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从形器到心性:略论苏轼文艺思想的转向
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作者 黄天飞 《乐山师范学院学报》 2023年第6期27-32,共6页
苏轼的文艺思想曾经历过一次从强调外在事功之“形器”层面,到侧重内在本体之“心性”层面的同时又内涵“形器”的辩证转化,这一过程呈现出了在当时历史语境下,苏轼以艺术为思考方式对现实人生出路的不懈探索。因而这种转向能够成为负... 苏轼的文艺思想曾经历过一次从强调外在事功之“形器”层面,到侧重内在本体之“心性”层面的同时又内涵“形器”的辩证转化,这一过程呈现出了在当时历史语境下,苏轼以艺术为思考方式对现实人生出路的不懈探索。因而这种转向能够成为负载独特思想意义的一种价值标尺,其主要指向包括在理论内容上突破了儒道的狭隘、在认知方式上从务虚转变为应物、在学术性格上蕴含经世致用品格。 展开更多
关键词 苏轼 “形器” “心性” 转向
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On the beginning of the Japanese Upper Paleolithic:A review of recent archaeological and anthropological evidence
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作者 Hiroyuki SATO Kazuki MORISAKI 《人类学学报》 CSSCI CSCD 北大核心 2024年第3期470-487,共18页
The beginning of the Japanese Upper Paleolithic has mainly been examined using two major models:the Middle Paleolithic evolutionary model within the archipelago and the continental Upper Paleolithic diffusion/migratio... The beginning of the Japanese Upper Paleolithic has mainly been examined using two major models:the Middle Paleolithic evolutionary model within the archipelago and the continental Upper Paleolithic diffusion/migration model.However,recent archeological data from Japan and nearby countries are challenging such simple models.This paper critically reviews previous chronology of the Japanese Paleolithic,including possible Lower and Middle Paleolithic(LP/MP),and attempts to show an alternative model of the beginning of the Japanese Upper Paleolithic.This paper suggests several possible specimens of LP/MP and recommends further geoarchaeological investigation to understand the reliability and cultural relationship between possible LP/MP specimens and the Early Upper Paleolithic(EUP).The start of the Japanese EUP is presently characterized by a flake industry with trapezoids and denticulates around 39-37 kaBP cal on Paleo-Honshu Island,which has partial resemblance with contemporary assemblages in China and the Korean Peninsula,although trapezoids are endemic only to the Japanese EUP and may have derived from the ancestral lithic tradition.Blade technology appeared earliest on Central Paleo-Honshu Island,about 1000 years later than the earliest flake technology.Although blade technology may have originated from the elongated flake technology of the previous period,the sudden simultaneous emergence implies that it diffused from the Korean Peninsula.This paper proposes that blade technology from the Korean Peninsula arrived on the northeastern Paleo-Honshu Island,including the Japan Sea coastal region of western Honshu,rather than the southwest,where flake technology long prospered,due to differences in ecological settings and adaptation strategies between the two regions. 展开更多
关键词 Japanese Archipelago Early Upper Paleolithic migration route TRAPEZOID denticulate blade technology
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Imaging simulation and analysis of attitude jitter effect on topographic mapping for lunar orbiter stereo optical cameras
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作者 CHEN Chen TONG Xiao-Hua +4 位作者 LIU Shi-Jie YE Zhen HUANG Chao-Wei WU Hao ZHANG Han 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2024年第5期722-730,共9页
The geometric accuracy of topographic mapping with high-resolution remote sensing images is inevita-bly affected by the orbiter attitude jitter.Therefore,it is necessary to conduct preliminary research on the stereo m... The geometric accuracy of topographic mapping with high-resolution remote sensing images is inevita-bly affected by the orbiter attitude jitter.Therefore,it is necessary to conduct preliminary research on the stereo mapping camera equipped on lunar orbiter before launching.In this work,an imaging simulation method consid-ering the attitude jitter is presented.The impact analysis of different attitude jitter on terrain undulation is conduct-ed by simulating jitter at three attitude angles,respectively.The proposed simulation method is based on the rigor-ous sensor model,using the lunar digital elevation model(DEM)and orthoimage as reference data.The orbit and attitude of the lunar stereo mapping camera are simulated while considering the attitude jitter.Two-dimensional simulated stereo images are generated according to the position and attitude of the orbiter in a given orbit.Experi-mental analyses were conducted by the DEM with the simulated stereo image.The simulation imaging results demonstrate that the proposed method can ensure imaging efficiency without losing the accuracy of topographic mapping.The effect of attitude jitter on the stereo mapping accuracy of the simulated images was analyzed through a DEM comparison. 展开更多
