厘清景观格局变化与洪枯径流的关系,对流域生态建设和水资源调控的协同推进具有重要支撑作用。以我国生态脆弱的三峡库区东里河流域为例,综合运用SWAT(Soil and Water Assessment Tool)模型、景观格局指数和随机森林等方法,从全流域和...厘清景观格局变化与洪枯径流的关系,对流域生态建设和水资源调控的协同推进具有重要支撑作用。以我国生态脆弱的三峡库区东里河流域为例,综合运用SWAT(Soil and Water Assessment Tool)模型、景观格局指数和随机森林等方法,从全流域和子流域角度分析了景观格局变化的洪枯径流效应,从景观组成和景观空间配置等多因素角度揭示了洪枯径流驱动机制。结果表明:(1)2000—2020年,全流域优势景观为林地和耕地,面积分别增加了3.76%和1.82%,景观聚集度上升,景观多样性和复杂程度下降;子流域优势景观与全流域基本一致,但斑块密度(PD)、最大斑块指数(LPI)和蔓延度指数(CONTAG)变化更为剧烈。(2)相比2000年,2020年景观格局下全流域洪枯径流以下降为主,最大1d径流(Max1d)下降了4.44%,枯水径流降幅均超40%。典型子流域的洪水径流变幅均高于全流域,而枯水径流变幅与全流域相当。(3)2000—2020年,景观格局对洪枯径流的调节能力减弱,其中景观组成的贡献率下降了0.84%—7.39%,景观空间配置的贡献率下降了1.63%—3.89%,这主要是因流域林草景观组合衰退,以及景观呈聚合发展所致。研究结果可加深对流域景观格局演变和生态水文过程的理解,亦可为流域生态建设和生态修复提供科学依据。展开更多
The Makran accretionary wedge has the smallest subduction angle among any accretionary prism in the world. The factors controlling the spacing and morphological development of its deep thrust faults, as well as the fo...The Makran accretionary wedge has the smallest subduction angle among any accretionary prism in the world. The factors controlling the spacing and morphological development of its deep thrust faults, as well as the formation mechanism of shallow normal faults, remain unclear. Meanwhile, the factors affecting the continuity of plane faults must be comprehensively discussed. Clarifying the development characteristics and deformation mechanisms of the Makran accretionary wedge is crucial to effectively guide the exploration of gas hydrate deposits in the area. This study aims to interpret seismic data to identify typical structures in the Makran accretionary wedge, including deep imbricate thrust faults, shallow and small normal faults, wedge-shaped piggyback basins, mud diapirs with fuzzy and disorderly characteristics of reflection, décollements with a northward tilt of 1° – 2°, and large seamounts. Physical simulation-based experiments are performed to comprehensively analyze the results of the plane, section, and slices of the wedge. Results reveal that the distances between and shapes of thrust faults in the deep parts of the Makran accretionary wedge are controlled by the bottom décollement. The uplift of the thrust fault-related folds and the upwelling of the mud diapirs primarily contribute to the formation of small normal faults in the shallow part of the area. The mud diapirs originate from plastic material at the bottom, while those that have developed in the area near the trench are larger. Seamounts and mud diapirs break the continuity of fault plane distribution.展开更多
The relentless progress in the research of geographic spatial data models and their application scenarios is propelling an unprecedented rich Level of Detail(LoD)in realistic 3D representation and smart cities.This pu...The relentless progress in the research of geographic spatial data models and their application scenarios is propelling an unprecedented rich Level of Detail(LoD)in realistic 3D representation and smart cities.This pursuit of rich details not only adds complexity to entity models but also poses significant computational challenges for model visualization and 3D GIS.This paper introduces a novel method for deriving multi-LOD models,which can enhance the efficiency of spatial computing in complex 3D building models.Firstly,we extract multiple facades from a 3D building model(LoD3)and convert them into individual semantic facade models.Through the utilization of the developed facade layout graph,each semantic facade model is then transformed into a parametric model.Furthermore,we explore the specification of geometric and semantic details in building facades and define three different LODs for facades,offering a unique expression.Finally,an innovative heuristic method is introduced to simplify the parameterized facade.Through rigorous experimentation and evaluation,the effectiveness of the proposed parameterization methodology in capturing complex geometric details,semantic richness,and topological relationships of 3D building models is demonstrated.展开更多
目的了解舟山市某医院男性精神分裂症患者再住院情况及影响因素,并构建列线图模型。方法采用回顾性研究方法,选取2022年1月至12月在舟山市第二人民医院接受住院治疗的183例男性精神分裂症患者为研究对象,根据患者住院次数分为再住院组(...目的了解舟山市某医院男性精神分裂症患者再住院情况及影响因素,并构建列线图模型。方法采用回顾性研究方法,选取2022年1月至12月在舟山市第二人民医院接受住院治疗的183例男性精神分裂症患者为研究对象,根据患者住院次数分为再住院组(住院次数≥2次)和未再住院组(住院次数为1次)。采用t检验或χ2检验对两组患者的资料进行单因素分析;采用多因素Logistic回归分析探讨精神分裂症患者1年内再住院的影响因素,并建立列线图预测模型。结果183例精神分裂症患者再住院率为49.18%;病程、首次住院时间、吸烟史及饮酒史是再住院的独立危险因素(P<0.05);列线图模型的受试者操作特征曲线下面积(area under the curve,AUC)为76.53。结论舟山市第二人民医院男性精神分裂症患者再住院率较高,病程、首次住院时间、吸烟及饮酒史是精神分裂症患者1年内再住院的独立风险因素,建立列线图预测模型有望评估精神分裂症患者再住院高危因素并实施针对性的干预措施以改善患者的生命质量。展开更多
