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说柔、用柔、柔实力 被引量:8
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作者 叶自成 《社会科学》 CSSCI 北大核心 2017年第3期118-129,共12页
老子的"柔弱胜刚强"及从中延伸的柔实力,是老子治国之术的重要组成部分。柔弱在《老子》一书中有五种不同的含义;"柔弱胜刚强"并非力量弱小胜力量强大,"柔弱"是力量的柔性使用;老子提出的"柔"... 老子的"柔弱胜刚强"及从中延伸的柔实力,是老子治国之术的重要组成部分。柔弱在《老子》一书中有五种不同的含义;"柔弱胜刚强"并非力量弱小胜力量强大,"柔弱"是力量的柔性使用;老子提出的"柔"概念实质上是一种柔实力;在中国历史上柔实力有丰富的实践。柔弱与刚强,亦如一阴一阳,一正一奇,形成了治理国家的两个方面,刚柔并济是正道。柔实力可以为今天国家治理和天下治理提供有益的思想基因。 展开更多
关键词 老子 政治哲学 柔弱 实力
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实力 道理 规律
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作者 林昊 《中小企业管理与科技》 2007年第7期5-5,共1页
实力,道理,规律,把这三个词放在一起,似乎风马牛不相及,其实三者的关系密不可分,也是每个人都离不开的。
关键词 中国 当代 散文 作品赏析 《实力 道理 规律》
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小故事里的大智慧
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作者 周正 《企业管理》 CSSCI 北大核心 2009年第11期89-89,共1页
某公司招聘一名维修部主管,在经过几轮残酷的淘汰考核之后,应聘人数从几十人落到最后两人,他们分别是小张和小李。
关键词 智慧 故事 《实力之外定成败》 《扶树与扶人》
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FLOW STRESS MODELING FOR AERONAUTICAL ALUMINUM ALLOY 7050-T7451 IN HIGH-SPEED CUTTING 被引量:15
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作者 付秀丽 艾兴 +1 位作者 万熠 张松 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第2期139-144,共6页
The high temperature split Hopkinson pressure bar (SHPB) compression experiment is conducted to obtain the data relationship among strain, strain rate and flow stress from room temperature to 550 C for aeronautical ... The high temperature split Hopkinson pressure bar (SHPB) compression experiment is conducted to obtain the data relationship among strain, strain rate and flow stress from room temperature to 550 C for aeronautical aluminum alloy 7050-T7451. Combined high-speed orthogonal cutting experiments with the cutting process simulations, the data relationship of high temperature, high strain rate and large strain in high-speed cutting is modified. The Johnson-Cook empirical model considering the effects of strain hardening, strain rate hardening and thermal softening is selected to describe the data relationship in high-speed cutting, and the material constants of flow stress constitutive model for aluminum alloy 7050-T7451 are determined. Finally, the constitutive model of aluminum alloy 7050-T7451 is established through experiment and simulation verification in high-speed cutting. The model is proved to be reasonable by matching the measured values of the cutting force with the estimated results from FEM simulations. 展开更多
关键词 high-speed cutting flow stress models SHPB compression experiment FEM simulation
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COMPENSATION CONTROL OF REAL-TIME UNBALANCE FORCE FOR ACTIVE MAGNETIC BEARING SYSTEM 被引量:2
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作者 高辉 徐龙祥 朱益利 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第2期183-191,共9页
Aiming at the stability and others properties of active magnetic bearing (AMB) system influenced by the periodic unbalance stimulation synchronous with rotor rotational speed, a new real-time adaptive feed-forward u... Aiming at the stability and others properties of active magnetic bearing (AMB) system influenced by the periodic unbalance stimulation synchronous with rotor rotational speed, a new real-time adaptive feed-forward unbalance force compensation scheme is proposed based on variable step-size least mean square(LMS) algorithm as the feed-forward compensation controller. The controller can provide some suitable sinusoidal signals to com- pensate the feedback unbalance response signals synchronous with the rotary frequency, then reduce the fluctua- tion of the control currents and weaken the active control of AMB system. The variable step-size proportional to the rotational frequency is deduced by analyzing the principle of normal LMS algorithm and its deficiency in the application of real-time filtering of AMB system. Experimental results show that the new method can implement real-time unbalance force compensation in a wide frequency band, reduce the effect of unbalance stimulant force on the housing of AMB system, and provide convenience to improve rotational speed. 展开更多
关键词 active magnetic bearing variable step-size LMS algorithm bandwidth~ real-time unbalance forcecompensation~ adaptive filter
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A formation pressure prediction method based on tectonic overpressure
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作者 申波 张超谟 +1 位作者 毛志强 肖承文 《Applied Geophysics》 SCIE CSCD 2010年第4期376-383,401,共9页
Traditional formation pressure prediction methods all are based on the formation undercompaction mechanism and the prediction results are obviously low when predicting abnormally high pressure caused by compressional ... Traditional formation pressure prediction methods all are based on the formation undercompaction mechanism and the prediction results are obviously low when predicting abnormally high pressure caused by compressional structure overpressure.To eliminate this problem,we propose a new formation pressure prediction method considering compressional structure overpressure as the dominant factor causing abnormally high pressure.First,we establish a model for predicting maximum principal stress,this virtual maximum principal stress is calculated by a double stress field analysis.Then we predict the formation pressure by fitting the maximum principal stress with formation pressure. The real maximum principal stress can be determined by caculating the sum of the virtual maximum principal stresses.Practical application to real data from the A1 and A2 wells in the A gas field shows that this new method has higher accuracy than the traditional equivalent depth method. 展开更多
