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煤矿智能化(初级阶段)技术体系研究与工程进展 被引量:221
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作者 王国法 任怀伟 +18 位作者 庞义辉 曹现刚 赵国瑞 陈洪月 杜毅博 毛善君 徐亚军 任世华 程建远 刘思平 范京道 吴群英 孟祥军 杨俊哲 余北建 宣宏斌 孙希奎 张殿振 王海波 《煤炭科学技术》 CAS CSCD 北大核心 2020年第7期1-27,共27页
煤炭是实现清洁高效利用的最经济、最可靠的能源,煤炭资源的智能、安全、高效开发与低碳清洁利用是实现我国煤炭工业高质量发展的核心技术支撑。基于我国煤矿智能化初级阶段的发展要求,开展了煤矿智能化技术体系研究和工程建设,进行了... 煤炭是实现清洁高效利用的最经济、最可靠的能源,煤炭资源的智能、安全、高效开发与低碳清洁利用是实现我国煤炭工业高质量发展的核心技术支撑。基于我国煤矿智能化初级阶段的发展要求,开展了煤矿智能化技术体系研究和工程建设,进行了智能化煤矿顶层设计研究,以"矿山即平台"的理念将智能化煤矿整体架构分为设备层、基础设施层、服务层与应用层,实现煤矿生产、安全、生态、保障的智能化闭环管理。针对智能化煤矿存在的信息孤岛问题,开展了多源异构数据建模、特征提取与数据挖掘等技术研究,研发了基于数据驱动的信息实体建模与更新技术;研究了智能化煤矿高精度三维地质模型构建方法,通过在刮板输送机上布设巡检机器人与三维激光扫描仪,将三维激光扫描数据与地质模型数据、采煤机位姿数据、采煤机摇臂截割数据进行有效融合,获取采煤机的实时截割曲线,通过比对采煤机实际截割曲线与地质模型的煤岩层分界面曲线,实现基于地质模型动态更新的煤层厚度自适应截割控制方法;研发了工作面采掘接续智能设计技术,实现了接续工作面图纸、规程、规范的智能设计,大幅降低了采掘接续过程中的重复劳动;研究了掘锚一体机的位姿检测与导航技术、自动打锚杆技术、自动铺网技术、巷道三维建模与质量监测技术,探索了基于远程视频监控的巷道智能高效掘进技术与装备;以"有人巡视,无人操作"为特征的智能化开采工作面在全国逐渐推广应用,开展了基于三维地质模型动态更新的采煤机自适应截割技术研发与实践,在部分矿区取得较好的试验效果。分析了智能分选技术、智能辅助运输技术、5G通信技术在煤矿井上下应用存在的技术难点及解决的技术路径,从技术研发角度系统分析了制约智能化煤矿建设的关键技术难题。详细阐述 展开更多
关键词 煤矿智能化 顶层设计 智能化开采 智能掘进 三维地质模型 标准体系
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Prevalence of Nontraumatic Osteonecrosis of the Femoral Head and its Associated Risk Factors in the Chinese Population: Results from a Nationally Representative Survey 被引量:177
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作者 De-Wei Zhao Mang Yu +23 位作者 Kai Hu Wei Wang Lei Yang Ben-Jie Wang Xiao-Hong Gao Yong-Ming Guo Yong-Qing xu Yu-Shan Wei Si-Miao Tian fan Yang Nan Wang Shi-Bo Huang Hui Xie Xiao-Wei Wei Hai-Shen Jiang Yu-Qiang Zang Jun Ai Yuan-Liang Chen Guang-Hua Lei Yu-Jin Li Geng Tia Zong-Sheng Li Yong Cao Li Ma 《Chinese Medical Journal》 SCIE CAS CSCD 2015年第21期2843-2850,共8页
Background: Nontraumatic osteonecrosis of the femoral head (NONFH) is a debilitating disease that represents a significant financial burden for both individuals and healthcare systems. Despite its significance, how... Background: Nontraumatic osteonecrosis of the femoral head (NONFH) is a debilitating disease that represents a significant financial burden for both individuals and healthcare systems. Despite its significance, however, its prevalence in the Chinese general population remains unknown. This study aimed to investigate the prevalence of NONFH and its associated risk factors in the Chinese population. Methods: A nationally representative survey of 30,030 respondents was undertaken from June 2012 to August 2013. All participants underwent a questionnaire investigation, physical examination of hip, and bilateral hip joint X-ray and/or magnetic resonance imaging exalnination. Blood samples were taken after overnight fasting to test serum total cholesterol, triglyceride, and high-density lipoprotein (HDL) and low-density lipoprotein (LDL) levels. We then used multivariate logistic regression analysis to investigate the associations between various metabolic, demographic, and lifestyle-related variables and NONFH. Results: NONFH was diagnosed in 218 subjects (0.725%) and the estimated NONFH cases were 8.12 million among Chinesepeople aged 15 years and over. The prevalence of NONFH was significantly higher in males than in females (1.02% vs. 0.51%, x^2 = 24.997, P 〈 0.001 ). Among NONFH patients, North residents were subjected to higher prevalence of NONFH than that of South residents (0.85% vs. 0.61%,x^2= 5.847, P = 0.016). Our multivariate regression analysis showed that high blood levels oftriglycerides, total cholesterol, LDL-cholesterol, and non-H DL-cholesterol, male, urban residence, family history of osteonecrosis of the femoral head. heavy smoking, alcohol abuse and glucocorticoid intake, overweight, and obesity were all significantly associated with an increased risk of NONFH. Conclusions: Our findings highlight that NONFH is a significantpublic health challenge in China and underscore the need for policy measures on the national level. Furthermore, NONFH shares a number of risk 展开更多
