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Slip rate and locking degree of Haiyuan fault zone,northeastern Qinghai-Xizang plateau,based on refined block model and GPS data
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作者 Yang Liu Yuxuan Qiu +2 位作者 Jialiang Liu Yu Zhang Caijun Xu 《Geodesy and Geodynamics》 2025年第5期536-545,共10页
As a major fault in the northeastern Qinghai-Xizang Plateau,the Haiyuan fault zone is important for understanding the regional deformation.Aiming at the differences in the slip rate and locking degree obtained from di... As a major fault in the northeastern Qinghai-Xizang Plateau,the Haiyuan fault zone is important for understanding the regional deformation.Aiming at the differences in the slip rate and locking degree obtained from different studies,this study constructs a refined block model(including Qilian,Alxa,Ordos,Xining,Haiyuan,and Lanzhou blocks)and uses the grid search and simulated annealing methods to invert GPS data for slip rate and locking degree of the Haiyuan fault zone.The results are as follows:(1)The sinistral slip rates in the western,middle,and eastern segments are 4.93-5.22 mm/a,1.52-4.94 mm/a,and 0.43-1.18 mm/a,decreasing eastward on the whole,while the compression rates are 0.45-1.26 mm/a,0.58-2.62 mm/a,and3.52-4.48 mm/a,increasing eastward on the whole.(2)The locking depth of the western segment increases from about 5 km to about 20 km eastward;the middle segment decreases and then increases eastward;the eastern segment concentrates at about 20 km(PHI is about 0.86).(3)The slip deficit is relatively higher in the Lenglongling,Jinqianghe,Maomaoshan,and Liupanshan faults(averaging about 3.42 mm/a,4.16 mm/a,4.23 mm/a,and 3.43 mm/a within 20 km).(4)The Qilian,Alxa,Xining,Lanzhou,and Haiyuan blocks rotate clockwise,while the Ordos block rotates counterclockwise.Additionally,by comparing different block models,the Haiyuan block should be considered independently.The Haiyuan fault zone adjusts surrounding block movements and uplifts Liupanshan mountain tectonically.The results can provide important references for understanding the regional earthquake risk and deformation mechanism. 展开更多
关键词 Haiyuan fault zone Block model locking degree Slip rate
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Laser Cooling Alkaline-earth Atoms for Optical Clock in Chinese Space Station
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作者 Guodong Zhao Jian Xia +19 位作者 Yun Liu Yongzhuang Zhou Chihua Zhou Feng Guo Wenhai Wang Dejing He Min Feng Ting Liang Jie Ren Qinfang Xu Junwei Meng Feng Gao Yong Shen Xiaotong Lu Benquan Lu Yebing Wang Xiaohua Hu Wei Tan Hongxin Zou Hong Chang 《Chinese Physics Letters》 2025年第6期63-69,共7页
This study presents an achievement of laser cooling of alkaline-earth atoms in the Chinese Space Station’s strontium(Sr)atomic space optical clock.The system’s core components,physical unit,optical unit,and electric... This study presents an achievement of laser cooling of alkaline-earth atoms in the Chinese Space Station’s strontium(Sr)atomic space optical clock.The system’s core components,physical unit,optical unit,and electrical unit,have a total volume of 306 L and a total mass of 163.8 kg.These compact and robust units can overcome mechanical vibrations and temperature fluctuations during space launch.The laser sources of the optical unit are composed of diode lasers,and the injection locking of slave lasers is automatically performed by a program.In the experiment,a blue magneto-optical trap of cold atoms was achieved,with the atom numbers estimated to be approximately(1.50±0.13)×10^(6) for 87Sr and(8.00±0.56)×10^(6) for 88Sr.This work establishes a foundation for atomic confinement and high-precision interrogation in space-based optical clocks and expands the frontiers of cold atom physics in microgravity. 展开更多
关键词 STRONTIUM diode lasersand laser cooling optical clock slave lasers alkaline earth atoms Chinese space station injection locking
