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中国制造2025背景下电器可靠性技术教学案例设计
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作者 王海涛 王景芹 赵靖英 《中国教育技术装备》 2024年第6期61-64,共4页
“中国制造2025”为中国制造业未来10年设计顶层规划和路线图,其基本方针:质量为先、人才为本。低压电器是电力系统的核心基础零部件,低压电器产品的质量对电力系统的发展、安全运行起到至关重要的作用。培养低压电器可靠性方面的人才... “中国制造2025”为中国制造业未来10年设计顶层规划和路线图,其基本方针:质量为先、人才为本。低压电器是电力系统的核心基础零部件,低压电器产品的质量对电力系统的发展、安全运行起到至关重要的作用。培养低压电器可靠性方面的人才迫在眉睫。电器可靠性技术是电机与电器学科大三的核心专业课程,其作用和意义凸显。以可靠性抽样检查模块为例,介绍在“中国制造2025”背景下的案例设计内容及实施过程。引导学生体会、理解“中国制造2025”的基本方针——质量为先、人才为本。旨在培养学生的家国情怀、工匠精神和责任担当。 展开更多
关键词 中国制造2025 电器可靠性技术 案例设计
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职业院校劳动教育体系建构探赜——基于“中国制造2025”背景
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作者 郭金龙 《船舶职业教育》 2024年第3期77-80,共4页
“中国制造2025”战略的实施对职业岗位技能、人才培养质量等提出了更高的要求,职业教育以及职业院校学生面临着新的机遇与挑战。因此,职业院校应明确“中国制造2025”背景下劳动教育的意蕴,探究职业院校劳动教育体系建构路径,将人才培... “中国制造2025”战略的实施对职业岗位技能、人才培养质量等提出了更高的要求,职业教育以及职业院校学生面临着新的机遇与挑战。因此,职业院校应明确“中国制造2025”背景下劳动教育的意蕴,探究职业院校劳动教育体系建构路径,将人才培养与生产劳动相结合,培养学生树立正确的劳动意识,不断提升劳动素养和能力,以适应当今高端装备制造业转型升级及制造强国建设发展对人才的新需求。 展开更多
关键词 “中国制造2025 职业院校 劳动教育 体系建构
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2025年亚冬会背景下中、日、韩三国冬季运动竞争格局及趋势分析
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作者 刘林娟 刘刚 《体育科技文献通报》 2024年第1期79-82,282,共5页
以2025年第9届亚洲冬季运动会在我国哈尔滨举办为背景,以近五届冬奥会、近三届亚冬会中、日、韩三国参赛成绩和获奖项目分布为研究对象,通过文献资料、数理统计、逻辑分析等科研方法,分析主要竞争对手,有针对性地制定备战策略。研究发现... 以2025年第9届亚洲冬季运动会在我国哈尔滨举办为背景,以近五届冬奥会、近三届亚冬会中、日、韩三国参赛成绩和获奖项目分布为研究对象,通过文献资料、数理统计、逻辑分析等科研方法,分析主要竞争对手,有针对性地制定备战策略。研究发现:①在亚洲冬季运动主要开展国中,中国、日本和韩国是竞技实力相对最强的国家,长期占据冬奥会、亚冬会前三名;②在近五届冬奥会参赛历程上,中国竞技实力最强,韩国其次,日本排名第三;③在近三年亚冬会参赛历程上,日本队竞技实力最强,中国其次,韩国排名第三。中、日、韩三国在冬季项目优势项目和潜优势项目分布上既有重叠又有区别,巩固优势项目、扩大潜优势项目是取得优异成绩的关键。据此建议:中国队备战亚冬会管理部门要强化顶层设计,明确整体备战思路;吃透冰雪项目竞赛规则,把握项目制胜规律;进一步夯实群众发展基础,探索多种途径培养人才;坚持“走出去、请进来”,把训练参赛有机结合起来,开展以赛促练。 展开更多
关键词 2025 亚冬会 冬季运动 竞争格局
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Resilience effects for household food expenditure and dietary diversity in rural western China 被引量:1
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作者 Xiao Han Kaiyu Lyu +1 位作者 Fengying Nie Yuquan Chen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期384-396,共13页
A more resilient livelihood is increasingly recognized as an efficient way to improve vulnerable households’food security and optimize their dietary decisions.This study quantifies rural household resilience in weste... A more resilient livelihood is increasingly recognized as an efficient way to improve vulnerable households’food security and optimize their dietary decisions.This study quantifies rural household resilience in western China,identifies the three pillars(absorptive capacity,adaptive capacity,and transformative capacity)contribution to resilience,and then establishes the estimated Resilience Capacity Index(RCI)linked with food security and dietary diversity supported by the multiple indicator multiple cause(MIMIC)model.Results show that,despite geographical heterogeneity,the RCI consistently increased from 2015 to 2021.Households with a higher RCI inheriting better capacity to deal with risk and shocks are significantly and positively correlated with increasing food expenditure and diversifying food choices.It can be because resilient households will allocate more money to food expenditure instead of saving for livelihood uncertainty.Thus,policymakers can provide more incentives for rural households to adopt more dynamic and effective risk management strategies.This,in turn,could yield positive spillover effects by preventing human capital loss associated with dietary-related chronic diseases and mortality. 展开更多
关键词 RESILIENCE food expenditure dietary diversity china risk management
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The impact of Internet access on household dietary quality:Evidence from rural China 被引量:1
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作者 Yi Cui Qiran Zhao +1 位作者 Thomas Glauben Wei Si 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期374-383,共10页
