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烟台牟平海洋牧场季节性低氧对大型底栖动物群落的生态效应 期刊论文  OAI收割
生物多样性, 2019, 卷号: 27, 期号: 2, 页码: 200-210
作者:  
李宝泉
  |  收藏  |  浏览/下载:21/0  |  提交时间:2020/06/17
低氧  群落结构  群落恢复  敏感种  机会种  hypoxia  community structure  community recovery  sensitive species  opportunistic species  Hypoxia is a common phenomenon in the world's oceans, especially in the shallow waters of coastal zones. Rates of hypoxia are increasing due to global climatic changes and anthropogenic activities. Hypoxia can cause mass mortality of marine animals and can have severe negative impacts on marine ecosystems. To better understand the effects of hypoxia on macrobenthic communities, a survey was carried out in the Muping Marine Ranch (Yantai) during June, August and September of 2016. Results showed that seasonal hypoxia led to changes in benthic community structure, especially in terms of species composition and dominant species. The dominant species were Polychaeta Lumbrinereis latreilli, Sternaspis scutata and Mollusca Endopleura lubrica in summer. The opportunistic species Lumbrinereis latreilli increased, whereas, sensitive species such as Leptomya minuta, Glycera chirori, Upogebia major, Pontocrates altamarimus, Eriopisella sechellensis decreased during the hypoxic period of August. Hypoxia also reduced biodiversity indices. The effect of hypoxia on abundance and biomass were not significant, mainly because of the increase in the opportunistic Lumbrinereis latreilli, which counteracted the decline in abundance and biomass of other species. Individual physiological tolerance to hypoxia was different among species. Lumbrinereis latreilli showed higher tolerance to hypoxia in dissolved oxygen (DO) = 1.0 mg/L compared to other species. Some sensitive species, such as Leptomya minuta, Upogebia major, Pontocrates altamarimus and Eriopisella sechellensis showed lower tolerance when DO < 2.5 mg/L. When DO increased to 2.5 mg/L, the macrobenthic community start to recover gradually. The recovery extent and time needed were closely related to the degree of seasonal hypoxia.  
Study on ultra-light secondary baffle for coaxial two-mirror telescope (EI CONFERENCE) 会议论文  OAI收割
2012 9th IEEE International Conference on Mechatronics and Automation, ICMA 2012, August 5, 2012 - August 8, 2012, Chengdu, China
作者:  
Zhang L.;  Zhang L.
收藏  |  浏览/下载:61/0  |  提交时间:2013/03/25
The coaxial two-mirror telescope consists of two mirrors facing each other. Classical two-mirror arrangements are Gregorian and Cassegrain. These systems are usually applied to space telescopes and often have optical baffles to prevent stray light from entering the focal plane. The optical baffles consist of concentric rings suspended between the secondary and the primary mirror. The secondary baffle for a large two-mirror optical system is designed and analyzed in this paper. According to mission of a telescope  the structure should have high stiffness and high reliability and light weight. Compared with invar  aluminum alloy and titanium alloy  carbon fiber composite is currently the best material in terms of weight-to-strength ratio. It also has advantages of high temperature tolerance and low thermal expansion. So carbon fiber composite is chosen as material to meet requirements of the coaxial telescope. In this paper  optimization method based on finite element analysis (FEA) is used for design the secondary baffle. Minimum weight of the baffle is chosen as an objective function. Thicknesses of former tube and vanes are chosen as variables. Analysis results show that the designed secondary baffle has maximum diameter of 180mm  total length of 120mm and weighs 142g. And its fundamental frequency reaches 651Hz. Therefore the baffle has many advantages  such as ultra-light weight  high stiffness and dimensional stability  etc. The optimization method and the baffle design can be helpful to other coaxial telescopes  such as Cassegrain  Gregorian and their subdivisions. 2012 IEEE.  
An accuracy requirement analysis for LED brightness and color correction system (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Transportation, Mechanical, and Electrical Engineering, TMEE 2011, December 16, 2011 - December 18, 2011, Changchun, China
作者:  
Wang R.
收藏  |  浏览/下载:63/0  |  提交时间:2013/03/25
Brightness and color correction system is working for the color uniform problem of LED display. The correction system can improve LED display's quality greatly. The accuracy of the LED system must consider the accuracy requirements of the color correction system. This paper analyze the accuracy requirements from two aspects. One is that the accuracy requirements should consider the chromatic tolerance for the human eyes  the other one is that the accuracy requirements should be associated with the precision of measuring equipment. This paper discuss the accuracy requirement with the CIE1976LUV as a color space to meet the chromatic tolerance of the human eyes  and also give an explanation on how the accuracy of the measuring equipment affect the the correction system. Then this paper give a method to ensure the accuracy requirement for the correction system of a LED display. 2011 IEEE.  
The optical design of cubic phase plate testing system (EI CONFERENCE) 会议论文  OAI收割
2011 Symposium on Photonics and Optoelectronics, SOPO 2011, May 16, 2011 - May 18, 2011, Wuhan, China
作者:  
Zhang X.;  Zhang X.;  Zhang X.;  Zhang Y.
