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Utility of fluid inclusion paleo-temperature in petroleum system modelling:A case study from western offshore,India
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作者 V.Nandakumar S.Shivapriya Silpa Thankan 《Energy Geoscience》 EI 2024年第2期101-119,共19页
The paleo-temperature(Th)data from fluid inclusions are utilized for thermal history modelling using PetroMod software.Generally,bottom hole temperature(BHT)and vitrinite reflectance(Ro)measurements are widely used in... The paleo-temperature(Th)data from fluid inclusions are utilized for thermal history modelling using PetroMod software.Generally,bottom hole temperature(BHT)and vitrinite reflectance(Ro)measurements are widely used in petroleum system modelling(PSM)in the oil industry for calibration purposes.Th representing the minimum temperature of fluid entrapment estimated from fluid-inclusion study provides extra support to build the thermal models for PSM.Fluid inclusion parameters along with Rock-Eval pyrolysis analysis have been used to predict the maturity of oil in terms of API gravity as well as the maturity of source rocks respectively.Two exploratory wells RV-1(Mumbai Offshore Basin)and KK4C-A-1(Kerala-Konkan Offshore Basin),India were examined and the T_(h)from most of the fluid inclusions of wells RV-1 and KK4C-A-1 fell in the oil window range of 60-140℃suggesting thermal conditions favourable for oil generation in both of the wells.T_(h)of coeval aqueous inclusions along with the Hydrocarbon Fluid inclusions(HCFIs)was used to calibrate PSM.Vital parameters show that source rocks of well RV-1 are mature and that of well KK4C-A-1 are immature.Two sets of PSM are created in terms of generation and expulsion for the dry wells RV-1 and KK4C-A-1 and calibrated each well using fluid inclusion Th and BHT.From the fluid inclusion analysis method,it is evident that hydrocarbon generation happened in both wells and the paleo-temperature indicates that the formations of both wells were subjected to temperatures in the oil window range,even though it was designated as dry wells in the present scenario.The present study highlights the application of fluid inclusion paleo-temperature(Th)during calibration instead of commonly used methods.We could obtain desirable and accurate data output from PSM using T_(h) calibration. 展开更多
关键词 Paleo-temperature(T_(h)) hydrocarbon fluid inclusion Petroleum system modelling Petroleum generation and expulsion Western offshore basin
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骨科术后患者万古霉素AUC_(0~24h)影响因素分析及预测模型研究
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作者 杨浩 熊雄 +1 位作者 刘长江 金小越 《中国药师》 CAS 2024年第1期66-75,共10页
