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The forecasting efficiency under different selected regions by Pattern Informatics Method and seismic potential estimation in the North-South Seismic Zone
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作者 Weixi Tian Yongxian Zhang 《Earthquake Science》 2024年第4期368-382,共15页
In 2022,four earthquakes with M_(S)≥6.0 including the Menyuan M_(S)6.9 and Luding M_(S)6.8 earthquakes occurred in the North-South Seismic Zone(NSSZ),which demonstrated high and strong seismicity.Pattern Informatics(... In 2022,four earthquakes with M_(S)≥6.0 including the Menyuan M_(S)6.9 and Luding M_(S)6.8 earthquakes occurred in the North-South Seismic Zone(NSSZ),which demonstrated high and strong seismicity.Pattern Informatics(PI)method,as an effective long and medium term earthquake forecasting method,has been applied to the strong earthquake forecasting in Chinese mainland and results have shown the positive performance.The earthquake catalog with magnitude above M_(S)3.0 since 1970 provided by China Earthquake Networks Center was employed in this study and the Receiver Operating Characteristic(ROC)method was applied to test the forecasting efficiency of the PI method in each selected region related to the North-South Seismic Zone systematically.Based on this,we selected the area with the best ROC testing result and analyzed the evolution process of the PI hotspot map reflecting the small seismic activity pattern prior to the Menyuan M_(S)6.9 and Luding M_(S)6.8 earthquakes.A“forward”forecast for the area was carried out to assess seismic risk.The study shows the following.1)PI forecasting has higher forecasting efficiency in the selected study region where the difference of seismicity in any place of the region is smaller.2)In areas with smaller differences of seismicity,the activity pattern of small earthquakes prior to the Menyuan M_(S)6.9 and Luding M_(S)6.8 earthquakes can be obtained by analyzing the spatio-temporal evolution process of the PI hotspot map.3)The hotspot evolution in and around the southern Tazang fault in the study area is similar to that prior to the strong earthquakes,which suggests the possible seismic hazard in the future.This study could provide some ideas to the seismic hazard assessment in other regions with high seismicity,such as Japan,Californi,Turkey,and Indonesia. 展开更多
关键词 Luding M_(s)6.8 and Menyuan M_(s)6.9 earthquake pattern Informatics Method North-south seismic Zone earthquake forecasting seismic activity pattern.
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基于三层B/S架构的企业信息化管理系统的设计
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作者 李迎国 《中国高新科技》 2024年第14期13-15,共3页
为解决企业管理系统中存在的数据冗余、不一致、数据同步效率低等问题,文章通过引入三层浏览器/服务器(B/S)架构模式,实现了对企业信息化管理系统的研究。该系统的设计主要包含数据库设计、系统管理、生产管理、统计报表等主要功能模块... 为解决企业管理系统中存在的数据冗余、不一致、数据同步效率低等问题,文章通过引入三层浏览器/服务器(B/S)架构模式,实现了对企业信息化管理系统的研究。该系统的设计主要包含数据库设计、系统管理、生产管理、统计报表等主要功能模块的设计。系统由浏览器向服务器发送请求,服务器接收请求并处理,然后将结果返回给浏览器。系统采用了MVC设计模式,将数据层、业务层和表示层分离开来,提高了可维护性、可扩展性和可重用性。该系统的应用不仅达到了数据远程共享的目的,还实现了对现骨干数据及报表的查询功能,可充分满足企业的信息化管理需求。 展开更多
关键词 浏览器/服务器架构 企业信息化 管理系统 MVC设计模式
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基于CLUE-S模型的浙江省土地利用结构变化趋势分析
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作者 王萍 林乐乐 +4 位作者 彭杨靖 黄治昊 宋超 张童 崔国发 《生态科学》 CSCD 北大核心 2024年第3期196-206,共11页
