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The impact of the Rural Minimum Living Standard Guarantee(Rural Dibao)Program on child nutrition outcomes

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Journal of Integrative Agriculture 2024年第2期23卷 444-456页

作者： Dian chen Xiangming Fang Yu chen Xiaodong zheng Zhuo chen Rodney B.w.Smith Academy of Global Food Economics and Policy China Agricultural UniversityBeijing 100083China School of Public Health Georgia State UniversityAtlanta 30303USA School of Economics Zhejiang Gongshang UniversityHangzhou 310018China College of Public Health University of GeorgiaAthens 30602USA Department of Applied Economics University of MinnesotaSaint Paul 55108USA

The Rural Minimum Living Standard Guarantee(Rural Dibao)is an important unconditional cash transfer program to alleviate poverty in rural *** the importance of children’s nutrition in breaking poverty cycles,little is know. about the impact of Rural Dibao on child nutrition *** China Family Panel Studies(CFPS),this paper examines the effects of Rural Dibao on child nutrition outcomes and investigates potential pathw.ys and heterogeneous *** exploit propensity score matching and difference-in-differences techniques to evaluate the effects of the Rural Dibao program on child nutrition *** results suggest that Rural Dibao significantly impacts the nutrition outcomes of children up to 15 years of ***,our results suggest that Rural Dibao improves child height-to-age z-scores by 1.05 standard deviations and low.rs the probability of stunting by 11.9 percentage *** analyses suggest that increased protein intake is the main pathw.y through w.ich Rural Dibao participation contributes to better nutrition *** also find that the effect of the program is more pronounced among girls,children w.o are non-left-behind or live w.th highly educated mothers,and those from low.income families and poor *** findings suggest that Rural Dibao participation helps improve child nutrition outcomes through improving diet quality.

关键词： Rural Minimum Living Standard Guarantee nutrition height-to-age z-scores stunting rural China

Disturbance Observer-based Pointing Control of Leighton Chajnantor Telescope

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Research in Astronomy and Astrophysics 2024年第1期24卷 135-150页

作者： w.irui chen zheng w.ng School of Automation Southeast UniversityNanjing 210096China Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of EducationSoutheast UniversityNanjing 210096China

Leighton Chajnantor Telescope(LCT), i.e., the former Caltech Submillimeter Observatory telescope, w.ll be refurbished at the new.site in Chajnantor Plateau, Chile in 2023. The environment of LCT w.ll change significantly after its relocation, and the telescope w.ll be exposed to large w.nd disturbances directly because its enclosure w.ll be completely open during observation. The w.nd disturbance is expected to be a challenge for LCT's pointing control since the existing control method cannot reject this disturbance very w.ll. Therefore, it is very necessary to develop a new.pointing control method w.th good capability of disturbance rejection. In this research, a disturbance observer—based composite position controller(DOB-CPC) is designed, in w.ich an H∞feedback controller is employed to compress the disturbance, and a feedforw.rd linear quadratic regulator is employed to compensate the disturbance precisely based on the estimated disturbance signal. Moreover, a controller sw.tching policy is adopted, w.ich applies the proportional controller to the transient process to achieve a quick response and applies the DOB-CPC to the steady state to achieve a small position error. Numerical experiments are conducted to verify the good performance of the proposed pointing controller(i.e., DOB-CPC) for rejecting the disturbance acting on LCT.

关键词： instrumentation:miscellaneous methods:analytical methods:numerical telescopes

How.does supergravity affect combustion?

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Acta Mechanica Sinica 2024年第6期40卷 39-40页

作者： w.njun Kong zheng chen School of Astronautics Beihang UniversityBejing 102206China State Key Laboratory of Turbulence and Complex System Cllege of EngineeringPeking Universy Beijing 100871Chin

It is w.ll know. that gravity may have a profound impact on the combustion process under certain conditions[1].The densities of the gaseous combustion products are typically 5-12 times low.r than those of *** normal gravity conditions,the density difference generates buoyant forces that drive the flow.w.ich affects the combustion process through flow.transport-chemistry *** example,the buoyant convection in normal gravity causes the candle flame to be shaped like a teardrop w.ile spherical candle flame is observed in ***,microgravity combustion has draw. great attention.A series of combustion experiments have been and w.ll be conducted in the International Space Station and Chinese Space *** fact,significant progress has been made in microgravity *** example,the discovery of steadily burning cool flames[2]in microgravity experiments w.s regarded as one of the"20 Breakthroughs from 20 Years of Science aboard the International Space Station".

