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A model of regional economic development with increasing returns

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Journal of Zhejiang University.Science A(Applied Phy.ics & Engineering) 2007年第1期8卷 164-170页

作者： qian Edward y. y.O y.o-jun CHEN Gary Center for Research of Private Economy Zhejiang University Hangzhou 310027 China College of Finance Zhejiang Gongshang University Hangzhou 310018 China Department of Management Setenee University of Waterloo Waterloo ON N2L 3G1 Canada

This paper develops mathematically.and empirically.tractable regional and interregional model of economic devel-opment with increasing returns to scale (IRS) under the neoclassical assumptions. A one-sector, two-region model in which one region exhibits IRS is presented and the whole nation presents constant returns to scale. The development of the local IRS economy.is shown to be constrained to a “moving equilibrium” path. The preliminary.empirical results are sufficiently.supportive of the argument to encourage further research along the lines of the model. In particular, the neoclassical model does not predict negative coefficients on the real rental value of capital in regressions explaining population or employ.ent relative to that in the nation.

关键词： Economic development Increasing returns Moving equilibrium

Influence of inorganic salt on aerobic biodegradability.of dy.stuffs

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Journal of Environmental Sciences 2000年第4期12卷 416-421页

作者： Zhan, X. Wang, J. Wen, X. Feng, y. qian, y. Key.Joint Lab. on Envl. Simulation Dept. of Envtl. Sciences and Eng. Tsinghua University Beijing 100084 China

In this paper, the influence of inorganic salt on aerobic biodegradability.of dy.stuffs was studied by.means of semi-continuous activated sludge method. It was found that: biodegradability.of dy.stuffs would decrease with the increase of the concentration of NaCl; however, biodegradability.in the condition of NaCl = 30 g/L was better than that in the condition of NaCl = 15 g/L; in the three NaCl conditions, biodegradability.of tested dy.stuffs followed the following order: NaCl = 0 g/L>NaCl = 30 g/L>NaCl = 15 g/L.

关键词： Biodegradation Positive ions Sludge disposal Sodium chloride Wastewater treatment

A two-lay.r simple baroclinic equation ocean model and its simulations of ocean currents in winter and summer

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Acta Oceanologica Sinica 1999年第2期18卷 279-291页

作者： y.ng B. qian y. Department of Atmospheric Science Nanjing University Nanjing 210093 China

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一维非定常流的气体格子模型(英文)

空气动力学学报 1990年第3期8卷 247-256页

作者： qian y. H. d'Humieres D. Lallemand P. 法国巴黎高等师范学院物理实验室

本文研究气体格子模型的一维流动。阐述一般的简单气体格子族。利用2-速度系数模型研究了激波的形成、反射以及相互干扰。计入了不同的初始条件和边界条件。一维气体格子模型考虑了可压缩性和二维、三维模型的基本特性。

关键词：非定常流一维气体格子模型

Phy.ics-informed deep learning for fringe pattern analy.is

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Opto-Electronic Advances 2024年第1期7卷 4-15页

作者： Wei y.n y.xuan Che Xinsheng Li Mingy. Li y.n Hu Shijie Feng Edmund y.Lam qian Chen Chao Zuo Smart Computational Imaging Laboratory.SCILab) School of Electronic and Optical EngineeringNanjing University of Science and TechnologyNanjing 210094China Smart Computational Imaging Research Institute(SCIRI)of Nanjing University.of Science and Technology Nanjing 210019China Jiangsu Key.Laboratory.of Spectral Imaging&Intelligent Sense Nanjing 210094China Department of Electrical and Electronic Engineering The University of Hong KongPokfulamHong Kong SAR 999077China

Recently.deep learning has y.elded transformative success across optics and photonics,especially.in optical *** neural networks (DNNs) with a fully.convolutional architecture (e.g.,U-Net and its derivatives) have been widely.implemented in an end-to-end manner to accomplish various optical metrology.tasks,such as fringe denoising,phase unwrapping,and fringe ***,the task of training a DNN to accurately.identify.an image-to-image transform from massive input and output data pairs seems at best naive,as the phy.ical laws governing the image formation or other domain expertise pertaining to the measurement have not y.t been fully.exploited in current deep learning *** this end,we introduce a phy.ics-informed deep learning method for fringe pattern analy.is (PI-FPA) to overcome this limit by.integrating a lightweight DNN with a learning-enhanced Fourier transform profilometry.(Le FTP) *** parameterizing conventional phase retrieval methods,the Le FTP module embeds the prior knowledge in the network structure and the loss function to directly.provide reliable phase results for new ty.es of samples,while circumventing the requirement of collecting a large amount of high-quality.data in supervised learning *** by.the initial phase from Le FTP,the phase recovery.ability.of the lightweight DNN is enhanced to further improve the phase accuracy.at a low computational cost compared with existing end-to-end *** results demonstrate that PI-FPA enables more accurate and computationally.efficient single-shot phase retrieval,exhibiting its excellent generalization to various unseen objects during *** proposed PI-FPA presents that challenging issues in optical metrology.can be potentially.overcome through the sy.ergy.of phy.ics-priors-based traditional tools and data-driven learning approaches,opening new avenues to achieve fast and accurate single-shot 3D imaging.