土地利用格局变化及未来发展情景对省域土地合理规划和生物多样性保护具有重要意义。以东部典型区域浙江省为例,根据浙江省2013和2018年两期精度500 m×500 m土地利用数据、浙江省陆地国家公园、国家级自然保护区数据,分别设置了土... 土地利用格局变化及未来发展情景对省域土地合理规划和生物多样性保护具有重要意义。以东部典型区域浙江省为例,根据浙江省2013和2018年两期精度500 m×500 m土地利用数据、浙江省陆地国家公园、国家级自然保护区数据,分别设置了土地利用结构和经济社会发展速率维持现状的情景、自然保护地体系建立情景和城市扩张情景。选取高程、坡度、人口等11种影响因素作为驱动因子,采用CLUE-S模型拟合浙江省2018年的土地利用覆被格局并判断拟合精度,进而模拟出三种情景下研究区2030年的土地利用格局演变。结果表明:1)Logistic二元回归分析结果ROC值均大于0.699,表明所选驱动因子对土地利用类型的解释能力较为准确。2)Kappa系数高达0.9460,表明模型能够准确的模拟浙江省土地利用分布格局;3)与2018年浙江省土地利用情况相比,2030年在不同情景下土地利用面积与空间分布均发生了一定的变化,土地利用结构和经济社会发展维持现状情景下建设用地持续扩张,建设用地面积增加16575 hm^(2),显著增加的区域主要位于杭州市郊和温州市郊。自然保护地体系建立情景下,林地、水域分别增加了15625、1600 hm^(2),耕地、草地和建设用地分别减少了1550、1700和13975 hm^(2),空间上都呈现均匀变化。城市扩张情景下,建设用地面积迅速增加145800 hm^(2),增加部分多数位于原有建设用地的外围。三种情景对比下,自然保护地体系建立情景是浙江省2030年最适宜的土地利用土地覆被格局。2030年浙江省在自然保护地体系建立情景下生态空间的面积最大,为6741925 hm^(2),年均增加速度为0.0192%。 展开更多
关键词 土地利用格局变化 驱动因子 情景模拟 CLUE-s模型
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基于PI方法的华北2019年以来3次M_(S)≥5.0地震回溯性预测研究
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作者 宋程 张永仙 +4 位作者 夏彩韵 毕金孟 张小涛 吴永加 徐小远 《地震》 CSCD 北大核心 2024年第2期120-134,共15页
本文应用图像信息(PI)方法对2023年山东平原M_(S)5.5地震、2021年江苏大丰海域M_(S)5.0地震和2020年河北古冶M_(S)5.1地震进行了回溯性预测研究。以华北局部(32°N~42°N,114°E~122°E)为研究区域,在网格尺度分别为0.5... 本文应用图像信息(PI)方法对2023年山东平原M_(S)5.5地震、2021年江苏大丰海域M_(S)5.0地震和2020年河北古冶M_(S)5.1地震进行了回溯性预测研究。以华北局部(32°N~42°N,114°E~122°E)为研究区域,在网格尺度分别为0.5°×0.5°和1.0°×1.0°且预测窗长为5 a的两组参数模型下,获取2019—2027年逐年滑动的预测窗热点演化图像。结果显示,当网格尺度为1.0°×1.0°时,PI热点效果优于0.5°×0.5°网格,且对平原地震和大丰海域地震的发震位置指示作用较好。当时间窗长和归一化阈值绝对值同时增大,个别窗口存在古冶地震的有效热点,但未找到热点能同时覆盖3个地震震中所在网格的参数模型。不同参数模型下的PI热点显示,未来3~4 a郯庐断裂带渤海段存在发生M_(S)≥5.0地震的风险。本文研究结果对于华北局部地区M_(S)≥5.0地震危险性分析具有一定的参考意义。 展开更多
关键词 2023年平原M_(s)5.5地震 2021年大丰海域Ms5.0地震 2020年古冶Ms5.1地震 图像信息方法 热点迁移
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Quantum Algorithm for Mining Frequent Patterns for Association Rule Mining
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作者 Abdirahman Alasow Marek Perkowski 《Journal of Quantum Information Science》 CAS 2023年第1期1-23,共23页
Maximum frequent pattern generation from a large database of transactions and items for association rule mining is an important research topic in data mining. Association rule mining aims to discover interesting corre... Maximum frequent pattern generation from a large database of transactions and items for association rule mining is an important research topic in data mining. Association rule mining aims to discover interesting correlations, frequent patterns, associations, or causal structures between items hidden in a large database. By exploiting quantum computing, we propose an efficient quantum search algorithm design to discover the maximum frequent patterns. We modified Grover’s search algorithm so that a subspace of arbitrary symmetric states is used instead of the whole search space. We presented a novel quantum oracle design that employs a quantum counter to count the maximum frequent items and a quantum comparator to check with a minimum support threshold. The proposed derived algorithm increases the rate of the correct solutions since the search is only in a subspace. Furthermore, our algorithm significantly scales and optimizes the required number of qubits in design, which directly reflected positively on the performance. Our proposed design can accommodate more transactions and items and still have a good performance with a small number of qubits. 展开更多
关键词 Data Mining Association Rule Mining Frequent pattern Apriori Algorithm Quantum Counter Quantum Comparator Grover’s search Algorithm
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试论积极反叙实句式“要是S就好了”
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作者 李昕颐 宗守云 《中北大学学报(社会科学版)》 2024年第1期123-129,共7页
句式“要是S就好了”属于积极反叙实用法,在句法、语义、语用层面有其独特之处:句法上,“要是”为假设连词,口语化语体色彩较高。S为反叙实小句,主要由主谓小句和VP小句构成,适合表达简洁内容,具有口语化特点。“就好了”为语气词,根据... 句式“要是S就好了”属于积极反叙实用法,在句法、语义、语用层面有其独特之处:句法上,“要是”为假设连词,口语化语体色彩较高。S为反叙实小句,主要由主谓小句和VP小句构成,适合表达简洁内容,具有口语化特点。“就好了”为语气词,根据情况不同分为纯粹虚拟语气词和最低条件语气词两种类型;语义上,“要是S就好了”是纯粹的积极反叙实句式,隐含对过去的遗憾、对现实的期待、对未来的盼望三种不同的语义价值;语用上,积极反叙实句式“要是S就好了”具有有利性,合乎社会规范,其语用价值在于表达虚拟愿望、复盘重构与反思、催生积极转变与进步。 展开更多
关键词 积极反叙实句式 “要是s就好了” 句法 语义 语用
