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Effect of lung lavage via fiber bronchoscope combined with non-invasive positive pressure ventilation on the blood gas results and systemic state of patients with COPD complicated by severe pneumonia 被引量:1
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作者 Chang-Hao Yao Zhao-Hua Dai Rui-Li Chai 《Journal of Hainan Medical University》 2017年第22期87-90,共4页
Objective: To discuss the effect of lung lavage via fiber bronchoscope combined with non-invasive positive pressure ventilation on the blood gas results and systemic state of patients with COPD complicated by severe p... Objective: To discuss the effect of lung lavage via fiber bronchoscope combined with non-invasive positive pressure ventilation on the blood gas results and systemic state of patients with COPD complicated by severe pneumonia. Methods: A total of 68 patients with COPD complicated by severe pneumonia who were treated in the hospital between November 2015 and April 2017 were collected, retrospectively analyzed and then divided into the group A (n=35) who received noninvasive positive pressure ventilation and the group B (n=33) who received lung lavage via fiber bronchoscope combined with non-invasive positive pressure ventilation. The differences in arterial blood gas and serum index levels were compared between the two groups before and after treatment. Results: Before treatment, there was no statistically significant difference in arterial blood gas index levels as well as serum contents of inflammatory mediators, stress hormones and myocardial enzyme spectrum indexes between the two groups. After treatment, arterial blood gas indexes PH and PaO2 levels of group B were higher than those of group A;serum inflammatory mediators HMGB1, PCT and hs-CRP contents were lower than those of group A;serum stress hormones Cor, AngⅠ and AngⅡcontents were lower than those of group A;serum myocardial enzyme spectrum indexesα-HBDH and cTn-Ⅰ contents were lower than those of group A. Conclusion: Lung lavage via fiber bronchoscope combined with non-invasive positive pressure ventilation can effectively optimize the arterial blood gas levels, reduce systemic inflammatory stress state and protect the myocardial function of patients with COPD complicated by severe pneumonia. 展开更多
关键词 COPD Severe PNEUMONIA Non-invasive positive pressure ventilation Lung LAVAGE VIA fiber BRONCHOSCOPE
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Fiber Migration and Distribution of Twist at Different Radial Positions of Rotor Yarn-by Hi-Scope Video Microscope System 被引量:5
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作者 王善元 CHEUNG H.W. +2 位作者 张宏伟 LO M.T. 卢明德 《Journal of Donghua University(English Edition)》 EI CAS 2002年第3期45-47,共3页
This paper describes systematic measurement of fiber migration and distribution pattern of twist at different radial positions of rotor spun yarn mixed tracer fiber by Hi-Scope Video Microscope System. The positions o... This paper describes systematic measurement of fiber migration and distribution pattern of twist at different radial positions of rotor spun yarn mixed tracer fiber by Hi-Scope Video Microscope System. The positions of tracer fibers were measured in three dimensions accurately, and the migration index and the twist distribution at different radial positions of rotor yarn were calculated and analyzed. This research result serves to provide useful references for further study on the structural mechanics of rotor spun yarn. 展开更多
关键词 rotor yarn fiber migration twist distribution at different radial positions.