目的探讨万古霉素在骨科术后患者中的24 h曲线下面积(AUC_(0~24h))的影响因素,并预测分析AUC_(0~24h)较好的药代动力学模型。方法纳入新疆医科大学第六附属医院2018年1月至2022年12月进行骨科手术并使用万古霉素的患者,收集患者的基本... 目的探讨万古霉素在骨科术后患者中的24 h曲线下面积(AUC_(0~24h))的影响因素,并预测分析AUC_(0~24h)较好的药代动力学模型。方法纳入新疆医科大学第六附属医院2018年1月至2022年12月进行骨科手术并使用万古霉素的患者,收集患者的基本信息、用药情况、血常规和血生化指标,分析影响骨科术后患者万古霉素AUC_(0~24h)的因素。采用一级药代动力学公式、个体化给药辅助决策系统(JPKD)和万古霉素日剂量消除率公式计算AUC_(0~24h)。结果最终纳入91例患者,结果发现胱抑素C(OR=189.168,P=0.005)和单次剂量(OR=19.160,P<0.001)是骨科术后患者万古霉素AUC_(0~24h)的独立保护因素,视黄醇结合蛋白是万古霉素AUC_(0~24h)的独立危险因素(OR=0.910,P<0.05)。通过对骨科术后患者万古霉素AUC_(0~24h)模型预测分析,JPKD软件和万古霉素日剂量消除率公式的绝对权重偏差均低于30%,JPKD软件和万古霉素日剂量消除率公式的AUC_(0~24h)与一级药代动力学公式的AUC_(0~24h)组内相关系数分别为0.781和0.524。结论胱抑素C是影响骨科术后患者万古霉素AUC_(0~24h)的重要因素,JPKD软件较万古霉素日剂量消除率公式方法更适用于预测骨科术后万古霉素AUC_(0~24h)。 展开更多
关键词 骨科术后 万古霉素 24 h曲线下面积 预测模型
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基于自抗扰控制的H桥逆变器的混沌研究
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作者 马幼捷 何晓宇 +1 位作者 周雪松 张超 《电气传动》 2024年第7期11-15,21,共6页
为了解决新能源发电系统逆变器出现混沌的问题,提出了一种基于自抗扰控制的H桥逆变器的调节方案。针对处于混沌状态的逆变器的稳态和动态特性差的现象,构建了逆变器的离散模型,并通过建立跟踪微分器、扩张状态观测器以及状态误差反馈控... 为了解决新能源发电系统逆变器出现混沌的问题,提出了一种基于自抗扰控制的H桥逆变器的调节方案。针对处于混沌状态的逆变器的稳态和动态特性差的现象,构建了逆变器的离散模型,并通过建立跟踪微分器、扩张状态观测器以及状态误差反馈控制律进行混沌控制。通过分岔图、折叠图以及仿真分析,结果可知基于自抗扰控制的H桥逆变器比基于比例控制的H桥逆变器的稳定范围扩大了45%,有效地抑制了混沌现象的发生。通过分析可得出:该控制策略对系统的混沌行为能够进行抑制,拓宽了系统稳定工作范围。 展开更多
关键词 自抗扰控制 h桥逆变器 离散模型 混沌 分岔图
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锂电池自适应无迹H∞滤波SOC估计研究
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作者 钱伟 赵大中 +2 位作者 郭向伟 王亚丰 李文静 《储能科学与技术》 CAS CSCD 北大核心 2024年第11期4078-4088,共11页
荷电状态(state of charge,SOC)作为表征锂电池剩余电量的关键指标,其精确估计对于合理使用电池电量、保障电池安全具有重要意义。本文针对基于H∞滤波(H infinity filter,HIF)估计SOC时鲁棒性好但估计精度低的问题,提出一种自适应无迹... 荷电状态(state of charge,SOC)作为表征锂电池剩余电量的关键指标,其精确估计对于合理使用电池电量、保障电池安全具有重要意义。本文针对基于H∞滤波(H infinity filter,HIF)估计SOC时鲁棒性好但估计精度低的问题,提出一种自适应无迹H∞滤波(adaptive unscented H infinity filter,AU_HIF)SOC估计方法,以提高SOC估计精度。首先,选择能够在精度和复杂度间取得良好平衡的双极化(dual polarization,DP)等效电路模型进行新型估计算法的设计;其次,结合无迹卡尔曼滤波(unscented Kalman filter,UKF)算法相比于传统扩展卡尔曼滤波(extended Kalman filter,EKF)算法更适用于非线性系统状态估计的特点,文章基于先验误差协方差矩阵设计新型渐消因子,实现自适应无迹H∞滤波算法的设计,以减小陈旧测量值对估计结果的影响,提高滤波算法的跟踪能力及估计精度。最后,通过搭建自主实验平台获取实际模拟工况数据,验证了文章所提自适应无迹H∞滤波算法相比于传统H∞滤波算法、传统UKF算法和其他类型改进H∞滤波算法具有更高的估计精度及更好的鲁棒性。文章研究内容对提高新能源汽车、储能电站等电池系统的SOC估计精度具有重要意义。 展开更多
关键词 锂电池 SOC h∞滤波 DP模型 渐消因子
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曲面滑坡条件下h型抗滑桩受力性状模型试验研究
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作者 李永辉 张信 +1 位作者 张鼎浩 王卫中 《工程力学》 EI CSCD 北大核心 2024年第7期134-146,共13页
依托公路大型滑坡治理工程,设计物理模型试验装置,设置同一滑面和桩体锚固深度,进行6组h型抗滑桩室内模型试验,分析不同连梁长度及后排桩悬臂段高度(连梁高度)时桩顶位移变化规律、桩身弯矩和桩后土压力分布特征,研究曲面滑坡条件下h型... 依托公路大型滑坡治理工程,设计物理模型试验装置,设置同一滑面和桩体锚固深度,进行6组h型抗滑桩室内模型试验,分析不同连梁长度及后排桩悬臂段高度(连梁高度)时桩顶位移变化规律、桩身弯矩和桩后土压力分布特征,研究曲面滑坡条件下h型抗滑桩受力性状及其内在机制,并给出桩后滑坡推力抛物线型分布的一般函数表达式。试验结果表明:h型抗滑桩受力过程桩顶水平位移变化表现出较为明显的三阶段特征,桩身弯矩分布呈现正、负交变现象,后排桩桩顶水平位移及桩身弯矩明显大于前排桩;降低后排桩悬臂段高度不影响桩身弯矩分布特征,但对于桩顶水平位移及桩身弯矩量值,后排桩明显减小,前排桩有所增大;增减连梁长度对前、后排桩之间荷载传递与协同受力特性影响显著,使得前、后排桩水平变形及桩身弯矩随之产生变化;连梁正、负弯矩极值均处于连梁端部,相比于连梁长度,连梁弯矩的大小及分布形态受后排桩悬臂段长度的影响更为明显;随着连梁长度的减小或后排桩悬臂段长度的增加,后排桩桩后土压力表现出抛物线型、重心偏下的抛物线型及近似梯形的分布形态。此外,给出的滑坡推力函数表达式能较好的表征其抛物线型分布特征,通过调整合力作用点参数,亦可对滑坡推力近似梯形的分布类型进行描述。 展开更多
关键词 公路边坡 h型抗滑桩 模型试验 受力性状 土压力分布
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H形钢构件双向压弯下全过程弯矩计算模型
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作者 程欣 杜辉波 +1 位作者 王彤彤 陈以一 《工程力学》 EI CSCD 北大核心 2024年第8期107-119,共13页