关键词 formation pressure UNDERCOMPACTION tectonic stress maximum principal stress conventional log data
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Experimental analysis of the slip sinkage effect based on real vehicle test 被引量:1
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作者 杨帆 林国余 +1 位作者 张为公 王宁波 《Journal of Southeast University(English Edition)》 EI CAS 2016年第2期201-207,共7页
To improve the semi-empirical model, the slip sinkage effect is analyzed based on the real vehicle test. A dynamic testing system is used to gain the dynamic responses of wheel-soil interactions, The Gauss-Newton algo... To improve the semi-empirical model, the slip sinkage effect is analyzed based on the real vehicle test. A dynamic testing system is used to gain the dynamic responses of wheel-soil interactions, The Gauss-Newton algorithm is adopted to estimate the undetermined parameters involved in the slip sinkage models. Wong's original model is compared with three typical slip sinkage models on the prediction performance of a drawbar pull. The maximum error rate, root mean squared error and correlation coefficient are utilized to evaluate the performance. The results indicate that the slip sinkage models outperform Wong's model and greatly improve the prediction accuracy. Lyasko's model is confirmed as an outstanding one for its comprehensive performance. Hence, the existence of the slip sinkage effect is validated. Lyasko's model is selected as an optimal one for the practical evaluation of military vehicle trafficability. 展开更多
关键词 vehicle trafficability slip sinkage effect Gauss-Newton algorithm real vehicle test wheel force transducer
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Preliminary Study of Low Self-fertile Rate of ‘Kuijin' Apricot
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作者 韩雪平 薛晓敏 王金政 《Agricultural Science & Technology》 CAS 2016年第4期810-813,共4页
To research the self-sterility of apricot, the pollen germination of ‘Kuijin'apricot was conducted in vitro, and pollen viability was determined by germination on solid medium. Meanwhile, the effects of different me... To research the self-sterility of apricot, the pollen germination of ‘Kuijin'apricot was conducted in vitro, and pollen viability was determined by germination on solid medium. Meanwhile, the effects of different media on its pollen germination and the growth of pollen tubes were analyzed. The results showed that the optimum media for pollen germination and growth of pollen tubes were 10% sucrose +0.1% boric acid and 5% sucrose + 0.01% boric acid respectively. The self-pollination setting rate of ‘Kuijin' apricot was 4.70%, indicating that ‘Kuijin' apricot was self-incompatible. The reasons for the self-incompatibility of ‘Kuijin' were explored according to its pollen weight and pollen quantity. The results showed that self-pollinate setting rate of ‘Kuijin' apricot was closely related to the length of pollen tubes,but it had no direct correlation with pollen quantity. 展开更多
关键词 APRICOT Pollen quantity Pollen viability Self-fertile setting
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Intelligent Examination Monitoring and Maintenance for the Safety of Operation of Flexible Manufacturing Systems
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作者 张建民 李世健 郝娟 《Journal of Beijing Institute of Technology》 EI CAS 2001年第2期163-168,共6页
Based on the system of electric power supply for flexible manufacturing systems (FMS), a study has been carried out on the intelligent safety examination, monitoring and maintenance of its running environment. On the ... Based on the system of electric power supply for flexible manufacturing systems (FMS), a study has been carried out on the intelligent safety examination, monitoring and maintenance of its running environment. On the basis of the specific feature of the power supply network of an FMS, real time monitoring system of the power supply network and the fault diagnostic expert system for the power equipment have been designed. This system can diagnose not only definite fault phenomena, but also fuzzy, uncertain fault phenomena as well. Fault diagnostic knowledge base for the power equipment has been founded hierarchy architecture model and the method of fault tree analysis. Feasibility of this system has been proved by computer simulation. 展开更多
关键词 flexible manufacturing systems power supply network power equipment real time monitoring fault diagnosis expert system
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Establishment and application of logging saturation interpretation equation in vuggy reservoirs 被引量:3