关键词 topographic mapping lunar orbiter stereo camera attitude jitter imaging simulation digital elevation model
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A Dual-polarized Frequency Selective Rasorber with a Tunable Transparent Band
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作者 SHI Tongtong ZHANG Xiaofa +4 位作者 WU Weiwei WANG Shaozhi XU Yixuan YAN Yuchen YAN Xiao 《电讯技术》 北大核心 2024年第10期1569-1575,共7页
A tunable dual polarization absorption-transmission-absorption(A-T-A)frequency selective absorbers(FSR)to address the issue of high insertion loss in current tunable FSRs is proposed.The lumped resistors are loaded on... A tunable dual polarization absorption-transmission-absorption(A-T-A)frequency selective absorbers(FSR)to address the issue of high insertion loss in current tunable FSRs is proposed.The lumped resistors are loaded onto the lossy layer to absorb electromagnetic waves within the absorption band.The varactor diodes are loaded onto another lossless layer to control the transmission frequency band of the FSR.Its equivalent circuit model is provided.The proposed tunable FSR can change the passband within the range of 14.5~15.5 GHz by changing the bias voltage applied to the lossless transmission layer,while maintaining insertion loss above-1.67 dB.The series resonant structure of the lossy layer generates bilateral absorption bands between 10.2~13.5 GHz and 17.2~22 GHz,with broadband reflection suppression ranging from 10.3 GHz to 22 GHz(70.7%).The prototype is manufactured,and the measured results have verified the simulation results. 展开更多
关键词 tunable frequency selective rasorber DUAL-POLARIZATION RCS reduction stealthy radomes
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A Fully Integrated CMOS Readout Circuit for Particle Detectors 被引量:2
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作者 张雅聪 陈中建 +2 位作者 鲁文高 赵宝瑛 吉利久 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第2期182-188,共7页
Novel schemes for a charge sensitive amplifier (CSA) and a CR-(RC), semi-Gaussian shaper in a fully integrated CMOS readout circuit for particle detectors are presented. The CSA is designed with poly-resistors as ... Novel schemes for a charge sensitive amplifier (CSA) and a CR-(RC), semi-Gaussian shaper in a fully integrated CMOS readout circuit for particle detectors are presented. The CSA is designed with poly-resistors as feedback components to reduce noise. Compared with conventional CSA, the input referred equivalent noise charge(ENC) is simulated to be reduced from 5036e to 2381e with a large detector capacitance of 150pF at the cost of 0.5V output swing loss. The CR-(RC),semi-Gaussian shaper uses MOS transistors in the triode region in series with poly-resistors to compensate process variation without much linearity reduction. 展开更多
关键词 charge sensitive amplifier SHAPER readout circuit noise optimization
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Inchworm locomotion gait for snakelike robot 被引量:1
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作者 孙洪 马培荪 王光荣 《Journal of Southeast University(English Edition)》 EI CAS 2007年第4期556-560,共5页
