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面向Web的地下洞室群模型加载与渲染优化设计

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人民长江 2024年第4期55卷 178-183页

作者：张澍张歆长江勘测规划设计研究有限责任公司湖北武汉430010 长江水利委员会长江流域水土保持监测中心站湖北武汉430010

为解决BIM大规模三维场景给WebGL管线带来的渲染压力,结合水电站地下洞室群的结构、分布特点对数据动态调度策略进行了调整和优化。通过对比分析BIM和GIS中的LOD处理方式,设计了兼顾模型详细程度和发展程度的双重LOD处理机制;通过研究... 详细信息

为解决BIM大规模三维场景给WebGL管线带来的渲染压力,结合水电站地下洞室群的结构、分布特点对数据动态调度策略进行了调整和优化。通过对比分析BIM和GIS中的LOD处理方式,设计了兼顾模型详细程度和发展程度的双重LOD处理机制;通过研究传统金字塔型索引的结构特点和空间划分方式,设计了综合多种树结构的能够自动调整边界的空间索引结构。在此基础上设计了基于渐近加载的动态调度算法,测试表明该方法提高了大规模BIM模型在WebGL上的渲染效率和稳定性。

关键词：地下洞室群模型加载模型渲染 BIM LOD WebGL Cesium

Compound extreme inundation risk of coastal wetlands caused by climate change and anthropogenic activities in the Yellow River Delta,China

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Advances in Climate Change Research 2024年第1期15卷 134-147页

作者： Xiao-Li WANG Ai-Qing FENG Xi-Yong HOU Qing-Chen CHAO Bai-Yuan SONG Yu-Bin LIU Qi-Guang WANG He XU Yu-xin zhang Dong Li Li-Jie DONG Yu GUO CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China Shandong Key Laboratory of Coastal Environmental Processes Yantai 264003China China Meteorological Administration Key Laboratory for Climate Prediction Studies National Climate CentreBeijing 100081China Tongji Urban Planning Design Research Institute Shanghai 200092China School of Geography and Tourism Qilu Normal UniversityJinan 250200China China Meteorological Administration Training Centre China Meteorological AdministrationBeijing 10008China University of Chinese Academy of Sciences Beijing 100049China Marine Science and Technology College Zhejiang Ocean UniversityZhoushan 316022China

The coastal wetlands of the Yellow River Delta(YRD)in China are crucial for their valuable resources,environmental significance,and economic ***,these wetlands are also vulnerable to the dual threats of climate change and human *** substantial attention to the historical shifts in YRD's coastal wetlands,uncertainties remain regarding their future trajectory in the face of compound risks from climate change and anthropogenic *** on a range of remote sensing data sources,this study undertakes a comprehensive investigation into the evolution of YRD's coastal wetlands between 2000 and ***,the potential fate of coastal wetlands is thoroughly analyzed through the Land Use/Cover Change(LUCC)simulation using System Dynamic-Future Land Use Simulation(SD-FLUS)model and the extreme water levels projection integrated future sea-level rise,storm surge,and astronomical high tide in 2030,2050,and 2100 under scenarios of SSP1-2.6,SSP2-4.5,and *** revealed that YRD's coastal wetlands underwent a marked reduction,shrinking by 1688.72 km²from 2000 to *** decline was mostly attributed to the substantial expansion in the areas of artificial wetlands(increasing by 823.78 km2),construction land(increasing by 767.71 km²),and shallow water(increasing by 274.58 km²).Looking ahead to 2030-2100,the fate of coastal wetlands appears to diverge based on different *** the SSP1-2.6 scenario,the area of coastal wetland is projected to experience considerable *** contrast,the SSP5-8.5 scenario anticipates a notable decrease in coastal *** to the inundated area suffered from the current extreme water levels,the study projects a decrease of 6.8%-10.6%in submerged coastal wetlands by 2030 and 9.4%-18.2%by 2050 across all *** 2100,these percentages are projected to decrease by 0.4%(SSP2-4.5)and 27.1%(SSP5-8.5),but increase by 35.7%(SSP1-2.6).Results suggest that coastal wetlands in th

关键词： Climate change Anthropogenic activities Compound extreme risk Coastal wetlands Yellow River Delta

出版业高质量发展目标之创新发展——以新质生产力推动出版业高质量发展

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编辑之友 2024年第2期 29-35,53页

作者：方卿张新新武汉大学人文社会科学研究院湖北武汉430072 武汉大学信息管理学院湖北武汉430072 上海理工大学出版印刷与艺术设计学院上海200093

创新发展是基于新发展理念的出版业高质量发展目标的第一向度。出版业的创新发展,一是要推动出版管理体制机制创新,提升出版治理效能,促进出版治理体系现代化;二是要推动出版运行机制创新,构建文化特色鲜明的现代出版企业制度;三是要推... 详细信息

