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特征函数 1 ( 0,+∞ ) ( z )的一个光滑D.C.近似
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作者 修菀擎 陈浩东 任咏红 《应用数学进展》 2024年第7期3275-3280,共6页
特征函数1(0,+∞)(z)已经广泛地使用在实践中,许多重要的实际问题,如概率约束优化问题,可以表示为与特征函数相关的问题,该问题通常是非凸和非光滑的,因而在数值计算上有困难。本文构造了特征函数1(0,+∞)(z)的一个光滑D.C.近似函数。... 特征函数1(0,+∞)(z)已经广泛地使用在实践中,许多重要的实际问题,如概率约束优化问题,可以表示为与特征函数相关的问题,该问题通常是非凸和非光滑的,因而在数值计算上有困难。本文构造了特征函数1(0,+∞)(z)的一个光滑D.C.近似函数。讨论了函数φ(z,t)的一些性质。在一定条件下,当所涉及的参数足够小时,所提出的光滑近似函数收敛到1(0,+∞)(z)。基于该函数,构建了概率约束优化问题的一个等价的近似问题。 展开更多
关键词 特征函数 d.c.函数 光滑近似函数
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Applications of Computer Aided Modeling Techniques to Complex ICE Components 被引量:1
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作者 左正兴 冯慧华 +1 位作者 廖日东 邹文胜 《Journal of Beijing Institute of Technology》 EI CAS 2000年第4期451-458,共8页
Design of internal combustion engine (ICE) components is one of the earliest and also the most active areas in which computer aided modeling techniques are applied. Computer aided modeling techniques could provide req... Design of internal combustion engine (ICE) components is one of the earliest and also the most active areas in which computer aided modeling techniques are applied. Computer aided modeling techniques could provide requisite information for follow up designing segments such as structural analysis, design of technological process and manufacturing etc, and thereby lead to the reduction of product design period and the quality and reliability improvement of ICE components. So the developing situations of ICE components' 2 D drafting, 3 D modeling of ICE, overall CAD of ICE as well as component design expert system etc. are surveyed, which are the typical applications of computer aided modeling techniques in ICE component design process, and some existent problems and tasks are pointed out so as to make some references for the further research work. 展开更多
关键词 internal combustion engine(ICE) components computer aided modeling CAD 3 D model
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一类非凸D.C.约束优化问题的UV-分解理论 被引量:1
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作者 王炜 王雯 《大连民族学院学报》 CAS 2009年第3期229-231,234,共4页
UV-分解理论是近年来解决非光滑凸函数的二阶近似的一种有效的方法,并应用于解决非光滑凸函数的最优化问题。主要应用UV-分解理论对于一类D.C.函数的约束优化问题进行研究,借助于近似次微分的概念,得到类似的UV-空间分解,以及空间分解... UV-分解理论是近年来解决非光滑凸函数的二阶近似的一种有效的方法,并应用于解决非光滑凸函数的最优化问题。主要应用UV-分解理论对于一类D.C.函数的约束优化问题进行研究,借助于近似次微分的概念,得到类似的UV-空间分解,以及空间分解下的相应U-Lagrange函数与其最优解集W(u)的相关性质和二阶近似的结果。 展开更多
关键词 非光滑最优化 d.c.函数 UV-分解 U—Lagrange函数
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特征函数1_(0,+∞)(z)的一个光滑D.C.近似函数 被引量:2
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作者 任咏红 池慧 姜欢 《辽宁师范大学学报(自然科学版)》 CAS 2016年第4期438-442,共5页
基于Pinar-Zenios光滑和函数,提出了特征函数1(0,+∞)(z)的一个光滑D.C.近似函数,讨论了函数的性质,证明了当参数充分小时,光滑函数收敛于特征函数1(0,+∞)(z),并在一定的条件下,建立了概率约束优化问题的一个等价的光滑近似问题.