收藏  |  浏览/下载:19/0  |  提交时间:2013/03/25
Computer-generated holograms (CGH) have been widely used for years in optical testing of aspheric surfaces in combination with Fizeau interferometers. With the development of diffraction optics  computer technology  and micro-processing technology  the accuracy of the CGH testing can achieve a hundredth of a wave  and the cost is reduced greatly. CGH is capable of producing an optical wavefront with any desired shape. So it is fascinating and will have good prospects to test free-form surfaces using CGH. As the CGH can create any wavefront shape  it can also be used in unsymmetrical aspherical surfaces testing. Taking the cubic surface as an example  this paper gives a method to test unsymmetrical surfaces. This paper gives the design to test a cubic surface. And the separation of the diffraction orders and the binary process of the continuous CGH phase function are discussed in detail. The alignment tolerance of the test system and the CGH fabrication tolerance are analyzed. We also present an idea using a CGH and two spherical lenses as null lens to test the cubic surface when the surface deviation is great. 2011 IEEE.  
Study on dynamic imaging on TDI CCD optical remote sensor of push-broom technology (EI CONFERENCE) 会议论文  OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China
作者:  
Liu L.;  Ren J.-Y.;  Liu L.;  Gao M.-H.
收藏  |  浏览/下载:22/0  |  提交时间:2013/03/25
A set special detecting system is proposed based on TDICCD push-broom technology applying in dynamic imaging detecting experiment of space optics remote sensor. In the system  In the course of detecting  push-broom movement of the satellite is simulated through using double supporting U structure precision rotary platform with remote sensor by angular speed 0.555/s  regard Nyquist frequency target as detecting aim  within the range of 5 and control precision on steady speed achieves 0.3%  in order to solve matching uncertainty between the CCD pixel and the vertical target strip image when the remote sensor does push-broom  make matching simplify  enhance the measurement result the accuracy. So the tolerance a/n arithmetic progression gap target strip is joined in each group of rectangular vertical group target strip. The remote sensor obtains in vertical  the level and 45 the direction 0 fields of view  0.86 the field of view Nyquist frequency target strip image after detected  a group target strip which can precision matching to TDICCD pixel at least can be obtained through analysis and dealing with 0.86 field of view's target strip image. The experiment not only verifies the detecting system's feasibility but simultaneously verifies whether to have the high quality dynamic imaging quality when TDICCD push-broom technology is adopted on the remote sensor developed. 2010 Copyright SPIE - The International Society for Optical Engineering.  
Modeling and analysis of dialyte-lens auto-focusing technology for theodolite (EI CONFERENCE) 会议论文  OAI收割
2008 International Conference on Optical Instruments and Technology: Optoelectronic Measurement Technology and Applications, November 16, 2008 - November 19, 2008, Beijing, China
Wu L.-T.; Qiao Y.-F.; Wu D.-K.; Cai S.
收藏  |  浏览/下载:24/0  |  提交时间:2013/03/25
In order to realize real-time auto-focusing for theodolite  lens-apart method was designed with the corresponding math model built and analyzed. An Object beam splitted after the first image surface of the theodolite traveled through two dialyte lens and then was imaged on CCD. The distance between two spots when exactly focused was set as the calibration value  and the relationship between defocus distance and spot offset was given. The influence of tracking center shift and divergence angle etc. on focusing accuracy was analyzed. Compared with the traditional focusing method  this scheme has a higher accuracy  faster calculation  higher tolerance for environment temperature and a simpler construction. The experiment result exhibited a resolution higher than 0.056mm  which shows a bright engineering application prospect for this method. 2009 SPIE.  
Arsenic accumulation by the aquatic fern Azolla: Comparison of arsenate uptake, speciation and efflux by A. caroliniana and A. filiculoides 期刊论文  OAI收割
ENVIRONMENTAL POLLUTION, 2008, 卷号: 156, 期号: 3, 页码: 1149-1155
作者:  
Xu, Guo-Zhong;  Lin, Ai-Jun;  Zhao, Fang-Jie;  Zhang, Xin;  Zhu, Yong-Guan
  |  收藏  |  浏览/下载:59/0  |  提交时间:2015/08/21
The effect on tolerance distributing of an off-axis three mirror anastigmatic optical system with wavefront coding technology (EI CONFERENCE) 会议论文  OAI收割
Optical System Alignment and Tolerancing II, August 10, 2008 - August 11, 2008, San Diego, CA, United states
作者:  
Yan F.;  Zhang X.-J.;  Yan F.
收藏  |  浏览/下载:35/0  |  提交时间:2013/03/25
The wavefront coding technology is known as a system-level technology which can extend the depth of focus of optical system by innovative optical design and image restoration. This technology can control misfocus related aberrations including misfocus  astigmatism  and Petzval curvature  temperature-related misfocus in digital imaging systems. It can also help optical system tolerate more residual error in optical manufacturing and alignment besides misfocus. The brief introduction of wavefront coding technology and the wavefront coded TMA system under research is presented respectively in part 1 and part 2. The "MTF similarity" is defined to describe the relationship among MTF at different position or different fields in the third part. It is also shown in this part that the MTF similarity of wavefront coded system is much higher than the normal system within a large range. In part 4 comparison between the origin system and the new system with wavefront coding technology is provided after multiple errors are introduced  from which it can be observed that the system with wavefront coding technology can tolerate much bigger error than origin system. The error tolerance is re-distributed according to a new criterion based on MTF similarity. If the MTF similarity is less than a certain value  it can be regarded that the system can tolerate the residual error. The new error tolerance is displayed and it is shown that the wavefront coding technology can also loosen the error distributing besides extended the depth of focus.  
Central hole effect on Whispering-Gallery-Mode of triangular lattice photonic crystal microcavity (EI CONFERENCE) 会议论文  OAI收割
Optoelectronic Materials and Devices III, October 27, 2008 - October 30, 2008, Hangzhou, China
作者:  
Zhang Y.;  Wang L.;  Wang L.;  Wang L.;  Wang Z.
收藏  |  浏览/下载:25/0  |  提交时间:2013/03/25