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基于改进IDI指标体系的G20成员国信息通信技术发展水平研究
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作者 刘亚丽 唐宏博 +2 位作者 林茜妍 梁正 赵新力 《全球科技经济瞭望》 2023年第4期34-40,共7页
在国际电信联盟曾使用的信息通信技术(ICT)发展指数(IDI)基础上,提出改进的信息通信技术发展指数。通过分析2007—2020年二十国集团(G20)的19个成员国的IDI指数和ICT相关指标揭示了G20成员国在信息通信技术发展方面的特点和差异性。分... 在国际电信联盟曾使用的信息通信技术(ICT)发展指数(IDI)基础上,提出改进的信息通信技术发展指数。通过分析2007—2020年二十国集团(G20)的19个成员国的IDI指数和ICT相关指标揭示了G20成员国在信息通信技术发展方面的特点和差异性。分析发现G20成员国信息通信技术发展水平均有较大幅度的提升,国家之间的信息通信技术发展差距逐渐缩小,但增长速度和发展水平仍存在较大差异;G20成员国中韩国、日本、法国、德国和英国的信息通信技术发展水平最高,美国、加拿大、澳大利亚、沙特阿拉伯和俄罗斯的信息通信技术发展居于G20成员国的中上水平,意大利、阿根廷、中国、巴西、土耳其的发展居于中下水平,墨西哥、南非、印度尼西亚和印度的信息通信技术发展水平较低。 展开更多
关键词 G20 信息化 数字化 信息通信技术发展指数 ICT IDI
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The Impact of the Eastward Propagation of Convective Systems over the Tibetan Plateau on the Southwest Vortex Formation in Summer 被引量:9
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作者 FU Shen-Ming SUN Jian-Hua +1 位作者 ZHAO Si-Xiong LI Wan-Li 《Atmospheric and Oceanic Science Letters》 2010年第1期51-57,共7页
Based on the temperature of the black body (TBB),station observed and NCEP reanalysis data,the impacts of the eastward propagation of convective cloud systems over the Tibetan Plateau on the southwest vortex (SWV) for... Based on the temperature of the black body (TBB),station observed and NCEP reanalysis data,the impacts of the eastward propagation of convective cloud systems over the Tibetan Plateau on the southwest vortex (SWV) formation that occurred at 1800 UTC on 29 June 2003 are analyzed by using the Zwack-Okossi (Z-O) equation to diagnose the thermal and dynamic processes.It is found that,in summer,severe convective activities often occur over the Tibetan Plateau due to the abundant supply of moisture.The convective cloud near the east edge of the plateau could move eastward with a shortwave trough in the westerly.The divergent center that is induced by latent heat release,which is associated with severe convective activities,moves out with the convective cloud and contributes to the low level decompression which is favorable for the formation of plateau edge cyclogenesis (PEC).The Z-O equation indicates that,in this case,the latent heat release and convergence are the two most important factors for SWV formation,which amounts to about 42% and 15% of the term TOTAL,respectively.It is implied that the thermal process effect was more important than the dynamic process during SWV formation. 展开更多
关键词 Tibetan Plateau southwest vortex convective system temperature of the black body latent heat release plateau edge cyclogenesis
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Pilot Study on Drinking Water Advanced Treatment by GAC-MF System 被引量:1
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作者 王欣泽 薛罡 +1 位作者 王宝贞 王琳 《Journal of Donghua University(English Edition)》 EI CAS 2004年第1期135-139,共5页
The pilot performance of the combined GAC-MF membrane process for drinking water advanced treatment was described. In the process of GAC adsorption, under the conditions of 20 min HRT and 6 m/h filtration rate, the re... The pilot performance of the combined GAC-MF membrane process for drinking water advanced treatment was described. In the process of GAC adsorption, under the conditions of 20 min HRT and 6 m/h filtration rate, the removal efficiencies of UV_(254) and trichloromethane could reach 40% and 50% respectively and the UV_(254) and trichloromethane in system effluent was less than 0.015 cm^(-1) and 5μg/L respectively. In the post MF membrane process, MF membrane effectively retained the particles and bacteria in raw water. The effluent turbidity was less than 0.2 NTU and no bacteria were detected at all in permeate. A computer-controlled system was employed to control this system. The membrane operating parameters of backwash interval, duration and flux were studied. The backwash interval of 10-min, 20-min and 60-min was researched respectively, and the variation of trans-membrane pressure was also analyzed. Consequently short backwash interval was recommended under the same water consume. 展开更多
关键词 granular activated carbon adsorption MF membrane drinking water advanced treatment
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Devising an Organized Procedure for Effective Risk Management in Independent Water and Power Plant Projects in Saudi Arabia
