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Research on the generation method of seawater sound velocity model based on Perlin noise

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Acta Oceanologica Sinica 2024年第1期43卷 99-111页

作者： Zhimiao Chang Fuxing han Zhangqing sun Zhenghui Gao Xueqiu Wang College of Geoexploration Science and Technology Jilin UniversityChangchun 130026China

In the processing of conventional marine seismic data,seawater is often assumed to have a constant velocity ***,due to static pressure,temperature difference and other factors,random disturbances may often frequently in seawater *** impact of such disturbances on data processing results is a topic of theoretical *** seawater sound velocity is a difficult physical quantity to measure,there is a need for a method that can generate models conforming to seawater *** article will combine the Munk model and Perlin noise to propose a two-dimensional dynamic seawater sound velocity model generation method,a method that can generate a dynamic,continuous,random seawater sound velocity model with some regularity at large ***,the paper discusses the influence of the inhomogeneity characteristics of seawater on wave field propagation and *** results show that the seawater sound velocity model with random disturbance will have a significant influence on the wave field simulation and imaging results.

关键词： Munk model Perlin noise seawater inhomogeneity

Real-time pore structure evolution difference between deep and shallow coal during gas adsorption:A study based on synchrotron radiation small-angle X-ray scattering

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Particuology 2024年第4期87卷 114-123页

作者： Yingfeng sun Shuaipeng Zhu Fei Xie Chujian han Yixin Zhao Zetian Zhang Research Institute of Macro-Safety Science University of Science and Technology BeijingBeijing100083China Schoolof Civiland Resource Engineering University of Science and Technology BeijingBeijing100083China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei230029China Beijing Key Laboratory for Precise Mining of Intergrown Energy and Resources China University of Mining and Technology(Beijing)Bejing10003 China School of Energy and Mining Engineering China University of Mining and Technology(Beijing)Beijing100083China Key Laboratory of Deep Earth Science and Engineering(Sichuan University) Ministry of EducationChengdu610065China

Coal seam CO_(2) sequestration is an important option to address global warming.A better knowledge on coal pore structure evolution during gas adsorption can provide guidance for coal seams CO_(2) ***,few investigations on the pore structure evolution differences between the deep and shallow coal were conducted during gas *** this study,based on the real-time synchrotron radiation small-angle X-ray scattering(SAXS)observation,the average pore diameter and pore surface fractal dimension evolution differences between deep and shallow coal were investigated from the as-pects of coal compositions and stress *** types of coal deformation(inner-swelling and outer-swelling)coexist during gas *** compositions have significant impact on the dominance of deformation *** dominance of inner-swelling in deep coal is induced by the higher ash contents,and there is the decrease of average pore diameter during gas *** impact of stress-history(burial depth)on adsorption-induced deformation is more prominent than that of gas adsorption *** deep coal,the surface fractal dimension evolution presents a negative correlation with the evolution of pore *** shallow coal,the surface fractal dimension evolution presents a Langmuir-type correlation with the adsorption time.

关键词： Coal Gas adsorption Synchrotron radiation small-angle X-ray scattering Pore diameter Surface fractal dimension

Recent process developments in beneficiation and metallurgy of rare earths:A review

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Journal of Rare Earths 2024年第4期42卷 629-642页

作者： Shaokai Cheng Wenbo Li Yuexin han Yongsheng sun Peng Gao Xiaolong Zhang School of Resources and Civil Engineering Northeastern UniversityShenyang110819China National-local Joint Engineering Research Center of High-efficient Exploitation Technology for Refractory Iron Ore Resources Shenyang110819China

Rare earth elements(REEs)are irreplaceable materials supporting low-carbon technology and equip-ment,and their commercial demand and strategic position are becoming increasingly *** the continuous depletion of rare earth(RE)resources,developing high-efficiency beneficiation and eco-friendly metallurgical processes has attracted widespread *** paper reviews the major minerals exploited for RE production and their deposits,as well as the beneficiation and metallurgical processes of RE ***,monazite,mixed RE ores,and ion-adsorption clays are the main raw materials in the world to ***-bearing ores(except ion-adsorption minerals)are generally beneficiated by flotation,gravity and magnetic separation *** mainstream metallurgical processes for bastnaesite,monazite and mixed RE concentrates are oxidation roasting-HCl leaching,caustic soda decomposition and high-temperature concentrated sulfuric acid roasting,***-adsorption clays are directly processed by in situ leaching-precipitation/solvent *** achieve the sustainable development of RE resources,it is essential to further explore innovative techniques to achievecomprehensive utilization and cleaner production.