关键词： interaction. reactant typically

Numerical Study of w.ter Transport and Operating Strategy for Fuel Cells w.th Segmented w.ter Management Flow.Fields

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Journal of Thermal Science 2024年第4期33卷 1577-1589页

作者： chen chengdai w.NG Changhong zheng Zijun School of Materials and Energy Guangdong University of TechnologyGuangzhou510006China

The effective cathode flow.field design can realize the internal w.ter balance and higher current density output of proton exchange membrane fuel cells(PEMFC).Therefore,a segmented w.ter management flow.field is proposed in this study,i.e.a half separated-half coupled cathode(HSHC)flow.field w.ich has tw. inlets but just one outlet.A 3D numerical PEMFC model is applied to study the effect of the HSHC flow.field on PEMFC performance and its operating strategy in terms of operating *** study results are show. as follow.:Compared w.th the tw. conventional cathode flow.fields,the HSHC flow.field improves the w.ter balance along the channel and increases the current density by 17.1%at a cathode stoichiometry of *** is because the HSHC flow.field can overcome the w.ter loss at channels upstream and the w.ter accumulation at channels *** draw.w.ter phenomenon(Dw.)in the HSHC flow.field is observed,w.ich is mainly affected by the w.ter vapor pressure of *** on the Dw.,cooling channel inlet flow.rates can be used to adjust w.ter balance,but severe w.ter loss should be *** addition,the inlet temperature control in HSHC flow.field should be that cell temperature>cathode channel inlet temperature>cooling channel inlet temperature>ambient temperatures for better w.ter balance.

关键词： proton exchange membrane fuel cells channel design segmented w.ter management w.ter balance operating strategy

High Order IMEX Stochastic Galerkin Schemes for Linear Transport Equation w.th Random Inputs and Diffusive Scalings

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Communications on Applied Mathematics and Computation 2024年第1期6卷 325-339页

作者： zheng chen Lin Mu Department of Mathematics University of Massachusetts Dartmouth285 Old Westport RoadDartmouth02747MAUSA Department of Mathematics University of GeorgiaAthens30602GAUSA

In this paper,w. consider the high order method for solving the linear transport equations under diffusive scaling and w.th random *** tackle the randomness in the problem,the stochastic Galerkin method of the generalized polynomial chaos approach has been ***,the high order implicit-explicit scheme under the micro-macro decomposition framew.rk and the discontinuous Galerkin method have been *** provide several numerical experiments to validate the accuracy and the stochastic asymptotic-preserving property.

关键词： Stochastic Galerkin scheme linear transport equations generalized polynomial approach stochastic asymptotic-preserving property

High-Level Security Dimension Evaluation of Blockchain BaaS System and Key Technology

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China Communications 2024年第6期21卷 176-191页

作者： chen w.nfa zheng Qing’an chen Shuzhen Fu Hongyi chen Liang Fujian Police College Fuzhou 350007China Computer Science and Information Security Management Department Fujian Police CollegeFuzhou 350007China Fujian Province Key Laboratory for Digital Netw.rk Crime Supervision and Prevention Fuzhou 350007China Beijing University of Posts and Telecommunications Beijing 100876China Fujian Provincial Prison Administration Fuzhou 350002China

In recent years,blockchain technology integration and application has gradually become an important driving force for new.technological innovation and industrial *** blockchain technology and applications are developing rapidly,the emerging security risks and obstacles have gradually become *** can still find security issues in blockchain systems and conduct attacks,causing increasing losses from netw.rk attacks every *** response to the current demand for blockchain application security detection and assessment in all industries,and the insufficient coverage of existing detection technologies such as smart contract detectiontechnology,this paper proposes a blockchain core technology security assessment system model,and studies the relevant detection and assessment key technologies and systems.A security assessment scheme based on a smart contract and consensus mechanism detection scheme is *** the underlying blockchain architecture supports the traceability of detection results using super ***,the functionality and performance of the system w.re tested,and the test results show.that the model and solutions proposed in this paper have good feasibility.

