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Review on the Technological Development and Application of UAV Systems

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Chinese Journal of Electronics 2020年第2期29卷 199-207页

作者： FAN Bangkui li yun ZHANG Ruiyu FU Qiqi Chinese Academy of Engineering

Unmanned aerial vehicles(UAVs) are products of deep integration of aviation technology and Information technology(IT). The core factor of why the UAV industry can become a relatively independent industry and experience rapid development is the full penetration of IT into the aviation industry. Under the networked environment, UAVs are now becoming datadriven mobile agents. With the development of information technology, information transmission networking, operation space digitizing, and flight platform intelligentizing will become the main trends of technological development of UAV systems. The application of UAV systems is not merely a paradigm in transportation, but will more importantly produce "UAV+" novel production modes,service formats, and combat modes associated with *** emerging trends will have profound impacts on future economic and social development as well as the building of armed forces.

关键词： Unmanned aerial vehicle(UAV) Information technology(IT) Information network Data driven Mobile agent

社区工作者自我效能感、感知社会支持与获得感关系探究——以广西社区工作者为例

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青海民族大学学报(社会科学版) 2025年第1期51卷 137-145页

作者：朱丽王写兰李晓昀华东政法大学上海201620 广西民族大学广西南宁530006

加强社区工作者队伍建设,事关保障人民安居乐业,事关维护社会安定有序,事关巩固党的长期执政根基;关注社区工作者的获得感,可以使其以更加积极的状态服务社区建设,提高社区治理水平。本文基于自我决定理论和“工作要求—资源模型”,以... 详细信息

加强社区工作者队伍建设,事关保障人民安居乐业,事关维护社会安定有序,事关巩固党的长期执政根基;关注社区工作者的获得感,可以使其以更加积极的状态服务社区建设,提高社区治理水平。本文基于自我决定理论和“工作要求—资源模型”,以广西社区工作者为研究对象,基于收集到的3527份有效样本数据,检验社区工作者自我效能感对社区工作者获得感的直接效应,以及感知社会支持在内部自我效能感与获得感之间的调节作用。研究主要发现:社区工作者外部自我效能感和内部自我效能感,均对社区工作者获得感具有正向影响;社区工作者感知到的社会支持程度越高,内部自我效能感对获得感的增进作用越强。论文聚焦自我效能感、感知社会支持与社区工作者获得感的关系,对积极构建更具包容性的社区环境,激发社区工作者想干事、能干事、干成事的信心和决心,引导社区工作者在为民服务的治理实践中增进职业获得感等方面具有实践启示。

关键词：社区工作者获得感自我效能感感知社会支持

Cytogenetics and germplasm enrichment in Brassica allopolyploids in China

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Journal of Integrative Agriculture 2017年第12期16卷 2698-2708页

作者： li Zai-yun WANG You-ping National Key Laboratory of Crop Genetic Improvement College of Plant Science and TechnologyHuazhong Agricultural University College of Bioscience and Biotechnology Yangzhou University Key Laboratory of Agrobiology of Jiangsu Jiangsu Academy of Agricultural Sciences

This paper reviews research advances in cytogenetics and germplasm innovation in Brassica allopolyploids, particularly oilseed rape（Brassica napus）, in China. Three naturally evolved Brassica allotetraploid species are cytologically stable but tend to preferentially lose several chromosomes from one subgenome when induced by alien chromosome elimination. A-subgenome is extracted from B. napus, and the ancestral Brassica rapa was restituted after the total loss of C-subgenome chromosomes. Genome-wide genetic and epigenetic alterations were observed in both natural and synthetic Brassica allotetraploids. B. napus was subjected to extensive interspecific hybridization with landraces of B. rapa and Brassica juncea, which exhibit abundant phenotype variations, to widen the genetic diversity in breeding and select numerous elite germplasm resources and cultivars; these cultivars include the representative Zhongyou 821, which also parented numerous other varieties. Novel B. napus genotypes were obtained using Brassica trigenomic hybrids and allohexaploids（2 n=54, AABBCC） by combining subgenomes from extant allotetraploids and diploids as bridge. Alien additions, substitutions, and translocations of the B. napus genome were developed by intergeneric/intertribal sexual and somatic hybridizations with several crucifers. Furthermore, mitochondrial DNA recombination promoted the production of novel cytoplasmic male sterile lines.

