基于改进麻雀搜索算法优化BN的变压器故障诊断研究

针对变压器故障诊断准确率低和稳定性差的问题,文中提出了一种改进麻雀搜索算法优化贝叶斯网络的变压器故障诊断方法。首先,通过计算互信息建立最大支撑树并进行定向处理得到贝叶斯网络初始结构即初始种群。然后,在算法中引入一种新的合作机制和正弦余弦算法,提高算法收敛速度和全局搜索能力,并利用油中溶解气体分析,创建基于改进麻雀搜索算法优化贝叶斯网络的变压器故障诊断模型。最后,为了证明所提方法的优越性,将所提的方法与现有变压器故障诊断方法进行对比。结果表明,文中所提出的方法故障诊断率最高,可以更精准地对变压器进行故障诊断。     

数字调幅中波发射机日常维护的路径

考虑群众日常收听需求,数字调幅中波发射机的日常维护与故障处理需加以重视,结合设备日常实际运行情况,详细了解各类故障特点与类型,依据问题研究影响因素,制定相应解决方案与措施,强化设备运行稳定性与安全性,整体状况得到显著提升,能有效促进广播行业可持续发展。     

某通信设备激励模块自检偶发报故的分析与解决措施

简单介绍了某通信设备激励模块工作原理,针对某批次激励模块自检偶发报故的问题,通过对故障原因的详细分析,发现采样时间与指示信号有效时间临界的问题。提出了在充分考虑指示信号有效时间范围的前提下,找到最佳采样时间段,对软件采样时间的设计进行优化的解决措施。     

Fault detection of energy-aware grid systems in big data environment

Grid technology based on parallel theory is used to study a large amount of data processing. This research mainly discusses the fault detection of grid dynamic system in a big data environment. In order to verify the communication efficiency between different security nodes of the ZSS system under different operating system conditions, this study will use four physical computers and VM Ware software to establish a simulated communication environment, using GlobusToolkit (GT)'s existing deployment mechanism to realize the overall grid dynamic deployment architecture. Using Web service technology remotely calls the monitoring module interface of resource nodes in the domain and uses standard protocols to send monitoring data. At the same time, in order for the management node to save the monitoring data in the local standardized form of XML, the administrator can use the saved historical data to process system failures, analyze, and predict system performance. In order to solve the problem of information explosion, a fault detector is used to precisely control the cost of message detection and the state distribution of the detection result and the time of message delay. Under special circumstances, it takes 60 min to execute a 30-min job, and the fault detection point consumes an average of 54.33 min. The research results show that the fault-tolerant strategy can improve the performance of resource consumption in the fault-tolerant tracking system. Adopting the method of dynamically adjustable detection interval can effectively reduce the overhead of the grid dynamic system. The detection method used in this study can meet the application requirements of the grid.     

C-Testable modified-Booth multipliers

In this paper the testability of modified-Booth array multipliers for standard cells based design environments is examined for first time. In such cases the structure of the cells may be unknown, thus Cell Fault Model (CFM) is adopted. Two C-testable designs are proposed. A design for an N _x × N_y bits modified-Booth multiplier, which uses ripple carry addition at the last stage of the multiplication, is first proposed. The design requires the addition of only one extra primary input and 38 test vectors with respect to CFM. A second C-testable design is given using carry lookahead addition at the last stage which is the case of practical implementations of modified-Booth multipliers. Such a C-testable design using carry lookahead addition is for first time proposed in the open literature. This second design requires the addition of 4 extra primary inputs. One-level and two-levels carry lookahead adders, are considered. The C-testable design requires 61 test vectors for the former and 73 test vectors for the latter, respectively. The hardware and delay overheads imposed by both C-testable designs are very small and decrease when the size of the multiplier increases.     

On the generation of test patterns for multiple faults

This article presents a new method to generate test patterns for multiple stuck-at faults in combinational circuits. We assume the presence of all multiple faults of all multiplicities and we do not resort to their explicit enumeration: the target fault is a single component of possibly several multiple faults. New line and gate models are introduced to handle multiple fault effect propagation through the circuits. The method tries to generate test conditions that propagate the effect of the target fault to primary outputs. When these conditions are fulfilled, the input vector is a test for the target fault and it is guaranteed that all multiple faults of all multiplicities containing the target fault as component are also detected. The method uses similar techniques to those in FAN and SOCRATES algorithms to guide the search part of the algorithm, and includes several new heuristics to enhance the performance and fault detection capability. Experiments performed on the ISCAS'85 benchmark circuits show that test sets for multiple faults can be generated with high fault coverage and a reasonable increase in cost over test generation for single stuck-at faults.     

STUDY ON THE DUCTILE DEFORMATION DOMAIN OF THE SIMPLE SHEAR IN ROCKS——TAKING BRITTLE FAULTS OF THE COVERING STRATA IN THE SOUTHERN JIANGSU AREA AS AN EXAMPLE

A study on the ductile deformation domain of the brittle fault in the shallow level ofthe crust is a new probe field for the modern structural geology. Taking the southern Jiang-su Province area as an example the orientation measurement of quartz crystals, the com-positional texture observation of three pressure sensitive minerals and the rheological param-eter determination of dislocation densities, etc. have been demonstrated and analysed basedon typical samples in the present paper. In addition, their generation mechanisms arealso discussed from the cataclastic rheology, the dynamic differentiation and the simpleshearing, specially, from the Ode strength theory. Finally, a generative relationship betweenthe ductile deformation domain of the brittle fault system, in the regional layer--slip andthe formation of the stratabound ore deposit is shown as well.     

Magnetism and structural chemistry of the n=2 Ruddlesden-Popper phase La3LiMnO7

Polycrystalline samples of the n=2 Ruddlesden-Popper phase La₃LiMnO₇ have been prepared and characterized. X-ray and neutron diffraction suggest that the structure is tetragonal with a disordered distribution of Li and Mn cations over the octahedral sites, but ⁶Li MAS NMR shows that the Li and Mn are 1:1 ordered locally. Electron microscopy shows that the stacking of the cation-ordered, perovskite-like bilayers along the crystallographic z-axis is disordered on the distance scale sampled by X-ray and neutron diffraction. Magnetometry data and neutron diffraction data collected at 2 K together suggest that the Mn cations within each structural domain order antiferromagnetically at 14 K, but that the disorder along z prevents the establishment of long-range magnetic order.     

基于故障统一模型的故障检测策略

随着集成电路制造工艺持续向纳米尺度的推进,数字电路受老化、工艺误差、软错误等故障所造成的时序偏差越发突出,严重威胁了电路的“时序安全”。文中通过分析故障影响信号稳定性侵犯模型,提出了一种新的故障检测模型。该模型扩展了现有的故障检测能力,通过使用C单元作为稳定性检测器输出单元,提高了其对高速的适应性。仿真结果显示,与已有结果相比其具有明显的速度优势和较小的硬件开销。     

迷你音箱组装常见故障分析与处理

组装迷你音箱是大学必修课《电装实习》课程的重要内容之一,基于提高学生在实习中自主完成任务的能力,切实提高大学生实践动手能力。根据多年带该课程的体会将个人的一点认识、故障分析与处理汇总,分析了迷你音箱的基本工作原理,介绍了组装过程,最后详细罗列了迷你音箱可能出现的各种故障,并提供了切实有效的解决方法。经过实践验证,这些故障分析与处理方法大大提高了实习效率,也为电子组装爱好者提供了解决此类问题的保障。