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悬线有夹角的三维悬线式蓝光光学头力矩器的仿真研究
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作者 胡盛勇 郑津津 +2 位作者 黄文浩 沈连婠 周洪军 《计算机应用与软件》 CSCD 北大核心 2012年第1期31-33,87,共4页
对具有聚焦、循迹和倾斜补偿功能的悬线带夹角的三个运动自由度的蓝光光学头三维悬线式力矩器建立了模型,以有限元作为分析手段,分析了其空间磁场和受力情况。模态分析得到力矩器循迹、聚焦和倾斜三个模态分别为50.470Hz、54.754Hz和205... 对具有聚焦、循迹和倾斜补偿功能的悬线带夹角的三个运动自由度的蓝光光学头三维悬线式力矩器建立了模型,以有限元作为分析手段,分析了其空间磁场和受力情况。模态分析得到力矩器循迹、聚焦和倾斜三个模态分别为50.470Hz、54.754Hz和205.23Hz,分别与实验比较误差小于1%。等效阻尼系统来模拟阻尼胶的阻尼效果,谐响应分析得到力矩器的特性曲线多普勒曲线。通过与实验比较,所建立的模型能够真实地反映该力矩器的特性。 展开更多
关键词 光光 三维悬线式力矩器 有限元法 模态分析 谐响应分析
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用于蓝光光学头的力矩器的动力学特性分析
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作者 张利军 《机电工程技术》 2009年第2期53-56,共4页
作为光学读取头中的最终执行部件,力矩器在驱动电流的作用下带动物镜上下运动,高频动态跟踪光盘上信息坑位置的高频小幅移动,力矩器的动态性能直接决定着聚焦伺服和循迹伺服的精度,也就决定着光学头的读盘性能。本文结合蓝光光学头这一... 作为光学读取头中的最终执行部件,力矩器在驱动电流的作用下带动物镜上下运动,高频动态跟踪光盘上信息坑位置的高频小幅移动,力矩器的动态性能直接决定着聚焦伺服和循迹伺服的精度,也就决定着光学头的读盘性能。本文结合蓝光光学头这一项目,针对用于蓝光光学头中的力矩器,用有限元方法进行了动力学仿真分析。首先建立了力矩器的有限元模型,设置材料参数并划分或建立单元;接着进行了力矩器可动部的模态分析,并对几种特定模态进行了阐述;然后进行了力矩器可动部的谐响应分析;最后给出了实验测试结果,验证了仿真模型的有效性。 展开更多
关键词 力矩器 光光 有限元 模态分析 谐响应分析
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木偶小戏《差役与犯人》
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作者 庄火明 《福建艺术》 2006年第5期78-79,共2页
[一条山路伸向“春来”酒店门外,店内的大窗尤为醒目,陈设桌椅、酒罐。[差役内声:“走哇!”他披着长发,一手执棍棒,一手拿酒壶,踉踉跄跄地押解貌似和尚的秃头犯人上。他们已经走了很长的路,显得疲倦。差役(拿起酒壶,呷了一口)痛快,痛快... [一条山路伸向“春来”酒店门外,店内的大窗尤为醒目,陈设桌椅、酒罐。[差役内声:“走哇!”他披着长发,一手执棍棒,一手拿酒壶,踉踉跄跄地押解貌似和尚的秃头犯人上。他们已经走了很长的路,显得疲倦。差役(拿起酒壶,呷了一口)痛快,痛快呀!犯人差爷,给小的喝一口吧?差役休想!这壶酒,本差爷还喝不过瘾呢!我说犯人呀,去府衙还有几里路。快走!犯人走就走。(差役与犯人圆场)差役(唱)酒壶,棍棒,伴我走四方。当差役,押人犯,全凭眼睛亮。犯人秃头光光,我是头发长长,头光光,发长长,我与他,不一样,彼此特征不能忘。(招手)犯人,过来,过来!犯人是。(走近差役)差役(命令地)蹲下!犯人差爷,您又要摸我的秃头?差役(厉声)蹲下!犯人好的!(蹲在地上)差役别动!(抚摸犯人的秃头)嗯,秃头光溜溜,正是犯人。喂。 展开更多
关键词 头光光 差役 犯人 人役
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Reproducibility of splicer-based long-period fiber gratings for gain equalization 被引量:2
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作者 I. Cacciari M. Brenci +3 位作者 R. Falciai G. Nunzi Conti S. Pelli G. C. Righini 《Optoelectronics Letters》 EI 2007年第3期203-206,共4页
We fabricated long-period fiber gratings (LPFGs) using electric arc discharges. We observed that the fiber becomes slightly tapered due to longitudinal tension during the arc: this effect depends on the arc current... We fabricated long-period fiber gratings (LPFGs) using electric arc discharges. We observed that the fiber becomes slightly tapered due to longitudinal tension during the arc: this effect depends on the arc current and time length. We experimentally investigated how these characteristics can influence grating's performances, especially in view of employing the LPFG as gain equalizer for an erbium-doped optical amplifier. As expected, we found that the spectral response of the grating depends on the period A, the intensity of the perturbation, the grating length and the type of mode-coupling induced. Since this last parameter cannot be estimated directly from the transmission spectra, we propose a method to determine the modecoupling occurring in the device and to assess the index modulation induced by the electric arcs. This method combines both experimental and simulated data, and can be used to characterize LPFGs made-up by any method. 展开更多
关键词 长周期光纤光栅 光纤接 增益均衡 再现性 电弧放电
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Excited-State Proton Transfer and Decay in Hydrogen-Bonded Oxazole System: MS-CASPT2//CASSCF Study
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作者 谢斌斌 李春香 +1 位作者 崔刚龙 方道 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第1期38-46,I0001,共10页
Herein we have employed high-level multi-reference CASSCF and MS-CASPT2 electronic structure methods to systematically study the photochemical mechanism of intramolecularly hydrogen-bonded 2-(2'-hydroxyphenyl)-4-me... Herein we have employed high-level multi-reference CASSCF and MS-CASPT2 electronic structure methods to systematically study the photochemical mechanism of intramolecularly hydrogen-bonded 2-(2'-hydroxyphenyl)-4-methyloxazole. At the CASSCF level, we have optimized minima, conical intersections, minimum-energy reaction paths relevant to the excited-state intramolecular proton transfer (ESIPT), rotation, photoisomerization, and the excited-state deactivation pathways. The energies of all structures and paths are refined by the MS-CASPT2 method. On the basis of the present results, we found that the ESIPT process in a conformer with the OH... N hydrogen bond is essentially barrierless process; whereas, the ESIPT process is inhibited in the other conformer with the OH... O hydrogen bond. The central single-bond rotation of the S1 enol species is energetically unfavorable due to a large barrier. In addition, the excited-state deactivation of the S1 keto species, as a result of the ultrafast ESIPT, is very efficient because of the existence of two easily-approached keto S1/S0 conical intersections. In stark contrast to the S1 keto species, the decay of the S1 enol species is almostly blocked. The present theoretical study contributes valuable knowledge to the understanding of photochemistry of similar intramolecularly hydrogen-bonded molecular and biological systems. 展开更多