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Design of a Landscape Device for Children from the Perspective of Embodied Cognition in the New Era
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作者 HU Bingbing 《Journal of Landscape Research》 2024年第5期5-9,共5页
In recent years,embodied cognition has ushered in a new research upsurge in the academic field,and has become a hot topic in the field of cognitive psychology.In this paper,from the perspective of embodied cognition,t... In recent years,embodied cognition has ushered in a new research upsurge in the academic field,and has become a hot topic in the field of cognitive psychology.In this paper,from the perspective of embodied cognition,the interaction ways of a landscape device for children were discussed to achieve a more real and harmonious interaction between children and scenes.The research data of embodied cognition used by children was analyzed,and the drawbacks and breakthrough points of current landscape devices for children were discussed.The core characteristics of children’s growth period were extracted to establish children’s interaction model and summarize the interactive design methods of landscape devices for children.Embodied cognition has become the most intuitive way for children to know and understand the environment,and plays a pivotal role in children’s growth.Based on embodied cognition principle and interactive behavior mode,the interactive design of a landscape device for children was studied,and three interactive design modes,including simple and convenient interaction mode,multi-sensory interaction mode and game natural interaction mode were summarized.On the basis of this research,relevant design practice and research were carried out to bring a new vision to the design of children’s landscape. 展开更多
关键词 Embodied cognition Children’s landscape Device design Interactive behavior pattern
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The Collaboratory for the Study of Earthquake Predictability in China:Experiment Design and Preliminary Results of CSEP2.0
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作者 ZHANG Shengfeng ZHANG Yongxian +3 位作者 Maximilian J.WERNER Kenny G.RAHAM David A.RHOADES JoséA.BAYONA 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第S01期94-97,共4页
Since the inaugural international collaboration under the framework of the Collaboratory for the Study of Earthquake Predictability(CSEP)in 2007,numerous forecast models have been developed and operated for earthquake... Since the inaugural international collaboration under the framework of the Collaboratory for the Study of Earthquake Predictability(CSEP)in 2007,numerous forecast models have been developed and operated for earthquake forecasting experiments across CSEP testing centers(Schorlemmer et al.,2018).Over more than a decade,efforts to compare forecasts with observed earthquakes using numerous statistical test methods and insights into earthquake predictability,which have become a highlight of the CSEP platform. 展开更多
关键词 earthquake forecasting seismicity modeling CsEP2.0 pattern Informatics(PI)algorithm long-to-intermediate-term forecast Relative Intensity(RI)algorithm Completeness Magnitude s test N test
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山新杨谷胱甘肽S-转移酶PdbGST基因的克隆与胁迫表达分析
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作者 平晓帆 遇文婧 黄颖 《林业科技》 2024年第3期33-40,共8页
在植物中,谷胱甘肽S-转移酶是一类多功能酶,能够在其响应非生物胁迫中发挥作用。为研究该基因在杨树中的功能,本研究克隆了山新杨谷胱甘肽S-转移酶基因Pdb GST及其启动子序列,对其进行生物信息学分析和表达特征分析。结果显示,Pdb GST... 在植物中,谷胱甘肽S-转移酶是一类多功能酶,能够在其响应非生物胁迫中发挥作用。为研究该基因在杨树中的功能,本研究克隆了山新杨谷胱甘肽S-转移酶基因Pdb GST及其启动子序列,对其进行生物信息学分析和表达特征分析。结果显示,Pdb GST基因的开放阅读框(ORF)全长666 bp,编码221个氨基酸,其形成的蛋白质相对分子质量为25.57 k Da,为稳定亲水性酸性蛋白,定位于细胞质中。系统进化分析表明,山新杨Pdb GST蛋白与山新杨中的XP_034926648蛋白的同源性最高。对克隆获取的2 000 bp启动子序列进行分析,结构显示该启动子序列中,含有多种响应非生物胁迫的顺式作用元件。荧光定量PCR分析显示Pdb GST基因在山新杨根部表达量最高,其次在山新杨叶部也有较高表达量,相反在山新杨顶芽中表达量最低。此外,对Pdb GST基因响应非生物胁迫分析显示,山新杨根部Pdb GST基因受诱导后即出现持续且大量的表达。 展开更多