关键词： Brassica napus germplasm Brassica rapa Brassicajuncea cytogenetics

Phenotypic Plasticity of life History Characteristics: Quantitative Analysis of Delayed Reproduction of Green Foxtail (Setaria viridis) in the Songnen Plain of China

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Journal of Integrative Plant Biology 2008年第6期50卷 641-647页

作者： Hai-Yan li yun-Fei Yang Institute of Grassland Science Northeast Normal University Key Laboratory of Vegetation Ecology Ministry of Education Changchun 130024 China

Green foxtail （Setaria viridis L.） is a common weed species in temperate regions. Research on the effect of delayed reproduction on the phenotypic plasticity and regularity of the vegetative and reproductive growth is of vital significance for understanding population regulation and control of the weed in the growing season. Green foxtail seeds were sown every 10 days from 25 June to 24 August of 2004. The growth and production metrics were measured via harvesting tufts and statistical analysis was carried out. The results showed that the reproductive tillers, seed number, seed biomass and one thousand-seed weight of plants at the first sowing （25 June） approximately increased 28.8, 7 827.0, 1 104,0 and 12.3 times compared with that at the last sowing （24 August）, respectively. Total tillers, reproductive tillers and height increased linearly as the reproductive period delayed, however, biomass increased exponentially. Quadratic equations best explained the relationships between the delayed reproductive period and seed number, inflorescence length, one thousand-seed weight, seed biomass. Based on the quantity and quality of seed production, weeding young seedlings emerging before July can be the most effective weed-control strategy in the Songnen Plain.

关键词： delayed reproduction life history phenotypic plasticity quantitative characteristics Setaria viridis weed control

Immersed Hypersurfaces in the Unit Sphere S^(m+1) with Constant Blaschke Eigenvalues

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Acta Mathematica Sinica,English Series 2007年第3期23卷 533-548页

作者： Xing Xiao li Feng yun ZHANG Department of Mathematics He'nan Normal University Xinxiang 453007 He'nan P. R. China

For an immersed submanifold x ： M^m→ Sn in the unit sphere S^n without umbilics, an eigenvalue of the Blaschke tensor of x is called a Blaschke eigenvalue of x. It is interesting to determine all hypersurfaces in Sn with constant Blaschke eigenvalues. In this paper, we are able to classify all immersed hypersurfaces in S^m＋1 with vanishing MSbius form and constant Blaschke eigenvalues, in case （1） x has exact two distinct Blaschke eigenvalues, or （2） m = 3. With these classifications, some interesting examples are also presented.

关键词： Moebius form Blaschke eigenvalues Blaschke tensor MSbius metric MSbius second fundamental form

The classification of bi-quintic parametric polynomial minimal surfaces

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Applied Mathematics(A Journal of Chinese Universities) 2017年第1期32卷 14-26页

作者： li Cai-yun ZHU Chun-gang School of Mathematics and Physics Science Dalian University of Technology Panjin 124221 China School of Mathematical Sciences Dalian University of Technology Dalian 116024 China

Parametric polynomial surface is a fundamental element in CAD systems. Since the most of the classic minimal surfaces are represented by non-parametric polynomial, it is interesting to study the minimal surfaces represented in parametric polynomial form. Recently,Ganchev presented the canonical principal parameters for minimal surfaces. The normal curvature of a minimal surface expressed in these parameters determines completely the surface up to a position in the space. Based on this result, in this paper, we study the bi-quintic isothermal minimal surfaces. According to the condition that any minimal isothermal surface is harmonic,we can acquire the relationship of some control points must satisfy. Follow up, we obtain two holomorphic functions f（z） and g（z） which give the Weierstrass representation of the minimal surface. Under the constrains that the minimal surface is bi-quintic, f（z） and g（z） can be divided into two cases. One case is that f（z） is a constant and g（z） is a quadratic polynomial, and another case is that the degree of f（z） and g（z） are 2 and 1 respectively. For these two cases,we transfer the isothermal parameter to canonical principal parameter, and then compute their normal curvatures and analyze the properties of the corresponding minimal surfaces. Moreover,we study some geometric properties of the bi-quintic harmonic surfaces based on the B′ezier representation. Finally, some numerical examples are demonstrated to verify our results.

关键词： polynomial parametric curvature canonical compute quadratic satisfy isothermal acquire verify

Statistical Modeling of CMIP5 Projected Changes in Extreme Wet Spells over China in the Late 21st Century

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Journal of Meteorological Research 2017年第4期31卷 678-693页

作者： lianhua ZHU yun li Zhihong JIANG Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science &Technology Nanjing 210044 China School of Mathematics and Statistics Nanjing University of Information Science & Technology Nanjing 210044 China Business Intelligence & Data Analytics Western Power WA 6000 Australia

