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Distribution and Formation Causes of PM_(2.5) and O_(3) Double High Pollution Events in China during 2013–20
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作者 Zhixuan TONG Yingying YAN +6 位作者 Shaofei KONG Jintai LIN Nan CHEN Bo ZHU Jing MA Tianliang ZHAO Shihua QI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1235-1250,I0004-I0021,共34页
Fine particulate matter(PM_(2.5))and ozone(O_(3))double high pollution(DHP)events have occurred frequently over China in recent years,but their causes are not completely clear.In this study,the spatiotemporal distribu... Fine particulate matter(PM_(2.5))and ozone(O_(3))double high pollution(DHP)events have occurred frequently over China in recent years,but their causes are not completely clear.In this study,the spatiotemporal distribution of DHP events in China during 2013–20 is analyzed.The synoptic types affecting DHP events are identified with the Lamb–Jenkinson circulation classification method.The meteorological and chemical causes of DHP events controlled by the main synoptic types are further investigated.Results show that DHP events(1655 in total for China during 2013–20)mainly occur over the North China Plain,Yangtze River Delta,Pearl River Delta,Sichuan Basin,and Central China.The occurrence frequency increases by 5.1%during 2013–15,and then decreases by 56.1%during 2015–20.The main circulation types of DHP events are“cyclone”and“anticyclone”,accounting for over 40%of all DHP events over five main polluted regions in China,followed by southerly or easterly flat airflow types,like“southeast”,“southwest”,and“east”.Compared with non-DHP events,DHP events are characterized by static or weak wind,high temperature(20.9℃ versus 23.1℃)and low humidity(70.0%versus 64.9%).The diurnal cycles of meteorological conditions cause PM_(2.5)(0300–1200 LST,Local Standard Time=UTC+8 hours)and O_(3)(1500–2100 LST)to exceed the national standards at different periods of the DHP day.Three pollutant conversion indices further indicate the rapid secondary conversions during DHP events,and thus the concentrations of NO_(2),SO_(2) and volatile organic compounds decrease by 13.1%,4.7%and 4.4%,respectively.The results of this study can be informative for future decisions on the management of DHP events. 展开更多
关键词 double high pollution events PM_(2.5) OZONE spatiotemporal distribution meteorological causes chemical composition characteristics
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基于Transformer的矿井内因火灾时间序列预测方法 被引量:1
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作者 王树斌 王旭 +1 位作者 闫世平 王珂 《工矿自动化》 CSCD 北大核心 2024年第3期65-70,91,共7页
传统的基于机器学习的矿井内因火灾预测方法尽管具备一定的预测能力,然而在处理复杂的多变量数据时不能有效捕捉数据间的全局依赖关系,导致预测精度较低。针对上述问题,提出了一种基于Transformer的矿井内因火灾时间序列预测方法。首先... 传统的基于机器学习的矿井内因火灾预测方法尽管具备一定的预测能力,然而在处理复杂的多变量数据时不能有效捕捉数据间的全局依赖关系,导致预测精度较低。针对上述问题,提出了一种基于Transformer的矿井内因火灾时间序列预测方法。首先,采用Hampel滤波器和拉格朗日插值法对数据进行异常值检测和缺失值填补。然后,利用Transformer的自注意力机制对时间序列数据进行特征提取及趋势预测。最后,通过调节滑动窗口的大小与步长,在不同的时间步长和预测长度下对模型进行不同时间维度的训练。结合气体分析法将矿井火灾产生的标志性气体(CO,O_(2),N_(2),CO_(2),C_(2)H_(2),C_(2)H4,C_(2)H_(6))作为模型输入变量,其中CO作为模型输出的目标变量,O_(2),N_(2),CO_(2),C_(2)H_(2),C_(2)H4,C_(2)H_(6)作为模型输入的协变量。选取陕煤集团柠条塔煤矿S1206回风隅角火灾预警的束管数据进行实验验证,结果表明:①对CO进行单变量预测和多变量预测,多变量预测相比单变量预测有着更高的预测精度,说明多变量预测能通过捕捉序列间的相关性提高模型的预测精度。②当时间步长固定时,基于Transformer的矿井内因火灾预测模型的预测精度随着预测长度的增加而下降。当预测长度固定时,模型的预测精度随时间步长增加而提高。③Transformer算法的预测精度较长短时记忆(LSTM)算法和循环神经网络(RNN)算法分别提高了7.1%~12.6%和20.9%~24.9%。 展开更多
关键词 矿井内因火灾 TRaNSforMER 时间序列 标志性气体 自注意力机制
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Instructions for Manuscript Preparation
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《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期I0003-I0003,共1页
