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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

过滤速度对DPF内颗粒沉积特性影响的试验研究

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内燃机工程 2014年第5期35卷 12-16,23页

作者：孟忠伟蒲云飞闫妍韩伟强西华大学交通与汽车工程学院汽车测控与安全四川省重点实验室成都610039

基于柴油机颗粒过滤器(DPF)沉积过程可视化台架,在不同过滤速度下研究颗粒物在DPF载体切片上的堆积密度、颗粒层渗透系数及孔隙率。研究结果表明:在自然堆积状态或过滤速度<0.15m/s时,碳黑的堆积密度分布在90kg/m3左右;当过滤速度<0.15... 详细信息

基于柴油机颗粒过滤器(DPF)沉积过程可视化台架,在不同过滤速度下研究颗粒物在DPF载体切片上的堆积密度、颗粒层渗透系数及孔隙率。研究结果表明:在自然堆积状态或过滤速度<0.15m/s时,碳黑的堆积密度分布在90kg/m3左右;当过滤速度<0.15m/s时,ZS1100与DK4A柴油机颗粒物的堆积密度大于碳黑堆积密度,分布在100kg/m3左右;随过滤速度的增大、颗粒粒径减小及SOF含量的增加,颗粒的堆积密度先快速增大,后逐渐趋于稳定值;随颗粒层厚度的增加,过滤压降呈现典型的三阶段变化;随过滤速度的增加,颗粒层渗透系数和孔隙率呈先快速降低,后逐渐趋于稳定值的趋势。

关键词：内燃机柴油机颗粒捕集器可视化堆积密度渗透系数孔隙率

Predictive value of bilirubin and serum γ-glutamyltranspeptidase levels in type-2 diabetes mellitus patients with acute coronary syndrome

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World Journal of Diabetes 2024年第1期15卷 34-42页

作者： Jie Chen Wan-Chao Zhang Xiao-qiang Tang Ruo-han Yin Tao Wang Xiao-Yu wei Chang-Jie Pan Radiology Department The Affiliated Changzhou No.2 People's Hospital of Nanjing Medical UniversityChangzhou 213164Jiangsu ProvinceChina Radiology Department The People’s Hospital of WuQia CountyWuqia 845450Xinjiang Uygur Autonomous RegionChina

BACKGROUND Cardiovascular disease is a major complication of diabetes mellitus(DM).Type-2 DM(T2DM)is associated with an increased risk of cardiovascular events and mortality,while serum biomarkers may facilitate the prediction of these *** differential diagnosis of T2DM complicated with acute coronary syndrome(ACS)plays an important role in controlling disease progression and improving *** To investigate the correlation of serum bilirubin andγ-glutamyltranspeptidase(γ-GGT)with major adverse cardiovascular events(MACEs)in T2DM patients with *** The clinical data of inpatients from January 2022 to December 2022 were analyzed *** to different conditions,they were divided into the T2DM complicated with ACS group(T2DM+ACS,n=96),simple T2DM group(T2DM,n=85),and simple ACS group(ACS,n=90).The clinical data and laboratory indices were compared among the three groups,and the correlations of serum total bilirubin(TBIL)levels and serumγ-GGT levels with other indices were discussed.T2DM+ACS patients received a 90-day follow-up after discharge and were divided into event(n=15)and nonevent(n=81)groups according to the occurrence of MACEs;Univariate and multivariate analyses were further used to screen the independent influencing factors of MACEs in *** The T2DM+ACS group showed higherγ-GGT,total cholesterol,low-density lipoprotein cholesterol(LDL-C)and glycosylated hemoglobin(HbA1c)and lower TBIL and high-density lipoprotein cholesterol levels than the T2DM and ACS groups(P<0.05).Based on univariate analysis,the event and nonevent groups were significantly different in age(t=3.3612,P=0.0011),TBIL level(t=3.0742,P=0.0028),γ-GGT level(t=2.6887,P=0.0085),LDL-C level(t=2.0816,P=0.0401),HbA1c level(t=2.7862,P=0.0065)and left ventricular ejection fraction(LEVF)levels(t=3.2047,P=0.0018).Multivariate logistic regression analysis further identified that TBIL level and LEVF level were protective factor for MACEs,and age andγ-GGT