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Effects of planting dates and shading on carbohydrate content,yield,and fiber quality in cotton with respect to fruiting positions 被引量:2
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作者 ZHAO Wen-qing WU You +5 位作者 Zahoor Rizwan WANG You-hua MA Yi-na CHEN Bing-lin MENG Ya-li ZHOU Zhi-guo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第5期1106-1119,共14页
Two cotton(Gossypium hirsutum L.) cultivars, Kemian 1(cool temperature-tolerant) and Sumian 15(cool temperaturesensitive) were used to study the effects of cool temperature on carbohydrates, yield, and fiber qua... Two cotton(Gossypium hirsutum L.) cultivars, Kemian 1(cool temperature-tolerant) and Sumian 15(cool temperaturesensitive) were used to study the effects of cool temperature on carbohydrates, yield, and fiber quality in cotton bolls located at different fruiting positions(FP). Cool temperatures were created using late planting and low light. The experiment was conducted in 2010 and 2011 using two planting dates(OPD, the optimized planting date, 25 April; LPD, the late planting date, 10 June) and two shading levels of crop relative light rate(CRLR, 100 and 60%). Compared with fruiting position 1(FP1), cotton yield and yield components(fiber quality, leaf sucrose and starch content, and fiber cellulose) were all decreased on FP3 under all treatments. Compared with OPD-CRLR 100%, other treatments(OPD-CRLR 60%, LPD-CRLR 100%, and LPD-CRLR 60%) had significantly decreased lint yield at both FPs of both cultivars, but especially at FP3 and in Sumian 15; this decrease was mainly caused by a large decline in boll number. All fiber quality indices decreased under late planting and shading except fiber length at FP1 with OPD-CRLR 60%, and a greater reduction was observed at FP3 and in Sumian 15. Sucrose content of the subtending leaf and fiber increased under LPD compared to OPD, whereas it decreased under CRLR 60% compared to CRLR 100%, which led to decreased fiber cellulose content. Therefore, shading primarily decreased the "source" sucrose content in the subtending leaf whereas late planting diminished translocation of sucrose towards cotton fiber. Notably, as planting date was delayed and light was decreased, more carbohydrates were distributed to leaf and bolls at FP1 than those at FP3, resulting in higher yield and better fiber quality at FP1, and a higher proportion of bolls and carbohydrates allocated at FP3 of Kemian 1 compared to that of Sumian 15. In conclusion, cotton yield and fiber quality were reduced less at FP1 compared to those at FP3 under low temperature and low light conditions. Thus, reduced cotton yield and fiber quality loss can be minimized by selecting low temperature tolerant cultivars under both low temperature and light conditions. 展开更多
关键词 cotton planting date and shading fruiting position yield fiber quality
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Position-sensitive plastic scintillator detector with WLS-fiber readout 被引量:1
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作者 Jia-Ning Dong Yun-Long Zhang +4 位作者 Zhi-Yong Zhang Dong Liu Zi-Zong Xu Xiao-Lian Wang Shu-Bin Liu 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第8期186-192,共7页
