中国科学院机构知识库网格系统: 检索

浏览/检索结果: 共6条，第1-6条

帮助

条数/页：排序方式：
	Evaluating impacts of an extreme flood on a fish assemblage using hydroacoustics in a large reservoir of the Yangtze River basin, China 期刊论文 OAI收割 HYDROBIOLOGIA, 2019, 卷号: 841, 期号: 1, 页码: 31-43 作者: Huang, Geng; Wang, Qidong; Chen, Xiaohang; Godlewska, Malgorzata; Lian, Yuxi \| 收藏 \| 浏览/下载：168/0 \| 提交时间：2019/10/14 Fish stock Spatial distribution Hydrological changes Cage culture Habitat Target strength
	Hydroacoustic studies on the commercially important squid Sthenoteuthis oualaniensis in the South China Sea 期刊论文 OAI收割 FISHERIES RESEARCH, 2015, 卷号: 169, 页码: 45-51 作者: Zhang Jun; Chen Zuo-zhi; Chen Guo-bao; Zhang Peng; Qiu Yong-song 收藏 \| 浏览/下载：57/0 \| 提交时间：2016/11/02 Sthenoteuthis oualaniensis Squid Fishery acoustics Target strength South China Sea
	Hydroacoustic studies on the commercially important squid Sthenoteuthis oualaniensis in the South China Sea 期刊论文 OAI收割 FISHERIES RESEARCH, 2015, 卷号: 169, 页码: 45-51 作者: Zhang Jun; Chen Zuo-zhi; Chen Guo-bao; Zhang Peng; Qiu Yong-song 收藏 \| 浏览/下载：57/0 \| 提交时间：2016/11/02 Sthenoteuthis oualaniensis Squid Fishery acoustics Target strength South China Sea
	Surface shape optimization for the space membrane reflector (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Electronic and Mechanical Engineering and Information Technology, EMEIT 2011, August 12, 2011 - August 14, 2011, Harbin, China 作者: Zhang Y.; Zhang P. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 Space membrane reflector is very promised for optical quality application with the merits of ultra-lightweight and flexible. In order to improve the surface precision of membrane reflectors the formation and surface shape error of a membrane at uniform load are studied based on the henky-cambell equations of circular membrane. The ANSYS software is used to build an optimization model of membrane reflector surface shape in which the yield strength is the state variable the surface load on ten concentric annular regions of the mirror is the design variable and the minimum RMS between ideal surface and mirror surface is the target function. and the theoretical and experimental result show that RMS and PV of the optimized surfaces are reduced respectively than those before optimization. In a word this paper offers the theoretical and experimental basis of the polyimide membrane reflector. 2011 IEEE.
	Multi-focus image fusion algorithm based on adaptive PCNN and wavelet transform (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Imaging Detectors and Applications, May 24, 2011 - May 26, 2011, Beijing, China Wu Z.-G.; Wang M.-J.; Han G.-L. 收藏 \| 浏览/下载：77/0 \| 提交时间：2013/03/25 Being an efficient method of information fusion image fusion has been used in many fields such as machine vision medical diagnosis military applications and remote sensing.In this paper Pulse Coupled Neural Network (PCNN) is introduced in this research field for its interesting properties in image processing including segmentation target recognition et al. and a novel algorithm based on PCNN and Wavelet Transform for Multi-focus image fusion is proposed. First the two original images are decomposed by wavelet transform. Then based on the PCNN a fusion rule in the Wavelet domain is given. This algorithm uses the wavelet coefficient in each frequency domain as the linking strength so that its value can be chosen adaptively. Wavelet coefficients map to the range of image gray-scale. The output threshold function attenuates to minimum gray over time. Then all pixels of image get the ignition. So the output of PCNN in each iteration time is ignition wavelet coefficients of threshold strength in different time. At this moment the sequences of ignition of wavelet coefficients represent ignition timing of each neuron. The ignition timing of PCNN in each neuron is mapped to corresponding image gray-scale range which is a picture of ignition timing mapping. Then it can judge the targets in the neuron are obvious features or not obvious. The fusion coefficients are decided by the compare-selection operator with the firing time gradient maps and the fusion image is reconstructed by wavelet inverse transform. Furthermore by this algorithm the threshold adjusting constant is estimated by appointed iteration number. Furthermore In order to sufficient reflect order of the firing time the threshold adjusting constant is estimated by appointed iteration number. So after the iteration achieved each of the wavelet coefficient is activated. In order to verify the effectiveness of proposed rules the experiments upon Multi-focus image are done. Moreover comparative results of evaluating fusion quality are listed. The experimental results show that the method can effectively enhance the edge details and improve the spatial resolution of the image. 2011 SPIE.
	Characteristic and mechanism of damaging of ultra-high strength steel target penetrated by shaped charged jet 期刊论文 OAI收割 ACTA METALLURGICA SINICA, 2002, 卷号: 38, 期号: 11, 页码: 1210-1214 作者: Yin, ZX; Ma, CX; Li, SX; Liu, YL \| 收藏 \| 浏览/下载：9/0 \| 提交时间：2021/02/02 shaped charged jet penetration ultra-high strength steel target adiabatic shearing bands