Over the past few decades,the Internet has rapidly diffused across China.The spread of the Internet has had a profound economic and social impact on Chinese rural areas.Existing research shows that Internet access sig... Over the past few decades,the Internet has rapidly diffused across China.The spread of the Internet has had a profound economic and social impact on Chinese rural areas.Existing research shows that Internet access significantly impacts agricultural production and improves smallholder farmers’income.Beyond these,the Internet can affect other dimensions of social welfare.However,research about the impact of Internet access on dietary quality in rural China remains scarce.This study utilizes multi-period panel data from Fixed Observation Point in rural China from 2009 to 2015 to estimate the impact of Internet access on dietary quality and food consumption of rural households and conducts a causal analysis.Regression models with time and household fixed effects allow robust estimation while reducing potential issues of unobserved heterogeneity.The estimates show that Internet access has significantly increased rural household dietary quality(measured by the Chinese Diet Balance Index).Further research finds that Internet access has increased the consumption of animal products,such as aquatic and dairy products.We also examine the underlying mechanisms.Internet access improves dietary quality and food consumption mainly through increasing household income and food expenditure.These results encourage the promotion of Internet access as a valuable tool for nutritional improvements,especially in rural areas. 展开更多
关键词 dietary quality fixed effect model Internet access rural china
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基于AHP和熵值法China Daily头版封面插画视觉感知评价研究
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作者 郭延龙 孙玉洁 《北京印刷学院学报》 2024年第1期53-60,共8页
为了探索报纸插图视觉中哪些因素对读者产生影响,提升阅读者的视觉感知水平,以China Daily头版封面插画为例,从内容层、形式、功能感知三个维度,建构出审美艺术性、创意趣味性、风格独特性、符号内涵性、标题内容区分度、色调内容协调... 为了探索报纸插图视觉中哪些因素对读者产生影响,提升阅读者的视觉感知水平,以China Daily头版封面插画为例,从内容层、形式、功能感知三个维度,建构出审美艺术性、创意趣味性、风格独特性、符号内涵性、标题内容区分度、色调内容协调度、色调舒适度、明度舒适度、纯度舒适度、图形大小舒适度、图形造型舒适度、构图留白舒适度等24个指标。结合问卷调查,利用层次分析法和熵值法进行统计分析。研究得出:读者对于China Daily封面插画的感知评价由高到低依次为形式层感知、功能层感知、内容层感知;构图留白舒适度、阅读动态性、叙事直观性等因素对读者视觉感知影响较大;从优化读者文化继承性、字体设计协调度、主题明确性等方面入手,有助于提升读者的视觉阅读体验。 展开更多
关键词 视觉感知 封面插画 china Daily 熵值法 层次分析法
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功能性产业政策能否促进企业生产率增长——基于《中国制造2025》的准自然实验
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作者 戴魁早 陈阿丽 杨新宇 《南开经济研究》 北大核心 2024年第2期43-63,共21页
本文在政府与市场关系分析框架下,理论分析制造强国战略这一功能性产业政策对企业全要素生产率的影响机制,并以《中国制造2025》为准自然实验,结合2010—2019年沪深A股上市公司数据,运用双重差分法对理论预期进行验证。研究发现,制造强... 本文在政府与市场关系分析框架下,理论分析制造强国战略这一功能性产业政策对企业全要素生产率的影响机制,并以《中国制造2025》为准自然实验,结合2010—2019年沪深A股上市公司数据,运用双重差分法对理论预期进行验证。研究发现,制造强国战略这一功能性产业政策显著地促进了制造业企业全要素生产率增长,这一结论在安慰剂检验、PSM-DID、工具变量法等一系列稳健性检验后仍然成立。制造强国战略的这种影响是通过协同创新、关键核心技术突破等技术创新机制,以及专业技术人才、经营管理人才等人才支撑机制实现的。政府治理效能提升显著增强了制造强国战略的实施效果,而且这种影响对于政府效率和营商环境排名前50的城市更显著。政府治理效能提升强化了制造强国战略的协同创新、关键核心技术突破、专业技术人才支撑和经营管理人才支撑等机制,但未明显改善创新溢出机制和技能人才支撑机制。此外,异质性分析表明,制造强国战略对试点地区、配套政策完善地区、融资约束程度较低、智能化水平较高、技术差距较大行业的企业生产率提升效果更为显著。本文的研究验证了制造强国战略在制造业生产率增长方面的重要作用,为功能性产业政策实施与制造业高质量发展提供了有益的参考依据。 展开更多
关键词 产业政策 中国制造2025 政府治理效能 高质量发展
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对外传播中的福州城市形象话语建构——以“十三五”期间China Daily报道为例
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作者 许洁 《武夷学院学报》 2024年第2期60-65,共6页
以“十三五”期间China Daily有关福州的报道为语料,以文化话语研究为理论框架,从话语主体、话语主题和话语形式三个方面探讨福州城市形象的话语建构。研究发现,总体上China Daily对外塑造了一个积极的福州城市形象,其中以文化形象最受... 以“十三五”期间China Daily有关福州的报道为语料,以文化话语研究为理论框架,从话语主体、话语主题和话语形式三个方面探讨福州城市形象的话语建构。研究发现,总体上China Daily对外塑造了一个积极的福州城市形象,其中以文化形象最受关注。此外,与以往同类研究相比,样本媒体进一步传递了普通民众的声音,更多使用人物通讯的报道形式,从而更有效地对外讲述了福州故事、中国故事。本研究对城市形象的话语建构与国际传播具有现实意义。 展开更多
关键词 福州 城市形象 对外传播 话语建构 文化话语研究 媒体话语 china Daily
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Differences in spring precipitation over southern China associated with multiyear La Ni?a events 被引量:1
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作者 Guangliang Li Licheng Feng +3 位作者 Wei Zhuang Fei Liu Ronghua Zhang Cuijuan Sui 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第2期1-10,共10页