关键词 山新杨 谷胱甘肽s-转移酶 非生物胁迫 表达模式
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基于CNN和D-S证据理论的多站协同多功能雷达工作模式识别方法
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作者 于旺 石艳 +1 位作者 宋吉烨 黄子纯 《电子信息对抗技术》 2024年第2期33-39,共7页
传统的多功能雷达工作模式识别方法主要利用单一电子侦察设备侦收的脉冲数据完成特征提取,其模型或算法的泛化能力不强。因此,提出基于卷积神经网络(Convolutional Neural Network,CNN)和D-S(Dempster-Shafer)证据理论的多站协同多功能... 传统的多功能雷达工作模式识别方法主要利用单一电子侦察设备侦收的脉冲数据完成特征提取,其模型或算法的泛化能力不强。因此,提出基于卷积神经网络(Convolutional Neural Network,CNN)和D-S(Dempster-Shafer)证据理论的多站协同多功能雷达工作模式识别方法。首先,利用轻量级CNN模型对不同方位、不同俯仰下侦察截获分选的脉冲幅度/波形单元数据进行自适应特征提取。其次,利用多站协同侦察系统通过D-S证据理论融合多站协同下不同侦察站点的Softmax分类器的分类结果,实现在差侦察条件下对不同空间方向上的多功能雷达工作模式快速准确识别。仿真验证结果表明,该方法相比于单侦察站条件下具有更好的识别性能。 展开更多
关键词 工作模式识别 卷积神经网络 D-s证据理论 多站协同
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URBAN COMPETITIVE PATTERN AND ITS CHANGES IN CHINA 被引量:5
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作者 DOU Wen-zhang LI Guo-ping +2 位作者 GAN Ying-jin WANG Li-ming YANG Kai-zhong(Department of Urban and Environmental Sciences, Peking University, Beijing 100871, P R. China) 《Chinese Geographical Science》 SCIE CSCD 2000年第2期105-112,共8页
With the national economy’s transition from a planning one to a market one, the factors affecting regional economic pattern has changed greatly. In this paper we first construct an index system for evaluating competi... With the national economy’s transition from a planning one to a market one, the factors affecting regional economic pattern has changed greatly. In this paper we first construct an index system for evaluating competitiveness of Chinese cities based on modern competitive advantage theory. With principal component analysis and cluster analysis methods, we compare the factors affecling cities’ integrated competitiveness in 1990 and 1997. We find that four major factors are capital (including investment, FDI and urban financial revenue ), urban ithestructure (transporiation and communication, urbanization level, education etc. ), industrial performance and structure, degree of market openness and that these factors have become more advanced and complicated since 1990. Most Chinese cities are transforming from productive factors-oriented type to investment-oriented type and a few are becoming innovation oriented. The integrated competitiveness is closely related to cities’ scale, urban function, regional policy and degree of market openness and displays an uneven spatial pattern. The difference between the south and the north and the difference between the west and the east co-exist bul the former has been more larger. Finally, we discuss the mechanism behind the pattern and attribute the unevenness to change of factors dominating the cities’ compehtiveness regional innovation capacity and geographical differenceof traditional culture. 展开更多
关键词 URBAN integrated COMPETITIVENEss COMPETITIVE pattern China’s CITIEs
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Forest landscape patterns dynamics of Yihe-Luohe river basin 被引量:4
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作者 DINGShengyan SHANGFude +2 位作者 QIANLexiang CAOXinxiang LIShuang 《Journal of Geographical Sciences》 SCIE CSCD 2003年第2期153-162,共10页