创新发展是基于新发展理念的出版业高质量发展目标的第一向度。出版业的创新发展,一是要推动出版管理体制机制创新,提升出版治理效能,促进出版治理体系现代化;二是要推动出版运行机制创新,构建文化特色鲜明的现代出版企业制度;三是要推动出版要素集聚创新,提升出版新质生产力,形成政府引导、市场导向、产学研用相衔接的出版协同创新体系。

关键词：出版高质量发展出版创新发展新质生产力数据出版智能出版

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All-sky Guide Star Catalog for CSST

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Research in Astronomy and Astrophysics 2024年第4期24卷 35-59页

作者： Hui-Mei Feng Zi-Huang Cao Man I Lam Ran Li Hao Tian Da-Yi Yin Yuan-Yu Yang xin zhang Dong-Wei Fan Yi-Qiao Dong xin-Feng Li Wei Wang Long Li Hugh RAJones Yi-Han Tao Jia-Lu Nie Pei-Pei Wang Mao-Yuan Liu He-jun Yang Chao Liu Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of ChineseAcademy of Sciences Beijing 100049China Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai200083China Technology and Engineering Center for Space Utilization.Chinese Academy of Sciences Beijing 100094China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Centre for Astrophysics University of HertfordshireHatfieldUK Beijing University of Technology Beijing 100124China

The China Space Station Telescope(CSST)is a two-meter space telescope with multiple back-end *** Fine Guidance Sensor(FGS)is an essential subsystem of the CSST Precision Image Stability System to ensure the required absolute pointing accuracy and line-of-sight *** this study,we construct the Main Guide Star Catalog for *** accomplish this,we utilize the information about the FGS and object information from the Gaia Data Release *** provide an FGS instrument magnitude and exclude variables,binaries,and high proper motion stars from the catalog to ensure uniform FGS guidance ***,we generate a HEALPix index,which provides a hierarchical tessellation of the celestial sphere,and employ the Voronoi algorithm to achieve a homogeneous distribution of stars across the *** distribution ensures adequate coverage and sampling of the *** performance of the CSST guide star catalog was assessed by simulating the field of view of the FGS according to the CSST mock survey strategy *** analysis of the results indicates that this catalog provides adequate coverage and *** catalog's performance meets the FGS requirements,ensuring the functioning of the FGS and its guidance capabilities.

关键词： catalogs astrometry instrumentation:detectors

Modified technical protocol for single-port laparoscopic appendectomy using needle-type grasping forceps for acute simple appendicitis:A case report

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World Journal of Gastrointestinal Surgery 2024年第10期16卷 3328-3333页

作者： Yang Chen Zong-Qi Fan xin-Ao Fu Xiao-xin zhang Jie-Qing Yuan Shi-Gang Guo Department of Gastrointestinal Surgery Chaoyang Central HospitalChina Medical UniversityChaoyang 122000Liaoning ProvinceChina Department of Gastrointestinal Surgery Chaoyang Central HospitalPostgraduate Training Base of China Medical University and Jinzhou Medical UniversityChaoyang 122000Liaoning ProvinceChina

BACKGROUND Because of the mild inflammatory status in acute uncomplicated appendicitis,our team developed a novel technical protocol for single-port laparoscopic appendec-tomy using needle-type grasping forceps(SLAN)and achieved positive clinical ***,the intraoperative procedure lacked stability and fluency due to a series of problems highlighted by the small incision design of the proto-col(only 1 cm long).Therefore,there is a growing clinical demand to further opti-mize the SLAN *** SUMMARY An adult male patient was admitted for persistent right lower abdominal pain with preoperative computed tomography findings suggestive of appendicitis accompanied by localized peritonitis.A modified technical protocol for SLAN based on minimally invasive surgical principles was used,and the patient was confirmed to have acute simple appendicitis by postoperative pathological *** recovery was uneventful,and no postoperative complications,such as incision infection or severe incision pain,were *** patient was discharged successfully on postoperative day *** The modified technical protocol of SLAN may be a new minimally invasive surgical alternative for patients with acute simple appendicitis.

关键词： Acute appendicitis Single-port laparoscopy Appendectomy Minimally invasive surgery Case report

A New Method for Monitoring Scattered Stray Light of an Inner-occulted Coronagraph

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Research in Astronomy and Astrophysics 2024年第2期24卷 216-227页

作者： Da-Yang Liu Hong-xin zhang Ming-Zhe Sun Zheng-Hua Huang Li-Dong Xia Wei-xin Liu Hui Fu Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

The scattered stray light of a coronagraph is a type of stray light that is generated by the objective lens as its surface defects are irradiated by *** defects mainly include dust and blemishes on the lens surface,microroughness of the lens surface,and impurity and inhomogeneity of the *** the other types of relatively stable defects introduced when the objective lens is being manufactured,the scattered stray light caused by dusts on the lens surface is difficult to quantify accurately due to the disorder and randomness of the dust *** contribution of this type of stray light to the overall stray light level is difficult to determine through simulations and *** can result in continuous deterioration of the stray light level of a coronagraph and thus affect the observation capabilities of the *** solve this issue,through analyzing the forming mechanism of scattered stray light and ghost image generated by the inner-occulted coronagraph,we propose a novel method to monitor the scattered stray light from dusts by utilizing different stray light correlation *** this method,we first simulate and measure the level of stray light from the ghost image of the objective lens,and then determine the flux ratio of scattered light and ghost image on the conjugate *** the flux ratio varies with the accumulation of dusts on the lens surface,it remains constant on the image ***,the level of dust scattering light on the image plane can be obtained by using this ratio together with the level of ghost image stray *** accuracy of this method has been validated in a laboratory by applying the objective lens with numerous surface cleanliness levels.