关键词 Nontraumatic Osteonecrosis of the Femoral Head PREVALENCE Risk Factors
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基于改进型YOLO的复杂环境下番茄果实快速识别方法 被引量:123
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作者 刘芳 刘玉坤 +3 位作者 林森 郭文忠 徐凡 张白 《农业机械学报》 EI CAS CSCD 北大核心 2020年第6期229-237,共9页
为实现温室环境下农业采摘机器人对番茄果实的快速、精确识别,提出了一种改进型多尺度YOLO算法(IMS-YOLO)。对YOLO网络模型进行筛选和改进,设计了一种含有残差模块的darknet-20主干网络,同时融合多尺度检测模块,构建了一种复杂环境下番... 为实现温室环境下农业采摘机器人对番茄果实的快速、精确识别,提出了一种改进型多尺度YOLO算法(IMS-YOLO)。对YOLO网络模型进行筛选和改进,设计了一种含有残差模块的darknet-20主干网络,同时融合多尺度检测模块,构建了一种复杂环境下番茄果实快速识别网络模型。该网络模型层数较少,能够提取更多特征信息,且采用多尺度检测结构,同时返回番茄果实的类别和预测框,以此提升番茄果实检测速度和精度。采用自制的番茄数据集对IMS-YOLO模型进行测试,并分别对改进前后网络的检测性能以及主干网络层数对特征提取能力的影响进行了对比试验。试验结果表明,IMS-YOLO模型对番茄图像的检测精度为97.13%,准确率为96.36%,召回率为96.03%,交并比为83.32%,检测时间为7.719 ms;对比YOLO v2和YOLO v3等网络模型,IMS-YOLO模型可以同时满足番茄果实检测的精度和速度要求。最后,通过番茄温室大棚采摘试验验证了本文模型的可行性和准确性。 展开更多
关键词 番茄 采摘机器人 识别 深度学习 改进型YOLO darknet-20
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植物残体向土壤有机质转化过程及其稳定机制的研究进展 被引量:120
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作者 汪景宽 徐英德 +9 位作者 丁凡 高晓丹 李双异 孙良杰 安婷婷 裴久渤 李明 王阳 张维俊 葛壮 《土壤学报》 CAS CSCD 北大核心 2019年第3期528-540,共13页
土壤有机质的数量和质量不仅是衡量土壤肥力状况的核心要素,其形成、转化及稳定过程还与全球气候变化密切相关。植物残体是土壤有机质的初始来源,但由于其腐解过程的复杂、多变性以及土壤有机质、微生物的高度异质性,植物残体向土壤有... 土壤有机质的数量和质量不仅是衡量土壤肥力状况的核心要素,其形成、转化及稳定过程还与全球气候变化密切相关。植物残体是土壤有机质的初始来源,但由于其腐解过程的复杂、多变性以及土壤有机质、微生物的高度异质性,植物残体向土壤有机质的转化和稳定机理尚不十分明确。本文介绍并讨论了近年来关于植物残体向土壤有机质转化相关研究的新发现,探讨了微生物源和植物源有机质对土壤有机质的贡献,概述了土壤有机质形成的微生物驱动机制,并综述了植物残体输入后土壤有机质稳定性的相关研究,最后对该研究领域未来的发展进行展望,以期能够为科学地提高土壤的固碳能力提供参考。 展开更多
关键词 土壤有机质 腐殖质 碳循环 微生物 稳定性
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Identification of a novel coronavirus causing severe pneumonia in human:a descriptive study 被引量:113
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作者 Li-Li Ren Ye-Ming Wang +33 位作者 Zhi-Qiang Wu Zi-Chun Xiang Li Guo Teng xu Yong-Zhong Jiang Yan Xiong Yong-Jun Li Xing-Wang Li Hui Li Guo-Hui fan Xiao-Ying Gu Yan Xiao Hong Gao Jiu-Yang xu fan Yang Xin-Ming Wang Chao Wu Lan Chen Yi-Wei Liu Bo Liu Jian Yang Xiao-Rui Wang Jie Dong Li Li Chao-Lin Huang Jian-Ping Zhao Yi Hu Zhen-Shun Cheng Un-Lin Liu Zhao-Hui Qian Chuan Qin Qi Jin Bin Cao Jian-Wei Wang 《Chinese Medical Journal》 SCIE CAS CSCD 2020年第9期1015-1024,共10页
Background:Human infections with zoonotic coronaviruses(CoVs),including severe acute respiratory syndrome(SARS)-CoV and Middle East respiratory syndrome(MERS)-CoV,have raised great public health concern globally.Here,... Background:Human infections with zoonotic coronaviruses(CoVs),including severe acute respiratory syndrome(SARS)-CoV and Middle East respiratory syndrome(MERS)-CoV,have raised great public health concern globally.Here,we report a novel batorigin CoV causing severe and fatal pneumonia in humans.Methods:We collected clinical data and bronchoalveolar lavage(BAL)specimens from five patients with severe pneumonia from Wuhan Jinyintan Hospital,Hubei province,China.Nucleic acids of the BAL were extracted and subjected to next-generation sequencing.Virus isolation was carried out,and maximum-likelihood phylogenetic trees were constructed.Results:Five patients hospitalized from December 18 to December 29,2019 presented with fever,cough,and dyspnea accompanied by complications of acute respiratory distress syndrome.Chest radiography revealed diffuse opacities and consolidation.One of these patients died.Sequence results revealed the presence of a previously unknownβ-CoV strain in all five patients,with 99.8%to 99.9%nucleotide identities among the isolates.These isolates showed 79.0%nucleotide identity with the sequence of SARS-CoV(GenBank NC_004718)and 51.8%identity