Based on the information from forest resources distribution maps of Luoning County of 1983 and 1999, six indices were used to analyze spatial patterns and dynamics of forest landscapes of t... Based on the information from forest resources distribution maps of Luoning County of 1983 and 1999, six indices were used to analyze spatial patterns and dynamics of forest landscapes of the typical region in the middle of the Yihe-Luohe river basin. These indices include patch number, mean patch area, fragment index, patch extension index, etc. The results showed that: (1) There was a rapid increase in the number of patch and total area from 1983 to 1999 in the study area. The fragment degree became very high. (2) The area of all the forest patch types had witnessed great changes. The fractal degree of each forest patch type became big from 1983 to 1999. The mean extension index of Robinia pseudoacacia forest, non-forest, shrub forest, sparse forest, and Quercus species forest increased rapidly, but that of economic forest became zero. The fractal dimension each showed that forest coverage has been promoted. (3) The changes of landscape patterns were different in different geomorphic regions. From 1983 to 1999 the vegetation cover area, the gross number and the density of patch, diversity and evenness of landscape were all reduced greatly in gullies and ravines, but the maximum area and the mean area of patch types were increased. In hilly region, both the forest cover area and the number of patch increased from 1983 to 1999, but the mean area of patch was reduced greatly. In mountain region, even though the area under forest canopy reduced from 1983 to 1999, the patch number was increased greatly, the mean area of all patch types was reduced, the extension index, diversity index and evenness index of landscape were all increased. Furthermore, because of different types of land use, human activity and terrain, the vegetation changes on northern and southern mountain slopes were different. According to these analyses, the main driving forces, such as the policies of management, market economy, influence of human activities etc. are brought out. 展开更多
关键词 FOREsT landscape pattern DYNAMICs geomorphic zone Yihe-Luohe river basin Luoning County CLC number:s718.5 Q948.2 P901
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Distribution Patterns of Medicinal Plants along an Elevational Gradient in Central Himalaya,Nepal 被引量:1
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作者 Maan B.ROKAYA Zuzana MÜNZBERGOVÁ +1 位作者 Mani R.SHRESTHA Binu TIMSINA 《Journal of Mountain Science》 SCIE CSCD 2012年第2期201-213,共13页
This study aimed to compare the distribution patterns and trends of plant parts used among different groups of medicinal plants, geographical regions,and between medicinal plants and all vascular plants.We used the pu... This study aimed to compare the distribution patterns and trends of plant parts used among different groups of medicinal plants, geographical regions,and between medicinal plants and all vascular plants.We used the published sources for elevation records of 2,331 medicinal plant species to interpolate presence between minimum and maximum elevations and estimated medicinal plant richness for each 100-m elevational band. Monte Carlo simulations were used to test whether differences in elevational distribution between different groups of medicinal plants were significant. Total number of medicinal plants as well as different groups showed unimodal relationship with elevation. The elevational distributions of medicinal plants significantly differ between regions and between medicinal plant groups.When comparing the richness of all medicinal plants to all vascular plants,Monte Carlo simulations indicated that the numbers of medicinal plants are higher than expected at low elevations.The highest richness of medicinal plants at low elevation could be possibly due to favorable environmental factors such as high temperature, rainfall,sunlight or due to higher density of human population and thus higher pressure on use of any plants in lower elevations. 展开更多
