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早期CRRT干预对行集束化治疗重症社区获得性肺炎患者实验室及预后指标的影响

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罕少疾病杂志 2023年第5期30卷 35-36页

作者：王道协段文慧梁瑞静赵亮李国吾文建国郑州市第三人民医院重症医学科河南郑州450000 郑州大学第一附属医院尿流动力学中心/河南省临床医学重点学科开放实验室河南郑州450000

目的探讨早期CRRT干预对行集束化治疗重症社区获得性肺炎患者实验室及预后指标的影响。方法回顾性分析我院2013年1月至2019年12月收治重症社区获得性肺炎患者共84例临床资料,其中仅给予集束化治疗共44例设为对照组,在集束化治疗基础上... 详细信息

目的探讨早期CRRT干预对行集束化治疗重症社区获得性肺炎患者实验室及预后指标的影响。方法回顾性分析我院2013年1月至2019年12月收治重症社区获得性肺炎患者共84例临床资料,其中仅给予集束化治疗共44例设为对照组,在集束化治疗基础上加用早期CRRT干预共40例设为观察组;比较两组治疗前后PCT、TNF-α、IL-6、CD4+T淋巴细胞亚群水平、ARDS发生率及死亡率。结果观察组治疗后PCT、TNF-α及IL-6水平均显著少于对照组、治疗前(P<0.05);观察组治疗后CD4+T淋巴细胞亚群水平均显著高于对照组、治疗前(P<0.05);观察组7d内ARDS发生率和死亡率显著低于对照组(P<0.05)。结论早期CRRT干预用于行集束化治疗重症社区获得性肺炎患者可有效抑制炎症细胞因子释放,增强机体免疫系统功能,并有助于改善临床预后。

关键词： CRRT 集束化社区获得性肺炎实验室预后

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Reliability-based selective maintenance for redundant systems with dependent performance characteristics of components

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Journal of Systems Engineering and Electronics 2023年第3期34卷 804-814页

作者： CAO hui duan Fuhai duan Yu’nan School of Mechanical Engineering Dalian University of TechnologyDalian 116024China

The reliability-based selective maintenance(RSM)decision problem of systems with components that have multiple dependent performance characteristics(PCs)reflecting degradation states is addressed in this paper.A vine-Copulabased reliability evaluation method is proposed to estimate the reliability of system components with multiple ***,the marginal degradation reliability of each PC is built by using the Wiener stochastic process based on the PC’s degradation *** joint degradation reliability of the component with multiple PCs is established by connecting the marginal reliability of PCs using *** addition,two RSM decision models are developed to ensure the system accomplishes the next *** genetic algorithm(GA)is used to solve the constraint optimization problem of the models.A numerical example illustrates the application of the proposed RSM method.

关键词： D-vine genetic algorithm(GA) reliability-based selective maintenance(RSM) redundant system Wiener stochastic process

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小湾水电站进水口高边坡监测及信息反馈研究

地下空间与工程学报 2006年第6期2卷 1025-1028,1033页

作者：黄仕俊赵华段会文董泽荣张援征中国水电顾问集团昆明勘测设计研究院科学研究分院昆明650033 中国水电顾问集团西北勘测设计研究院西安710043

针对小湾水电站垂直开挖高度81m进水口直立边坡大量监测资料,结合变形、地质、开挖和加固处理影响因素,分析了边坡变形特征;评价了以f 3为控制性底滑面不稳定楔形体的加固效果以及对抑制卸荷松弛变形作用;通过监测信息反馈,设计有针对... 详细信息

针对小湾水电站垂直开挖高度81m进水口直立边坡大量监测资料,结合变形、地质、开挖和加固处理影响因素,分析了边坡变形特征;评价了以f 3为控制性底滑面不稳定楔形体的加固效果以及对抑制卸荷松弛变形作用;通过监测信息反馈,设计有针对性地及时进行边坡动态支护优化,使预应力锚索达到了较佳工作状态,充分发挥了锚固作用。

关键词：直立高边坡监测信息反馈动态支护小湾水电站

Using a pre-kicker to ensure safe extractions from the HEPS storage ring

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Nuclear Science and Techniques 2021年第12期32卷 26-36页

作者： Zhe duan Jin-hui Chen Hua Shi Guang-Yi Tang Lei Wang Yu-wen Wu Key Laboratory of Particle Acceleration Physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Dongguan Neutron Science Center Dongguan 523800China

The High Energy Photon Source(HEPS)is a 6 GeV diffraction-limited storage ring light source under *** swap-out injection is adopted with the depleted bunch recycled via high-energy accumulation in the *** extremely high beam energy density of the bunches with an ultra-low emittance(about 30 pm horizontally and 3 pm vertically)and high bunch charges(from 1.33 to 14.4 nC)extracted from the storage ring could cause hazardous damage to the extraction Lambertson magnet in case of extraction kicker *** this end,we proposed the use of a pre-kicker to spoil the bunches prior to extraction,significantly reducing the maximum beam energy density down to within a safe region while still maintaining highly efficient *** main parameters of the pre-kicker are simulated and discussed.