Plasma Science and Technology (PST) journal assists in advancing plasma science and technology by reporting important,novel,helpful and thought-provoking progress in this strongly multidisciplinary and interdisciplina... Plasma Science and Technology (PST) journal assists in advancing plasma science and technology by reporting important,novel,helpful and thought-provoking progress in this strongly multidisciplinary and interdisciplinary field,in a timely manner. 展开更多
关键词 JOURNaL timely helpful
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Analysis of the causes of primary revision after unicompartmental knee arthroplasty: A case series
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作者 Jin-Long Zhao Xiao Jin +5 位作者 He-Tao Huang Wei-Yi Yang Jia-Hui Li Ming-Hui Luo Jun Liu Jian-Ke Pan 《World Journal of Clinical Cases》 SCIE 2024年第9期1560-1568,共9页
BACKGROUND Unicompartmental knee arthroplasty(UKA)has great advantages in the treatment of unicompartmental knee osteoarthritis,but its revision rate is higher than that of total knee arthroplasty.AIM To summarize and... BACKGROUND Unicompartmental knee arthroplasty(UKA)has great advantages in the treatment of unicompartmental knee osteoarthritis,but its revision rate is higher than that of total knee arthroplasty.AIM To summarize and analyse the causes of revision after UKA.METHODS This is a retrospective case series study in which the reasons for the first revision after UKA are summarized.We analysed the clinical symptoms,medical histories,laboratory test results,imaging examination results and treatment processes of the patients who underwent revision and summarized the reasons for primary revision after UKA.RESULTS A total of 13 patients,including 3 males and 10 females,underwent revision surgery after UKA.The average age of the included patients was 67.62 years.The prosthesis was used for 3 d to 72 months.The main reasons for revision after UKA were improper suturing of the surgical opening(1 patient),osteophytes(2 patients),intra-articular loose bodies(2 patients),tibial prosthesis loosening(2 patients),rheumatoid arthritis(1 patient),gasket dislocation(3 patients),anterior cruciate ligament injury(1 patient),and medial collateral ligament injury with residual bone cement(1 patient).CONCLUSION The causes of primary revision after UKA were gasket dislocation,osteophytes,intra-articular loose bodies and tibial prosthesis loosening.Avoidance of these factors may greatly reduce the rate of revision after UKA,improve patient satisfaction and reduce medical burden. 展开更多
关键词 Unicompartmental knee arthroplasty Total knee arthroplasty causeS REVISION Case series
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Environmental and Climate Justice in Palestine
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作者 Jad Isaac Jane Hilal 《American Journal of Climate Change》 2024年第2期251-280,共30页
To have a clean, safe, and functional environment is not only essential for the purpose of preservation, but also imperative for safeguarding the most fundamental of human rights. Resolution 45/94 of the United Nation... To have a clean, safe, and functional environment is not only essential for the purpose of preservation, but also imperative for safeguarding the most fundamental of human rights. Resolution 45/94 of the United Nations (UN) General Assembly also stresses and acknowledges that: “all individuals are entitled to live in an environment adequate for their health and wellbeing” (United Nations Digital Library System, 1991). Environmental and climate justice, which: “emerged in the context of the local environmental struggles of directly oppressed groups”, is a global movement dedicated to ensuring equal protection of people’s human rights (i.e., water, health, life, etc.) in