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Generation and dynamics of special mode-locked pulses in an ultrafast Er-doped fiber laser with SMF-GIMF-SMF saturable absorber 被引量:1
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作者 LIN Yingjie ZENG Qiong +3 位作者 JI Yubo SONG Yufeng WANG Ke WANG Zhenhong 《Optoelectronics Letters》 2025年第5期265-270,共6页
In this paper, we have demonstrated an Er-doped ultrafast laser with a single mode fiber-gradient index multimode fiber-single mode fiber(SMF-GIMF-SMF, SMS) structure as saturable absorber(SA), which can generate not ... In this paper, we have demonstrated an Er-doped ultrafast laser with a single mode fiber-gradient index multimode fiber-single mode fiber(SMF-GIMF-SMF, SMS) structure as saturable absorber(SA), which can generate not only stable single-pulse state, but also special mode-locked pulses with the characteristics of high energy and noisy behaviors at proper pump power and cavity polarization state. In addition, we have deeply investigated the real-time spectral evolutions of the mode-locked pulses through the dispersive Fourier transformation(DFT) technique. It can be found that the pulse regime can actually consist of a lot of small noise pulses with randomly varying intensities. We believe that these results will further enrich the nonlinear dynamical processes in the ultrafast lasers. 展开更多
关键词 ultrafast laser ER doped fiber SMF GIMF SMF dispersive Fourier transformation saturable absorber sa mode locked pulses nonlinear dynamics saturable absorber
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Fast-Lock Low-Jitter PLL with a Simple Phase-Frequency Detector 被引量:3
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作者 陈莹梅 王志功 章丽 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第1期88-92,共5页
A fast-locking, low-jitter, phase-locked loop (PLL) with a simple phase-frequency detector is proposed. The phase-frequency detector is composed of only two XOR gates. It simultaneously achieves low jitter and short... A fast-locking, low-jitter, phase-locked loop (PLL) with a simple phase-frequency detector is proposed. The phase-frequency detector is composed of only two XOR gates. It simultaneously achieves low jitter and short locking time. The voltage-controlled oscillator within the PLL consists of four-stage ring oscillators which are coupled to each other and oscillate with the same frequency and a phase shift of 45. The PLL is fabricated in 0. 1Stem CMOS technology. The measured phase noise of the PLL output at 500kHz offset from the 5GHz center frequency is - 102.6dBc/Hz. The circuit exhibits a capture range of 280MHz and a low RMS jitter of 2.06ps. The power dissipation excluding the output buffers is only 21.6roW at a 1.8V supply. 展开更多
关键词 phase locked loop phase-frequency detector voltage-controlled oscillator JITTER locking time
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Transient Dynamic Research of Deployable and Lockable Mechanism for Multi-Wing Considering Multiple Factors
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作者 Guangqing Zhai Jianguo Tao +5 位作者 Hong Xiao Chen Yao Runchao Zhao Hongwei Guo Guang Yang Rongqiang Liu 《Chinese Journal of Mechanical Engineering》 2025年第4期483-503,共21页
The spatial constraints of aircraft have accelerated the development of multi-wing deployable mechanisms.These systems enable the rapid,sub-second deployment of multiple folding wings,which generate high-energy impact... The spatial constraints of aircraft have accelerated the development of multi-wing deployable mechanisms.These systems enable the rapid,sub-second deployment of multiple folding wings,which generate high-energy impacts upon locking-resulting in oscillations that can adversely affect aerodynamic performance.Despite their importance,the transient dynamic characteristics during deployment and locking remain insufficiently explored.This study presents an integrated dynamic model for a single-actuator,multi-wing deployable mechanism that accounts for