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Activity evolution of landslides and debris flows after the Wenchuan earthquake in the Qipan catchment,Southwest China

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Journal of Mountain Science 2021年第4期18卷 932-951页

作者： shi qing-yun TANG Chuan GONG Ling-feng CHEN Ming LI Ning ZHOU Wei XIONG Jiang TANG Hai WANG Xiao-di LI Ming-wei State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China Chengdu Geological Survey Center China Geological SurveyChengdu 610081China School of Emergency Science Xihua UniversityChengdu 610039China 11th Geology Team of Zhejiang Province Wenzhou 32500China Sichuan Academy of Environmental Sciences Chengdu 610044China

The Wenchuan earthquake that occurred on 12 May 2008 induced numerous *** landslide materials were deposited on hillslopes,and deep channels were easily remobilized and transformed into debris flows by extreme *** years after the Wenchuan earthquake,debris flows were still active in the Qipangou Ravine in the quake-hit *** this paper,we continuously tracked the spatiotemporal evolution of the landslides and vegetation restoration and evaluated the evolution of debris flow activity in the Qipan catchment with the aid of a GIS platform and field investigations from 2008 to *** observed that the area with active landslides increased sharply immediately following the earthquake,and then decreased with time;however,the total area of landslides continued to increase from 6.93 km^(2)in 2008 to 10.55 km^(2)in *** active landslides shifted towards lower angles and higher elevations after *** 2009,the vegetation coverage has been gradually increasing and approaching the coverage present before the earthquake as of *** landslide activity was high and the vegetation recovery rates were rapidly rising during the first five years after the earthquake;the recovery rates then slowed over ***,we divided the evolution that occurred during the post landslide period into an active period(2008-2013),a self-adjustment period(2013-2026)and a stable period(after 2026).We then proposed a quantitative model to determine the trends of landslide activity rates and NDVI values in the catchment,which indicated that the landslide activities and postseismic vegetation restoration rates in this catchment will return to preseismic levels within approximately two *** also analysed the runout volumes of the debris flows after the earthquakes(Diexi and Wenchuan)and the standard deviation of the vegetation coverage and predicted that the debris flow activities will last for an additional 50 years or more.

关键词： Evolution of debris flow activity Seismic landslides Vegetation recovery Qipan catchment

以共同育儿为业:跨越儿童抚育的家庭边界——以一个城市社区的“抱团养娃”实践为例

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妇女研究论丛 2022年第1期 23-34,61页

作者：施芸卿中国社会科学院社会学研究所北京100732

本文聚焦于城市化背景下的"抱团养娃"实践,深入探讨在抚育职责被"家庭化"的当下,抚育实践如何在一定程度上重新跨越"家庭"的边界。以社区共育为基点,妈妈们的努力既从私人层面上为在陌生城市中资源不足的小家庭找到更多社会支持,又在公... 详细信息

本文聚焦于城市化背景下的"抱团养娃"实践,深入探讨在抚育职责被"家庭化"的当下,抚育实践如何在一定程度上重新跨越"家庭"的边界。以社区共育为基点,妈妈们的努力既从私人层面上为在陌生城市中资源不足的小家庭找到更多社会支持,又在公共层面上带动孩子们以温度和情感重塑社区认同、黏合社会转型带来的制度缝隙,体现出独特的现实意义与支持力量。"以共同育儿为业"背后,是女性试图在既有的结构约束下找到被私人化的抚育照料重担与公共生活之间的连接点,在本研究中体现为共育支持网络的形成、共育友好空间的营造、亲子活动内容的生产和共育文化的建构四个方面。这为思考如何将"社会"重新带回抚育实践中提供了想象,也拓宽了对女性主体性的理解。

关键词：社区共育社会再生产抚育实践自然养育过程—事件分析

数字不平等的再生产——以大学生网络使用为例

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兰州大学学报（社会科学版） 2014年第6期42卷 69-75页

作者：施芸卿中国社会科学院社会学研究所北京100732

基于中国社科院"大学生就业、生活及价值观调查"12所高校的数据,从数字资源、数字生活方式以及数字自主性这三个维度,对当前大学生网络使用中的数字不平等现象进行了分析。研究发现,当前大学生的互联网使用中存在着数字不平等的多级阶梯... 详细信息