为探究可发展全截面塑性的H形钢构件在双向压弯加载全过程中塑性应力及两主轴弯矩的发展机制,基于经由已有实验数据校核过的建模方法,采用ABAQUS建立了不同轴压比、腹板和翼缘宽厚比的H形截面构件在不同加载角度下的参数分析模型。结合... 为探究可发展全截面塑性的H形钢构件在双向压弯加载全过程中塑性应力及两主轴弯矩的发展机制,基于经由已有实验数据校核过的建模方法,采用ABAQUS建立了不同轴压比、腹板和翼缘宽厚比的H形截面构件在不同加载角度下的参数分析模型。结合有限元分析结果,考察了双向压弯下H形截面钢构件的塑性应力发展规律,引入平截面假定,对其应力分布形式进行一定的简化处理。进一步,通过最小二乘法拟合得到相关参数,建立加载位移、塑性发展程度和宏观承载能力三者之间内在联系,构建H形钢构件双向弯矩的理论计算模型。该模型充分考虑了截面尺寸、位移加载方向角、轴压比和加载位移的影响。通过对模型计算结果的分析,验证了该模型可得到构件在加载任意时刻的应力分布形式,并为考虑一定截面塑性发展的双向抗弯设计提供更为简便的设计方法。 展开更多
关键词 应力模型 全塑性截面 h形截面 双向压弯 截面中性轴
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基于最小二乘法和BP神经网络的磁流变阻尼器H-B模型参数辨识方法
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作者 张忠奎 张晗 闫洋洋 《机床与液压》 北大核心 2024年第4期126-131,共6页
针对Bingham模型磁流变阻尼器由于剪切稀化效应带来的阻尼力计算误差,在理论和仿真分析的基础上,提出一种最小二乘法和BP神经网络相结合的方法,对磁流变阻尼器H-B模型进行参数辨识,获得各参数与电流的关系,从而对磁流变阻尼器的阻尼力... 针对Bingham模型磁流变阻尼器由于剪切稀化效应带来的阻尼力计算误差,在理论和仿真分析的基础上,提出一种最小二乘法和BP神经网络相结合的方法,对磁流变阻尼器H-B模型进行参数辨识,获得各参数与电流的关系,从而对磁流变阻尼器的阻尼力进行准确计算。最后通过磁流变阻尼器实验对理论方法进行验证。结果表明:借助于磁流变阻尼器的仿真分析,最小二乘法和BP神经网络相结合的磁流变阻尼器H-B模型参数辨识方法精确度高、吻合性好,验证了参数辨识结果的通用性及准确性。 展开更多
关键词 磁流变液阻尼器 h-B模型 最小二乘法 BP神经网络
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基于混沌的H桥逆变器的非奇异终端滑膜控制
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作者 马幼捷 何晓宇 周雪松 《天津理工大学学报》 2024年第5期62-68,共7页
针对逆变器的分岔和混沌现象,建立逆变器的离散模型,通过分岔图、Lyapunov指数和折叠图分析非线性行为,并计算出系统的稳定运行范围及混沌运行范围。文中提出一种非奇异终端滑膜控制策略,设计切换面函数,推导逆变器的反馈控制律。最后... 针对逆变器的分岔和混沌现象,建立逆变器的离散模型,通过分岔图、Lyapunov指数和折叠图分析非线性行为,并计算出系统的稳定运行范围及混沌运行范围。文中提出一种非奇异终端滑膜控制策略,设计切换面函数,推导逆变器的反馈控制律。最后进行仿真,仿真结果表明:非奇异滑膜控制能够有效抑制系统的混沌行为,从而拓宽了系统稳定工作范围,相比于比例积分控制(proportional integral derivative,PI),稳定范围扩大了80%。由此可以使得逆变器实现稳定工作,有很强的实际应用价值。 展开更多
关键词 非奇异 终端滑膜控制 h桥逆变器 离散模型 混沌
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He-Hutchinson模型在连续陶瓷纤维增韧陶瓷基复合材料研究中的应用 被引量:1
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作者 马昕 刘海韬 +1 位作者 姜如 孙逊 《材料导报》 EI CAS CSCD 北大核心 2024年第3期90-96,共7页
基于裂纹扩展的能量释放率准则,He-Hutchinson(H-H)模型可以预判连续陶瓷纤维增韧陶瓷基复合材料(CMCs)的基体裂纹在界面处的传播路径,对CMCs的增韧设计有着重要的指导价值,但目前尚未见H-H模型在CMCs研究领域的系统性综述文献。本文首... 基于裂纹扩展的能量释放率准则,He-Hutchinson(H-H)模型可以预判连续陶瓷纤维增韧陶瓷基复合材料(CMCs)的基体裂纹在界面处的传播路径,对CMCs的增韧设计有着重要的指导价值,但目前尚未见H-H模型在CMCs研究领域的系统性综述文献。本文首先介绍了H-H模型的力学基础以及应用于CMCs中的必要简化过程,得出基于材料组元断裂能和弹性失配系数的裂纹偏转判据。基于目前形成的材料微观力学参数测量方法,结合CMCs脆性、微观结构复杂的特点,系统总结归纳了适用于CMCs的原位弹性模量、材料断裂能以及界面脱粘能的测量方法及优缺点。基于原位微观力学参数,重点综述与讨论了H-H模型在多孔基体CMCs和含界面相CMCs中的应用进展,最后指出了H-H模型目前存在的主要问题,并对其后续发展提出了建议。 展开更多
关键词 h-h模型 陶瓷基复合材料 微观力学 裂纹偏转
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Numerical modeling of SiC by low-pressure chemical vapor deposition from methyltrichlorosilane 被引量:6
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作者 Kang Guan Yong Gao +5 位作者 Qingfeng Zeng Xingang Luan Yi Zhang Laifei Cheng Jianqing Wu Zhenya Lu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第6期1733-1743,共11页