joint clearances,component elasticity,and locking collisions.This model is used to analyze the influence of transient driving on the motion errors of multiple folding wings,the locking oscillation amplitude,and the complete stabilization time.Results indicate that as the driving force and transient deployment speed increase,all dynamic performance characteristics are notably affected.Specifically,raising the transient driving force from 3000 to 7000 N leads to a maximum increase of 60.8%in oscillation amplitude and 78.4%in stabilization time.By comparing the results of the prototype experiment with the theoretical model,it is found that the errors of the maximum locking oscillation amplitude and the complete stabilization time for the three groups of folding wings are all within the acceptable range,which verifies the theoretical model.These findings advance the theoretical understanding of transient deployment dynamics and locking oscillations in high-speed deployable mechanisms. 展开更多
关键词 Folding wing Transient mechanism Dynamic characteristics locking collision
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Synchronized dual-wavelength mode-locked laser in normal dispersion regime
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作者 Yangrui Shi Haojing Zhang +2 位作者 Yuxuan Ren Junsong Peng Heping Zeng 《Chinese Physics B》 2025年第9期228-232,共5页
Synchronized dual-wavelength mode-locked laser is investigated numerically and experimentally in the normal dispersion regime.A programmable optical processor is introduced to shape the spectral profile and adjust the... Synchronized dual-wavelength mode-locked laser is investigated numerically and experimentally in the normal dispersion regime.A programmable optical processor is introduced to shape the spectral profile and adjust the net dispersion,which is demonstrated be a convenient and reliable approach to generate dual-color solitons.The time-stretch dispersive Fourier transform and frequency-resolved optical grating techniques are utilized to measure the spectral and temporal characteristics of dual-color solitons,respectively.The numerical results are consistent with experimental results.This work may facilitate the development of filter-based mode-locked laser and the understanding of multi-wavelength soliton dynamics. 展开更多
关键词 fiber laser mode locking DUAL-WAVELENGTH
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Load and lock: An emerging class of therapeutics that influence macromolecular dissociation
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作者 Raymond J Deshaies 《四川生理科学杂志》 2025年第8期1707-1707,共1页
Biology is governed by macromolecular interactions,perturbation of which often lies at the heart of disease.Most therapeutic drugs,whether they are small molecules or biologics,exert their effects through impeding suc... Biology is governed by macromolecular interactions,perturbation of which often lies at the heart of disease.Most therapeutic drugs,whether they are small molecules or biologics,exert their effects through impeding such interactions,whether they are of an enzyme with its substrate or a ligand with its receptor.Conversely,a handful of approved drugs and a larger number of candidates in development have the opposite effect:They either activate or inhibit a biological output by stabilizing a preexisting complex through reducing the rate at which its components dissociate(koff). 展开更多
关键词 macromolecular dissociation therapeutic drugswhether LOAD macromolecular interactionsperturbation activate inhibit biological output therapeutic drugs small molecules lock
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Deltopectoral vs deltoid split approach for proximal humerus fractures treated with locking plate:Our experience
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作者 Calogero Cicio Gianfranco Longo +11 位作者 Vito Pavone Gianluca Testa Rocco Ortuso Giovanni C Salvo Marco Ganci Ignazio Prestianni Alessio Ferrara Antonio Kory Alessandro Pietropaolo Anna M Monachino Enrica R Cuffaro Giacomo Papotto 《World Journal of Orthopedics》 2025年第9期46-55,共10页
