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	典型城镇污水处理工艺提质增效的数值模拟优化与应用学位论文 OAI收割北京: 中国科学院生态环境研究中心, 2020 作者: 柳蒙蒙 \| 收藏 \| 浏览/下载：95/0 \| 提交时间：2021/07/06 膜生物反应器 Membrane Mioreactor, Computational Fluid Dynamics Activated Sludge Model Improve Quality And Efficiency Wastewater Treatment Plant 计算流体力学活性污泥模型提质增效污水处理厂
	Study on spectrograph for ionosphere: A broadband imaging instrument prototype for far-ultraviolet (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China 作者: Wang S.-R.; Lin G.-Y.; Yu L. 收藏 \| 浏览/下载：35/0 \| 提交时间：2013/03/25 Current research on space-based exploration for the ionosphere needs more advanced technologies. Because the spectral signals in the ionosphere distributing basically in the far-ultraviolet waveband are very weak. Usual spectrometer structures and detectors such as CCD can't receive enough information. Based on this principle of atmospheric sounding the imaging spectrometer prototype for ionosphere detection application was designed to solve the problem. This prototype consists of the telescope and the imaging spectrometer. The simple structure and small number of mirrors can help higher transmission efficiency be achieved and weak signals detection be implemented. The telescope is an off-axis parabolic mirror and the spectrometer is a modified Czerny-Turner spectral imaging system. Modified Czerny-Turner spectrometer contains a spherical mirror a fixed plane grating and a toroidal mirror. By adjusting the incident angle to the collimating mirror and using toroidal mirror coma and astigmatism were corrected well. We also optimize distances between the grating to the focusing mirror and the focusing mirror to the image plane to improve disadvantages of traditional Czerny-Turner structure. Designed results demonstrate that aberrations are substantially corrected and high image quality can be obtained in broad waveband. The photon counting Wedge-Strip-Anode detector with micro-channel planes as the receiving plane is accepted for the instrument prototype. The other photon counting 2-D detector responding well for weak light such as Cross-Delay line detector and MAMA detector can also be used for detection. The calibration and performances testing system is made of a vacuum system a deuterium lamp a monochrometer and the instrument prototype. Results obtained from the experiment show that the spectral resolution is 2.4 nm and the spatial resolution is 80 m. The other calibration experiments are running. The technology of the spectrometer prototype is important for the research and applications of ionosphere remote sensing. 2011 SPIE.
	CCD performance model and noise control (EI CONFERENCE) 会议论文 OAI收割 3rd International Conference on Image Analysis and Signal Processing, IASP 2011, October 21, 2011 - October 23, 2011, Wuhan, China 作者: Sun H.; Wang Z.; Wang Z.; Sun H. 收藏 \| 浏览/下载：17/0 \| 提交时间：2013/03/25 In this paper we describe the performance models of a Charge Coupling Device (CCD) and discuss the issues in the CCD image sensor that deteriorates the CCD imaging performance. We analyze the cause of noise in the CCD imaging sensor and provide methods to control the CCD noise to improve the CCD's imaging quality. Some simulation results are presented in the paper to show the efficiency of the noise control methods. 2011 IEEE.
	High power diode laser with beam coupling (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.; Liu Y.; Wang L.; Liu Y.; Liu Y. 收藏 \| 浏览/下载：59/0 \| 提交时间：2013/03/25 As the increasing applications of the semiconductor lasers in the laser processing the single 2-D stack optic-power density has not satisfied the actual requirements. It demands to couple several diode laser stack beams to one to improve the brightness and it becomes the central issue to adopt the appropriate beam coupling technology which would offer high quality and high efficiency. In this paper it mainly introduces the beam shaping and the technology of spatial coupling polarization coupling and wavelength coupling. The coupling key elements are presented and indicated. Finally the development of the diode laser on beam coupling in our country fell behind through analyzing the statement of the world. Our lab is studying on polarization coupling and wavelength coupling. We gain some results by phase which the polarization coupling efficiency can achieve 90% for two LD stacks with seven bars whose luminous wavelength is 975nm and980nm.By two 808nm diode laser coupling the efficiency of 60% can be achieved after focusing to the beam size of 22mm2. 2008 SPIE.