In this paper,the design,construction,simulation,and performance of a position-sensitive plastic scintillator detector are presented.The readout of the detector uses wavelength-shifting fibers coupled with multi-anode... In this paper,the design,construction,simulation,and performance of a position-sensitive plastic scintillator detector are presented.The readout of the detector uses wavelength-shifting fibers coupled with multi-anode photomultipliers(PMTs) for the x-and y-dimensions.After calibrating the multi-anode PMTs,a two-dimensional projection image of the square scintillator telescope hit by cosmic muons is demonstrated.By performing a cosmic test with the Micromegas telescope,the position resolution of the detector was determined to reach approximately8.6 mm,which is close to the value obtained in physical simulation. 展开更多
关键词 闪烁器 纤维结 位置 塑料 敏感 读出 WLS 光电倍增管
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Influence of Anthesis Date and Boll Branch Position on Qualities and Super-molecular Structure of Cotton Fiber
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作者 SHAN Shi-hua, SHI Pei, SUN Xue-zhen, ZHOU Zhi-guo and BIAN Dong-cai(Agronomy Department of Shandong Agricultural University, Taian 271018 , P. R . China Tianjin Institute of Textile , Tianjin 300160 , P.R. China ) 《Agricultural Sciences in China》 CAS CSCD 2002年第6期636-641,共6页
The influences of the anthesis date and the fruiting branch positions on parameters of cotton fiber quality and super-molecular structure were studied. Fiber quality parameters, such as cotton fiber length, micronair,... The influences of the anthesis date and the fruiting branch positions on parameters of cotton fiber quality and super-molecular structure were studied. Fiber quality parameters, such as cotton fiber length, micronair, maturity and fiber strength deteriorated with postponing the anthesis date and decreasing temperature. When anthesis happened on the same date, the fruiting branch positions affected the fiber quality parameters, and the fiber quality parameters of the lower portion turned out to be higher than that of the upper portion, although the difference was insignificant. The super-molecular structure of the lower portion turned out to be superior to that of the upper portion at the early anthesis date and high temperature, which is in accordance with what was mentioned above, but the fruiting branch positions did not affect the impact of the anthesis date on the super-molecular structure. 展开更多
关键词 COTTON Anthesis date Fruiting branch positions fiber qualities Super-molecular structure
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Application of the Spectrum Peak Positioning Technology Based on BP Neural Network in Demodulation of Cavity Length of EFPI Fiber Optical Sensor
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作者 Mengran Zhou Mengya Nie 《Journal of Computer and Communications》 2013年第7期67-71,共5页
An Extrinsic Fabry-Perot Interferometric (EFPI) fiber optical sensor system is an online testing system for the gas density. The system achieves the measurement of gas density information mainly by demodulating the ca... An Extrinsic Fabry-Perot Interferometric (EFPI) fiber optical sensor system is an online testing system for the gas density. The system achieves the measurement of gas density information mainly by demodulating the cavity length of EF- PI fiber optical sensor. There are many ways to achieve