关键词 species richness Rapoport's elevational rule Mid-domain effect Randomization test Unimodal pattern HIMALAYA Nepal
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Change of Flood Patterns in China under the Influences of Climate Change and Human Activities 被引量:2
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作者 Yin Yixing Xu Youpeng Chen Ying 《Chinese Journal of Population,Resources and Environment》 2009年第3期67-71,共5页
Based on the flood affected area (FA) data of the provinces in China from 1950 to 2005, the article discusses the change of the flood patterns in China, and investigates its relationship with climate change and huma... Based on the flood affected area (FA) data of the provinces in China from 1950 to 2005, the article discusses the change of the flood patterns in China, and investigates its relationship with climate change and human activities. The flood center shifted from North China and the Yangtze-Huaihe basin in the 1950s towards the south, north and west of China, and located in the south of the Yangtze River and South China after the 1990s. The FA in the western provinces was continuously on the rise since the 1950s. There are two characteristics for the future flood pattem in China. The pattern of "flood in the south and drought in the north" depends on the north-south shift of the maximum rainfall region in eastern China. The flood intensification to the west of Hu Huanyong's line mainly results from the increase of rainfall, extreme precipitation and the melting of glaciers under the background of human activity magnification. 展开更多
关键词 flood pattern flood in the south and drought in the north Hu Huanyong's line climate change human activity
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Evolution Process of Urban Spatial Pattern in Hubei Province Based on DMSP/OLS Nighttime Light Data 被引量:4
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作者 ZHENG Wensheng RUN Jiying +2 位作者 ZHUO Rongrong JIANG Yupei WANG Xiaofang 《Chinese Geographical Science》 SCIE CSCD 2016年第3期366-376,共11页
This paper intends to investigate the urban spatial patterns of Hubei Province and its evolution from three different perspectives: urban nodes, urban connections and urban clusters. The research adopts nighttime ligh... This paper intends to investigate the urban spatial patterns of Hubei Province and its evolution from three different perspectives: urban nodes, urban connections and urban clusters. The research adopts nighttime light imagery of cities in Hubei Province, the viewpoint of ′point-axis-area′ in the ′point-axis system′ theory, and employs light index model, gravity model and social network analysis. The findings are as follows: 1) In terms of urban nodes, the urbanization process of Hubei has been carried out mainly on the basis of external expansion rather than internal increasing. The polarization trend of urban connection network is strengthening. 2) As for urban connections, the estimation of urban connections using light index model is capable of containing various actual flow, and the connections are getting increasingly closer. 3) In regard to urban groups, seven urban groups of varying sizes have formed. On that basis, three stable and relatively independent urban groups as the centers, namely Wuchang, Yichang and Xiangyang emerge as well. But the structures of ′Wuhan Metropolitan Area′, ′Yichang-Jingzhou-Jingmen City Group′ and ′Xiangyang-Shiyen-Suizhou City Group′, which are defined by local development strategy in Hubei Province, are different from the above three urban groups. 展开更多
关键词 Defence Meteorological satellite Program′s Operational Linescan system(DMsP/OLs urban spatial pattern point-axis-area Hubei Province China