The development of functional relationships between the observed deposition rate and the experimental conditions is an important step toward understanding and optimizing low-pressure chemical vapor deposition(LPCVD)or... The development of functional relationships between the observed deposition rate and the experimental conditions is an important step toward understanding and optimizing low-pressure chemical vapor deposition(LPCVD)or low-pressure chemical vapor infiltration(LPCVI).In the field of ceramic matrix composites(CMCs),methyltrichlorosilane(CH3 SiCl3,MTS)is the most widely used source gas system for SiC,because stoichiometric SiC deposit can be facilitated at 900°C–1300°C.However,the reliability and accuracy of existing numerical models for these processing conditions are rarely reported.In this study,a comprehensive transport model was coupled with gas-phase and surface kinetics.The resulting gas-phase kinetics was confirmed via the measured concentration of gaseous species.The relationship between deposition rate and 24 gaseous species has been effectively evaluated by combining the special superiority of the novel extreme machine learning method and the conventional sticking coefficient method.Surface kinetics were then proposed and shown to reproduce the experimental results.The proposed simulation strategy can be used for different material systems. 展开更多
关键词 Chemical vapor deposition MTS/h2 Gas-phase and surface kinetics Extreme learning machine method Numerical model
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基于D-H参数的磁阻式球形电机动力学建模
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作者 李瑞英 李国丽 +1 位作者 鞠鲁峰 王群京 《电气工程学报》 CSCD 北大核心 2024年第1期150-158,共9页
三自由度球形电机的动力学模型是对转子运动过程的数学描述,在球形电机的闭环控制中用于计算转子从当前位置运动到期望位置时所需要的驱动转矩。以计算磁阻式球形电机驱动转矩为目标,提出一种动力学方程的建模方法。针对磁阻式球形电机... 三自由度球形电机的动力学模型是对转子运动过程的数学描述,在球形电机的闭环控制中用于计算转子从当前位置运动到期望位置时所需要的驱动转矩。以计算磁阻式球形电机驱动转矩为目标,提出一种动力学方程的建模方法。针对磁阻式球形电机的运动特征,将球形转子等效为三个串联旋转关节,推导出磁阻式球形电机基于D-H参数的动力学方程,再对方程中的未知参数进行辨识,最终模型的预测结果与仿真结果有较高的拟合度,试验验证了该模型在设定运动工况下的可靠性,为磁阻式球形电机驱动控制提供了理论基础。 展开更多
关键词 磁阻式球形电机 D-h参数 动力学模型 机器人 参数辨识
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Solubility measurement and thermodynamic modeling of carbamazepine(form III)in five pure solvents at various temperatures 被引量:1
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作者 Wenju Liu Zehua Bao +3 位作者 Yanmin Shen Tiantian Yao Hongjuan Bai Xinyu Jin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第5期231-235,共5页
In this work,the solubilities of carbamazepine(CBZ)(form III)in ethyl acetate,methyl acetate,ethylene glycol,chloroform and cyclohexylamine were determined by laser monitoring techniques at pressure above sea level,an... In this work,the solubilities of carbamazepine(CBZ)(form III)in ethyl acetate,methyl acetate,ethylene glycol,chloroform and cyclohexylamine were determined by laser monitoring techniques at pressure above sea level,and the solubility data of CBZ(form III)in different pure solvents were fitted by the Modified Apelblat model andλh model.The result shows that the solubility of CBZ(form III)in five solvents increases as temperature rises,and the solubility in chloroform was the largest.The experimental solubility values of CBZ(form III)in ethyl acetate,methyl acetate,chloroform and cyclohexylamine were in better agreement with the simulated fitting values of theλh model.For ethylene glycol,the r value was much larger than the other four solvents,and it can be seen from theλh model that ethylene glycol was closer to the ideal solution system than the other four solvents. 展开更多
