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Coordination Mechanism and Empirical Research on Marine Science Technology Innovation and Marine Eco-civilization:A Case Study of Coastal Areas of China

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Chinese Geographical Science 2024年第3期34卷 468-486页

作者： chen Xiaolong LIANG chenlu di Qianbin School of Geographical Science Liaoning Normal UniversityDalian 116029China Institute of Marine Sustainable Development Liaoning Normal UniversityDalian 116029China

Marine science technology innovation provides power and guarantees for marine eco-civilization construction,which provides direction and material support for marine science technology ***,the coordinated development of the two is of great significance to the marine economy sustainable development in China’s coastal *** the basis of clarifying the connotations of marine science technology innovation and marine eco-civilization in China’s coastal areas from 2006 to 2019,the mechanism for their coordinated development was analysed.A comprehensive indicator system based on the connotation of the two was constructed,and the coordinated development relationship was empirically tested using the coupled coordination model and the panel vector autoregressive(PVAR)*** results show that:1)the level of China’s coastal marine science technology innovation continues to improve,gradually forming the core of the development of marine science technology innovation in the north,east and south of Shandong,Shanghai and Guangdong;the level of marine eco-civilization development fluctuating upward trend,showing obvious spatial differentiation characteristics.2)The degree of coordination of marine science technology innovation and marine eco-civilization is growing over *** is no causal relationship between marine science technology innovation and marine eco-civilization in the northern marine economic circle,but there is a two-way causal relationship between the two in the eastern and southern marine economic circles.3)Marine eco-civilization shows a significant positive and continuous impact on marine science technology innovation,and marine science technology innovation shows a long-term,continuous,fluctuating,and lagging impact on marine *** overall role of marine eco-civilization on marine science technology innovation is dominant,and there are significant differences in the impact effects of the two major marine economic circles.

关键词： marine science technology innovation marine eco-civilization coordinated development coastal areas of China

Mechanical Performance of Bio-inspired Bidirectional Corrugated Sandwich Pressure Shell Under External Hydrostatic Pressure

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China Ocean Engineering 2024年第2期38卷 297-312页

作者： ZHANG Yi chen Yue yun Lai LIANG Xu Ocean College Zhejiang UniversityZhoushan 316000China Hainan Institute Zhejiang UniversitySanya 572000China

This paper aims to enhance the compression capacity of underwater cylindrical shells by adopting the corrugated sandwich structure of *** cuttlebone suffers uniaxial external compression,while underwater cylindrical shells are in a biaxial compressive stress *** suit the biaxial compressive stress state,a novel bidirectional corrugated sandwich structure is proposed to improve the bearing capacity of cylindrical *** static and buckling analysis for the sandwich shell and the unstiffened cylindrical shell with the same volume-weight ratio are studied by numerical *** is indicated that the proposed sandwich shell can effectively reduce the ratio between circumferential and axial stress from 2 to 1.25 and improve the critical buckling load by about 1.63 *** simulation shows that optimizing and adjusting the structural parameters could significantly improve the advantage of the sandwich ***,the hydrostatic pressure tests for shell models fabricated by 3D printing are carried *** to the experimental results,the overall failure position of the sandwich shell is at the center part of the sandwich *** has been found the average critical load of the proposed sandwich shell models exceeds two times that of the unstiffened shell ***,the proposed bio-inspired bidirectional corrugated sandwich structure can significantly enhance the pressure resistance capability of cylindrical shells.

关键词： bio-inspiration bidirectional corrugation sandwich shell external pressure buckling

Degradation-adaptive neural network for jointly single image dehazing and desnowing

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Frontiers of Computer Science 2024年第2期18卷 247-249页

作者： Erkang chen Sixiang chen Tian YE yun LIU School of Ocean Information Engineering Jimei UniversityXiamen 361021 China College of Artificial Intelligence Southwest UniversityChongqing 400715 China

1 Introduction In harsh winter scenes,the captured images often suffer from hazeand snowdegradationssimultaneously,which significantly affect the performance of high-level computer vision ***,most existing dehazing methods[1-4]and desnowing methods[5-7]are specialized to address only one type of weather-related degradation,and they struggle to effectively handle multiple types of degradations.