To establish a universal and easily controlled gait for practical use of snakelike robot movement, an inchworm locomotion gait model based on a serpenoid curve is presented. By analyzing the relations of two adjacent ... To establish a universal and easily controlled gait for practical use of snakelike robot movement, an inchworm locomotion gait model based on a serpenoid curve is presented. By analyzing the relations of two adjacent waves in the process of locomotion and doing an approximation of the serpenoid curve, the motion function of relative angles between two adjacent links and the absolute angles between each link and the baseline on the traveling curve are built. Two efficiency criterions of the gait are given as the energy loss function f and the unit displacement in one cycle dunit.Three parameters of the criterions affecting the efficiency of the gait ( the number of links that form the traveling wave n, the included angle between two adjacent links α, and the phase difference of adjacent included angles β) are discussed by simulations and experiments. The results show that f is insensitive to n; raising n increases dunit significantly; the maximum wave amplitude of α is a decreasing function of n; and increasing α reduces the displacement influence off when n is determined. The gait model is suitable for different inchworm locomotions of a snakelike robot whose traveling waves are formed by different numbers of identical links. A wave formed by more links or a greater relative angle between two adjacent links both lead to greater velocity of the movement. 展开更多
关键词 snakelike robot multilink inchworm locomotion gait efficiency criterion
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Morphological and Physiological Differences in the Floral Organs of Hosui Pear(Pyrus pyrifolia Nakai) between Normal and Returning Bloom during Late Autumn 被引量:1
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作者 张全军 钟必凤 +2 位作者 李文贵 邓家林 王建辉 《Agricultural Science & Technology》 CAS 2016年第1期15-18,共4页
[Objective] This study was conducted to investigate the morphological and physiological differences between the flowers opening spring and late autumn of Hosui Asian pear(Pyrus pyrifolia Nakai). [Method] Pear flower... [Objective] This study was conducted to investigate the morphological and physiological differences between the flowers opening spring and late autumn of Hosui Asian pear(Pyrus pyrifolia Nakai). [Method] Pear flowers were collected from normal bloom(NB) and returning bloom periods during late autumn in 2011-2013,respectively. The morphological and physiological indices including pollen number,germination rate, petal length, soluble protein content, soluble sugar content, amino acid content, pollen tube growth, fruiting characteristics of NB and RB flowers were detected and compared. [Result] The filament length and petal area of RB flowers were significantly smaller than those of NB flowers. The contents of soluble proteins, soluble sugars and amino acids of RB pollens were significantly smaller than those of NB flowers. In addition, the abortion rate of RB flowers was higher than that of NB flowers. [Conclusion] RB flowers had complete floral organs and were capable of pollination, but they were different from NB flowers in some morphological and physiological indices. 展开更多
关键词 Bud break Floral organ MORPHOLOGY PHYSIOLOGY
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Morphological and Anatomical Analyses of a Floral Organ Mutant in Rice 被引量:2
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作者 王文明 朱立煌 +2 位作者 谢戎 谢灿 金良 《Acta Botanica Sinica》 CSCD 2000年第4期379-382,共4页
A spontaneously occurred rice ( Oryza sativa L.) mutant characterized by homeotic conversions in glumes and stamens was found in the progeny of a breeding material. The mutant plant shows degenerated glumes and mor... A spontaneously occurred rice ( Oryza sativa L.) mutant characterized by homeotic conversions in glumes and stamens was found in the progeny of a breeding material. The mutant plant shows degenerated glumes and morphological transformation of stamens into pistils. A mutant floret consists of 1 to 3 completely developed pistils and 4 to 6 incomplete pistils with no ovary. Some pistilloid stamens still have filaments but tipped by bulged tissue and 0 to 3 stigmas. Three ovaries in a single floret were observed in its cross and longitudinal sections. When the mutant plants were pollinated with pollens from wild type plants, one or two naked seeds instead of a caryopsis could be produced in a single floret. The mutant is controlled by a single recessive gene since its F 1 hybrid plants were restored to wild type and 3∶1 ratio of wild type to mutant plants were observed in the progeny of heterozygotes. It seems that the mutant phenotype of the homeotic conversions in glumes and stamens is similar to that of the B loss_of_function mutants in Arabidopsis and Antirrhinum . 展开更多