关键词： Rare earths Beneficiation processes Metallurgical processes Cleaner production

The First Ground-based White Light Lunar Polarization Imaging:A New Kind of FeO Observation on the Near Side of the Moon

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Research in Astronomy and Astrophysics 2024年第6期24卷 1-6页

作者： wei-Nan Wang Jin-Song Ping Ming-Yuan Wang Wen-Zhao Zhang han-Lin Ye Xing-wei han Song-Feng Kou Changchun Observatory National Astronomical ObservatoriesChinese Academy of SciencesChangchun 130117China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 101408China Astronomy Department Beijing Normal UniversityBeijing 100875China International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Nanjing Institute of Astronomical Optics and Technology Chinese Academy of SciencesNanjing 210042China

Lunar optical polarization is a fascinating phenomenon that occurs when sunlight reflects off the surface of the Moon and becomes *** study employs a novel split-focus plane polarimetric camera to conduct the initial white light polarimetric observations on the near side of the *** obtained the linear degree of polarization(DOP)parameters of white light by observation from the eastern and western hemispheres of the *** findings indicate that the white light polarization is lower in the lunar highland than in the lunar maria *** the analysis of lunar soil samples,we noticed and determined that the DOP parameters of white light demonstrate high consistency with iron oxide on the *** study may serve as a new diagnostic tool for the Moon.

关键词： techniques:photometric polarization methods:observational Moon

Structural Characteristics and Influencing Factors of Carbon Emission Spatial Association Network:A Case Study of Yangtze River Delta City Cluster,China

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Chinese Geographical Science 2024年第4期34卷 689-705页

作者： BI Xi sun Renjin HU Dongou SHI Hongling ZhanG han School of Economics and Management China University of Petroleum(Beijing)Beijing 102249China China Petroleum Planning&Engineering Institute Beijing 100083China

City cluster is an effective platform for encouraging regionally coordinated *** reduction of carbon emissions within city cluster via the spatial association network between cities can help coordinate the regional carbon emission management,realize sustainable development,and assist China in achieving the carbon peaking and carbon neutrality *** paper applies the improved gravity model and social network analysis(SNA)to the study of spatial correlation of carbon emissions in city clusters and analyzes the structural characteristics of the spatial correlation network of carbon emissions in the Yangtze River Delta(YRD)city cluster in China and its influencing *** results demonstrate that:1)the spatial association of carbon emissions in the YRD city cluster exhibits a typical and complex multi-threaded network *** network association number and density show an upward trend,indicating closer spatial association between cities,but their values remain generally ***,the network hierarchy and network efficiency show a downward trend but remain high.2)The spatial association network of carbon emissions in the YRD city cluster shows an obvious‘core-edge’distribution *** network is centered around Shanghai,Suzhou and Wuxi,all of which play the role of‘bridges’,while cities such as Zhoushan,Ma'anshan,Tongling and other cities characterized by the remote location,single transportation mode or lower economic level are positioned at the edge of the network.3)Geographic proximity,varying levels of economic development,different industrial structures,degrees of urbanization,levels of technological innovation,energy intensities and environmental regulation are important influencing factors on the spatial association of within the YRD city ***,policy implications are provided from four aspects:government macro-control and market mechanism guidance,structural characteristics of the‘core-edge’network,reconfigura

关键词： carbon emission spatial association network social network analysis(SNA) quadratic assignment procedure(QAP)model Yangtze River Delta city cluster China

A wideband,high-resolution vector spectrum analyzer for integrated photonics

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Light(Science & Applications) 2024年第4期13卷 760-771页

作者： Yi-han Luo Baoqi Shi wei sun Ruiyang Chen Sanli Huang Zhongkai Wang Jinbao Long Chen Shen Zhichao Ye Hairun Guo Junqiu Liu International Quantum Academy 518048 ShenzhenChina. Shenzhen Institute for Quantum Science and Engineering Southern University of Science and Technology518055 ShenzhenChina. Department of Optics and Optical Engineering University of Science and Technology of China230026 HefeiChina. Hefei National Laboratory University of Science and Technology of China230088 HefeiChina. Qaleido Photonics 518048 ShenzhenChina. Key Laboratory of Specialty Fiber Optics and Optical Access Networks Shanghai University200444 ShanghaiChina

The analysis of optical spectra—emission or absorption—has been arguably the most powerful approach for discovering and understanding *** invention and development of many kinds of spectrometers have equipped us with versatile yet ultra-sensitive diagnostic tools for trace gas detection,isotope analysis,and resolving hyperfine structures of atoms and *** proliferating data and information,urgent and demanding requirements have been placed today on spectrum analysis with ever-increasing spectral bandwidth and frequency *** requirements are especially stringent for broadband laser sources that carry massive information and for dispersive devices used in information processing *** addition,spectrum analyzers are expected to probe the device’s phase response where extra information is *** we demonstrate a novel vector spectrum analyzer(VSA)that is capable of characterizing passive devices and active laser sources in one *** a dual-mode VSA can measure loss,phase response,and dispersion properties of passive *** also can coherently map a broadband laser spectrum into the RF *** VSA features a bandwidth of 55.1 THz(1260–1640 nm),a frequency resolution of 471 kHz,and a dynamic range of 56 ***,our fiber-based VSA is compact and *** requires neither high-speed modulators and photodetectors nor any active feedback ***,we employ our VSA for applications including characterization of integrated dispersive waveguides,mapping frequency comb spectra,and coherent light detection and ranging(LiDAR).Our VSA presents an innovative approach for device analysis and laser spectroscopy,and can play a critical role in future photonic systems and applications for sensing,communication,imaging,and quantum information processing.