BACKGROUND Proximal humerus fractures(PHFs)are common,especially in the elderly,and optimal surgical management remains debated.This study compares clinical,functional,and radiographic outcomes of deltoid split(DS)vs ... BACKGROUND Proximal humerus fractures(PHFs)are common,especially in the elderly,and optimal surgical management remains debated.This study compares clinical,functional,and radiographic outcomes of deltoid split(DS)vs deltopectoral(DP)approaches in PHFs treated with locking plates.AIM To evaluate and compare the clinical,functional,and radiographic outcomes-as well as postoperative complication rates-associated with the DS vs the DP surgical approach in the open reduction and internal fixation(ORIF)of PHFs using locking plate constructs.METHODS A multicenter retrospective study of 120 patients undergoing ORIF for closed Neer type II-IV PHFs between January 2023 and December 2023.Patients were grouped by surgical approach[DS(n=70),DP(n=50)].Outcome measures included Numeric Rating Scale(NRS)for pain,Quick-Disabilities in Arm,Shoulder,and Hand questionnaire(QuickDASH),Constant-Murley score,Short Form Health Survey-12v2,and radiographic alignment.Complication rates were recorded.Statistical significance was defined as P<0.05.RESULTS Early outcomes favored the DS group:(1)Lower NRS(3.1 vs 5.9);(2)Higher Constant-Murley(68.2 vs 50.5);and(3)Better QuickDASH(25.4 vs 37.1).Complication rate was lower in the DS group(1.66%vs 5.81%).Radiographic outcomes were comparable.Long-term results were similar between groups.CONCLUSION While both approaches yield satisfactory long-term outcomes,the DS approach is associated with faster early recovery and fewer complications,supporting its use in selected cases. 展开更多
关键词 Proximal humerus fracture Deltoid split Deltopectoral locking plate Open reduction and internal fixation Functional outcome
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Ti_(3)C_(2)T_(x)-Based Stress Sensing Fiber Modulator for Dichromatic Mode-Locking
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作者 Jing Liu Bin Shen +3 位作者 Yu Wan Lu Wan Chao-Qing Dai Yue-Yue Wang 《Chinese Physics Letters》 2025年第9期50-61,共12页
Fiber optic sensing technology,with its low transmission loss,wide bandwidth,and broad dynamic range,offers significant advantages for high-sensitivity measurements.In this study,a multi-band soliton modulation system... Fiber optic sensing technology,with its low transmission loss,wide bandwidth,and broad dynamic range,offers significant advantages for high-sensitivity measurements.In this study,a multi-band soliton modulation system for stress sensing is proposed,utilizing Ti_(3)C_(2)T_(x)to generate ultrashort pulses.By applying stress to microfibers,dichromatic periodic multisoliton mode-locking at 1530 nm and 1555.2 nm is achieved.Vibrational mechanical stress further modulates cross-phase interactions between solitons,inducing higher-order bound solitons with small-amplitude oscillations.These dynamic processes reveal complex nonlinear optical behaviors and enhance sensing capabilities.Additionally,the feasibility of stable mode-locking of Ti_(3)C_(2)T_(x)in a 1µm multimode cavity is analyzed using the multimode nonlinear Schrodinger equation,and multisoliton states are experimentally demonstrated by integrating a 1µm narrow-linewidth ultrafast multimode laser with a stressed microfiber. 展开更多
关键词 ti c tx mechanical stress applying stress ultrashort pulsesby dichromatic mode locking nonlinear optical behaviors stress sensing ultrashort pulses
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SOLO分类评价建结构 LOCK解读策略搭支架——“小人物命运交响曲”整本书阅读任务群思维进阶
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作者 吴健勇 曾艳娟 《福建基础教育研究》 2025年第7期20-24,共5页
针对整本书阅读任务群教学中存在的缺乏思辨探究、思维进阶层级、关联支架的问题,以“小人物命运交响曲”为专题,围绕《骆驼祥子》《人鼠之间》《长安的荔枝》三部小说进行群书阅读教学实践。以SOLO分类评价理论为指导,设计交际语境下... 针对整本书阅读任务群教学中存在的缺乏思辨探究、思维进阶层级、关联支架的问题,以“小人物命运交响曲”为专题,围绕《骆驼祥子》《人鼠之间》《长安的荔枝》三部小说进行群书阅读教学实践。以SOLO分类评价理论为指导,设计交际语境下的读写融合大任务,依据“LOCK”小说解读策略设计学习支架,搭建从单点、多点、关联到抽象拓展的任务链,实现整本书阅读学习任务群思维的结构化进阶。 展开更多