关键词 SOLUBILITY CARBAMAZEPINE (form III) Modified Apelblat model λh model
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一种基于Si/SiC级联H桥逆变器的高性能模型预测控制方法
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作者 郭子跃 全惠敏 +1 位作者 彭子舜 戴瑜兴 《电子学报》 EI CAS CSCD 北大核心 2024年第9期3000-3009,共10页
Si/SiC级联H桥逆变器,能够利用不同器件的开关组合保证低输出电流谐波畸变率(Total Harmonic Distortion,THD)和装置效率,但也带来了Si/SiC子模块开关分配的难题.对此,本论文设计一种变权重的模型预测控制方法(Model Predictive Control... Si/SiC级联H桥逆变器,能够利用不同器件的开关组合保证低输出电流谐波畸变率(Total Harmonic Distortion,THD)和装置效率,但也带来了Si/SiC子模块开关分配的难题.对此,本论文设计一种变权重的模型预测控制方法(Model Predictive Control,MPC)选择总开关状态并分配子模块开关组合.该方法在选取逆变器总开关状态和Si/SiC子模块开关组合的代价函数中引入基于器件开关损耗的变权重,以改善逆变器的效率和输出电流谐波畸变率.在五电平Si/SiC级联H桥逆变装置上验证了变权重MPC的有效性,相比于固定权重MPC,输出电流THD最多降低2.05%,装置损耗最多降低4.53%. 展开更多
关键词 碳化硅MOSFET 硅IGBT 级联h桥逆变器 开关损耗 模型预测控制
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双向加载下不同因素对H型钢构件板壳节段损伤域长度的影响
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作者 田钦 刘康 康彩霞 《南昌大学学报(工科版)》 CAS 2024年第1期37-44,共8页
为研究双向加载条件下,轴压比、长细比、腹板高厚和翼缘宽厚比4个主要参数对H型钢构件损伤域长度的影响,利用有限元软件ABAQUS建立板壳模型进行有限元分析,并给出了双向加载下板壳节段损伤域长度的计算公式。分析结果表明:双向加载更加... 为研究双向加载条件下,轴压比、长细比、腹板高厚和翼缘宽厚比4个主要参数对H型钢构件损伤域长度的影响,利用有限元软件ABAQUS建立板壳模型进行有限元分析,并给出了双向加载下板壳节段损伤域长度的计算公式。分析结果表明:双向加载更加符合实际情况,所得损伤域长度偏大,提高了板壳节段取值的准确性;在一定区域内,损伤域长度与轴压比和腹板高厚比呈正相关,且增长幅度可达初始值的1倍以上,与翼缘宽厚比呈负相关,最大降幅可达50%以上。当长细比小于临界值时,两者呈负相关,最大降幅达34.28%;反之,两者呈正相关,最大增幅达58.26%。 展开更多
关键词 h型钢构件 多尺度模型 双向加载 影响参数 损伤域长度
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Species distribution modeling in regions of high need and limited data: waterfowl of China 被引量:1
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作者 Diann J.Prosser Changqing Ding +3 位作者 R.Michael Erwin Taej Mundkur Jeffery D.Sullivan Erle C.Ellis 《Avian Research》 CSCD 2018年第1期49-62,共14页
Background: A number of conservation and societal issues require understanding how species are distributed on the landscape, yet ecologists are often faced with a lack of data to develop models at the resolution and e... Background: A number of conservation and societal issues require understanding how species are distributed on the landscape, yet ecologists are often faced with a lack of data to develop models at the resolution and extent desired, resulting in inefficient use of conservation resources.Such a situation presented itself in our attempt to develop waterfowl distribution models as part of a multi-disciplinary team targeting the control of the highly pathogenic H5N1 avian influenza virus in China.Methods: Faced with limited data, we built species distribution models using a habitat suitability approach for China's breeding and non-breeding(hereafter, wintering) waterfowl.An extensive review of the literature was used to determine model parameters for habitat modeling.Habitat relationships were implemented in GIS using land cover covariates.Wintering models were validated using waterfowl