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聚焦儿童早期数学模式能力的发展——国际儿童模式能力评估与干预研究述评 预览
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作者 田方 黄瑾 《外国中小学教育》 CSSCI 北大核心 2019年第3期32-46,共15页
模式(Pattern)能力是儿童早期数学能力的重要组成部分,对儿童数学思维和代数能力的发展具有重要作用。已有研究表明儿童早期模式能力的发展对其日后的数学学习具有重要影响,要深入研究儿童早期模式能力发展和认知机制及其与其它相关认... 模式(Pattern)能力是儿童早期数学能力的重要组成部分,对儿童数学思维和代数能力的发展具有重要作用。已有研究表明儿童早期模式能力的发展对其日后的数学学习具有重要影响,要深入研究儿童早期模式能力发展和认知机制及其与其它相关认知能力之间的关系,这些都有赖于科学化和系统化的模式评估工具。本文梳理和分析了美国和澳大利亚的5种模式评估工具及其相关的干预研究,在此基础上为编制适宜我国儿童的模式评估工具提供有效依据,以期在模式评估工具的目的、任务设置、表征形式及信效度等方面提出借鉴。 展开更多
关键词 模式 重复性模式 发展性模式 评估任务 干预
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Patterning Defect Study for Process Integration Engineering Using Pattern Fidelity Monitoring with Review SEM Images 预览
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作者 Yu Zhang Abhishek Vikram +9 位作者 Ming Tian Tianpeng Guan Jianghua Leng Baojun Zhao Lei Yan Wei Hu Guojie Chen Hui Wang Gary Zhang Wenkui Liao 《微电子制造学报》 2019年第2期21-25,共5页
Normally the optical wafer inspection tools are used for advanced process control in high volume manufacturing of semiconductor devices. The SEM Review is done for limited sample of inspection defects to do defect bas... Normally the optical wafer inspection tools are used for advanced process control in high volume manufacturing of semiconductor devices. The SEM Review is done for limited sample of inspection defects to do defect based process characterization. The defect classes that are monitored normally indicate process and random defect issues. There is limited to no information of patterning related issues in real time defect monitor. Moreover, with the objective of process integration engineering of multiple processes it becomes harder to see the evolution of a defect in the line. The Die-to-Database Pattern Monitor (D2DB-PM) solution has addressed this problem. It uses the existing high resolution images from the Review and Metrology tools and compares the pattern shapes with the design reference. This way it captures patterning deviations in real time. Here we report the subtle defect problem encountered in process integration and the results from using the D2DB-PM solution. We found that this approach reduces the workload on CDSEM tools by analyzing SEM Review images instead and the automated reports improves the efficiency of all process teams. 展开更多
关键词 Die-to-database PATTERN MONITOR AFTER Develop INSPECTION (ADI) AFTER Etch INSPECTION (AEI) SEM REVIEW CDSEM PATTERN centric PATTERN MONITOR
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Texture Feature Extraction from Thyroid MR Imaging Using High-Order Derived Mean CLBP
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作者 Zhe Liu Cheng-Jian Qiu +3 位作者 Yu-Qing Song Xiao-Hong Liu Juan Wang Victor S.Sheng 《计算机科学技术学报:英文版》 SCIE EI CSCD 2019年第1期35-46,共12页
In the field of medical imaging,the traditional local binary pattern (LBP)and its improved algorithms are often sensitive to noise.Traditional LBPs are solely based on the signal information from local differences,and... In the field of medical imaging,the traditional local binary pattern (LBP)and its improved algorithms are often sensitive to noise.Traditional LBPs are solely based on the signal information from local differences,and the binary quantization method oversimplifies the local texture features while disregarding the imaging information from the concaveconvex regions between the high-order pixels and the neighboring sampling points.Therefore,we propose an improved Derived Mean Complete Local Binary Pattern (DM_CLBP) algorithm based on high-order derivatives.In the DM_CLBP method,the grey value of a single pixel is replaced by the mean grey value of the rectangular area block,and the difference between pixel values in the