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New Method for Estimating Daily Global Solar Radiation over Sloped Topography in China

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Advances in Atmospheric Sciences 2018年第3期35卷 285-295页

作者： Guoping shi Xinfa qiu Yan ZENG School of Geography and Remote Sensing Nanjing University of Information Science and Technology Nanjing 210044 China School of Applied Meteorology Nanjing University of Information Science and Technology Nanjing 210044 China jiangsu Climate Center Nanjing 210009 China

A new scheme for the estimation of daily global solar radiation over sloped topography in China is developed based on the Iqbal model C and MODIS cloud fraction. The effects of topography are determined using a digital elevation model. The scheme is tested using observations of solar radiation at 98 stations in China, and the results show that the mean absolute bias error is 1.51 MJ m-2 d-1 and the mean relative absolute bias error is 10.57%. Based on calculations using this scheme, the distribution of daily global solar radiation over slopes in China on four days in the middle of each season （15 January, 15 April, 15 July and 15 October 2003） at a spatial resolution of 1 km×1 km are analyzed. To investigate the effects of topography on global solar radiation, the results determined in four mountains areas （Tianshan, Kunlun Mountains, Qinling, and Nanling） are discussed, and the typical characteristics of solar radiation over sloped surfaces revealed. In general, the new scheme can produce reasonable characteristics of solar radiation distribution at a high spatial resolution in mountain areas, which will be useful in analyses of mountain climate and planning for agricultural production.

关键词： sloped terrain solar radiation topography geographic information system

An Edge Computing Algorithm Based on Multi-Level Star Sensor Cloud

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Computer Modeling in Engineering & Sciences 2023年第8期136卷 1643-1659页

作者： Siyu Ren shi qiu Keyang Cheng The Open University of Chengdu Major in Computer ApplicationChengdu610000China Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences.Xi’an710119China School of Computer Science and Communication Engineering Jiangsu UniversityZhenjiang212013China

Star sensors are an important means of autonomous navigation and access to space information for *** have been widely deployed in the aerospace *** satisfy the requirements for high resolution,timeliness,and confidentiality of star images,we propose an edge computing algorithm based on the star sensor *** sensors cooperate with each other to forma sensor cloud,which in turn extends the performance of a single *** research on the data obtained by the star sensor has very important research and application ***,a star point extraction model is proposed based on the fuzzy set model by analyzing the star image composition,which can reduce the amount of data ***,a mappingmodel between content and space is constructed to achieve low-rank image representation and efficient ***,the data collected by the wireless sensor is delivered to the edge server,and a differentmethod is used to achieve privacy *** a small amount of core data is stored in edge servers and local servers,and other data is transmitted to the *** show that the proposed algorithm can effectively reduce the cost of communication and storage,and has strong privacy.

关键词： Star-sensing sensor cloud fuzzy set edge computing mapping

Representation Theorem for Generators of Quadratic BSDEs

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Acta Mathematicae Applicatae Sinica 2018年第3期34卷 622-635页

作者： shi-qiu ZHENG Shou-mei LI College of Applied Sciences Beijing University of Technology Beijing 100124 China College of Sciences North China University of Science and TechnologyTangshan 063210 China

In this paper, we establish a general representation theorem for generator of backward stochastic differential equation（BSDE）, whose generator has a quadratic growth in z. As some applications, we obtain a general converse comparison theorem of such quadratic BSDEs and uniqueness theorem, translation invariance for quadratic g-expectation.

关键词： backward stochastic differential equation representation theorem of generator converse comparison theorem g-expectation

Perfluorocarboxylic acids(PFCAs)and perfluoroalkyl sulfonates(PFASs)in surface and tap water around Lake Taihu in China

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Frontiers of Environmental Science & Engineering 2010年第3期4卷 301-310页

作者： Yong qiu He JING Hanchang shi State Key Joint Laboratory of Environmental Simulation and Pollution Control Department of Environmental Science and EngineeringTsinghua UniversityBeijing 100084China

Perfluorinated compounds(PFCs)are ubiquitously distributed in the environment mainly as perfluorocarboxylic acids(PFCAs)and perfluoroalkyl sulfonates(PFASs).In this paper,six PFCAs and two PFASs were quantified in surface and tap water samples from 12 sites around Lake Taihu near Shanghai City in East *** PFCs were perfluorooctanoic acid(PFOA)and perfluorooctane sulfonate(PFOS),of which the concentration ranges were 6.8–206 and 1.2–45 ng·L^(–1),the geometric means were 35.3 and 9.4 ng·L^(–1),and the median(quartile range)values were 31.4(34.4)and 10.4(10.7)ng·L^(–1),*** PFCs were also detected but in much lower concentrations than *** sources of the PFCs were expected to be direct industrial discharges in the Lake Taihu area,and this area was also a possible source of PFCs contaminations in Shanghai district in the *** distributions were found different in the upstream,downstream and north part of Lake *** of PFCs in the tap water in Lake Taihu area indicated their exposure to the local people.A brief estimation of the environmental risks by PFCs implied no acute or immediate risks from PFCs to local human health,but chronic risks from PFOA in the tap water should be considered in the downstream regions.

