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病人健康宣教三步法 被引量:10
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作者 方燕燕 《安徽卫生职业技术学院学报》 2007年第6期103-104,共2页
目的:探讨住院病人不同时期的宣教特点;方法:根据住院病人住院期间的不同时期,通过健康宣教三步法进行健康宣教;结果:通过三步法能够增强宣教的效果;结论:健康宣教在病人住院的不同时期应具有其特异性。
关键词 住院病人 健康宣教 三步法
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Adaptive optimization of agile organization of command and control resource 被引量:8
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作者 Yang Chunhui Liu Junxian +1 位作者 Chen Honghui Luo Xueshan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第3期558-564,共7页
Adaptive optimization is one of the means that agile organization of command and control resource (AOC2R) adapts for the dynamic battlefield environment. A math model of the adaptive optimization of AOC2R is put for... Adaptive optimization is one of the means that agile organization of command and control resource (AOC2R) adapts for the dynamic battlefield environment. A math model of the adaptive optimization of AOC2R is put forward by analyzing the interrelating concept and research. The model takes the adaptive process as a multi-stage decision making problem. The 2-phases method is presented to calculate the model, which obtains the related parameters by running the colored Petri net (CPN) model of AOC2R and then searches for the result by ant colony optimization (ACO) algorithm integrated with genetic optimization techniques. The simulation results demonstrate that the proposed algorithm greatly improves the performance of AOC2R. 展开更多
关键词 command and control organization adaptive optimization of organization dynamic-window-search ant colony optimization 3-phase organizational design.
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强震下单层球面网壳连续倒塌机理 被引量:5
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作者 张毅刚 周海涛 吴金志 《北京工业大学学报》 CAS CSCD 北大核心 2013年第4期562-569,共8页
以单层凯威特球面网壳连续倒塌全过程非线性仿真计算为例,通过对地震过程中结构构件变形、受力、损伤等参量发展特征的研究分析,提出单层球面网壳连续倒塌过程可分为3个阶段,阐述了结构连续倒塌全过程的机理.分析不同地震峰值加速度条... 以单层凯威特球面网壳连续倒塌全过程非线性仿真计算为例,通过对地震过程中结构构件变形、受力、损伤等参量发展特征的研究分析,提出单层球面网壳连续倒塌过程可分为3个阶段,阐述了结构连续倒塌全过程的机理.分析不同地震峰值加速度条件下这3个阶段中结构重心竖向位移的变化特征,在此基础上,提出了适用于单层球面网壳结构的性态水平描述,并建立基于结构重心竖向相对位移的损伤评估指数.这些工作对于空间结构强震下灾变机理的进一步研究有较好的参考意义. 展开更多
关键词 单层球面网壳 强震 连续倒塌机理 三阶段 性态水平描述 损伤评估
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A new level set model for cell image segmentation 被引量:4
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作者 马竟锋 侯凯 +1 位作者 包尚联 陈纯 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第2期568-574,共7页
In this paper we first determine three phases of cell images: background, cytoplasm and nucleolus according to the general physical characteristics of cell images, and then develop a variational model, based on these... In this paper we first determine three phases of cell images: background, cytoplasm and nucleolus according to the general physical characteristics of cell images, and then develop a variational model, based on these characteristics, to segment nucleolus and cytoplasm from their relatively complicated backgrounds. In the meantime, the preprocessing obtained information of cell images using the OTSU algorithm is used to initialize the level set function in the model, which can speed up the segmentation and present satisfactory results in cell image processing. 展开更多
关键词 cell image segmentation 3-phase level set OTSU algorithm
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三相四线并联型有源电力滤波器的MATLAB/SIMULINK仿真 被引量:3
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作者 向东 戴珂 +1 位作者 魏学良 谢斌 《电气技术》 2006年第8期20-23,共4页
有源电力滤波器的数学模型是分析和研究有源电力滤波器的基础,同时数学模型还为计算机仿真提供了理论依据。本文以带电容中点的三相PWM变换器为研究对象,对并联型电力有源滤波器建立了数学模型,在此基础上,对整个系统控制策略进行了详... 有源电力滤波器的数学模型是分析和研究有源电力滤波器的基础,同时数学模型还为计算机仿真提供了理论依据。本文以带电容中点的三相PWM变换器为研究对象,对并联型电力有源滤波器建立了数学模型,在此基础上,对整个系统控制策略进行了详细地研究,提出了在d-q-0坐标下的直接电流控制方法,并通过仿真证明了该数学模型的正确性和控制策略的有效性。 展开更多