关键词： Acute coronary syndrome Type-2 diabetes mellitus Total bilirubin Major adverse cardiovascular events

Influence of powder oxidation on powder properties and formability in H13 hot-work steels processed by electron beam melting

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Journal of Iron and Steel Research International 2024年第4期31卷 924-932页

作者： wei Liu Yan Wang Li-xiong han Ying-kang wei Hui-ping Tang Shi-feng Liu School of Metallurgical Engineering Xi'an University of Architecture and TechnologyXi'an 710055ShaanxiChina School of Engineering Zhejiang University City CollegeHangzhou 310015ZhejiangChina

The oxygen content of metal powder is decisive for the recyclability of *** research on the effect of oxygen content on powder properties and material formability has practical significance for economical production with additive manufacturing while preventing the waste of ***,we deliberately oxidized the powder by baking at high temperature to increase the oxygen content in the powder and gave the calculation method of the oxygen content in the powder oxidation *** majority of oxygen element was found in the oxide particles in the powder and the oxide flm on the powder surface,which did affect the flowability of the *** is worth noting that the increase in the oxygen content does not change the phase of H13 steel,but it can promote the molten pool flow and obtain a smoother *** increase in the oxygen content in the powder is not the decisive factor for the formability and defects of the printed *** is the combined effect of the powder deformation,the increase in the oxygen content,and the impurity pollution after repeated use,which leads to the limitation of repeated utilization of the powder.

关键词： Additive manufacturing Electron beam melting H13 steel powder-Powder oxidation

Simulation study of the performance of the Very Large Area gamma-ray Space Telescope

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Nuclear Science and Techniques 2024年第9期35卷 1-17页

作者： Xu Pan wei Jiang Chuan Yue Shi-Jun Lei Yu-Xin Cui qiang Yuan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China

The Very Large Area gamma-ray Space Telescope(VLAST)is a mission concept proposed to detect gamma-ray photons through both Compton scattering and electron–positron pair production mechanisms,thus enabling the detection of photons with energies ranging from MeV to *** project aims to conduct a comprehensive survey of the gamma-ray sky from a low-Earth orbit using an anti-coincidence detector,a tracker detector that also serves as a low-energy calorimeter,and a high-energy imaging *** developed a Monte Carlo simulation application of the detector using the GEANT4 toolkit to evaluate the instrument performance,including the effective area,angular resolution,and energy resolution,and explored specific optimizations of the detector *** simulation-based analysis indicates that the current design of the VLAST is physically feasible,with an acceptance above 10 m^(2)sr which is four times larger than that of the Fermi-LAT,an energy resolution better than 2%at 10 GeV,and an angular resolution better than 0.2◦at 10 *** VLAST project promises to make significant contributions to the field of gamma-ray astronomy and enhance our understanding of the cosmos.

关键词： Space astronomy Gamma-ray telescope Calorimeter Monte Carlo simulation

Quantum key distribution over a mimicked dynamic-scattering channel

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Science China(Information Sciences) 2024年第4期67卷 323-330页

作者： Qi-hang LU Fang-Xiang WANG wei CHEN Hai-Yang FU Yin-Jie LU Shuang WANG De-Yong HE Zhen-qiang YIN Guang-Can GUO Zheng-Fu han CAS Key Laboratory of Quantum Information University of Science and Technology of China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of China Hefei National Laboratory University of Science and Technology of China

Free-space quantum key distribution(QKD) plays an important role in the global quantum network. However, free space channels suffer from the atmospheric turbulence and scattering effects of haze,fog, and dust, which significantly weaken the performance of QKD or even block the secure quantum ***, we prove the performance of QKD over a dynamic scattering channel can be enhanced significantly using a fast wavefront shaping technique. The system achieves on average 10-dB enhancement of quantum transmission efficiency and establishes a secure quantum link for QKD. Our work demonstrates the feasibility of QKD through free-space dynamic scattering channels and enhances the deployment capability of complex-channel QKD system.