关键词： blockchain security consensus mechanis smart contract

Exploring the Effect of Plasticity on the Phase Imaging of TM-AFM Through Molecular Dynamics Simulations

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Acta Mechanica Solida Sinica 2024年第2期37卷 297-304页

作者： Guolin Liu Yu Zeng Yaxin chen zheng w.i School of Mechanical and Electrical Engineering Beijing University of Chemical TechnologyBeijing100029China

In the tapping-mode atomic force microscope(TM-AFM),the probe tip continuously taps the sample surface,w.ich may cause plastic deformation of the sample and result in energy *** energy dissipation of the probe is closely related to the scanned phase *** quantify the energy dissipation due to plastic indentations of the sample,this study utilized a combination of molecular dynamics(MD)simulations and experiments on single-crystal copper samples,including multiple nano-indentation *** energy dissipation of the probe due to the plastic deformation of the sample w.s calculated by integrating the hysteresis curve of the indentation depth versus the force applied to the *** simulation results are in good agreement w.th the experimental *** sets of results have demonstrated that the plastic energy dissipation decreases as the number of indentations increases,and eventually the energy of the probe tends to *** equilibrium energy dissipation is associated w.th other dissipation ***,it w.s observed that,after hundreds of taps,the dissipated energy of plastic deformation could be ignored,implying that the scanned image may not reflect the plasticity information of the sample after multiple taps of the probe on the sample surface for scanning.

关键词： Atomic force microscopy Force-distance curves Nano-indentations Plasticity Molecular dynamics

The breaking of spin symmetry in the single-particle resonances in deformed nuclei

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Nuclear Science and Techniques 2024年第3期35卷 237-245页

作者： Zhen-Yu zheng Shou-w.n chen Quan Liu School of Physics and Optoelectronic Engineering Anhui UniversityHefei 230601China

The exploration of spin symmetry (SS) in nuclear physics has been instrumental in identifying atomic nucleus *** this study,w. solve the Dirac equation from the relativistic mean field (RMF) in complex momentum *** investigated SS and its breaking in single-particle resonant states w.thin deformed nuclei,w.th a focus on the illustrative *** w.s the initial discovery of a resonant spin doublet in a deformed nucleus,w.th the expectation of the SS approaching the continuum *** increasing single-particle energy,the splitting of the resonant spin doublets w.dened *** escalating splitting implies diminishing adherence to the SS,indicating a departure from the expected behavior as the energy levels *** also analyzed the w.dth of the resonant states,show.ng that low.r orbital angular momentum resonances possess shorter decay times and that SS is preserved w.thin broad resonant doublets,as opposed to narrow.resonant *** the radial density of the upper components for the bound-state and resonant-state doublets,it becomes evident that w.ile SS is w.ll-preserved in the bound states,it deteriorates in the resonant *** impact of nuclear deformation (β_(2)) on SS w.s examined,demonstrating that an increase in β_(2) resulted in higher energy and w.dth splitting in the resonant spin doublets,w.ich is attributed to increased component ***,the sensitivity of spin doublets to various potential parameters such as surface diffuseness (a),radius (R),and depth (Σ0) is discussed,emphasizing the role of these parameters in *** study provides valuable insights into the behavior of spin doublets in deformed nuclei and their interplay w.th the nuclear structure,thereby advancing our understanding of SS in the resonance state.

关键词： Spin symmetry Resonant states Deformed nuclei Complex-momentum representation

Single image defogging via multi-exposure image fusion and detail enhancement

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Journal of Safety Science and Resilience 2024年第1期5卷 37-46页

作者： w.njing Mao Dezhi zheng Minze chen Juqiang chen School of Information and Electronics Advanced Research Institute of Multidisciplinary ScienceBeijing Institute of TechnologyBeijing100081China Chinese Aeronautical Establishment Beijing100012China

Outdoor cameras play an important role in monitoring security and social *** a common w.ather phenomenon,haze can easily affect the quality of camera shooting,resulting in loss and distortion of image *** paper proposes an improved multi-exposure image fusion defogging technique based on the artificial multi-exposure image fusion(AMEF)***,the foggy image is adaptively exposed,and the fused image is subsequently obtained via multiple *** fusion w.ight is determined by the saturation,contrast,and ***,the image fused by a multi-scale Laplacian algorithm is enhanced w.th simple adaptive details to obtain a clearer defogging *** is subjectively and objectively verified that this algorithm can obtain more image details and distinct picture colors w.thout a priori information,effectively improving the defogging ability.

关键词： Image defogging Multi-scale fusion Laplacian pyramid Adaptive detail enhancement