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991.
Liang Yong-chao Ma Rui-bo Zhou Li-li He Mu Tian Ze-an Mo Yun-fei 《Journal of Superconductivity and Novel Magnetism》2021,34(12):3377-3383
Journal of Superconductivity and Novel Magnetism - A molecular dynamics simulation has been conducted in Ni73Co27 and Ni74Co26 alloys during rapid solidification at the cooling rate of... 相似文献
992.
993.
Qibing Jin Zeyu Wang Wu Cai Yuming Zhang 《International Journal of Adaptive Control and Signal Processing》2021,35(5):811-827
In this paper, the parameter estimation issue of Wiener system with random time delay and missing output data is studied. The linear part of Wiener system is described by Finite Impulse Response (FIR) model. The mathematical formula of the Expectation Maximum algorithm to identify Wiener-FIR system that contains the random time delay and the nonlinear output data in missing completely at random mechanism is derived, which is never considered before. To obtain the unmeasurable intermediate variable in Wiener-FIR system, the idea of auxiliary model is adopted. The time delay and system parameters can be estimated simultaneously by this method. Numerical example and the identification of water tank system example are carried out, the effectiveness of the algorithm is proved. 相似文献
994.
995.
S.P. Mo D.A. Axinte T.H. Hyde N.N.Z. Gindy 《Journal of Materials Processing Technology》2005,160(3):382-389
Despite the fact that broaching has been used for long a time as a machining process for manufacturing highly accurate, complex profiles, little work has been published on the selection of cutting conditions to maximise tool life while achieving the required surface quality and level of cutting forces. This is even more important when notorious difficult-to-cut materials, such as Ni and Ti alloys, used in the aero-engine/power generation industry where high geometrical accuracy, along with restricted surface quality are required. The paper describes a multi-step methodology to select the cutting conditions for the broaching of Ni and Ti alloys used in the manufacture of aero-engines and power generators. Based on the application of the Taguchi technique, the cutting conditions (cutting speed, rise per tooth, rake angle, coolant type) were selected in order to obtain fine surface quality along with reasonably low levels of main cutting force (Fz) and perpendicular cutting force (Fy). This was followed by a reduced number of tool life tests which were carried out in order to select the final cutting conditions. Scanning electron microscopy (SEM) and chemical composition analysis on the flank and rake faces of the tools were employed to characterise the worn tools. It was found that when broaching forces, surface roughness and tool life are considered as process output measures, and taking into consideration generic process constraints on process productivity, machine tool stability, and tool stiffness, only a “pseudo-optimal” solution for the cutting conditions could be specified. 相似文献
996.
现场补口涂层作为整个涂层体系非常重要的一部分,应与管道主体防腐涂层结构具有很好的相融性,但现场补口施工其补口工艺控制的难度比在工厂内预制要大得多。有时不能完全达到理想状态。因此,要对现场补口方法进行研究。本文针对上述问题介绍了大庆油田建设集团工程设计研究院在“防腐管道现场整体喷涂补口技术”研究中的喷涂3PE粉末涂料补口技术、PE防腐管道喷涂聚脲补口技术和管道补口工程车。 相似文献
997.
998.
This paper deals with the problem of robust H∞ fault detection for a class of stochastic Markovian jump systems (SMJSs) The aim is to design a linear mode-dependent fault detection filter such that the fault detection system is not only stochastically asymptotically stable in the large, but also satisfies a prescribed H∞-norm level for all admissible uncertainties. By using Lyapunov stability theory and generalized Itô formula, some novel mode-dependent and delay-dependent sufficient conditions in terms of linear matrix inequality (LMI) are proposed to insure the existence of the desired fault detection filter. A simulation example and an industrial nonisothermal continuous stirred tank reactor (CSTR) system are employed to show the effectiveness of the proposed method. 相似文献
999.
1000.