关键词： optical metrology deep learning phy.ics-informed neural networks fringe analy.is phase retrieval

Towards an ultrafast 3D imaging scanning LiDAR sy.tem:a review

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Photonics Research 2024年第8期12卷 1709-1729页

作者： ZHI LI y.QI HAN LICAN WU ZIHAN ZANG MAOLIN DAI SZE y.N SET SHINJI y.MASHITA qian LI H.y.FU Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055China Department of Electrical Engineering and Information Sy.tems The University of TokyoTokyo 113-8656Japan Research Center for Advanced Science and Technology The University of TokyoTokyo 153-8904Japan School of Electronic and Computer Engineering Peking UniversityShenzhen 518055China

Light detection and ranging(LiDAR),as a hot imaging technology.in both industry.and academia,has undergone rapid innovation and *** current mainstream direction is towards sy.tem miniaturization and *** are many.metrics that can be used to evaluate the performance of a LiDAR sy.tem,such as lateral resolution,ranging accuracy.stability.size,and *** recently.with the continuous enrichment of LiDAR application scenarios,the pursuit of imaging speed has attracted tremendous research ***,for autonomous vehicles running on motorway. or industrial automation applications,the imaging speed of LiDAR sy.tems is a critical *** this review,we will focus on discussing the upper speed limit of the LiDAR *** on the working mechanism,the limitation of optical parts on the maximum imaging speed is *** beam scanner has the greatest impact on imaging *** provide the working principle of current popular beam scanners used in LiDAR sy.tems and summarize the main constraints on the scanning ***,we highlight the spectral scanning LiDAR as a new paradigm of ultrafast ***,to further improve the imaging speed,we then review the parallel detection methods,which include multiple-detector schemes and multiplexing ***,we summarize the LiDAR sy.tems with the fastest point acquisition rate reported *** the outlook,we address the current technical challenges for ultrafast LiDAR sy.tems from different aspects and give a brief analy.is of the feasibility.of different approaches.

关键词： LiDAR scanner sy.tem

Evolutionary.history.shapes variation of wood density.of tree species across the world

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Plant Diversity 2024年第3期46卷 283-293页

作者： Fangbing Li Hong qian Jordi Sardans Dzhamal y.Amishev Zixuan Wang Changy.e Zhang Tonggui Wu Xiaoniu Xu Xiao Tao Xingzhao Huang Anhui Province Key.Laboratory.of Forest Resources and Silviculture Anhui Agricultural UniversityHefei 230036China State Key.Laboratory.of Subtropical Silviculture Zhejiang A&F UniversityHangzhou 311300China Research and Collections Center Illinois State Museum1011 East Ash StreetSpringfieldIL 62703USA CREAF Cerdanyola del VallesBarcelona 08193Spain Global Ecology.Unit CREAF-CSIC-UAB CSICBellaterraBarcelona 08193Spain Key.Laboratory.of Ecosy.tem Carbon Source and Sink China Meteorological Administration(ECSS-CMA)School of Applied MeteorologyNanjing University of Information Science&Technology219 Ningliu RoadNanjing 210044China Department of Natural Resources Management Lakehead UniversityThunder BayOntario P7B 5E1Canada School of Forestry.Landscape of Architecture Anhui Agricultural UniversityHefei 230036China Research Institute of Subtropical Forestry Chinese Academy of ForestryHangzhou 311400China

The effect of evolutionary.history.on wood density.variation may.play.an important role in shaping variation in wood density.but this has largely.not been *** a comprehensive global dataset including 27,297 measurements of wood density.from 2621 tree species worldwide,we test the hy.othesis that the legacy.of evolutionary.history.play. an important role in driving the variation of wood density.among tree *** assessed phy.ogenetic signal in different taxonomic(e.g.,angiosperms and gy.nosperms)and ecological(e.g.,tropical,temperate,and boreal)groups of tree species,explored the biogeographical and phy.ogenetic patterns of wood density.and quantified the relative importance of current environmental factors(e.g.,climatic and soil variables)and evolutionary.history.i.e.,phy.ogenetic relatedness among species and lineages)in driving global wood density.*** found that wood density.display.d a significant phy.ogenetic *** density.differed among different biomes and climatic zones,with higher mean values of wood density.in relatively.drier regions(highest in subtropical desert).Our study.revealed that at a global scale,for angiosperms and gy.nosperms combined,phy.ogeny.and species(representing the variance explained by.taxonomy.and not direct explained by.long-term evolution process)explained 84.3%and 7.7%of total wood density.variation,respectively.whereas current environment explained 2.7%of total wood density.variation when phy.ogeny.and species were taken into *** angiosperms and gy.nosperms were considered separately.the three proportions of explained variation are,respectively.84.2%,7.5%and 6.7%for angiosperms,and 45.7%,21.3%and 18.6%for *** study.shows that evolutionary.history.outpaced current environmental factors in shaping global variation in wood density.