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作者 Yousef Saad Alsulaiman 《Journal of Civil Engineering and Architecture》 2015年第12期1399-1405,共7页
Worldwide countries are striving to meet demands for water and power, which have been estimated as likely to increase at a rate of 7% per annum over the coming decade. Water and power plant projects following the IWPP... Worldwide countries are striving to meet demands for water and power, which have been estimated as likely to increase at a rate of 7% per annum over the coming decade. Water and power plant projects following the IWPP (independent water and power plant) approach have typically involved a plethora of risks. Since about 75% of the IWPP projects in SA (Sandi Arabia) have failed to meet specified objectives, effective RM (risk management) implementation is key to the success of any public and private project. Practitioners have related their experience about RM in IWPP projects in SA through semi-structured interviews, and analyzed these through the grounded theory approach to identify the elements leading to ineffectiveness when implementing RM in IWPP projects in SA. This study gathers and collates data to present findings in a propositional diagram that is fully grounded, based on practitioners' experiences that extend to the ineffectiveness of implementing RM in water and power projects, specifically in IWPP projects in SA. Findings indicate that IWPP parties have implemented RM in an informal way. In addition, there is a general lack of RM knowledge in the SA water and power industry. The paper concludes with an emergent diagram illustrating major phenomena, categories and subcategories affecting the implementation of RM in IWPP projects in SA. 展开更多
关键词 IWPP project RISK Saudi Arabia water and power.
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Breeding of New Japonica-indica Hybrid Rice Combination Chunyou 59 被引量:9
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作者 WU Ming-guo LIN Jian-rong +1 位作者 SONG Xin-wei RUAN Guan-hai 《Agricultural Science & Technology》 CAS 2011年第8期1139-1140,1143,共3页
Chunyou 59 is a japonica-indica hybrid rice combination developed from Chunjiang 16A(a late japonica CMS line with dwarfness and early anthesis time)and CH59(an indicaclinous wide compatibility restorer line).It has t... Chunyou 59 is a japonica-indica hybrid rice combination developed from Chunjiang 16A(a late japonica CMS line with dwarfness and early anthesis time)and CH59(an indicaclinous wide compatibility restorer line).It has the characteristics of strong heterosis,strong stem,good lodging resistance,large panicles,good cold tolerance,high yield and wide adaptability.It was registered and released by Jiangxi Provincial Crop Variety Appraisal Committee in March 2009.The breeding procedure,characteristics,major techniques of cultivation and seed production of Chunyou 59 were introduced in the paper. 展开更多
关键词 Japonica-indica hybrid rice Chunyou 59 Lodging resistance BREEDING
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A Proposal for Reservoir Volume Calculation in Rainwater Harvesting Systems
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作者 Rodrigo Braga Moruzzi Marcelo Loureiro Garcia Samuel Conceicao de Oliveira 《Journal of Civil Engineering and Architecture》 2012年第6期707-714,共8页
This paper introduces a proposal for reservoir volume calculation in rainwater harvesting systems. The proposed method can be used for reservoir volume design in rainwater harvesting systems and is based on three impo... This paper introduces a proposal for reservoir volume calculation in rainwater harvesting systems. The proposed method can be used for reservoir volume design in rainwater harvesting systems and is based on three important variables. These variables are water demand, system efficiency and repayment time. Several simulations were carried out in different scenarios considering typical values of both catchment area (for low-income and medium-income households) and water demand, with fixed water and tank costs. Results showed that the integrated analysis of demand, efficiency and repayment time may assist designers to determine a more adequate reservoir volume. 展开更多
关键词 Rainwater use reservoir volume design criteria.