with the sequence of MERS-CoV(GenBank NC_019843).The virus is phylogenetically closest to a bat SARS-like CoV(SL-ZC45,GenBank MG772933)with 87.6%to 87.7%nucleotide identity,but is in a separate clade.Moreover,these viruses have a single intact open reading frame gene 8,as a further indicator of bat-origin CoVs.However,the amino acid sequence of the tentative receptor-binding domain resembles that of SARS-CoV,indicating that these viruses might use the same receptor.Conclusion:A novel bat-borne CoV was identified that is associated with severe and fatal respiratory disease in humans. 展开更多
关键词 Bat-origin CORONAVIRUS Zoonotic transmission PNEUMONIA ETIOLOGY Next-generation sequencing
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中国马铃薯病虫害发生情况与农药使用现状 被引量:108
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作者 徐进 朱杰华 +9 位作者 杨艳丽 汤浩 吕和平 樊明寿 石瑛 董道峰 王贵江 王万兴 熊兴耀 高玉林 《中国农业科学》 CAS CSCD 北大核心 2019年第16期2800-2808,共9页
作为继水稻、玉米和小麦之后的第四大主粮作物,马铃薯在保障我国粮食安全、精准扶贫、种植业结构调整以及农业产业转型升级中发挥着至关重要的作用。我国马铃薯的种植面积和总产量均位居世界首位,但单产水平因病虫害等瓶颈因素的制约低... 作为继水稻、玉米和小麦之后的第四大主粮作物,马铃薯在保障我国粮食安全、精准扶贫、种植业结构调整以及农业产业转型升级中发挥着至关重要的作用。我国马铃薯的种植面积和总产量均位居世界首位,但单产水平因病虫害等瓶颈因素的制约低于世界平均水平。在国家重点研发项目的资助下,项目组在马铃薯六大优势产区开展了有害生物疫情监测和农药使用现状普查工作。明确了我国马铃薯生产上的主要病虫害共计27种,提出以晚疫病、早疫病、黑痣病、枯萎病、黑胫病、疮痂病、金针虫、蛴螬、二十八星瓢虫、马铃薯块茎蛾、蚜虫、蓟马等"六病六虫"为重点防控对象,根据各区域情况兼顾青枯病、环腐病、黄萎病、粉痂病等病虫害的防控。探明了我国马铃薯单位面积农药施用次数和施用量分别为17次和40.03 kg·hm^-2,高于全国平均水平的4.16次和3.49 kg·hm^-2。马铃薯现有农药登记产品防治对象的覆盖范围严重不足,青枯病、疮痂病、粉痂病等重要病虫害面临无登记农药可用的窘境。在农药减施策略方面,提出践行有害生物综合治理方针。建立马铃薯病虫害监测预警和早期精确诊断技术体系,为制定科学防控策略,适时精准施药奠定基础。选育推广抗病、虫品种,优化品种布局。适时播种、合理间套作,从时空两个维度阻隔规避马铃薯有害生物的侵染。种薯源头管控,完善种薯认证监管体系。扩大合格脱毒种薯的应用面积,大力推广种薯处理技术。研发推广化学农药高效施用技术与绿色防控替代技术是实现马铃薯化学农药减施的核心驱动。 展开更多
关键词 马铃薯 病虫害 农药减施
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Progress in carbon dioxide separation and capture: A review 被引量:101
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作者 Hongqun Yang Zhenghe xu +4 位作者 Maohong fan Rajender Gupta Rachid B Slimane Alan E Bland Ian Wright 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第1期14-27,共14页
This article reviews the progress made in CO2 separation and capture research and engineering. Various technologies, such as absorption, adsorption, and membrane separation, are thoroughly discussed. New concepts such... This article reviews the progress made in CO2 separation and capture research and engineering. Various technologies, such as absorption, adsorption, and membrane separation, are thoroughly discussed. New concepts such as chemical-looping combustion and hydrate-based separation are also introduced briefly. Future directions are suggested. Sequestration methods, such as forestation, ocean fertilization and mineral carbonation techniques are also covered. Underground injection and direct ocean dump are not covered. 展开更多
关键词 coal flue gas carbon dioxide SORBENT absorption adsorption membrane SEPARATION SEQUESTRATION
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境身合一:沉浸式体验的内涵建构、实现机制与教育应用--兼论AI+沉浸式学习的新场域 被引量:82
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作者 徐铷忆 陈卫东 +4 位作者 郑思思 张宇帆 袁凡 葛文硕 魏荟敏 《远程教育杂志》 CSSCI 北大核心 2021年第1期28-40,共13页
伴随着移动互联网+、扩展现实(XR)、泛在智能、大数据、5G、全息与传感等新技术的飞速发展,极大地赋能了人类的学习、工作与生活方式,沉浸式体验已越来越受到重视与应用。尤其在教育领域,沉浸式体验所具有的无边界、交互性、愉悦性、具... 伴随着移动互联网+、扩展现实(XR)、泛在智能、大数据、5G、全息与传感等新技术的飞速发展,极大地赋能了人类的学习、工作与生活方式,沉浸式体验已越来越受到重视与应用。尤其在教育领域,沉浸式体验所具有的无边界、交互性、愉悦性、具身性等特征,创造出了更优质的学习空间,学习者可进行各种模拟体验,为其主动投入学习、提升认知、培养移情与关联能力等提供可能。沉浸式体验是由技术、内容、交互三大机制相互作用所共同构成“境身合一”般的场景与感官感受。这种境身合一的沉浸式学习体验,不仅可应用于认知领域、动作技能领域与情感领域的教与学;也可用于培养学习者的创新性思维和想象力,还可从游戏化智慧学习、XR+CPS仿真实验室、泛在协作学习场域、全域学习生态链、沉浸式群体探究学习和高自由度生成叙事学习空间等方面,进一步赋能AI+沉浸式学习新场域。 展开更多
关键词 境身合一 沉浸式体验 实现机制 场域建构 教育应用 沉浸式学习 泛在智能
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Crop Yield and Soil Responses to Long-Term Fertilization on a Red Soil in Southern China 被引量:78
