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西藏定日2025年1月M_(S)6.8级强震对藏式民居的破坏模拟与动力响应反演
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作者 常鸣 范宣梅 +2 位作者 周康驰 赵伟华 刘洋 《成都理工大学学报(自然科学版)》 北大核心 2025年第2期185-198,共14页
为研究西藏自治区日喀则市定日县藏式民居在M_(S)6.8级地震中的破坏模式与动力响应,以土木石结构的藏式民居为原型,使用1/12缩小模型开展了地震模拟振动台试验。对西藏定日藏式民居在M_(S)6.8级地震中破坏情况和动力响应反演的重要研究... 为研究西藏自治区日喀则市定日县藏式民居在M_(S)6.8级地震中的破坏模式与动力响应,以土木石结构的藏式民居为原型,使用1/12缩小模型开展了地震模拟振动台试验。对西藏定日藏式民居在M_(S)6.8级地震中破坏情况和动力响应反演的重要研究结果如下:(1)藏式民居模型的薄弱点集中在屋檐处的墙体、二层、门窗开口附近的墙体以及墙角,其中屋檐和门窗开口是最易受损的部位。(2)模型结构存在扭转效应,即模型第一层刚度远超过第二层,导致第二层产生了显著的层间位移并伴随扭转效应,使得该层成为结构的薄弱层。(3)通过加载逐级增大的加速度,模型能有效抵御高达0.4g的地震强度,但在更高强度的地震(0.62g及以上)作用下,模型会出现倒塌破坏。由于缩尺效应,实际房屋的破坏程度将更为严重。本研究对认识此次定日M_(S)6.8级地震房屋破坏模式提供科学依据,同时也为该地区藏式房屋抗震性能的提高以及灾后重建提供重要参考。 展开更多
关键词 藏式民居 地震模拟振动台试验 破坏模式 动力响应 定日M_(s)6.8级地震
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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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基于改进D-S证据理论与深度学习的矿用电缆缺陷识别研究
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作者 孟强 舒珊 +3 位作者 秦晓梅 郭振振 孔宁宁 刘瑞国 《中国煤炭》 北大核心 2025年第1期181-188,共8页
准确识别局部放电缺陷模式在矿用电缆的缺陷评估中至关重要,煤矿供电环境复杂,矿用电缆缺陷识别也尤为重要。因此提出了一种融合改进D-S证据理论与深度学习的方法,构建基于Efficientnet-b0和Resnet-18的深度学习识别模型用于提取矿用高... 准确识别局部放电缺陷模式在矿用电缆的缺陷评估中至关重要,煤矿供电环境复杂,矿用电缆缺陷识别也尤为重要。因此提出了一种融合改进D-S证据理论与深度学习的方法,构建基于Efficientnet-b0和Resnet-18的深度学习识别模型用于提取矿用高压电缆局部放电信号的关键特征并进行初步分类,引入D-S证据理论对单一模型的识别结果进行融合。针对证据冲突的情况,引入基尼不纯度改进D-S理论中的权重分配,从而提高矿用电缆缺陷识别的准确率。现场试验表明,融合后的模型平均识别率为94.2%,双模型融合的各项性能均比单一模型有所提高,有效提高了矿用电缆缺陷识别的准确度,为煤矿配电网安全可靠运行提供保障。 展开更多
关键词 矿用电缆 局部放电 D-s证据理论 深度学习 模式识别 双模型融合
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基于Logistic回归模型评估肌电图震颤指标对帕金森病的诊断价值
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作者 周曾 徐竞 +5 位作者 凤兆海 郑颖炜 崔敏 王宗玉 方芳 李美英 《实用临床医药杂志》 2025年第1期33-38,共6页
目的 基于Logistic回归模型探讨肌电图震颤指标对帕金森病(PD)的诊断价值。方法 选取65例PD患者(PD组)和39例特发性震颤(ET)患者(ET组)作为研究对象,均接受肌电图震颤分析,比较2组患者的一般资料、疾病相关资料和肌电图震颤特点。采用... 目的 基于Logistic回归模型探讨肌电图震颤指标对帕金森病(PD)的诊断价值。方法 选取65例PD患者(PD组)和39例特发性震颤(ET)患者(ET组)作为研究对象,均接受肌电图震颤分析,比较2组患者的一般资料、疾病相关资料和肌电图震颤特点。采用多因素Logistic回归分析法筛选PD的独立影响因素,并绘制受试者工作特征(ROC)曲线,通过曲线下面积(AUC)评估肌电图震颤指标对PD的诊断价值。结果 与ET组比较,PD组单侧肢体起病者和震颤波谱的波频数≥2个者占比更高,有震颤家族史者占比更低,差异有统计学意义(P<0.05);PD组静息状态、姿势状态及负重状态(负重1 000 g)的震颤峰频率均低于ET组,差异有统计学意义(P<0.05);2组静息状态、负重状态的震颤节律形式差异有统计学意义(P<0.05), PD组以交替收缩模式为主,ET组以同步收缩模式为主。多因素Logistic回归分析结果显示,负重状态震颤峰频率、静息状态震颤节律形式、震颤波谱的波频数均为PD的独立影响因素(P<0.05)。ROC曲线显示,负重状态震颤峰频率、静息状态震颤节律形式、震颤波谱的波频数诊断PD的AUC分别为0.886、0.750、0.779,且三者联合诊断PD的AUC最大(0.936),敏感度、特异度分别为81.54%、94.87%。结论 肌电图震颤分析提供的负重状态震颤峰频率、静息状态震颤节律形式及震颤波谱的波频数可作为早期诊断PD的临床指标,且三者联用的诊断价值更高,可用于鉴别诊断PD和ET。 展开更多
关键词 LOGIsTIC回归模型 帕金森病 特发性震颤 肌电图 震颤峰频率 震颤节律形式
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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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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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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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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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Quantum Algorithm for Mining Frequent Patterns for Association Rule Mining 被引量:1
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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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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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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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On the origin of cardiac mucosa: A histological and immunohistoc-hemical study of cytokeratin expression patterns in the developing esophagogastric junction region and stomach
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作者 Gert De Hertogh Peter Van Eyken +1 位作者 Nadine Ectors Karel Geboes 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第29期4490-4496,共7页