area is obtained using the second-order differentiation method.Based on the calculation concept of the complete local binary pattern (CLBP)algorithm,the cascade signs and magnitudes of the two components are encoded and recombined in DM_CLBP using a uniform pattern.The results from the experiments showed that the proposed DM_CLBP descriptors achieved a classification accuracy of 94.4%.Compared with LBP and other improved algorithms,the DM_CLBP algorithm presented in this study can effectively differentiate between lesion areas and normal areas in thyroid MR,(magnetic resonance)images and shows the improved accuracy of area classification. 展开更多
关键词 THYROID magnetic resonance imaging (MRI) LOCAL BINARY PATTERN texture feature complete LOCAL BINARY PATTERN (CLBP)
谈清代景泰蓝纹样的种类与文化涵义
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作者 安丽哲 《创意设计源》 2019年第3期4-8,共5页
目前学界对于传统纹样的探讨主要集中于瓷器纹样、服饰刺绣、石刻、木刻、剪纸等类别上,鲜有对景泰蓝的传统纹样进行总结和讨论。笔者在搜集国内外大量清代景泰蓝纹样的基础上,结合历史文献将其中最常见的传统纹样的种类与涵义进行概括... 目前学界对于传统纹样的探讨主要集中于瓷器纹样、服饰刺绣、石刻、木刻、剪纸等类别上,鲜有对景泰蓝的传统纹样进行总结和讨论。笔者在搜集国内外大量清代景泰蓝纹样的基础上,结合历史文献将其中最常见的传统纹样的种类与涵义进行概括与分析,从而为传统景泰蓝文化的传承与发展提供参考。 展开更多
关键词 景泰蓝 纹样 龙纹 手工艺 艺术人类学
Human colorectal cancer cells frequently express IgG and display unique Ig repertoire 预览
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作者 Zi-Han Geng Chun-Xiang Ye +6 位作者 Yan Huang Hong-Peng Jiang Ying-Jiang Ye Shan Wang Yuan Zhou Zhan-Long Shen Xiao-Yan Qiu 《世界胃肠肿瘤学杂志:英文版(电子版)》 CAS 2019年第3期195-207,共13页
BACKGROUND There is growing evidence proving that many human carcinomas, including colon cancer, can overexpress immunoglobulin(Ig);the non B cancer cell-derived Ig usually displayed unique V(D)J rearrangement pattern... BACKGROUND There is growing evidence proving that many human carcinomas, including colon cancer, can overexpress immunoglobulin(Ig);the non B cancer cell-derived Ig usually displayed unique V(D)J rearrangement pattern that are distinct from B cell-derived Ig. Especially, the cancer-derived Ig plays important roles in cancer initiation, progression, and metastasis. However, it still remains unclear if the colon cancer-derived Ig can display unique V(D)J pattern and sequencing, which can be used as novel target for colon cancer therapy.AIM To investigate the Ig repertoire features expressed in human colon cancer cells.METHODS Seven cancerous tissue samples of colon adenocarcinoma and corresponding noncancerous tissue samples were sorted by fluorescence-activated cell sorting using epithelial cell adhesion molecule as a marker for epithelial cells. Ig repertoire sequencing was used to analyze the expression profiles of all 5 classes of Ig heavy chains(IgH) and the Ig repertoire in colon cancer cells and corresponding normal epithelial cells.RESULTS We found that all 5 IgH classes can be expressed in both colon cancer cells and normal epithelial cells. Surprisingly, unlike the normal colonic epithelial cells that expressed 5 Ig classes, our results suggested that cancer cells most prominently express IgG. Next, we found that the usage of Ig in cancer cells caused the expression of some unique Ig repertoires compared to normal cells. Some VH segments, such as VH3-7, have been used in cancer cells, and VH3-74 was frequently present in normal epithelial cells. Moreover, compared to the normal cell-derived Ig, most cancer cell-derived Ig showed unique VHDJH patterns.Importantly, even if the same VHDJH pattern was seen in cancer cells and normal cells, cancer cell-derived IgH always displayed distinct hypermutation hot points.CONCLUSION We found that colon cancer cells could frequently express IgG and unique IgH repertoires, which may be involved in carcinogenesis of colon cancer. The unique IgH repertoire has the potenti 展开更多
关键词 IMMUNOGLOBULIN REPERTOIRE SEQUENCING COLORECTAL cancer VDJ PATTERN VJ PATTERN
