。利用VS2005编程环境,设计实现了多串口的上位机数据采集平台,该平台开辟线程对多个串口采取重叠读取方式,实现了对测速系统中大量的串口数据同步读取、保存并实现波形动态显示的功能,满足了智能测速系统的测速算法研究的需要。此平台可以广泛的应用在测速系统之中,也可辅助用于各种工业控制的高级要求。     

基于Browse/Web/DBMS Server的人才管理系统

该文应用IBM推出的新技术设计实现了一种3层C／S原型系统即Browse／Web／DBMSServer,并应用这种原型系统实现了一个具有良好动态特性和交互动能的网上人才管理系统。Browse／Web／DBMSServe原型系统还可应用于其他信息系统。     

图像逆映射与融合技术

对图像逆映射与融合技术作了系统研究.通过把图像映射关系统一为位移场表示,详细讨论了消除图像缝隙的逆映射算法.给出了多张图像的迭代融合算法.实验表明,混合使用图像逆映射算法和迭代融合算法可以获得满意的结果.