census data, while breeding models, though developed for many species, were only validated for the one species with sufficient telemetry data available.Results: We developed suitability models for 42 waterfowl species(30 breeding and 39 wintering) at 1 km resolution for the extent of China, along with cumulative and genus level species richness maps.Breeding season models showed highest waterfowl suitability in wetlands of the high-elevation west-central plateau and northeastern China.Wintering waterfowl suitability was highest in the lowland regions of southeastern China.Validation measures indicated strong performance in predicting species presence.Comparing our model outputs to China's protected areas indicated that breeding habitat was generally better covered than wintering habitat, and identified locations for which additional research and protection should be prioritized.Conclusions: These suitability models are the first available for many of China's waterfowl species, and have direct utility to conservation and habitat planning and prioritizing management of critically important areas, providing an example of how this approach may aid others faced with the challenge of addressing conservation issues with little data to inform decision making. 展开更多
关键词 ANATIDAE Avian influenza China habitat suitability h5N1 Spatial analysis Species distribution models WATERFOWL
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Modeling and Design of H-Infinity Controller for Piezoelectric Actuator LIPCA 被引量:2
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作者 Gigun Lee Kwanwoo You +3 位作者 Taesam Kang Kwang Joon Yoon Jeong Oog Lee Jung Keun Park 《Journal of Bionic Engineering》 SCIE EI CSCD 2010年第2期168-174,共7页
We proposed a dynamic model identification and design of an H-Infinity (i.e.H) controller using a LightweightPiezo-Composite Actuator (LIPCA).A second-order dynamic model was obtained by using input and output dat... We proposed a dynamic model identification and design of an H-Infinity (i.e.H) controller using a LightweightPiezo-Composite Actuator (LIPCA).A second-order dynamic model was obtained by using input and output data, and applyingan identification algorithm.The identified model coincides well with the real LIPCA.To reduce the resonating mode that istypical of piezoelectric actuators, a notch filter was used.A feedback controller using the Hcontrol scheme was designed basedon the identified dynamic model; thus, the LIPCA can be easily used as an actuator for biomemetic applications such as artificialmuscles or macro/micro positioning in bioengineering.The control algorithm was implemented using a microprocessor, analogfilters, and power amplifying drivers.Our simulation and experimental results demonstrate that the proposed control algorithmworks well in real environment, providing robust performance and stability with uncertain disturbances. 展开更多
关键词 piezoelectric actuator model identification h-infinity controller biomimetic artificial muscle LIPCA