关键词： neural handle computer

The synthetic gauge field and exotic vortex phase with spin-orbital-angular-momentum coupling

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Communications in Theoretical Physics 2024年第8期76卷 52-59页

作者： Yingqi Liu yun chen Yuangang Deng Guangdong Provincial Key Laboratory of Quantum Metrology and Sensing&School of Physics and Astronomy Sun Yat-Sen University(Zhuhai Campus)Zhuhai 519082China

Ultracold atoms endowed with tunable spin-orbital-angular-momentum coupling(SOAMC)represent a promising avenue for delving into exotic quantum phenomena. Building on recent experimental advancements, we propose the generation of synthetic gauge fields, and by including exotic vortex phases within spinor Bose-Einstein condensates, employing a combination of a running wave and Laguerre-Gaussian laser fields. We investigate the ground-state characteristics of the SOAMC condensate, revealing the emergence of exotic vortex states with controllable orbital angular momenta. It is shown that the interplay of the SOAMC and conventional spin-linear-momentum coupling induced by the running wave beam leads to the formation of a vortex state exhibiting a phase stripe hosting single multiply quantized singularity. The phase of the ground state will undergo the phase transition corresponding to the breaking of rotational symmetry while preserving the mirror symmetry. Importantly, the observed density distribution of the ground-state wavefunction, exhibiting broken rotational symmetry, can be well characterized by the synthetic magnetic field generated through light interaction with the dressed spin state. Our findings pave the way for further exploration into the rotational properties of stable exotic vortices with higher orbital angular momenta against splitting in the presence of synthetic gauge fields in ultracold quantum gases.

关键词： ultracold atoms synthetic gauge fields vortex phases spin-orbital-angularmomentum coupling

High Seebeck Coefficient Thermally Chargeable Supercapacitor with Synergistic Effect of Multichannel Ionogel Electrolyte and Ti_(3)C_(2)T_(x)MXene-Based Composite Electrode

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Energy & Environmental Materials 2024年第6期7卷 367-377页

作者： Zhongming chen Zhijian Du La Li Kai Jiang di chen Guozhen Shen School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081China Faculty of Hepato-Pancreato-Biliary Surgery Chinese PLA General HospitalInstitute of Hepatobiliary Surgery of Chinese PLA&Key Laboratory of Digital Hepetobiliary SurgeryChinese PLABeijing 100853China

Thermally chargeable supercapacitors can collect low-grade heat generated by the human body and convert it into electricity as a power supply unit for wearable ***,the low Seebeck coefficient and heat-to-electricity conversion efficiency hinder further *** this paper,we designed a high-performance thermally chargeable supercapacitor device composed of ZnMn_(2)O_(4)@Ti_(3)C_(2)T_(x)MXene composites(ZMO@Ti_(3)C_(2)T_(x)MXene)electrode and UIO-66 metal–organic framework doped multichannel polyvinylidene fluoridehexafluoro-propylene ionogel electrolyte,which realized the thermoelectric conversion and electrical energy storage at the same *** thermally chargeable supercapacitor device exhibited a high Seebeck coefficient of 55.4 mV K^(−1),thermal voltage of 243 mV,and outstanding heat-to-electricity conversion efficiency of up to 6.48%at the temperature difference of 4.4 *** addition,this device showed excellent charge–discharge cycling stability at high-temperature differences(3 K)and low-temperature differences(1 K),*** two thermally chargeable supercapacitor units in series,the generated output voltage of 500 mV further confirmed the stability of *** a single device was worn on the arm,a thermal voltage of 208.3 mV was obtained indicating the possibility of application in wearable electronics.

关键词： ionogel electrode Soret effect thermally chargeable supercapacitor Ti_(3)C_(2)T_(x)MXene UIO-66 MOF

Structural characteristics and drivers of greenhouse gas emissions at county-level and long-time scales:A case study of the Anji County,China

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Journal of Environmental Sciences 2024年第6期140卷 319-330页

作者： Zhouxiang Cai Liting Hu di chen Ying Zhang Xuekun Fang College of Environmental&Resource Sciences Zhejiang UniversityHangzhou 310058China Center for Global Change Science Massachusetts Institute of TechnologyCambridgeMA 02139United States Anji Meteorological Bureau Anji 313300China

To achieve carbon neutrality,the Chinese government needs to gain a comprehensive understanding of the sources and drivers of greenhouse gas(GHG)emissions,particularly at the county *** County in eastern China is a typical example of an industrial transformation from quarrying to a low-carbon *** study analyzed the decoupling types and structural characteristics of GHG emissions and the driving factors of carbon dioxide(CO_(2))emissions in the Anji from 2006 to 2019,and explored the differences between countylevel and provincial-level or city-level *** was observed that energy-related activities are the main source of GHG emissions in Anji and that economic development is the driving factor behind the increasing CO_(2)***,industrial transformation and upgradation coupled with the alternative use of clean energy limit the growth of GHG *** study details the GHG emissions of county during the industrial transformation stage and provides corresponding policy recommendations for county governments.