关键词： spectrum resolution coherent

The Influence of Different Solar System Planetary Ephemerides on Pulsar Timing

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Research in Astronomy and Astrophysics 2024年第8期24卷 87-101页

作者： Jian-Peng Dai wei han Na Wang School of Physical Science and Technology Xinjiang University Xinjiang Astronomical Observatory Chinese Academy of Sciences University of Chinese Academy of Sciences Xinjiang Key Laboratory of Radio Astrophysics

Pulsar timing offers a comprehensive avenue for exploring diverse topics in physics and *** solar system planetary ephemeris is crucial for pulsar timing as it provides the positions and velocities of solar system planets including the ***,it is inevitable that inherent inconsistencies exist in these *** between various ephemerides can significantly impact pulsar timing and parameter ***,pulsar timing highly depends on the JPL DE ephemeris,for instance,the Pulsar Timing Array data analysis predominantly utilizes *** this study,we examine inconsistencies across various ephemeris series,including JPL DE,EPM,and ***,discrepancies emerge particularly between the current ephemeris DE436 and the earliest released ephemeris DE200,as well as the most recent ephemerides,e.g.,DE440,INPOP21A,and *** detailed analysis of the effects of ephemeris on geometric correction procedures for the conversion of measured topocentric times of arrival is presented in this *** researches reveal that variations in the Roemer delays across different ephemerides lead to distinct *** timing residuals and the fact that these discrepancies can be readily incorporated into the subsequent pulsar parameters,leading to inconsistent fitting estimates,suggest that the influence of errors in the ephemeris on the timing process might currently be underappreciated.

关键词： (stars:) pulsars: general ephemerides Planetary Systems time

Emotional differences based on comments on doctor-patient disputes with varying levels of severity

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World Journal of Psychiatry 2024年第7期14卷 1068-1079页

作者： Jing-Ru Lu Yu-han wei Xin Wang Yu-Qing Zhang Jia-Yi Shao Jiang-Jie sun School of Health Care Management Anhui Medical UniversityHefei 230032Anhui ProvinceChina School of Management Hefei University of TechnologyHefei 230039Anhui ProvinceChina

BACKGROUND The risks associated with negative doctor-patient relationships have seriously hindered the healthy development of medical and healthcare and aroused wide-spread concern in *** number of public comments on doctor-patient relationship risk events reflects the degree to which the public pays attention to such *** incidents of doctor-patient disputes were collected from weibo and TikTok,and 3655 related comments were *** number of comment sentiment words was extracted,and the comment sentiment value was *** Kruskal-Wallis H test was used to compare differences between each variable group at different levels of ***’s correlation analysis was used to examine associations between *** analysis was used to explore factors influencing scores of comments on *** The study results showed that public comments on media reports of doctor-patient disputes at all levels are mainly dominated by“good”and“disgust”emotional *** was a significant difference in the comment scores and the number of partial emotion words between comments on varying levels of severity of doctor-patient *** comment score was positively correlated with the number of emotion words related to positive,good,and happy)and negatively correlated with the number of emotion words related to negative,anger,disgust,fear,and *** The number of emotion words related to negative,anger,disgust,fear,and sadness directly influences comment scores,and the severity of the incident level indirectly influences comment scores.

关键词： Doctor-patient relationship Doctor-patient dispute Comments Emotional differences weibo TikTok

Nonlinear Registration of Brain Magnetic Resonance Images with Cross Constraints of Intensity and Structure

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Computers, Materials & Continua 2024年第5期79卷 2295-2313页

作者： han Zhou HongtaoXu Xinyue Chang wei Zhang Heng Dong Digital Fujian Research Institute of Big Data forAgriculture and Forestry Fujian Agriculture and Forestry UniversityFuzhou350002China College of Computer and Information Science Fujian Agriculture and Forestry UniversityFuzhou350002China

Many deep learning-based registration methods rely on a single-stream encoder-decoder network for computing deformation fields between 3D ***,these methods often lack constraint information and overlook semantic consistency,limiting their *** address these issues,we present a novel approach for medical image registration called theDual-VoxelMorph,featuring a dual-channel cross-constraint *** innovative network utilizes both intensity and segmentation images,which share identical semantic information and feature *** encoder-decoder structures calculate deformation fields for intensity and segmentation images,as generated by the dual-channel cross-constraint *** design facilitates bidirectional communication between grayscale and segmentation information,enabling the model to better learn the corresponding grayscale and segmentation details of the same anatomical *** ensure semantic and directional consistency,we introduce constraints and apply the cosine similarity function to enhance semantic *** on four public datasets demonstrates superior performance compared to the baselinemethod,achieving Dice scores of 79.9%,64.5%,69.9%,and 63.5%for OASIS-1,OASIS-3,LPBA40,and ADNI,respectively.

关键词： Medical image registration cross constraint semantic consistency directional consistency dual-channel