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Search Results: 1 - 10 of 24826 matches for " 靳静 "
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预制装配式220 kV终端变电站典型设计研究
Study on Typical Design of Fabricated 220 kV Terminal Substation
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Journal of Electrical Engineering (JEE) , 2016, DOI: 10.12677/JEE.2016.43017
Abstract:
随着电网建设进度的加快,如何缩短变电站的建设周期显得日益重要。预制装配式变电站通过工厂预制和现场安装两个阶段建设,越来越成为城市变电站推崇的建设方式。另外,以往必须先确定设备再进行设计,从而再进行施工安装的流程成为了必须打破的瓶颈。本设计方案主要研究预制装配式变电站内的主要设备的通用基础,可在设备订货前就按通用基础、通用接口予以设计,实现土建先行,从而达到加快工程建设速度的目的。
With the accelerated construction schedule of power grid, how to cut construction period of substation is an increasingly important issue. Through the two stages of construction of factory prefabrication and site installation, fabricated substation is becoming more and more respected city substation construction side. Moreover, we must design after determining devices firstly, and then is civil work and equipment installation. Now we must break the bottleneck of this traditional mode. The main research of this design scheme is the general base of electrical equipments in fabricated substation. In accordance with the general base and general interface, we can design before equipment ordering and realize civil work first, so as to achieve the purpose of speeding up the pace of substation construction.
压电压磁双层材料界面裂纹断裂特性进一步分析
,马鹏
工程力学 , 2013, DOI: 1000-4750(2013)06-0327-07
Abstract: 该文利用积分变换和奇异积分方程技术研究压电压磁双材料界面裂纹在磁导、电位移和机械载荷作用下的二维断裂问题。本文仅考虑四种理想的裂纹面电磁边界条件即磁电不导通(情形1)、磁导通电不导通(情形2)、磁不导通电导通(情形3)和磁电导通(情形4)。导出了应力强度因子(SIF)和能量释放率(ERR)的表达式,给出了ERR的大量数值结果,并与已有结果进行了对比。研究成果对压电压磁多层复合结构的设计具有理论与应用价值。
磁电弹圆柱中轴对称压缩波的传播
,梁小勇?
河北科技大学学报 , 2011, DOI: 10.7535/hbkd.2011yx06006
Abstract: 为研究无限长横观各向同性磁电弹圆柱中轴向对称压缩波的传播,考虑16种边界条件,得出广义频散方程,并讨论不同边界条件下波的频散特性。数值结果表明边界条件对磁电弹圆柱中轴向对称压缩波的传播特性有着显著的影响。
压电压磁双层材料界面二维裂纹分析
马鹏,冯文杰,
工程力学 , 2011,
Abstract: 该文利用积分变换和奇异积分方程技术研究压电压磁双材料界面裂纹二维断裂问题。假设界面上压电材料电势和压磁材料磁势为零;压电层表面受机械载荷和电位移作用,压磁层表面受机械载荷和磁导作用。导出了相应问题的应力强度因子和机械能量释放率的表达式,给出了机械能量释放率的数值结果。结果表明:在同样机械载荷作用下,压电压磁双材料界面裂纹要比相应的弹性双材料不易产生和(或)传播,而且增加层的高度可以抑制裂纹扩展。研究结果对多层电磁复合结构的设计具有理论与应用价值。
浆砌石重力坝加高中弹性模量对坝体的影响
,建伟,梁童
人民黄河 , 2009,
Abstract: ?通过对宝泉电站下水库大坝进行二维有限元分析,研究了浆砌石重力坝加高过程中,新、老坝体弹性模量的差异性对坝体位移及坝体受力的影响,结果表明:当新、老坝体材料弹性模量在一定允许范围内变化时,随着坝体弹性模量的增加,坝体的整体刚度增加,总位移随之减小;坝体内部垂向正应力对新、老坝体弹性模量变化不敏感,坝踵、坝趾垂向正应力对新、老坝体弹性模量变化敏感.
复杂坝基浆砌石重力坝稳定分析
罗全胜,,建伟
人民黄河 , 2009,
Abstract: ?以宝泉电站下水库大坝特殊坝段为例,采用刚体极限平衡法时复杂坝基浆砌石重力坝的抗滑稳定性进行了分析,由其二维有限元计算结果可知,校核水位时为最危险工况,坝体与坝基接触面上的最大垂向正应力和最大切向剪应力均出现在坝趾处.介绍了特殊坝段的极限抗倾稳定验算方法,指出在施工过程中确保坝体与基础充分结合是特殊坝段抗滑稳定的前提条件.