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网格曲面上自由形状特征交互式阵列设计 预览
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作者 胡俊 刘斌 +1 位作者 黄常标 江开勇 《计算机集成制造系统》 EI CSCD 北大核心 2019年第1期61-70,共10页
为了提高设计效率、便于后续布局设计优化,提出一种流形网格曲面上自由形状特征可参数驱动的阵列重用设计方法,引入场向参数化方法获得网格曲面上的等值分布线,再由两组不同角度的等值分布线的交点确定特征的阵列位置;以阵列位置点的法... 为了提高设计效率、便于后续布局设计优化,提出一种流形网格曲面上自由形状特征可参数驱动的阵列重用设计方法,引入场向参数化方法获得网格曲面上的等值分布线,再由两组不同角度的等值分布线的交点确定特征的阵列位置;以阵列位置点的法矢和方向矢量构建局部坐标标架,用以确定阵列特征的朝向,并交互式确定各特征大小;最后采用基于旋转不变量的拉普拉斯网格变形方法,使得各阵列特征和目标曲面自然过渡,实现自由形状特征的有序多重复制。将位置阵列和特征变形分开处理,使得阵列特征的变形不依赖于场向参数化,仅与其所在的局部区域有关而与曲面整体无关,既保证了各特征和目标网格的融合效果,也为实施并行计算、降低时间成本提供了条件。试验结果表明,所介绍方法可行、有效,能满足自由形状特征在曲面上的阵列式交互设计要求。 展开更多
关键词 场向参数化 阵列 重用 网格曲面 自由形状特征 交互设计
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Harnessing structural instability for cell durotaxis 预览
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作者 Jie Wei Xiaofeng Chen Bin Chen 《力学学报:英文版》 SCIE EI CAS CSCD 2019年第2期355-364,共10页
Cells were suggested to sense matrix rigidity by applying fluctuating forces, but the underlying mechanism remains elusive. Here with a generic filament-crosslinker modeling system for stress fibers, we demonstrate th... Cells were suggested to sense matrix rigidity by applying fluctuating forces, but the underlying mechanism remains elusive. Here with a generic filament-crosslinker modeling system for stress fibers, we demonstrate that high mechanical forces can be induced by specific protein-protein interactions with biased kinetics. Strikingly, we further find that there exist two patterns of force generation, a stable pattern and a fluctuated pattern, in agreement with previous experimental observations. Our analysis indicates that the fluctuated force profile is essentially due to force-induced structural instability during structural assembly. We suggest that how cells utilize or circumvent such stable forces or fluctuated forces may be important in other biological processes as well, though whether such forces should be regarded as passive or active is still tentative. 展开更多
关键词 PROTEIN-PROTEIN interaction Biased KINETICS FORCE GENERATION STABLE PATTERN Fluctuated PATTERN
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徽州传统民居门罩的装饰呈现与审美内涵 预览
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作者 江保锋 闻婧 《西安建筑科技大学学报:社会科学版》 2019年第2期4-10,共7页
徽州传统民居中所遗留明清时期的门罩形制以造型朴素的门楣式、装饰舒展的垂花式和结构复杂的牌坊式为主要代表,以砖石雕刻为主要装饰载体,加之考究的尺度和精美的图式,展现了徽州传统民居独特的装饰风格。门罩的装饰在艺术呈现与审美... 徽州传统民居中所遗留明清时期的门罩形制以造型朴素的门楣式、装饰舒展的垂花式和结构复杂的牌坊式为主要代表,以砖石雕刻为主要装饰载体,加之考究的尺度和精美的图式,展现了徽州传统民居独特的装饰风格。门罩的装饰在艺术呈现与审美内蕴方面彰显着题材寓意吉祥、形象淳厚儒雅、视觉饱满丰厚、工艺精巧繁缛、审美积淀朴厚等艺术特征,门罩装饰图式所承载徽州人的精神生活、民俗文化和民俗内涵是中国建筑文化、民俗文化和审美文化的重要部分,蕴含着厚重的现实价值与时代意义。 展开更多
关键词 徽州 门罩 形制 尺度 图式 审美内涵
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Spatiotemporal Evolution of Waterlogging Events in Eastern China from 1961 to 2016 预览
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作者 KONG Feng 《景观研究:英文版》 2019年第4期64-72,77共10页
In this study, based on the data on the frequency of waterlogging events and the number of waterlogging days of 1,638 stations from 1961 to 2016, a variety of mathematical statistics methods were used to analyze the s... In this study, based on the data on the frequency of waterlogging events and the number of waterlogging days of 1,638 stations from 1961 to 2016, a variety of mathematical statistics methods were used to analyze the spatiotemporal evolution of waterlogging events in eastern China. The results showed that:① In terms of time, the annual frequency of waterlogging events and the number of waterlogging days in eastern China in 1961–2016 showed an increasing trend despite of fluctuations. In the interdecadal changes, the highest frequency of waterlogging events and the greatest number of waterlogging days occurred in the 1990s, and from the 1960s to the 1980s, the frequency of waterlogging events and the number of waterlogging days in eastern China showed a decreasing trend. There were 6-year and 30-year periodic variations in the frequency of waterlogging events and the number of waterlogging days in eastern China, and mutations occurred in 1991.