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FOUNDATION AND APPLICATION OF BACKGROUND TREND LINE OF CHINA'S INBOUND TOURISM
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《Chinese Geographical Science》 SCIE CSCD 2000年第3期40-46,共2页
SUN Gen nian (Shaanxi Normal University, Xi’an 710062,P.R.China) ABSTRACE:Modern inbound tourism in China has been developing for 20 years, a trend line of inbound tourists in statistical data began to show. This pap... SUN Gen nian (Shaanxi Normal University, Xi’an 710062,P.R.China) ABSTRACE:Modern inbound tourism in China has been developing for 20 years, a trend line of inbound tourists in statistical data began to show. This paper introduces the concept of tourism background trend line, and explores its two functions as a barometer in demonstrating fluctuation in the tourism economy and as a forecaster in forecasting tourism development. The tourism background trend line is a new concept, the word "background" derived from environment science, refers to the  trend line" which reflects the dynamic curve or dynamic equation of tourism development without considering the impact of unexpected incidents. The introduction of this concept was inspired by Karl Marx’s comments on the relation between value and price. Tourism background trend line reflects the summary of multiple factors involving tourism resources, tourism demand, population growth, the scale and speed of economic development, and the spatial interaction between tourism origins and destimations. It demonstrates the natural and stable trend and the temporal law of tourism development in a country or region. The tourism statistical curve is at random, susceptible to disruptions and disturbances from serious political, economic and environmental happenings, but it always fluctuates around the background line. Tourism background line can reveal the potential of a country’s tourism development. Compared with the statistical line, it can be used as a  barometer" indicating ups and downs of tourism industry in the past. When naturally extended, the background trend line also can be used for forecasting the trend of tourism development in future. In this paper, 4 tourism background trend lines of China’s inbound tourists, i.e. foreign tourists, Hong Kong/Macao/Taiwan tourists, overseas Chinese tourists and total tourists from abroad, were established with statistical data from 1978 to 1996. And the impacts of the Political Event in 1989(or Tiananmen Square Incident) on China’s inbound tourism were evaluated. The result shows that the impact of the Event was not limited within one year, but it stretched over 3 years. The total loss was 20 million in tourist arrivals and $ 1620 million in foreign currency income. The paper also studied the trend of China’s inbound tourism in the next 4 years. 展开更多
关键词 inbound TOURISM background trend line BAROMETER FUNCTION predictive FUNCTION application
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Research on the Development Direction and Trend of Interior Design Education under the Green Building Background
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作者 Jianwei Ban 《International Journal of Technology Management》 2016年第2期91-93,共3页
In this paper, we conduct research on the development direction and trend of interior design education under the green building background. Due to the development of the social economy and people living standard rise,... In this paper, we conduct research on the development direction and trend of interior design education under the green building background. Due to the development of the social economy and people living standard rise, the public has produced great changes to the requirement of the interior design, for interior designers professional ability is also put forward higher requirements. As the main position of interior design talent cultivation, universities of professional interior design must be according to these changes, corresponding education reform. Reform must be from the construction of curriculum system, teaching content and teaching method and so on as all aspects of interior design education to promote at the same time, in order to achieve their purpose. Our research proposes the novel paradigm for the interior design education which will enhance the current teaching mode. 展开更多
关键词 Green Building Interior Design Direction and trend background Education.
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Research on the Developmental Trend of Computer Music Technology under the Background of Multi-channel Stereo Recording
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作者 Mou Xin 《International Journal of Technology Management》 2016年第8期36-38,共3页
In this paper, we conduct research on the developmental trend of the computer music technology under the background of multichannelstereo recording. Surround sound is not only used in the fi lm, home theater, also pen... In this paper, we conduct research on the developmental trend of the computer music technology under the background of multichannelstereo recording. Surround sound is not only used in the fi lm, home theater, also penetrated the digital TV and digital broadcasting.But because of the limitation of storage media capacity and transmission bandwidth must use all kinds of that audio compression technologyto transmit audio data. As a more general and more practical signifi cance, as masking and by masking sound are not limited to their respectiveresend by a single speaker, but in different proportion to their respective ‘channel sound level is poor. To deal with this issue, this paperintegrates the signal denoising method as the optimization and achieves better performance. 展开更多
关键词 Computer Music Multi-channel Stereo Recording background Developmental trend.
