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Almost Fixed Points and Fixed Points of Upper [Lower] Semicontinuous Multimap on Locally G-convex Spaces 被引量:3
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作者 朴勇杰 《Northeastern Mathematical Journal》 CSCD 2005年第4期391-396,共6页
In this paper, we use the well known KKM type theorem for generalized convex spaces due to Park (Elements of the KKM theory for generalized convex spaces, Korean J. Comp. Appl. Math., 7(2000), 1-28) to obtain an a... In this paper, we use the well known KKM type theorem for generalized convex spaces due to Park (Elements of the KKM theory for generalized convex spaces, Korean J. Comp. Appl. Math., 7(2000), 1-28) to obtain an almost fixed point theorem for upper [resp., lower] semicontinuous multimaps in locally G-convex spaces, and then give a fixed point theorem for upper semicontinuous multimap with closed Γ-convex values. 展开更多
关键词 G-convex space upper [lower] semicontinuous locally G-convex space ahnost fixed point property ahnost Γ-convex
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THE PRECISE NORM OF A CLASS OF FORELLI-RUDIN TYPE OPERATORS ON THE SIEGEL UPPER HALF SPACE
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作者 Lifang ZHOU Yun FAN Jin LU 《Acta Mathematica Scientia》 SCIE CSCD 2021年第5期1537-1546,共10页
The precise L^(p) norm of a class of Forelli-Rudin type operators on the Siegel upper half space is given in this paper.The main result not only implies the upper L^(p) norm estimate of the Bergman projection,but also... The precise L^(p) norm of a class of Forelli-Rudin type operators on the Siegel upper half space is given in this paper.The main result not only implies the upper L^(p) norm estimate of the Bergman projection,but also implies the precise L^(p) norm of the Berezin transform. 展开更多
关键词 precise L^(p)norm Forelli-Rudin type operators Siegel upper half space Bergman projection Berezin transform
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Some Results of Upper and Lower <i>M</i>-Asymmetric Irresolute Multifunctions in Bitopological Spaces 被引量:1
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作者 Levy K. Matindih Edwin Moyo +1 位作者 Davy K. Manyika Timothy Sinyangwe 《Advances in Pure Mathematics》 2021年第6期611-627,共17页
In this paper, we aim to introduce and study some basic properties of upper and lower M-asymmetric irresolute multifunctions defined between asymmetric sets in the realm of bitopological spaces with certain minimal st... In this paper, we aim to introduce and study some basic properties of upper and lower M-asymmetric irresolute multifunctions defined between asymmetric sets in the realm of bitopological spaces with certain minimal structures as a generalization of irresolute functions deal to Crossley and Hildebrand <a href="#ref1">[1] and upper and lower irresolute Multifunctions deal to Popa <a href="#ref2">[2]. 展开更多
关键词 TiTj-Semiopen Sets M-space M-Asymmetric Semiopen and Semiclosed Sets upper (Lower) Irresolute Multifunctions and upper (Lower) M-Asymmetric Irresolute Multifunctions
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Progress in polar upper atmospheric physics research in China 被引量:4
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作者 LIU Ruiyuan YANG Huigen 《Advances in Polar Science》 2012年第2期55-71,共17页
The Chinese Antarctic Great Wall, Zhongshan, Kunlun and Arctic Yellow River stations have unique geographical locations, well suited to carry out polar upper atmospheric observations. This paper reviews the tremendous... The Chinese Antarctic Great Wall, Zhongshan, Kunlun and Arctic Yellow River stations have unique geographical locations, well suited to carry out polar upper atmospheric observations. This paper reviews the tremendous history of nearly 30 years of Chinese polar expeditions and major progress in polar upper atmospheric physics research. This includes the polar upper atmospheric physics conjugate observation system at Zhongshan Station in the Antarctic and Yellow River Station in the Arctic, and original research achievements in polar ionospheric fields, aurora and particle precipitation, the polar current system, polar plasma convection, geomagnetic pulsations and space plasma waves, inter-hemispheric comparisons of the space environment, space weather in polar regions, power spectrum of the incoherent scatter radar, ionospheric heating experiments and polar meso- spheric summer echoes, polar ionosphere-magnetosphere numerical simulation and others. Finally, prospects for Chinese polar upper atmospheric physics research are outlined. 展开更多