关键词 三相四线有源电力滤波器 数学模型 d-q-0控制 MATLAB\SIMULINK仿真
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直流无刷电机驱动芯片LB11820M的原理及应用 被引量:2
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作者 栗桂凤 《国外电子元器件》 2004年第10期35-38,共4页
LB11820M是日本SANYO(三洋)公司开发的三相直流无刷电机驱动芯片。它具备开环三相电机控制所需的全部有效功能 ,并且具有比较完善的保护电路。文中介绍了LB11820M的特点、功能和工作原理 ,给出了其典型应用电路。
关键词 LB11820M 三相 无刷电机 控制
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Modeling and Simulation of Two-Staged Separation Process for an Onshore Early Production Facility
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作者 Ojo Ademola J. G. Akpa K. K. Dagde 《Advances in Chemical Engineering and Science》 2019年第2期127-142,共16页
Early Production Facilities are makeshift process deployment that ensures that marginal oilfield operators make revenues from their new discoveries with little cash outlay and limited investment risks. Authors have in... Early Production Facilities are makeshift process deployment that ensures that marginal oilfield operators make revenues from their new discoveries with little cash outlay and limited investment risks. Authors have in past simulated a gas process facility using Hysys without particularly developing mathematical models for the key equipment. There also has been modeling of phase separation dynamics and process simulation but still without models for equipment. We basically developed models for the critical process equipment for early production, sized the equipment with data from a marginal field in the Niger delta region of Nigeria and then ran a dynamic simulation with the sized equipment. The important elements of the deployment are two-phase process vessel, 3-phase process vessel;knock-out drum, produced water treatment unit. Mathematical models were developed and adapted with Mathlab for the equipment sizing whilst ASPEN PLUS was used for simulating the process. Process data retrieved from a marginal field in Nigeria was used as input to quantify the equipment models. Sized equipment was deployed in Hysys V8.8 for a steady and dynamic state. The system simulation was comprised of a two-phase process vessel followed by a 3-phase process vessel [1]. The unwanted gas was sent to knock out drum for removal of entrained liquid droplets before flaring (this was because the volume of gas processed is deemed uneconomical) and produced water to treatment unit for removing droplets of oil before disposal. Gas, oil and water were fed into the first stage separator (2-phase) at 132918.34 Ibmole/hr, 7622.95 Ibmole/hr and 1082.74 Ibmole/hr respectively. The operating pressures of the first and second vessels were at 850 psi and 150 psi respectively. The 2-phase vessel flashed off 96.7% of the gas and increased the liquid recovery by 3.3%. At the end of the second stage separation, oil yield increased by 270 Ibmole/hr, the gas increased by 110.15 Ibmole/hr whilst water reduced by 379 Ibmole/hr. This result confirmed that th 展开更多
关键词 Modeling and Simulation 2-phase PROCESS VESSEL 3-phase PROCESS VESSEL Effective LENGTH Seam-Seam LENGTH SLENDERNESS Ratio
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Characterization of a 3-Phase a.c. Free Burning Arc Plasma 被引量:1
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作者 夏维东 Laurent FULCHERI +2 位作者 Jose GONZALEZ-AGUILAR 李辉 Thomas M. GRUENBERGER 《Plasma Science and Technology》 SCIE EI CAS CSCD 2006年第2期156-163,共8页