the face of the climate crisis. Moreover, health, environment and human rights are part of the 2030 agenda (in particular, SDG 1, SDG 5, SDG 6, SDG 7, SDG 13, SDG 16, SDG 17). Individually, both environmental and climate justice are rooted in an intersectional outlook, by which they highlight the common threads between communities and the people’s inclusion, irrespective of race, class, or gender, in the pursuit of justice. On the other hand, they recognise and acknowledge the role and consequences of climate change in economic, social, and political dimensions;thus, drawing emphasis on the rights of people under the emerging inequities. In the case of Palestine, the Palestinian community is increasingly becoming vulnerable to these effects and the resulting inequalities of climate change. This vulnerability stems from: 1) The right to life;clean WASH;equitable work opportunities;access to resources;and free movement;are all examples of human rights that the Israeli colonial regime infringes upon;2) Infrastructure is essential for climate adaptation: 61% of the West Bank is ultimately barred from building infrastructure (B’Tselem, 2019) and Gaza Strip has major gaps in infrastructure due to intentional destruction by Israel;3) Palestinian deprivation of the sovereign right to natural resources by Israel;4) Apartheid system in water accessibility: Israeli water usage per person is over three times higher than that of Palestinians (their usage is under the WHO recommended minimum per day) (B’Tselem, 2023);and 5) Violent settler attacks. In 2022 alone, the Applied Research Institute-Jerusalem (ARIJ) recorded 1527 settler attacks that targeted land, properties, livestock, agriculture and even Palestinian civilians. The ongoing neglect of these concerns and the persistent colonization of Palestine by Israel unequivocally and unwaveringly affect the human rights of Palestinians. The power dynamics at play especially hamper the Palestinian ability to exercise and fulfill their inalienable human rights and to tackle the obstacles to justice in their environment. 展开更多
关键词 Environmental Degradation Climate Change Environmental and Climate justice Human Rights causes and Solution
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The Impacts and Causes of Land Fragmentation on Farm Productivity: Case Review of East African Countries
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作者 Joseph Mayindo Mayele Jacob B. Kolleh Joel Emmanuel Saburi 《Open Journal of Ecology》 2024年第5期455-482,共28页
This report provides an overall assessment of land fragmentation problems in East Africa. Many parts of East Africa have become highly fragmented, putting development systems and activities in these areas at risk of c... This report provides an overall assessment of land fragmentation problems in East Africa. Many parts of East Africa have become highly fragmented, putting development systems and activities in these areas at risk of complete collapse. Land fragmentation occurs when land gets converted for agriculture, industrialization, or urbanization, invaded by non-local plants, or enclosed for individual use and by subdividing farmlands into subsequent smaller units called parcels with varying average farm sizes. Fragmentation results from inappropriate agricultural development processes and ineffective land use planning that fails to recognize how farmland is used, and the importance of its interconnected areas. Insecurity of tenure and resource rights are key factors in making this possible. Land fragmentation is one of the key reasons why the ability of most resources in East Africa becomes scarcer, and those remaining become “privatized” by more powerful community members—keen to maintain