	Algorithm research of flexible graphplan based on heuristic (EI CONFERENCE) 会议论文 OAI收割 9th International Conference for Young Computer Scientists, ICYCS 2008, November 18, 2008 - November 21, 2008, Zhang Jia Jie, Hunan, China 作者: Xu S.; Wang X.; Wang X.; Wang X.; Sun Y. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 Classic Graphplan has too much restriction on capturing the full subtlety of many real problems. Flexible Graphplan is defined which supports the soft constraints often found in reality. Heuristic concept is introduced to the process of plan extraction in flexible graphplan in order to improve the efficiency of plan extraction and the quality of plan. A novel algorithm using the new heuristic function which is applied by improved sum mutex heuristic to deal with planning problems is proposed. Sum mutex heuristic which is in common use as heuristic function takes into account only static propositional mutexes and ignores the mutexes of actions. The performance of the new algorithm on many benchmark problems is remarkably robust. It can solve many planning problems which can't be solved by the heuristic state space search planning system using sum mutex heuristic. 2008 IEEE.
	High power VCSEL device with periodic gain active region (EI CONFERENCE) 会议论文 OAI收割 Optoelectronic Materials and Devices II, November 2, 2007 - November 5, 2007, Wuhan, China 作者: Zhang Y.; Liu Y.; Liu Y.; Liu Y.; Qin L. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 High power vertical cavity surface emitting lasers with large aperture have been fabricated through improving passivation lateral oxidation and heat dissipation techniques. Different from conventional three quantum well structure a periodic gain active region with nine quantum wells was incorporated into the VCSEL structure with which high efficiency and high power operation were expected. The nine quantum wells were divided into three groups with each of them located at the antinodes of the cavity to enhance the coupling between the optical field and the gain region. Large aperture and bottom-emitting configuration was used to improve the beam quality and the heat dissipation. A maximum output power of 1.4W was demonstrated at CW operation for a 400m-diameter device. The lasing wavelength shifted to 995.5nm with a FWHM of 2nm at a current of 4.8A due to the internal heating and the absence of active water cooling. A ring-shape farfield pattern was induced by the non-homogeneous lateral current distribution in large diameter device. The light intensity at the center of the ring increased with increasing current. A symmetric round light spot at the center and single transverse mode operation with a divergence angle of 16 were observed with current beyond 4.8A.
	Optical fiber transmission of Q-switdied Nd:YAG pulses of 10MW peak power: Mechanism of damage to the fiber (EI CONFERENCE) 会议论文 OAI收割 2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies - Advanced Optical Manufacturing and Testing Technologies, November 2, 2005 - November 5, 2005, Xian, China 作者: Wang L.; Zhang Y.; Chen W.; Tang Y.; Wang L. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 This paper presents theoretical analysis and experiment results of four different fibers transmitting 10MW peak power Nd: YAG laser pulse. The main factors limiting to optical fiber transmission of high power laser pulse is pointed including air breakdown at focus area and surface damage of optical fiber. The theory of air breakdown and the fiber coupling conditions is described briefly. The results of study to the transmission properties and damage conditions are presented on the basis of four different types of optical fibers. The results of the experiments are further analyzed in the aspects of transmitting efficiency air breakdown and surface damage. The local and foreign optical fibers with plastic-cladding and silica-cladding and step- index and graded- index fibers are tested separately in the experiments. The experiments showed that the imported fibers are able to transmit up to 10MW peak power laser pulse with no any visible damage while energy density at the fiber output end surface is 3.54GW/cm2. For local fibers damage on the input surface of both plastic-cladding and silica-cladding step-index fibers was found obviously. The column damage to the graded index fiber was also found and investigated in the research. Damage mechanisms of fiber at high peak power laser pulses are summarized. High quality finishing of fiber end surface will improve damage threshold tremendously. The conclusion of the study is that transmitting Q-switched Nd:YAG pulses of 10MW peak power is feasible for the domestically made fibers if their end surfaces are properly processed.