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Research on the Traditional Chinese Painting under the New Media Era Background
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作者 Meng Wang Zuobin Li 《International Journal of Technology Management》 2016年第3期40-42,共3页
In this paper, we conduct theoretical research on the traditional Chinese painting under the new media era background. Each kind of art has its own language, has its performance tell their own special form of expressi... In this paper, we conduct theoretical research on the traditional Chinese painting under the new media era background. Each kind of art has its own language, has its performance tell their own special form of expression, if the dance art is by dancers from its own unique aesthetic consciousness and aesthetic ideal, by means of the human body, in the process of regular exercise to create a dynamic artistic beauty. That painting is the painter with his own eyes see the world, feel the beauty after understanding of beauty themselves by their own hands drawing on paper, as use this form to us leave world presents to the world. In the development of Chinese painting, pen and ink are inseparable, dependent, both in line shape, with luck, melts the things rather than the external object revealed the existence of ontology and ink lines, this is the spirit of Chinese painting. To enhance the development of the Chinese painting, we integrate the new media for innovative optimization. 展开更多
关键词 Chinese Painting New Media Era background TRADITIONAL Development trend.
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Research on Development Outline of Contemporary Art of Chinese Sports under the Background of Differences between Chinese and Western Culture
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作者 Yingdong Song 《International Journal of Technology Management》 2016年第4期4-6,共3页
In this paper, we conduct research on development outline of contemporary art of Chinese sports under the background of differences between Chinese and western culture. The development of any industry must experience ... In this paper, we conduct research on development outline of contemporary art of Chinese sports under the background of differences between Chinese and western culture. The development of any industry must experience the formation, growth, maturity and decline of the industry life cycle. Its period in the entire industry by the proportion of growth, the sports industry is no exception. But due to the particularity of the Chinese system, China’s sports industry life cycle has its particularity. Technology, is the carrier of knowledge talent, technology, knowledge of competition, is essentially talent competition while the country is increasing investment in sports industry, scientifi c research, education, strengthen the training of management personnel, to improve the quality of sports market management. Therefore, we propose the novel idea on the issues that is meaningful. 展开更多
