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	Chromatic analysis of harmonic Fresnel lenses by FDTD and angular spectrum methods 期刊论文 OAI收割 Applied Optics, 2018, 卷号: 57, 期号: 19, 页码: 5281-5287 作者: Yang, Jianming; Twardowski, Patrice; Gerard, Philippe; Yu, Wenhui; Fontaine, Joel \| 收藏 \| 浏览/下载：25/0 \| 提交时间：2019/09/17 Time domain analysis Angle measurement Diffraction efficiency Efficiency Finite difference time domain method Full width at half maximum Harmonic analysis Optical instrument lenses Refractive index Spectrum analysis
	Visually Dynamic Presentation of Proofs in Plane Geometry Part 2. Automated Generation of Visually Dynamic Presentations with the Full-Angle Method and the Deductive Database Method 期刊论文 OAI收割 JOURNAL OF AUTOMATED REASONING, 2010, 卷号: 45, 期号: 3, 页码: 243-266 作者: Ye, Zheng; Chou, Shang-Ching; Gao, Xiao-Shan \| 收藏 \| 浏览/下载：20/0 \| 提交时间：2018/07/30 Geometry theorem proving Proof with hierarchical structures Visually dynamic presentation of proof Dynamic geometry Full-angle Deductive database Fixpoint Unordered geometry Hilbert geometry Tarski geometry
	A study on atmospheric turbulence effects in full-optical free-space communication systems (EI CONFERENCE) 会议论文 OAI收割 2010 6th International Conference on Wireless Communications, Networking and Mobile Computing, WiCOM 2010, September 23, 2010 - September 25, 2010, Chengdu, China 作者: Liu P. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 Next generation free-space optical communication systems have used fiber-optic technology as the seamless connection between free-space and optical fiber. The full-optical free-space optical communication systems use optical fiber as the receiver to get faster communication speed. The atmospheric turbulence deeply influenced on the optical wave propagated in terrestrial application. As the active receiving area of the full-optical free-space optical communication systems is very small it is important to research on the atmospheric turbulence effects on the full-optical free-space optical communication system. In this paper we discuss about both the turbulence-induced intensity fluctuations and the angle-of-arrival effects in full-optical free-space optical communication systems which are used in a few kilometers communication. We gave the numerical results of the atmosphere turbulence effects on the free-space optical communication systems. In order to minimize the atmospheric turbulence influence on the full-optical free-space optical communications system we also investigate the use of fine tracking system in the communication system. We have set up a full-optical free-space communication system in Tokyo and received useful data from the experiment. We compared the receiving power of the experiment when the fine tracking system is On and Off. From the experiment results we can see that the fine tracking system effectively mitigates the atmospheric turbulence and increases the receiving power of the communication system. 2010 IEEE.
	Simulations and experimental studies of diffuser/nozzle pumps (EI CONFERENCE) 会议论文 OAI收割 4th International Symposium on Precision Mechanical Measurements, August 25, 2008 - August 29, 2009, Hefei/Jiuhua Mountain, Anhui, China 作者: Li W.; Li W. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 An investigation of diffuser/nozzle micropumps is presented. Numerical simulations are done using CFD program ANSYS/Flotran. The simulations show when the opening angel is small the flow in the diffuser/nozzle is steady the mass flow is increasing with the adding opening angle. But when the opening angel continues increasing the pressure grads will be bigger than zero. It means that the static pressure is gradually going up along the diverging direction. The fluid near the wall stops flowing because the velocity decreases rapidly and the dynamic pressure is not big enough to overcome the increasing of the static pressure. Finally the fluid flows reversely from the backward position of higher pressure area this makes the separation flow of fluid the diffuser is full of reverse fluid. And this results in the dropping of mass flow at last. The simulations also show that the performance of diffuser with a round inlet is better than that with a sharp inlet. The mass flow of micropumps with different opening angles different inlets are measured. The experimental results agree well with the simulations. 2008 SPIE.
	The full hemisphere integrating measurement of the reflectance of black cavity (EI CONFERENCE) 会议论文 OAI收割 ICO20: Illumination, Radiation, and Color Technologies, August 21, 2005 - August 26, 2005, Changchun, China 作者: Wang Y.; Yu B.; Wang Y.; Wang Y.; Wang Y. 收藏 \| 浏览/下载：18/0 \| 提交时间：2013/03/25 The conical black cavities are used in the Solar Irradiance Absolute Radiometers (SIARs) of the solar constant monitor aboard on the SZ spaceship and of the Solar Total Irradiance Monitor (STIM) aboard on sun-synchronous polar orbit weather satellites. A low reflectance measurement instrument which is used for making the integrating measurement on the reflectance of the conical black cavity in a high precision within the full hemisphere (include the entrance of the Ulbrichtsphere) has been constructed. The characteristic of the instrument is the employment of a semi-transparent mirror which is mounted in an inclination angle of 45 degrees in front of the entrance of the Ulbrichtsphere. The incident beam is reflected to the black cavity or white board by the semi-transparent mirror. A portion of those which is made diffused reflection through the black cavity or white board is measured by the detector located in the side face of the Ulbrichtsphere and the other portion which is reflected to the entrance is measured by the other detector after passing through the semi-transparent mirror and then being focused on by an ellipsoidal mirror. The two measurement data are added up to get the integrating reflectance within full hemisphere. The presentation and verification on the measurement result of the reflectance of the black cavity and its precision are described in this article. The absolute accuracy can reach 0.012%.
	High-power InGaAs/GaAs VCSEL's two-dimension arrays (EI CONFERENCE) 会议论文 OAI收割 ICO20: Lasers and Laser Technologies, August 21, 2005 - August 26, 2005, Changchun, China 作者: Liu Y.; Wang L.-J.; Wang L.-J.; Liu Y.; Liu Y. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 Selectively oxidized InGaAs/GaAs vertical -cavity surface-emitting lasers (VCSEL) array at an emission wavelength of 980nm was reported. A 16 elements array with 200m aperture size (250m center spacing) of individual elements shows a CW output power of 1.21 W at room temperature resulting in 1 KW/cm2 average optical power density. The device threshold current is 1.32A The lasing peak wavelength is 981.9 nm the full width at half-maximum is 0.7 nm and the far-field divergence angle is about 17.The characteristics of a single device with a active region diameter of 800m is compared with that of a 2-D array with active region diameter of individual clement of 200m. These two kinds of devices have the same total lasing area. At the same current injection the single device has a higher threshold and a higher output power than the array. The red shift of single device is more obvious than that of the array's.