Composite analyses were performed in this study to reveal the difference in spring precipitation over southern China during multiyear La Ni?a events during 1901 to 2015. It was found that there is significantly below-... Composite analyses were performed in this study to reveal the difference in spring precipitation over southern China during multiyear La Ni?a events during 1901 to 2015. It was found that there is significantly below-normal precipitation during the first boreal spring, but above-normal precipitation during the second year. The difference in spring precipitation over southern China is correlative to the variation in western North Pacific anomalous cyclone(WNPC), which can in turn be attributed to the different sea surface temperature anomaly(SSTA) over the Tropical Pacific. The remote forcing of negative SSTA in the equatorial central and eastern Pacific and the local air-sea interaction in the western North Pacific are the usual causes of WNPC formation and maintenance.SSTA in the first spring is stronger than those in the second spring. As a result, the intensity of WNPC in the first year is stronger, which is more likely to reduce the moisture in southern China by changing the moisture transport, leading to prolonged precipitation deficits over southern China. However, the tropical SSTA signals in the second year are too weak to induce the formation and maintenance of WNPC and the below-normal precipitation over southern China. Thus, the variation in tropical SSTA signals between two consecutive springs during multiyear La Ni?a events leads to obvious differences in the spatial pattern of precipitation anomaly in southern China by causing the different WNPC response. 展开更多
关键词 multiyear La Nina precipitation anomaly anomalous western North Pacific cyclone southern china
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CHINA PRINT 2025精彩亮相东南亚
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《智能印刷》 2023年第5期11-12,共2页
第十一届北京国际印刷技术展览会(CHINAPRINT2025)将于2025年5月15—19日在北京中国国际展览中心(顺义馆)隆重举办。自今年4月举办的第五届中国(广东)国际印刷技术展览会(PRINT CHINA 2023)启动以来,展会各项筹备工作正在稳步有序地进... 第十一届北京国际印刷技术展览会(CHINAPRINT2025)将于2025年5月15—19日在北京中国国际展览中心(顺义馆)隆重举办。自今年4月举办的第五届中国(广东)国际印刷技术展览会(PRINT CHINA 2023)启动以来,展会各项筹备工作正在稳步有序地进行中。 展开更多
关键词 PRINT T202 china
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The Origin of Mesozoic A-type Granitoids,Fujian Province,Southeast China:Insights from Geochronology,Mineralogy and Geochemistry
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作者 XIE Qifeng DONG Yunpeng +3 位作者 CAI Yuanfeng ZHAI Mingguo XIAO Aifang ZHANG Hong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第3期630-640,共11页
The magma sources,origins and precise forming ages of the miarolite from Qishan and Kuiqi intrusions are still uncertain.New results reveal that,miarolites from the Qishan and Kuiqi intrusions yield crystallization ag... The magma sources,origins and precise forming ages of the miarolite from Qishan and Kuiqi intrusions are still uncertain.New results reveal that,miarolites from the Qishan and Kuiqi intrusions yield crystallization ages of~101 and~98 Ma,and they have a high formation temperature(~910℃)and low oxygen fugacity value,indicating crystallization condition at low pressure in the upper crust with temperature of 678℃.The Qishan and Kuiqi miarolites are characterized by enrichment in SiO_(2) and high-K alkali,depletion in Ca and Mg,and belong to the high-K weak peraluminous rock series.The samples are enriched in HFSEs(i.e.,Ta,Zr and Hf)and LILEs(i.e.,Ba,P and Sr),depleted in Ba and Sr with the negative anomaly of Eu.In the primitive mantle normalized trace element spider diagram,the samples show a right-inclined‘seagull-type’pattern,combined the ratios of(La/Yb)_N,10000×Al/Ga,Rb/Nb and Nb/Ta etc.,they were proved to be alkaline A-type granite.Combined the characterize of the trace elements,they were derived from clay-rich source accompanied pelite melting,and subjected to K-feldspar crystallization fractional.The values of ε_(Hf)(t)and tDM2 are distributed in the range of-2.8 to 3.3 with~1.2 Ga,and-6.0 to 4.0 with~1.2 Ga,revealing that they were generated from the Mesoproterozoic Cathaysia basement rocks.The comprehensive research reveals the Kuiqi and Qishan intrusions derived from crust-mantle mixing and partial melting of the crust,respectively,resulting from lithospheric extension generated by the Paleo-Pacific Plate subducted into the European-Asian Plate. 展开更多