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Measurement and Modeling for the Solubility of Hydrogen Sulfide in Primene JM-T
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作者 李杰 林晓 +3 位作者 宁朋歌 曹宏斌 张懿 John C. Crittenden 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第1期89-97,共9页
The primary aliphatic amine Primene JM-T was investigated as a potential absorbent for H2S removal. The solubility of HzS in JM-T was measured at 298, 313,333,353, and 368 K with H2S partial pressures from 20 to 760 k... The primary aliphatic amine Primene JM-T was investigated as a potential absorbent for H2S removal. The solubility of HzS in JM-T was measured at 298, 313,333,353, and 368 K with H2S partial pressures from 20 to 760 kPa and HzS loading from 0.02 to 0.8 mol H2S per mol JM-T. Relevant physical properties, such as density, viscoslty and dielectric constant, ot the matenal were measured. 'The thermodynamlc model with two-suttlX Margules equation was used to correlate the experimental vapor-liquid equilibrium data. Furthermore, the absorption mechanism in non-aqueous system is suggested and the difference between non-aqueous and aqueous absorption system is pointed out. 展开更多
关键词 Primene JM-T h2S removal ABSORPTION thermodynamic model
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Solubility and mass transfer of H2, CH4, and their mixtures in vacuum gas oil: An experimental and modeling study
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作者 Zhigang Lei Yifan Jiang +4 位作者 Yao Liu Yichun Dong Gangqiang Yu Yanyong Sun Ruili Guo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第12期3000-3009,共10页
In this work,the solubility data and liquid-phase mass transfer coefficients of hydrogen(H2),methane(CH4)and their mixtures in vacuum gas oil(VGO)at temperatures(353.15-453.15 K)and pressures(1-7 MPa)were measured,whi... In this work,the solubility data and liquid-phase mass transfer coefficients of hydrogen(H2),methane(CH4)and their mixtures in vacuum gas oil(VGO)at temperatures(353.15-453.15 K)and pressures(1-7 MPa)were measured,which are necessary for catalytic cracking process simulation and design.The solubility of H2 and CH4 in VGO increases with the increase of pressure,but decreases with the increase of temperature.Henry’s constants of H2 and CH4 follow the relation of In H=-413.05/T+5.27 and In H=-990.67/T+5.87,respectively.The molar fractions of H2 and system pressures at different equilibrium time were measured to estimate the liquid-phase mass transfer coefficients.The results showed that with the increase of pressure,the liquid-phase mass transfer coefficients increase.Furthermore,the solubility of H2 and CH4 in VGO was predicted by the predictive COSMO-RS model,and the predicted values agree well with experimental data.In addition,the gas-liquid equilibrium(GLE)for H2+CH4+VGO system at different feeding gas ratios in volume fraction(i.e.,H285%+CH415%and H290%+CH410%)was measured.The selectivity of H2 to CH4 predicted by the COSMO-RS model agrees well with experimental data.This work provides the basic thermodynamic and dynamic data for fuel oil catalytic cracking processes. 展开更多