关键词 DEVELOPMENT OUTLINE Chinese SPORTS CULTURE background basic DIFFERENCES
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Significant downward trend of SO_2 observed from 2005 to 2010 at a background station in the Yangtze Delta region,China 被引量:7
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作者 QI HuangXiong LIN WeiLi +2 位作者 XU XiaoBin YU XiangMing MA QianLi 《Science China Chemistry》 SCIE EI CAS 2012年第7期1451-1458,共8页
SO2 is an important gas in atmosphere with great environmental and climate implications.SO2 emission in China has been receiving great attention as the economy grows and the amount of coal consumption has increased in... SO2 is an important gas in atmosphere with great environmental and climate implications.SO2 emission in China has been receiving great attention as the economy grows and the amount of coal consumption has increased in the past few decades.SO2 has been observed from July 2005 to June 2010 at Linan WMO GAW regional station(30.3 °N,119.73 °E,138 m a.s.l.) located in the Yangtze Delta region in eastern China.These observation data are analyzed to understand the trend of regional SO2 background concentration.Strict quality controls are conducted to ensure the temporal comparability of the data.Significant downward trend with ?2.4 ppb/yr(P < 0.0001) of surface SO2 is observed from 2005 to 2010,especially after 2008.The average concentration of SO2 from July 2005 to June 2008 is 14.2±3.1 ppb,which is slightly higher than the mean values of 13.5±5.1 ppb during 1999?2000 and is two folds of the average value(7.1±3.1 ppb) from July 2008 to June 2010.More than 50% of the SO2 has been cut down after 2008 in the Yangtze Delta region due to the implementation of stricter emission control measures.The peak SO2 concentration appears around 10 o'clock in the morning after 2009 while appears at night before 2009.These diurnal variations of SO2 might indicate that after 2009,more SO2 is from the vertical exchange process than from the local accumulation. 展开更多
关键词 SO2 background level trend Yangtz Delta Region
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BACKGROUND VALUES AND TREND DISTRIBUTION OF Cu, Zn AND Ni IN SOILS IN CHINA
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作者 王景华 《Chinese Geographical Science》 SCIE CSCD 1992年第4期67-76,共10页
The background values of Cu, Zn and Ni are discussed based on the analytical data of 21 main soil types collected from various regions in China. According to statistics of many samples, the background value of Cu is 2... The background values of Cu, Zn and Ni are discussed based on the analytical data of 21 main soil types collected from various regions in China. According to statistics of many samples, the background value of Cu is 23.4±10.2 mg/ kg (482 samples), Zn 77.9±2.39 mg/ kg (474 samples), Ni 30.0±12.8 mg/kg (482 samples). 展开更多
关键词 Soil background VALUES of CU ZN and NI trend DISTRIBUTION
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新世纪以来我国铀矿地质科技创新重要进展及展望 被引量:4