关键词 RICE floral organ B loss_of_function MUTANT
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Floral Organogenesis of Titanotrichum oldhamii (Gesneriaceae) 被引量:2
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作者 潘开玉 李振宇 王印政 《Acta Botanica Sinica》 CSCD 2002年第8期895-902,共8页
Floral organogenesis of Titanotrichum oldhamii (Hemsl.) Soler., the only species in the genus and endemic to East Asia, was observed under SEM. We found that the development of calyx, corolla and androecium belong... Floral organogenesis of Titanotrichum oldhamii (Hemsl.) Soler., the only species in the genus and endemic to East Asia, was observed under SEM. We found that the development of calyx, corolla and androecium belongs to pentamerous pattern. They come respectively from primordia of calyx, corolla and androecium, and all differentiated from the flower primordium. The zygomorphism of corolla and androecium is derived from quicker growth of the upper lip of corolla and delay in development of the staminode. Initiation of sepal primordia and their development are not consistent in order; the order of initiation is from adaxial central primordium, abaxial two primordia and finally lateral two primordia, while the order of development is first adaxial central sepal, lateral two and finally abaxial two. Sepals are valvate in flower bud. Initiation of corolla lobe primordia and their development are consistent in order, i.e. first abaxial central lobe (central lobe of the lower lip), lateral two (lateral two lobes of the lower lip) and finally adaxial two (two lobes of the upper lip). The aestivation of corolla is imbricate, and the order from outside to inside is the central lobe of the lower lip, lateral two of the lower lip, and finally two of the upper lip or lateral two lobes of the lower lip, two of the upper lip and central one of the lower lip. Stamen primordia are alternate to the corolla lobe primordia, with the anterior two primordia later than the posterior two in initiation; staminode primordium is simultaneous with the posterior two in initiation, but smaller, and opposite to the adaxial carpel (upper lip of stigma). Compared to the patterns of floral organogenesis of Rehmannia (Scrophulariaceae), Whytockia and Rhynchoglossum (Gesneriaceae), the present authors found that the floral organogenesis is diverse and does not form two distinct patterns among these four genera. Based on the results we tend to consider that the conventional demarcation between the Scrophulariaceae and Gesneriaceae using number of ovary locules (two vs one) and placentation (axile vs parietal) is questionable. 展开更多
关键词 GESNERIACEAE Titanotrichum floral organogenesis
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Design and Fabrication of Ultracompact 3-dB MMI Coupler in Silicon-on-Insulator 被引量:1
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作者 严清峰 余金中 刘忠立 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第2期133-136,共4页
An ultracompact 3 dB coupler is designed and fabricated in silicon on insulator,based on 1×2 line tapered multimode interference (MMI) coupler.Comparing with the conventional straight MMI coupler,the device is... An ultracompact 3 dB coupler is designed and fabricated in silicon on insulator,based on 1×2 line tapered multimode interference (MMI) coupler.Comparing with the conventional straight MMI coupler,the device is ~40% shorter in length.The device exhibits uniformity of 1 3dB and excess loss of 2 5dB. 展开更多
关键词 multimode interference coupler line tapered waveguide silicon on insulator
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以类相动——《乐道——中国古典音乐哲学论稿》之一 被引量:4
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作者 陇菲 《星海音乐学院学报》 2002年第1期4-9,共6页