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作者 ZHANG Hui-Min WANG Bo-Ren +1 位作者 xu Ming-Gang fan Ting-Lu 《Pedosphere》 SCIE CAS CSCD 2009年第2期199-207,共9页
A 15-year fertilization experiment with different applications of inorganic N,P and K fertilizers and farmyard manure (M)was conducted to study the yield and soil responses to long-term fertilization at Qiyang,Hunan P... A 15-year fertilization experiment with different applications of inorganic N,P and K fertilizers and farmyard manure (M)was conducted to study the yield and soil responses to long-term fertilization at Qiyang,Hunan Province,China. Average grain yields of wheat and corn(1 672 and 5 111 kg ha-1,respectively)for the treatment NPKM were significantly higher than those(405 and 310 kg ha-1)of the unfertilized control and single inorganic fertilizer treatments.Compared with the corresponding initial values of the experiment,all treatments showed a yield decline of 9 to 111 kg ha-1 year-1 in wheat and 35 to 260 kg ha-1 year-1 in corn,respectively,and a significant pH decline of 0.07 to 0.12 pH year?1,except for the treatments PK and NPKM.After long-term fertilization,the soil organic C,soil available P,exchangeable Ca2+ and Mg2+and available Cu2+and Zn2+contents were higher in the treatment NPKM than in the treatments applied with inorganic fertilizer only.Compared to the treatment NPK,the treatment NPKM,where manure partially replaced inorganic N,had a positive impact on arresting the decline of soil pH.This improved grain yields of wheat and corn, suggesting that application of NPK fertilizer in combination with farmyard manure is important to maintain soil fertility and buffering capacity in red soil. 展开更多
关键词 CORN long-term fertilization red soil WHEAT yield
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中国辣椒育种60年回顾与展望 被引量:77
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作者 邹学校 胡博文 +9 位作者 熊程 戴雄泽 刘峰 欧立军 杨博智 刘周斌 索欢 徐昊 朱凡 远方 《园艺学报》 CAS CSCD 北大核心 2022年第10期2099-2118,共20页
本文中介绍了中国辣椒育种60年的重要成就,包括种质资源的搜集、鉴定、评价、利用和创制,杂种优势利用、花药培养、分子育种、多抗性育种、穿梭育种等育种技术创新取得的重要贡献,20世纪80年代前的辣椒育种和1980年后辣椒育种国家科技... 本文中介绍了中国辣椒育种60年的重要成就,包括种质资源的搜集、鉴定、评价、利用和创制,杂种优势利用、花药培养、分子育种、多抗性育种、穿梭育种等育种技术创新取得的重要贡献,20世纪80年代前的辣椒育种和1980年后辣椒育种国家科技攻关的情况。20世纪80年代以来中国辣椒育种在产业需求拉动下经过高产育种、生育期育种、抗病育种、耐贮藏运输育种、加工专用品种育种、高品质育种、机械化采收育种等几个阶段,经40多年的发展,已全面建立了现代化的辣椒商业育种体系,育种水平世界领先,具有自主知识产权国产品种的市场占有率95%以上。中国辣椒育种形成中国独特的行业特点,如门槛低、风险小、见效快、队伍大、品种多、成效好等,但也存在一些严重影响辣椒种业发展的问题,如辣椒品种同质化现象严重、辣椒种子经营企业难以做大、辣椒分子育种技术研究进展缓慢、温室长季节栽培品种、观赏辣椒品种明显落后发达国家导致种子主要依靠进口等。因此,中国辣椒育种未来发展方向是高品质育种、适合机械化生产品种的育种和具有药用和功能成分品种的育种、特色优异地方品种的开发及育种、繁种技术的创新。 展开更多
关键词 辣椒 育种 辣椒育种特点 种业存在问题 发展趋势
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Current pattern of Chinese dialysis units: a cohort study in a representative sample of units 被引量:74
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作者 ZHOU Qiu-gen JIANG Jian-ping +14 位作者 WU Sheng-jie TIAN Jian-wei CHEN Jiang-hua YU xue-qing CHEN Ping-yan MEI Chang-lin XIONG Fei SHI Wei ZHOU Wei LIU xu-sheng SUN Shi-ren XIE Di LIU Jun xu Xin HOU fan-fan 《Chinese Medical Journal》 SCIE CAS CSCD 2012年第19期3434-3439,共6页
Background Understanding the characteristics of Chinese dialysis patients and the current practice trends is the first step to evaluate the association between practice pattern and outcome in these populations. In the... Background Understanding the characteristics of Chinese dialysis patients and the current practice trends is the first step to evaluate the association between practice pattern and outcome in these populations. In the present study, we evaluated the status of medical treatment and characteristic features of chronic dialysis patients in China. Methods Through a clustering sampling, we selected 9 centers from the largest dialysis facilities in 6 cities around China. All adult undergoing dialysis in the selected units were screened. A