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Rural labor migration and farmers’arrangements of rice production systems in Central China:Insight from the intergenerational division of labor

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Journal of Integrative Agriculture 2024年第9期23卷 3200-3214页

作者： Xue Shen Quanyu Yang Rongjun ao Shengsheng Gong Key Laboratory for Geographical Process Analysis&Simulation of Hubei Province/College of Urban and Environmental Sciences Central China Normal UniversityWuhan 430079China

Rice production is crucial for food security in China,and its relationship with rural labor migration has been studied *** migration in rural China has taken new forms in recent *** has been a discernible trend wherein adult children have started migrating to cities while their elderly parents return to villages to re-engage in on-farm *** phenomenon has notably shaped the intergenerational division of labor(IDL)within ***,it remains to be seen how farmers adjust their rice production systems in response to the *** age of 60 years for employment injury insurance is the eligibility threshold for off-farm employment and is used to obtain a source of exogenous variation in the *** on a representative household survey of 1,752 rice farmers in the Hubei Province of Central China,our fuzzy regression discontinuity analysis reveals that farmers in IDL households are more likely to adopt ratoon rice(RR)than single cropping rice(SR)or double cropping rice(DR).The effect of the IDL varies under different levels of operational scales and specialized agricultural service *** analysis suggests that farmers’arrangements are associated with two potential mechanisms of downward intergenerational *** transfer for urban housing purchases increases RR in IDL households,and time transfer for intergenerational childcare significantly promotes SR in IDL *** study enhances the understanding of the relationship between rural labor migration and rice production in China,providing a reference for adjusting rice production systems to ensure food security.

关键词： labor migration intergenerational division of labor rice production systems fuzzy regression discontinuity Central China

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Europium-bearing organic framework with excellent X-ray scintillating luminescence

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Journal of Rare Earths 2024年第2期42卷 251-255,I0001页

作者： Yugang Zhang Lanhua Chen Xia Wang Wei Liu Shu'ao Wang State Key Laboratory of Radiation Medicine and Protection School for Radiological and Interdisciplinary Sciences(RAD-X)and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education InstitutionsSoochow UniversitySuzhou215123China School of Environmental and Materials Engineering Yantai UniversityYantai264005China

Two europium-bearing organic frameworks,termed as EuTPO-1 and EuTPO-2(H_(3)TPO=tris(4-carboxylphenyI)-phosphineoxide),are reported in this work.A series of characterizations of EuTPO-1and EuTPO-2,such as X-ray crystallography and photoluminescence spectroscopy,was performed to expatiate their structure and physicochemical *** of them are constructed by dimers of the europium-oxygen subunit of [Eu_(2)O_(16)] and TPO *** from high X-ray stopping attenuation and excellent luminescence efficiency,they emit sufficient luminescence when irradiated with ***,they possess stable light outputs when exposed to high humidities and strong radiation dose,outperforming the commercial scintillator CsI:*** result paves the way for developing new scintillator and enriches the compound of europium-bearing organic framework with X-ray scintillating luminescence.

关键词： Metal-organic frameworks Scintillating material Luminescence efficiency Rare earths

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Exploiting sound for emerging applications of extracellular vesicles

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Nano Research 2024年第2期17卷 462-475页

作者： Zhuhao Wu Hongwei Cai Chunhui Tian Zheng ao Lei Jiang Feng Guo Department of Intelligent Systems Engineering Indiana UniversityBloomingtonIN 47405USA

Extracellular vesicles are nano-to micro-scale,membrane-bound particles released by cells into extracellular space,and act as carriers of biomarkers and therapeutics,holding promising potential in translational ***,the challenges remain in handling and detecting extracellular vesicles for disease diagnosis as well as exploring their therapeutic capability for disease ***,we review the recent engineering and technology advances by leveraging the power of sound waves to address the challenges in diagnostic and therapeutic applications of extracellular vesicles and biomimetic *** first introduce the fundamental principles of sound waves for understanding different acoustic-assisted extracellular vesicle *** discuss the acoustic-assisted diagnostic methods including the purification,manipulation,biosensing,and bioimaging of extracellular ***,we summarize the recent advances in acoustically enhanced therapeutics using extracellular vesicles and biomimetic ***,we provide perspectives into current challenges and future clinical applications of the promising extracellular vesicles and biomimetic nanovesicles powered by sound.