中国古典乐道,基于中国古典哲学“道、形、器”与“达、类、私”之基本范畴,揭示了“以类相动”、“比类成行”的音乐以其“形”之层面的、“法式”性质的“乐式”同行、同态于万事万物,“中”长宙大宇行运之“节”之行象艺术的本质... 中国古典乐道,基于中国古典哲学“道、形、器”与“达、类、私”之基本范畴,揭示了“以类相动”、“比类成行”的音乐以其“形”之层面的、“法式”性质的“乐式”同行、同态于万事万物,“中”长宙大宇行运之“节”之行象艺术的本质属性。墨子所谓“达而类私”,正是通过特殊的具象之私,上升到一般的抽象之达;正是通过一般的抽象之达,类归特殊的具象之私;正是通过特殊的具象之器,上升到一般的抽象之道;正是通过一般的抽象之道,形范特殊的具象之器。在这里,达是以类私的面目显现的,私是以达同的属类显现的;共相是以殊相的面目显现的,殊相是以共相的例案显现的;形而上之道是以形而下之器的面目显现的,形而下之器是以形而上之道的象征显现的。而在此种种界面之中,“形”乃是其“法式”性质的中介。就音乐艺术而言,形而上的乐道是以形而下的乐象之行态显现的,形而下的乐象是以形而上的乐道之象征显现的。而在此界面之中,形之层面的“乐式”,乃是“道”、“器”之间“法式”性质的中介。 展开更多
关键词 以类相动 比类成行 乐道 音乐哲学 中国古典音乐哲学 乐式 行象 中节 道、 达、类、私
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Gate Annealing of an Enhancement-Mode InGaP/AlGaAs/InGaAs PHEMT
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作者 黎明 张海英 +3 位作者 徐静波 李潇 刘亮 付晓君 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第8期1487-1490,共4页
For enhancement-mode InGaP/A1GaAs/InGaAs PHEMTs,gate annealing is conducted between gate structures of Ti/Pt/Au and Pt/Ti/Pt/Au. Comparison is made after thermal annealing and an optimum annealing process is ob- taine... For enhancement-mode InGaP/A1GaAs/InGaAs PHEMTs,gate annealing is conducted between gate structures of Ti/Pt/Au and Pt/Ti/Pt/Au. Comparison is made after thermal annealing and an optimum annealing process is ob- tained. Using the structure of Ti/Pt/Au, about a 200mV positive shift of threshold voltage is achieved by thermal annea- ling at 320℃ for 40min in N2 ambient. Finally, a stable and consistent enhancement-mode PHEMT is produced successfully with higher threshold voltage. 展开更多
关键词 ENHANCEMENT-MODE InGaP/A1GaAs/InGaAs PHEMT ANNEAL threshold voltage ring oscillator
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THREE-DIMENSIONAL TRAJECTORY OPTIMIZATION WITH DIRECT METHOD 被引量:1
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作者 沈春林 刘国刚 +1 位作者 吴文海 李丽荣 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2002年第2期118-122,共5页
The principle of direct method used in optimal control problem is introduced. Details of applying this method to flight trajectory generation are presented including calculation of velocity and controls histories. And... The principle of direct method used in optimal control problem is introduced. Details of applying this method to flight trajectory generation are presented including calculation of velocity and controls histories. And capabilities of flight and propulsion systems are considered also. Combined with digital terrain map technique, the direct method is applied to the three dimensional trajectory optimization for low altitude penetration, and simplex algorithm is used to solve the parameters in optimization. For the small number of parameters, the trajectory can be optimized in real time on board. 展开更多
关键词 direct optimization method trajectory optimization low altitude penetration simplex algorithm
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INFLUENCE AND CORRECTION OF SIGNAL SOURCE DISTORTION TO EVALUATION OF EFFECTIVE BITS OF WAVEFORM RECORDERS
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作者 梁志国 沈文 朱济杰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1997年第2期198-202,共5页
In most effective bits evaluation of waveform recorders, the prerequisite is that there is no signal source distortion, or the distortion can be neglected. But when the distortion can be neglected or how it affects th... In most effective bits evaluation of waveform recorders, the prerequisite is that there is no signal source distortion, or the distortion can be neglected. But when the distortion can be neglected or how it affects the evaluation when it can't be neglected it is not determined yet. In this paper, the influence of signal source distortion to the evaluation of the effective bits of waveform recorders is discussed, then, the correction method of the effective bits error caused by the distortion influence is given. Finally , the error limit of the effective bits is given and how to selecte the calibrator is introduced. In the end , some simulation results of the new method in test are described. 展开更多
关键词 waveform generators data acquisition EVALUATION effective bits waveform measurement
