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无结锚钉与空心钉固定后交叉韧带胫骨撕脱骨折

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中国矫形外科杂志 2024年第16期32卷 1461-1466页

作者：彭俊洋张云鹏陈晖魏俊成田纪伟南京医科大学附属明基医院骨科江苏南京210019

[目的]比较关节镜下无结锚钉与空心钉固定技术治疗后交叉韧带(posterior cruciate ligament,PCL)胫骨止点撕脱骨折疗效。[方法]回顾性分析2013年10月—2020年10月本院收治的急性PCL胫骨止点撕脱性骨折28例患者的临床资料,均实施关节镜... 详细信息

[目的]比较关节镜下无结锚钉与空心钉固定技术治疗后交叉韧带(posterior cruciate ligament,PCL)胫骨止点撕脱骨折疗效。[方法]回顾性分析2013年10月—2020年10月本院收治的急性PCL胫骨止点撕脱性骨折28例患者的临床资料,均实施关节镜下复位固定手术。根据医患沟通结果,14例患者采用锚钉固定,另外14例采用空心钉固定。比较两组围手术期、随访和影像资料。[结果]所有患者均顺利完成手术,无严重并发症。两组在手术时间、手术切口大小、失血量、切口愈合等级和住院时间的差异均无统计学意义(P>0.05)。锚钉组在术中透视[(0)次vs(2.1±0.4)次,P0.05)。与术后3个月相比,末次随访时两组患者VAS、IKDC、Lysholm评分和ROM均显著改善(P0.05)。影像方面,两组间骨折复位质量和骨折愈合时间的差异均无统计学意义(P>0.05)。至末次随访时,两组患者均无明显膝关节退变加重的影像改变。[结论]无结锚钉与空心钉固定技术治疗PCL胫骨止点撕脱骨折均可获得良好的手术效果。相比之下,无结锚钉术后舒适度高,但治疗费用更高。

关键词：后交叉韧带胫骨止点撕脱骨折关节镜术无结锚钉空心钉

Effects of Magnetic Shear on Current Penetration in a Tokamak

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Chinese Physics Letters 2001年第6期18卷 802-804页

作者： zhang peng-yun WANG Long Institute of Physics Chinese Academy of SciencesBeijing 100080

The penetrations of the parallel and perpendicular components of plasma currents are interrelated to each other due to the existence of magnetic shear in a tokamak *** of the shear on the penetration of Fourier components of toroidal plasma current are analysed in a cylindrical column *** current penetration is obviously strengthened by the shear for a bell-like conductivity profile and low safety factor and low aspect ratio.

关键词： tokamak strengthened cylindrical

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直接前入路全髋关节置换的学习曲线

中国矫形外科杂志 2024年第1期32卷 80-83页

作者：肖守允沈思远梁锋田纪伟张云鹏丁惠民南京医科大学附属明基医院骨科江苏南京210019

[目的]分析直接前入路(direct anterior approach,DAA)全髋关节置换术(total hip arthroplasty,THA)治疗股骨颈骨折的临床疗效,并探讨其学习曲线。[方法]回顾性分析2020年1月—2021年12月在本院骨科采用用DAA入路行THA58例股骨颈骨折患... 详细信息

[目的]分析直接前入路(direct anterior approach,DAA)全髋关节置换术(total hip arthroplasty,THA)治疗股骨颈骨折的临床疗效,并探讨其学习曲线。[方法]回顾性分析2020年1月—2021年12月在本院骨科采用用DAA入路行THA58例股骨颈骨折患者,采用累积和分析法分析学习曲线,比较不同学习阶段患者临床资料。[结果]依据CUSUM学习曲线,初始期为编序1~22病例,成长期为编序23~32病例,成熟期为编序33~58病例。随手术例数的积累,手术时间[(165.1±16.5)min,(139.8±7.2)min,(120.4±8.2)min,P0.05)。[结论]股骨颈骨折DAA-THA具有术中损伤小,恢复快等优势,但其有较长学习曲线,需经过23~32例才能达到技术成熟期。

关键词：股骨颈骨折全髋关节置换术直接前入路学习曲线累积和分析法

Stable Flocking of Multiple Agents Based on Molecular Potential Field and Distributed Receding Horizon Control