② In terms of space, from 1961 to 2016, the areas with high frequency of waterlogging events in various years in eastern China were mainly South China, western and southern Yunnan, northern Jiangsu, southern Zhejiang, northern Fujian, junction areas between Hunan and Chongqing, northern Sichuan, and eastern Liaoning.③ In the spatial distribution of change trends and fluctuation characteristics, the frequency of waterlogging events and the number of waterlogging days in eastern China increased significantly in the southeastern coastal areas from 1961 to 2016, and the fluctuations of the frequency of waterlogging events and the number of waterlogging days in eastern China from 1961 to 2016 presented a spatial variation pattern of low in the southwest and high in the northwest. 展开更多
关键词 WATERLOGGING EVENT SPATIOTEMPORAL pattern MANN-KENDALL (MK) test ENSEMBLE empirical mode decomposition (EEMD) WAVELET analysis Climate change
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基于STDP学习规则的视网膜神经回路的特性 预览
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作者 杨师华 刘深泉 +1 位作者 詹飞彪 张晓函 《动力学与控制学报》 2019年第2期127-135,共9页
基于视网膜的生理解剖结构,构建了包括视锥细胞、水平细胞、双极细胞、AII无长突细胞、神经节细胞、外侧膝状体核和ON通路与OFF通路的视网膜神经回路模型,并在神经节细胞层和外侧膝状体核层的突触连接中引入STDP(Spike-Timing Dependent... 基于视网膜的生理解剖结构,构建了包括视锥细胞、水平细胞、双极细胞、AII无长突细胞、神经节细胞、外侧膝状体核和ON通路与OFF通路的视网膜神经回路模型,并在神经节细胞层和外侧膝状体核层的突触连接中引入STDP(Spike-Timing Dependent Plasticity)学习规则,通过添加单一图形刺激和交替图形刺激,比较神经节细胞和外侧膝状体核的电位发放、发放频率以及两者之间突触权重的变化,研究视网膜神经回路的信息传递特性.结果表明:构建的神经回路模型可有效地将光照强度信息转化为发放时序频率信息,且表现出生物视网膜的信息结构特性;STDP学习规则的引入使得外侧膝状体核层接收了相应的刺激模式并学习记忆了这种模式,且ON通路和OFF通路表现出学习独立性;STDP学习规则可以对交替出现的图形刺激,在突触权重的空间分布上进行叠加,且重叠部分的学习效果更加显著. 展开更多
关键词 视网膜 突触 STDP学习规则 神经回路 发放序列 模式
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美国科学课程发展的新趋向--基于共通概念的科学课程构建
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作者 高潇怡 孙慧芳 《比较教育研究》 CSSCI 北大核心 2019年第1期53-60,共8页
共通概念是当前国际科学教育研究中受到高度关注的内容。传统的科学课程主要以学科领域作为组织科学内容的出发点,当前科学课程发展的重要趋势之一表现为共通概念在科学课程中居于核心地位。共通概念的发展经历了从作为课程建构理念到... 共通概念是当前国际科学教育研究中受到高度关注的内容。传统的科学课程主要以学科领域作为组织科学内容的出发点,当前科学课程发展的重要趋势之一表现为共通概念在科学课程中居于核心地位。共通概念的发展经历了从作为课程建构理念到以重要内容在课程中呈现进而统领科学课程内容的变化历程。美国当前基于共通概念架构科学内容的课程框架既体现了共通概念作为核心要素与其他内容维度之间的密切关系,也表现为共通概念具体内容的细化以及在不同年级之间的进阶要求。美国基于共通概念建构科学课程的发展对我国科学课程建设与发展具有重要借鉴价值。 展开更多
关键词 美国 共通概念 科学课程
运动员临场应对能力的结构模式构建及检验 预览
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作者 孙卓 于永平 董德龙 《体育科技文献通报》 2019年第3期29-32,共4页
研究通过对200名运动员进行问卷调查,在对《运动员临场应对能力测评工具》进行修正的基础上,进一步对运动员临场应对能力的内部结构模式进行了构建与检验。结果显示:(1)由于量表中T20题项信度偏低(Imax≤0.2),本研究对其进行了剔除;(2)... 研究通过对200名运动员进行问卷调查,在对《运动员临场应对能力测评工具》进行修正的基础上,进一步对运动员临场应对能力的内部结构模式进行了构建与检验。结果显示:(1)由于量表中T20题项信度偏低(Imax≤0.2),本研究对其进行了剔除;(2)在量表的信、效度检验中,量表的科隆巴赫α系数=0.801(行为应对:0.784,认知应对:0.705、情绪应对:0.628)、构想效度(维度之间的相关系数r=0.509~0.654普遍小于维度与总量表之间的相关系数r=0.664~0.723)以及结构效度(χ^2/df=1.921、GFI指标=0.902、CFI=0.912等)均符合拟合标准;(3)通过对不同运动水平运动员的临场应对能力结构模式分析,发现认知应对→行为应对→情绪应对→认知应对的路径系数均较高(>0.50),仅出现情绪应对→行为应对路径系数偏低(0.398)。研究认为:运动员临场应对能力结构模式存在一种闭合的循环链式路径(即认知应对→行为应对→情绪应对→认知应对)。且二级运动员应该首先对行为应对→情绪应对和情绪应对→认知应对进行训练,而一级运动员则首选对情绪应对→认知应对进行训练。 展开更多
关键词 运动员 应对 结构 模式 构建
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Characterization of hidden rules linking symptoms and selection of acupoint using an artificial neural network model
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作者 Won-Mo Jung In-Soo Park +6 位作者 Ye-Seul Lee Chang-Eop Kim Hyangsook Lee Dae-Hyun Hahm Hi-Joon Park Bo-Hyoung Jang Younbyoung Chae 《医学前沿:英文版》 CAS CSCD 2019年第1期112-120,共9页