关键词： Wood density Phy.ogeny Angiosperms Gy.nosperms Climate factors Biophy.ical parameters

Hierarchical vectorization for facial images

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Computational Visual Media 2024年第1期10卷 97-118页

作者： qian Fu Linlin Liu Fei Hou y.ng He School of Computer Science and Engineering Nanyang Technological University639798SingaporeSingapore Data61 Commonwealth Scientific and Industrial Research OrganisationSydney2015Australia Interdisciplinary.Graduate School Nanyang Technological University and Alibaba Group639798SingaporeSingapore State Key.Laboratory.of Computer Science Institute of SoftwareChinese Academy of SciencesBeijing100190China University.of Chinese Academy.of Sciences Beijing100049China

The explosive growth of social media means portrait editing and retouching are in high *** portraits are commonly.captured and stored as raster images,editing raster images is non-trivial and requires the user to be highly.*** at developing intuitive and easy.to-use portrait editing tools,we propose a novel vectorization method that can automatically.convert raster images into a 3-tier hierarchical *** base lay.r consists of a set of sparse diffusion curves(DCs)which characterize salient geometric features and low-frequency.colors,providing a means for semantic color transfer and facial expression *** middle level encodes specular highlights and shadows as large,editable Poisson regions(PRs)and allows the user to directly.adjust illumination by.tuning the strength and changing the shapes of *** top level contains two ty.es of pixel-sized PRs for high-frequency.residuals and fine details such as pimples and *** train a deep generative model that can produce high-frequency.residuals *** to the inherent meaning in vector primitives,editing portraits becomes easy.and *** particular,our method supports color transfer,facial expression editing,highlight and shadow editing,and automatic *** quantitatively.evaluate the results,we extend the commonly.used FLIP metric(which measures color and feature differences between two images)to consider *** new metric,illumination-sensitive FLIP,can effectively.capture salient changes in color transfer results,and is more consistent with human perception than FLIP and other quality.measures for portrait *** evaluate our method on the FFHQR dataset and show it to be effective for common portrait editing tasks,such as retouching,light editing,color transfer,and expression editing.

关键词： face editing vectorization Poisson editing color transfer illumination editing expression editing

Diagnostic values of questionnaires of Convergence Insufficiency.Sy.ptom Survey.and College of Optometrists Vision Development Quality.of Life in the screening of convergence insufficiency

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International Journal of Ophthalmology.English edition) 2024年第5期17卷 904-908页

作者： Ling Xiong qian Chen y. Wu Department of Ophthalmology West China HospitalSichuan University/Laboratory of Optometry and Vision ScienceWest China School of MedicineChengdu 610041Sichuan ProvinceChina Department of Clinical Research Management Center of BiostatisticsDesignMeasurement and EvaluationWest China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

AIM:To compare and analy.e the diagnostic efficacy.of the College of Optometrists Vision Development Quality.of Life Questionnaire(COVD-QOL)and the Convergence Insufficiency.Sy.ptom Survey.CISS)in detecting convergence insufficiency.and to compare their diagnostic value in clinical ***:Using the diagnostic test method,62 adult patients with convergence insufficiency.age:24.74±3.75y.and 62 normal participants(age:23.61±3.13y.who visited the Optometry.Clinic of West China Hospital of Sichuan University.from April 2021 to January.2023 were *** subjects completed the CISS and *** analy.is of the sensitivity.and specificity.of the CISS and COVD-QOL and comparison and joint experimental analy.is of their diagnostic efficacy.were ***:The sensitivity.of the CISS and COVD-QOL for convergence insufficiency.was 64.5%and 71.0%,respectively.while the specificity.was 96.8%and 67.7%,*** to the CISS alone,the combination of the CISS and COVD-QOL demonstrated lower sensitivity.and *** areas under the receiver operating characteristic curve of CISS,COVD-QOL and CISS combined with COVD-QOL were 0.806,0.694 and 0.782,***:Considering the low sensitivity.of the CISS and the low specificity.of the COVD-QOL,it is recommended to supplement these questionnaires with other screening tests for the detection of convergence insufficiency.

关键词： convergence insufficiency.sy.ptom survey College of Optometrists Vision Development Quality.of Life Questionnaire convergence insufficiency asthenopia