their access to them. Such individualistic attitudes are new and disadvantage the poorest even further by affecting the traditional customary safety nets and agricultural outputs. Neither the government nor customary governance systems effectively protect resource access for the poorest. This review summary report identifies the key causes, measures, and implications, government interventions, and the common remedies to land fragmentation problems in the East African Countries of Kenya, Uganda, Rwanda, and Tanzania including neighboring Ethiopia, and the Sudan. The findings indicated from 2005 to 2015, the population kept increasing for all the named countries in East Africa with Rwanda and Uganda having a substantial increase in population density. The study review further explores the trend in the performance of agriculture by average farm sizes within the intervals of five years by highlighting their strong linkages and found that the average farm size has declined drastically, especially for Kenya. This can only mean that small farms kept becoming smaller and smaller and that there were more small-scale farmers. The results further depicted that the major and commonly cultivated food crops among the East African countries include maize, sorghum, rice, cassava, sweet potatoes, bananas, Irish potatoes, beans, peas, etc., with maize yields (Mt/ha) in 2003 for Uganda being the highest (1.79 Mt/ha) and the lowest in Rwanda (0.77 Mt/ha) respectively. Therefore, from the review results, recommendations are being made as to how the negative impacts of land fragmentation on agricultural productivity can be reduced or mitigated. One way is by community sensitization and awareness about the importance of land consolidation and its proposition on farm productivity. 展开更多
关键词 Land Fragmentation Land Consolidation Farm Productivity INDUSTRIaLIZaTION Impacts causeS average Farm Size Population East africa
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Eternal Climate Change Patterns and the Causes and Countermeasures of Global Climate Change
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作者 Cuixiang Zhong 《Journal of Environmental Science and Engineering(B)》 2024年第1期9-20,共12页
It is an objective fact that the weather is unpredictable.Even the famous meteorologist,Academician Chu Ko Chen,has only a partial understanding of the changing laws of wind and rain.Even though ancient people summari... It is an objective fact that the weather is unpredictable.Even the famous meteorologist,Academician Chu Ko Chen,has only a partial understanding of the changing laws of wind and rain.Even though ancient people summarized the 24 solar terms by observing the annual activities of the sun for a long time,because they ignored the impact of the activities of the moon on the Earth’s climate change on a small scale,the 24 solar terms they summarized often could not accurately predict the change of the Earth’s climate.Therefore,the author studied the influence of lunar activities on the Earth’s climate change,finds out the law of the influence of lunar activities on the Earth’s climate change on a small scale,and summarizes the eternal climate change pattern determined by the activities of the sun and the moon.In addition,the author also reveals the causes and countermeasures of global warming and the frequent occurrence of extreme weather as well as environmental change. 展开更多
关键词 Eternal climate change patterns global warming extreme weather abrupt environmental changes causeS countermeasures.
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Turning Dreams Into Reality China is committed to helping African countries to build their space capability