关键词 特征函数 Pinar-Zenios光滑和函数 d.c.函数 光滑近似
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D.C.隶属函数模糊集及其应用(II)——D.C.隶属函数模糊集的万能逼近性 被引量:3
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作者 邱中华 李雷 《模糊系统与数学》 CSCD 北大核心 2006年第2期50-60,共11页
本文是D.C.隶属函数模糊集及其应用系列研究的第二部分。指出在实际问题中普遍选用的三角形、半三角形、梯形、半梯形、高斯型、柯西型、S形、Z形、π形隶属函数模糊集等均为D.C.隶属函数模糊集,建立了D.C.隶属函数模糊集对模糊集的万... 本文是D.C.隶属函数模糊集及其应用系列研究的第二部分。指出在实际问题中普遍选用的三角形、半三角形、梯形、半梯形、高斯型、柯西型、S形、Z形、π形隶属函数模糊集等均为D.C.隶属函数模糊集,建立了D.C.隶属函数模糊集对模糊集的万有逼近性。探讨了D.C.隶属函数模糊集与模糊数之间的关系,给出了用D.C.隶属函数模糊集逼近模糊数的-εC e llina逼近形式,得到模糊数与D.C.函数之间的一个对应算子,指出了用模糊数表示D.C.函数的问题。 展开更多
关键词 d.c.隶属函数模糊集 逼近 模糊数
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D.C.隶属函数模糊集及其应用(I)——D.C.隶属函数模糊集基本概念与性质 被引量:4
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作者 李雷 《模糊系统与数学》 CSCD 北大核心 2005年第4期45-53,共9页
本文是D.C.隶属函数模糊集及其应用系列研究的第一部分。建立了D.C.隶属函数模糊集的基本概念。探讨了D.C.隶属函数模糊集的基本性质和D.C.隶属函数模糊集对一些常见的重要t模、余模和伪补的封闭性。并以此建立了丰富的模糊数学应用模型。
关键词 d.c.隶属函数 模糊集 T模 余模 伪补
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压缩感知中的概率约束优化模型及其D.C.近似
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作者 任咏红 曹丽娜 +1 位作者 姜欢 曲文静 《辽宁师范大学学报(自然科学版)》 CAS 2017年第2期154-158,共5页
带有噪声的压缩感知信号重建模型可表示为l_1-范数问题.为了满足使用少量观测值重构出高精度的图像,在设置观测矩阵时需要满足受限等距性(RIP)和非相干性,然而判断一个矩阵的RIP是非常困难的.针对观测矩阵的不确定性,将该模型转化为具... 带有噪声的压缩感知信号重建模型可表示为l_1-范数问题.为了满足使用少量观测值重构出高精度的图像,在设置观测矩阵时需要满足受限等距性(RIP)和非相干性,然而判断一个矩阵的RIP是非常困难的.针对观测矩阵的不确定性,将该模型转化为具有概率约束的随机优化模型,即在约束条件以很大的概率被满足的情况下,求解最小l_1-范数问题.构建了概率约束函数的一个D.C.近似函数,讨论了函数的性质,建立了相应的D.C.近似问题,证明了D.C.近似问题与概率约束优化问题的等价性. 展开更多
关键词 压缩感知 概率约束 d.c.近似
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概率约束优化问题的一个光滑D.C.近似 被引量:1
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作者 任咏红 曹丽娜 《辽宁师范大学学报(自然科学版)》 CAS 2018年第1期17-21,共5页
概率约束优化问题通常是非凸且非光滑的,因而在数值计算上存在困难.基于Pinar-Zenios光滑和函数,建立了概率约束优化问题的一个光滑D.C.近似问题,提出了求解光滑D.C.近似问题的序列凸近似(SCA)算法,分析了初始解的选取方法,并讨论了算... 概率约束优化问题通常是非凸且非光滑的,因而在数值计算上存在困难.基于Pinar-Zenios光滑和函数,建立了概率约束优化问题的一个光滑D.C.近似问题,提出了求解光滑D.C.近似问题的序列凸近似(SCA)算法,分析了初始解的选取方法,并讨论了算法的收敛性,收敛定理表明可以由SCA算法可以得到光滑D.C.近似问题的KKT点,并且在迭代过程中,确保了由SCA算法生成的解序列的极限点是近似问题的KKT点. 展开更多
关键词 概率约束 Pinar-Zenios光滑和函数 光滑d.c.近似 序列凸近似算法
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不可微D.C.规划问题的全局最优性充要条件 被引量:2
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作者 叶留青 《河南师范大学学报(自然科学版)》 CAS CSCD 2003年第2期15-17,共3页
本文给出了一类不可微D .C .
