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数字普惠金融与农业绿色发展——基于金融约束缓解的视角

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农村金融研究 2024年第2期 39-57页

作者：王芳毛静宜张晓静李奇锴蔡起华郑州大学商学院

在农业生态化转型与可持续发展的背景下,农业绿色发展是实现农业高质量发展的现实路径,而作为新型金融模式的数字普惠金融,是打破农村金融困境的有效工具,已经成为农业绿色发展的重要驱动力。因此,论文利用中国2011-2020年30个省级面板... 详细信息

在农业生态化转型与可持续发展的背景下,农业绿色发展是实现农业高质量发展的现实路径,而作为新型金融模式的数字普惠金融,是打破农村金融困境的有效工具,已经成为农业绿色发展的重要驱动力。因此,论文利用中国2011-2020年30个省级面板数据,从金融约束缓解的视角,深入研究数字普惠金融对农业绿色发展的影响效应。研究发现:1.2011-2020年,农业绿色发展水平及其分指数,整体呈现上升趋势,但是,各区域间的农业绿色发展差异较大;2.数字普惠金融对农业绿色发展具有显著的促进作用,其中,数字普惠金融使用深度对农业绿色发展的影响程度最大;3.数字普惠金融能够通过缓解金融约束推动农业绿色发展;4.从农业重要性角度而言,数字普惠金融对粮食主产区农业绿色发展的影响程度最大,且其在粮食主产区和非粮食主产区中,均能通过缓解金融约束促进农业绿色发展。从区域差异性角度来看,数字普惠金融对农业绿色发展的影响程度,沿东部、中部向西部递减,且其均能通过缓解金融约束来促进东部和西部的农业绿色发展。为加快农业生产方式转型,推动农业绿色发展的进程,论文提出完善农村数字普惠金融市场、缩小区域“数字鸿沟”、增强数字普惠金融的农业绿色发展效能等政策建议。

关键词：数字普惠金融农业绿色发展金融约束缓解双向固定效应模型

基于多模态共享网络的自监督语音-人脸跨模态关联学习方法

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科学技术与工程 2024年第7期24卷 2804-2812页

作者：李俊屿卜凡亮谭林周禹辰毛璟仪中国人民公安大学信息网络安全学院北京100038 公安部第一研究所北京100048

现有的语音-人脸跨模态关联学习方法在语义关联和监督信息方面仍然面临挑战,尚未充分考虑语音与人脸之间的语义信息交互。为解决这些问题,提出一种基于多模态共享网络的自监督关联学习方法。首先,将语音和人脸模态的特征映射到单位球面... 详细信息

现有的语音-人脸跨模态关联学习方法在语义关联和监督信息方面仍然面临挑战,尚未充分考虑语音与人脸之间的语义信息交互。为解决这些问题,提出一种基于多模态共享网络的自监督关联学习方法。首先,将语音和人脸模态的特征映射到单位球面,构建一个公共的特征空间;接着,通过多模态共享网络的残差块来挖掘复杂的非线性数据关系,并利用其中权重共享的全连接层来增强语音与人脸特征向量之间的关联性;最后,使用K均值聚类算法生成的伪标签作为监督信号来指导度量学习,从而完成4种跨模态关联学习任务。实验结果表明,本文提出的方法在语音-人脸跨模态验证、匹配和检索任务上均取得了良好的效果,多项评价指标相较于现有基线方法提升1%~4%的准确率。

关键词：语音-人脸跨模态多模态共享网络伪标签关联学习

Numerical study of submerged bending vegetation under unidirectional flow

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Water Science and Engineering 2024年第1期17卷 92-100页

作者： Pei-pei Zhang yi-qing Gong Ken Vui Chua Jie Dai jing-qiao mao College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China Institute of Water Science and Technology Hohai UniversityNanjing 210098China School of Engineering Cardiff UniversityCardiff CF243AAUK

Submerged vegetation commonly grows and plays a vital role in aquatic ecosystems,but it is also regarded as a barrier to the passing *** simulations of flow through and over submerged vegetation were carried out to investigate the effect of vegetation density on flow *** simulations were computationally set up to replicate flume experiments,in which vegetation was mimicked with flexible plastic *** fluid-structure interaction between flow and flexible vegetation was solved by coupling the two modules of the COMSOL *** cases with different vegetation densities were simulated,and the results were successfully validated against the experimental *** contours of the simulated time-averaged streamwise velocity and Reynolds stress were extracted to highlight the differences in mean and turbulent flow *** turbulence intensity was found to be more sensitive to vegetation density than the time-averaged *** developing length increased with the spacing between *** snapshots of the bending vegetation under instantaneous velocity and vorticity revealed that flexible vegetation responded to the effects of eddies in the shear layer by swaying *** first two rows of vegetation suffered stronger approaching flow and were prone to more streamlined *** addition,the origin of tip vortices was investigated via the distribution of *** results reveal the variation of flow properties with bending submerged vegetation and provide useful reference for optimizationofrestorationprojects.