关键词 SOLO分类理论 整本书阅读 学习任务群 思维进阶 lock阅读策略
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Locking Effect of the Inhomogeneous Tectonic Lenticular Rock Mass in the Internal Geological Structure of the Baige Landslides
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作者 Peng Cao Huiming Tang +3 位作者 Kun Fang Jianhui Deng Zongliang Li Xinming Wu 《Journal of Earth Science》 2025年第4期1663-1681,共19页
In 2018,Baige,Xizang,witnessed two consecutive large-scale landslides,causing significant damage and drawing widespread attention.From March 2011 to February 2018,the Baige landslide exhibited a 50-m displacement with... In 2018,Baige,Xizang,witnessed two consecutive large-scale landslides,causing significant damage and drawing widespread attention.From March 2011 to February 2018,the Baige landslide exhibited a 50-m displacement without complete failure,culminating in a collapse in October 2018.The mechanisms behind its resistance to failure despite substantial deformation and the influence of the complex geo-structure within the tectonic mélange belt remain unclear.To address these questions,this study utilized a multidisciplinary approach,integrating on-site geological field mapping,surface deformation monitoring,multielectrode resistivity method,and deep displacement analysis.The aim was to evaluate the impact of the intricate geo-structure within the tectonic mélange belt on the Baige landslide events.Findings reveal that the landslide's geo-structure consists of structurally fractured,mesh-like rock masses,including heterogeneous lenticular rock masses and intermittent brittle shear zones distributed around the lens-shaped rock masses.The study underscores that the inhomogeneous and weakly deformed lenticular rock masses function as natural locked segments,governing the stability of the Baige landslide.Specifically,the relatively intact and hard granodiorite porphyry play a crucial role in locking the landslide's deformation.Deep displacement analysis indicates that the brittle shear zones act as the sliding surfaces.The progressive destruction of the locked segments and the gradual penetration of brittle shear zones,driven by gravitational potential energy,contribute to the landslide occurrence.This research provides critical insights into the formation mechanisms of large-scale landslides within tectonic mélange belts. 展开更多
关键词 Baige landslides Jinsha River tectonic mélange belt internal geological structure macro-meso-micro scales rock mass strength heterogeneity locked effect mechanisms
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Spin-Momentum Locking Breakdown of Evanescent Electromagnetic Waves in a Metal-Gyromagnetic Interface
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作者 Yidong Zheng Jianfeng Chen +1 位作者 Wenyao Liang Zhi-Yuan Li 《Chinese Physics Letters》 2025年第8期54-68,共15页
Spin-momentum locking is widely regarded as an inherent property of evanescent waves,where the transverse spin angular momentum is intrinsically tied to the wave's polarization.This principle is well established i... Spin-momentum locking is widely regarded as an inherent property of evanescent waves,where the transverse spin angular momentum is intrinsically tied to the wave's polarization.This principle is well established in systems such as surface plasmon polaritons,surface elastic waves,and other evanescent modes.Here,we theoretically unveil an anomalous breakdown of spin-momentum locking in evanescent electromagnetic waves at a metalgyromagnetic interface.We show that the hybrid polarization of the field induces two successive reversals of transverse spin near the interface—directly violating the conventional locking between spin and momentum.As a result,identical chiral sources placed at different heights above the interface excite evanescent waves propagating in opposite directions,defying standard expectations.This discovery challenges the presumed universality of spin-momentum locking and opens new degrees of freedom for controlling wave propagation in photonic and plasmonic systems. 展开更多