Comprehension of the medical diagnoses of doctors and treatment of diseases is important to understand the underlying principle in selecting appropriate acupoints.The pattern recognition process that pertains to sympt... Comprehension of the medical diagnoses of doctors and treatment of diseases is important to understand the underlying principle in selecting appropriate acupoints.The pattern recognition process that pertains to symptoms and diseases and informs acupuncture treatment in a clinical setting was explored. A total of 232 clinical records were collected using a Charting Language program. The relationship between symptom information and selected acupoints was trained using an artificial neural network (ANN). A total of 11 hidden nodes with the highest average precision score were selected through a tenfold cross-validation. Our ANN model could predict the selected acupoints based on symptom and disease information with an average precision score of 0.865 (precision, 0.911;recall, 0.811). This model is a useful tool for diagnostic classification or pattern recognition and for the prediction and modeling of acupuncture treatment based on clinical data obtained in a real-world setting. The relationship between symptoms and selected acupoints could be systematically characterized through knowledge discovery processes, such as pattern identification. 展开更多
关键词 ACUPUNCTURE INDICATION NEURAL network pattern identification prediction
世界煤炭资源流动的时空格局及成因分析
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作者 王诺 张进 +1 位作者 吴迪 赵伟杰 《自然资源学报》 CSSCI CSCD 北大核心 2019年第3期487-500,共14页
基于1990-2016年的统计数据,采用场理论研究世界煤炭资源流动的时空格局变化及其成因,揭示近30年来世界煤炭资源的流动状态及其演变过程。研究结果显示:(1)2016年世界煤炭的输出总量达12.25亿t,比1990年增加了10.13亿t,年均增长6.98%,... 基于1990-2016年的统计数据,采用场理论研究世界煤炭资源流动的时空格局变化及其成因,揭示近30年来世界煤炭资源的流动状态及其演变过程。研究结果显示:(1)2016年世界煤炭的输出总量达12.25亿t,比1990年增加了10.13亿t,年均增长6.98%,其中澳大利亚、印尼和俄罗斯等是主要的煤炭输出国,印度、日本、中国和韩国是主要的煤炭输入国;(2)以场理论的位势、流场分布、流动迹线角度分析,世界煤炭资源的流动以北美洲、中南美洲和非洲为源流场,以欧洲及欧亚大陆、中东和亚太为汇流场,在澳大利亚-东亚、印尼-东亚/印度之间形成主要运输航线;(3)资源空间分布、供需匹配程度、空间距离、市场因素和国家政策等是煤炭资源流动的主要动因。研究发现:虽然中国煤炭储量丰富,但是煤炭消费数量庞大,仅可维持72年,必须重视煤炭的进口和储备工作。该研究对于中国科学制定产业政策具有重要价值。 展开更多
关键词 煤炭 流动 格局 成因
Probing the degenerate pattern growth of {100}<011> orientation in a directionally solidified Al-4.5 wt% Cu alloy
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作者 Yumin Wang Shuangming Li +3 位作者 Zhenpeng Liu Hong Zhong Lei Xu Hui Xing 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第7期1309-1314,共6页
Degenerate pattern is a seemingly disordered morphology but it exhibits the inherently ordered crystal connected with tip-splitting and limited stability which makes it difficult to observe in the metallic system. Her... Degenerate pattern is a seemingly disordered morphology but it exhibits the inherently ordered crystal connected with tip-splitting and limited stability which makes it difficult to observe in the metallic system. Here we employ(100)[011] orientated planar-front seeds using directional solidification and reveal the fundamental origins of the degenerate pattern growth in an Al-4.5 wt% Cu alloy. We find that the spacing of the tip-splitting(λ) in the degenerate of the alloys followed a power law,λ∝V^-0.5, and the frequency(f) of the splitting was related to the growth velocity(V) by f ∝V^1.5. The dimensionless growth direction(θ/θ0) increased monotonously and approached 0.6 with faster velocity, attributed to its anisotropy in the interface kinetics. Once growth velocity exceeded a threshold, two types of pattern transitions from degenerate to regular dendrites were proposed. One of them exhibited a random and chaotic mode and the other underwent a rotation in growth direction. 展开更多
关键词 AL-CU alloy ANISOTROPY Direction solidification DEGENERATE pattern
Macroecological Patterns of Climatic Niche Breadth Variation in Lacertid Lizards