关键词： extracellular vesicles exosomes biomimetic nanovesicles acoustics disease diagnostics therapeutics

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An adaptive machine learning-based optimization method in the aerodynamic analysis of a finite wing under various cruise conditions

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Theoretical & Applied Mechanics Letters 2024年第1期14卷 27-34页

作者： Zilan Zhang Yu ao Shaofan Li Grace X.Gu Department of Mechanical Engineering University of CaliforniaBerkeley 94720USA Department of Engineering Peking UniversityBeijing 100871China Department of Civil and Environmental Engineering University of CaliforniaBerkeley 94720USA

Conventional wing aerodynamic optimization processes can be time-consuming and imprecise due to the complexity of versatile flight *** of existing literature has considered two-dimensional infinite airfoil optimization,while three-dimensional finite wing optimizations are subject to limited study because of high computational *** we create an adaptive optimization methodology built upon digitized wing shape deformation and deep learning algorithms,which enable the rapid formulation of finite wing designs for specific aerodynamic performance demands under different cruise *** methodology unfolds in three stages:radial basis function interpolated wing generation,collection of inputs from computational fluid dynamics simulations,and deep neural network that constructs the surrogate model for the optimal wing *** has been demonstrated that the proposed methodology can significantly reduce the computational cost of numerical *** also has the potential to optimize various aerial vehicles undergoing different mission environments,loading conditions,and safety requirements.

关键词： Aerodynamic optimization Computational fluid dynamics Radial basis function Finite wing Deep learning neural network

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Automated identification of steel weld defects,a convolutional neural network improved machine learning approach

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Frontiers of Structural and Civil Engineering 2024年第2期18卷 294-308页

作者： Zhan SHU ao WU Yuning SI Hanlin DONG Dejiang WANG Yifan LI School of Mechanics and Engineering Science Shanghai UniversityShanghai 200444China School of Civil Engineering Shanghai Normal UniversityShanghai 201418China Shanghai PinlanData Technology Co. Ltd.Shanghai 200072China

This paper proposes a machine-learning-based methodology to automatically classify different types of steel weld defects,including lack of the fusion,porosity,slag inclusion,and the qualified(no defects)*** methodology solves the shortcomings of existing detection methods,such as expensive equipment,complicated operation and inability to detect internal *** study first collected percussed data from welded steel members with or without weld ***,three methods,the Mel frequency cepstral coefficients,short-time Fourier transform(STFT),and continuous wavelet transform were implemented and compared to explore the most appropriate features for classification of weld *** and convolutional neural network-enhanced algorithms were used to classify,the extracted ***,experiments were designed and performed to validate the proposed *** showed that STFT achieved higher accuracies(up to 96.63%on average)in the weld status *** convolutional neural network-enhanced support vector machine(SVM)outperformed six other algorithms with an average accuracy of 95.8%.In addition,random forest and SVM were efficient approaches with a balanced trade-off between the accuracies and the computational efforts.

关键词： steel weld machine learning convolutional neural network weld defect detection classification task percussion

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利用十字交叉法测试织物弯曲悬垂性

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纺织学报 2018年第6期39卷 42-46页

作者：刘成霞周澳浙江理工大学服装学院浙江杭州310018 服装数字化技术浙江省工程实验室浙江杭州310018

为探索可同时测试织物弯曲性和悬垂性的方法,以20块常见织物为研究对象,分别用斜面法和圆台法测试弯曲长度和悬垂系数,然后用自行设计的十字交叉法进行测试,并提取了横向下垂距离、纵向下垂距离和弯曲悬垂系数。研究结果表明:十字交叉... 详细信息

为探索可同时测试织物弯曲性和悬垂性的方法,以20块常见织物为研究对象,分别用斜面法和圆台法测试弯曲长度和悬垂系数,然后用自行设计的十字交叉法进行测试,并提取了横向下垂距离、纵向下垂距离和弯曲悬垂系数。研究结果表明:十字交叉法既可用来检测织物弯曲性,也可检测织物悬垂性,且3个指标与斜面法的弯曲长度都具有较好的相关性,其相关系数由大到小依次是弯曲悬垂系数、横向下垂距离、纵向下垂距离;弯曲悬垂系数与圆台法测得的悬垂系数也具有高度相关性;十字交叉法将传统的织物弯曲性和悬垂性的测试合二为一,既简化了操作步骤,又节约了时间。

关键词：织物弯曲性悬垂性弯曲悬垂系数弯曲长度

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TEM and TEM-EDX Analysis of Cross-section of TiO_2Thin Film and Glass Substrate

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International Journal of Minerals,Metallurgy and Materials 1997年第2期11卷 55-56页

作者： YU Xingang MA Hongwen LUO Wuwen zhou ao KOU Qinghua ZHao Huifeng (Department of Materials Science, CUG, Beijing, 100083, China) (Research Institute of Glass, CBMA)

TiO2 thin film was deposited on Na-Ca-Si glass substrate by sol-gel process. TEM observation showed that the film is compactly joined to the substrate. TEM-EDX analyses of the film, film-substrate interface, and subst... 详细信息

关键词： thin film sol-gel titania diffusion

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Rare earth element-modified MOF materials:synthesis and photocatalytic applications in environmental remediation

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Rare Metals 2024年第4期43卷 1390-1406页