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Tunable photonic microwave generated by multi-wavelength Brillouin fiber laser
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作者 王如刚 张昕然 +1 位作者 赵力 张旭苹 《Journal of Southeast University(English Edition)》 EI CAS 2017年第1期22-26,共5页
Aimed at the problem of narrow tunability and low frequency microwave signal generated by the optical method,a novel approach to stabilizing the tunable photonic microwave generated by the multi-wavelength Brillouin f... Aimed at the problem of narrow tunability and low frequency microwave signal generated by the optical method,a novel approach to stabilizing the tunable photonic microwave generated by the multi-wavelength Brillouin fiber laser is proposed and is experimentally demonstrated.A singlelongitudinal-mode Brillouin fiber laser is designed,and by using the laser,a multi-wavelength Brillouin fiber laser with more than eleven orders of Stokes wave is observed.The wavelength spacing of the adjacent Stokes wave is 0.085 nm.If the Brillouin pump power is increased,the number of Stokes wave output can be further increased.The tunable microwave signals of 10.8 and 21.6 GHz are obtained by heterodyning the Rayleigh wave and Stokes wave of the multiwavelength Brillouin fiber laser.In the experiment,by tuning the pump wavelength and temperature of the gain fiber,microwave signals at different frequencies are generated.The tunable frequency range can be further expanded by using a temperature controller with a wider adjustment range,and the generated microwave signal exhibits high stability on frequency. 展开更多
关键词 Brillouin frequency shift ring laser MULTIWAVELENGTH microwave signal
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Welding of shape memory alloy to stainless steel for medical occluder 被引量:3
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作者 吕世雄 杨仲林 董红刚 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第1期156-160,共5页
Dissimilar metal joining between NiTi shape memory alloy(SMA) and stainless steel was conducted.A cluster of NiTi SMA wires were first joined with tungsten inert gas(TIG) welding process,then the NiTi SMA TIG weld... Dissimilar metal joining between NiTi shape memory alloy(SMA) and stainless steel was conducted.A cluster of NiTi SMA wires were first joined with tungsten inert gas(TIG) welding process,then the NiTi SMA TIG weld was welded to a stainless steel pipe with laser spot welding process.The microstructure of the welds was examined with an optical microscope and the elemental distribution in the welds was measured by electron probe microanalysis(EPMA).The results show that TiC compounds dispersively distribute in the NiTi SMA TIG weld.However,the amount of TiC compounds greatly decreases around the fusion boundary of the laser spot weld between the NiTi SMA and stainless steel.Mutual diffusion between NiTi shape memory alloy and stainless steel happen within a short distance near the fusion boundary,and intermetallic compounds such as Ni3Ti+(Fe,Ni)Ti appear around the fusion boundary. 展开更多
关键词 medical occluder NiTi alloy shape memory alloy stainless steel laser spot welding dissimilar metal joining Ni3Ti (Fe Ni)Ti
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Ridge Waveguide Electro-Optic Polymer Modulator with a New Kind of Corona Poled Crosslinkable Polyurethane 被引量:1
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作者 杨晓红 杜云 +2 位作者 殷爱民 石志文 吴荣汉 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第2期130-133,共4页
A polymer electro optic modulator has been fabricated with the functional layer acting as a kind of corona poled crosslinkable polyurethane. The three optical layers, namely waveguide, photolithography and oxygen are... A polymer electro optic modulator has been fabricated with the functional layer acting as a kind of corona poled crosslinkable polyurethane. The three optical layers, namely waveguide, photolithography and oxygen are fabricated by spin coating. With the Reactive Ion Etching method, the ridge of the waveguide is constructed. With light at 1 31μm being fiber coupled to waveguide, the mode and the modulation properties of these devices are demonstrated in a micron control system. 展开更多