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作者 Mengchao FANG Xiaming ZHU +2 位作者 Yu DU Lin ZHANG Longhui LIN 《亚洲两栖爬行动物研究:英文版》 SCIE CSCD 2019年第1期41-47,共7页
Measuring climatic niche position and breadth may help to determine where species can occur over space and time. Using GIS-based and phylogenetic comparative methods, we investigated global patterns of variation in cl... Measuring climatic niche position and breadth may help to determine where species can occur over space and time. Using GIS-based and phylogenetic comparative methods, we investigated global patterns of variation in climatic niche breadth in lacertid lizards to test the following three hypotheses about climatic niche widths. First, does a species’ temperature or precipitation niche breadth relate to its temperature or precipitation niche position(the mean value of annual mean temperature or annual precipitation across sampled localities in the range of each species)? Second, are there trade-offs between a species’ temperature niche breadth and precipitation niche breadth? Third, does a species’ temperature or precipitation niche breadth relate to altitude or latitude? We expect that:(1) species distributed in cold regions are specialized for low-temperature environments(i.e. narrow niche breadth center around low temperatures);(2) a negative relationship between species niche breadth on temperature and precipitation axes according to the tradeoff hypothesis(i.e. species that tolerate a broad range of precipitation regimes cannot also tolerate a broad range of temperatures);(3) precipitation niche breadth decreases with altitude or latitude, whereas temperature climatic niche breadth increases with altitude or latitude. Based on the analytical results we found that:(1) temperature niche breadth and position are negatively related, while precipitation niche breadth and position are positively related;(2) there is no trade-off between temperature and precipitation niche breadths;and (3) temperature niche breadth and latitude/altitude are positively related, but precipitation niche breadth and latitude/altitude are not significantly related. Our results show many similarities with previous studies on climatic niche widths reported for amphibians and lizards, which provide further evidence that such macroecological patterns of variation in climatic niche breadths may be widespread. 展开更多
关键词 Macroecological pattern CLIMATIC NICHE BREADTH CLIMATIC NICHE POSITION LACERTIDAE
以“器官系统为中心”的教学模式在骨骼运动系统中的应用 预览
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作者 郭占鹏 袁亚江 +2 位作者 毕云龙 汪洪宇 黄米娜 《中国继续医学教育》 2019年第20期12-14,共3页
器官系统模式最早由美国西储大学提出,"器官系统为中心"的教学模式以器官系统为主线,按照各个器官系统的形态与功能及基础医学与临床医学将课程进行整合,强调完成基础与临床知识之间的融合,提高了知识的系统化及连贯性,改善... 器官系统模式最早由美国西储大学提出,"器官系统为中心"的教学模式以器官系统为主线,按照各个器官系统的形态与功能及基础医学与临床医学将课程进行整合,强调完成基础与临床知识之间的融合,提高了知识的系统化及连贯性,改善知识重复及脱节严重的现象。近年来,我国各大高校也逐步开始试行"器官系统为中心"的教学模式,我校也逐步进行了器官系统的教学,以骨骼运动系统教学为例,骨骼运动系统的教学中应用"器官系统为中心"的教学模式,优化了整体教学效果,提高学生的学习积极性,在很大程度上提高教师的教学水平,提高学生的学习质量。 展开更多
关键词 器官系统为中心 教学 骨骼运动系统 应用 模式 教学效果
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Image Based Smoke Detection Using Source Separation 预览
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作者 Ouiem Bchir Mohamed Maher Ben Ismail Norah Asiri 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2019年第3期982-989,共8页
In this paper,we propose an automatic image based smoke detection using source separation.In particular,we assume that the region of interest(smoke region)is a linear combination of smoke and background pixels,and we ... In this paper,we propose an automatic image based smoke detection using source separation.In particular,we assume that the region of interest(smoke region)is a linear combination of smoke and background pixels,and we estimate the smoke component.More specifically,we extend the linear hyperspectral unmixing techniques to the context of image based smoke detection in order to separate the smoke component from the background.The proposed approach yields promising results especially with smoke images captured outdoor. 展开更多