关键词 upper atmospheric physics space physics geospace polar region IONOSPHERE AURORA
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The rough representation and measurement of quotient structure in algebraic quotient space model 被引量:5
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作者 陈林书 Wang Jiayang 《High Technology Letters》 EI CAS 2017年第3期293-297,共5页
Granular computing is a very hot research field in recent years. In our previous work an algebraic quotient space model was proposed,where the quotient structure could not be deduced if the granulation was based on an... Granular computing is a very hot research field in recent years. In our previous work an algebraic quotient space model was proposed,where the quotient structure could not be deduced if the granulation was based on an equivalence relation. In this paper,definitions were given and formulas of the lower quotient congruence and upper quotient congruence were calculated to roughly represent the quotient structure. Then the accuracy and roughness were defined to measure the quotient structure in quantification. Finally,a numerical example was given to demonstrate that the rough representation and measuring methods are efficient and applicable. The work has greatly enriched the algebraic quotient space model and granular computing theory. 展开更多
关键词 granular computing algebraic quotient space model quotient structure upper(lower) congruence relation
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Some Estimates for Commutators of Fractional Integrals Associated to Operators with Gaussian Kernel Bounds on Weighted Morrey Spaces 被引量:3
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作者 Hua Wang 《Analysis in Theory and Applications》 2013年第1期72-85,共14页
Let L be the infinitesimal generator of an analytic semigroup on L^2 (R^n) with Gaussian kernel bound, and let L^-α/2 be the fractional integrals of L for 0 〈 α 〈 n. In this paper, we will obtain some boundedn... Let L be the infinitesimal generator of an analytic semigroup on L^2 (R^n) with Gaussian kernel bound, and let L^-α/2 be the fractional integrals of L for 0 〈 α 〈 n. In this paper, we will obtain some boundedness properties of commutators [b, L^-α/2] on weighted Morrey spaces L^p,k(w) when the symbol b belongs to BMO(Rn) or the homogeneous Lipschitz space. 展开更多
关键词 Gaussian upper bound fractional integral weighted Morrey space commutator.
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Maps to Ordered Topological Vector Spaces and Stratifiable Spaces
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作者 Erguang YANG Yun XU 《Journal of Mathematical Research with Applications》 CSCD 2018年第1期77-84,共8页
In the paper [Monotone countable paracompactness and maps to ordered topological vector spaces, Top. Appl., 2014, 169(3): 51–70], Yamazaki initiated the study on maps with values into ordered topological vector sp... In the paper [Monotone countable paracompactness and maps to ordered topological vector spaces, Top. Appl., 2014, 169(3): 51–70], Yamazaki initiated the study on maps with values into ordered topological vector spaces. Characterizations of monotonically countably paracompact spaces and some other spaces in terms of maps to ordered topological vector spaces were obtained. In this paper, following Yamazaki's method, we present some characterizations of stratifiable spaces and k-semi-stratifiable spaces in terms of maps with values into ordered topological vector spaces. 展开更多
关键词 stratifiable spaces k-semi-stratifiable spaces maps to ordered topological vector spaces lower(upper semi-continuity
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Rough Sets in Approximate Solution Space
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作者 Hui Sun Wei Tian Qing Liu 《南昌工程学院学报》 CAS 2006年第2期70-73,共4页
