基于信息融合的感应电动机定子故障检测方法研究

本文将信息融合的思想应用到感应电动机定子故障诊断中,将多种检测技术得到的信息进行综合,避免了依靠单一信号进行诊断的结果不可靠问题,提高了故障诊断的准确性。并通过对定子短路故障的实验研究,证实了该方法的可行性。     

斜拉桥190m主塔锚固区U形预应力管道摩阻试验研究

针对斜拉桥190m主塔塔身锚固区U形预应力管道摩阻试验的过程,没有像传统的斜拉桥做此试验时制作足尺模型,而是直接利用塔身位置上的设计孔道,采用2台千斤顶对拉进行摩阻试验,并对整个过程进行了总结,形成科研成果。该方法简单、方便,既节省了成本,又能达到试验目的,可供同类桥梁施工借鉴。     

斜拉桥110m高空现浇段施工创新研究

结合铁罗坪斜拉桥主梁现浇段的施工,介绍了其110m高空现浇段采用墩旁托架和钢铰线反支点预压施工新技术。该创新技术的采用,有效解决了施工支架和预压难题,同时了降低了施工成本。     

基于BP神经网络算法的特大跨度斜拉桥施工过程中的线形预测

随着斜拉桥跨度的增大,其几何非线性因素影响越来越明显,这就需要寻求考虑几何非线性影响的特大跨度斜拉桥施工线形预测方法。文章分析BP神经网络算法的基本原理及改进措施,借助Matlab语言建立预测模型,探讨其在特大跨度斜拉桥施工控制中的应用。以某主跨为1088m的特大跨度钢箱梁斜拉桥为工程背景,验证该方法的合理性和可行性,为同类型桥梁的线形控制提供参考。     

桩基主动托换技术进展

首先对桩基托换技术进行了简要的说明,然后综述了桩基主动托换技术取得的研究成果(包括理论研究、试验研究、模拟计算、施工工艺),最后分析了急需进一步研究的十个问题.     

用于模拟螺旋桨负载的双馈电机矢量控制研究

螺旋桨负载模拟是舰船电力推进系统中的重要研究内容.文中利用双馈电机四象限运行以及通过转子侧控制能降低变频器容量的特性,提出了双馈电机能量反馈系统模拟螺旋桨负载特性的方案.采用定子磁链定向的矢量控制策略,利用MATLAB/SIMULINK建立双馈电机模型和控制系统模型,实现不同工况下的稳态和动态特性模拟.仿真结果表明,转矩响应迅速、准确、稳定,采用矢量控制的双馈电机能量回馈系统具有良好的四象限负载特性模拟性能.     

FOLLICULO-STELLATE CELLS OFTHE RAT ANTERIOR PITUITARY RESPONDED TO ANGIOTENSIN Ⅱ BY INCREASING INTRACELLULAR CONCENTRATION

Objective The main purpose of this study was to investigate whether the folliculo-stellate cells (FSC) respond to angiotensin(Ang) Ⅱ by increasing intracellular free concentration ([]i) ,and where the o-rigin of mobilization is if that has occurred. Methods Pituitary cells in primary culture were prepared from male Wister rats(250g) by a conventional method and cultured in MEM supplemented with 4％ normal rat serum. Af-ter 2 days in culutre,cells were loaded with 1 μmol/L fura-PE3/AM for 1 h and subjected to a ment with Quanti Cell 700 system. Excitation wavelengths of 340 and 380 nm were selected by means of a computer-controlled filterwheel. Results The of FSC in the rat anterior pituitary was elevated by Ang Ⅱ. The eleva-tion of of FSC induced by 0. 1,1.0,10 and 100 nmol/L Ang Ⅱ was (56.33±6.18), (117.07± 36.07), (175.59 ± 40.01 ) and (216.02 ±11.52) nmol/L, respectively. The increase of of FSC induced by 100nmol/L Ang Ⅱ was not influenced by the medium without (0Ca),but significantly suppressed by thapsigargin (TG),an inhibitor of ATPase. The rate of responsive FSC to Ang Ⅱ (100 nmol/L) was 61.84％ which was obviously higher than that of pituitary endocrine cells (43.49％). Conclusion The present experiment demonstrates that the FSC in the rat anterior pituitary responds to Ang Ⅱ by increasing [which raises the possibility that Ang Ⅱ re-leased from either lactotrophs or gonadotrophs affects FSC through paracrine mechanism. The elevation of [induced by Ang Ⅱ presents a dosage-dependent relation, and is possibly because of the release of from an intra-cellular pool (s). Fashions of release are relative to the concentration of Ang Ⅱ. The results indicate that Ang Ⅱ functions as a paracrine factor among pituitary cells including FSC.     

鱼雷武器系统作战效能的分析体系研究

本文以作战效能为核心,以鱼雷武器系统为研究对象,构造了较为系统的鱼雷武器系统作战效能分析体系,讨论了相应的数学模型和分析方法,可以为武器系统的设计部门、使用部门和作战指挥、决策部门提供超前而可靠的决策预报,有助于选择方案,加快武器装备的研制.     

多轴汽车驻车制动性能分析方法

以三轴汽车为例,推导出多轴汽车的驻车极限坡度计算公式,并对其影响因素进行分析.在此基础上,提出了多轴汽车的驻车制动性能分析方法,即通过对驻车极限坡度与力矩法求出的最大驻车坡度进行比较而获得汽车的最大驻车坡度:外,提出了极限坡度利用率的概念,作为对驻车制动性能分析指标的补充.实例分析结果表明,该方法简单、实用,能对多轴汽车驻车制动性能进行有效分析.     

基于模态灵敏度分析的商用车驾驶室结构优化

建立某商用车驾驶室壳单元有限元模型,进行数值与实验模态计算及相关性分析。为提高驾驶室整体1阶扭转频率,结合门框区域的梁单元模型,建立驾驶室梁壳混合有限元模型;进行基于梁截面力学特性的模态灵敏度分析,获得灵敏梁单元组件,进而找出壳单元有限元模型的对应灵敏区域,对其进行形貌优化,借以指导构件截面尺寸优化,获得结构最优方案,该方案提高了驾驶室的1阶扭转频率。对比分析表明,优化结果及优化分析方法合理有效。