基于免疫自整定的自抗扰控制研究
,李大字,其兵
- , 2016, DOI: 10.13543/j.bhxbzr.2016.02.018
Abstract: 结合自抗扰(ADRC)和生物免疫的控制思想设计了免疫 ADRC 控制器。设计的免疫 ADRC 控制器保留了传统 ADRC 控制器的结构,并运用生物免疫机制实现了自抗扰控制器中非线性状态误差反馈(NLSEF)的参数自整定。这样设计的控制器可以提高传统控制系统的抗干扰能力,优化了控制器性能。设计的免疫 ADRC 算法可适用于 N 阶对象,仿真部分以二阶运动模型为例。 仿真实验表明,免疫 ADRC 既可以保存传统 ADRC 快速跟踪和有效观测的优点,又能在此基础上增强系统的抗扰能力,提高了系统的稳定性。
Abstract: A controller combining the idea of an immune controller (IC) and an active disturbance rejection controller (ADRC) has been designed and is denoted as an immune ADRC. Parameters for self-tuning of the nonlinear state error feedback (NLSEF) can be implemented using the designed Immune ADRC controller, in which all the parts of traditional ADRC controller are retained. In this way, the designed controller can improve the disturbance rejection capability of the control system, as well as optimize the performance of the controller. The immune ADRC algorithm can be also be applied to higher order systems. A second order motion model was used in simulations.The simulation results demonstrate that the immune ADRC not only retains the advantages of a traditional ADRC,such as fast-tracking and available observation, but also offers better performances in terms of disturbance rejection and improves the stability of the system.
HRV在管制员疲劳检测中的适用性
Application of HRV in air traffic controllers' fatigue detection

慧斌,,吕川
- , 2018, DOI: 10.13700/j.bh.1001-5965.2018.0122
Abstract: 摘要 为研究心率变异性(HRV)指标在管制员(ATC)疲劳检测中的适用性,搭建模拟管制实验平台,利用生理记录仪实时记录20名被试正常和疲劳状态下的心电(ECG)信号,并采集其主观疲劳度(卡罗林斯卡嗜睡量表)和操作绩效。利用偏相关分析选取与被试疲劳等级相关性高的心率变异性指标,并用于管制员疲劳检测的多元线性回归建模。分析结果表明:SDNN与被试的疲劳状态无相关性;LFnorm和HFnorm与疲劳程度呈弱相关;RR间期均值、LF/HF均与被试的疲劳度存在较强的相关性,二者结合建立的多元线性回归模型,拟合优度大于0.5,RR间期均值和LF/HF可作为检测管制员疲劳的有效指标。本文研究成果可为未来的管制员疲劳实时检测提供科学依据和实验支撑。
Abstract:In order to study the application of heart rate variability (HRV) indexes in the fatigue detection of the air traffic controllers (ATC), the simulation control experiment platform was set up, the real-time physiological recorder was used to record the electrocardiogram (ECG) signals of 20 subjects in real time under normal and fatigue conditions, and their subjective fatigue (Karolinsaka sleepingness scale) and operational performance were collected. The HRV index with high correlation with fatigue grade was selected by partial correlation analysis and used to model the multivariate linear regression model for fatigue detection. The analysis results show that there is no correlation between the SDNN and the fatigue status of the subjects; LFnorm and HFnorm are weakly correlated with the fatigue; RR interval and LF/HF have a strong correlation with the fatigue degree of the controlled subjects; The multivariate linear regression model, the goodness of fit is greater than 0.5, RR interval and LF/HF can be used as valid indicators of controller fatigue detection. This study can provide scientific evidence and experimental support for the future real-time detection of controller fatigue.
利用HARQ多用户MIMO系统的自适应反馈方法
,李立华,,张平,刘泽民
北京邮电大学学报 , 2010, DOI: 10.13190/jbupt.201001.111.ranj
Abstract:
碳一化工路线制备乙二醇研究进展
宋河远,荣华,康美荣,
催化学报 , 2013, DOI: 10.1016/S1872-2067(12)60529-4
Abstract: ?乙二醇(EG)是一种重要的化工原料,主要用来生产新型聚酯纤维.近年来由于我国聚酯产业发展迅速,极大的推动了对乙二醇的需求.碳一化工路线以资源丰富、价格便宜的天然气或煤为原料合成乙二醇,有着诱人的工业化前景.综述了以合成气为原料合成乙二醇的研究进展,包括合成气直接合成法、甲醛羰化法、CO偶联法、甲醛氢甲酰化法以及甲醛缩合法等.
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