基于中国社科院"大学生就业、生活及价值观调查"12所高校的数据,从数字资源、数字生活方式以及数字自主性这三个维度,对当前大学生网络使用中的数字不平等现象进行了分析。研究发现,当前大学生的互联网使用中存在着数字不平等的多级阶梯,体现出技术普及的动态过程中遭遇到的社会边界。在阶层及外部资源上占有优势的群体,能更多地占据多样化的数字资源,更深入地融入数字生活以及有更大的自由获取信息,现实中的不平等正在数字空间中被持续地再生产出来。研究还注意到了使用者们面对这种不平等做出的一些努力,他们有意识地将互联网作为一种增强个人人力资本和表达能力的工具,以期待对个人境遇有所改善。

关键词：数字资源数字生活方式数字自主性数字不平等大学生

再造日常——老城复兴中“活”的公共文化再生产

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社会学评论 2023年第1期11卷 39-60页

作者：施芸卿中国社会科学院社会学研究所

当前老城复兴中的人文转向尝试将“人”及其“真实生活”带回更新进程,但“活”的公共文化再生产始终是个难题。作为前沿文化实践,“再造日常”搭建了不同人群间的沟通对话机制,重塑了制度内外对接转化机制,需在城市更新和社会转型的双... 详细信息

当前老城复兴中的人文转向尝试将“人”及其“真实生活”带回更新进程,但“活”的公共文化再生产始终是个难题。作为前沿文化实践,“再造日常”搭建了不同人群间的沟通对话机制,重塑了制度内外对接转化机制,需在城市更新和社会转型的双重意义上来理解。本文以一个社区公共文化空间的运营及新型公共文化建构为例,从“找回公众”“消融区隔”和“淡化权威”三方面展现这个界限消抹和连接再造的过程,其背后是空间活化、文化再生及地方治理品牌化三重机制的叠加,它使老城生活在空间、人群和制度上由表及里地向外打开。通过日常的再造,行动者以文化再生产的柔性力量探入国家-社会连接处的肌理,推动了转型,这也使关于“社会的生产”的讨论变得更为复杂。

关键词：再造日常文化再生产空间活化社区参与式艺术

Effect of pyrite content on chalcopyrite flotation under different regrinding conditions

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 49-57页

作者： Zejun Wang qing shi Guofan Zhang Yuxuan Zhu Binbin Li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China

This study aimed to investigate the effect of varying pyrite(Py)content on copper(Cu)in the presence of different regrinding conditions,which were altered using different types of grinding media:iron,ceramic balls,and their mixture,followed by flotation in the cleaner *** flotation performance of rough Cu concentrate can be improved by changing the regrinding conditions based on the Py *** electron microscopy,X-ray spectrometry,ethylenediaminetetraacetic acid disodium salt extraction,and X-ray photoelectron spectroscopy studies illustrated that when the Py content was high,the use of iron media in regrinding promoted the generation of hydrophilic Fe OOH on the surface of Py and improved the Cu *** ceramic medium with a low Py content prevented excessive Fe OOH from covering the surface of chalcopyrite(Cpy).Electrochemical studies further showed that the galvanic corrosion current of Cpy-Py increased with the addition of Py and became stronger with the participation of iron media.

关键词： chalcopyrite regrinding media pyrite galvanic corrosion flotation

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可逆的DCT整型变换与无失真图像压缩

软件学报 2000年第5期11卷 620-627页

作者：闫宇松 *** 石青云北京大学信息科学中心视觉与听觉信息处理国家重点实验室

使用提升的方法 ,利用 FFT( fast Fourier transform)的蝶型构造 ,完成了 FFT与 DCT( discrete cosinetransform)的从整数到整数的变换 .变换本身是可逆的。