the demodulation of the cavity length. For shortcomings of the big intensity demodulation error and complex structure of phase demodulation, this paper proposes that BP neural net-work is used to locate the special peak points in normalized interference spectrum and combining the advantages of the unimodal and bimodal measurement achieves the demodulation of the cavity length. Through online simulation and actual measurement, the results show that the peak positioning technology based on BP neural network can not only achieve high-precision demodulation of the cavity length, but also achieve an absolute measurement of cavity length in large dynamic range. 展开更多
关键词 EFPI fiber Optical Sensor The DEMODULATION of CAVITY Length BP NEURAL Network The PEAK positIONING Technology
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基于FiberSIM激光投影定位技术在蜂窝面板上的设计与应用
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作者 王笛 张松 +2 位作者 陈浩然 荆佳奇 曲广岩 《纤维复合材料》 CAS 2023年第4期21-24,45,共5页
本文介绍了航空航天常用夹层结构蜂窝面板,针对蜂窝面板在成型时存在的问题,根据复合材料铺层设计准则设计了复合材料蜂窝面板铺层,基于FiberSIM软件平台,仿真模拟了复合材料蜂窝面板各铺层,并生成激光投影数据供定位使用。建立了复合... 本文介绍了航空航天常用夹层结构蜂窝面板,针对蜂窝面板在成型时存在的问题,根据复合材料铺层设计准则设计了复合材料蜂窝面板铺层,基于FiberSIM软件平台,仿真模拟了复合材料蜂窝面板各铺层,并生成激光投影数据供定位使用。建立了复合材料蜂窝面板的设计流程,针对复合材料蜂窝面板因铺层角度不准导致固化后易翘曲变形的问题,在成型过程中借助激光投影仪提高铺层角度精度,成型的复合材料蜂窝面板表面光滑,平面度高,四周无翘曲变形现象,无损探伤结果表明面板无分层现象,满足蜂窝对面板的高质量要求。 展开更多
关键词 蜂窝面板 碳纤维复合材料 fibersIM 激光定位
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一种改进的数字Ultra-Wide Bandwidth Radio-on-Fiber系统模型的性能分析
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作者 齐永兴 刘元安 高泽华 《北京邮电大学学报》 EI CAS CSCD 北大核心 2005年第4期62-65,共4页
为了充分利用超宽带的特点,对数字光载无线系统进行了改进,并给出了系统模型.理论分析和仿真结果表明,跳时序列构造不同,系统性能(信噪比)也不同;相同构造下,激活用户数不同引起的时隙平均干扰也不同.这种改进使得数字光载无线系统降低... 为了充分利用超宽带的特点,对数字光载无线系统进行了改进,并给出了系统模型.理论分析和仿真结果表明,跳时序列构造不同,系统性能(信噪比)也不同;相同构造下,激活用户数不同引起的时隙平均干扰也不同.这种改进使得数字光载无线系统降低了复杂度,提高了光纤利用率,同时也改善了系统的性能. 展开更多
关键词 光载无线 超宽带 脉冲位置调制
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伺服控制系统在纤维喷涂器上的应用
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作者 李明昊 《橡塑技术与装备》 2025年第3期63-65,共3页
用伺服控制系统对纤维制品喷涂工艺进行改造,代替原本的人工喷涂。详细说明了电气主控系统的配置,硬件组态过程,自整定方法,软件编程等。使用后,系统控制准确可靠,制品喷涂均匀,可以提高生产效率,增加制品产量。
关键词 纤维喷涂器 伺服驱动器 位置控制 以太网通讯
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PTC/NTC Behavior of PVDF Composites Filled with GF and CF 被引量:3
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作者 WANG Xin-lei ZHANG Guo LI Ji-xin LI Zhuo-shi LIU Zhan-fang LIU Xiu-qi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第5期648-652,共5页
Conductive polyvinylidene fluoride(PVDF)matrix composites filled with graphited fiber(GF)or carbon fiber(CF)were prepared by the melt-mixing method.The breakage and length distribution of the fibers in the polym... Conductive polyvinylidene fluoride(PVDF)matrix composites filled with graphited fiber(GF)or carbon fiber(CF)were prepared by the melt-mixing method.The breakage and length distribution of the fibers in the polymer matrix were studied by scanning electron microscope(SEM)and optical microscope(OM)observations,respectively. The differences in the positive temperature coefficient(PTC)effects of the composites were mainly attributed to inter-fiber contact ability.The elimination of the negative temperature coefficient(NTC)effect for CF/PVDF composite was because of an increase in the viscosity of the polymer matrix.With the same filler content,CF could be more effective,to eliminate the NTC effect when compared with GF.Addition of 2%CF(mass fraction)in the PVDF composite with 7%GF(mass fraction)could effectively eliminate the NTC phenomenon of the composite. 展开更多