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作者 XIA YUANYUAN 《ChinAfrica》 2024年第5期22-24,共3页
An important feature of China developing its aerospace industry is its insistence on self-reliance and independent innovation,because China firmly believes that aerospace is a hi-tech industry and high core technologi... An important feature of China developing its aerospace industry is its insistence on self-reliance and independent innovation,because China firmly believes that aerospace is a hi-tech industry and high core technologies cannot be bought.Only by mastering core technologies can China firmly grasp the initiative in development. 展开更多
关键词 firmly industry helpING
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Omadacycline for the treatment of Legionella pneumophila pneumonia caused by drowning:a case report
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作者 Xiao Lu Wenqi Qi +3 位作者 Haizhen Wang Zhongjun Zheng Libing Jiang Shanxiang Xu 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2023年第6期481-483,共3页
Drowning is a major cause of preventable death and pathology worldwide.Every year,more than 295,000people die from accidental drowning.Ninety percent of accidental drowning deaths occur in low-and middleincome countri... Drowning is a major cause of preventable death and pathology worldwide.Every year,more than 295,000people die from accidental drowning.Ninety percent of accidental drowning deaths occur in low-and middleincome countries,and nearly half occur in people under the age of 25. 展开更多
关键词 DEaTH PNEUMONIa cause
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Knowledge-enriched joint-learning model for implicit emotion cause extraction
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作者 Chenghao Wu Shumin Shi +1 位作者 Jiaxing Hu Heyan Huang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第1期118-128,共11页
Emotion cause extraction(ECE)task that aims at extracting potential trigger events of certain emotions has attracted extensive attention recently.However,current work neglects the implicit emotion expressed without an... Emotion cause extraction(ECE)task that aims at extracting potential trigger events of certain emotions has attracted extensive attention recently.However,current work neglects the implicit emotion expressed without any explicit emotional keywords,which appears more frequently in application scenarios.The lack of explicit emotion information makes it extremely hard to extract emotion causes only with the local context.Moreover,an entire event is usually across multiple clauses,while existing work merely extracts cause events at clause level and cannot effectively capture complete cause event information.To address these issues,the events are first redefined at the tuple level and a span-based tuple-level algorithm is proposed to extract events from different clauses.Based on it,a corpus for implicit emotion cause extraction that tries to extract causes of implicit emotions is constructed.The authors propose a knowledge-enriched jointlearning model of implicit emotion recognition and implicit emotion cause extraction tasks(KJ-IECE),which leverages commonsense knowledge from ConceptNet and NRC_VAD to better capture connections between emotion and corresponding cause events.Experiments on both implicit and explicit emotion cause extraction datasets demonstrate the effectiveness of the proposed model. 展开更多
关键词 emotion cause extraction external knowledge fusion implicit emotion recognition joint learning
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The Study for the Causes of Pragmatic Failure
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作者 唐晓虹 严艳 《海外英语》 2012年第9X期224-226,共3页