关键词 A-type granitoid GEOCHRONOLOGY extension SUBDUCTION MESOZOIC Southeast china
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Trace elements in magmatic and hydrothermal quartz:Implications on the genesis of the Xingluokeng Tungsten Deposit,South China
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作者 Qing-Qing Zhang You-Wei Chen Jian-Feng Gao 《Acta Geochimica》 EI CAS CSCD 2024年第3期441-458,共18页
The Xingluokeng deposit is the largest gran-ite-related tungsten deposit within the Wuyi metallogenic belt in South China.The Xingluokeng intrusion primarily consists of porphyritic biotite granite,biotite granite,and... The Xingluokeng deposit is the largest gran-ite-related tungsten deposit within the Wuyi metallogenic belt in South China.The Xingluokeng intrusion primarily consists of porphyritic biotite granite,biotite granite,andfine-grained granite.The deposit is represented by veinlet-disseminated mineralization with K-feldspathization and biotitization,alongside quartz-vein mineralization with gre-isenization and sericitization.This study investigates in-situ analyses of quartz compositions from both the intrusion and hydrothermal veinlets and veins.Trace element correlations indicate that trivalent Al^(3+)and Fe^(3+)replace Si^(4+)within the quartz lattice,with monovalent cations(such as Li^(+),Na^(+),and K^(+))primarily serving as charge compensators.Low Ge/Al ratios(<0.013)of quartz from granites suggest a mag-matic origin.The low Al/Ti and Ge/Ti ratios,accompanied by high Ti contents in quartz,suggest that the porphyritic biotite granite and biotite granite are characterized by rela-tively low levels of differentiation and high crystallization temperatures.In contrast,thefine-grained granite exhibits a higher degree of fractionation,lower crystallization tem-peratures,and a closer association with tungsten miner-alization.Ti contents in quartz from quartz veins indicate Qz-Ⅰformed at temperatures above 400°C,while Qz-Ⅱto Qz-Ⅴformed at temperatures below 350°C.Variations in different generations of quartz,as indicated by Al content and(Al+Fe)/(Li+Na+K)ratio,suggest that Qz-Ⅰprecipi-tated from a less acidicfluid with a stable pH,whereas Qz-Ⅱto Qz-Ⅴoriginated from a more acidicfluid with notable pH variations.Consequently,alkaline alteration and acidic alteration supplied the essential Ca and Fe for the precipita-tion of scheelite and wolframite,respectively,highlighting a critical mechanism in tungsten mineralization at the Xin-gluokeng deposit. 展开更多
关键词 QUARTZ Xingluokeng Tungsten deposit Trace elements South china
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CHINA PRINT 2025新闻发布会隆重召开
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《印刷工业》 2023年第6期22-23,共2页
2023年11月2日,第十一届北京国际印刷技术展览会(CHINA PRINT 2025)新闻发布会在上海浦东嘉里大酒店隆重举办。CHINA PRINT由中国印刷及设备器材工业协会(简称“中国印工协”)和中国国际展览中心集团有限公司(简称“中展集团”)共同主办... 2023年11月2日,第十一届北京国际印刷技术展览会(CHINA PRINT 2025)新闻发布会在上海浦东嘉里大酒店隆重举办。CHINA PRINT由中国印刷及设备器材工业协会(简称“中国印工协”)和中国国际展览中心集团有限公司(简称“中展集团”)共同主办,北京中印协华港国际展览有限公司承办,至今已成功举办了10届。近40年的发展历程,CHINA PRINT2025将于2025年5月15—19日在北京中国国际展览中心(顺义馆)隆重举行。 展开更多
关键词 PRINT 新闻发布会 china
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Synergistic Interdecadal Evolution of Precipitation over Eastern China and the Pacific Decadal Oscillation during 1951-2015
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作者 Minmin WU Rong-Hua ZHANG +1 位作者 Junya HU Hai ZHI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第1期53-72,共20页
