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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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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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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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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 城市空间格局 湖北省 演变 连接网络 灯光 城市节点 夜间光照 指数模型
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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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Visualization of flatness pattern recognition based on T-S cloud inference network 被引量:1
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作者 张秀玲 赵亮 +1 位作者 臧佳音 樊红敏 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第2期560-566,共7页
Flatness pattern recognition is the key of the flatness control. The accuracy of the present flatness pattern recognition is limited and the shape defects cannot be reflected intuitively. In order to improve it, a nov... Flatness pattern recognition is the key of the flatness control. The accuracy of the present flatness pattern recognition is limited and the shape defects cannot be reflected intuitively. In order to improve it, a novel method via T-S cloud inference network optimized by genetic algorithm(GA) is proposed. T-S cloud inference network is constructed with T-S fuzzy neural network and the cloud model. So, the rapid of fuzzy logic and the uncertainty of cloud model for processing data are both taken into account. What's more, GA possesses good parallel design structure and global optimization characteristics. Compared with the simulation recognition results of traditional BP Algorithm, GA is more accurate and effective. Moreover, virtual reality technology is introduced into the field of shape control by Lab VIEW, MATLAB mixed programming. And virtual flatness pattern recognition interface is designed.Therefore, the data of engineering analysis and the actual model are combined with each other, and the shape defects could be seen more lively and intuitively. 展开更多
关键词 模式识别 板形控制 推理网络 Ts 可视化 虚拟现实技术 模糊神经网络 MATLAB
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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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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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TPFTZ(Tianjin Port Free Trade Zone)——A New Pattern of China's Openning to the Outside World
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作者 Zhu Qinyuan: Director of Administrative Committe of the TPFTZ Shen Huan 《南开经济研究》 CSSCI 北大核心 1994年第S1期35-39,20,共6页
Under the guidance of Deng Xiao-ping’s strategic think-ing of openning to the outside world, the structure of om-nibearing openness has basically taken shape in China. Follow-
关键词 Free TPFTZ Tianjin Port Free Trade Zone A New pattern of China’s Openning to the Outside World
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基于T-S模糊神经网络的飞行学员飞行技能评价模型构建研究
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作者 李根 汪海波 +2 位作者 司海青 潘亭 刘海波 《载人航天》 CSCD 北大核心 2023年第5期616-623,共8页
为准确评价飞行学员飞行技能的优劣,在分析飞行学员起落航线各飞行阶段任务的基础上,参照飞行训练手册并结合与教员的访谈,建立了飞行学员飞行技能评价指标体系。运用T-S模糊神经网络搭建的飞行技能评价模型实现对飞行学员飞行技能评价... 为准确评价飞行学员飞行技能的优劣,在分析飞行学员起落航线各飞行阶段任务的基础上,参照飞行训练手册并结合与教员的访谈,建立了飞行学员飞行技能评价指标体系。运用T-S模糊神经网络搭建的飞行技能评价模型实现对飞行学员飞行技能评价,采集118名飞行学员飞行数据(有效数据110组),80组数据用于训练模型,30组数据用于测试,以验证模型评价的适用性和精确度。结果表明:T-S模糊神经网络具有很好的学习效率,评价飞行学员飞行技能准确度为976%,该方法构建出的评价模型应用于飞行学员飞行技能评价有效可行。 展开更多
关键词 T-s模糊神经网络 起落航线 飞行数据 飞行技能评价
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100例后天因素所致儿童OSAHS变应原检测结果分析
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作者 金莹玉 韩泽利 《锦州医科大学学报》 CAS 2023年第5期80-84,共5页
目的 通过统计解放军总医院第四医学中心耳鼻咽喉头颈外科病区收治后天因素所致儿童阻塞性睡眠呼吸暂停低通气综合症(obstructive sleep apnea hypopnea syndrome, OSAHS)变应原及IgE检测结果,探究OSAHS儿童过敏情况。方法 选取2021年2... 目的 通过统计解放军总医院第四医学中心耳鼻咽喉头颈外科病区收治后天因素所致儿童阻塞性睡眠呼吸暂停低通气综合症(obstructive sleep apnea hypopnea syndrome, OSAHS)变应原及IgE检测结果,探究OSAHS儿童过敏情况。方法 选取2021年2月至2021年11月在解放军总医院第四医学中心耳鼻咽喉头颈外科因扁桃体伴腺样体肥大导致3~12岁儿童OSAHS而行扁桃体伴腺样体切除手术的100例完整临床资料。采用免疫印迹法,共检测吸入性变应原10种,食入性变应原9种,血清总IgE 1组。分析OSAHS儿童变应原和过敏情况。结果 吸入性变应原阳性率最高的种类依次为:真菌、猫毛、屋尘、夏秋花粉、户尘螨、早晚春花粉。食入性变应原阳性率种类依次为:牛奶、腰果、鸡蛋白、苋及虾。过敏原种类阳性1项有37人次,同时合并2项有20人次,同时合并3项及以上有11人次,总过敏原阳性人数为68人次,总阳性率为68%。吸入性及食入性过敏原阳性率由高到低前六位种类依次为:牛奶、猫毛皮屑、真菌、腰果、夏秋花粉组、屋尘。不同年龄组及不同睡眠呼吸暂停阻塞程度患儿其变应原阳性率统计中3~6岁年龄组儿童过敏源阳性率最高,其次为6~9岁年龄组,9~12岁年龄组阳性率最低。不同睡眠呼吸暂停阻塞程度患儿过敏原阳性率与其阻塞程度呈正相关。结论 后天因素导致的儿童OSAHS与过敏原刺激相关,且患儿发病年龄越小,过敏易感程度越高,3~6岁年龄组儿童过敏源阳性率最高,儿童OSAHS睡眠呼吸阻塞程度与过敏仍需进一步大样本统计分析。 展开更多
关键词 儿童OsAHs 变应原 IGE 患病规律
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基于男性腰臀裆部NURBS曲面模型的内裤数字化制版 被引量:1
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作者 任泽 钟安华 《纺织学报》 EI CAS CSCD 北大核心 2023年第8期167-173,共7页
为解决男士内裤版型因前裆凸起量规定模糊而导致内裤裆部不合体的问题,对男性人体建立腰臀裆部曲面仿真模型,依据曲面模型生成合体的数字化内裤版型。运用三维人体扫描仪获取实验对象腰臀裆部点云数据,使用逆向工程软件提取点云数据中... 为解决男士内裤版型因前裆凸起量规定模糊而导致内裤裆部不合体的问题,对男性人体建立腰臀裆部曲面仿真模型,依据曲面模型生成合体的数字化内裤版型。运用三维人体扫描仪获取实验对象腰臀裆部点云数据,使用逆向工程软件提取点云数据中能表征腰臀裆部形态的点云坐标集,按照NURBS曲线曲面原理在Solidworks软件中建立腰臀裆部曲面模型并对7块曲面进行展平,以ET服装CAD软件为版片编辑平台生成合体的男士内裤版型。结果表明:从点云数据中提取7个特征截面的点云坐标集构建的曲面模型能够表征腰臀裆部体表形态,数字化男士内裤版型在虚拟试衣和真实试穿中十分贴合男性腰臀裆部形态,内裤服装压强范围在0~2.4 kPa之间,可满足人体舒适性要求,验证显示采用腰臀裆部曲面模型生成数字化内裤版型是合理的,数字化内裤版型更符合人体腰臀裆部形态特征,为合体和贴体服装版型的快速获取提供一种新的方法。 展开更多
关键词 数字化服装制版 男士内裤版型 腰臀裆部曲面模型 NURBs曲面 曲面展平
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