关键词： County GHG emissions Decoupling Driving factors Policy recommendations

Optical Extinctions of Inter-Arm Molecular Clouds in M31:A Pilot Study for the Upcoming CSST Observations

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Research in Astronomy and Astrophysics 2024年第6期24卷 323-333页

作者： Cailing chen Zheng Zheng Chao-Wei Tsai Sihan Jiao Jing Tang Jingwen Wu di Li yun Zheng Linjing Feng Yujiao Yang Yuan Liang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Radio Astronomy and Technology Chinese Academy of SciencesBeijing 100101China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Zhejiang Lab Hangzhou 311121China

Recent submillimeter dust thermal emission observations have unveiled a significant number of inter-arm massive molecular clouds in ***,the effectiveness of this technique is limited to its sensitivity,making it challenging to study more distant *** study introduces an alternative approach,utilizing optical extinctions derived from space-based telescopes,with a focus on the forthcoming China Space Station Telescope(CSST).We first demonstrate the capability of this method by constructing dust extinction maps for 17 inter-arm massive molecular clouds in M31 using the Panchromatic Hubble Andromeda Treasury *** analysis reveals that inter-arm massive molecular clouds with an optical extinction(A_(V)) greater than 1.6 mag exhibit a notable A_(V) excess,facilitating their *** majority of these inter-arm massive molecular clouds show an A_(V) around 1 mag,aligning with measurements from our JCMT *** validation using a mock CSST RGB star catalog confirms the method's *** show that the derived A_(V)values using CSST z and y photometries align more closely with the input *** clouds with A_(V)> 1.6 mag can also be identified using the CSST mock *** thus claim that future CSST observation clouds provide an effective way for the detection of inter-arm massive molecular clouds with significant optical extinction in nearby galaxies.

关键词： infrared:stars ISM:clouds Galaxy:structure

Precise determination of the pole position of the exotic Z_(c)(3900)

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 84-90页

作者： yun-Hua chen Meng-Lin Du Feng-Kun Guo School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China School of Physics University of Electronic Science and Technology of ChinaChengdu 611731China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China

We perform a unified description of the experimental data of the π^(+)π^(-)and J/ψπ^(±)invariant mass spectra for e^(+)e^(-)→J/ψπ^(+)π^(-)and the D^(0)D^(*-)mass spectrum for e^(+)e^(-)→D^(0)D^(*-)π^(+)at e^(+)e^(-)center-of-mass energies 4.23 and 4.26 *** analysis takes into account open-charm meson loops that contain triangle singularities,the J/ψπ-DD^(*)coupled-channel interaction respecting unitarity,and the strong ππ-KK final state interaction using dispersion *** analysis leads to a precise determination of the Z_(c)(3900)pole with the pole mass and width(3880.7±1.7_(stat)±22.4_(syst))MeV and(35.9±1.4_(stat)±15.3_(syst))MeV,respectively,and hints at that the DD^(*)molecular and non-molecular components are of similar importance in the Z_(c)(3900)formation.

关键词： exotic hadrons dispersion relations final state interaction triangle singularity

Numerical Investigation of the Angle of Attack Effect on Cloud Cavitation Flow around a Clark-Y Hydrofoil

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2947-2964页

作者： di Peng Guoqing chen Jiale Yan Shiping Wang College of Engineering Peking UniversityBeijing100871China College of Shipbuilding Engineering Harbin Engineering UniversityHarbin150001China

Cavitation is a prevalent phenomenon within the domain of ship and ocean engineering,predominantly occurring in the tail flow fields of high-speed rotating propellers and on the surfaces of high-speed underwater *** re-entrant jet and compression wave resulting from the collapse of cavity vapour are pivotal factors contributing to cavity ***,these phenomena significantly modulate the evolution of cavitation *** this paper,numerical investigations into cloud cavitation over a Clark-Y hydrofoil were conducted,utilizing the Large Eddy Simulation(LES)turbulence model and the Volume of Fluid(VOF)method within the OpenFOAM *** analysis of results obtained at different angles of attack is undertaken.A discernible augmentation in cavity thickness is observed concomitant with the escalation in attack angle,alongside a progressive intensification in pressure at the leading edge of the hydrofoil,contributing to the suction *** results can serve as a fundamental point of reference for gaining a deeper comprehension of cloud cavitation dynamics.

关键词： Cloud cavitation re-entrant jet compression wave clark-Y hydrofoil