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The Financial Structure of Italian Companies 被引量:1
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作者 Carmelo Intrisano 《Chinese Business Review》 2012年第8期748-759,共12页
The choice of capital structure by firms is a recurring topic of corporate finance and evolving on a theoretical and empirical level. On a theoretical level, scholars propose variations to the models by removing the t... The choice of capital structure by firms is a recurring topic of corporate finance and evolving on a theoretical and empirical level. On a theoretical level, scholars propose variations to the models by removing the theoretical hypothesis or expanding variables considered, likewise, on an empirical level, researchers provide survey, which contributions aimed at increasing the understanding of the phenomenon as a whole, considering the possible events in the variety and variability of firms. In particular, one of the most debated topics in the literature regards the existence or absence of relationship between the choices of financial structure and firm value, or the determination of an optimal leverage for the value. Therefore, the attention of researchers has focused on the identification of relationship between debt and equity that maximizes firm's performance and meet shareholders' expectations in terms of return on capital employed for the same risk. Hence, the aim of this paper is to provide another piece to the cognitive complexity of the phenomenon, focusing the research on Italian firms, given the importance of leverage in the financial structure of Italian firms. The methodology used is based on the analysis conducted using the Mediobanca database aggregated sector by sector to identify the main determinants of financial structure. The conclusion is that it is not possible to say with certainty which financial structure theory better represents the behavior of Italian firms concerning financial structure. 展开更多
关键词 choice of financial structure debt financial firm value tax shield tangible assets coverage interest
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Climate Change and Water Resources: Strategies and Practices for Improved Water Management in Arid Countries
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作者 B. S. Choudri Mushtaque Ahmed 《Journal of Agricultural Science and Technology(A)》 2012年第3期335-344,共10页
Assessment report of the Intergovernmental Panel on Climate Change (IPCC) highlighted the complex linkages between climate change and water. The likely warmer climate induced by the climate change is set to alter hy... Assessment report of the Intergovernmental Panel on Climate Change (IPCC) highlighted the complex linkages between climate change and water. The likely warmer climate induced by the climate change is set to alter hydrological cycle and the shifting pattern of the rainfall would affect the spatial and temporal distribution of runoff, soil moisture, and surface and groundwater reserves. Therefore, there is an urgent need to assess the impacts of climate change on water and devise adaptation measures including management structures and processes by which one can deal with this challenge. The paper highlights with the global overview of climate change impacts on water in the arid region, supported and substantiated through scientific evidence drawn from IPCC reports and other relevant documents. This paper provides an overview of water resource management challenges including transboundary geopolitical concerns documented across the world and emphasizes the importance of an integrated framework for adaptive policy making. Further, it examines the viable water resource management options for various sectors and regions and showcases some of the international best practices in adaptation and mitigation. The paper also explains the complementary role of traditional knowledge in coping with climate change risks and uncertainties and the need for a balanced view in designing adaptation and mitigation strategies. 展开更多
关键词 Climate change RAINFALL water resource management adaptation.
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Development and Missions of Unmanned Surface Vehicle 被引量:73
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作者 严汝建 庞硕 +1 位作者 孙寒冰 庞永杰 《Journal of Marine Science and Application》 2010年第4期451-457,共7页
The navy and other Department of Defense organizations are increasingly interested in the use of unmanned surface vehicles (USVs) for a variety of missions and applications. The term USV refers to any vehicle that ope... The navy and other Department of Defense organizations are increasingly interested in the use of unmanned surface vehicles (USVs) for a variety of missions and applications. The term USV refers to any vehicle that operates on the surface of the water without a crew. USVs have the potential, and in some cases the demonstrated ability, to reduce risk to manned forces, provide the necessary force multiplication to accomplish military missions, perform tasks which manned vehicles cannot, and do so in a way that is affordable for the navy. A survey of USV activities worldwide as well as the general technical challenges of USVs was presented below. A general description of USVs was provided along with their typical applications. The technical challenges of developing a USV include its intelligence level, control, high stability, and developmental cost reduction. Through the joint efforts of researchers around the world, it is believed that the development of USVs will enter a new phase in the near future, as USVs could soon be applied widely both in military and civilian service. 展开更多
关键词 unmanned surface vehicle littoral combat ship surveillance and reconnaissance unmanned combat system mine countermeasures
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Financial Level of Czech and Slovak Employees
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作者 Diana Bilkova 《Journal of Modern Accounting and Auditing》 2015年第1期41-50,共10页