As a new mathematical theory, Rough sets have been applied to processing imprecise, uncertain and incomplete data. It has been fruitful in finite and non-empty set. Rough sets, however, are only served as the theoreti... As a new mathematical theory, Rough sets have been applied to processing imprecise, uncertain and incomplete data. It has been fruitful in finite and non-empty set. Rough sets, however, are only served as the theoretic tool to discretize the real function. As far as the real function research is concerned, the research to define rough sets in the real function is infrequent. In this paper, we exploit a new method to extend the rough set in normed linear space, in which we establish a rough set,put forward an upper and lower approximation definition, and make a preliminary research on the property of the rough set.A new tool is provided to study the approximation solutions of differential equation and functional variation in normed linear space. This research is significant in that it extends the application of rough sets to a new field. 展开更多
关键词 rough sets approximate solution space upper and lower approximation
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MONOTONICITY IN ORLICZ-LORENTZ SEQUENCE SPACES EQUIPPED WITH THE ORLICZ NORM 被引量:1
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作者 巩万中 张道祥 《Acta Mathematica Scientia》 SCIE CSCD 2016年第6期1577-1589,共13页
In Orlicz-Lorentz sequence space Aψ,w with the Orlicz norm, uniform monotonic- ity, points of upper local uniform monotonicity and lower local uniform monotonicity are characterized. Moreover, the monotonicity coeffi... In Orlicz-Lorentz sequence space Aψ,w with the Orlicz norm, uniform monotonic- ity, points of upper local uniform monotonicity and lower local uniform monotonicity are characterized. Moreover, the monotonicity coefficient in Aψ,w are discussed. 展开更多
关键词 Orlicz-Lorentz sequence space Orlicz norm point of upper (lower) local uni-form monotonicity uniform monotonicity monotone coefficient
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On <i>M</i>-Asymmetric Semi-Open Sets and Semicontinuous Multifunctions in Bitopological Spaces 被引量:2
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作者 Levy K. Matindih Edwin Moyo 《Advances in Pure Mathematics》 2021年第4期218-236,共19页
The purpose of this paper is to introduce the notions of m-asymmetric semiopen sets and M-asymmetric semicontinuous multifunctions defined between asymmetric sets satisfying certain minimal conditions in the framework... The purpose of this paper is to introduce the notions of m-asymmetric semiopen sets and M-asymmetric semicontinuous multifunctions defined between asymmetric sets satisfying certain minimal conditions in the framework of bitopological spaces. Some new characterizations of m-asymmetric semiopen sets and M-asymmetric semicontinuous multifunctions will be investigated and several fundamental properties will be obtained. 展开更多
关键词 m-spaces m-Semiasymmetric Open and Closed Sets upper and Lower M-Asymmetric Semicontinuous Multifunction
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Space Complexity of Algorithm for Modular Multiplicative Inverse
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作者 Boris S. Verkhovsky 《International Journal of Communications, Network and System Sciences》 2011年第6期357-363,共7页
In certain computational systems the amount of space required to execute an algorithm is even more restrictive than the corresponding time necessary for solution of a problem. In this paper an algorithm for modular mu... In certain computational systems the amount of space required to execute an algorithm is even more restrictive than the corresponding time necessary for solution of a problem. In this paper an algorithm for modular multiplicative inverse is introduced and its computational space complexity is analyzed. A tight upper bound for bit storage required for execution of the algorithm is provided. It is demonstrated that for range of numbers used in public-key encryption systems, the size of bit storage does not exceed a 2K-bit threshold in the worst-case. This feature of the Enhanced-Euclid algorithm allows designing special-purpose hardware for its implementation as a subroutine in communication-secure wireless devices. 展开更多
关键词 MODULAR MULTIPLICATIVE INVERSE Public-Key Encryption space Complexity Tight upper Bound Extended EUCLID ALGORITHM Prefix Coding Enhanced EUCLID ALGORITHM Custom-Built Circuits
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MONOTONE POINTS IN ORLICZ-BOCHNER SEQUENCE SPACES
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作者 Wanzhong Gong Zhongrui Shi 《Analysis in Theory and Applications》 2012年第4期301-311,共11页
In Orlicz-Bochner sequence spaces endowed with Orlicz norm and Luxemburg norm, points of lower monotonicity, upper monotonicity, lower local uniform monotonicity and upper local uniform monotonicity are characterized.