total of 2388 (1775 on hemodialysis (HD) and 613 on peritoneal dialysis (PD)) patients were finally enrolled. All data were collected at enrollment on the bases of review of medical records. Results In this cohort, 1313 (55.0%) were male. The mean age was 54 years old. The median time for dialysis was 26 months (12-51 months). Seventy-five percent of patients were on HD and 25.0% on PD. Among PD patients, about 21% patients did not receive dialysis adequacy. For HD patients, about 14.0% of them did not achieve dialysis adequacy when the target of kt/V was set as 1.2. Only 44.7% of patients achieved blood pressure target of 140/90 mmHg. About 60% of patients did not reach the hemoglobin target of 110 g/L even though 85.0% of them were treated with erythropoietin. In addition, 48.5% of the patients had uncontrolled mineral metabolism revealed by the high calcium-phosphate product. Compared with HD patients, higher level of serum glucose, triglyceride, and total and low density lipoprotein cholesterol were more common in PD patients. Conclusions This observational study suggests that many Chinese dialysis patients did not achieve the therapeutic target, particularly in blood pressure control, anemia correction, and mineral balance. PD patients were more likely to suffer metabolic disturbance. 展开更多
关键词 chronic dialysis practice pattern OUTCOME China
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帕金森病(颤拘病)中医临床诊疗专家共识 被引量:73
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作者 雒晓东 李哲 +18 位作者 朱美玲 徐评议 郭新峰 吴智兵 高敏 缪晓路 谭峰 吕少华 王青 王成银 毕尚青 范玉珍 罗恩丽 苏巧珍 郑春叶 郭友华 伍犹梁 刘梓言 周志成 《中医杂志》 CSCD 北大核心 2021年第23期2109-2116,共8页
帕金森病是一种中脑黑质纹状体通路障碍的缓慢进展变性疾病,多见于中老年人,以运动迟缓、静止性震颤和肌强直为主要临床特征;。帕金森病目前仍以药物治疗为主,但迄今尚无根治药物。复方左旋多巴类仍是控制运动症状的最有效西药,但几乎... 帕金森病是一种中脑黑质纹状体通路障碍的缓慢进展变性疾病,多见于中老年人,以运动迟缓、静止性震颤和肌强直为主要临床特征;。帕金森病目前仍以药物治疗为主,但迄今尚无根治药物。复方左旋多巴类仍是控制运动症状的最有效西药,但几乎所有病例均需终身服药以控制症状,很多患者常因不能耐受药物副作用被迫停药;而脑深部电刺激术虽可明显改善症状,但仍不能根治,也不能控制疾病进展;。 展开更多
关键词 被迫停药 脑深部电刺激术 运动迟缓 变性疾病 运动症状 肌强直 帕金森病 静止性震颤
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中国绿色经济发展水平测度及其影响因素研究 被引量:73
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作者 徐晓光 樊华 +1 位作者 苏应生 郑尊信 《数量经济技术经济研究》 CSSCI CSCD 北大核心 2021年第7期65-82,共18页
研究目标:测度中国绿色经济发展水平并研究影响绿色经济发展水平的因素。研究方法:在运用熵思想对构建的绿色经济发展指标体系进行测算后,结合运用地理加权回归模型(GWR)确定全局因素及局部因素,并对局部因素回归系数显著性进行分析。... 研究目标:测度中国绿色经济发展水平并研究影响绿色经济发展水平的因素。研究方法:在运用熵思想对构建的绿色经济发展指标体系进行测算后,结合运用地理加权回归模型(GWR)确定全局因素及局部因素,并对局部因素回归系数显著性进行分析。研究发现:中国绿色经济发展水平整体而言呈上升态势。影响绿色经济发展水平的因素在不同年份作用范围不同,同一年份相同局部因素对各省份的影响显著性也不相同。研究创新:构建中国绿色经济发展水平指标体系,揭示绿色经济发展水平的整体趋势,探明不同影响因素的作用范围及其影响的显著性。研究价值:为政府制定持续深入推进绿色经济发展的有关政策提供依据。 展开更多
关键词 绿色经济 地理加权回归模型
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数智融合:数据驱动下教与学的演进与未来趋向--兼论图形化数据智能赋能教育的新形态 被引量:72
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作者 郑思思 陈卫东 +2 位作者 徐铷忆 袁凡 褚乐阳 《远程教育杂志》 CSSCI 北大核心 2020年第4期27-37,共11页
随着5G、大数据、XR和人工智能等技术的发展和应用,人类已经进入到数智融合(BD+AI)时代。图形化是当今大数据的重要形式之一,可以快速耦合异构数据,为各类教育主体提供决策支持。图形化数据驱动教育的核心特征,包括实时互动、埋点采集... 随着5G、大数据、XR和人工智能等技术的发展和应用,人类已经进入到数智融合(BD+AI)时代。图形化是当今大数据的重要形式之一,可以快速耦合异构数据,为各类教育主体提供决策支持。图形化数据驱动教育的核心特征,包括实时互动、埋点采集、深度分析和循证决策。在教育领域,图形化数据包括状态、过程、关系和支持四个维度的不同类型,具有直观性、全景性、交互性、智能性、可扩展性和叙事性等特性,在学生学习、教师教学、学习评价以及教学管理均可有效应用。数智融合使得图形化数据可以从脑机技术、全域交互、人机融合、虚实共生、教育均衡、教育智脑六个方面,赋能未来教育新形态。 展开更多
关键词 数据驱动 图形化数据 教育应用 数智融合 数字孪生 全息课堂 脑机技术 数据智能
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Association of H.pylori infection with gastric carcinoma:a Meta analysis 被引量:66
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作者 Fu-Bo xue~1 Yong-Yong xu~1 Yi Wan~1 Bo-Rong Pan~2 Jun Ren~2 Dai-Ming fan~3 1 Department of Health Statistics,Department of2 Oncology3 Gastroenterology of XiJing Hospital,the Fourth Military Medical University,Xi’an 710032,Shaanxi Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第6期801-804,共4页