This paper deals with the development of wage distribution by gender in the Czech and Slovak Republics in the years of 2005-2012. Special attention is given to changes in the behavior of wage distribution in relation ... This paper deals with the development of wage distribution by gender in the Czech and Slovak Republics in the years of 2005-2012. Special attention is given to changes in the behavior of wage distribution in relation to the onset of the global economic recession. The different behavior of the wage distribution of Czech and Slovak employees during the period is the subject of research. The article discusses the differences in the wage level between men and women in the Czech and Slovak Republics. There are the total wage distributions of men and women together, both in the Czech Republic and in the Slovak Republic on one hand, and wage distributions according to the gender separately for men and women on the other hand. Special attention was paid to the development of Gini coefficient of the concentration in both countries according to the gender in the period under review, too. 展开更多
关键词 wage distribution by gender financial crisis wages of Czech and Slovak employees Gini coefficient ofconcentration forecasts of wage distribution
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The Earth-Diver: Hungarian Variants of the Myth of the Dualistic Creation of the World--Pearls in the Primeval Sea of World Creation
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作者 Attila Mateffy 《Sociology Study》 2014年第5期423-437,共15页
In this paper, the author shall deal with the Hungarian variants of dualistic world creation myths. The aim of this paper is to shed some light on the nature of the connection between the Central-East European Hungari... In this paper, the author shall deal with the Hungarian variants of dualistic world creation myths. The aim of this paper is to shed some light on the nature of the connection between the Central-East European Hungarian and South-East European Romanian and Bulgarian myth variants. The Hungarian pieces are the westernmost variants of the dualistic creation myth-group. Geographically, they stand close to the Romanian variants, but the serious motivational differences between the Romanian and Hungarian variants show that the descent of the two oral narrative groups are distinct, Both the Hungarian and the Romanian variants show similarities with the Bulgarian world creation myths, however, geographically they do not relate tightly. This is why a possible explanation of these correlations is, that the Hungarian and the Bulgarian myths have common Central Eurasian, South-Eastern Siberian origins, upon which starting from the sixth to the seventh centuries the super strata of various gnostic influences have settled. 展开更多
关键词 Comparative folklore oral tradition culture contact dualistic cosmogony Greater Khorasan
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Underwater Recording and 3D Modeling during a Dive Training Course: A Case Study at Panormos, Skopelos, Greece
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作者 Kimon Papadimitriou Anastasios Ktistis Ioanna Sarakinou 《Journal of Environmental Science and Engineering(A)》 2015年第9期445-454,共10页
In the field of underwater survey, there is a variety of methods which differ from each other in terms of the operating environment and the purpose that each method is used. Hence, some of the state-of-the-art methods... In the field of underwater survey, there is a variety of methods which differ from each other in terms of the operating environment and the purpose that each method is used. Hence, some of the state-of-the-art methods, that have many applications in the various scientific fields nowadays, are introduced in this paper. Additionally, the application of the procedures for an underwater survey in shallow depths is analyzed in accordance with the training standards of the PADI Underwater Survey Diver distinctive specialty. The main goal is to demonstrate not only the theoretical background of underwater surveys but also their operational issues, in order to facilitate the development of knowledge and skills during a training course. Finally, a case study for the recording and 3D modeling of the seabeds' morphology in shallow water is presented as it has been organized and accomplished by the participants of such a training course. By this way, it is expected that the reader will understand explicitly the application of the procedures prior, during and after the dive for an underwater survey in shallow depths. 展开更多
关键词 Underwater survey training course PHOTOGRAMMETRY 3D modeling.
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Community-based flood disaster management for older adults in southern of Thailand:A qualitative study
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作者 Pairin Yodsuban Khanitta Nuntaboot 《International Journal of Nursing Sciences》 CSCD 2021年第4期409-417,I0004,共10页
Objective:This study explored the approaches for community-based flood disaster management for older adults in Southern Thailand.It sought to understand community culture for supporting older adults and promoting comm... Objective:This study explored the approaches for community-based flood disaster management for older adults in Southern Thailand.It sought to understand community culture for supporting older adults and promoting community strength in case of flood disaster.Method:This was a qualitative content analysis study using data from observation,in-depth interviews,secondary data,and focus group discussion.One hundred and twenty-seven people in total were selected specifically for the study,including Local Administration Organization(LAO),community leaders,public sector officers,civil groups,and older adult groups and family caregivers.Results:The results of this study were two main themes,focusing on 1)approaches to community-based flood disaster management for older adults as follows:eight approaches in the phase of prevention and preparedness in flood disaster management for older adults,eight approaches in the phase of response in flood disaster management for older adults,and six approaches in the phase of recovery and rehabilitation in flood disaster management for older adults;and 2)factors contributing to success in flood disaster management for older adults has four factors,including the human factor,the work factor,the data factor,and the resource factor.Conclusion:The findings showed significant roles in improving the potential and strength in communitybased flood disaster management for older adults and providing suggestions for community nurses and health practice personnel involving in flood disaster management to mitigate the potential influence on older adults in the community. 展开更多