关键词 Banach lattice Orlicz-Bochner space Luxemburg norm Orlicz norm upper(lower) monotone point upper (lower) locally uniformly monotone point
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Some Characterizations of Upper and Lower M-Asymmetric Preirresolute Multifunctions
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作者 Levy Kahyata Matindih Elijah Bwanga Mpelele +1 位作者 Jimmy Hambulo Davy Kabuswa Manyika 《Advances in Pure Mathematics》 2023年第5期267-283,共17页
In this present paper, we introduce and investigate a new form of mappings namely;upper and lower M-asymmetric preirresolute multifunctions defined between M-structural asymmetric topological spaces. The relationships... In this present paper, we introduce and investigate a new form of mappings namely;upper and lower M-asymmetric preirresolute multifunctions defined between M-structural asymmetric topological spaces. The relationships between the multifunctions in our sense and other types of precountinuous and preirresolute multifunctions defined on both symmetric and asymmetric topological structures are discussed. 展开更多
关键词 Asymmetric-Preopen Sets M-space M-Asymmetric Preopen Sets upper (Lower) Preirresolute Multifunctions upper (lower) M-Asymmetric Preirresolute Multifunctions
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甘南黄河上游植被覆盖度时空变化与地形因子的关系
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作者 张起鹏 路红娥 +1 位作者 赵頔琛 卓玛兰草 《干旱区研究》 北大核心 2025年第3期523-533,共11页
甘南黄河上游植被覆盖度在维持高寒生态系统结构稳定和涵养水源等方面发挥着重要的作用,探究植被覆盖度的时空变化及其与地形因子的关系,揭示其植被的时空分布规律,可以更好地理解高寒植被生态系统的动态和功能,为维护生态平衡及植被恢... 甘南黄河上游植被覆盖度在维持高寒生态系统结构稳定和涵养水源等方面发挥着重要的作用,探究植被覆盖度的时空变化及其与地形因子的关系,揭示其植被的时空分布规律,可以更好地理解高寒植被生态系统的动态和功能,为维护生态平衡及植被恢复提供理论支持。本文基于甘南黄河上游1990—2020年4期Landsat影像及数字高程模型(Digital Elevation Model,DEM)数据,采用像元二分模型、叠加分析、地理探测器等方法,对研究区域的植被覆盖度时空变化及其地形因子的相关性进行研究。结果表明:(1)1990—2020年甘南黄河上游地区的植被覆盖度经历了从退化到恢复,再到显著提升的过程;研究区中高植被覆盖度(0.6~0.8)所占的比例最多,占总面积的77.68%。(2)1990—2020年研究区植被覆盖度呈现出显著的改善趋势,其中,植被覆盖度改善的区域(Slope>0)约占总面积的91.26%,远大于退化区域(Slope<0)的面积。(3)地形因子对植被覆盖度的解释力存在显著差异,海拔是植被覆盖度的主要驱动因子,坡度、坡向和海拔等地形因子交互作用的解释力高于单因子。(4)研究区的植被覆盖度随海拔和坡度的增加都呈先上升后下降的单峰模式;南坡植被覆盖度最高,东北坡相对较低,在时间序列上北到西南方向植被覆盖度面积呈现萎缩状态,而西南、西及西北方向的面积在增大。研究结果可为甘南黄河上游生态保护及高质量发展提供科学支撑。 展开更多
关键词 植被覆盖度 地理探测器 时空变化 地形因子 甘南黄河上游
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非均质软土加筋路基三维稳定性极限上限分析
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作者 李林 孙砖芹 +1 位作者 张浩 朱云波 《哈尔滨工业大学学报》 北大核心 2025年第7期70-80,共11页