关键词 hybrid polarization field evanescent electromagnetic waves evanescent modesherewe transverse spin angular momentum metalgyromagnetic interfacewe spin momentum locking surface plasmon polaritonssurface evanescent waveswhere
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2.5Gb/s 0.18μm CMOS Clock and Data Recovery Circuit 被引量:2
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作者 刘永旺 王志功 李伟 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第4期537-541,共5页
A 2.5Gb/s clock and data recovery (CDR) circuit is designed and realized in TSMC's standard 0.18/μm CMOS process. The clock recovery is based on a PLL. For phase noise optimization,a dynamic phase and frequency de... A 2.5Gb/s clock and data recovery (CDR) circuit is designed and realized in TSMC's standard 0.18/μm CMOS process. The clock recovery is based on a PLL. For phase noise optimization,a dynamic phase and frequency detector (PFD) is used in the PLL. The rms jitter of the recovered 2.5GHz clock is 2.4ps and the SSB phase noise is - 111dBc/Hz at 10kHz offset. The rms jitter of the recovered 2.5Gb/s data is 3.3ps. The power consumption is 120mW. 展开更多
关键词 clock recovery data recovery phase locked loop dynamic phase and frequency detector
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A two-stage injection locking amplifier based on a cavity magnonic oscillator
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作者 Mun Kim Chunlei Zhang +2 位作者 Chenyang Lu Jacob Burgess Can-Ming Hu 《Chinese Physics B》 2025年第6期154-159,共6页
A cavity magnonic oscillator uses the coupling of a planar transmission line oscillator(cavity) and spin excitations(magnons) in a ferrimagnetic material to achieve superior frequency stability and reduced phase noise... A cavity magnonic oscillator uses the coupling of a planar transmission line oscillator(cavity) and spin excitations(magnons) in a ferrimagnetic material to achieve superior frequency stability and reduced phase noise. Like many low phase noise oscillators, a cavity magnonic oscillator faces the challenge that its narrow resonance profile is not well suited for injection locking amplification. This work presents an improved design for such an oscillator configured as an injection locking amplifier(ILA) with an extended lock range. The proposed design features a two-stage architecture, consisting of a pre-amplification oscillator and a cavity magnonic oscillator, separated by an isolator to prevent backward locking.By optimizing the circuit parameters of each stage, the proposed design achieved an order of magnitude increase in lock range, when compared to its predecessors, all while preserving the phase noise quality of the input, making it well-suited for narrowband, sensitive signal amplification. Furthermore, this work provides a method for using oscillators with high spectral purity as injection locking amplifiers. 展开更多
关键词 cavity magnonic oscillator injection locking amplifier
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Construction monitoring of lock head base plate using distributed optical fibre sensing technique 被引量:1
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作者 宋占璞 施斌 +3 位作者 朱鸿鹄 沈梦芬 张丹 孙义杰 《Journal of Southeast University(English Edition)》 EI CAS 2015年第4期535-540,共6页
