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21.
中子管是一种用途广泛的关键部件,然而目前国产中子管的可靠性水平与国外相比还有一定差距,难以满足各行业的使用需求。本文分析了中子管的主要故障模式,采用模糊综合评判和层次分析法对中子管故障进行了多级模糊综合评判,并对中子管故障风险进行了评估。结果表明,中子管总体故障风险水平中等,故障风险前3位的部件为靶、氘氚储存器和加速极,在设计和使用中应重点关注靶释放氦气,靶膜氧化,氘氚储存器吸气剂局部破损,绝缘瓷管破损,加速极离子加速、聚焦不稳定等故障。  相似文献   
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王娇  李琦  高军萍  李怡  王彤 《信息与控制》2019,48(3):279-284
提出一种MIMO雷达相位编码信号集设计方法,该方法对飞蛾扑火优化算法进行改进,利用改进的飞蛾扑火算法优化相位编码信号集,提高其正交性.在改进方法中,增加对火焰的更新过程,使火焰不仅能够保存最优飞蛾位置还具有搜索最优解的功能.优化过程以自相关函数旁瓣峰值和、互相关函数峰值和,以及自相关函数旁瓣能量、互相关函数能量作为算法适应度函数.仿真实验结果表明,改进方法明显提高了飞蛾扑火优化算法的收敛速度和收敛精度,且优化得到的信号集具有较低的自相关旁瓣值和互相关值.  相似文献   
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A Takagi-Sugeno adaptive neuro-fuzzy inference system (TSFIS) model is developed and applied to a dataset of wellhead flow-test data for the Resalat oil field located offshore southern Iran, the objective is to assist in the prediction and control of multi-phase flow rates of oil and gas through the wellhead chokes. For this purpose, 182 test data points (Appendix 1) related to the Resalat field are evaluated. In order to predict production flow rate (QL) expressed as stock-tank barrels per day (STB/D), this dataset includes four selected input variables: upstream pressure (Pwh); wellhead choke sizes (D64); gas to liquid ratio (GLR); and, base solids and water including some water-soluble oil emulsion (BS&W). The test data points evaluated include a wide range of oil flow rate conditions and values for the four input variables recorded. The TSFIS algorithm applied involves five data processing steps: a) pre-processing, b) fuzzification, c) rules base and adaptive neuro-fuzzy inference engine, d) defuzzification, and e) post-processing of the fuzzy model. The developed TSFIS model for the Resalat oil field database predicted oil flow rate to a high degree of accuracy (root mean square error = 247 STB/D, correlation coefficient = 0.9987), which improves substantially on the commonly used empirical algorithms used for such predictions. TSFIS can potentially be applied in wellhead choke fuzzy controllers to stabilize flow in specific wells based on real-time input data records.  相似文献   
26.
王飞  齐海峰  李靖 《轧钢》2018,35(5):58-60
宽展是冷连轧机切边剪切边宽度设定的重要考虑因素。影响宽展的因素较多,若考虑各影响因素,建立宽展模型十分困难。为此,在满足生产需求的前提下,通过大量数据分析,拟合出宽展系数计算多项式,进而可计算出满足需求的考虑宽展的切边剪宽度设定值,并通过自动化系统的改造实现了切边剪宽度的自动设定。  相似文献   
27.
Calculation of interfacial tension during bitumen production is a crucial issue in heavy crude oil history. Upon variation in pressure, temperature and phases composition, interfacial tension between bitumen and water change. In this work a sophisticated method called subtractive clustering was utilized to predict dynamic interfacial tension between bitumen and water. The subtractive clustering method is composed of optimized fuzzy logic algorithm. A data bank which is collected from open-source literature, is used to create a reliable model. Then the prediction accuracy of the measured dynamic interfacial tension using subtractive clustering have been examined. Results state that the comparison of measured interfacial tension and predicted interfacial tension indicate acceptable accuracy of proposed model. Also more than 90 percent of data points have less than 3 percent absolute error.  相似文献   
28.
This paper presents influence analysis of bracket set on seismic performance of steel eave columns in Chinese traditional style buildings. Eight 1/1.5‐scale steel eave columns were constructed and tested under low cyclic reversed loading, including 4 specimens with bracket set and 4 specimens without bracket set. Based on the analysis of the strain of the specimens, the failure modes of the specimens were obtained. In addition, the hysteresis loops, skeleton curves, degradations of stiffness and strength, ductility, and dissipation capacities of the specimens were analyzed. Bracket set changed the force transfer mechanisms and failure modes of the specimens and had a significant influence on the seismic performance of the specimens. Compared with the specimens without bracket set, the yielded and ultimate bearing capacities of the specimens with bracket set improved by 30.7% and 24.0%, respectively. And also, the stiffness of the specimens with bracket set at the yielded and ultimate points increased by 52.8% and 135.6%. The dissipation capacities of the specimens with bracket set were 2.12 times those of the specimens without bracket set at yielded load. However, the ductility of the specimens with bracket set slightly decreased by 8.5%. It was shown that the seismic performance of the specimens with bracket set was better than that of the specimens without bracket set. The work in this paper provides a basis for further theoretical study on the seismic performance of steel eave columns in Chinese traditional style buildings.  相似文献   
29.
This article investigates an adaptive fuzzy tracking control problem for a class of nontriangular form systems with asymmetric time-varying full state constraints. Unknown functions are approximated by the fuzzy logic systems. A domination approach is employed to tackle the nontriangular form structure. Time-varying asymmetric barrier Lyapunov functions (ABLFs) are adopted to ensure full-state constraints satisfaction. Based on the backstepping technique and time-varying ABLFs, an adaptive controller is proposed and guarantees that all the signals in the closed-loop system are ultimately bounded and the time-varying full state constraints are met. Simulation examples are presented to further demonstrate the effectiveness of the proposed approach.  相似文献   
30.
何桥  许金 《中州煤炭》2020,(1):56-59
以煤矿安全隐患排查治理风险为研究对象,分析隐患排查闭环管理全过程,并基于此建立了隐患排查治理能力纵向评估指标体系,融合熵值法和集对分析理论,建立了煤矿安全隐患排查治理风险纵向评估模型,为企业更好地了解自身隐患排查治理能力及变化发展趋势提供参考,最后进行了实例分析。  相似文献   
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