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Closed Range Composition Operators on a General Family of Function Spaces
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作者 M.A.Bakhit 《Analysis in Theory and Applications》 CSCD 2016年第3期215-231,共17页
In this paper, necessary and sufficient conditions for a closed range composition operator CФ on the general family of holomorphic function spaces F(p,q,s) and more generally on α-Besov type spaces F(p,αp-2,s) ... In this paper, necessary and sufficient conditions for a closed range composition operator CФ on the general family of holomorphic function spaces F(p,q,s) and more generally on α-Besov type spaces F(p,αp-2,s) are given. We give a Carleson measure characterization on F (p, αp - 2, s) spaces, then we indicate how Carleson measures can be used to characterize boundedness and compactness of CФ on F(p,q,s) and F(p,αp- 2,s) spaces. 展开更多
关键词 Composition operators F(p q s) spaces closed range Carleson measure Bloch space Bergman type space
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SOME PROPERTIES OF THE INTEGRATION OPERATORS ON THE SPACES F(p,q,s)
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作者 陈家乐 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期173-188,共16页
We study the closed range property and the strict singularity of integration operators acting on the spaces F(p,pα-2,s).We completely characterize the closed range property of the Volterra companion operator I_(g)on ... We study the closed range property and the strict singularity of integration operators acting on the spaces F(p,pα-2,s).We completely characterize the closed range property of the Volterra companion operator I_(g)on F(p,pα-2,s),which generalizes the existing results and answers a question raised in[A.Anderson,Integral Equations Operator Theory,69(2011),no.1,87-99].For the Volterra operator J_(g),we show that,for 0<α≤1,J_(g)never has a closed range on F(p,pα-2,s).We then prove that the notions of compactness,weak compactness and strict singularity coincide in the case of J_(g)acting on F(p,p-2,s). 展开更多
关键词 integration operator closed range property strict singularity
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Direct and Reverse Carleson Conditions on Generalized Weighted Bergman-Orlicz Spaces
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作者 Waleed Al-Rawashdeh 《Analysis in Theory and Applications》 CSCD 2017年第3期287-300,共14页
Let D be the open unit disk in the complex plane C. For a〉 -1, let dAa(z)=(1 +a) (1 -|z}^2) ^a da(z)be the weighted Lebesgue measure on ]D. For a positive function ω ∈ L^1(D,dAa), the generalized weight... Let D be the open unit disk in the complex plane C. For a〉 -1, let dAa(z)=(1 +a) (1 -|z}^2) ^a da(z)be the weighted Lebesgue measure on ]D. For a positive function ω ∈ L^1(D,dAa), the generalized weighted Bergman-Orlicz spaceA^ψω(D,dAa)is||f||ω^ψ=∫Dψ|F(z)|ω(z)dA^(z) 〈 ∞,where q; is a strictly convex Orlicz function that satisfies other technical hypotheses. Let G be a measurable subset of D, we say G satisfies the reverse Carleson condition for A^ψω (D, dAa) if there exists a positive constant C such that ∫Gψ(f(z))ω(z)dAa(z)≥C∫Dψ(|f(z)dAa(z).for all f ∈ .A^ψω (D,dAa). Let μ be a positive Borel measure, we say μ satisfies the direct Carleson condition if there exists a positive constant M such that for all f∈Aψ^ω (D,dAa),∫Dψ(|f(z)|)dμ(z)≤M∫Dψ(|f(z)|)ω(z)dAa(a).In this paper, we study the direct and reverse Carleson condition on the generalized weighted Bergman-Orlicz space Aω^ψ(D,dAa).We present conditions on the set G such that'the reverse Carleson condition'holds. "Moreover, we give a sufficient condition for the finite positive Borel measure μ to satisfy the direct carleson condition on the generalized weighted Bergman-Orlicz spaces. 展开更多
关键词 Orlicz function global ?2-condition reverse Carleson condition Direct Carleson condition closed range Pseudohyperbolic disks Orlicz spaces weighted Bergman spaces generalized weighted Bergman-Orlicz spaces
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Seamless integration of above-and undercanopy unmanned aerial vehicle laser scanning for forest investigation 被引量:1
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作者 Yunsheng Wang Antero Kukko +8 位作者 Eric Hyyppä Teemu Hakala Jiri Pyörälä Matti Lehtomäki Aimad El Issaoui Xiaowei Yu Harri Kaartinen Xinlian Liang Juha Hyyppä 《Forest Ecosystems》 SCIE CSCD 2021年第1期124-138,共15页
Background:Current automated forest investigation is facing a dilemma over how to achieve high tree-and plotlevel completeness while maintaining a high cost and labor efficiency.This study tackles the challenge by exp... Background:Current automated forest investigation is facing a dilemma over how to achieve high tree-and plotlevel completeness while maintaining a high cost and labor efficiency.This study tackles the challenge by exploring a new concept that enables an efficient fusion of aerial and terrestrial perspectives for digitizing and characterizing individual trees in forests through an Unmanned Aerial Vehicle(UAV)that flies above and under canopies in a single operation.The advantage of such concept is that the aerial perspective from the above-canopy UAV and the terrestrial perspective from the under-canopy UAV can be seamlessly integrated in one flight,thus grants the access to simultaneous high completeness,high efficiency,and low cost.Results:In the experiment,an approximately 0.5 ha forest was covered in ca.10 min from takeoff to landing.The GNSS-IMU based positioning supports a geometric accuracy of the produced point cloud that is equivalent to that of the mobile mapping systems,which leads to a 2–4 cm RMSE of the diameter at the breast height estimates,and a 4–7 cm RMSE of the stem curve estimates.Conclusions:Results of the experiment suggested that the integrated flight is capable of combining the high completeness of upper canopies from the above-canopy perspective and the high completeness of stems from the terrestrial perspective.Thus,it is a solution to combine the advantages of the terrestrial static,the mobile,and the above-canopy UAV observations,which is a promising step forward to achieve a fully autonomous in situ forest inventory.Future studies should be aimed to further improve the platform positioning,and to automatize the UAV operation. 展开更多