关键词 Polyvinylidene fluoride Graphited fiber Carbon fiber positive temperature coefficient effect Negative temperature coefficient effect
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A Novel Method for the Design of Fiber Gratings
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作者 戴恩光 《High Technology Letters》 EI CAS 1999年第2期16-18,共3页
A new weighting technique compatible with phase mask technique and point by point technique is proposed. The design method allows precise weighting of the fiber grating using controlled interference of reflected waves... A new weighting technique compatible with phase mask technique and point by point technique is proposed. The design method allows precise weighting of the fiber grating using controlled interference of reflected waves. Based upon the new position weighting method, complex shape of fiber grating spectra can be acquired effectively . 展开更多
关键词 fiber GRATING positION Weighting PHASE MASK
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Adaptive Performance Improvement of Fiber Bragg Grating in Radio over Fiber System
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作者 Fabrice Mfuamba Kabonzo Yunfeng Peng 《Journal of Computer and Communications》 2016年第3期1-6,共6页
The combination of Radio Frequency and Optical Fiber has resulted high capacity transmission at lower costs components and makes Radio over Fiber as a current trend of large broadband communication. In Fiber optics fi... The combination of Radio Frequency and Optical Fiber has resulted high capacity transmission at lower costs components and makes Radio over Fiber as a current trend of large broadband communication. In Fiber optics field, the use of Fiber Bragg Grating (FBG) was been proposed in recent research with different purpose of uses. However, the compensation of dispersion method of Fiber Bragg Grating (FBG) can boost significantly the system performance. This paper investigates the performance capacity improvement of adaptive Radio over Fiber system. The system design was performed using OptiSystem 7.0 software, which 10 Gb/s Non Return to Zero (NRZ) signal was launched into 50 Km Universal Mode Fiber and Fiber Bragg Grating was used as a compensator of dispersion before frequency up conversion. Therefore, the system performances were investigated by comparing the Bit Error Rate (BER) and Q-factors of Positive Intrinsic Negative (PIN) and Ultrafast Avalanche Photodiode (APD) as optical receivers. The Eye diagram analyzer showed acceptable improvement due to use of Fiber Bragg Grating as a compensator of dispersion. 展开更多
关键词 Radio over fiber (RoF) fiber Bragg Grating (FBG) Dispersion Compensating fiber (DCF) positive Intrinsic Negative (PIN) Ultrafast Avalanche Photodiode (APD)
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A new method for position-sensitive measurement of beta surface contamination
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作者 Yan-Tao Qu Hui Wang +4 位作者 Yang Liu Ling Chen Jie Hou Zhe Liu Ji-Zeng Ma 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第2期49-56,共8页