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2021年玛多M_(S)7.4地震的PI热点特征回溯性预测研究 被引量:1
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作者 宋程 张永仙 +2 位作者 周少辉 毕金孟 徐小远 《地震研究》 CSCD 北大核心 2023年第2期226-236,共11页
应用图像信息(PI)方法研究2021年玛多M_(S)7.4地震前后的热点特征变化。以8 a预测窗长、0.8°×0.8°网格尺度为主要参数,获取2009—2028年逐年滑动的预测窗热点分布图像。结果显示:(1)在2009—2020年的5个连续回溯性预测... 应用图像信息(PI)方法研究2021年玛多M_(S)7.4地震前后的热点特征变化。以8 a预测窗长、0.8°×0.8°网格尺度为主要参数,获取2009—2028年逐年滑动的预测窗热点分布图像。结果显示:(1)在2009—2020年的5个连续回溯性预测窗口中,玛多地震的震中所在网格及其摩尔邻近网格持续存在密集热点,对发震地点指示作用较强。(2) 2014—2028年,多数预测窗口内玛多地震震中或摩尔邻近网格出现过PI热点;在最后3个连续预测窗口内(2019—2026年、2020—2027年、2021—2028年),震中附近出现密集深色热点且呈逐渐收缩的趋势,对发震紧迫性具有一定的指示意义。(3)综合2009年以来的热点演化图像可知,巴颜喀拉地块、柴达木地块、祁连地块和羌塘地块内都出现过热点,出现在巴颜喀拉地块与柴达木地块交界玛多县附近的热点频次高、颜色深、覆盖面较大,表明青藏块体内部巴颜喀拉地块中北缘地震活动性较强、相对发震风险较高。 展开更多
关键词 玛多M_(s)7.4地震 PI方法 热点 回溯性预测
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Study on Landscape Pattern Based on Landsat-8 in the Center of Chengdu City, China 被引量:1
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作者 Wei He Youyou Huang +2 位作者 Xin Dong Xianchun Yan Dengfei Li 《Journal of Environmental Protection》 2016年第7期1050-1056,共7页
Study on landscape spatial pattern in the center of Chengdu City is based on the Landsat-8 image by using 3S technique and spatial pattern analysis software Fragstats 3.3. The results showed that there covered an area... Study on landscape spatial pattern in the center of Chengdu City is based on the Landsat-8 image by using 3S technique and spatial pattern analysis software Fragstats 3.3. The results showed that there covered an area of 193.92 km<sup>2</sup> in the center of Chengdu City. 55.24% of the total area was made up of buildings, covering an area of 107.12 km<sup>2</sup>, and the overall landscape of impervious ground-based. There were 22,666 patches;29.67% of the patches were roads. The human interference of buildings, roads and green space was a maximum;fragmentation of the highest was green space. The fragmentation of overall urban landscape was high;the diversity was low;the value of Shannon’s diversity index was 0.63;the value of Shannon’s evenness index was 0.70. All kinds of landscape distribution were not balanced, and lack of connectivity. This research puts important reference for creating good urban landscape space and restoring the natural ecological environment in the western regions of China. 展开更多
关键词 Chengdu City Landscape pattern Urban Landscape 3s Technique Landscape Index
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Study On Pattern Design of Men's Tailored-suit Sleeve
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作者 李兴刚 李俊 《Journal of China Textile University(English Edition)》 EI CAS 2000年第4期34-39,共6页
Sleeve pattern design of men’ s tailored - suit is one of the most difficult problems of clothing pattern design. Based on the experimental studies of armhole girth, the difference of armhole width and crown height, ... Sleeve pattern design of men’ s tailored - suit is one of the most difficult problems of clothing pattern design. Based on the experimental studies of armhole girth, the difference of armhole width and crown height, crown angle, under sleeve curve’s diagonal line length, crown ease and its distribution rule, this paper mainly deals with the sleeve pattern design of tailored - suit for Chinese men. The influences of these factors are discussed and furthermore, some qualitative, quantifiable conclusions are drawn to design perfect pattern of men’ s tailored - suit sleeve. 展开更多
关键词 men’ s TAILORED - sUIT sLEEVE pattern design comfort
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Detection of Alzheimer’s disease onset using MRI and PET neuroimaging:longitudinal data analysis and machine learning 被引量:2