非均质软土地区路基的稳定性问题是岩土工程中的关键技术难点,为提升对其三维稳定性问题的评估能力,基于极限上限定理构建了非均质软土加筋路基的三维基底破坏机制,并依据虚功原理建立了相应的能量守恒方程。通过引入遗传算法,开发了一... 非均质软土地区路基的稳定性问题是岩土工程中的关键技术难点,为提升对其三维稳定性问题的评估能力,基于极限上限定理构建了非均质软土加筋路基的三维基底破坏机制,并依据虚功原理建立了相应的能量守恒方程。通过引入遗传算法,开发了一种用于高效求解三维上限解的搜索方法。该三维破坏模式可退化为边坡的三维坡趾破坏形式,并与已有边坡三维上限解进行对比,以验证遗传算法的准确性与计算效率。在此基础上,开展了参数敏感性分析,考察了路基分层特征、非饱和强度特性、抗剪强度非均质性、筋材抗拉强度、铺设层数以及基质吸力等因素对加筋路基三维稳定性的影响。结果表明:在三维基底破坏模式下,非饱和软土地基与路基之间的非均质系数比对稳定性具有提升作用,且该系数比越大,路基越稳定;在筋材抗拉强度不变的条件下,减小筋材间距会削弱基质吸力对稳定性的有利影响;当铺设层数一定时,非均质性越强,筋材增强稳定性的效果越显著。该三维稳定性分析方法可为加筋参数的优化配置和复杂地基条件下的路基设计提供可靠的计算工具和理论依据。 展开更多
关键词 加筋路基 非均质 遗传算法 上限分析 抗拉强度 铺设层数
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Coupled Extremal Quasi-solutions to Nonlinear Impulsive Fredholm Integral Equations in Banach Spaces
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作者 戚仕硕 《Northeastern Mathematical Journal》 CSCD 2000年第3期329-338,共10页
By means of the method of coupled lower and upper quasisolutio ns, the paper applies, instead of establishing the comparison theorem, a new ite rative technique to nonlinear impulsive Fredholm integral equations in ... By means of the method of coupled lower and upper quasisolutio ns, the paper applies, instead of establishing the comparison theorem, a new ite rative technique to nonlinear impulsive Fredholm integral equations in Banach sp aces and proves the existence theorem on their coupled extremal quasisolutions . Finally, an infinite system of nonlinear impulsive integral equations is provi ded to demonstrate the obtained results. 展开更多
关键词 coupled lower and upper quasi-solutions iterative techn ique impulsive Fredholm integral equation Banach space normal cone
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On M-Asymmetric Irresolute Multifunctions in Bitopological Spaces
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作者 Levy K. Matindih Peter J. Banda Danny Mukonda 《Advances in Pure Mathematics》 2022年第8期490-504,共15页
In this paper, our focus is to introduce and investigate a class of mappings called M-asymmetric irresolute multifunctions defined between bitopological structural sets satisfying certain minimal properties. M-asymmet... In this paper, our focus is to introduce and investigate a class of mappings called M-asymmetric irresolute multifunctions defined between bitopological structural sets satisfying certain minimal properties. M-asymmetric irresolute multifunctions are point-to-set mappings defined using M-asymmetric semiopen and semiclosed sets. Some relations between M-asymmetric semicontinuous multifunctions and M-asymmetric irresolute multifunctions are established. This notion of M-asymmetric irresolute multifunctions is analog to that of irresolute multifunctions in the general topological space and, upper and lower M-asymmetric irresolute multifunctions in minimal bitopological spaces, but mathematically behaves differently. 展开更多