关键词 不可微d.c.规划 全局最优性 充要条件 Ε-最优解 非凸不可微规划 不可微凸函数
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Cortico-striatal gamma oscillations are modulated by dopamine D3 receptors in dyskinetic rats
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作者 Pengfei Wang Yuewei Bi +6 位作者 Min Li Jiazhi Chen Zhuyong Wang Huantao Wen Ming Zhou Minjie Luo Wangming Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第4期1164-1177,共14页
Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Cu... Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Currently,studies have reported increased oscillation power in cases of levodopa-induced dyskinesia.However,little is known about how the other electrophysiological parameters of gamma oscillations are altered in levodopa-induced dyskinesia.Furthermore,the role of the dopamine D3 receptor,which is implicated in levodopa-induced dyskinesia,in movement disorder-related changes in neural oscillations is unclear.We found that the cortico-striatal functional connectivity of beta oscillations was enhanced in a model of Parkinson’s disease.Furthermore,levodopa application enhanced cortical gamma oscillations in cortico-striatal projections and cortical gamma aperiodic components,as well as bidirectional primary motor cortex(M1)↔dorsolateral striatum gamma flow.Administration of PD128907(a selective dopamine D3 receptor agonist)induced dyskinesia and excessive gamma oscillations with a bidirectional M1↔dorsolateral striatum flow.However,administration of PG01037(a selective dopamine D3 receptor antagonist)attenuated dyskinesia,suppressed gamma oscillations and cortical gamma aperiodic components,and decreased gamma causality in the M1→dorsolateral striatum direction.These findings suggest that the dopamine D3 receptor plays a role in dyskinesia-related oscillatory activity,and that it has potential as a therapeutic target for levodopa-induced dyskinesia. 展开更多
关键词 aperiodic components dopamine D3 receptor dorsolateral striatum functional connectivity gamma oscillations levodopa-induced-dyskinesia local field potentials NEUROMODULATION Parkinson’s disease primary motor cortex
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求解一般D.C.规划的全局最优解
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作者 徐俊彦 苗壮 刘庆怀 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2013年第6期1058-1062,共5页
给出一种求解一般D.C.规划非孤立全局最优解的算法.该算法克服了目前一些逼近算法在计算过程中有时得到的解为不可行解、甚至远离真正全局最优解的问题.数值结果表明了算法的有效性.
关键词 全局优化 一般D C 规划 非孤立最优解
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Three-component seismic data in thin interbedded reservoir exploration
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作者 张丽艳 王彦春 裴江云 《Applied Geophysics》 SCIE CSCD 2015年第1期79-85,122,共8页
We present the first successful application of three-component seismic data to thin interbedded reservoir characterization in the Daqing placanticline of the LMD oilfield. The oilfield has reached the final high water... We present the first successful application of three-component seismic data to thin interbedded reservoir characterization in the Daqing placanticline of the LMD oilfield. The oilfield has reached the final high water cut stage and the principal problem is how to recognize the boundaries of sand layers that are thicker than 2 m. Conventional interpretation of single PP-wave seismic data results in multiple solutions, whereas the introduction of PS-wave enhances the reliability of interpretation. We analyze the gas reservoir characteristics by joint PP- and PS-waves, and use the amplitude and frequency decomposition attributes to delineate the gas reservoir boundaries because of the minimal effect of fl uids on S-wave. We perform joint inversion of PP- and PS-waves to obtain V P/V S, λρ, and μρ and map the lithology changes by using density, λρ, and μρ. The 3D–3C attribute λρ slices describe the sand layers distribution, while considering the well log data, and point to favorable region for tapping the remaining oil. 展开更多
关键词 3D–3C thin interbedded reservoirs gas reservoir characterization joint inversion tapping remaining oil
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D.C.乘性规划的全局优化算法
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作者 周雪刚 《长江大学学报(自然科学版)》 CAS 2011年第4期1-4,284,共4页
讨论了凸集上的D.C.乘性规划的全局优化算法。首先通过引入辅助变量将D.C.乘性规划问题转化为一个等价的D.C.规划问题;再综合利用分支定界与外逼近方法求解等价问题;最后用一个实例说明算法的实用性。