By using the multi-taper method(MTM)of singular value decomposition(SVD),this study investigates the interdecadal evolution(10-to 30-year cycle)of precipitation over eastern China from 1951 to 2015 and its relationshi... By using the multi-taper method(MTM)of singular value decomposition(SVD),this study investigates the interdecadal evolution(10-to 30-year cycle)of precipitation over eastern China from 1951 to 2015 and its relationship with the North Pacific sea surface temperature(SST).Two significant interdecadal signals,one with an 11-year cycle and the other with a 23-year cycle,are identified in both the precipitation and SST fields.Results show that the North Pacific SST forcing modulates the precipitation distribution over China through the effects of the Pacific Decadal Oscillation(PDO)-related anomalous Aleutian low on the western Pacific subtropical high(WPSH)and Mongolia high(MH).During the development stage of the PDO cold phase associated with the 11-year cycle,a weakened WPSH and MH increased the precipitation over the Yangtze River Basin,whereas an intensified WPSH and MH caused the enhanced rain band to move northward to North China during the decay stage.During the development stage of the PDO cold phase associated with the 23-year cycle,a weakened WPSH and MH increased the precipitation over North China,whereas an intensified WPSH and the weakened MH increased the precipitation over South China during the decay stage.The 11-year and 23-year variabilities contribute differently to the precipitation variations in the different regions of China,as seen in the 1998flooding case.The 11-year cycle mainly accounts for precipitation increases over the Yangtze River Basin,while the 23-year cycle is responsible for the precipitation increase over Northeast China.These results have important implications for understanding how the PDO modulates the precipitation distribution over China,helping to improve interdecadal climate prediction. 展开更多
关键词 MTM-SVD PDO SST anomalies interdecadal variability precipitation over china
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How do the landslide and non-landslide sampling strategies impact landslide susceptibility assessment? d A catchment-scale case study from China
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作者 Zizheng Guo Bixia Tian +2 位作者 Yuhang Zhu Jun He Taili Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期877-894,共18页
The aim of this study is to investigate the impacts of the sampling strategy of landslide and non-landslide on the performance of landslide susceptibility assessment(LSA).The study area is the Feiyun catchment in Wenz... The aim of this study is to investigate the impacts of the sampling strategy of landslide and non-landslide on the performance of landslide susceptibility assessment(LSA).The study area is the Feiyun catchment in Wenzhou City,Southeast China.Two types of landslides samples,combined with seven non-landslide sampling strategies,resulted in a total of 14 scenarios.The corresponding landslide susceptibility map(LSM)for each scenario was generated using the random forest model.The receiver operating characteristic(ROC)curve and statistical indicators were calculated and used to assess the impact of the dataset sampling strategy.The results showed that higher accuracies were achieved when using the landslide core as positive samples,combined with non-landslide sampling from the very low zone or buffer zone.The results reveal the influence of landslide and non-landslide sampling strategies on the accuracy of LSA,which provides a reference for subsequent researchers aiming to obtain a more reasonable LSM. 展开更多
关键词 Landslide susceptibility Sampling strategy Machine learning Random forest china
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Spatial patterns of zooplankton abundance,biovolume,and size structure in response to environmental variables:a case study in the Yellow Sea and East China Sea