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Chinese Physics Letters 2011年第4期28卷 47-50页

作者： zhang yun-peng DUAN Hai-Bin zhang Xiang-Yin State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijing 100191 Science and Technology on Aircraft Control Laboratory Beihang UniversityBeijing 100191

A novel distributed control scheme to generate stable flocking motion for a group of agents is *** this control scheme,a molecular potential field model is applied as the potential field function because of its smoothness and unique *** approach of distributed receding horizon control is adopted to drive each agent to find its optimal control input to lower its potential at every *** results show that this proposed control scheme can ensure that all agents eventually converge to a stable flocking formation with a common velocity and the collisions can also be avoided at the same time.

关键词： Agents agent scheme

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喷涂角度对螺栓表面涂层厚度均匀性的影响

科学技术与工程 2024年第6期24卷 2362-2366页

作者：张云鹏万冰华赵彦伟马睿张涛卢文壮南京航空航天大学机电学院南京210016 天津市紧固连接技术企业重点实验室天津300300 航天精工股份有限公司天津300300 空军装备部驻北京地区军事代表局驻天津地区第二军事代表室天津300300

针对工程中采用铝涂料涂覆螺栓时螺栓表面铝涂层易出现的厚度不均匀问题,研究喷涂角度对螺栓表面涂层均匀性的影响规律。对喷涂系统的喷嘴和螺栓进行建模,通过计算流体动力学仿真软件Fluent建立了雾化流场的气液两相流物理模型,使用离... 详细信息

针对工程中采用铝涂料涂覆螺栓时螺栓表面铝涂层易出现的厚度不均匀问题,研究喷涂角度对螺栓表面涂层均匀性的影响规律。对喷涂系统的喷嘴和螺栓进行建模,通过计算流体动力学仿真软件Fluent建立了雾化流场的气液两相流物理模型,使用离散相模型(discrete phase model, DPM)分析了流场中气相和液相的相互作用,获得了在不同角度下的喷涂流场,预测了螺栓表面液膜沉积厚度。搭建了喷涂试验系统并与模拟结果进行了验证,模拟和试验研究均表明在喷涂角度为30°时螺栓表面涂层均匀性最佳。

关键词：喷涂流场铝涂层流体仿真厚度均匀性

Optimized Selection Method of Air Combat Course of Action under Stochastic Uncertainty

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Journal of Systems Science and Systems Engineering 2024年第4期33卷 494-518页

作者： yun Zhong Jieyong zhang peng Sun Lujun Wan Kepeng Wang Information and Navigation College Air Force Engineering UniversityXi’an710077China Equipment Management and Unmanned Aerial Vehicle Engineering College Air Force Engineering UniversityXi’an710051China Air Traffic Control and Navigation College Air Force Engineering UniversityXi’an710051China Unit 94040 of PLA Korla841000China

Aiming at the design problem of aviation swarm combat course of action(COA),considering the influence of stochastic parameters in the causal relationship model and optimization problem model,according to the dynamic influence net(DIN)theory,stochastic simulation technique,feedforward neural network(FNN)function approximation technique and multi-objective artificial fish school algorithm(MOAFSA),this paper proposed a COA optimized method based on DIN and multi-objective stochastic chance constraint optimization for aviation swarm ***,on the basis of establishing the overall framework of the model and defining the elements of causal relationship modeling,the static and dynamic causal relationship modeling and optimization problem modeling were carried out ***,the probability propagation mechanism of DIN was established,which mainly included two aspects,i.e.,the overall process and the specific ***,input and output data were generated based on stochastic *** to these data,FNN was adopted for function approximation,and MOAFSA was adopted for iterative ***,the rationality of the model,and the effectiveness and superiority of the algorithm were verified through multiple sets of simulation cases.