AIM: To follow the principles of evidence based medicine to reach the integrated results of these studies. METHODS: Twenty-one papers of case-control studies were selected, including 11 on gastric cancer,7 on precance... AIM: To follow the principles of evidence based medicine to reach the integrated results of these studies. METHODS: Twenty-one papers of case-control studies were selected, including 11 on gastric cancer,7 on precancerous lesion of stomach and 3 on lymphoma of stomach. Meta analysis was used to sum up the odds ratios (OR) of these studies. RESULTS: H. pylori vs gastric cancer (intestinal and diffuse type): the odds ratio from the fixed effect model is 3.0016 (95% CI: 2.4197-3.7234, P【0.001). H. pylori vs precancerous lesion of stomach: a random effect model was used to calculate the summary odds ratio and its value is 2.5635 (95% CI: 1.8477-3.5566, P【0.01). H. pylori vs lymphoma of stomach: though the quantity of literature is too small to make Meta analysis, the data of these 3 studies show that lymphoma of stomach is highly associated with H. pylori infections. CONCLUSION: Since it had been revealed that H. pylori infection pre-exists in gastric carcinoma and precancerous lesions, the results of Meta analysis present a strong evidence to support the conclusion that H. pylori infection is a risk factor for gastric carcinoma. 展开更多
关键词 Helicobacter pylori Case-Control Studies Helicobacter Infections Humans Research Support Non-U.S. Gov't Stomach Neoplasms
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Persistence and clearance of viral RNA in 2019 novel coronavirus disease rehabilitation patients 被引量:67
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作者 Yun Ling Shui-Bao xu +13 位作者 Yi-Xiao Lin Di Tian Zhao-Qin Zhu Fa-Hui Dai fan Wu Zhi-Gang Song Wei Huang Jun Chen Bi-Jie Hu Sheng Wang En-Qiang Mao Lei Zhu Wen-Hong Zhang Hong-Zhou Lu 《Chinese Medical Journal》 SCIE CAS CSCD 2020年第9期1039-1043,共5页
Background:A patient’s infectivity is determined by the presence of the virus in different body fluids,secretions,and excreta.The persistence and clearance of viral RNA from different specimens of patients with 2019 ... Background:A patient’s infectivity is determined by the presence of the virus in different body fluids,secretions,and excreta.The persistence and clearance of viral RNA from different specimens of patients with 2019 novel coronavirus disease(COVID-19)remain unclear.This study analyzed the clearance time and factors influencing 2019 novel coronavirus(2019-nCoV)RNA in different samples from patients with COVID-19,providing further evidence to improve the management of patients during convalescence.Methods:The clinical data and laboratory test results of convalescent patients with COVID-19 who were admitted to from January 20,2020 to February 10,2020 were collected retrospectively.The reverse transcription polymerase chain reaction(RT-PCR)results for patients’oropharyngeal swab,stool,urine,and serum samples were collected and analyzed.Convalescent patients refer to recovered non-febrile patients without respiratory symptoms who had two successive(minimum 24 h sampling interval)negative RT-PCR results for viral RNA from oropharyngeal swabs.The effects of cluster of differentiation 4(CD4)+T lymphocytes,inflammatory indicators,and glucocorticoid treatment on viral nucleic acid clearance were analyzed.Results:In the 292 confirmed cases,66 patients recovered after treatment and were included in our study.In total,28(42.4%)women and 38 men(57.6%)with a median age of 44.0(34.0-62.0)years were analyzed.After in-hospital treatment,patients’inflammatory indicators decreased with improved clinical condition.The median time from the onset of symptoms to first negative RT-PCR results for oropharyngeal swabs in convalescent patients was 9.5(6.0-11.0)days.By February 10,2020,11 convalescent patients(16.7%)still tested positive for viral RNA from stool specimens and the other 55 patients’stool specimens were negative for 2019-nCoV following a median duration of 11.0(9.0-16.0)days after symptom onset.Among these 55 patients,43 had a longer duration until stool specimens were negative for viral RNA than for throat swabs,with 展开更多