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作者 Song SUN Haochen XIAN +2 位作者 Xiaoxia SUN Mingliang ZHU Mengtan LIU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期113-127,共15页
The Yellow Sea(YS)and East China Sea(ECS)are highly dynamic marginal seas of the northwestern Pacific Ocean.To gain an in-depth understanding of zooplankton community structure,zooplankton abundance,biovolume,and size... The Yellow Sea(YS)and East China Sea(ECS)are highly dynamic marginal seas of the northwestern Pacific Ocean.To gain an in-depth understanding of zooplankton community structure,zooplankton abundance,biovolume,and size structure in summer 2017 in the YS and ECS were assessed using ZooScan imaging analysis.Zooplankton abundance and biovolume ranged 2.94–1187.14 inds./m^(3)and 3.13–3438.51 mm^(3)/m^(3),respectively.Based on the biovolume data of the categorized size classes of 26 identified taxonomic groups,the zooplankton community was classified into five groups,and each group was coupled with distinctive oceanographic features.Under the influence of the Yellow Sea Cold Water Mass,the Yellow Sea offshore group featured the lowest bottom temperature(10.84±3.42℃)and the most abundant Calanoids(mainly in the 2–3 mm size class).In the Yellow Sea inshore group,Hydrozoans showed the largest biovolume and dominated in the 3–4-mm and>5-mm size classes.The East China Sea offshore group,which was affected by the Kuroshio Branch Current,featured high temperature and salinity,and the lowest bottom dissolved oxygen(2.58±0.5 mg/L).The lowest values of zooplankton abundance and biovolume in the East China Sea offshore group might be attributed to the bottom dissolved oxygen contents.The East China Sea inshore group,which was mainly influenced by the Zhejiang-Fujian Coastal Current and Changjiang Diluted Water,was characterized by high chlorophyll a and the largest biovolume of carnivorous Siphonophores(280.82±303.37 mm^(3)/m^(3)).The Changjiang River estuary offshore group showed the most abundant Cyclopoids,which might be associated with the less turbid water mass in this region.Seawater temperature was considered the most important factor in shaping the size compositions of Calanoids in different groups. 展开更多
关键词 ZOOPLANKTON size structure ZooScan Yellow Sea East china Sea
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Examining the Spatiotemporal Dynamics and Determinants of Land Urbanization in Prefecture-level Cities,China
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作者 YANG Zhen ZHU Huxiao +1 位作者 ZHANG Xinlin OU Xiangjun 《Chinese Geographical Science》 SCIE CSCD 2024年第1期19-33,共15页
Examining the spatiotemporal dynamics and determinants of land urbanization is critical for promoting healthy urban development and the rational use of land resources.Based on the dataset consisting of land use change... Examining the spatiotemporal dynamics and determinants of land urbanization is critical for promoting healthy urban development and the rational use of land resources.Based on the dataset consisting of land use change data and selected factors in 2010 and2020,this study used visual analysis to reveal the spatiotemporal dynamics of land urbanization across prefecture-level cities in China.Meanwhile,the driving forces underlying land urbanization were examined by using geographical detector technique.Following are the findings:1)we find that there exist notable spatial variances in land urbanization across prefecture-level cities.Currently,the differentiation in land urbanization between the northern and southern cities is more pronounced than that between the coastal and inland cities,or between the eastern and western cities.Prefecture-level cities located in central and western China have experienced the most rapid growth in land urbanization.Conversely,the growth rate in northeastern China is the lowest,while the velocity in eastern China remains relatively stable.By using spatial autocorrelation analysis,this study reveals that the land urbanization level in prefecture-level cities has significant spatial agglomeration.2)We