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排序方式: 共有1942条查询结果,搜索用时 15 毫秒
31.
本文给出一种借助于二维神经网络构成的混合系统,用它来完成几种方向估计算法,这些算法包括:最大似然法,交替投影最大似然法,Marcos等人提出的无需特征分解的“传播算法”。利用神经网络对某些算法的快速性,该系统为实时实现目标的精确定位提供了一条新的,有效的途径。 相似文献
32.
Jafar Zarei 《Expert systems with applications》2012,39(1):68-73
This paper proposes a systematic procedure based on a pattern recognition technique for fault diagnosis of induction motors bearings through the artificial neural networks (ANNs). In this method, the use of time domain features as a proper alternative to frequency features is proposed to improve diagnosis ability. The features are obtained from direct processing of the signal segments using very simple calculation. Three different cases including, healthy, inner race defect and outer race defect are investigated using the proposed algorithm. The ANNs are trained with a subset of the experimental data for known machine conditions. Once the network is trained, efficiency of the proposed method is evaluated using the remaining set of data. The obtained results indicate that using time domain features can be effective in accurate diagnosis of various motor bearing faults with high precision and low computational burden. 相似文献
33.
简介了6000m^3/h空分设备配套的H820.6.1/0.85型离心式空压机轴承结构、润滑系统和运行参数,介绍了轴瓦振裂的现象,并分析了原因,阐述了采取的处理措施、效果以及从中得到的教训。 相似文献
34.
In this paper the influence of core segregations on the formability of workpieces made of bearing steel is analysed and discussed on the basis of compression tests. First the necessary material properties and flow curves, taken at different regions of the bar stock material, were investigated. The core segregation material shows significantly higher flow stress at higher strain rates than the surrounding segregation‐free material. Further a strong influence of the forming temperature on the flow stress was found. On basis of these findings an FEM‐model was developed, that considers the core segregation properties, its shape and position. The results of the compression simulation with this model show a clear impact of the inhomogeneous material properties on the stress distribution. 相似文献
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The need for structural rehabilitation of concrete structures all over the world is well known. Extensive amounts of research have been carried out and are ongoing in this field. Most of the laboratory research has been undertaken on structural elements without live load during the strengthening process. Normally owners of structures want to continue their activity or service during strengthening. Full-scale applications have shown that this is possible, but there is a lack of understanding as to how cyclic loads are distributed during strengthening; for example, traffic loads affect the final strengthening result. This paper presents laboratory tests on concrete beams strengthened with carbon fiber-reinforced polymer laminates and near-surface mounted reinforcement. The beams were subjected to a cyclic load during setting of the adhesive, and after additional hardening were then loaded by deformation control up to failure. 相似文献
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复合地基综合处理的原理探讨 总被引:1,自引:0,他引:1
探讨了深层搅拌或粉喷桩与砂石或石灰桩共同处理软弱土地基的技术,给出了综合处理的计算表达式和实际算例.在实用中,可起到提高承载力和抗液化能力以及应用灵活的作用 相似文献
40.
轴承稳定性对悬臂式烟气轮机振动影响的研究 总被引:2,自引:1,他引:2
针对悬臂式烟气轮机的特点,从轴承稳定性的角度对悬臂式烟气轮机振动特性进行了分析,并具体应用于中原油田炼油化工总厂的烟气轮机中。对该机组启动过程的振动进行了深入的分析,找出了引起联锁停车的原因并提出了具体的解决措施。 相似文献