A 3-phase a.c. arc plasma reactor with large volume plasma has been developed for the synthesis of new carbon nano-structures. One of the main characteristics of the plasma system is related to the absence of a fixed ... A 3-phase a.c. arc plasma reactor with large volume plasma has been developed for the synthesis of new carbon nano-structures. One of the main characteristics of the plasma system is related to the absence of a fixed neutral point. This gives rise to a rich and complex phenomenology related to instabilities and arc motion since the arcs are "burning" freely in the gas flow between the three electrodes. This paper is dedicated to the analysis of the behavior of such a system under typical conditions using argon and nitrogen as plasma gases. A classification of are configuration, arc commutating, arc interaction, arc motion and arc instabilities are discussed based on ultra high-speed cine camera analysis. A simple model describing the time evolution of the system is also presented and compared with the experimental measurements. The results show that an adequate control could allow the improvement of the overall system. 展开更多
关键词 3-phase AC arc plasma free arc arc motion arc commutating arc instabilities
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A new design of stator magnetic system for 3-phase & 12-pole HB stepper
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作者 任雷 史敬灼 王宗培 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1999年第3期52-56,共5页
A new design of stato magnetic System is Proposed for 3-phase & 12-pole HB stepper, and it features bet-ter distribution of magntic lield to incare Pullou tope and bopmve Operaonal stability of moor and minimummut... A new design of stato magnetic System is Proposed for 3-phase & 12-pole HB stepper, and it features bet-ter distribution of magntic lield to incare Pullou tope and bopmve Operaonal stability of moor and minimummutual inductance between phase windimp to make design of control circuit easier, and application proved it is as good as expected. 展开更多
关键词 HB STEPPER STATOR MAGNETIC system 3-phase STEPPER
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Simulation and reliability analysis of shunt active power filter based on instantaneous reactive power theory 被引量:1
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作者 CUI Yu-long LIU Hong +1 位作者 WANG Jing-qin SUN Shu-guang 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第3期416-421,共6页
This paper first discusses the operating principle of instantaneous reactive power theory. Then, the theory is introduced into shunt active power filter and its control scheme is studied. Finally, Matlab/Simulink powe... This paper first discusses the operating principle of instantaneous reactive power theory. Then, the theory is introduced into shunt active power filter and its control scheme is studied. Finally, Matlab/Simulink power system toolbox is used to simulate the system. In the simulation model, as the most common harmonic source, 3-phase thyristor bridge rectifier circuit is constructed. The simulation results before and after the shunt active filter was switched to the system corresponding to different firing angles of the thyristors are presented and analyzed, which demonstrate the practicability and reliability of the proposed shunt active filter scheme. 展开更多
关键词 Shunt active filter Instantaneous reactive power theory HARMONIC 3-phase thyristor bridge rectifier Matlab/ Simulink
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三相异步电动机常见发热故障及处理方法 被引量:1
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作者 陈娟 《安徽电子信息职业技术学院学报》 2003年第4期69-70,73,共3页
文章以三相异步电动机为研究对象,从多方面叙述了三相异步电动机的常见发热故障和处理方法。
关键词 三相异步电动机 发热故障 处理方法 电源 负载
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3-Phase Modeling for the Origin of Chinese Lithium-Rich Brines
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作者 HUANG Wenbin WU Xishun +1 位作者 DU Xiaohui LI Li 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期339-340,共2页
There are significantly different origins and mineralizations among various lithium-rich brines of the world.As for Clayton Valley,Nevada,the data and interpretations recently presented suggest that the model
关键词 3-phase modeling lithium brine origin Qaidam Basin
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Elimination of Partial Overloading of Generators Under Unbalanced Operating Conditions of Power Systems