关键词 PATTERN RECOGNITION COMPUTER SCIENCE HYPERSPECTRAL
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Numerical simulation of flow focusing pattern and morphological changes in two-phase flow inside nozzle
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作者 Jin Zhao Zhi Ning +1 位作者 Ming Lv Geng Wang 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第1期63-71,共9页
The flow focusing nozzle is a new type of nozzle that performs effective atomization of the discrete phase by means of high-speed motion of the continuous phase.The flow pattern and its morphological changes have a si... The flow focusing nozzle is a new type of nozzle that performs effective atomization of the discrete phase by means of high-speed motion of the continuous phase.The flow pattern and its morphological changes have a significant effect on the atomization, but the influence of different parameters on the morphological change of the flow pattern remains unclear.The flow focusing pattern and morphological changes in the two-phase flow inside the nozzle were simulated numerically, based on the volume of fluid method.The results demonstrate that the ratio of the nozzle-to-capillary distance and capillary diameter, the gas–liquid velocity ratio, and capillary diameter have significant effects on the flow pattern.When the ratio of the nozzle-to-capillary distance H and capillary diameter D increases, or the capillary diameter D increases, the flow pattern tends to transform into a laminar form;however, when the gas–liquid velocity ratio V increases, the flow pattern tends to transform into a turbulence form.Furthermore, we define the cone-shaped expansion rate, cone-shaped focusing rate,and cone angle in order to study the morphological changes in the cone shape inside the nozzle.The results indicate that the morphological change of the cone shape and flow pattern transformation is interrelated.When the cone shape tends to be unstable, the flow pattern changes towards flow blurring, whereas, a stable cone indicates that the flow tends to exhibit a droplet pattern. 展开更多
关键词 Flow FOCUSING PATTERN TRANSFORMATION MORPHOLOGICAL changes Numerical simulation
Evolution of Waterfront Landscape Pattern Under Rapid Urbanization: A Case Study of Xuhui Riverside Zone in Shanghai 预览
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作者 LI Xinyu WANG Jiping 《景观研究:英文版》 2019年第2期51-53,58共4页
The urban waterfront area is in a special land-water communication zone and is an ecologically sensitive zone. It combines the characteristics of natural landscape and human landscape intertwined. The urbanization pro... The urban waterfront area is in a special land-water communication zone and is an ecologically sensitive zone. It combines the characteristics of natural landscape and human landscape intertwined. The urbanization process continues to affect the natural and cultural environment of the waterfront, and environmental issues have become increasingly prominent. Taking Xuhui Riverside Zone as an example, this paper analyses the dynamic evolution process of the landscape, aiming at revealing the impact of the evolution of landscape pattern on urban ecological environment during the process of urbanization in China, so as to provide useful references for the planning and design of the waterfront space landscape of domestic and foreign cities. 展开更多
关键词 URBANIZATION LANDSCAPE PATTERN WATERFRONT space Xuhui RIVERSIDE ZONE
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