This paper,based on the questionnaire,deduces the causes of pragmatic failure which are summarized into four:The different value orientation between the two cultures,consisting individualism versus collectivism,power ... This paper,based on the questionnaire,deduces the causes of pragmatic failure which are summarized into four:The different value orientation between the two cultures,consisting individualism versus collectivism,power distance,connotation versus denotation,and orientation towards time,negative transfer of equivalent structures and behaviors,insufficient or improper teaching and the scarcity of universal knowledge for communication. 展开更多
关键词 PRaGMaTIC FaILURE cause value ORIENTaTION TRaNSFER
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基于Reason模型的SIF-Q260型电子小肠镜故障原因分析
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作者 翁飞 李相林 +1 位作者 程时栋 潘振宇 《中国医学装备》 2024年第2期189-192,共4页
根据武汉大学中南医院内窥镜中心SIF-Q260型小肠镜故障率高且维修成本高的情况,应用Reason模型,从环境影响、不安全监督、不安全行为前兆及不安全行为4个层面分析造成SIF-Q260小肠镜故障的原因,针对各个层面故障原因,从定期培训以规范... 根据武汉大学中南医院内窥镜中心SIF-Q260型小肠镜故障率高且维修成本高的情况,应用Reason模型,从环境影响、不安全监督、不安全行为前兆及不安全行为4个层面分析造成SIF-Q260小肠镜故障的原因,针对各个层面故障原因,从定期培训以规范内窥镜的洗消及使用、设置专人管理内窥镜并定期对内窥镜使用洗消的规范性进行监督及评价、完善内窥镜监管系统3方面拟定改进措施,堵住系统“漏洞”,为内窥镜质量控制措施的制定提供依据,可预防和减少内窥镜故障的发生。 展开更多
关键词 电子内窥镜 Reason模型 故障 原因分析 质量控制
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低强度激光联合口腔正畸对牙周病致前牙移位患者疼痛及龈沟液ALP、AST、sICAM-1水平的影响
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作者 王冠超 马俐丽 +2 位作者 李丹 陈超 孙强 《川北医学院学报》 CAS 2024年第7期892-895,共4页
目的:探讨低强度激光联合口腔正畸对牙周病致前牙移位患者疼痛及龈沟液中碱性磷酸酶(ALP)、天门冬氨酸氨基转移酶(AST)、可溶性细胞间粘附分子-1(sICAM-1)水平的影响。方法:选取89例牙周病致前牙移位患者为研究对象,根据治疗方式不同分... 目的:探讨低强度激光联合口腔正畸对牙周病致前牙移位患者疼痛及龈沟液中碱性磷酸酶(ALP)、天门冬氨酸氨基转移酶(AST)、可溶性细胞间粘附分子-1(sICAM-1)水平的影响。方法:选取89例牙周病致前牙移位患者为研究对象,根据治疗方式不同分为对照组(n=44)与研究组(n=45)。对照组患者接受口腔正畸治疗;研究组患者在对照组基础上联合低强度激光治疗,两组患者疗程均为3个月。比较两组患者各时间点疼痛情况[视觉模拟评分(VAS)]、牙齿移动距离、牙齿回缩速度、牙齿松动度及龈沟液中ALP、AST、sICAM-1水平。结果:治疗后2、4、24 h及3 d,研究组患者VAS评分均低于对照组(P<0.05)。治疗后7、14、28 d及3个月,研究组患者牙齿移动距离均高于对照组(P<0.05)。治疗后7、14、28 d,研究组患者牙齿回缩速度均高于对照组(P<0.05)。治疗后3个月,两组患者龈沟液中ALP、AST、sICAM-1表达水平均升高,且研究组低于对照组(P<0.05)。结论:在口腔正畸的基础上联合低强度激光治疗有利于加速牙周病致前牙移位牙齿移动,可有效缓解疼痛及牙周炎性反应。 展开更多
关键词 低强度激光 口腔正畸 牙周病致前牙移位 疼痛 炎性反应
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基于Apriori算法的煤矿安全事故分析
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作者 景国勋 秦洪利 蒋方 《安全与环境学报》 CAS CSCD 北大核心 2024年第6期2313-2320,共8页
为分析煤矿事故报告中的危险致因因素,统计分析了2018—2022年全国煤矿事故报告数据,采用Apriori关联规则算法,并利用Gephi进行关联规则可视化,探究各个致因之间的复杂关系。首先对数据进行预处理,计算词频-逆向文件频率(Term Frequency... 为分析煤矿事故报告中的危险致因因素,统计分析了2018—2022年全国煤矿事故报告数据,采用Apriori关联规则算法,并利用Gephi进行关联规则可视化,探究各个致因之间的复杂关系。首先对数据进行预处理,计算词频-逆向文件频率(Term Frequency-Inverse Document Frequency, TF-IDF),提取了78个煤矿事故致因因素,其中人因层包括31个因素,设备层包括9个因素,管理层包括31个因素,环境层包括7个因素;然后,经过关联规则挖掘算法,得到了585条关联规则,绘制了其支持度、置信度和提升度的散点图;最后,根据Gephi生成的事故致因复杂网络图,分别分析了高支持度、高置信度和高提升度关联规则致因因素。结果表明:基于Apriori算法的煤矿事故致因分析,得到了人因层、管理层、设备层和环境层4个方面的关键致因因素;对煤矿关键致因因素进行直观、多视图的展现,有助于提高煤矿安全管理水平。 展开更多
关键词 安全工程 煤矿事故 事故原因 aPRIORI算法 复杂网络图
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高校实验室PAR事故致因模型构建及应用
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作者 阳富强 黄宝娇 +1 位作者 葛樊亮 黄宗侯 《实验室研究与探索》 CAS 北大核心 2024年第7期249-253,共5页
高校实验室是集聚和培养优秀专业人才、开展高水平科学研究的重要基地,但目前仍面临较多安全管理难题。现以“中科院某研究所高压反应釜爆炸事故”为例,采用PAR事故致因模型开展高校实验室安全管理研究,以安全感知—安全分析—安全应答(... 高校实验室是集聚和培养优秀专业人才、开展高水平科学研究的重要基地,但目前仍面临较多安全管理难题。现以“中科院某研究所高压反应釜爆炸事故”为例,采用PAR事故致因模型开展高校实验室安全管理研究,以安全感知—安全分析—安全应答(PAR)为节点,对实验室建设与管理处、中心实验室、实验室操作主体3个层面进行分析。研究表明,PAR模型能充分发挥安全信息的交流作用,从宏观、中观、微观3个层面进行事故致因分析,为完善实验室事故分析体系等提供有效支撑。本研究对高校实验室安全管理的安全信息分析和风险防控提供参考,对实验室安全管理有一定理论指导意义。 展开更多
关键词 PaR事故致因模型 安全信息 高校实验室 安全管理
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采用STAMP-24Model的多组织事故分析
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作者 曾明荣 秦永莹 +2 位作者 刘小航 栗婧 尚长岭 《安全与环境学报》 CAS CSCD 北大核心 2024年第7期2741-2750,共10页