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作者 秦明宽 李子颖 +11 位作者 刘章月 黄少华 蔡煜琦 刘祜 叶发旺 李怀渊 葛祥坤 张杰林 程纪星 郭冬发 李博 朱鹏飞 《铀矿地质》 CAS CSCD 2024年第2期189-203,共15页
新世纪以来,我国铀矿地质勘查领域重大理论和技术创新成果,极大地改变了我国砂岩型、热液型铀矿的找矿思路、找矿方向,引领、支撑了系列找矿重大突破,重塑了铀矿勘查新格局。文章首先分析了我国20余年来铀矿地质科研布局的总体思路与演... 新世纪以来,我国铀矿地质勘查领域重大理论和技术创新成果,极大地改变了我国砂岩型、热液型铀矿的找矿思路、找矿方向,引领、支撑了系列找矿重大突破,重塑了铀矿勘查新格局。文章首先分析了我国20余年来铀矿地质科研布局的总体思路与演进方向;然后总结了铀矿重大基础地质与成矿理论研究进展,系统凝练了地质、物化探、遥感、钻探工艺、分析测试等领域的技术创新及核心勘查装备研制成果,梳理了铀资源预测评价技术研究进展及应用成效;最后,在重大基础前沿和成矿理论、先进铀矿勘查技术研发、非常规核能裂变资源勘查技术研究、数字铀矿勘查技术开发等方面提出了未来10~15年主要发展趋势和方向,指出在“双碳”目标和核能大发展对铀资源保障需求背景下,必须继续坚持并加强铀矿地质科技创新,高质量引领和推动“新区、新层位、新类型、新深度”找矿突破。 展开更多
关键词 科技创新 铀矿基础地质与成矿理论 勘查技术及装备 预测评价技术 发展趋势和方向
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国际基础教育质量监测的数字化转型:实践路径、支持保障与经验借鉴
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作者 王正青 杜丽玮 《中国考试》 CSSCI 北大核心 2024年第8期89-98,共10页
当前世界各国基础教育质量监测主动适应数字发展潮流,纷纷走上数字化转型之路。部分发达国家以数字化测试为手段创新监测形式,以数字素养为对象拓宽监测内容,以数字化诊断为载体建立早期预警系统,并以数字化系统为工具进行常态化监测,... 当前世界各国基础教育质量监测主动适应数字发展潮流,纷纷走上数字化转型之路。部分发达国家以数字化测试为手段创新监测形式,以数字素养为对象拓宽监测内容,以数字化诊断为载体建立早期预警系统,并以数字化系统为工具进行常态化监测,全链条推进数字化转型。在推进转型的过程中,各国从战略规划、教师数字素养、技术支持、组织建设等多方面建立起支撑保障体系。立足我国基础教育质量监测实际,在推进数字化转型过程中应健全多元监测主体,优化监测流程,开发与利用新型数字监测工具,并有效规避智能技术潜在风险。 展开更多
关键词 基础教育 质量监测 数字化转型 智能化监测 国际趋势
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量子信息领域的国家战略布局与研发态势分析 被引量:6
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作者 宋姗姗 钟永恒 +1 位作者 刘佳 刘盼盼 《世界科技研究与发展》 CSCD 2024年第1期21-35,共15页
近年来,以量子计算、量子通信和量子测量为代表的量子信息领域持续活跃,已经成为基础研究探索、颠覆性技术创新以及未来产业变革的重要发展方向,因此明晰量子信息领域的发展态势,对于我国建设世界科技强国具有重要价值。本文首先介绍了... 近年来,以量子计算、量子通信和量子测量为代表的量子信息领域持续活跃,已经成为基础研究探索、颠覆性技术创新以及未来产业变革的重要发展方向,因此明晰量子信息领域的发展态势,对于我国建设世界科技强国具有重要价值。本文首先介绍了量子信息领域的相关概念与研究现状,其次分析了美国、欧盟、英国、日本、中国的量子战略布局,最后结合论文与专利的多维度计量分析,展示了量子信息领域的研发态势。研究发现:当前量子信息领域正处于迅猛发展阶段,国际科技强国都高度重视在该领域的政策布局、资金投入、人才引育和国际合作等,其中美国最具优势;中国在量子通信及量子计算领域基本跻身核心位置,未来还需要加速实施量子信息领域战略部署、积极引聚育留量子信息科技人才、深度推进量子领域产学研协同创新等。 展开更多
关键词 量子信息 国家战略 研发态势 基础研究 产学研合作
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突出电路分析基础课程军事特色的教学探索
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作者 彭赛阳 高敬祥 +1 位作者 崔晶晶 朱迎新 《空天预警研究学报》 CSCD 2024年第3期231-234,共4页
针对军校专业背景的电路分析基础课程存在知识层面过于基础、含“军”量不高、军事特色不够突出的问题,分析了该课程教学建设现状;指出了军事特色方面教学内容、课程建设以及教员军事素养方面的不足;围绕课程建设中教学内容、课堂思政... 针对军校专业背景的电路分析基础课程存在知识层面过于基础、含“军”量不高、军事特色不够突出的问题,分析了该课程教学建设现状;指出了军事特色方面教学内容、课程建设以及教员军事素养方面的不足;围绕课程建设中教学内容、课堂思政、课程结构、教员军事素养四个方面如何改进加强课程军事特色提出了相应的对策措施.教学实践表明,这些措施对于激发学员学习兴趣、提升教学效果有一定作用. 展开更多
关键词 电路分析基础课程 专业背景课程 军事特色
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海洋地质专业背景浅析及其对职业教育地质类专业的启示
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作者 赵春晨 李捷斌 +4 位作者 王宁 杨谦 丁瑶 张祎薇 秦晓艳 《地下水》 2024年第5期185-188,共4页
地勘行业是我国的重要支撑行业。培养高素质的地质类职业技能型人才将为地勘行业的发展、城市建设的推动乃至国家资源安全的保障等提供重要支撑。另一方面作为21世纪备受重视的勘查领域专业,海洋地质在地球科学领域同样显现出了它特有... 地勘行业是我国的重要支撑行业。培养高素质的地质类职业技能型人才将为地勘行业的发展、城市建设的推动乃至国家资源安全的保障等提供重要支撑。另一方面作为21世纪备受重视的勘查领域专业,海洋地质在地球科学领域同样显现出了它特有的地位。二者虽然在教育教学方法上存在一定的差异,但其目标都是为地质领域培养素养全面型人才,进而推动地质领域的不断发展。海洋地质专业的强实践性、学科交叉性以及广阔覆盖性可为职业教育地质类专业人才培养提供新的教育理念和思路,从而提升职业教育地质类专业的就业竞争力,让学生在未来的就业过程中更具优势。基于此,本文从海洋地质专业的特点、海洋地质学的自身发展、海洋地质学及其专业的研究内容和地位出发,浅析各学科与海洋地质学科的交叉渗透、相互促进,全面展示海洋地质专业的特点和优势,最终进一步引申出对今后海洋地质学发展动向的思考及其对职业教育地质类专业的启示,以期为职业教育地质类专业的未来发展提供有力支撑。 展开更多