The concrete hydration heat release process of the base plate is monitored using Roman optical time domain reflectometry(ROTDR) sensing sensors. The monitoring data shows that the internal maximum temperature of the... The concrete hydration heat release process of the base plate is monitored using Roman optical time domain reflectometry(ROTDR) sensing sensors. The monitoring data shows that the internal maximum temperature of the base plate is about 54 ℃ after the concrete was cured for 120 h. The fiber Bragg grating (FBG) temperature sensors are adopted to measure the surface temperature of the concrete and the temperature results are used to compensate the data measured by the pulse-prepump Brillouin optical time-domain analyzer (PPP-BOTDA) to obtain the real concrete surface strain of the base plate. The monitoring data is analyzed to obtain a clear understanding of the strain state of the base plate under the effect of concrete hydration heat release. The monitoring results demonstrate the potential of distributed optical fibre sensing techniques as a powerful tool in real-time construction monitoring, and also provide an important insight into the design, construction and maintenance of large hydraulic structures. 展开更多
关键词 construction monitoring lock head base plate optical fibre sensing lock engineering CONCRETE
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肩关节镜下应用免打结技术Push-lock固定治疗肩关节复发性不稳 被引量:5
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作者 刘运晃 王明新 +3 位作者 姜华 孙小平 安佰京 邢更彦 《中国矫形外科杂志》 CAS CSCD 北大核心 2016年第20期1831-1833,共3页
[目的]分析肩关节镜下免打结技术Push—lock固定治疗复发性肩关节不稳的临床疗效。[方法]2010年3月-2014年10月,本科共采用肩关节镜下锚钉缝合和免打结技术Push—lock固定治疗复发性肩关节不稳36例,其中应用免打结技术21例。术后随访1... [目的]分析肩关节镜下免打结技术Push—lock固定治疗复发性肩关节不稳的临床疗效。[方法]2010年3月-2014年10月,本科共采用肩关节镜下锚钉缝合和免打结技术Push—lock固定治疗复发性肩关节不稳36例,其中应用免打结技术21例。术后随访12个月,并评定其疗效。[结果]采用肩关节ASES评分和Rowe评分对36例患者的术前及术后肩关节功能进行评估。36例患者术前、术后ASES评分分别为75.8分、93.7分,两者比较差异具有统计学意义;Rowe评分分别为33.6分、88.4分,两者比较差异具有统计学意义。所有患者术后均未出现再脱位。[结论]肩关节镜下免打结技术push—lock固定术是治疗复发性肩关节不稳合理、有效的治疗方法。 展开更多
关键词 肩关节镜 复发性不稳 免打结技术 Push—lock
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Lock-up装置在连续梁桥上的减震性能研究 被引量:16
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作者 张永亮 陈兴冲 颜志华 《世界地震工程》 CSCD 北大核心 2010年第2期48-52,共5页
以某客运专线上大跨连续梁桥为实际工程背景,研究了Lock-up装置对结构纵向抗震性能的影响。根据Lock-up装置在地震作用下具有反复锁止的受力特点,采用非线性时程分析方法,分析了锁止速度对结构减震性能的影响。结果表明:对于大跨连续梁... 以某客运专线上大跨连续梁桥为实际工程背景,研究了Lock-up装置对结构纵向抗震性能的影响。根据Lock-up装置在地震作用下具有反复锁止的受力特点,采用非线性时程分析方法,分析了锁止速度对结构减震性能的影响。结果表明:对于大跨连续梁桥,Lock-up装置能够充分发挥活动墩的抗震承载能力,有效地提高桥梁结构整体抗震性能。当锁止速度较小时,Lock-up装置可以采用大刚度连杆模拟,并假定其始终处于完全锁定状态。但当锁止速度较高时,应考虑Lock-up装置反复锁止的实际工作特点,否则应用上述计算方法所得的结果偏于不安全。 展开更多
关键词 时程分析 lock-UP装置 锁止速度 连续梁桥
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克服“Locking”发散性的有限元研究进展 被引量:2
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作者 周天孝 聂玉峰 +1 位作者 胡兵 谢小平 《力学进展》 EI CSCD 北大核心 2001年第4期509-526,共18页
从克服Locking发散性到高性能格式的研究发展是过去十年有限元法研究的一个重要方面.本文认为所谓高性能有限元方法是一种特别的低阶位移格式,它具有如下的理论和计算优点:(1)保持物理力学问题固有的数学物理特征;(2)... 从克服Locking发散性到高性能格式的研究发展是过去十年有限元法研究的一个重要方面.本文认为所谓高性能有限元方法是一种特别的低阶位移格式,它具有如下的理论和计算优点:(1)保持物理力学问题固有的数学物理特征;(2)因此,应用于工程数值模拟,它是“鲁棒”的、高效的.按此立场,评论介绍了在计算结构力学和计算流体力学中发展的克服两类Locking发散性的有限元方法. 展开更多
关键词 杂交 混合法 locking不稳定性 三维弹性分析 STOKES问题 高性能格式 数学物理特征 有限元 工程数值模拟 计算结构力学 计算流体力学 发散性
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Lock-up装置的作用机理与分析模型 被引量:11
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作者 夏修身 崔靓波 李建中 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2014年第12期1497-1502,共6页
为探讨Lock-up装置的分析模型,介绍了其构造、阐述了其作用机理,给出了Lock-up装置阻尼力的力学模型并提出了相应的数值模拟方法。基于某铁路桥梁,建立全桥有限空间模型,采用文中提出的模拟方法进行了Lock-up装置的减震性能分析,通过与... 为探讨Lock-up装置的分析模型,介绍了其构造、阐述了其作用机理,给出了Lock-up装置阻尼力的力学模型并提出了相应的数值模拟方法。基于某铁路桥梁,建立全桥有限空间模型,采用文中提出的模拟方法进行了Lock-up装置的减震性能分析,通过与常用的刚性连杆或主从约束模拟方法的比较,明确了刚性连杆模拟方法的适用条件。结果表明,Lock-up装置的地震作用过程比较复杂,当Lock-up装置能够激发出极大的阻尼力时,文中的模拟方法与常用的刚性连杆或主从约束模拟方法结果非常接近,通常情况按刚性连杆或主从约束模拟方法得到的结果偏大。 展开更多
关键词 lock-UP装置 分析模型 地震反应 阻尼力 桥梁
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Hem-o-lock夹在腹膜后腹腔镜下肾盂旁囊肿去顶术中的疗效评估 被引量:2
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作者 赵华 周锦波 +2 位作者 叶海榛 李萍 胡海兵 《中国医学创新》 CAS 2013年第20期119-120,共2页
目的:探讨Hem-o-lock夹在后腹腔镜肾盂旁囊肿去顶术中的疗效。方法:7例肾盂旁囊肿患者行后腹腔镜肾盂旁囊肿去顶+囊壁两侧各夹Hem-o-lock一枚。结果:7例手术均成功;手术时间平均60min;术中出血量平均30ml;术后住院时间平均4.2d;7例术后... 目的:探讨Hem-o-lock夹在后腹腔镜肾盂旁囊肿去顶术中的疗效。方法:7例肾盂旁囊肿患者行后腹腔镜肾盂旁囊肿去顶+囊壁两侧各夹Hem-o-lock一枚。结果:7例手术均成功;手术时间平均60min;术中出血量平均30ml;术后住院时间平均4.2d;7例术后随访6~24个月,均无复发。结论:后腹腔镜肾盂旁囊肿去顶+囊壁两侧各夹Hem-o-lock一枚可有效减少肾盂囊肿复发,且手术操作安全简单。 展开更多
关键词 肾盂旁囊肿 后腹腔镜 Hem-o-lock
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