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作者 孙文杰 李宁 +2 位作者 武宏亮 王克文 张宫 《Applied Geophysics》 SCIE CSCD 2014年第3期257-268,350,共13页
Vuggy reservoirs are the most common, albeit important heterogeneous carbonate reservoirs in China. However, saturation calculations using logging data are not well developed, whereas Archie method is more common. In ... Vuggy reservoirs are the most common, albeit important heterogeneous carbonate reservoirs in China. However, saturation calculations using logging data are not well developed, whereas Archie method is more common. In this study, electrical conduction in a vuggy reservoir is theoretically analyzed to establish a new saturation equation for vuggy reservoirs. We found that vugs have a greater effect on saturation than resistivity, which causes inflection in the rock-electricity curve. Using single-variable exPeriments, we evaluated the effects of rug size, vug number, and vug distribution on the rock-electricity relation. Based on the general saturation model, a saturation equation for vuggy reservoirs is derived, and the physical significance of the equation parameters is discussed based on the seepage-electricity similarity. The equation parameters depend on the pore structure, and vugs and matrix pore size distribution. Furthermore, a method for calculating the equation parameters is proposed, which uses nuclear magnetic resonance (NMR) data to calculate the capillary pressure curve. Field application of the proposed equation and parameter derivation method shows good match between calculated and experimental results, with an average absolute error of 5.8%. 展开更多
关键词 Vuggy reservoir SATURATION general solution saturation equation capillary pressure capillary pressure curve NMR rock electricity.
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Hardware-in-loop Simulation(HLS) of Homing Anti-tank Missile 被引量:1
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作者 宋建梅 张天桥 《Journal of Beijing Institute of Technology》 EI CAS 1996年第1期49-54,共6页
The simulation techniques of hardware-in-loop simulation(HLS) of homing antitank missile based on the personal computer (PC) are discussed. The PC and MCS-96 chip controller employ A/D and D/A boards (with photoelectr... The simulation techniques of hardware-in-loop simulation(HLS) of homing antitank missile based on the personal computer (PC) are discussed. The PC and MCS-96 chip controller employ A/D and D/A boards (with photoelectricity isolation) to transfer measur ment and control information about homing head, gyro and rudder and utilize the digital hand shaking board to build correct communication communication protocol. In order to satisfy the real-time requirement of HLS, this paper first simplifies the aerodynamic data file reasonably, then builds a PC software with C language. The program of the controller part is made with PL/M language. The simulation of HLS based on PC is done with the same sampling period of 10ms as that of YH-F1 and the experiment results are identical to those of digital simulation of the homing anti-tank guided missile. 展开更多
关键词 HARDWARE-IN-LOOP SIMULATION communication protocol aerodynamic data
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Growth and Competition of Fourteen Herb Species in Experimental Microcoenosiums 被引量:1
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作者 陈章和 《Acta Botanica Sinica》 CSCD 2001年第11期1184-1190,共7页
Growth and competition of 14 herb species were investigated in the experimental microcoenosiums in laboratory under the following environmental factors and treatment levels: high and low fertility, clipping and un-cli... Growth and competition of 14 herb species were investigated in the experimental microcoenosiums in laboratory under the following environmental factors and treatment levels: high and low fertility, clipping and un-clipping, and with and without microbial infusion. The most intense competition and the biggest difference in biomass among the species were detected in the high fertility microcoenosiums subjected to no clipping disturbance. Clippings or low fertility reduced the growth of the competitors and resulted in more even biomass distribution among the species. Successive clippings reduced the total accumulative biomass of the microcoenosiums. Microbial infusion significantly increased the growth of legume species Lotus corniculatus L. and Trifolium pratense L. The growth of Alopecurus pratensis L. was also raised by microbial infusion, whereas Dactylis glomerata L. had more biomass in without-microbial-infusion microcoenosiums than in microbial infusion ones. Most of the 14 species were not obviously affected. The positive effect of microbial infusion was more marked in the low fertility microcoenosiums. 展开更多
关键词 herb species experimental microcoenosiums GROWTH COMPETITION
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从日元国际化的经验教训看人民币国际化 被引量:3
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作者 鲁昕 《知识经济》 2010年第13期53-53,共1页
人民币国际化问题日益成为关注的焦点。近些年来,人民币国际化步伐进一步加快,从人民币结算试点、上海国际金融中心建设到中国-东盟自由贸易区的建成,人民币正稳步向国际化目标迈进。作为一个与我国在社会文化、对外贸易、国际地位等方... 人民币国际化问题日益成为关注的焦点。近些年来,人民币国际化步伐进一步加快,从人民币结算试点、上海国际金融中心建设到中国-东盟自由贸易区的建成,人民币正稳步向国际化目标迈进。作为一个与我国在社会文化、对外贸易、国际地位等方面有着诸多相似点的国家,日本为推进日元国际化所做出的努力值得借鉴,同时日元国际化的深刻教训也值得我们好好总结。 展开更多