关键词： Pre-kicker The high energy photon source Intense electron beam Diffraction-limited storage ring Extraction Lambertson magnet

晶闸管三相半控整流电路谐波耦合导纳矩阵建模算法研究

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电力系统装备 2020年第13期 37-38,167页

作者：陈宏军段文辉王克谦王鹏魏继承河南省电力公司信阳供电公司河南信阳464000

在研究优化的全网谐波抑制方法时,非线性负荷建模是影响精度和效率的关键.文章针对三相阻感负载整流电路的原理进行分析,并采用具有高精度的谐波耦合导纳矩阵模型算法进行建模,从而准确地预测不同负载参数下,其各次谐波耦合程度的变化规... 详细信息

在研究优化的全网谐波抑制方法时,非线性负荷建模是影响精度和效率的关键.文章针对三相阻感负载整流电路的原理进行分析,并采用具有高精度的谐波耦合导纳矩阵模型算法进行建模,从而准确地预测不同负载参数下,其各次谐波耦合程度的变化规律,为研究非线性负载谐波外特性提供了一种解决方案.文章对所提谐波耦合导纳矩阵的建模方法,进行了仿真和实验验证,仿真数据及实验结果均验证了该方法对晶闸管三相半控整流电路谐波外特性拟合的准确性.

关键词：耦合导纳矩阵非线性负载三相全桥晶闸管整流电路电能质量优化

Phase evolution of binary immiscible Al-Sn film

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Rare Metals 2022年第12期41卷 4241-4247页

作者： Xiao-Meng Pan hui-Ping duan School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Binary immiscible Al-Sn alloy is a very important potential anode material for lithium ion *** phase stability and separation process of Al-Sn film,fabricated by magnetron co-sputtering method,was investigated by X-ray diffractometer(XRD),differential scanning calorimetry(DSC) and in situ transmission electron microscopy(TEM) and explained by Miedema theoretical *** analysis reveals that the asdeposited Al-Sn film will decompose spontaneously into Al-riched areas and Sn-riched areas because of the positive mixing *** crystallization process takes place when the Al content in the Al-riched area or Sn content in the Sn-riched area *** results show that Al-Sn thin film is composed of an amorphous matrix and well-dispersed composite *** particle contains an Al-riched area and a Sn-riched *** Snriched area crystallizes and swallows up the Al-riched area gradually during heating through uphill diffusion of the Sn *** on the theoretical analysis and experimental results,an empirical model to explain the phase evolution process in the Al-Sn film was proposed.

关键词： Immiscible alloy Uphill diffusion Phase evolution Miedema theory

Three-dimensional numerical analysis on combustion performance and flow of hybrid rocket motor with multi-segmented grain

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Chinese Journal of Aeronautics 2020年第4期33卷 1181-1191页

作者： hui TIAN Yu duan Hao ZHU School of Astronautics Beihang UniversityBeijing 100083China Key Laboratory of Spacecraft Design Optimization&Dynamic Simulation Technologies Ministry of EducationBeihang UniversityBeijing 100083China

This paper presents the combustion characteristics in hybrid rocket motors with multisegmented grain through three-dimensional numerical ***-segmented grain is composed of several thin grains with two or more *** numerical model consists of Navier-Stokes equations with turbulence,solid fuel pyrolysis,chemical reactions,a fluid–solid coupling model and a regression rate *** simulations adopt 90%Hydrogen Peroxide(HP)and PolyEthylene(PE)as the propellant *** effects of the rotation,port number,fuel grain segment number and mid-chamber length on the flow field and combustion performances are *** results indicate that the multi-segmented grain configuration can strengthen the flow field,and the regression rate and combustion efficiency are *** the cases with two grain segments and three ports for example,the regression rate is increased by 32.4%-45.1%and the combustion efficiency increases by 6%-8.6%in different rotation angles.

关键词： Combustion efficiency Hybrid rocket motor Multi-segmented grain Regression rate Rotation angle

Formation Mechanism of the Accumulative Magnification Effect in a Financial Time Series

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Chinese Physics Letters 2012年第3期29卷 271-274页

作者： duan wen-Qi College of Economics and Management Zhejiang Normal UniversityJinhua 321004

Structural information contained in financial time series can be magnified effectively by constructing the accumulative *** order to make the magnification effects of different financial time series comparative,we first propose a standard method to characterize the strength of the accumulative magnification ***,we employ decomposed-randomized technology to uncover the formation mechanism of the accumulative magnification *** results show that(1)the standard deviation pattern is determined by volatility dependence,(2)the Hurst exponent pattern is induced by sign dependence,(3)an approximate entropy pattern is caused by the combined effect of sign dependence and volatility dependence.

关键词： effect strength pattern

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采用滑动测微计监测坝基岩体卸荷变形

地下空间与工程学报 2006年第6期2卷 1014-1018,1024页

作者：董泽荣赵华黄仕俊段会文廖建军李仕胜姜云辉中国水电顾问集团昆明勘测设计研究院科学研究分院昆明650033 中国水利水电科学研究院北京100044

介绍了瑞士高精度滑动测微计监测沿钻孔中应变分布的原理和方法;采用滑动测微计成功监测了小湾坝基开挖及混凝土压重状态下的岩体卸荷变形,探测卸荷裂隙分布和张开位移量,定量分析了坝基卸荷岩体变形发展规律,为评价坝基岩体质量和调整... 详细信息

介绍了瑞士高精度滑动测微计监测沿钻孔中应变分布的原理和方法;采用滑动测微计成功监测了小湾坝基开挖及混凝土压重状态下的岩体卸荷变形,探测卸荷裂隙分布和张开位移量,定量分析了坝基卸荷岩体变形发展规律,为评价坝基岩体质量和调整坝基岩体力学参数提供了依据,可供类似工程参考。

关键词：坝基岩体卸荷变形滑动测微计监测小湾电站