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Efficient and robust large-scale structure-from-motion via track selection and camera prioritization 期刊论文  OAI收割
ISPRS JOURNAL OF PHOTOGRAMMETRY AND REMOTE SENSING, 2019, 卷号: 156, 页码: 202-214
作者:  
Cui, Hainan;  Shen, Shuhan;  Gao, Wei;  Liu, Hongmin;  Wang, Zhiheng
  |  收藏  |  浏览/下载:87/0  |  提交时间:2019/09/30
食用蔬菜能吸收和积累微塑料 期刊论文  OAI收割
科学通报, 2019, 卷号: 64, 期号: 9, 页码: 928-934
作者:  
李连祯;  周倩;  尹娜;  涂晨;  骆永明
  |  收藏  |  浏览/下载:142/0  |  提交时间:2020/06/17
微塑料  生菜  聚苯乙烯微球  吸收  积累  健康风险  microplastics  lettuce  polystyrene microbeads  uptake  accumulation  human health risk  Microplastic (MP, 100 nm-5 mm) may present an attributable risk to ecosystem and human health, and its pollution has become a global environmental concern. Despite a wealth of information on the accumulation of MPs in aquatic species, there is no information on the uptake and accumulation of MPs by higher plants. Terrestrial edible plants are directly exposed to MPs when agricultural soil was applied with organic manure, sewage sludge as fertilizer or plastic mulching. In this paper, the uptake of two sizes of polystyrene (PS) microbeads (0.2 and 1.0 mum) and then their distribution and migration in an edible plant lettuce were firstly investigated based on laboratory experiments. We used fluorescent markers to track PS microbeads in plant tissues and found fluorescence to be a sensitive and reliable detection method. Sections from untreated control lettuce showed no autofluorescence. When roots were treated with fluorescently labeled PS microbeads, the microbeads could be identified by its fluorescence. Our main study investigated the uptake of 0.2 mum beads, as few luminescence signals were observed in lettuce roots for 1.0 mum beads in our experiment. We observed that 0.2 mum fluorescent microbeads were extracellularly trapped in the root cap mucilage (which is a highly hydrated polysaccharide) and a dark green tip (which was typical of lettuce roots exposed to label PS beads) was usually visible to the naked eye. Confocal images revealed that the PS luminescence signals were mainly located in the vascular system and on the cell walls of the cortex tissue of the roots, indicated that the beads passed through the intercellular space via the apoplastic transport system. Once inside the central cylinder, the 0.2 mum PS beads were transferred from the roots to the stems and leaves via the vascular system following the transpiration stream. We also observed that the PS beads adhered to one another and self-assembled systematically into grape-like and (chain) string-like clusters in the intercellular space of the root and stem vascular tissue of lettuce plant. In contrast to the root and stem, PS beads were dispersed in the leaf tissue. Here, for the first time we provide evidence of the adherence, uptake, accumulation, and translocation of submicrometer MPs within an edible plant. Our findings highlight the previously underappreciated human exposure pathway to MPs through the consumption of contaminated crops and emphasize the need for new management strategies to control the release of MPs waste products into the terrestrial environment. Ultimately, the potential impacts of low range sized MPs on food safety of crop plants and human health need to be urgently considered.  
A novel track initiation method for track splitting and merging 会议论文  OAI收割
OCEANS 2016 - Shanghai, Shanghai, China, April 10-13, 2016
作者:  
Li DD(李冬冬);  Zhang Y(张瑶);  Lin Y(林扬);  Liu J(刘健)
收藏  |  浏览/下载:28/0  |  提交时间:2016/08/10
Study on time registration method for photoelectric theodolite data fusion (EI CONFERENCE) 会议论文  OAI收割
10th World Congress on Intelligent Control and Automation, WCICA 2012, July 6, 2012 - July 8, 2012, Beijing, China
Yang H.-T.; Gao H.-B.
收藏  |  浏览/下载:18/0  |  提交时间:2013/03/25
A novel miniature absolute metal rotary encoder based on Single-track Periodic Gray Code (EI CONFERENCE) 会议论文  OAI收割
2012 2nd International Conference on Instrumentation and Measurement, Computer, Communication and Control, IMCCC 2012, December 8, 2012 - December 10, 2012, Harbin, Heilongjiang, China
作者:  
Sun Y.;  Yang S.-W.;  Sun Y.;  Wan Q.-H.
收藏  |  浏览/下载:27/0  |  提交时间:2013/03/25
In order to improve the resolution and enhance the impact resistance and vibration resistance of encoders  a novel absolute metal rotary encoder based on Single-track Periodic Gray Code is presented. The configuration and working principle of the encoder is introduced  and then the metal code disc which can realize full scale absolute encoding on one single track and its corresponding metal slit disc are proposed. Finally  the data acquisition and processing system based on FPGA of encoder is presented. The resolution of the encoder can reach 5.27through electronic subdivision and calibration between the precision code and the coarse code with its volume only 4840mm. The encoder has some advantages such as small volume  low cost  high resolution and strong impact resistance. 2012 IEEE.  
A vertex tracking technique based on airborne opticalequipment (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Electronics and Optoelectronics, ICEOE 2011, July 29, 2011 - July 31, 2011, Dalian, China
Li Q.