安全生产事故往往由多组织交互、多因素耦合造成,事故原因涉及多个组织。为预防和遏制多组织生产安全事故的发生,基于系统理论事故建模与过程模型(Systems-Theory Accident Modeling and Process,STAMP)、24Model,构建一种用于多组织事... 安全生产事故往往由多组织交互、多因素耦合造成,事故原因涉及多个组织。为预防和遏制多组织生产安全事故的发生,基于系统理论事故建模与过程模型(Systems-Theory Accident Modeling and Process,STAMP)、24Model,构建一种用于多组织事故分析的方法,并以青岛石油爆炸事故为例进行事故原因分析。结果显示:STAMP-24Model可以分组织,分层次且有效、全面、详细地分析涉及多个组织的事故原因,探究多组织之间的交互关系;对事故进行动态演化分析,可得到各组织不安全动作耦合关系与形成的事故失效链及管控失效路径,进而为预防多组织事故提供思路和参考。 展开更多
关键词 安全工程 系统理论事故建模与过程模型(STaMP) 24Model 多组织事故 原因分析
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An Extreme Monsoonal Heavy Rainfall Event over Inland South China in June 2022: A Synoptic Causes Analysis 被引量:1
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作者 邓文剑 任鹏飞 +2 位作者 张东 孙宇 吴乃庚 《Journal of Tropical Meteorology》 SCIE 2023年第1期16-25,共10页
An extreme monsoonal heavy rainfall event lasted for nine days and recurred in the interior of northern south China from June 13 to 21, 2022. Using regional meteorological stations and ERA5 reanalysis data, the causes... An extreme monsoonal heavy rainfall event lasted for nine days and recurred in the interior of northern south China from June 13 to 21, 2022. Using regional meteorological stations and ERA5 reanalysis data, the causes of this extreme monsoonal rainfall event in south China were analyzed and diagnosed. The results are shown as follows. A dominant South Asian high tended to be stable near the Qinghai-Tibet Plateau, providing favorable upper-level dispersion conditions for the occurrence of heavy rainfall in south China. A western Pacific subtropical high dominated the eastern part of the South China Sea, favoring stronger and more northward transport of water vapor to the northern part of south China at lower latitudes than normal. The continuous heavy precipitation event can be divided into two stages. The first stage(June 13-15) was the frontal heavy rainfall caused by cold air(brought by an East Asian trough)from the mid-latitudes that converged with a monsoonal airflow. The heavy rains occurred mostly in the area near a shear in front of the center of a synoptic-system-related low-level jet(SLLJ), and the jet stream and precipitation were strongest in the daytime. The second stage(June 16-21) was the warm-sector heavy rainfall caused by a South China Sea monsoonal low-level jet penetrating inland. The heavy rainfall occurred on the windward slope of the Nanling Mountains and in the northern part of a boundary layer jet(BLJ). The BLJ experienced five nighttime enhancements, corresponding well with the enhancement of the rainfall center, showing significant nighttime heavy rainfall characteristics. Finally, a conceptual diagram of inland-type warm-sector heavy rainfall in south China is summarized. 展开更多
关键词 monsoonal heavy rainfall south China low-level jet synoptic causes
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New Evidences on the Climatic Causes of the Formation of the Spring Persistent Rains over Southeastern China 被引量:8
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作者 万日金 赵兵科 吴国雄 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第6期1081-1087,共7页
The spring persistent rains(SPR)over southeastern China(SEC)are a unique synoptic and climatic phenomenon in East Asia.A former study has found that the southwesterly flow which lies on the southeastern flank of t... The spring persistent rains(SPR)over southeastern China(SEC)are a unique synoptic and climatic phenomenon in East Asia.A former study has found that the southwesterly flow which lies on the southeastern flank of the Tibetan Plateau(TP)is one of the deflected westerly flows of the TP,and it is suggested to be the direct climatic cause of SPR.This study found that the southwesterly flow is also highly correlated with the sensible heating of the southeastern TP in interannual