关键词 d.c.乘性规划 全局优化 割平面 锥细分
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Additive Manufacture of Ceramics Components by Inkjet Printing 被引量:18
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作者 Brian Derby 《Engineering》 SCIE EI 2015年第1期113-123,共11页
In order to build a ceramic component by inkjet printing, the object must be fabricated through the interaction and solidification of drops, typically in the range of 10–100 p L. In order to achieve this goal, stable... In order to build a ceramic component by inkjet printing, the object must be fabricated through the interaction and solidification of drops, typically in the range of 10–100 p L. In order to achieve this goal, stable ceramic inks must be developed. These inks should satisfy specific rheological conditions that can be illustrated within a parameter space defined by the Reynolds and Weber numbers. Printed drops initially deform on impact with a surface by dynamic dissipative processes, but then spread to an equilibrium shape defined by capillarity. We can identify the processes by which these drops interact to form linear features during printing, but there is a poorer level of understanding as to how 2D and 3D structures form. The stability of 2D sheets of ink appears to be possible over a more limited range of process conditions that is seen with the formation of lines. In most cases, the ink solidifies through evaporation and there is a need to control the drying process to eliminate the "coffee ring" defect. Despite these uncertainties, there have been a large number of reports on the successful use of inkjet printing for the manufacture of small ceramic components from a number of different ceramics. This technique offers good prospects as a future manufacturing technique. This review identifies potential areas for future research to improve our understanding of this manufacturing method. 展开更多
关键词 additive manufacture 3D printing inkjet printing ceramic components
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Determination of bioactive components in the fruits of Cercis chinensis Bunge by HPLC-MS/MS and quality evaluation by principal components and hierarchical cluster analyses 被引量:6
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作者 Yuan Hong Xiaoyan Liao Zilin Chen 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2021年第4期465-471,共7页
The fruits of leguminous plants Cercis Chinensis Bunge are still overlooked although they have been reported to be antioxidative because of the limited information on the phytochemicals of C.chinensis fruits.A simple,... The fruits of leguminous plants Cercis Chinensis Bunge are still overlooked although they have been reported to be antioxidative because of the limited information on the phytochemicals of C.chinensis fruits.A simple,rapid and sensitive HPLC-MS/MS method was developed for the identification and quantitation of the major bioactive components in C.chinensis fruits.Eighteen polyphenols were identified,which are first reported in C.chinensis fruits.Moreover,ten components were simultaneously quantified.The validated quantitative method was proved to be sensitive,reproducible and accurate.Then,it was applied to analyze batches of C.chinensis fruits from different phytomorph and areas.The principal components analysis(PCA)realized visualization and reduction of data set dimension while the hierarchical cluster analysis(HCA)indicated that the content of phenolic acids or all ten components might be used to differentiate C.chinensis fruits of different phytomorph. 展开更多
关键词 C.chinensis fruits HPLC-MS/MS POLYPHENOLS Principal components analysis Hierarchical cluster analysis
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基于最优D.C.分解的单二次约束非凸二次规划精确算法 被引量:2
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作者 郑小金 《运筹学学报》 CSCD 2009年第3期111-118,共8页
本文提出一种基于最优D.C.分解的单二次约束非凸二次规划精确算法.本文首先对非凸二次目标函数进行D.C.分解,然后对D.C.分解中凹的部分进行线性下逼近得到一个凸二次松弛问题.本文证明了最优D.C.分解可通过求解一个半定规划问题得到,而... 本文提出一种基于最优D.C.分解的单二次约束非凸二次规划精确算法.本文首先对非凸二次目标函数进行D.C.分解,然后对D.C.分解中凹的部分进行线性下逼近得到一个凸二次松弛问题.本文证明了最优D.C.分解可通过求解一个半定规划问题得到,而原问题的最优解可以通过计算最优凸二次松弛问题的满足某种互补条件的解得到.最后,本文报告了初步数值计算结果. 展开更多
关键词 运筹学 单二次约束非凸二次规划问题 最优d.c.分解 半定规划 精确算法