收藏  |  浏览/下载:13/0  |  提交时间:2013/03/25
The new approach for infrared target tracking based on the particle filter algorithm (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
作者:  
Sun H.;  Han H.-X.;  Sun H.
收藏  |  浏览/下载:56/0  |  提交时间:2013/03/25
Target tracking on the complex background in the infrared image sequence is hot research field. It provides the important basis in some fields such as video monitoring  precision  and video compression human-computer interaction. As a typical algorithms in the target tracking framework based on filtering and data connection  the particle filter with non-parameter estimation characteristic have ability to deal with nonlinear and non-Gaussian problems so it were widely used. There are various forms of density in the particle filter algorithm to make it valid when target occlusion occurred or recover tracking back from failure in track procedure  but in order to capture the change of the state space  it need a certain amount of particles to ensure samples is enough  and this number will increase in accompany with dimension and increase exponentially  this led to the increased amount of calculation is presented. In this paper particle filter algorithm and the Mean shift will be combined. Aiming at deficiencies of the classic mean shift Tracking algorithm easily trapped into local minima and Unable to get global optimal under the complex background. From these two perspectives that "adaptive multiple information fusion" and "with particle filter framework combining"  we expand the classic Mean Shift tracking framework.Based on the previous perspective  we proposed an improved Mean Shift infrared target tracking algorithm based on multiple information fusion. In the analysis of the infrared characteristics of target basis  Algorithm firstly extracted target gray and edge character and Proposed to guide the above two characteristics by the moving of the target information thus we can get new sports guide grayscale characteristics and motion guide border feature. Then proposes a new adaptive fusion mechanism  used these two new information adaptive to integrate into the Mean Shift tracking framework. Finally we designed a kind of automatic target model updating strategy to further improve tracking performance. Experimental results show that this algorithm can compensate shortcoming of the particle filter has too much computation  and can effectively overcome the fault that mean shift is easy to fall into local extreme value instead of global maximum value.Last because of the gray and fusion target motion information  this approach also inhibit interference from the background  ultimately improve the stability and the real-time of the target track. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).  
The ship-borne infrared searching and tracking system based on the inertial platform (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
作者:  
Li Y.;  Zhang H.;  Zhang H.;  Li Y.;  Li Y.
收藏  |  浏览/下载:35/0  |  提交时间:2013/03/25
As a result of the radar system got interferenced or in the state of half silent  it can cause the guided precision drop badly In the modern electronic warfare  therefore it can lead to the equipment depended on electronic guidance cannot strike the incoming goals exactly. It will need to rely on optoelectronic devices to make up for its shortcomings  but when interference is in the process of radar leading  especially the electro-optical equipment is influenced by the roll  pitch and yaw rotation  it can affect the target appear outside of the field of optoelectronic devices for a long time  so the infrared optoelectronic equipment can not exert the superiority  and also it cannot get across weapon-control system "reverse bring" missile against incoming goals. So the conventional ship-borne infrared system unable to track the target of incoming quickly  the ability of optoelectronic rivalry declines heavily.Here we provide a brand new controlling algorithm for the semi-automatic searching and infrared tracking based on inertial navigation platform. Now it is applying well in our XX infrared optoelectronic searching and tracking system. The algorithm is mainly divided into two steps: The artificial mode turns into auto-searching when the deviation of guide exceeds the current scene under the course of leading for radar.When the threshold value of the image picked-up is satisfied by the contrast of the target in the searching scene  the speed computed by using the CA model Least Square Method feeds back to the speed loop. And then combine the infrared information to accomplish the closed-loop control of the infrared optoelectronic system tracking. The algorithm is verified via experiment. Target capturing distance is 22.3 kilometers on the great lead deviation by using the algorithm. But without using the algorithm the capturing distance declines 12 kilometers. The algorithm advances the ability of infrared optoelectronic rivalry and declines the target capturing time by using semi-automatic searching and reliable capturing-tracking  when the lead deviation of the radar is great. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).  
The research and implementation of the method of the Photoelectric theodolite simulation (EI CONFERENCE) 会议论文  OAI收割
2010 3rd International Conference on Advanced Computer Theory and Engineering, ICACTE 2010, August 20, 2010 - August 22, 2010, Chengdu, China
作者:  
Li Y.;  Lu M.;  Li Y.;  Li Y.;  Li Y.
收藏  |  浏览/下载:16/0  |  提交时间:2013/03/25
Study particle filter tracking and detection algorithms based on DSP signal processors (EI CONFERENCE) 会议论文  OAI收割
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
Dong Y.; Chuan W.
收藏  |  浏览/下载:19/0  |  提交时间:2013/03/25
In Video tracking  detection and tracking usually need two algorithms. The process is complex and need much time which detection and tracking are. In this paper a hybrid valued sequential state vector is formulated. The state vector is characterized by information of target appearance flag and of location. Particle filter-based method implements detection and tracking at one time. In order to reduce process time and think of pixel position in tracking field  feature histogram of luminance is as observe vector and used posterior estimate. In this paper  the luminance component is derived and target is recognized and tracked through image processor based on DSP in order to implementing real-time. The experimental results confirm that method can detect and track the object in real-time successfully when the number of particles is 160. The method is robust for rolling  scale and partial occlusion. 2010 IEEE.