In this paper, we propose a new method for position-sensitive measurement of beta surface contamination. With a position-sensitive detector of enlarged sensitive detection area, accurate information of the contaminati... In this paper, we propose a new method for position-sensitive measurement of beta surface contamination. With a position-sensitive detector of enlarged sensitive detection area, accurate information of the contamination distribution can be obtained. The positionsensitive detection is based on a large-area plastic scintillator and the wavelength shifting(WLS) fibers and adopts the ‘‘light center of gravity'' method. Optical transmission of the detector is simulated with a preliminary detector model, and feasibility of the detector design and measurement method is evaluated using an experiment system.The simulation and experiment results at different beta-ray incident points on the scintillator surface show that there is a polynomial relationship between the average amplitude ratio of the output pulses from the two parallel WLS fibers in the same fiber layer and the relative distance from the incident point to the WLS fiber. 展开更多
关键词 BETA surface CONTAMINATION positION-SENSITIVE measurement WAVELENGTH SHIFTING fibers Plastic scintillator
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水液压柱塞泵滑靴球窝副收口工艺与效果分析
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作者 李东林 马先帅 +3 位作者 赵峰 李跃 赵中校 刘银水 《机电工程》 CAS 北大核心 2024年第11期2012-2018,共7页
滑靴球窝副是水液压柱塞泵连接柱塞和滑靴的关键摩擦副,其收口质量直接影响泵的可靠性和寿命。针对由金属基体包覆塑性材料碳纤维增强聚醚醚酮(CFRPEEK)耐磨层组成的滑靴球窝副收口部位松动的问题,对模压收口和直接注塑收口两种成型工... 滑靴球窝副是水液压柱塞泵连接柱塞和滑靴的关键摩擦副,其收口质量直接影响泵的可靠性和寿命。针对由金属基体包覆塑性材料碳纤维增强聚醚醚酮(CFRPEEK)耐磨层组成的滑靴球窝副收口部位松动的问题,对模压收口和直接注塑收口两种成型工艺进行了研究,分析了不同成型工艺滑靴球窝副的收口效果。首先,建立了滑靴球窝副的有限元模型;然后,运用仿真软件ANSYS对柱塞滑靴的收口及拉脱过程进行了模拟仿真,研究了滑靴收口部位的等效应力和应变的变化,对比分析了316L和17-4PH两种滑靴基体材料以及两种收口成型工艺对拉脱力的影响情况;最后,将两种收口成型工艺的柱塞滑靴组件分别安装在水液压泵内,并进行了运行试验,结合测试结果对仿真结果进行了验证。研究结果表明:与模压收口成型工艺相比,采用直接注塑收口工艺的滑靴球窝副从根本上消除了残余应力,相同结构下,其拉脱力增大了20.29%;长时间运行后其收口效果良好,未出现明显的轴向间隙。 展开更多
关键词 容积泵 滑靴球窝副 碳纤维增强聚醚醚酮 模压收口成型工艺 直接注塑成型工艺 拉脱力 残余应力
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VAE乳胶粉/碳纤维复合改性混凝土的力学性能 被引量:2
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作者 王志航 白二雷 +2 位作者 周俊鹏 刘高杰 杨宁 《建筑材料学报》 EI CAS CSCD 北大核心 2024年第6期487-495,共9页
为探究醋酸乙烯酯-乙烯共聚物(VAE)乳胶粉和碳纤维对混凝土力学性能的混杂改性效果及机理,制备了1种VAE乳胶粉改性混凝土(VAEMC)、3种碳纤维改性混凝土(CFMC)和3种VAE乳胶粉/碳纤维复合改性混凝土(VAE/CFMC),测试了改性混凝土的电阻率... 为探究醋酸乙烯酯-乙烯共聚物(VAE)乳胶粉和碳纤维对混凝土力学性能的混杂改性效果及机理,制备了1种VAE乳胶粉改性混凝土(VAEMC)、3种碳纤维改性混凝土(CFMC)和3种VAE乳胶粉/碳纤维复合改性混凝土(VAE/CFMC),测试了改性混凝土的电阻率和力学性能,并进行了扫描电镜试验和压汞试验.结果表明:VAE乳胶粉可以促进碳纤维的分散,VAE/CFMC的电阻率小于CFMC;与CFMC相比,VAE/CFMC的力学性能更佳;VAE乳胶粉与碳纤维具有“正混杂效应”,复掺VAE乳胶粉与碳纤维时,混凝土的力学性能呈现出“1+1>2”的复合增强效果;VAE乳胶粉可以优化CFMC的孔隙结构,细化其孔径,增强碳纤维/混凝土基体界面的物理结合,使碳纤维的破坏形式由拉滑破坏转变为拉断破坏. 展开更多
关键词 混凝土 碳纤维 VAE乳胶粉 力学性能 正混杂效应 界面
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冗余铺放机器人的自运动流形及逆解优化研究 被引量:1
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作者 李奎 徐孝彬 +1 位作者 王婷婷 刘波 《机电工程》 CAS 北大核心 2024年第3期551-558,共8页
针对用于复合材料铺放成型的八自由度冗余机器人系统的逆运动学问题,提出了一种求解其自运动流形及逆解优化的算法。首先,基于位姿分离思想定义了位置子流形和姿态子流形,采用几何求解法得到了基于自运动变量的参数化方程形式的位置子... 针对用于复合材料铺放成型的八自由度冗余机器人系统的逆运动学问题,提出了一种求解其自运动流形及逆解优化的算法。首先,基于位姿分离思想定义了位置子流形和姿态子流形,采用几何求解法得到了基于自运动变量的参数化方程形式的位置子流形和姿态子流形;然后,根据机器人的关节约束和实际铺放工艺过程,对给定的铺放位姿进行了位置子流形和姿态子流形配对的仿真,并用流形中若干组逆解通过正向运动学得到了末端位姿矩阵(其结果均与给定位姿相符,从而验证了自运动流形求解过程的正确性);最后,在完成自运动流形求解的基础上,从机械臂运动的平滑性和关节运动变化量两个方面出发,提出了一种基于自运动变量参数化方程的全局优化目标函数;以飞机尾椎模型为实验研究对象,对其中一条铺放路径进行了逆解全局优化仿真,得到了自运动变量和机器人各关节角在铺放路径上的优化曲线,将仿真结果与一种多目标优化算法进行了比较。研究结果表明:针对相同的铺放路径,采用上述优化算法后关节角变化总量降低了11.25%;该算法能够有效地求解八自由度冗余铺放机器人系统的自运动流形,基于全局优化目标函数,其能够在自运动流形中寻找出自运动变量和机器人各关节的最优解。该算法同样也适用于其他位姿解耦的冗余机器人系统逆解问题的求解。 展开更多
