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	Effect of providing free glasses on children's educational outcomes in China: cluster randomized controlled trial SCI/SSCI论文 OAI收割 2014 Ma X. C.; Zhou Z. Q.; Yi H. M.; Pang X. P.; Shi Y. J.; Chen Q. Y.; Meltzer M. E.; Le Cessie S.; He M. G.; Rozelle S.; Liu Y. Z.; Congdon N. 收藏 \| 浏览/下载：76/0 \| 提交时间：2014/12/24 pediatric-refractive-error visual impairment school-children rural china southern china see-well myopia prevalence vision
	The reflector bracket mirror structure optimization and design of the IR warring system (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Advanced Engineering Materials and Technology, AEMT 2011, July 29, 2011 - July 31, 2011, Sanya, China 作者: Wang B.; Wang B. 收藏 \| 浏览/下载：21/0 \| 提交时间：2013/03/25 This paper introduced a kind of reflector mirror support structure of IRST system. Thescanning reflector mirror support frame material is Ly2 aluminum under the principle of the suited ofmaterial expanding quotient. The support form of the reflector was talked and the system bracketstructure was designed following the requests of the certain complex IRST. The bracket wasoptimized and analyzed under the best structure quality and the least moment of inertia and thebellowing of bracket plane thickness mode frequency restriction and deadweight restriction. Fromthe result we can see that the bracket mass can reduce from 0.73kg to 0.49kg and the moment ofinertia can reduce from 0.0109kg2 to 0.0056 kg2 under the first precondition of the structure modefrequency being low and the biggest transmogrification being teeny. The base frequency and intensionof the complex IRST system can be indicated well after the finite element analysis static checking. (2011) Trans Tech Publications Switzerland.
	Temperature characteristics of several familiar diode lasers with broad area (EI CONFERENCE) 会议论文 OAI收割 Optoelectronic Materials and Devices III, October 27, 2008 - October 30, 2008, Hangzhou, China 作者: Wang L.; Qin L.; Wang L.; Wang L. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 Temperature characteristics of several familiar high power diode lasers with broad area whose wavelength was separately 808 nm 810 nm 940 nm and 980 nm were analyzed. In order to see the effect the change of the quantum well structure on the characteristic temperatures different structures were attempted. For the 808 nm structure we tried different barrier thicknesses. For the 810 nm structure different cavity lengths were attempted. And we studied the 940 nm and 980 nm also. In this paper the widths of these devices were all 100 m. Characteristic temperatures of these devices were calculated. The appropriate structure was available for different application. 2008 SPIE.
	The spectral feature analysis of semiconductor thin disk laser (EI CONFERENCE) 会议论文 OAI收割 Optoelectronic Materials and Devices II, November 2, 2007 - November 5, 2007, Wuhan, China 作者: Li J.; Wang L.-J.; Wang L.-J.; Ning Y.-Q.; Li J. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 The semiconductor thin disk laser is a new type of semiconductor laser. This work gives the basic operation function of semiconductor disk laser and analyses the heat effect by the experimentally measured photoluminescence spectrum of the laser chip at different pump power and different temperature. We can see that: with increasing pump power the thermal effects of the gain material becomes seriously and causes the saturation of carrier lifetime so the electron-hole pair created in the absorbtion layer have no enough time to rate to one of the wells and the non-radiative recombination happens in the barrier. When the thermal effects becomes stronger the chip will not lasing. This phenomenon is from the smaller energy offset between barrier and quantum well. We optimize the original structure design and experimental technology. A non-absorbing AlGaAs layer who is transparent to the pumping and laser wavelength is added to confine the carriers in the quantum wells. At the same time a DBR with double reflecting band is induced to improve the absorbing efficiency of the pumping light. The single QW is replaced by the three narrow QWs This three QWs structure can add the quantum state of QW increase the recombination probability of carriers in the QWs and reduce the heat effect. The chemical etch equipment is also improved to control the surface unevenness to be within 50 nm.