further find that land urbanization in China is influenced by factors related to urban land supply and demand,and urban population growth,economic growth,land financial and political incentive have greater impact on land urbanization than other factors.3)We also find that the impacts of determinants on China’s land urbanization vary over time,the explanatory power of economic development increased,while the explanatory power of state forces declined.We argue that integrating the supply and demand factors of land urbanization can provide a more comprehensive understanding of the driving mechanisms underlying land urbanization in China and other transitional countries,and help decision-makers in these countries formulate more detailed and specific land urbanization policies. 展开更多
关键词 land urbanization spatial pattern influencing factor geographical detector china
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Characteristics of the HIV/AIDS Epidemic among People Aged≥50 Years in China during 2018–2021
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作者 HOU Yu Shan JIN Yi Chen +3 位作者 CAI Chang TANG Hou Lin QIN Qian Qian LYU Fan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第4期399-405,共7页
Objective This study aimed to determine the current epidemiological status of PLWHA aged≥50 years in China from 2018 to 2021.It also aimed to recommend targeted interventions for the prevention and treatment of HIV/A... Objective This study aimed to determine the current epidemiological status of PLWHA aged≥50 years in China from 2018 to 2021.It also aimed to recommend targeted interventions for the prevention and treatment of HIV/AIDS in elderly patients.Methods Data on newly reported cases of PLWHA,aged≥50 years in China from 2018 to 2021,were collected using the CRIMS.Trend tests and spatial analyses were also conducted.Results Between 2018 and 2021,237,724 HIV/AIDS cases were reported among patients aged≥50 years in China.The main transmission route was heterosexual transmission(91.24%).Commercial heterosexual transmission(CHC)was the primary mode of transmission among males,while non-marital non-CHC([NMNCHC];60.59%)was the prevalent route in women.The proportion of patients with CHC decreased over time(Z=67.716,P<0.01),while that of patients with NMNCHC increased(Z=153.05,P<0.01).The sex ratio varied among the different modes of infection,and it peaked at 17.65 for CHC.The spatial analysis indicated spatial clustering,and the high-high clustering areas were mainly distributed in the southwestern and central-southern provinces.Conclusion In China,PLWHA,aged≥50 years,were predominantly infected through heterosexual transmission.The primary modes of infection were CHC and NMNCHC.There were variations in the sex ratio among different age groups,infected through various sexual behaviors.HIV/AIDS cases exhibited spatial clustering.Based on these results,the expansion of HIV testing,treatment,and integrated behavioral interventions in high-risk populations is recommended to enhance disease detection in key regions. 展开更多
关键词 HIV/AIDS Aged≥50 years china
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Assessment of International GNSS Service Global Ionosphere Map products over China region based on measurements from the Crustal Movement Observation Network of China 被引量:1
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作者 Jin Hu HaiBing Ruan +2 位作者 FuQing Huang ShengYang Gu XianKang Dou 《Earth and Planetary Physics》 EI CAS CSCD 2024年第2期400-407,共8页