关键词： quantum key distribution free space channel channel turbulence channel scattering wavefront shaping

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中波红外光学系统被动无热化设计及测试

红外与激光工程 2009年第4期38卷 687-691页

作者：李华韩维强沈忙作中国科学院光电技术研究所四川成都610209

温度变化对红外光学系统的成像质量有很大影响。根据中波红外光学系统工作环境要求,分析了导致光学系统成像质量下降的主要因素,推导出同时消热差和消色差的材料组合公式,采用结构件为铝,光学材料为AMTIR-1和Ge组合消热差,设计了光学被... 详细信息

温度变化对红外光学系统的成像质量有很大影响。根据中波红外光学系统工作环境要求,分析了导致光学系统成像质量下降的主要因素,推导出同时消热差和消色差的材料组合公式,采用结构件为铝,光学材料为AMTIR-1和Ge组合消热差,设计了光学被动无热化中波红外光学系统,在-40～60℃温度范围内系统成像质量达到衍射极限,离焦量在一倍焦深以内。为实际考核集成了探测器后中波红外系统的无热效果,建立了无热化光学系统测试平台,对高温箱内的中波红外系统进行测试,采集探测器输出的数字图像,在3×3像素窗口内计算单像素的能量集中度,60℃时的单像素能量集中度下降到20℃的89.3%,测试结果表明:系统具有很好的成像质量和无热效果。

关键词：中波红外光学设计无热化设计热测试

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

Discriminative explicit instance selection for implicit discourse relation classification

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Frontiers of Computer Science 2024年第4期18卷 129-138页

作者： wei SONG Hongfei han Xu han Miaomiao CHENG Jiefu GONG Shijin WANG Ting LIU Information Engineering College Capital Normal UniversityBeijing 100048China iFLYTEK AI Research Institute Hefei 230088China Research Center for Social Computing and Information Retrieval Harbin Institute of TechnologyHarbin 150006China

Discourse relation classification is a fundamental task for discourse analysis,which is essential for understanding the structure and connection of *** discourse relation classification aims to determine the relationship between adjacent sentences and is very challenging because it lacks explicit discourse connectives as linguistic cues and sufficient annotated training *** this paper,we propose a discriminative instance selection method to construct synthetic implicit discourse relation data from easy-to-collect explicit discourse *** expanded instance consists of an argument pair and its sense *** introduce the argument pair type classification task,which aims to distinguish between implicit and explicit argument pairs and select the explicit argument pairs that are most similar to natural implicit argument pairs for data *** also propose a simple label-smoothing technique to assign robust sense labels for the selected argument *** evaluate our method on PDTB 2.0 and PDTB *** results show that our method can consistently improve the performance of the baseline model,and achieve competitive results with the state-of-the-art models.

关键词： discourse analysis PDTB discourse relation implicit discourse relation classification data expansion

An improved elastoplastic model for rocks and application to cyclic loading and unloading triaxial compression tests

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Acta Mechanica Sinica 2024年第8期40卷 179-193页

作者： Qiuxin Gu qiang Zhang Yapeng Li Peinan Wu Guilei han State Key Laboratory for Geomechanics and Deep Underground Engineering School of Mechanics and Civil EngineeringChina University of Mining and TechnologyXuzhou221116China North China Engineering Investigation Institute Shijiazhuang050021China

The recoverable strain of rock is completely classified as elastic strain in the conventional elastic-plastic theory,which often results in poor agreement between theoretical and experimental *** work proposes an improved elastoplastic model of rock materials considering the evolutions of crack deformation and elastic modulus to better characterize the nonlinear mechanical behavior of rock in the post-peak *** this model,the recoverable strain is assumed to be a combination of elastic and crack strain,and the constitutive relationship between crack strain and rock stress is *** on the proposed assumption,the evolutions of the mechanical parameters including strength parameters,elastic,plastic,and crack deformation parameters versus the plastic strain and confining stress were *** developed elastoplastic model was validated by comparing the theoretical values with the results of the triaxial cyclic loading and unloading *** theoretical calculation results show a good agreement with the laboratory test,which indicates that the improved elastoplastic model can effectively reflect the nonlinear mechanical behavior of the rock *** research results are expected to provide a valuable reference for further understanding the evolution of rock crack deformation.

关键词： Crack strain Elastic modulus deterioration Novel elastoplastic model Model validation