关键词 专业背景 学科交叉 发展动向 启示
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新型基础测绘技术的研究与应用
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作者 黄铭 覃现 +2 位作者 李奇 夏海波 赵薛强 《测绘通报》 CSCD 北大核心 2024年第S02期46-49,共4页
随着科技的不断进步,传统的基础测绘技术已经逐渐无法满足日益增长的需求,新型基础测绘技术的涌现成为解决这一问题的重要途径。本文列出了传统测绘技术存在的局限性和不足之处,着重介绍了新型基础测绘技术,包括全球定位系统(GPS)、卫... 随着科技的不断进步,传统的基础测绘技术已经逐渐无法满足日益增长的需求,新型基础测绘技术的涌现成为解决这一问题的重要途径。本文列出了传统测绘技术存在的局限性和不足之处,着重介绍了新型基础测绘技术,包括全球定位系统(GPS)、卫星遥感技术、无人机测绘等,探讨了这些新型技术在土地管理、城市规划、环境监测等方面的应用,并指出了其在提高测绘效率、精度和数据处理能力方面的优势,对未来新型基础测绘技术的发展趋势进行了展望,提出了进一步研究和应用的建议,以期为相关领域的研究和实践提供参考。 展开更多
关键词 新型基础测绘技术 地理信息 发展趋势 应用
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我国基础研究人才的学科分布与发展趋势研究
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作者 刘晔 柳学智 苗月霞 《中国人事科学》 2024年第5期31-39,共9页
基础研究人才是基础学科研究的主体,承担着更新科学知识与创新创造的重要使命。了解和评估基础研究人才的学科分布和发展趋势,是相关政策制定和理论研究的重要依据,对基础研究人才培养和全球重要人才中心建设具有重要意义。本文从科睿唯... 基础研究人才是基础学科研究的主体,承担着更新科学知识与创新创造的重要使命。了解和评估基础研究人才的学科分布和发展趋势,是相关政策制定和理论研究的重要依据,对基础研究人才培养和全球重要人才中心建设具有重要意义。本文从科睿唯安InCites数据库抽取文献数据,将被引次数累计百分比处于前10%的文献的作者界定为基础研究人才,以1‰、1%、10%为标线将其划分为A、B、C三个层次,对我国基础研究人才在各学科领域的分布情况与发展趋势进行了大数据分析,为了解我国基础研究人才总体及各层次的发展趋势提供多维度、多层面的分析方法和研究视角,为精准制定人才发展与支持政策提供实证参考。 展开更多
关键词 基础研究人才 文献计量分析 学科分布 发展趋势
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自升式钻井平台退出年限研究
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作者 刘备 刘振方 +2 位作者 王晶一 朱跃 李海鑫 《化工管理》 2024年第8期114-116,共3页
通过断点拟合方法构造了完整的自升式平台全生命周期成本基础曲线。将成本本底趋势线理论引入到钻井平台管理中,采用经济学成本理论建立了自升式平台退出年限理论模型,确定了自升式钻井平台的退出年限,对平台管理具有指导意义。
关键词 自升式钻井平台 退出年限 本底趋势线
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构建人类命运共同体的理论基础及实践路径
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作者 郭佳楠 赵姗 《无锡职业技术学院学报》 2024年第1期62-68,共7页
习近平总书记在二十大报告中多次提到了构建人类命运共同体。人类命运共同体理念的产生具有深厚的历史积淀和现实依据,旨在解决全球发展难题,为世界政治、安全、经济、文化、生态等方面的发展提供指引。从时代背景、理论基础和实践要求... 习近平总书记在二十大报告中多次提到了构建人类命运共同体。人类命运共同体理念的产生具有深厚的历史积淀和现实依据,旨在解决全球发展难题,为世界政治、安全、经济、文化、生态等方面的发展提供指引。从时代背景、理论基础和实践要求的角度分析构建人类命运共同体的深刻内涵,指出要在实践中积极谋求共识,坚持同舟共济的理念,尊重多元化差异,开展协商对话与交流,塑造权责共担的责任共同体,不断推动人类命运共同体的构建,为各国的交流合作搭建多种形式、多种层次的网络平台。 展开更多
关键词 党的二十大 人类命运共同体 时代背景 基本内涵 实践路径
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Global aridification in the second half of the 20th century and its relationship to large-scale climate background 被引量:18
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作者 MA ZhuGuo FU CongBin 《Science China Earth Sciences》 SCIE EI CAS 2007年第5期776-788,共13页
The variation in surface wetness index (SWI), which was derived from global gridded monthly precipi- tation and monthly mean surface air temperature datasets of Climatic Research Unit (CRU), from 1951― 2002 over glob... The variation in surface wetness index (SWI), which was derived from global gridded monthly precipi- tation and monthly mean surface air temperature datasets of Climatic Research Unit (CRU), from 1951― 2002 over global land was analyzed in this paper. The characteristics of the SWI variation in global continents, such as North America, South America, Eurasia, Africa, and Australia, were