关键词 COVID-19 2019-nCoV Nucleic acid detection GLUCOCORTICOID
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The Global Boundary Stratotype Section and Point (GSSP) for the base of the Hirnantian Stage (the uppermost of the Ordovician System) 被引量:67
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作者 xu Chen Jiayu Rong +7 位作者 Junxuan fan Renbin Zhan Charles E. Mitchell David A. T. Harper Michael J. Melchin Ping'an Peng Stan C. Finney Xiaofeng Wang 《Episodes》 SCIE 2006年第3期183-196,共14页
The Global boundary Stratotype Section and Point (GSSP) for the base of the Hirnantian Stage (the uppermost of the Ordovician System) is defined at a point 0.39m below the base of the Kuanyinchiao Bed in the Wangj... The Global boundary Stratotype Section and Point (GSSP) for the base of the Hirnantian Stage (the uppermost of the Ordovician System) is defined at a point 0.39m below the base of the Kuanyinchiao Bed in the Wangjiawan North section. The section is located near Wangjiawan village, 42 km north of Yichang city (western Hubei, China), at 30° 58′56″N and 111° 25′10″E. The GSSP level coincides with the first appearance of the graptolite species Normalograptus extraordinarius (Sobolevskaya). Secondary markers include the onset of a positive carbon-isotope excursion, and a slightly earlier first appearance of Normalograptus ojsuensis ( Koren and Mikhailova ). The Wangjiawan North section possesses continuity of sedimentation and biozonation with completeness of exposures, abundant and well-preserved graptolites and shelly fossils, i. e. the Hirnantia- Dalmanitina shelly fauna which is a key element for recognition of the Hirnantian Stage. The Wangjiawan North, South and Riverside sections possess favorable facies and widespread correlation potential, are free from structure complication, metamorphism and other alteration, and have good accessibility. The Riverside section in particular possesses amenability to isotopic age determination. The beginning of the Hirnantian was followed by a global episode of a major extinction event, which happened in the Diceratograptus mirus Subzone. The proposal was voted by the International Subcommission on Ordovician Stratigraphy in October, 2004, approved by the International Commission on Stratigraphy in February, 2006, and ratified by the International Union of Geological Sciences in May, 2006. 展开更多
关键词 全球界线层型剖面和节点 奥陶纪 GSSP 地层学
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ERAS理念下踝关节骨折诊疗方案优化的专家共识 被引量:64
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作者 白求恩公益基金会创伤骨科专业委员会 中国医疗保健国际交流促进会加速康复外科学分会创伤骨科学组 +32 位作者 李庭 孙志坚 柴益民 张堃 东靖明 孙旭 周雁 赵霞 米萌 肖鸿鹄 王京 翟建坡 王倩 李旭 高志强 彭贵凌 王爱国 刘利民 胡三保 王剑 芮云峰 吴新宝 余斌 裴福兴 田伟 高鹏 刘璠 姜保国 唐佩福 王满宜 李宁 张英泽 邱贵兴 《中华骨与关节外科杂志》 2019年第1期3-12,共10页
踝关节骨折是创伤骨科常见骨折之一。通过引入加速康复外科(enhanced recovery after surgery,ERAS)理念,对围手术期处理措施进行全面优化,可以进一步提高患者诊疗效果。为规范ERAS临床路径在踝关节骨折中的应用,基于前期研究经验,以循... 踝关节骨折是创伤骨科常见骨折之一。通过引入加速康复外科(enhanced recovery after surgery,ERAS)理念,对围手术期处理措施进行全面优化,可以进一步提高患者诊疗效果。为规范ERAS临床路径在踝关节骨折中的应用,基于前期研究经验,以循证医学证据为依据,经过全国专家组反复讨论,编制该专家共识,供全国创伤骨科医师在临床工作中参考。该共识适用于所有进行择期手术治疗的成人新鲜踝关节骨折患者。共识共包含25条推荐意见,就踝关节骨折患者急诊处理、术前准备、术中处理以及术后恢复进行了全面介绍。 展开更多
关键词 加速康复外科 踝关节骨折 专家共识 围手术期处理
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智能化采煤工作面分类、分级评价指标体系 被引量:63
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作者 王国法 徐亚军 +9 位作者 孟祥军 范京道 吴群英 任怀伟 庞义辉 杜毅博 赵国瑞 李明忠 马英 张金虎 《煤炭学报》 EI CAS CSCD 北大核心 2020年第9期3033-3044,共12页