variability,in addition to having a high correlation in seasonal variability.These facts suggest that the thermal forcing of the TP is another important climatic cause of SPR.Numerical sensitivity experiments further prove that the mechanical and thermal forcings of the TP are the climatic causes of the formation of the SPR.On the other hand,the Nanling Mountains and Wuyi Mountains(NWM)over southeastern China not only increase the SPR precipitation amount evidently,but also make the SPR rain belt move to the south by blocking the strong southwesterly flow. 展开更多
关键词 spring persistent rains climatic causes southwesterly flow the Tibet Plateau sensitivity experiments
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错误信息(Misinformation)的成因、负面影响及管控:基于国外研究的综述 被引量:1
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作者 付少雄 陈晓宇 +1 位作者 郑汉 夏苏迪 《图书馆杂志》 北大核心 2023年第5期33-43,54,共12页
鉴于国外对错误信息研究的关注日益增长而国内缺乏其相关研究综述,文章从错误信息的成因、负面影响及管控等维度系统性地回顾了国外相关研究。首先,从用户与机器角度述评了错误信息生成研究,从信息源、易感宿主、信息环境视角述评了错... 鉴于国外对错误信息研究的关注日益增长而国内缺乏其相关研究综述,文章从错误信息的成因、负面影响及管控等维度系统性地回顾了国外相关研究。首先,从用户与机器角度述评了错误信息生成研究,从信息源、易感宿主、信息环境视角述评了错误信息传播研究。其次,从用户错误认知发展、错误信息决策制定、用户行为改变方面述评了错误信息负面影响。最后,从信息平台与用户角度述评了错误信息管控研究。文章发现国外现有研究在研究情境、研究视角、研究方法与数据等方面存在局限性。为此,建议未来错误信息研究可进一步细分研究对象、分析技术的综合影响、拓展数据收集和分析方法。 展开更多
关键词 错误信息 信息成因 信息传播 负面影响 信息管控
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Population attributable risks of cigarette smoking for deaths of all causes, all cancers and other chronic diseases among adults aged 40-74 years in urban Shanghai, China 被引量:6
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作者 Ying-Ying Wang Wei Zhang +6 位作者 Hong-Lan Li Jing Gao Yu-Ting Tan Yu-Tang Gao Xiao-Ou Shu Wei Zheng Yong-Bing Xiang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2015年第1期59-65,共7页
Objective: To evaluate the population attributable risks (PARs) between cigarette smoking and deaths of all causes, all cancers, lung cancer and other chronic diseases in urban Shanghai. Methods: In total, 61,480 ... Objective: To evaluate the population attributable risks (PARs) between cigarette smoking and deaths of all causes, all cancers, lung cancer and other chronic diseases in urban Shanghai. Methods: In total, 61,480 men aged 40-74 years from 2002 to 2006 and 74,941 women aged 40-70 years from 1997 to 2000 were recruited to undergo baseline surveys in urban Shanghai, with response rates of 74.0% and 92.3%, respectively. A Cox proportional hazards regression model was used to estimate relative risks (RRs) and 95% confidence intervals (95% CIs) of deaths associated with cigarette smoking. PARs and 95 % CIs for deaths were estimated from smoking exposure rates and the estimated RRs. Results: Cigarette smoking was responsible for 23.9% (95% CI: 19.4-28.3%) and 2.4% (95% Ch 1.6- 3.2%) of all deaths in men and women, respectively, in our study population. Respiratory disease had the highest PAR in men [37.5% (95% CI: 21.5-51.6%)], followed by cancer [31.3% (95% Ch 24.6-37.7%)] and cardiovascular disease (CVD) [24.1% (95% CI: 16.7-31.2%)]. While the top three PARs were 12.7% (95% CI: 6.1-19.3%), 4.0% (95% CI: 2.4-5.6%), and 1.1% (95% CI: 0.0-2.3%), for respiratory disease, CVD, and cancer, respectively in women. For deaths of lung cancer, the PAR of smoking was 68.4% (95% CI: 58.2- 76.5%) in men. Conclusions: In urban Shanghai, 23.9% and 2.4% of all deaths in men and women could have been prevented if no people had smoked in the area. Effective control programs against cigarette smoking should be strongly advocated to reduce the increasing smoking-related death burden. 展开更多
关键词 Population attributable risk (PaR) SMOKING mortality cohort study all causes death cancer death lung cancer
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