文摘厘清景观格局变化与洪枯径流的关系,对流域生态建设和水资源调控的协同推进具有重要支撑作用。以我国生态脆弱的三峡库区东里河流域为例,综合运用SWAT(Soil and Water Assessment Tool)模型、景观格局指数和随机森林等方法,从全流域和子流域角度分析了景观格局变化的洪枯径流效应,从景观组成和景观空间配置等多因素角度揭示了洪枯径流驱动机制。结果表明:(1)2000—2020年,全流域优势景观为林地和耕地,面积分别增加了3.76%和1.82%,景观聚集度上升,景观多样性和复杂程度下降;子流域优势景观与全流域基本一致,但斑块密度(PD)、最大斑块指数(LPI)和蔓延度指数(CONTAG)变化更为剧烈。(2)相比2000年,2020年景观格局下全流域洪枯径流以下降为主,最大1d径流(Max1d)下降了4.44%,枯水径流降幅均超40%。典型子流域的洪水径流变幅均高于全流域,而枯水径流变幅与全流域相当。(3)2000—2020年,景观格局对洪枯径流的调节能力减弱,其中景观组成的贡献率下降了0.84%—7.39%,景观空间配置的贡献率下降了1.63%—3.89%,这主要是因流域林草景观组合衰退,以及景观呈聚合发展所致。研究结果可加深对流域景观格局演变和生态水文过程的理解,亦可为流域生态建设和生态修复提供科学依据。
基金funded by the National Natural Science Foundation of China(No.42076069).
文摘The Makran accretionary wedge has the smallest subduction angle among any accretionary prism in the world. The factors controlling the spacing and morphological development of its deep thrust faults, as well as the formation mechanism of shallow normal faults, remain unclear. Meanwhile, the factors affecting the continuity of plane faults must be comprehensively discussed. Clarifying the development characteristics and deformation mechanisms of the Makran accretionary wedge is crucial to effectively guide the exploration of gas hydrate deposits in the area. This study aims to interpret seismic data to identify typical structures in the Makran accretionary wedge, including deep imbricate thrust faults, shallow and small normal faults, wedge-shaped piggyback basins, mud diapirs with fuzzy and disorderly characteristics of reflection, décollements with a northward tilt of 1° – 2°, and large seamounts. Physical simulation-based experiments are performed to comprehensively analyze the results of the plane, section, and slices of the wedge. Results reveal that the distances between and shapes of thrust faults in the deep parts of the Makran accretionary wedge are controlled by the bottom décollement. The uplift of the thrust fault-related folds and the upwelling of the mud diapirs primarily contribute to the formation of small normal faults in the shallow part of the area. The mud diapirs originate from plastic material at the bottom, while those that have developed in the area near the trench are larger. Seamounts and mud diapirs break the continuity of fault plane distribution.
基金National Natural Science of China(No.42201463)Guangxi Natural Science Foundation(No.2023GXNSFBA026350)+1 种基金Special Fund of Guangxi Science and Technology Base and Talent(Nos.Guike AD22035158,Guike AD23026167)Guangxi Young and Middle-aged Teachers’Basic Scientific Research Ability Improvement Project(No.2023KY0056).
文摘The relentless progress in the research of geographic spatial data models and their application scenarios is propelling an unprecedented rich Level of Detail(LoD)in realistic 3D representation and smart cities.This pursuit of rich details not only adds complexity to entity models but also poses significant computational challenges for model visualization and 3D GIS.This paper introduces a novel method for deriving multi-LOD models,which can enhance the efficiency of spatial computing in complex 3D building models.Firstly,we extract multiple facades from a 3D building model(LoD3)and convert them into individual semantic facade models.Through the utilization of the developed facade layout graph,each semantic facade model is then transformed into a parametric model.Furthermore,we explore the specification of geometric and semantic details in building facades and define three different LODs for facades,offering a unique expression.Finally,an innovative heuristic method is introduced to simplify the parameterized facade.Through rigorous experimentation and evaluation,the effectiveness of the proposed parameterization methodology in capturing complex geometric details,semantic richness,and topological relationships of 3D building models is demonstrated.
文摘目的了解舟山市某医院男性精神分裂症患者再住院情况及影响因素,并构建列线图模型。方法采用回顾性研究方法,选取2022年1月至12月在舟山市第二人民医院接受住院治疗的183例男性精神分裂症患者为研究对象,根据患者住院次数分为再住院组(住院次数≥2次)和未再住院组(住院次数为1次)。采用t检验或χ2检验对两组患者的资料进行单因素分析;采用多因素Logistic回归分析探讨精神分裂症患者1年内再住院的影响因素,并建立列线图预测模型。结果183例精神分裂症患者再住院率为49.18%;病程、首次住院时间、吸烟史及饮酒史是再住院的独立危险因素(P<0.05);列线图模型的受试者操作特征曲线下面积(area under the curve,AUC)为76.53。结论舟山市第二人民医院男性精神分裂症患者再住院率较高,病程、首次住院时间、吸烟及饮酒史是精神分裂症患者1年内再住院的独立风险因素,建立列线图预测模型有望评估精神分裂症患者再住院高危因素并实施针对性的干预措施以改善患者的生命质量。