compared. In addition, the correlation between the SWI variation of each continent (or across the globe) and the large-scale background closely related to SST variations, which affects climate change, was analyzed. The results indicate that the SWI variation shows distinct regional characteristics in the second half of the 20th century under global warming. A drying trend in the last 52 years occurred in Africa, Eurasia, Australia and South America, most obviously in Africa and Eurasia. North America shows a wetting trend after 1976. A 30-year period of dry-wet oscillation is found in South America and Australia; the latest is in a drying period in two regions. The results also revealed that global warming has changed the dry-wet pattern of the global land. South America and Australia have a drying trend despite in- creases in precipitation. This indicates that increases in surface air temperature cannot be ignored in aridification studies. Global dry-wet variation is closely related to large-scale SST variations: the drying trend in Africa and Eurasia and the wetting trend in North America are correlated with Pacific Decadal Oscillation (PDO); the interdecadal oscillation of SWI in South America and Australia is consistent with the interdecadal variation in Southern Oscillation Index (SOI). 展开更多
关键词 GLOBAL dry-wet VARIATION drying trend LARGE-SCALE background INTERDECADAL VARIATION correlation
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CO_2 background concentration in the atmosphere over the Chinese mainland 被引量:9
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作者 WANG Gengchen, WEN Yupu, KONG Qinxin, REN Lixin & WANG MulinInstitute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China Academy of Meteorological Sciences, China Meteorological Administration, Beijing 100086, China 《Chinese Science Bulletin》 SCIE EI CAS 2002年第14期1217-1220,共4页
Based on the long-term monitoring data on CO2 concentration, variation trend and characteristics of CO2 background concentration in the atmosphere over the Chinese mainland are analyzed. Results show that the increasi... Based on the long-term monitoring data on CO2 concentration, variation trend and characteristics of CO2 background concentration in the atmosphere over the Chinese mainland are analyzed. Results show that the increasing trend of CO2 background concentration in the atmosphere over the Chinese mainland has appeared during the period of 1991-2000. The average annual CO2 growth increment is 1.59μL/L, and the average annual CO2 growth rate is 0.44%. Distinct seasonal variations of CO2 background concentration are observed, and the averaged amplitude of CO2 seasonal variations is 10.35μL/L. Regional variation characteristics of CO2 background concentration in the atmosphere and possible impact of human activities on these variations over the Chinese mainland are discussed as well. 展开更多
关键词 CO2 background concentration Chinese MAINLAND CO2 growth rate CO2 SEASONAL VARIATION CO2 regional VARIATION CO2 VARIATION trend.