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Design, Analysis and R&D of the EAST In-Vessel Components 被引量:2
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作者 姚达毛 鲍立曼 +15 位作者 李建刚 宋云涛 陈文革 杜世俊 胡庆生 卫靖 谢韩 刘旭峰 曹磊 周自波 陈俊凌 毛心桥 王声铭 祝宁 翁佩德 万元熙 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第3期367-372,共6页
In-vessel components are important parts of the EAST superconducting tokamak. They include the plasma facing components, passive plates, cryo-pumps, in-vessel coils, etc. The structural design, analysis and related R... In-vessel components are important parts of the EAST superconducting tokamak. They include the plasma facing components, passive plates, cryo-pumps, in-vessel coils, etc. The structural design, analysis and related R&D have been completed. The divertor is designed in an up-down symmetric configuration to accommodate both double null and single null plasma operation. Passive plates are used for plasma movement control. In-vessel coils are used for the active control of plasma vertical movements. Each cryo-pump can provide an approximately 45 m^3/s pumping rate at a pressure of 10^-1 Pa for particle exhaust. Analysis shows that, when a plasma current of 1 MA disrupts in 3 ms, the EM loads caused by the eddy current and the halo current in a vertical displacement event (VDE) will not generate an unacceptable stress on the divertor structure. The bolted divertor thermal structure with an active cooling system can sustain a load of 2 MW/m^2 up to a 60 s operation if the plasma facing surface temperature is limited to 1500 ℃. Thermal testing and structural optimization testing were conducted to demonstrate the analysis results. 展开更多
关键词 EAST superconducting tokamak in-vessel components structure design and analyses thermal analyses related R&D
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The Convergence of the Steepest Descent Algorithm for D.C.Optimization 被引量:1
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作者 SONG Chun-ling XIA Zun-quan 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第1期131-136,共6页
Some properties of a class of quasi-differentiable functions(the difference of two finite convex functions) are considered in this paper. And the convergence of the steepest descent algorithm for unconstrained and c... Some properties of a class of quasi-differentiable functions(the difference of two finite convex functions) are considered in this paper. And the convergence of the steepest descent algorithm for unconstrained and constrained quasi-differentiable programming is proved. 展开更多
关键词 nonsmooth optimization D. C. optimization upper semi-continuous lower semi-continuous steepest descent algorithm CONVERGENCE
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GENERIC STABILITY AND EXISTENCE OF ESSENTIAL COMPONENTS OF THE SOLUTION SET FOR THE SYSTEM OF GENERALIZED VECTOR EQUILIBRIUM PROBLEMS 被引量:1
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作者 Lin Zhi Yu Jian 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2007年第4期497-504,共8页
By using Fort theorem the generic stability result for the system of generalized vector equilibrium problems is established. Further, by proving the existence and connectivity of minimal essential set the existence re... By using Fort theorem the generic stability result for the system of generalized vector equilibrium problems is established. Further, by proving the existence and connectivity of minimal essential set the existence result of essential components in the solution set is derived. 展开更多
关键词 system of generalized vector equilibrium problems C-convex C-continuous essential component.
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引用“P.D.C.A循环法”实施对护士长管理能力培训的体会 被引量:3
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作者 尹凤英 《国际医药卫生导报》 2001年第10A期14-14,共1页
目的 提高护士长综合管理能力。方法 引用质量管理中的“P.D.C.A循环法”通过对护士长进行(1)现代管理基础理论,护理管理知识学习;(2)实行护士长目标责任制管理;(3)新任职护士长轮岗制度。效果 (1)11名护士长年度业绩考核,优秀3名占27%... 目的 提高护士长综合管理能力。方法 引用质量管理中的“P.D.C.A循环法”通过对护士长进行(1)现代管理基础理论,护理管理知识学习;(2)实行护士长目标责任制管理;(3)新任职护士长轮岗制度。效果 (1)11名护士长年度业绩考核,优秀3名占27%,称职7名,基本称职1名;(2)与97年相比全年护理质量综合评分上升至98.2%,护理事故及严重差错发生率为0,患者满意度上升至96.7%。九八年被评为百佳医院。结论 护理部要把人才培养放在选拔之前,运用质量循环管理精神不断提高护士长自身素质及管理能力,使之成为具有丰富管理知识的临床专家型护理管理者,以适应新的时期护理工作发展的需要。 展开更多
关键词 “P.d.c.A循环法” 护士长 管理能力 培训
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