关键词： Computational fluid dynamics Fluid-structure interaction Turbulence Flexible and submerged vegetation

Combination Therapy of Acitretin Capsule and Chinese Herbs for Patients with Lichen Planus Pigmentosus-Inversus

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Chinese Journal of Integrative Medicine 2019年第12期25卷 922-925页

作者： CHEN Yu XUE Liang GUO Dong-jie mao jing-yi WU Min-feng XU Rong LI Xin LI Bin LI Fu-lun Department of Dermatology Yueyang Hospital of Integrated Traditional Chinese and Western MedicineAffiliated to Shanghai University of Traditional Chinese MedicineShanghai(200437)China Department of Burn and Plastic Surgery the Seventh People's Hospital of Integrated Traditional Chinese and Western MedicineAffiliated to Shanghai University of Traditional Chinese MedicineShanghai(200137)China

Lichen planus pigmentosus-inversus(LPPI)is a relatively uncommon variant of lichen planus(LP),characterized by mottled pigmentation of bluish,black or grey color on the flexural folds with or without *** was first described by Pock,et al(1)in *** present,there are only 27 cases of the disease reported from 13 reports internationally.(2)As very few cases about LPPI are reported,the diagnosis and selection of therapeutic scheme are fairly difficult for ***,we report 3 cases who presented with LPPI,obtaining good results after Chinese medicine(CM)*** cases have typical clinical and histological ***,a case of melanosis is reported,which has similar clinic manifestation and is differentiated by pathological *** report was authorized by all patients.

关键词： diagnosis Therapy Patients

Free radicals trigger the closure of open pores in lignin-derived hard carbons toward improved sodium-storage capacity

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Journal of Energy Chemistry 2024年第7期94卷 551-559页

作者： Wen-Jun Ji Zong-Lin yi Ming-Xin Song Xiao-Qian Guo yi-Lin Wang yi-Xuan mao Fang-Yuan Su jing-Peng Chen Xian-Xian Wei Li-jing Xie Cheng-Meng Chen CAS Key Laboratory of Carbon Materials Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001ShanxiChina University of Chinese Academy of Sciences Beijing 100049China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Environment and Safety Taiyuan University of Science and TechnologyTaiyuan 030001ShanxiChina

The chemical activation of various precursors is effective for creating additional closed pores in hard carbons for sodium ***,the formation mechanism of closed pores under the influence of pore-forming agents is not well ***,an effective chemical activation followed by a high-temperature self-healing strategy is employed to generate interconnected closed pores in lignin-derived hard carbon(HCs).By systematic experimental design combined with electron paramagnetic res-onance spectroscopy,it can be found that the content of free radicals in the carbon matrix influences the closure of open pores at high *** high activation temperature(>700 C)leads to a low free radical concentration,making it difficult to achieve self-healing of open pores at high *** activation at 700°C,a balance between pore making and self-healing is achieved in the final hard carbon.A large number of free radicals triggers rapid growth and aggregation of carbon microcrys-tals,blocking pre-formed open micropores and creating additional interconnected closed pores in as-obtained hard *** a result,the optimized carbon anode(LK-700-1300)delivers a high reversible capacity of 330.8 mA h g^(-1) at 0.03 A g^(-1),which is an increase of 86 mA h g^(-1) compared to the pristine lignin-derived carbon anode(L-700-1300),and exhibits a good rate performance(202.1 mA h g^(-1) at 1 A g^(-1)).This work provides a universal and effective guidance for tuning closed pores of hard carbons from otherprecursors.

关键词： Hard carbon Chemical activation Free radical Self-healing Closed pores Sodium ion batteries

A stable staggered-grid finite-difference scheme for acoustic modeling beyond conventional stability limit

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Petroleum Science 2024年第1期21卷 182-194页

作者： jing-yi Xu Yang Liu National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing 102249China China University of Petroleum(Beijing) Karamay CampusKaramay 834000XinjiangChina