关键词 人民币国际化 日元国际化 经济实力 金融市场
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Edge detection in the potential field using the correlation coefficients of multidirectional standard deviations 被引量:5
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作者 徐梦龙 杨长保 +2 位作者 吴燕冈 陈竞一 郇恒飞 《Applied Geophysics》 SCIE CSCD 2015年第1期23-34,120,121,共14页
Most edge-detection methods rely on calculating gradient derivatives of the potential field, a process that is easily affected by noise and is therefore of low stability. We propose a new edge-detection method named c... Most edge-detection methods rely on calculating gradient derivatives of the potential field, a process that is easily affected by noise and is therefore of low stability. We propose a new edge-detection method named correlation coefficient of multidirectional standard deviations(CCMS) that is solely based on statistics. First, we prove the reliability of the proposed method using a single model and then a combination of models. The proposed method is evaluated by comparing the results with those obtained by other edge-detection methods. The CCMS method offers outstanding recognition, retains the sharpness of details, and has low sensitivity to noise. We also applied the CCMS method to Bouguer anomaly data of a potash deposit in Laos. The applicability of the CCMS method is shown by comparing the inferred tectonic framework to that inferred from remote sensing(RS) data. 展开更多
关键词 Edge detection Correlation coefficient multidirectional standard deviation Bouguer anomaly
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Accuracy analysis of plane-strain bulge test for determining mechanical properties of thin films 被引量:3
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作者 杨林 龙士国 +1 位作者 马增胜 王子菡 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第10期3265-3273,共9页
The effect of a variety of geometrics, initial conditions and material properties on the deformation behavior of thin films in the plane-strain bulge test was systematically scrutinized by performing the finite elemen... The effect of a variety of geometrics, initial conditions and material properties on the deformation behavior of thin films in the plane-strain bulge test was systematically scrutinized by performing the finite element analysis, and then the accuracy of the plane-strain bulge test in determining the mechanical properties of thin films in terms of our finite element results was analyzed. The results indicate that although the determination of the plane-strain modulus in the light of the plane-strain bulge equation is fairly accurate, the calculation of the residual stress is not satisfied as expected, especially for low residual stress. Finally, an approach is proposed for analyzing bulge test data, which will improve the accuracy and reliability of this bulge test technique. 展开更多
关键词 thin films mechanical properties bulge test ACCURACY finite element analysis
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Finite element failure analysis of continuous prestressed concrete box girders 被引量:4
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作者 张峰 李术才 +2 位作者 李树忱 叶见曙 雷笑 《Journal of Southeast University(English Edition)》 EI CAS 2009年第2期236-240,共5页
In order to analyze the load carrying capacity of prestressed concrete box girders, failure behaviors of in-situ deteriorated continuous prestressed concrete box girders under loading are experimentally observed and a... In order to analyze the load carrying capacity of prestressed concrete box girders, failure behaviors of in-situ deteriorated continuous prestressed concrete box girders under loading are experimentally observed and a finite failure analysis method for predicting behaviors of box girders is developed. A degenerated solid shell element is used to simulate box girders and material nonlinearity is considered. Since pre-stressed concrete box girders usually have a large number of curve prestressed tendons, a type of combined element is presented to simulate the prestressed tendons of box girders, and then the number of elements can be significantly reduced. The analytical results are compared with full-scale failure test results. The comparison shows that the presented method can be effectively applied to the failure analysis of in-situ continuous prestressed concrete box girders, and it also shows that the studied old bridge still has enough load carrying capacity. 展开更多
关键词 full-scale failure test prestressed concrete box girder finite element analysis combined element prestressed tendon load carrying capacity
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Damage and failure rule of rock undergoing uniaxial compressive load and dynamic load 被引量:19
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作者 左宇军 李夕兵 +3 位作者 周子龙 马春德 张义平 王卫华 《Journal of Central South University of Technology》 EI 2005年第6期742-748,共7页