针对我国智能化工作面尚没有统一标准,无法对煤矿智能化建设和发展水平进行科学合理定量评价问题,开展了智能化工作面分类、分级与评价指标体系研究,给出了智能化采煤工作面定义,建立了智能化工作面指标体系数学模型,提出了智能化工作... 针对我国智能化工作面尚没有统一标准,无法对煤矿智能化建设和发展水平进行科学合理定量评价问题,开展了智能化工作面分类、分级与评价指标体系研究,给出了智能化采煤工作面定义,建立了智能化工作面指标体系数学模型,提出了智能化工作面分类、分级评价指标体系与评价方法,开发了智能化采煤工作面分类、分级评价软件,结合具体案例,验证了评价方法与评价结果的科学合理性。首先对智能化采煤工作面、工作面智能集控中心、智能化开采模式等术语进行定义,提出智能化采煤工作面一般技术要求与系统配套条件,根据工作面煤层厚度、赋存条件、采煤方法和开采技术参数对智能化采煤工作面开采模式进行分类,将智能化采煤工作面分为薄煤层和中厚煤层智能化有人巡视无人操作、大采高煤层人-机-环智能耦合高效综采和综放工作面智能化操控与人工干预辅助放煤3种模式。然后以煤层赋存条件为基本指标、开采技术参数为参考指标,建立智能化采煤工作面分类评价指标体系,将采煤工作面煤层开采条件分为Ⅰ类、Ⅱ类、Ⅲ类;将智能化采煤工作面系统细分为智能割煤、智能支护、智能运输、智能控制、网络通讯、智能视频、智能喷雾、智能供液、智能巡检、智能供电、工作面照明、工作面语音、通风防灭火和安全监测14个子系统,针对不同类别工作面生产条件,分别对其设备性能达标条件和设备运行工况达标条件进行评价,建立适用于不同类别的智能化采煤工作面分级评价指标体系,将智能化采煤工作面分为高级、中级、初级3个级别,综合评价智能化工作面水平。最后以具体的采煤工作面为例,对智能化工作面相关指标进行具体解析,验证评价指标体系与评价方法的合理性与科学性。 展开更多
关键词 智能化采煤工作面 分类 分级 评价指标体系 技术条件
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Efficacy of cattle encephalon glycoside and ignotin in patients with acute cerebral infarction: a randomized, double-blind, parallel-group, placebo-controlled study 被引量:60
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作者 Hui Zhang Chuan-Ling Li +11 位作者 Feng Wan Su-Juan Wang Xiu-E Wei Yan-Lei Hao Hui-Lin Leng Jia-Min Li Zhong-Rui Yan Bao-Jun Wang Ren-Shi xu Ting-Min Yu Li-Chun Zhou Dong-Sheng fan 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第7期1266-1273,共8页
Cattle encephalon glycoside and ignotin(CEGI)injection is a compound preparation formed by a combination of muscle extract from hea lthy rabbits and brain gangliosides from cattle,and it is generally used as a neuropr... Cattle encephalon glycoside and ignotin(CEGI)injection is a compound preparation formed by a combination of muscle extract from hea lthy rabbits and brain gangliosides from cattle,and it is generally used as a neuroprotectant in the treatment of central and peripheral nerve injuries.However,there is still a need for high-level clinical evidence from large samples to support the use of CEGI.We therefore carried out a prospective,multicenter,randomized,double-blind,parallel-group,placebo-controlled study in which we recruited 319 patients with acute cerebral infarction from 16 centers in China from October 2013 to May 2016.The patients were randomized at a 3:1 ratio into CEGI(n=239;155 male,84 female;61.2±9.2 years old)and placebo(n=80;46 male,34 female;63.2±8.28 years old)groups.All patients were given standard care once daily for 14 days,including a 200 mg aspirin enteric-coated tablet and 20 mg atorvastatin calcium,both taken orally,and intravenous infusion of 250–500 mL 0.9%sodium chloride containing 40 mg sodium tanshinone IIA sulfonate.Based on conventional treatment,patients in the CEGI and placebo groups were given 12 mL CEGI or 12 mL sterile water,respectively,in an intravenous drip of 250 mL 0.9%sodium chloride(2 mL/min)once daily for 14 days.According to baseline National Institutes of Health Stroke Scale scores,patients in the two groups were divided into mild and moderate subgroups.Based on the modified Rankin Scale results,the rate of patients with good outcomes in the CEGI group was higher than that in the placebo group,and the rate of disability in the CEGI group was lower than that in the placebo group on day 90 after treatment.In the CEGI group,neurological deficits were decreased on days 14 and 90 after treatment,as measured by the National Institutes of Health Stroke Scale and the Barthel Index.Subgroup analysis revealed that CEGI led to more significant improvements in moderate stroke patients.No drug-related adverse events occurred in the CEGI or placebo groups.In conclusion,CEGI may be a 展开更多
关键词 acute cerebral infarction Barthel Index cattle encephalon glycoside and ignotin modified Rankin Scale National Institutes of Health Stroke Scale NEUROPROTECTANTS recovery rate stroke
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