The observed intensity, frequency, and duration（IFD） of summer wet spells, defined here as extreme events with one or more consecutive days in which daily precipitation exceeds a given threshold（the 95th percentile）, and their future changes in RCP4.5 and RCP8.5 in the late 21st century over China, are investigated by using the wet spell model（WSM） and by extending the point process approach to extreme value analysis. Wet spell intensity is modeled by a conditional generalized Pareto distribution, frequency by a Poisson distribution, and duration by a geometric distribution, respectively. The WSM is able to realistically model summer extreme rainfall spells during 1961–2005, as verified with observations at 553 stations throughout China. To minimize the impact of systematic biases over China in the global climate models（GCMs） of the Coupled Model Intercomparison Project Phase 5（CMIP5）, five best GCMs are selected based on their performance to reproduce observed wet spell IFD and average precipitation during the historical period. Furthermore, a quantile–quantile scaling correction procedure is proposed and applied to produce ensemble projections of wet spell IFD and corresponding probability distributions. The results show that in the late 21st century, most of China will experience more extreme rainfall and less low-intensity rainfall. The intensity and frequency of wet spells are projected to increase considerably, while the duration of wet spells will increase but to a much less extent. The IFD changes in RCP8.5 are in general much larger than those in RCP4.5.

关键词： wet spell model extreme value theory bias correction Coupled Model Intercomparison Project Phase 5

On the Blaschke Isoparametric Hypersurfaces in the Unit Sphere

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Acta Mathematica Sinica,English Series 2009年第4期25卷 657-678页

作者： Xing Xiao li Feng yun ZHANG Department of Mathematics. He'nan Normal University Xinxiang 453007 P. R. China

Given an immersed submanifold x ： M^M → S^n in the unit sphere S^n without umbilics, a Blaschke eigenvalue of x is by definition an eigenvalue of the Blaschke tensor of x. x is called Blaschke isoparametric if its Mobius form vanishes identically and all of its Blaschke eigenvalues are constant. Then the classification of Blaschke isoparametric hypersurfaces is natural and interesting in the MSbius geometry of submanifolds. When n = 4, the corresponding classification theorem was given by the authors. In this paper, we are able to complete the corresponding classification for n = 5. In particular, we shall prove that all the Blaschke isoparametric hypersurfaces in S^5 with more than two distinct Blaschke eigenvalues are necessarily Mobius isoparametric.

关键词： Mobius form Blaschke eigenvalues Blaschke tensor Mobius metric Mobius second fundamental form

Correspondence between quantum-optical transform and classical-optical transform explored by developing Dirac＇s symbolic method

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Frontiers of physics 2012年第3期7卷 261-310页

作者： Hong-yi Fan li-yun Hu Department of Physics Shanghai Jiao Tong UniversityShanghai 200030China College of Physics&Communication Electronics Jiangxi Normal UniversityNanchang 330022China Department of Material Science and Engineering University of Science and Technology of China Hefei 230026 China

By virtue of the new technique of performing integration over Dirac＇s ket-bra operators, we ex- plore quantum optical version of classical optical transformations such as optical Fresnel transform, Hankel transform, fractional Fourier transform, Wigner transform, wavelet transform and Fresnel- Hadmard combinatorial transform etc. In this way one may gain benefit for developing classical optics theory from the research in quantum optics, or vice-versa. We cannot only find some new quantum mechanical unitary operators which correspond to the known optical transformations, de- riving a new theorem for calculating quantum tomogram of density operators, but also can reveal some new classical optical transformations. For examples, we find the generalized Fresnel opera- tor （GFO） to correspond to the generalized Fresnel transform （GFT） in classical optics. We derive GFO＇s normal product form and its canonical coherent state representation and find that GFO is the loyal representation of symplectic group multiplication rule. We show that GFT is just the transformation matrix element of GFO in the coordinate representation such that two successive GFTs is still a GFT. The ABCD rule of the Gaussian beam propagation is directly demonstrated in the context of quantum optics. Especially, the introduction of quantum mechanical entangled state representations opens up a new area in finding new classical optical transformations. The complex wavelet transform and the condition of mother wavelet are studied in the context of quantum op- tics too. Throughout our discussions, the coherent state, the entangled state representation of the two-mode squeezing operators and the technique of integration within an ordered product （IWOP） of operators are fully used. All these have confirmed Dirac＇s assertion：＂...for a quantum dynamic system that has a classical analogue, unitary transformation in the quantum theory is the analogue of contact transformation in the classical theory＂.

关键词： Dirac's symbolic method IWOP technique entangled state of continuum variables entangled Fresnel transform Collins formula Generalized Fresnel operator complex wavelet trans-form complex Wigner transform complex fractional Fourier transform symplectic wavelet trans-form entangled symplectic wavelet transform Symplectic-dilation mixed wavelet transform frac-tional Radon transform new eigenmodes of fractional Fourier transform