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Efficient generation of targeted point mutations in the Brassica oleracea var.botrytis genome via a modified CRISPR/Cas9 system 被引量:5
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作者 Guixiang Wang Mei Zong +7 位作者 Di Liu Yage Wu Shouwei Tian Shuo Han Ning Guo Mengmeng Duan Liming Miao Fan Liu 《Horticultural Plant Journal》 SCIE CAS CSCD 2022年第4期527-530,共4页
In this study,we used the modified CRISPR/Cas9 system to produce targeted point mutations in cauliflower.Acetolactate synthase(ALS)and Centromere-specific histone H3 variant(CENH3)genes were selected as the base-editi... In this study,we used the modified CRISPR/Cas9 system to produce targeted point mutations in cauliflower.Acetolactate synthase(ALS)and Centromere-specific histone H3 variant(CENH3)genes were selected as the base-editing targets and hypocotyls of cauliflower were used as explants.For ALS gene,a C-to-T conversion in the Pro182 codon(CCT)can alter the encoded amino acid,likely resulting in herbicide resistance,and a C-to-T mutation in the Leu133 codon(CTT)in the CENH3 gene may produce a haploid inducer.Results indicated that the transformation efficiency was 1.8%–4.5%and the mutation efficiencies for the ALS and CENH3 genes were approximately 22%and 87%,respectively.The ALS mutant cauliflower showed strong herbicide resistance,with possible immediate implications for broadleaf weed control in cauliflower fields. 展开更多
关键词 CAULIFLOWER targeted point mutations Base-editing CRISPR/Cas9 ALS CENH3
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A Moving IR Point Target Detection Algorithm Based on Reverse Phase Feature of Neighborhood in Difference Between Neighbor Frame Images 被引量:3
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作者 朱风云 秦世引 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2006年第3期225-232,共8页
An algorithm for detecting moving IR point target in complex background is proposed, which is based on the Reverse Phase Feature of Neighborhood (RPFN) of target in difference between neighbor frame images that two ... An algorithm for detecting moving IR point target in complex background is proposed, which is based on the Reverse Phase Feature of Neighborhood (RPFN) of target in difference between neighbor frame images that two positions of the target in the difference image are near and the gray values of them are close to in absolute value but with inverse sign. Firstly, pairs of points with RPFN are detected in the difference image between neighbor frame images, with which a virtual vector graph is made, and then the moving point target can be detected by the vectors' sequence cumulated in vector graphs. In addition, a theorem for the convergence of detection of target contrail by this algorithm is given and proved so as to afford a solid guarantee for practical applications of the algorithm proposed in this paper. Finally, some simulation results with 1000 frames from 10 typical images in complex background show that moving point targets with SNR not lower than 1.5 can be detected effectively. 展开更多
关键词 pattern recognition target detection point target difference image RPFN
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The combined FSS-SPRT method for detection and tracking of low SNR point targets
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作者 张海英 张田文 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第2期174-179,共6页
For the detection and tracking of dim point targets with SNR 〈 2 dB, the combined SPRT and FSS method is given to accomplish detection in whicb likelihood testing are carried out twice to prune constantly. Firstly, t... For the detection and tracking of dim point targets with SNR 〈 2 dB, the combined SPRT and FSS method is given to accomplish detection in whicb likelihood testing are carried out twice to prune constantly. Firstly, the SPRT is developed aiming at the heuristic segments formed by correlation analysis. In order to avoid missing detection the threshold is chosen much lower. Secondly, by adding samples and choosing the one most similar to the heuristic segment to make state estimation FSS is implemented. This time we choose a higher threshold. Moreover in preprocessing the compound kernel estimation is designed to depress varying background clutter. Multiple experimental sequences validate that the method is more suitable for the dim targets detection and tracking compared with the scheme choosing the higher intensity pixel in tracking. It not only has perfect detection performance but also can greatly enhance tracking performance. 展开更多
关键词 kernel estimation SPRT point target heuristic segment directional correlation filters
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A High Speed Detection Scheme for Point Targets in a Multitarget Environment
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作者 Song Liuping and Sun ZhongkangDept. of Electronic Eng., National Univ. of Defense Technology, Changsha 410073, China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1991年第2期109-123,共15页
The purpose of this paper is to develop a high speed detection scheme for moving and / or stationary point targets in a multitarget environment as registered in an IR image sequence. An iterative approximate 3-D line ... The purpose of this paper is to develop a high speed detection scheme for moving and / or stationary point targets in a multitarget environment as registered in an IR image sequence. An iterative approximate 3-D line searching algorithm based upon the geometric representation of lines (for non-maneuvering targets in space) in a 3-D space is derived. The convergency of the algorithm is proved. An analysis is performed of the theoretical detection performance of the algorithm. The statistical experiment results show high effectiveness and computational efficiency of the algorithm in the case of low SNR. The idea may be employed to satisfy the real-time processing requirement of an IR system. 展开更多
关键词 Point target Three-dimensional space(3-D space) Iterative algorithm Objective function Convergency.
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Weapon effectiveness and the shapes of damage functions 被引量:5
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作者 Sei-Hoon Moon 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第2期617-632,共16页
This paper provides a review of methods of assessing a fragmentation weapon’s effectiveness against a point target or an area target with keeping the focus on the necessity of using the Carleton damage function with ... This paper provides a review of methods of assessing a fragmentation weapon’s effectiveness against a point target or an area target with keeping the focus on the necessity of using the Carleton damage function with the correct shape factor.First,cookie-cutter damage functions are redefined to preserve the shape factor of and to have the same lethal area as the corresponding Carleton damage function.Then,closed-form solutions of the effectiveness methods are obtained by using those cookie-cutter damage functions and the Carleton damage function.Finally,the closed-form solutions are applied to calculate the probability of damaging a point target and the expected fractional damage to an area target for several attack scenarios by using cookie-cutter damage functions and the Carleton damage functions with different shape factors.The comparison of the calculation results shows that using cookie-cutter damage functions or the Carleton damage function with a wrong shape factor results in quite significant differences from using the original Carleton damage function with a correct shape factor when weapon’s delivery error deviations are less than or comparable to the lengths of the lethal area and the aim point is far from a target.The effectiveness methods improved in this paper will be useful for mission planning utilizing the precision-guided munitions in circumstances where the collateral damage should be reduced. 展开更多
关键词 Weapon effectiveness Point target Area target Cookie-cutter damage function Carleton damage function
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