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作者 Sudhakar Reddy Sama Subrata Paul Sunita Halder Nee Dey 《CSEE Journal of Power and Energy Systems》 SCIE 2016年第1期81-87,共7页
Unbalanced operating condition in a power system can cause partial overloading of the generators in the network,a condition where one or two of the three phases of the generator become overloaded even if the total 3-p... Unbalanced operating condition in a power system can cause partial overloading of the generators in the network,a condition where one or two of the three phases of the generator become overloaded even if the total 3-phase power output of the generator is within its specified limit.Partial overloading of generators beyond certain limits is undesirable and must be avoided.Distribution systems are often subjected to highly unbalanced operating conditions.Introduction of distributed generations(DGs),therefore,has rendered today’s distribution systems quite susceptible to this problem.Mitigation of this problem requires the issue to be addressed properly during analysis,operation and planning of such systems.Analysis,operation and planning of power networks under unbalanced operating condition require 3-phase load flow study.The existing methods of 3-phase load flow are not equipped to take into account any limit on the loadings of the individual phases of the generators.In the present work,a methodology based on NewtonRaphson(N-R)3-phase load flow with necessary modifications is proposed.The proposed methodology is able to determine the safe loading limits of the generators,and,can be adopted for operation and planning of power networks under unbalanced operating conditions to overcome the above difficulties.Test results on IEEE-37 bus feeder network are presented to demonstrate the effectiveness of the proposed method. 展开更多
关键词 Newton Raphson 3-phase load flow partial overloading of generators unbalanced operating condition of power systems
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民用建筑三相配电中性线电流的确定
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作者 项彬 《湖北汽车工业学院学报》 1997年第4期61-65,共5页
本文引入相量负载系数β_k(k=1,2,3)来描述电路中三相负载的动态变化,通过对常见的三相四线电路的分析,从理论上获得了中性线电流上限值的计算公式。文中的分析方法和结论对配电设计有一定的参考价值。
关键词 相量 三相载 相量负载系数 负载导纳 中性线 动态变化 三相四线电路 民用建筑
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Fault diagnosis algorithm for 3-phase passive rectifiers based on frequency-domain analysis for acceleration grid power supply in CFETR NBI system
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作者 Bangyou ZHU Shaoxiang MA +3 位作者 Hongqi ZHANG Zhiheng LI Ming ZHANG Yuan PAN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第12期40-54,共15页
The acceleration grid power supply(AGPS) is a crucial part of the Negative-ion Neutral Beam Injection system in the China Fusion Engineering Test Reactor,which includes a 3-phase passive(diode) rectifier.To diagnose a... The acceleration grid power supply(AGPS) is a crucial part of the Negative-ion Neutral Beam Injection system in the China Fusion Engineering Test Reactor,which includes a 3-phase passive(diode) rectifier.To diagnose and localize faults in the rectifier,this paper proposes a frequencydomain analysis-based fault diagnosis algorithm for the rectifier in AGPS.First,time-domain expressions and spectral characteristics of the output voltage of the TPTL-NPC inverter-based power supply are analyzed.Then,frequency-domain analysis-based fault diagnosis and frequency-domain analysis-based sub-fault diagnosis algorithms are proposed to diagnose open circuit(OC) faults of diode(s),which benefit from the analysis of harmonics magnitude and phase-angle of the output voltage.Only a fundamental period is needed to diagnose and localize exact faults,and a strong Variable-duration Fault Detection Method is proposed to identify acceptable ripple from OC faults.Detailed simulations and experimental results demonstrate the effectiveness,quickness,and robustness of the proposed algorithms,and the diagnosis algorithms proposed in this article provide a significant method for the fault diagnosis of other rectifiers and converters. 展开更多