Staggered-grid finite-difference(SGFD)schemes have been widely used in acoustic wave modeling for geophysical *** improved methods are proposed to enhance the accuracy of numerical ***,these methods are inevitably limited by the maximum Courant-Friedrichs-Lewy(CFL)numbers,making them unstable when modeling with large time sampling intervals or small grid *** solve this problem,we extend a stable SGFD scheme by controlling SGFD dispersion relations and maximizing the maximum CFL ***,to improve modeling stability,we minimize the error between the FD dispersion relation and the exact relation in the given wave-number region,and make the FD dispersion approach a given function outside the given wave-number area,thus breaking the conventional limits of the maximum CFL ***,to obtain high modeling accuracy,we use the SGFD scheme based on the Remez algorithm to compute the FD *** addition,the hybrid absorbing boundary condition is adopted to suppress boundary reflections and we find a suitable weighting coefficient for the proposed *** derivation and numerical modeling demonstrate that the proposed scheme can maintain high accuracy in the modeling process and the value of the maximum CFL number of the proposed scheme can exceed that of the conventional SGFD scheme when adopting a small maximum effective wavenumber,indicating that the proposed scheme improves stability during the modeling.

关键词： Acoustic wave Staggered-grid finite-difference(SGFD) modeling Courant-friedrichs-lewy(CFL)number Stability

Parametric resonance of axially functionally graded pipes conveying pulsating fluid

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 239-260页

作者： Jie jing Xiaoye mao Hu DING Liqun CHEN Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechanoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200444China Shanghai Institute of Aircraft Mechanics and Control Shanghai 200092China

Based on the generalized Hamilton's principle,the nonlinear governing equation of an axially functionally graded(AFG)pipe is *** non-trivial equilibrium configuration is superposed by the modal functions of a simply supported *** the direct multi-scale method,the response and stability boundary to the pulsating fluid velocity are solved analytically and verified by the differential quadrature element method(DQEM).The influence of Young's modulus gradient on the parametric resonance is investigated in the subcritical and supercritical *** general,the pipe in the supercritical region is more sensitive to the pulsating *** nonlinearity changes from hard to soft,and the non-trivial equilibrium configuration introduces more frequency components to the ***,the increasing Young's modulus gradient improves the critical pulsating flow velocity of the parametric resonance,and further enhances the stability of the *** addition,when the temperature increases along the axial direction,reducing the gradient parameter can enhance the response *** work further complements the theoretical analysis of pipes conveying pulsating fluid.

关键词： pipe conveying fluid axially functionally graded supercritical resonance multi-scale method parametric resonance

Dynamic steric confinement effect expands the frontier of Cu-catalyzed asymmetric propargylic aminations

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Science China Chemistry 2024年第10期67卷 3181-3183页

作者： Peng Chen mao-mao Zhang Wen-jing Xiao Liang-Qiu Lu Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction Ministry of EducationCollege of ChemistryCentral China Normal University Wuhan Institute of Photochemistry and Technology State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics (LICP)Chinese Academy of Sciences School of Chemistry and Chemical Engineering Henan Normal University

Chiral α-tertiary amines and related azacycles are commonly found in many natural products, pharmaceuticals and agrochemicals [1]. Copper-catalyzed asymmetric propargylic amination(APA) reactions have been established as a reliable method to access enantio-enriched propargylic amines,largely due to the seminal contribution of Nishibayashi et al.[2] and van Maarseveen et al. [3] in 2008.

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Cordyceps as potential therapeutic agents for atherosclerosis

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Journal of Integrative Medicine 2024年第2期22卷 102-114页

作者： yi Zhang Si-jing Liu School of Marxism Chengdu University of Traditional Chinese MedicineChengdu 61137Sichuan ProvinceChina College of Medical Technology Chengdu University of Traditional Chinese MedicineChengdu 611137Sichuan ProvinceChina Chongqing Key Laboratory of Sichuan-Chongqing Co-construction for Diagnosis and Treatment of Infectious Diseases with Integrated Chinese and Western Medicine Chengdu University of Traditional Chinese MedicineChengdu 611137Sichuan ProvinceChina

Atherosclerosis is a leading cause of mortality and morbidity *** the challenges in managing atherosclerosis,researchers continue to investigate new treatments and complementary *** is a traditional Chinese medicine that has recently gained attention as a potential therapeutic agent for *** studies have demonstrated the effectiveness of cordyceps in treating atherosclerosis through various pharmacological actions,including anti-inflammatory and antioxidant activities,lowering cholesterol,inhibiting platelet aggregation,and modulating apoptosis or autophagy in vascular endothelial ***,the current misuse of the terms cordyceps and Ophiocordyceps sinensis has caused confusion among researchers,and complicated the current academic research on *** review focuses on the chemical composition,pharmacological actions,and underlying mechanisms contributing to the anti-atherosclerotic effects of cordyceps and the mycelium of Ophiocordyceps *** review provides a resource for the research on the development of new drugs for atherosclerosis from cordyceps.

关键词： Atherosclerosis Cordyceps Ophiocordyceps sinensis