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作者 Iroshan Aberathne Don Kulasiri Sandhya Samarasinghe 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第10期2134-2140,共7页
The scientists are dedicated to studying the detection of Alzheimer’s disease onset to find a cure, or at the very least, medication that can slow the progression of the disease. This article explores the effectivene... The scientists are dedicated to studying the detection of Alzheimer’s disease onset to find a cure, or at the very least, medication that can slow the progression of the disease. This article explores the effectiveness of longitudinal data analysis, artificial intelligence, and machine learning approaches based on magnetic resonance imaging and positron emission tomography neuroimaging modalities for progression estimation and the detection of Alzheimer’s disease onset. The significance of feature extraction in highly complex neuroimaging data, identification of vulnerable brain regions, and the determination of the threshold values for plaques, tangles, and neurodegeneration of these regions will extensively be evaluated. Developing automated methods to improve the aforementioned research areas would enable specialists to determine the progression of the disease and find the link between the biomarkers and more accurate detection of Alzheimer’s disease onset. 展开更多
关键词 deep learning image processing linear mixed effect model NEUROIMAGING neuroimaging data sources onset of Alzheimer’s disease detection pattern recognition
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Controls of accommodation to sediment-supply ratio on sedimentary architecture of continental fluvial successions 被引量:1
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作者 Wei Li Da-Li Yue +6 位作者 Yu-Shan Du Jian Li Chi Zhang Zhi-Qiang Gong Xue-Ting Zhang Qing-Lin Shu Jian Gao 《Petroleum Science》 SCIE EI CAS CSCD 2023年第4期1961-1977,共17页
The applicability of sequence stratigraphic models to continental fluvial successions has long been topic for debate. To improve our understanding of how fluvial architectures record responses to changes in the ratio ... The applicability of sequence stratigraphic models to continental fluvial successions has long been topic for debate. To improve our understanding of how fluvial architectures record responses to changes in the ratio between accommodation rate and sediment-supply rate (A/S), two case studies are analyzed, including a densely drilled subsurface fluvial reservoir imaged with a seismic cube, and an outcropping fluvial succession. The subsurface dataset provides a larger, three-dimensional perspective, whereas the outcrop dataset enables observation at higher resolution. On the basis of both datasets, channel-body density, channel-body stacking patterns and their formative river types are interpreted at different scales, and how these may reflect responses to A/S change (the rate of accommodation creation relative to the rate of sediment supply) are discussed. The results indicate that (i) channel-body stacking patterns undergo four evolutionary stages along with the A/S increase, i.e., multi-story, mixed multi- and two-story, two-story, and isolated patterns;(ii) channel-body density decreases along with the channel-body stacking patterns varying from multi-story to isolated;(iii) formative rivers types are interpreted as evolving from braided planforms to braided-meandering planforms and then to meandering ones, with the increase of A/S. 展开更多
关键词 Channel body sedimentary architecture stacking pattern Formative river type sequence stratigraphy A/s
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