关键词 fault diagnosis 3-phase passive rectifier acceleration grid power supply(AGPS) fault localization
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A Device for Measuring 3-Phase Alternating Current at a Distance
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作者 Seppo Makinen 《Journal of Electromagnetic Analysis and Applications》 2015年第8期209-216,共8页
We have made a preliminary study on a possibility to build a device, which could measure three-phase alternating current at a distance. This report gives a brief look at the theoretical background related with such a ... We have made a preliminary study on a possibility to build a device, which could measure three-phase alternating current at a distance. This report gives a brief look at the theoretical background related with such a device and derives several mathematical results associated with the theory and the structure of the device. Our results suggest that such a device can be built, assuming the distances between the three current-carrying wires and the two sensors of the device are known accurately enough. There are ways to measure these distances, but this article does not concentrate on them. 展开更多
关键词 Electromagnetic Induction 3-phase Alternating Current AMMETER
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Al-Ti-B晶粒细化合金中的有效形核相 被引量:46
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作者 孝云祯 马宏声 +1 位作者 路贵民 刘劲波 《中国有色金属学报》 EI CAS CSCD 北大核心 1997年第3期137-139,共3页
研究了AlTiB晶粒细化合金中各化合物相TiAl3、TiB2和AlB2对铝晶粒的细化作用。结果表明,TiAl3相是有效形核相,TiB2和AlB2相不能单独作为形核相,B对AlTiB的细化作用有显著影响,但B及... 研究了AlTiB晶粒细化合金中各化合物相TiAl3、TiB2和AlB2对铝晶粒的细化作用。结果表明,TiAl3相是有效形核相,TiB2和AlB2相不能单独作为形核相,B对AlTiB的细化作用有显著影响,但B及硼化物不能单独影响细化过程,而是富集在TiAl3相中对细化过程产生重要影响。 展开更多
关键词 晶粒细化 TiAl3 有效形核相 铝合金 中间合金
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探月三期月地高速再入返回飞行器技术设计与实现 被引量:50
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作者 杨孟飞 张高 +6 位作者 张伍 彭兢 王勇 王晓磊 陈春亮 杜颖 张正峰 《中国科学:技术科学》 EI CSCD 北大核心 2015年第2期111-123,共13页
探月三期月地高速再入返回任务是我国首个深空探测再入返回任务,研制目的是突破和掌握月地高速再入返回关键技术,为嫦娥五号任务研制奠定基础.本文给出了月地高速再入返回飞行器的任务特点,进行了任务概貌和研制过程介绍,阐述了双平台... 探月三期月地高速再入返回任务是我国首个深空探测再入返回任务,研制目的是突破和掌握月地高速再入返回关键技术,为嫦娥五号任务研制奠定基础.本文给出了月地高速再入返回飞行器的任务特点,进行了任务概貌和研制过程介绍,阐述了双平台和多目标飞行器方案设计及飞行过程设计情况,并给出了在轨飞行结果.结果表明,月地高速再入返回飞行器所有功能性能均满足任务要求,在轨飞行状态正常,技术设计正确可行. 展开更多
关键词 探月三期 月地返回 高速再入 双平台
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新型三维空间矢量脉宽调制在三相四线系统中的应用 被引量:25
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作者 戴宁怡 黄民聪 +1 位作者 唐净 韩英铎 《电力系统自动化》 EI CSCD 北大核心 2003年第17期45-49,共5页
提出了一种应用于三相四线系统的三维空间矢量脉宽调制 (3DSVPWM)方法。介绍了三维空间中电压矢量的分布以及空间矢量脉宽调制的实现方法。与以往基于二维算法的空间矢量脉宽调制不同 ,在三维空间矢量调制中 ,有 8个不同的空间电压矢量... 提出了一种应用于三相四线系统的三维空间矢量脉宽调制 (3DSVPWM)方法。介绍了三维空间中电压矢量的分布以及空间矢量脉宽调制的实现方法。与以往基于二维算法的空间矢量脉宽调制不同 ,在三维空间矢量调制中 ,有 8个不同的空间电压矢量对应于 8组开关模式 ;零矢量的作用也不再局限于减小开关损耗、优化开关序列 ,还可以用来补偿中线电流。这种新型的空间矢量脉宽调制方法被用在三相四线系统中的并联电能质量补偿设备中 ,用来控制一个三桥臂逆变器 ,实现对电流谐波和中线电流的补偿。文中给出了仿真实验的结果 ,并与传统滞环控制方法的实验结果进行了比较 ,验证了该方法的正确性 。 展开更多
关键词 逆变器 三维空间矢量脉宽调制 三相四线系统 电能质量补偿
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12/3相双绕组感应发电机的谐波不对称分析 被引量:24
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作者 王东 马伟明 +2 位作者 顾伟峰 肖飞 张波涛 《中国电机工程学报》 EI CSCD 北大核心 2004年第5期148-152,共5页
励磁调节器所引入的谐波电流会引起12相功率绕组的不对称工作。为了研究谐波不对称的产生机理,该文在建立基于基波的12/3相双绕组感应电机dq0模型的基础上,通过对两套绕组间的谐波耦合分析,经过简化,得出了可用于谐波分析的等效电路模... 励磁调节器所引入的谐波电流会引起12相功率绕组的不对称工作。为了研究谐波不对称的产生机理,该文在建立基于基波的12/3相双绕组感应电机dq0模型的基础上,通过对两套绕组间的谐波耦合分析,经过简化,得出了可用于谐波分析的等效电路模型。从中得到了规律性的认识,为该类电机的设计和推广起到了促进作用。试验与理论分析结果的对比说明了所建模型和分析方法的正确性。 展开更多
关键词 感应发电机 谐波 励磁调节器 等效电路 12/3相双绕组
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