关键词： Sun corona-Sun atmosphere-instrumentation miscellaneous-methods analytical-techniques image processing

Bethe ansatz solutions of the 1D extended Hubbard-model

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Communications in Theoretical Physics 2024年第4期76卷 43-50页

作者：侯海洋孙佩乔艺许小甜张鑫杨涛 Institute of Modern Physics Northwest UniversityXian 710127China Shaanxi Key Laboratory for Theoretical Physics Frontiers Xian 710127China Beijing National Laboratory for Condensed Matter Institute of Physics Chinese Academy of SciencesBeijing 100190China

We construct an integrable 1D extended Hubbard model within the framework of the quantum inverse scattering *** the help of the nested algebraic Bethe ansatz method,the eigenvalue Hamiltonian problem is solved by a se... 详细信息

关键词： quantum integrable system Bethe ansatz T-Q relation Hubbard model

关中平原城市群生态系统服务时空特征及生态功能区划分

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干旱区地理 2024年第9期47卷 1587-1595页

作者：张鑫张丹张广森宋玫同济大学建筑与城市规划学院上海200092 西安建筑科技大学建筑学院陕西西安710054 青岛市政工程公司山东青岛266555 青岛热电燃气公司山东青岛266555

量化区域生态系统服务的时空分布格局,分析权衡/协同关系,识别生态系统服务簇,结合各服务簇内的功能特征,划定生态功能分区,有利于加强区域生态系统管理。以关中平原城市群为例,对2000—2020年的5种生态系统服务进行计算,运用K-means聚... 详细信息

量化区域生态系统服务的时空分布格局,分析权衡/协同关系,识别生态系统服务簇,结合各服务簇内的功能特征,划定生态功能分区,有利于加强区域生态系统管理。以关中平原城市群为例,对2000—2020年的5种生态系统服务进行计算,运用K-means聚类分析对服务簇进行识别,确定主导服务功能并实现生态功能分区的划分。结果表明:(1)粮食生产量和土壤保持量呈现先增加后减少的趋势;产水量呈现先迅速增加后缓慢增加的趋势;生境质量和碳固持量均呈现较轻幅度的减少趋势。粮食生产量高值区主要集中在研究区中部和东北部;土壤保持量的高值区主要集中在南部和西部;生境质量和碳固持量的高值区主要集中在南部。(2)粮食生产量与其他服务均呈现权衡关系,土壤保持量与生境质量、土壤保持量与碳固持量、生境质量与碳固持量之间均呈现协同关系,不同服务间相关关系的强弱会随着时间的变化而变化。(3)生态功能分区识别为粮食主产区、生态保育区、重要城市区和生态均衡区。研究结果对于维持生态系统的平衡和经济的可持续发展至关重要,对于促进关中平原城市群不同生态功能分区的生态系统管理具有指导意义。

关键词：生态系统服务簇权衡协同 K-means聚类关中平原城市群

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基于电容自然充电换相的混合式直流断路器设计与仿真

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电工技术学报 2024年第11期39卷 3510-3521页

作者：范兴明李涛张鑫桂林电子科技大学机电工程学院桂林541004

以晶闸管作为主断器件是降低混合式直流断路器造价和技术难度的手段之一,电容电压是此类直流断路器能够顺利开断直流故障的关键影响因素。现有结构中电容大多为预充电型,但预充电方式和电容电压的维持较为复杂。因此,该文提出一种基于... 详细信息

以晶闸管作为主断器件是降低混合式直流断路器造价和技术难度的手段之一,电容电压是此类直流断路器能够顺利开断直流故障的关键影响因素。现有结构中电容大多为预充电型,但预充电方式和电容电压的维持较为复杂。因此,该文提出一种基于电容自然充电换相的混合式直流断路器,利用母线电压与预充电电容的电压差值实现电容的预充电和电容电压的自动维持,从而保证断路器的开断能力。此外该断路器还具备二次开断能力,可以满足极短时间内重复开断的需求。针对所提断路器的工作过程和元器件参数进行了详细的理论推导,基于PSCAD/EMTDC建立单端等效和四端柔性直流电网模型验证了所提结构的适用性。最后与其他方案进行比较,结果表明,所提方案在开断速度、电容预充电方式和二次开断方面具备一定优势。

关键词：混合式直流断路器晶闸管预充电二次开断