AIM: To examine the fetal and neonatal esophagogastric junction region (EGJ) histologically for the presence of an equivalent to adult cardiac mucosa (CM); to study the expression patterns of all cytokeratins (C... AIM: To examine the fetal and neonatal esophagogastric junction region (EGJ) histologically for the presence of an equivalent to adult cardiac mucosa (CM); to study the expression patterns of all cytokeratins (CK) relevant to the EGJ during gestation; to compare the CK profile of the gestational and the adult EGJ; and to determine the degree of development in the adult EGJ histology and CK profile during gestation. METHODS: Forty-eight fetal autopsy specimens of the EGJ were step-sectioned and stained with hematoxylin and eosin (H&E) to select sections showing the mucosal lining. Immunohistochemistry for CK5, 7, 8, 13, 18, 19, and 20 was performed. Antibody staining was then graded for location, intensity, and degree. RESULTS: The distal esophagus was lined by simple columnar epithelium from 12-wk gestational age (GA). The proximal part of this segment consisted of mucusproducing epithelium, devoid of parietal cells. CK5 and 13 were present exclusively in multilayered epithelia and CK8, 18, and 19 predominantly in simple columnar epithelium. There were no differences in the frequencies of the coordinate CK7+/20+ and the CK7-/20- immunophenotypes between different locations. The prevalence of the CK7+/ 20- immunophenotype decreased, and that of the CK7-/ 20+ immunophenotype increased significantly from the distal esophagus to the distal stomach. CONCLUSION: Fetal columnar-lined lower esophagus (fetal CLE) may be the equivalent and precursor of the short segments of columnar epithelium found in the distal esophagus of some normal adult subjects. Esophageal simple columnar epithelium without parietal cells (ESN) may be the precursor of adult CM. The similarities between the fetal and adult EGJ and stomach CK expression pattems support the conclusion that adult CN has an identifiable precursor in the fetus. This would then indicate that at least a part of the adult CM has a congenital origin. 展开更多
关键词 Cardiac mucosa ORIGIN Fetal autopsy Barrett's CK7/20 pattern
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Patterns of international governance in the Arctic and China's approach
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作者 ZHAO Long 《Advances in Polar Science》 2016年第3期170-179,共10页
The process of rapid change in the Arctic is creating both opportunities and challenges. This paper highlights interactions between different actors in the Arctic in response to multidimensional environmental, politic... The process of rapid change in the Arctic is creating both opportunities and challenges. This paper highlights interactions between different actors in the Arctic in response to multidimensional environmental, political, commercial, and human challenges. It shows that international governance in the Arctic can be characterized by global, multilateral, and regional patterns derived from different mechanisms such as the Arctic Council or the Ilulissat declaration platform, and these interactions are based on common acknowledgment of challenges, mutual interests, and coordinated actions. The paper also examines China's participation in international governance in the Arctic. Distinguish from non-Arctic states in a general sense, China as an important stakeholder has both the rights and the capacity to be engaged in multilevel governance patterns. The substantive contribution of China's participation--an explorer in scientific cooperation, a pioneer promoting environmental protection, a potential consumer and investor in relation to economic opportunities, and a promoter of local development^are deeply interdepended with the future of development of three ~overnance patterns relatin~ to international ~overnance in the Arctic. 展开更多
关键词 ARCTIC governance patterns China's approach
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Novel similarity measures for face representation based on local binary pattern
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作者 祝世虎 封举富 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第2期223-226,共4页
The successful face recognition based on local binary pattern(LBP)relies on the effective extraction of LBP features and the inferring of similarity between the extracted features.In this paper,we focus on the latter ... The successful face recognition based on local binary pattern(LBP)relies on the effective extraction of LBP features and the inferring of similarity between the extracted features.In this paper,we focus on the latter and propose two novel similarity measures for the local matching methods and the holistic matching methods respectively.One is Earth Mover's Distance with Hamming and Lp ground distance(EMD-HammingLp),which is a cross-bin dissimilarity measure for LBP histograms.The other is IMage Hamming Distance(IMHD),which is a dissimilarity measure for the whole LBP images.Experiments on FERET database show that the proposed two similarity measures outperform the state-of-the-art Chi-square similarity measure for extraction of LBP features. 展开更多