For understanding the damage and failure rule of rock under different uniaxial compressive loads and dynamic loads, tests on red sandstone were carried out on Instron 1342 electro-servo controlled testing system with ... For understanding the damage and failure rule of rock under different uniaxial compressive loads and dynamic loads, tests on red sandstone were carried out on Instron 1342 electro-servo controlled testing system with different uniaxial compressive loads of 0, 2, 4 and 6 MPa. It is found that peak stress, peak strain, elastic modulus and total strain energy decrease with the increase of static compressive stress. Based on the test results, the mechanism on damage and failure of rock was analyzed, and according to the equivalent strain hypothesis, a new constitutive model of elastic-plastic damage was established, and then the calculated results with the established model were compared with test results to show a good agreement. Furthermore the rule of releasing ratio of damage strain energy was discussed. 展开更多
关键词 uniaxial static compressive load dynamic load DAMAGE constitutive model ENERGY
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Power System Simulation Laboratory of EPRI of China
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作者 曾昭华 蒋卫平 《Electricity》 2001年第4期25-29,共5页
The Power System Simulation Lab constructed specifically for the Three Gorges AC/DC hybrid transmissionstudy is equipped mainly with a real-time power system simulator, which can jointly operate with existing TNA andH... The Power System Simulation Lab constructed specifically for the Three Gorges AC/DC hybrid transmissionstudy is equipped mainly with a real-time power system simulator, which can jointly operate with existing TNA andHVDC Simulator respectively. Appraised by the State Power Corporation 3 years ago, this Lab was proved reachinginternational advanced level. Several large-scaled power system studies, such as the "Simplified Three Gorges PowerSystem Study" have achieved good results.[ 展开更多
关键词 power system hybrid real-time simulator
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xperimental Study of Heat Transfer Enhancement and Friction Loss Induced by Inserted Rotor-assembled Strand (I) Water 被引量:4
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作者 谢鹏程 李锋祥 +3 位作者 丁玉梅 阎华 关昌峰 杨卫民 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第6期849-855,共7页
The single-phase pressure drop and heat transfer in a rotor-assembled strand inserted tube were measured using water as the working fluid.Experiment using a smooth tube was carried out to calibrate the experimental sy... The single-phase pressure drop and heat transfer in a rotor-assembled strand inserted tube were measured using water as the working fluid.Experiment using a smooth tube was carried out to calibrate the experimental system and the data reduction method.In the experiment,fixed mounts were used to eliminate the entrance effect. The experimental results of smooth tube show that employment of fixed mounts leads to a visible bias of friction factor at relative low Reynolds numbers,although it does not significantly affect the Nusselt numbers.The measured data of inserted tube reveal that rotor-assembled strand can significantly improve heat transfer with the Nusselt number increased by 101.6%-106.6%and the overall heat transfer coefficient increased by 58.1%-67.4%within the Reynolds number range of 20000 to 36000.Meanwhile,friction factor increases by 52.2%-84.2%within the same Reynolds number range.The correlations of Nusselt number and friction factor as function of the Reynolds number and Prandtl number were determined through multivariant linear normal regression. 展开更多
关键词 heat transfer enhancement rotor-assembled strand friction factor DEPENDENCY
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Entrustable professional activities in nursing:A concept analysis 被引量:6
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作者 Modi Al-Moteri 《International Journal of Nursing Sciences》 CSCD 2020年第3期277-284,共8页
Objective:Entrustable professional activities(EPAs)is a newly emerging concept.This paper aims at analyzing the concept of"EPAs"to clarify the meaning and to identify its components for optimum understanding... Objective:Entrustable professional activities(EPAs)is a newly emerging concept.This paper aims at analyzing the concept of"EPAs"to clarify the meaning and to identify its components for optimum understanding of the concept for use in nursing education and future research.Method:Three databases-ProQuest,Ovid,and PubMed-were retrieved,and Walker and Avant's concept analysis approach was used to analyze the concept of EPAs.Results:Based on the analysis,three attributes of EPAs were defined,namely (1)EPAs should be restricted to a limited number of tasks;(2)reflect the experience curve;and (3)include acceptance of responsibility and accountability.The antecedent of EPAs is a holistic and integrated assessment approach.This will eventually lead to anticipated consequences such as a mastery of core competencies and an increase in the level of autonomy.Conclusion:The study may contribute to a reduction in the ambiguity of this concept to better apply it in nursing practice. 展开更多
关键词 ASSESSMENT Clinical training COMPETENCY Entrustable professional activities Nursing education
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