作者： Shu-Kun Le Qi-Jie Jin Jia-ao Han Hua-Cong zhou Quan-Sheng Liu Fu Yang Jie Miao Pei-Pei Liu Cheng-Zhang Zhu Hai-Tao Xu Inner Mongolia Key Laboratory of High-Value Functional Utilization of Low Rank Carbon Resources Chemical Engineering CollegeInner Mongolia University of TechnologyHohhot010050China School of Environmental Science and Engineering Nanjing Tech UniversityNanjing210009China School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang212100China Institut National de la Recherche Scientifique-Énergie Matériaux et Télécommunications MontrealQCJ3X 1P7Canada

Metal-organic framework-like materials(MOFs)have been developed in the fields of photocatalysis for their excellent optical properties and physicochemical properties,including environmental remediation,CO_(2)photoreduction,water splitting,and so *** their important roles in various fields,rare earth elements have received growing interests from *** MOFs with rare earth elements for modification allows broadening the absorption spectrum,while the active electrons on their empty 4f orbitals can act as traps to capture photoexcited carriers to inhibit the recombination of electron-hole pairs,thus promoting photocatalytic ***,rare earth elements modified MOFs provide an attractive way to achieve their high value *** this mini-review,the synthesis of rare earth element-modified MOFs photocatalysts and corresponding applications in the removal of antibiotics,CO_(2)reduction,and hydrogen production are constructively summarized and ***,the latest advancements and current difficulties of these materials as well as the application prospects are also provided.

关键词： Rare earth metals MOFs Photocatalytic CO_(2) reduction Environmental remediation Water splitting

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Reliability analysis of carbon fiber rod-reinforced umbilical cable under tension using an improved sampling method

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Petroleum Science 2024年第4期21卷 2769-2778页

作者： Yu Zhang Hong-Yu Zhang Ran Xia Si-ao Jiang Fang Wang College of Safety and Ocean Engineering China University of Petroleum China Academy of Aerospace Aerodynamics China Aerospace Science and Technology Group College of Engineering Science and Technology Shanghai Ocean University

The umbilical cable is a vital component of subsea production systems that provide power, chemical agents, control signals et al., and its requirement for reliability is exceedingly high. However, as the umbilical cable is a composite structure comprising multiple functional units, the reliability analysis of such cables involves numerous parameters that can impact calculation efficiency. In this paper, the reliability analysis of a new kind of umbilical cable with carbon fiber rod under tension is analyzed. The global dynamic analytical model is first established to determine the maximum tension load, then the local analytical model of umbilical cable including each unit are constructed by finite element method(FEM). Based on the mechanical analytical model, the reliability of umbilical cable under tension load is studied using response surface method(RSM) and Monte Carlo method. During the calculation process, a new tangent plane sampling method to calculate the response surface function(RSF) is proposed in this paper, which could make sampling points faster come close to the RSF curve, and it is proved that the calculation efficiency increases about 33% comparing with traditional method.

关键词： Umbilical cable Carbon fiber rod Failure analysis Response surface method Reliability

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QoS Routing Optimization Based on Deep Reinforcement Learning in SDN

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Computers, Materials & Continua 2024年第5期79卷 3007-3021页

作者： Yu Song Xusheng Qian Nan Zhang Wei Wang ao Xiong State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing100876China Marketing Service Center State Grid Jiangsu Electric Power Co.Ltd.Nanjing220000China Customer Service Center State Grid Co.Ltd.Nanjing211161China

To enhance the efficiency and expediency of issuing e-licenses within the power sector, we must confront thechallenge of managing the surging demand for data traffic. Within this realm, the network imposes stringentQuality of Service (QoS) requirements, revealing the inadequacies of traditional routing allocation mechanismsin accommodating such extensive data flows. In response to the imperative of handling a substantial influx of datarequests promptly and alleviating the constraints of existing technologies and network congestion, we present anarchitecture forQoS routing optimizationwith in SoftwareDefinedNetwork (SDN), leveraging deep reinforcementlearning. This innovative approach entails the separation of SDN control and transmission functionalities, centralizingcontrol over data forwardingwhile integrating deep reinforcement learning for informed routing decisions. Byfactoring in considerations such as delay, bandwidth, jitter rate, and packet loss rate, we design a reward function toguide theDeepDeterministic PolicyGradient (DDPG) algorithmin learning the optimal routing strategy to furnishsuperior QoS provision. In our empirical investigations, we juxtapose the performance of Deep ReinforcementLearning (DRL) against that of Shortest Path (SP) algorithms in terms of data packet transmission delay. Theexperimental simulation results show that our proposed algorithm has significant efficacy in reducing networkdelay and improving the overall transmission efficiency, which is superior to the traditional methods.

关键词： Deep reinforcement learning SDN route optimization QoS

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