关键词： surface and tap water perfluorocarboxylic acids(PFCAs) perfluoroalkyl sulfonates(PFASs) Lake Taihu area ultra performance liquid chromatography with tandem mass spectrometry(UPLC-MS)

Chalcogen Effect of Atom Substitution on the Properties of Tris(2,4,6-trichlorophenyl)methyl(TTM)Radical

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Chemical Research in Chinese Universities 2023年第2期39卷 197-201页

作者： YANG Yiming qiu Lili shi xueliang Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai200062P.R.China

Luminescent open-shell organic radicals have recently been regarded as one of the most potential materials in organic light-emitting diodes(OLEDs).Herein,we have synthesized two new organic radicals,namely tris{4-[4-(tert-butyl)phenoxy]-2,6-dichlorophenyl}methane radical(TTM-O)and tris(4-{[4-(tert-butyl)-phenyl]thio}-2,6-dichlorophenyl)methane radical(TTM-S),by the substitution of chalcogen atom elements at the para position of conventional tris(2,4,6-trichlorophenyl)methyl(TTM)radical ***,both TTM-O and TTM-S exhibited significantly enhanced photostability compared with the unsubstituted TTM radical ***,the chalcogen atom also had a crucial impact on the photoluminescence quantum yield(PLQY)of the radicals,i.e.,the PLQY of TTM-S was greatly enhanced compared to TTM radical while TTM-O was nearly ***,TTM-S showed intense PLQY of 37.54%and 185-fold longer photostability than that in cyclohexane solution of TTM.

关键词： Luminescent organic radical Chalcogen atom effect Photoluminescence quantum yield(PLQY)

ORIGIN OF THE REPULSIVE CORE OF NUCLEAR FORCE

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Chinese Physics Letters 1990年第11期7卷 489-492页

作者： xu Xiaoming qiu Xijun Institute of Nuclear Research Academia SinicaShanghai 201800

A soliton model for a baryon is extended to study nucleon-nucleon interaction by virtue of the relativistic two-quark-cluster theory・A repulsive core is obtained mainly due to the one ghtoji exchange interaction and quark exchange between two *** this connexion the relativistic effect of quark motion must be considered for producing the repulsive core.

关键词： quark relativistic exchange

Reciprocal translation between SAR and optical remote sensing images with cascaded-residual adversarial networks

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Science China(Information Sciences) 2021年第2期64卷 154-168页

作者： shilei FU Feng xu Ya-qiu JIN Key Lab for Information Science of Electromagnetic Waves (MoE) Fudan University

Despite the advantages of all-weather and all-day high-resolution imaging, synthetic aperture radar(SAR) images are much less viewed and used by general people because human vision is not adapted to microwave scattering phenomenon. However, expert interpreters can be trained by comparing side-byside SAR and optical images to learn the mapping rules from SAR to optical. This paper attempts to develop machine intelligence that is trainable with large-volume co-registered SAR and optical images to translate SAR images to optical version for assisted SAR image interpretation. Reciprocal SAR-optical image translation is a challenging task because it is a raw data translation between two physically very different sensing modalities. Inspired by recent progresses in image translation studies in computer vision,this paper tackles the problem of SAR-optical reciprocal translation with an adversarial network scheme where cascaded residual connections and hybrid L1-GAN loss are employed. It is trained and tested on both spaceborne Gaofen-3(GF-3) and airborne Uninhabited Airborne Vehicle Synthetic Aperture Radar(UAVSAR) images. Results are presented for datasets of different resolutions and polarizations and compared with other state-of-the-art methods. The Frechet inception distance(FID) is used to quantitatively evaluate the translation performance. The possibility of unsupervised learning with unpaired/unregistered SAR and optical images is also explored. Results show that the proposed translation network works well under many scenarios and it could potentially be used for assisted SAR interpretation.

关键词： synthetic aperture radar generative adversarial network (GAN) image translation cascaded residual connection Frechet inception distance

SYNTHESIS　OF　BLOCK　COPOLYMERS　OF　STYRENE　AND　N－（p－SUBSTITUTED　PHENYL）　MALEIMIDES　BY　ANIONIC　POLYMERIZATION

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Chinese Chemical Letters 1996年第4期7卷 367-370页

作者： xu, SJ qiu, KY BEIJING UNIV COLL CHEM & MOL ENGNBEIJING 100871PEOPLES R CHINA

The block copolymers were synthesized by anionic pohymerization via two steps reaction. First, styrene was initiated by n-butyl lithium, then maleimides were added into the living styrene system to obtain block copolymers. 1H-NMR and FT-IR measurements indicated that block coplymers bad been formed From the esults of thermogravimetric, it could be concluded that the block copolymer had a much better thermal stability than random copolymers predared by radical polymerization. Also the surface hydrophilicities of the two kinds of copolymers were compared.

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SIMULATION OF SEDIMENT-LADEN FLOW BY DEPTH-AVERAGED MODEL BASED ON UNSTRUCTURED COLLOCATED GRID

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Journal of Hydrodynamics 2007年第4期19卷 525-532页

作者： LIU shi-he LUO qiu-shi MEI Jun-ya School of Water Resource and Hydropower Wuhan University Wuhan 430072 China

The 2-D depth-averaged mathematical model for sediment-laden flows has been widely used in river control and other related engineering problems, and now it is usually solved on structured grids. Since the natural river is usually very complicated in plane boundary, and unstructured grids are more attractive in solving the problems with complicated domains, the following questions about solving 2-D depth-averaged model were discussed in this article：（1） a modified Bowyer algorithm was suggested to generate unstructured grids for natural rivers, （2） the Finite Volume Method （FVM） is employed to discretize the governing equations of the 2-D depth-averaged model and an implicit scheme was suggested with unstructured collocated grids, （3） the observed hydrological data of the Chenglingji Reach in the Yangtze River are used for verification of the presented method It seems that the suggested numerical scheme works very well, and the simulation results of both hydraulic characteristics and river bed deformation are in good agreement with the observed ones.

关键词： Bowyer algorithm unstructured grid SIMPLE algorithm