关键词 冗余铺放机器人 八自由度 几何法 位姿分离 自运动流形 逆解优化
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微小角中子散射谱仪的高分辨中子闪烁体探测器研究
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作者 刘慧银 杨洁 +11 位作者 黄畅 唐彬 周诗慧 蔡小杰 王修库 曾莉欣 岳秀萍 陈少佳 许虹 郭大威 陈旭 孙志嘉 《核技术》 EI CAS CSCD 北大核心 2024年第2期66-75,共10页
微小角中子散射谱仪是中国散裂中子源(China spallation neutron source,CSNS)工程目前在建的谱仪之一,为了实现微小角散射模式下中子衍射的精确测量,要求中子探测器的位置分辨≤2 mm、探测效率≥60%@0.4 nm。在此物理精度需求下,研制... 微小角中子散射谱仪是中国散裂中子源(China spallation neutron source,CSNS)工程目前在建的谱仪之一,为了实现微小角散射模式下中子衍射的精确测量,要求中子探测器的位置分辨≤2 mm、探测效率≥60%@0.4 nm。在此物理精度需求下,研制了基于^(6)LiF/ZnS(Ag)闪烁屏、波移光纤阵列和硅光电倍增管(Silicon Photomultiplier,SiPM)结构的位置灵敏型闪烁体探测器,以实现热中子的高效率和高分辨实时探测。探测效率测试以标准3He管的入射中子数归一化计算得到,位置分辨通过含有“CSNS”字样的含硼铝板验证。本文详细研究了0.5 mm直径波移光纤的光传输性能,对比了不同硅光电倍增管的增益和热噪声特性,并以此设计了有效面积为300 mm×300 mm的探测器工程样机。经测试,该探测器的位置分辨为1.2 mm×1.2 mm,探测效率为(61.8±0.2)%@0.4 nm,达到了工程设计指标,满足了CSNS工程微小角谱仪的中子衍射测量需求。 展开更多
关键词 闪烁体探测器 硅光电倍增管 波移光纤 位置分辨 探测效率
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入路姿态光纤导航的经鼻柔性手术机器人
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作者 李天梁 朱永文 +3 位作者 李佳隽 王峻 孟伟 谭跃刚 《光学精密工程》 EI CAS CSCD 北大核心 2024年第19期2861-2876,共16页
针对深腔狭小空间下传统经鼻手术操作灵巧性不足、术中入路导航信息匮乏等问题,提出了入路姿态光纤导航的经鼻柔性手术机器人。采用柔性球铰串联和销钉-滑槽配置,设计出兼具灵巧和抗扭扰动的柔性机械臂构型,结合几何分析和D-H参数法建... 针对深腔狭小空间下传统经鼻手术操作灵巧性不足、术中入路导航信息匮乏等问题,提出了入路姿态光纤导航的经鼻柔性手术机器人。采用柔性球铰串联和销钉-滑槽配置,设计出兼具灵巧和抗扭扰动的柔性机械臂构型,结合几何分析和D-H参数法建立了手术机器人正、逆运动学模型;通过在各柔性机械臂内间隔90°嵌入两路分布式光纤导航传感器,联合双目视觉和极限学习机提出的数据驱动的入路姿态光纤原位标定法,避免了传统离线标定导致的测量误差及基于微分几何理论获取其姿态方法中误差累积的问题,实现了手术机器人术中形位高精度自感知。实验结果表明:柔性机械臂的极限弯曲角度可达105°,弯曲角80°范围内容许负载为0.9 N;通过光纤导航,在自由和障碍物环境中,柔性机械臂末端最大位置预测误差分别为0.920 mm,1.635 mm,验证了本文提出的入路姿态光纤导航的经鼻柔性手术机器人有效性和可行性。 展开更多
关键词 光纤导航 柔性手术机器人 极限学习机 位置跟踪
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全光纤微震监测技术在底板突水监测中的应用研究
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作者 黄刚 韩云春 +6 位作者 余国锋 罗勇 任波 叶赞 王立超 赵靖 徐一帆 《工矿自动化》 CSCD 北大核心 2024年第6期36-45,共10页
目前国内的光纤微震监测系统多是基于光学光栅传感技术,而光纤光栅波长解调限制了系统检测频率与灵敏度,且长时间、连续不间断的微震监测成功案例较少。针对上述问题,提出了一种新型全光纤微震监测系统。以潘二煤矿11023工作面回采过程... 目前国内的光纤微震监测系统多是基于光学光栅传感技术,而光纤光栅波长解调限制了系统检测频率与灵敏度,且长时间、连续不间断的微震监测成功案例较少。针对上述问题,提出了一种新型全光纤微震监测系统。以潘二煤矿11023工作面回采过程中底板突水监测为工程背景,使用全光纤微震监测系统与ESG微震监测系统进行对比,得出全光纤微震监测系统具有以下优势:记录的波形频谱特征更清晰,表现出高信噪比优势;对扰动深度的监测范围更大,远距离监测效果更好;震源定位结果分布更加合理,更符合工作面实际开采情况。在监测工作面回采全周期内,分析了11023工作面断层异常区底板破坏与微震活动性关系:在断层和煤层变薄异常区附近,微震事件的数量增多、强度增大;工作面初采期间应力集中释放,受采动影响,底板破坏较深;相对大能量事件主要分布在断层异常区的底板,底板破坏深度约为27 m,微震事件在3煤底板60 m以下没有成线或成面聚集的情况,说明裂隙并未扩展,未形成导水通道,工作面安全回采。 展开更多
关键词 全光纤微震监测 底板突水 扰动深度 震源定位 断层异常区 微震活动性 相对大能量事件
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基于时域曲线相关性鉴别的分布式光纤扰动定位算法研究 被引量:1
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作者 黄闽南 范佳铭 +3 位作者 王一山 苏幸晨 张成龙 吕立冬 《仪表技术与传感器》 CSCD 北大核心 2024年第2期93-97,103,共6页
针对瑞利散射信号的随机性以及光纤衰减导致分布式光纤传感系统扰动定位困难、事件误报率高的问题,根据瑞利散射曲线的时域相关性,提出了基于滑动窗的相关系数的扰动事件校验与定位算法。该算法根据在发生扰动事件时相邻周期的光时域反... 针对瑞利散射信号的随机性以及光纤衰减导致分布式光纤传感系统扰动定位困难、事件误报率高的问题,根据瑞利散射曲线的时域相关性,提出了基于滑动窗的相关系数的扰动事件校验与定位算法。该算法根据在发生扰动事件时相邻周期的光时域反射曲线、扰动点及后续位置相关性骤降的特征,在相邻两周期的光时域反射曲线末端设置数据窗并计算相关系数,设定相关系数的阈值校验有无扰动事件发生。若判别存在扰动事件,则向前滑动数据窗并计算相关系数,然后与定位阈值对比从而定位事件。文中搭建了分布式光纤振动传感系统,在25 km长的光纤范围内实现了±3 m的定位误差、±5 m的空间分辨率,系统响应时间仅为0.15 s。 展开更多
关键词 分布式光纤传感 扰动定位 相关性 瑞利散射 光时域反射
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