关键词 similarity measurement local binary pattern Earth Mover's Distance IMage Euclidean Distance
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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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Impact of t:ybercrime in Japan-Findings of (:ybercrime Victimization Survey
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作者 Taisuke Kanayama 《Sociology Study》 2017年第6期331-340,共10页
Although the threat of cybercrime is said to expand year by year recently, an actual impact of the threat has not estimated in Japan due to several reasons including inadequate statistics of cybercrime. The purpose of... Although the threat of cybercrime is said to expand year by year recently, an actual impact of the threat has not estimated in Japan due to several reasons including inadequate statistics of cybercrime. The purpose of this study is to estimate the volume of cybercrime in Japan and identify its characteristics based on the result of cybercrime victimization survey conducted by the study group for cybercrime of Nihon University (NU) in 2016. The study group obtained a cybercrime victimization rate of 5.36% and concluded that cybercrime victimization in Japan is quite serious comparing with other survey results and crime statistics. Furthermore, the study group explored how to figure out cybercrime victimization more precisely based on characteristics of cybercrime obtained by this survey and proposed a couple of appropriate measures to cope with cybercrime. 展开更多
关键词 CYBERCRIME victimization survey victim's report
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Modeling and Mapping of Urban Sprawl Pattern in Cairo Using Multi-Temporal Landsat Images, and Shannon’s Entropy
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作者 Hala A. Effat Mohamed A. El Shobaky 《Advances in Remote Sensing》 2015年第4期303-318,共16页
Cairo city, being the Egypt’s industrial and cultural center, has a problem of rapid urban sprawl. The city has an extremely high population density which is continuously increasing through informal settlements that ... Cairo city, being the Egypt’s industrial and cultural center, has a problem of rapid urban sprawl. The city has an extremely high population density which is continuously increasing through informal settlements that grow by sprawling due to migration from the Nile Delta villages and the high population growth rates. The present study attempts to understand, detect and quantify the spatial pattern of Cairo’s urban sprawl using Shannon’s entropy and multi-temporal Landsat TM and ETM images acquired for the period from 1984 to 2013. Supervised classification was applied to extract the built-up areas and to measure the changes in the urban land-use class among the city wards. Shannon’s entropy was applied to model the city’s urban sprawl, trend and spatial change. The entropy values for the city’s electoral wards were modeled and used in an interpolation function to create an entropy surface (index) for each acquired temporal image. Such index indicates the spatial pattern of the urban sprawl and provides a visual comparison of the entropy phenomenon in such wards. Results indicate that Shannon’s entropy index increased from (1.4615) in year 1984 to (2.1023) in year 2013, indicating more dispersed urban growth, a sign of urban sprawl. The maximum entropy values are found in the eastern wards namely El Nozha, Awal Nasr District, Thany Nasr-District, El Salam, El Marg and El Bassatein. A regression analysis was carried for the population growth rate and the built-up areas. Findings help in understanding the sprawl patterns and dynamics among Cairo’s electoral wards and provide a visual comparison. The applied methodology provides explanations and facilitates tracing and measuring the urban sprawl which is needed by decision makers and city planners of mega cities. 展开更多
关键词 shannon’s ENTROPY Urban Growth sPRAWL patterns LANDsAT CAIRO EGYPT
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