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Long-term variations of major atmospheric compositions observed at the background stations in three key areas of China 被引量:8
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作者 ZHANG Yong JIN Jun-Li +10 位作者 YAN Peng TANG Jie FANG Shuang-Xi LIN Wei-Li LOU Meng-Yun LIANG Miao ZHOU Qing JING Jun-Shan LI Ya-Nan JIA Xiao-Fang LYU Shan-Shan 《Advances in Climate Change Research》 SCIE CSCD 2020年第4期370-380,共11页
Atmospheric compositions and acid rain are closely related to atmospheric environment,weather,and climate change.In this study,the concentration levels and long-term trends of CO_(2),CH_(4),O_(3),PM_(2.5),PM_(10),and ... Atmospheric compositions and acid rain are closely related to atmospheric environment,weather,and climate change.In this study,the concentration levels and long-term trends of CO_(2),CH_(4),O_(3),PM_(2.5),PM_(10),and acid rain were presented at the Mt.Waliguan global baseline station in Qinghai,Shangdianzi and Lin'an regional background stations in the North China Plain(NCP)and the Yangtze River Delta region(YRD)of China based on the data observed until 2018.Significant increasing trends of CO_(2) were found at all of these stations.At Mt.Waliguan,the concentration levels and growth rate were consistent with the average values in the Northern Hemisphere(NH)and those observed at the Mauna Loa station in Hawaii.The CH_(4) also showed a upward tendency similar to that observed in NH.Compared with the observations at Mt.Waliguan global baseline station,the CO_(2) and CH_(4) mole fractions were higher at Shangdianzi and Lin'an regional background stations,indicating the important contributions of anthropogenic activities to the regional background level of CO_(2) and CH_(4).The annual averaged surface ozone showed increasing trends at Mt.Waliguan and Shangdianzi stations,whereas no clear trend was found at Lin'an station.Similar variations in the patterns of aerosol concentrations at Shangdianzi and Lin'an were found according to the PM_(2.5) or PM_(10) observations.Overall,the aerosol concentrations at both stations shown declining trends since the observations.However,two periods of high particle concentrations occurred in 2006-2007 and 2013-2014.The annual mean aerosol concentrations have continuously decreased after 2013-2014,indicating the effectiveness of pollution control in the NCP and YRD,especially since the implementation of the‘Action Plan for Prevention and Control of Air Pollution’in September 2013.Comparative analysis of aerosol with acid rain showed that the period with high concentrations of aerosols in the early years was consistent with that of severe acid rain pollution,suggesting that both aerosol pollution and severe acid rain are closely related to coal combustion emissions in China.As a result of the control of coal combustion emissions for acid and SO_(2),NO_(x) emissions have contributed more substantially to aerosols due to the rapid growth of vehicle ownership.A comparison of the trends of aerosols with the maximum daily 8-h average of surface ozone(MDA8)at Shangdianzi and Lin'an stations revealed the complicated relationship between aerosol reduction and ozone production,i.e.,together with the continuous improvement of particulate pollution in the NCP and YRD,the MDA8 at both stations showed a decreasing trend at first but subsequently increased after 2014 with aerosols remaining reduced.Such different variation patterns of the MDA8 with PM_(2.5)(or PM_(10))indicated the high challenge of synergic control of aerosol and ozone pollution in China. 展开更多
关键词 Atmospheric compositions background observations Long-term variation trend Coordinated control of PM and ozone China
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国家水网基础认知与建构准则 被引量:7
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作者 赵勇 何凡 +3 位作者 何国华 王丽川 路培艺 王浩 《南水北调与水利科技(中英文)》 CAS CSCD 北大核心 2023年第6期1049-1054,1063,共7页
现阶段对国家水网的基础理论认知与系统性研究还较为薄弱,在很大程度上制约了国家水网的科学规划和建设。为此,从国家水网的基础认知入手,分析网、水网和国家水网的基本概念,从水网结构、承载物、演进规律、功能作用、类型划分等主要特... 现阶段对国家水网的基础理论认知与系统性研究还较为薄弱,在很大程度上制约了国家水网的科学规划和建设。为此,从国家水网的基础认知入手,分析网、水网和国家水网的基本概念,从水网结构、承载物、演进规律、功能作用、类型划分等主要特征初步探索水网的基础性问题;提出以实现健康水循环为核心目标,以促进六大均衡为基本准则和“确有需要、生态安全、可以持续”为重大工程论证原则的水网建设目标准则;展望未来水网发展“六化”新趋势,以期在理论层面为科学构建国家水网提供支撑。 展开更多
关键词 国家水网 基础认知 准则 趋势
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