关键词 h2 Ch4 VACUUM gas oil(VGO) SOLUBILITY Mass transfer COSMO-RS model
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火星沉降H-ENA的分布与特性
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作者 张艺腾 李磊 +2 位作者 谢良海 苟晓晨 冯永勇 《空间科学学报》 CAS CSCD 北大核心 2024年第2期299-308,共10页
能量中性原子(Energetic Neutral Atom,ENA)是由能量离子与中性背景成分电荷交换产生.火星的外逸层扩展范围远高于弓激波,上游太阳风质子与其相互作用并转化为太阳风氢ENA(Hydrogen-ENA,H-ENA),新生的H-ENA可直接进入低层大气,成为新的... 能量中性原子(Energetic Neutral Atom,ENA)是由能量离子与中性背景成分电荷交换产生.火星的外逸层扩展范围远高于弓激波,上游太阳风质子与其相互作用并转化为太阳风氢ENA(Hydrogen-ENA,H-ENA),新生的H-ENA可直接进入低层大气,成为新的物质与能量输运通道.本文基于单流体多成分MHD模型与中性外逸层模型,计算了火星200 km等高面沉降H-ENA通量的空间分布,统计了多种太阳风条件下沉降H-ENA的粒子与能量沉降率,分析影响因素.结果表明,在一定模拟条件下,产生于弓激波上游的太阳风H-ENA,呈cosZ分布(Z为天顶角),受磁异常影响较小,是沉降H-ENA的主要成分,占ENA总沉降量的59%,占能量沉降的81%;产生于磁鞘的磁鞘H-ENA受磁异常阻碍影响较大,在最强磁异常上方其沉降通量显著下降;沉降H-ENA与上游太阳风的通量呈正比例关系;2.1%~3.5%上游太阳风质子转化为太阳风H-ENA. 展开更多
关键词 火星 沉降h-ENA MhD模型 磁异常
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Effect of Aluminum Hydroxide Adjuvant on the Immunogenicity of the 2009 Pandemic Influenza A/H1N1 Vaccine:Multi-level Modeling of Data with Repeated Measures
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作者 YIN Da Peng ZHU Bao Ping +8 位作者 WANG Hua Qing CAO Lei WU Wen Di JIANG Ke Yu XIA Wei ZHANG Guo Min ZHENG Jing Shan CAO Ling Sheng LIANG Xiao Feng 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2011年第6期624-629,共6页
Objective To evaluate the effect of the aluminum hydroxide (Al-OH) adjuvant on the 2009 pandemic influenza A/H1N1 (pH1N1) vaccine. Methods In a multicenter, double-blind, randomized, placebo-controlled trial, part... Objective To evaluate the effect of the aluminum hydroxide (Al-OH) adjuvant on the 2009 pandemic influenza A/H1N1 (pH1N1) vaccine. Methods In a multicenter, double-blind, randomized, placebo-controlled trial, participants received two doses of split-virion formulation containing 15 ug hemagglutinin antigen, with or without aluminum hydroxide (N-OH). We classified the participants into six age categories (〉61 years, 41-60 years, 19-40 years, 13-18 years, 8-12 years, and 3-7 years) and obtained four blood samples from each participant on days 0, 21, 35, and 42 following the first dose of immunization. We assessed vaccine immunogenicity by measuring the geometric mean titer (GMT) of hemagglutination inhibiting antibody. We used a two-level model to evaluate the fixed effect of aluminum Al-OH and other factors, accounting for repeated measures. Results The predictions of repeated measurement on GMTs of formulations with or without Al-OH, were 80.35 and 112.72, respectively. Al-OH significantly reduced immunogenicity after controlling for time post immunization, age-group and gender. Conclusion The Al-OH adjuvant does not increase but actually reduces the immunogenicity of the split-virion pH1N1 vaccine. 展开更多
关键词 Aluminum hydroxide ADJUVANT IMMUNOGENICITY 2009 pandemic influenza A/h1N1 vaccine Multi-level model
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