关键词 MODULATOR polymer ridge waveguide
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Structure design and simulation of MEMS vibrating ring gyroscope 被引量:2
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作者 寇志伟 曹慧亮 +2 位作者 石云波 刘俊 唐军 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第1期78-83,共6页
MEMS gyroscope is a new inertial navigation sensor,which can measure the input angular rate of sensitive axis using Coriolis effect.Compared to the conventional gyroscope,it owns many unique advantages.A novel structu... MEMS gyroscope is a new inertial navigation sensor,which can measure the input angular rate of sensitive axis using Coriolis effect.Compared to the conventional gyroscope,it owns many unique advantages.A novel structure of vibrating ring gyroscope is proposed and the finite element model of the oscillator is established based on MEMS technology.Through the modal analysis,the natural frequency and mode shapes of the oscillator are obtained.By analyzing the effects of the structural parameters on the mode shapes and frequency of the harmonic oscillator,the optimal design parameters are got.The frequency difference between the operating mode and the other modes is greater than 1kHz after optimization,which can avoid the frequency coupling of the operating mode and other vibrating modes of the oscillator.The simulation results show that the performance parameters of the ring structure meet the design requirements and have obvious advantages. 展开更多
关键词 MEMS vibrating ring gyroscope inertial sensor angular rate solid wave gyroscope
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Material Growth and Device Fabrication of GaN-Based Blue-Violet Laser Diodes 被引量:1
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作者 杨辉 陈良惠 +16 位作者 张书明 种明 朱建军 赵德刚 叶小军 李德尧 刘宗顺 段俐宏 赵伟 王海 史永生 曹青 孙捷 陈俊 刘素英 金瑞琴 梁骏吾 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第2期414-417,共4页
Studies on first GaN-based blue-violet laser diodes(LDs) in China mainland are reported.High quality GaN materials as well as GaN-based quantum wells laser structures are grown by metal-organic chemical vapor depositi... Studies on first GaN-based blue-violet laser diodes(LDs) in China mainland are reported.High quality GaN materials as well as GaN-based quantum wells laser structures are grown by metal-organic chemical vapor deposition method.The X-ray double-crystal diffraction rocking curve measurements show the full-width half maximum of 180″ and 185″ for (0002) symmetric reflection and (10 12) skew reflection,respectively.A room temperature mobility of 850cm2/(V·s) is obtained for a 3μm thick GaN film.Gain guided and ridge geometry waveguide laser diodes are fabricated with cleaved facet mirrors at room temperature under pulse current injection.The lasing wavelength is 405 9nm.A threshold current density of 5kA/cm2 and an output light power over 100mW are obtained for ridge geometry waveguide laser diodes. 展开更多
关键词 metalorganic chemical vapor deposition GaN-based laser diodes multiple quantum wells ridge geometry structure threshold current density
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Fabrication of Windowed Very-Small-Aperture Laser Diodes
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作者 康香宁 徐云 +2 位作者 宋国峰 叶晓军 陈良惠 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第11期1145-1148,共4页
A windowed very small aperture laser (VSAL) source for use in high resolution near field optical data storage is fabricated.The windowed regions are introduced to avoid shorting the pn junction with metal coating a... A windowed very small aperture laser (VSAL) source for use in high resolution near field optical data storage is fabricated.The windowed regions are introduced to avoid shorting the pn junction with metal coating and suppress the COD effect.It facilitates producing VSAL by simplified technology and improves the laser performance.A VSAL with 400nm small aperture is demonstrated by focused ion beam (FIB) and the output power is 0 3mW at 31mA. 展开更多
关键词 very small aperture laser optical near field ridge waveguide focused ion beam
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