The global ionosphere maps(GIM)provided by the International GNSS Service(IGS)are extensively utilized for ionospheric morphology monitoring,scientific research,and practical application.Assessing the credibility of G... The global ionosphere maps(GIM)provided by the International GNSS Service(IGS)are extensively utilized for ionospheric morphology monitoring,scientific research,and practical application.Assessing the credibility of GIM products in data-sparse regions is of paramount importance.In this study,measurements from the Crustal Movement Observation Network of China(CMONOC)are leveraged to evaluate the suitability of IGS-GIM products over China region in 2013-2014.The indices of mean error(ME),root mean square error(RMSE),and normalized RMSE(NRMSE)are then utilized to quantify the accuracy of IGS-GIM products.Results revealed distinct local time and latitudinal dependencies in IGS-GIM errors,with substantially high errors at nighttime(NRMSE:39%)and above 40°latitude(NRMSE:49%).Seasonal differences also emerged,with larger equinoctial deviations(NRMSE:33.5%)compared with summer(20%).A preliminary analysis implied that the irregular assimilation of sparse IGS observations,compounded by China’s distinct geomagnetic topology,may manifest as error variations.These results suggest that modeling based solely on IGS-GIM observations engenders inadequate representations across China and that a thorough examination would proffer the necessary foundation for advancing regional total electron content(TEC)constructions. 展开更多
关键词 International GNSS Service(IGS)Global Ionosphere Maps(GIM) Crustal Movement Observation Network of china(CMONOC) total electron content(TEC) data assessment
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Spatio-Temporal Characteristics of Heavy Precipitation Forecasts from ECMWF in Eastern China
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作者 徐同 谭燕 顾问 《Journal of Tropical Meteorology》 SCIE 2024年第1期29-41,共13页
This study examines the spatio-temporal characteristics of heavy precipitation forecasts in eastern China from the European Centre for Medium-Range Weather Forecasts(ECMWF) using the time-domain version of the Method ... This study examines the spatio-temporal characteristics of heavy precipitation forecasts in eastern China from the European Centre for Medium-Range Weather Forecasts(ECMWF) using the time-domain version of the Method for Object-based Diagnostic Evaluation(MODE-TD). A total of 23 heavy rainfall cases occurring between 2018 and 2021 are selected for analysis. Using Typhoon “Rumbia” as a case study, the paper illustrates how the MODE-TD method assesses the overall simulation capability of models for the life history of precipitation systems. The results of multiple tests with different parameter configurations reveal that the model underestimates the number of objects’ forecasted precipitation tracks, particularly at smaller radii. Additionally, the analysis based on centroid offset and area ratio tests for different classified precipitation objects indicates that the model performs better in predicting large-area, fast-moving, and longlifespan precipitation objects. Conversely, it tends to have less accurate predictions for small-area, slow-moving, and shortlifespan precipitation objects. In terms of temporal characteristics, the model overestimates the forecasted movement speed for precipitation objects with small-area, slow movement, or both long and short lifespans while underestimating it for precipitation with fast movement. In terms of temporal characteristics, the model tends to overestimate the forecasted movement speed for precipitation objects with small-area, slow movement, or both long and short lifespans while underestimating it for precipitation with fast movement. Overall, the model provides more accurate predictions for the duration and dissipation of precipitation objects with large-area or long-lifespan(such as typhoon precipitation) while having large prediction errors for precipitation objects with small-area or short-lifespan. Furthermore, the model’s simulation results regarding the generation of precipitation objects show that it performs relatively well in simulating the generation of large-area and fast-moving precipitation objects. However, there are significant differences in the forecasted generation of small-area and slow-moving precipitation objects after 9 hours. 展开更多
关键词 MODE-TD ECMWF heavy precipitation Eastern china
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