关键词 Excited state proton transfer PHOTOISOMERIZATION Conical intersection Ab initio PHOTOCHEMISTRY
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A Novel Approach for Warhead Fragments Velocity Measurement Based on Laser Screen
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作者 刘吉 赵冬娥 周汉昌 《Journal of Measurement Science and Instrumentation》 CAS 2011年第3期303-306,共4页
The velocity of warhead fragment is key criteria to determine its mutilation efficiency.We have designed an optoelectronic system to accurately measure the average velocity of warhead fragments.The apparatus including... The velocity of warhead fragment is key criteria to determine its mutilation efficiency.We have designed an optoelectronic system to accurately measure the average velocity of warhead fragments.The apparatus including two parallel laser screens spaced apart at a known fixed distance for providing time measurement start and stop signals.The large effective screen area is formed by laser source,retro-reflector and large area photo-diode with a central hole.Whenever a moving fragment interrupts two optical screen,the corresponding photometers senses the event,due to partial obscuration of the incident energy.Experiments have been performed to measure velocity of the different kinds of projectiles and fragments within various size and velocity ranges,including 7.62 mm bullet shooting experiments,prefabricated steel-ball exploding experiments.They were proved that the system is adequate to measure the velocity of larger than 5 mm,less than 1 000 m/s in the range,when fixed trajectory,test the velocity of the projectile average relative deviation is less than 4.21%.The system can perform satisfactorily with a lot of advantages such as larger effective light screen area,quick response speed,low uncertainty,strong repetition and reliability,etc. 展开更多
关键词 non-contact measurement velocity measurement laser screen retro-reflector
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Investigation of the pharmacokinetics and determination of certain cephalosporins in rabbit plasma by a kinetic spectrophotometric method with the aid of chemometrics 被引量:3
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作者 KOKOT Serge 《Science China Chemistry》 SCIE EI CAS 2011年第5期827-834,共8页
This paper describes a kinetic spectrophotometric method for simultaneous determination of three cephalosporin antibiotics,cephradine,cefaclor and cefixime,with the aid of chemometrics. The method relies on their oxid... This paper describes a kinetic spectrophotometric method for simultaneous determination of three cephalosporin antibiotics,cephradine,cefaclor and cefixime,with the aid of chemometrics. The method relies on their oxidation with KMnO4 to produce green manganate with different kinetic rates in alkaline medium. The proposed method was successfully applied to a pharmacokinetic study of three cephalosporin antibiotics in rabbit plasma via intravenous injections. The results indicated that the amount of cephradine,cefaclor and cefixime were reduced rapidly in rabbit blood,showing clear dose-dependency and the half-life of cefixime (160 min) was longer than those of cephradine (60 min) and cefaclor (60 min). 展开更多
关键词 PHARMACOKINETICS cephalosporin CEFACLOR CEFIXIME CEPHRADINE kinetic spectrophotometry CHEMOMETRICS
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Monitoring diesel engine parameters based on FBG probe
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作者 张豪 蒋奇 +1 位作者 王保岩 王俊杰 《Optoelectronics Letters》 EI 2016年第5期384-388,共5页
This paper proposes an unprecedented systematic approach for real-time monitoring the temperature and flow of diesel engine by using embedded fiber Bragg grating(FBG). By virtue of FBG's temperature effect, we des... This paper proposes an unprecedented systematic approach for real-time monitoring the temperature and flow of diesel engine by using embedded fiber Bragg grating(FBG). By virtue of FBG's temperature effect, we design a novel sensitive FBG temperature sensing probe to measure the temperature of cylinder head and inlet flow of diesel engine. We also establish the corresponding software platform for intuitive data analysis. The experimental and complementary simulation results simultaneously demonstrate that the FBG-based optical fiber technique possesses extraordinary reproducibility and sensitivity, which makes it feasible to monitor the temperature and inlet flow of diesel engine. Our work can provide an effective way to evaluate the thermal load of cylinder head in diesel engine. 展开更多
关键词 cylinder diesel unprecedented inlet intuitive grating Bragg monitor feasible complementary
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