关键词 FOREST In situ INVENTORY Above canopy Under canopy Unmanned aerial vehicle Laser scanning Point cloud Close range remote sensing
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Simulation of the landform change process on a purple soil slope due to tillage erosion and water erosion using UAV technology 被引量:1
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作者 YANG Chao SU Zheng-an +6 位作者 FAN Jian-rong FANG Hai-dong SHI Liang-tao ZHANG Jian-hui HE Zhou-yao ZHOU Tao WANG Xiao-yi 《Journal of Mountain Science》 SCIE CSCD 2020年第6期1333-1344,共12页
Both tillage erosion and water erosion are severe erosional forms that occur widely on sloping agricultural land.However,previous studies have rarely considered the process of landform change due to continuous simulat... Both tillage erosion and water erosion are severe erosional forms that occur widely on sloping agricultural land.However,previous studies have rarely considered the process of landform change due to continuous simulation experiments of alternating tillage erosion and water erosion.To identify such changes,we applied a scouring experiment(at a 60 L min-1 water discharge rate based on precipitation data from the local meteorological station and the catchment area in the Yuanmou County,Yunnan Province,China)and a series of simulated tillage experiments where plots were consecutively tilled 5,10,and 15 times in rotation(representing 5 yr,10 yr,and 15 yr of tillage)at slope gradients of 5°,10°,and 20°.Close-range photogrammetry(CRP)employing an unmanned aerial vehicle(UAV)and a real-time kinematic global positioning system(RTK-GPS)was used to measure landform changes,and highresolution digital elevation models(DEMs)were generated to calculate net soil loss volumes.Additionally,the CRP was determined to be accurate and applicable through the use of erosion pins.The average tillage erosion rates were 69.85,131.45,and 155.34 t·hm-2·tillage pass-1,and the average water erosion rates were 1892.52,2961.76,and 4405.93 t·hm-2·h-1 for the 5°,10°,and 20°sloping farmland plots,respectively.The water erosion rates increased as tillage intensity increased,indicating that tillage erosion accelerates water erosion.Following these intensive tillage treatments,slope gradients gradually decreased,while the trend in slope gradients increased in runoff plots at the conclusion of the scouring experiment.Compared to the original plots(prior to our experiments),interactions between tillage and water erosion caused no obvious change in the landform structure of the runoff plots,while the height of all the runoff plots decreased.Our findings showed that both tillage erosion and water erosion caused a pseudo-steady-state landform evolutionary mechanism and resulted in thin soil layers on cultivated land composed of purple soil in China. 展开更多
关键词 Landform change Tillage erosion Water erosion Close range photogrammetry Erosion pins Runoff plot
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Integrated Computer Aided Shoe-Making System
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作者 ZHU Chuanxu LIU Yigong LIU Xiaochun 《Computer Aided Drafting,Design and Manufacturing》 1991年第1期63-72,6,共11页
Shoemaking is one of the areas where CAD/CAM application is rapidly increasing.This paper introduces an integrated computer aided shoemaking system including human foot measuring,last (wooden model)measuring,last CAD/... Shoemaking is one of the areas where CAD/CAM application is rapidly increasing.This paper introduces an integrated computer aided shoemaking system including human foot measuring,last (wooden model)measuring,last CAD/CAM and pattern CAD/CAM.The project was supported by the 7th national economical 5 year plan.High technologies,suh as digital image processing,pattern rcognition,advanced geometrical modeling and a series of sophisticated equipments and devices are ap- plied in this integrated system.Parts of the system have become commercial products. 展开更多
关键词 SHOE-MAKING Digital Photogrammetry Close range Measuring Surface Modeling SKINNING Surface Trimming
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Accurate 3D Target Positioning in Close Range Photogrammetry with Implicit Image Correction 被引量:6
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作者 Zheng Jiandong Zhang Liyana Du Xiaoyu 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2009年第6期649-657,共9页
Accurate three-dimensional (3D) target positioning is of great importance in many industrial applications. Although various methods for reconstructing 3D information from a set of images have been available in the l... Accurate three-dimensional (3D) target positioning is of great importance in many industrial applications. Although various methods for reconstructing 3D information from a set of images have been available in the literature, few of them pay enough attention to the indispensable procedures, such as target extraction from images and image correction having strong influences upon the 3D positioning accuracy. This article puts forward a high-precision ellipse center (target point) extraction method and a new image correction approach which has been integrated into the 3D reconstruction pipeline with a concise implicit model to accurately compensates for the image distortion. The methods are applied to a copyright-reserved close range photogrammetric system. Real measuring experiments and industrial applications have evidenced the proposed methods, which can significantly improve the 3D positioning accuracy. 展开更多
关键词 close range photogrammetry implicit camera model image correction feature extraction
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