关键词： Stochastic uncertainty aviation swarm stochastic simulation course of action feedforward neural network multi-objective artificial fish school algorithm

Risk Assessment for Hybrid AC/DC Systems Based on Transient Energy Function

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1654-1663页

作者： peng Sun yun Teng Mingli zhang Zhe Chen Shenyang University of Technology Shenyang 110870China Liaoning Electric Power Co.Ltd.Economic Research Institute Shenyang 110000China Department of Energy Technology Aalborg UniversityAalborgDK DK 9220

In order to accurately assess the risk of the hybrid AC/DC network under fault,a risk assessment method for the hybrid AC/DC system based on the transient energy function is ***,based on the energy transfer relationship of the hybrid AC/DC power system,the transient energy function model of the hybrid AC/DC system is *** on the operating data of the power grid,the energy function is used as an efficiency variable,and the efficiency variable is integrated into the prior risk probability calculation of nodes in the network,and a Bayesian network-based risk assessment model of hybrid AC/DC system is *** the dynamic update model of network cascading failures,the clique tree propagation algorithm is used to dynamically calculate the posterior risk probability of the node to realize the dynamic assessment of the network ***,the improved IEEE-39 node hybrid AC/DC system is used as an example for *** results show that the proposed model can not only effectively evaluate the overall safety of the network,but also has feasibility in predicting faults,which can provide a theoretical basis for the stability control of the hybrid AC/DC system.

关键词： Cascading failure energy function hybrid AC-DC system risk assessment

Dust Particle Density and Charges in Radio-Frequency Mixture Discharge Plasma

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Chinese Physics Letters 2011年第9期28卷 186-189页

作者： WU Jing zhang peng-yun SUN Ji-Zhong YAO Lie-Ming DUAN Xu-Ru School of Physical Electronics University of Electronic Science and Technology of ChinaChengdu 610054 Center for Fusion Science Southwestern Institute of PhysicsChengdu 610054 School of Physics and Optoelectronic Technology Dalian University of TechnologyDalian 116024

We develop a method for measuring the density and charges of dust particles in a capacitive coupled cylinder discharge chamber in mixtures of gases SiH4/C2H4/*** particles are created in situ using these reactive mixtures in rf discharge.A Langmuir probe is employed for the measurement of important plasma parameters,such as electron density,electron temperature and ion *** density and charges of dust particles is then calculated based on the data of the measurement of these parameters and a known dust plasma sheath *** curves of dust particle density versus rf power and gas pressure are presented,respectively,under various experimental *** dust charges versus different experimental conditions are also evaluated and presented.

关键词： density charges mixtures

Analysis of mechanical strengths of extreme line casing joint considering geometric, material, and contact nonlinearities

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Petroleum Science 2024年第3期21卷 1992-2004页

作者： Ji-yun zhang Chi peng Jian-Hong Fu Quan Cao Yu Su Jian-yun Pang Zi-Qiang Yu Petroleum Engineering School Southwest Petroleum UniversityChengdu610500SichuanChina Engineering Technology Research Institute of CNPC Southwest Oil and Gas Field Company Chengdu610017SichuanChina

To address the challenges associated with difficult casing running,limited annular space,and poor cementing quality in the completion of ultra-deep wells,the extreme line casing offers an effective solution over conventional ***,due to its smaller size,the joint strength of extreme line casing is reduced,which may cause failure when running in the *** address this issue,this study focuses on the CST-ZTΦ139.7 mm×7.72 mm extreme line casing and employs the elastic-plastic mechanics to establish a comprehensive analysis of the casing joint,taking into account the influence of geometric and material nonlinearities.A finite element model is developed to analyze the forces and deformations of the extreme line casing joint under axial tension and external collapse *** model investigates the stress distribution of each thread tooth subjected to various tensile forces and external ***,the tensile strength and crushing strength of the extreme line casing joint are determined through both analytical and experimental *** findings reveal that,under axial tensile load,the bearing surface of each thread tooth experiences uneven stress,with relatively high equivalent stress at the root of each thread *** end thread teeth are valuable spots for *** is observed that the critical fracture axial load of thread decreases linearly with the increase of thread tooth *** external pressure,the circumferential stress is highest at the small end of the external thread,leading to yield *** tensile strength of the joint obtained from the finite element model exhibits a relative error of less than 7%compared to the analytical and experimental values,proving the reliability of the finite element *** tensile strength of the joint is 3091.9 k ***,in terms of anti-collapse capability,the joints demonstrate higher resistance to collapse compared to the casing body,which is consistent with the test resul

关键词： Extreme line casing Elastic-plastic mechanics Finite element analysis Tensile strength Collapse strength