关键词： FFT DCT 整型变换无失真图像压缩计算机

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通用的高性能算术编码器

计算机研究与发展 1999年第12期36卷 1477-1483页

作者：闫宇松石青云北京大学视觉与听觉信息处理国家重点实验室北京100871

文中基于成熟的ＱＭ算术编码器，提出了对称二叉树的编码方式ＳＴＱＭ和最优二叉树的编码方式ＯＴＱＭ．ＳＴＱＭ与ＯＴＱＭ均是大符号集熵编码器．它们不仅保持了ＱＭ编码器的超过９６％的编码效率，也保持了它高速运算的特性．... 详细信息

文中基于成熟的ＱＭ算术编码器，提出了对称二叉树的编码方式ＳＴＱＭ和最优二叉树的编码方式ＯＴＱＭ．ＳＴＱＭ与ＯＴＱＭ均是大符号集熵编码器．它们不仅保持了ＱＭ编码器的超过９６％的编码效率，也保持了它高速运算的特性．其中ＯＴＱＭ可以动态的调整码树结构，使得编码速度达到理论最优值．ＳＴＱＭ由于可并行性和逻辑线路设计简单等特点。

关键词：算术编码器图像编码数据压缩编码器

Metallogenic model of sandstone-hosted copper deposits:a case study from the Paleogene in Jiashi area,northwestern China

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Journal of Palaeogeography 2025年第01期14卷 105-125页

作者： Long-qing shi Xing-Yue Qu Carlos Zavala Yang Li College of Earth Science and Engineering Shandong University of Science and Technology Geology Department Universidad Nacional del Sur Geología de Cuencas Sedimentarias (GCS) Argentina Institute of Energy Peking University Ordos Research Institute of Energy Peking University Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and Technology

Sandstone-hosted copper deposits,a type of Sediment-Hosted Stratiform Copper (SSC) deposits,are widely distributed *** economically viable deposits of SSC are relatively scarce,they account for approximately 30%of the world's total discovered copper ***,there is still a lack of comprehensive and in-depth research into the depositional and metallogenic models of these *** Jiashi area of the Tarim Basin in northwestern China,known for its economically significant Paleogene SSC deposit,lacks in-depth studies on metallogenic *** address this,field profile observations were conducted to analyze the sedimentary evolution,sequence stratigraphy,and tectonism of the Paleogene strata in the Jiashi *** with elemental geochemical analysis of samples,the provenance of sediment,and the source of metallogenic materials,a robust metallogenic model was *** results reveal the influence of provenance for the origin of Paleogene copper-rich *** evolution played a crucial role in controlling the distribution of copper and sulfur elements,as well as the spatial arrangement of metallogenic ***,nappe movement potentially generated faults,allowing upward movement of basin fluids,which played a crucial role in the formation of copper deposits within sandstone-hosted ***,this study offers a comprehensive analysis of the metallogenic processes involved in sandstone-hosted copper deposits,thereby contributing significant insights to the broader research on SSC deposits worldwide.

关键词： Tarim Basin Paleogene Sandstone-hosted copper deposits Metallogenic material source Metallogenic model

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一个能去噪和保持真实感的各向异性扩散方程

计算机学报 1999年第11期22卷 1133-1137页

作者：林宙辰石青云北京大学视觉与听觉信息处理国家重点实验室北京100871

提出了一个由各向异性扩散方程定义的非线性图像滤波算子．与Ｐｅｒｏｎａ，Ｍａｌｉｋ和Ｃａｔｔé等人提出的类似算子一样，该算子能够去噪声，而且性能很稳定．另一方面，它也能增强阶跃状强边缘并保持边缘的位置．所不同的是，它... 详细信息

提出了一个由各向异性扩散方程定义的非线性图像滤波算子．与Ｐｅｒｏｎａ，Ｍａｌｉｋ和Ｃａｔｔé等人提出的类似算子一样，该算子能够去噪声，而且性能很稳定．另一方面，它也能增强阶跃状强边缘并保持边缘的位置．所不同的是，它还能保持图像中有意义的较强的尖峰和窄边缘．由于这几方面的性能，处理后的自然图像看上去不但清晰度和对比度得到增强，而且有意义的细节也得到保留，很有层次感．该算子特别适用于去除非纹理图像上均匀分布的噪声．实验结果令人满意．

关键词：各向异性扩散方程图像处理噪声图像分析