关键词 Asymmetric-Semiopen Sets m-space m-Asymmetric Semiopen Sets Irresolute Multifunctions upper (Lower) M-Asymmetric Irresolute Multifunctions M-Asymmetric Irresolute Multifunctions
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上半平面上α-Bloch空间的刻画
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作者 陈娇 胡春英 《华侨大学学报(自然科学版)》 2025年第4期476-480,共5页
利用Schwarz-Pick引理,得到上半平面上Bloch空间的性质。给出0<α≤2条件下上半平面上α-Bloch空间的一个刻画,并借助具体实例验证结论的正确性。结果表明:文中结果将已有的有界区域上的相应结果推广至无界区域上。
关键词 上半平面 BLOCH空间 Α-BLOCH函数 Α-BLOCH空间
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中国综合气象观测系统的业务发展 被引量:1
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作者 张鹏 李锐 +30 位作者 赵坤 王东晓 王劲松 雷勇 夏祥鳌 咸迪 陈玉宝 吴蕾 赵培涛 郭启云 杨荣康 李翠娜 颜鹏 刘超 王鑫 桂华侨 刘磊 关敏 黄浩 何建新 刘黎平 王宾宾 孙业乐 王一楠 黄勇 胡雯 李柏 王自发 马耀明 刘建国 傅云飞 《气象学报》 北大核心 2025年第3期729-760,共32页
气象观测技术是现代气象科学的基石,推动了学科的发展和业务的进步。20世纪20年代,在中国近代气象科学形成初期,老一辈气象学家就提出了“谋气象学术之进步与测候事业之发展”的中国气象学会宗旨。中国气象观测系统经历了从无到有、从... 气象观测技术是现代气象科学的基石,推动了学科的发展和业务的进步。20世纪20年代,在中国近代气象科学形成初期,老一辈气象学家就提出了“谋气象学术之进步与测候事业之发展”的中国气象学会宗旨。中国气象观测系统经历了从无到有、从人工到自动化、从地面到空间的跨越式发展,已经形成了较为完善的地面观测、高空探测、卫星遥感等多元化的业务观测体系。在这个过程中,科学技术的进步推动了气象观测的不断发展,使得天气预报的准确率和及时性得到了显著提高。从地面气象观测、高空气象探测、海洋气象观测、空间天气观测、天气雷达、气象卫星、地基和空基遥感系统等7个方面概述中国气象观测系统业务的发展历程、现状以及未来的发展趋势。气象观测试验作为气象探测技术发展、探测方法研究、探测装备体系建设的重要创新驱动力在中国观测系统升级换代中发挥了重要的先导和技术支撑作用。概要介绍了中国多源综合观测与大型试验情况。气象观测系统不仅仅是对现有工程技术的应用,更是一个充满未知科学问题、技术挑战和应用领域发展的学科分支。随着观测技术的更新换代,更高精度的传感器和更先进的遥感设备的应用,中国现有的观测设备需要不断更新以保持技术的前沿性和数据的准确性。气象观测系统正在朝着智能化、立体化和全球化的方向发展,大数据、人工智能、量子科技等前沿技术将在未来气象观测系统发展中扮演重要的角色。 展开更多
关键词 综合气象观测 业务发展 地面气象观测 高空气象探测 海洋气象观测 空间天气观测 天气雷达 气象卫星 地基 和空基遥感系统 多源综合观测与大型试验
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基于留轨末子级的空间量子通信技术验证模式
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作者 许华醒 张平 +3 位作者 吴俊杰 王昌雷 王少华 魏然 《国防科技》 2025年第4期40-45,共6页
空间量子通信由科学实验向装备推进,需要开展大量航天验证工作。利用当前我国航天任务持续高密度发射的有利条件,提出基于留轨末子级的空间量子通信技术验证模式。该模式具有搭载机会多、成本低、验证相对充分、支持组网验证等优势。从... 空间量子通信由科学实验向装备推进,需要开展大量航天验证工作。利用当前我国航天任务持续高密度发射的有利条件,提出基于留轨末子级的空间量子通信技术验证模式。该模式具有搭载机会多、成本低、验证相对充分、支持组网验证等优势。从系统、器件、组件3个层面对空间量子通信开展搭载验证进行详细分析。通过“航班化”“小步快走”的方式搭建留轨末子级平台后,可按照战略步骤完成系列在轨实飞验证,加快空间量子通信形成应用。 展开更多
关键词 空间量子通信 留轨末子级 量子通信载荷
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