关键词 Community networks DISASTERS Floods Health personnel Health services Older adult
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Analysis on the multi-phase flow characterization in cross-measure borehole during coal hydraulic slotting 被引量:2
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作者 Chunshan Zheng Baiquan Lin +3 位作者 Mehmet S.Kizil Saiied M.Aminossadati He Li Zhongwei Chen 《International Journal of Mining Science and Technology》 EI CSCD 2018年第4期692-696,共5页
Hydraulic slotting in a gas drainage borehole is an effective method of enhancing gas drainage perfor- mance. However, it frequently occurs that a large amount of slotting products (mainly the coal slurry and gas) i... Hydraulic slotting in a gas drainage borehole is an effective method of enhancing gas drainage perfor- mance. However, it frequently occurs that a large amount of slotting products (mainly the coal slurry and gas) intensely spurt out of the borehole during the slotting, which adversely affects the slotting efficiency. Despite extensive previous investigations on the mechanism and prevention-device design of the spurt during ordinary borehole drilling, a very few studies has focused on the spurt in the s Ottlng pro ] " _ cess. The slotting spurt is mainly caused by two reasons: the coal and gas outburst in the borehole and the borehole deslagging blockage. This paper focuses on the second reason, and investigates the hydraulic deslagging flow patterns in the annular space between the drill pipe and borehole wall Results show that there are six deslagging flow patterns when the drill pipe is still: pure slurry flow, pure gas flow, bubble flow, intermittent flow, layering flow and annular flow. When the drill pipe rotates, each of those six flow patterns changes due to the Taylor vortex effect. Outcomes of this study could help to better understand the slotting-spurt mechanism and provide guidance on the anti-spurt strategies through eliminating the borehole deslagging blockage. 展开更多
关键词 Coal hydraulic slotting Cross-measure borehole Borehole spurt Deslagging flow pattern
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Nutritional Knowledge and Behavior of Professional Athletes in Khorramabad
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作者 Mahnaz Mardani Behzad Bazgir +2 位作者 Akram Beigi Bazgir Hossein Mansumezhad Maryam Rezapour 《Journal of Life Sciences》 2017年第2期65-73,共9页
Today it is proved that the lack of adequate nutritional knowledge leads to problems such as obesity, overweight and increased cardiovascular diseases. However, many obstacles such as poor financial support, lack of t... Today it is proved that the lack of adequate nutritional knowledge leads to problems such as obesity, overweight and increased cardiovascular diseases. However, many obstacles such as poor financial support, lack of time and poor nutritional knowledge can influence achievement of optimal nutrition which is proportional to the level of the athlete's physical activity. The purpose of this study was to determine the level of nutritional knowledge and dietary behavior of athletes in Khorramabad in 2013. Professional athletes of Khorramabad, Iran, with more than one year of regular exercise and at least one course participating in national championships competitions were studied in this cross-sectional, descriptive-analytic study. The samples included 247 athletes aged 17-29 years. Their nutritional knowledge and behavior were measured by the nutritional knowledge and behavior inventory. Results: The results showed a significant difference in nutritional knowledge of athletes by gender and educational level; female athletes have higher nutritional knowledge than male athletes. A gender-dependent difference was found in nutritional behavior; despite their higher nutritional knowledge, female athletes have weaker nutritional behavior than male athletes. However, no significant correlation was found between BMI and nutritional knowledge and behavior of the athletes. Moreover, findings showed that nutritional knowledge and behavior could be significantly different in various sports. 展开更多
关键词 SPORTS nutritional knowledge nutritional behavior Khorramabad.
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Temperature Inversion in the Bay of Bengal Prior to the Summer Monsoon Onsets in 2010 and 2011 被引量:4
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作者 LI Jian YANG Lei +1 位作者 SHU Ye-Qiang WANG Dong-Xiao 《Atmospheric and Oceanic Science Letters》 2012年第4期290-294,共5页
Freshwater input such as runoff and rainfall can enhance stratification in the Bay of Bengal(BOB) through the formation of a "barrier layer",which can lead to the formation of a temperature inversion.The aut... Freshwater input such as runoff and rainfall can enhance stratification in the Bay of Bengal(BOB) through the formation of a "barrier layer",which can lead to the formation of a temperature inversion.The authors focused on the temperature inversion in spring,especially before the onset of the summer monsoon,because previous research has mainly focused on the temperature inversion in winter.Using the hydrographic data from two cruises performed during 24-30 April 2010 and 1-4 May 2011,the authors found that inversions appeared at two out of nine Conductivity-Temperature-Depth Recorder(CTD) stations across the 10°N section and at seven out of 13 CTD stations across the 6°N section in the BOB.In 2010,the inversions(at stations N02 and N05) occurred at depths of approximately 50-60 meters,and their formation was caused by the advection of cold water over warm water.In 2010,the N02 inversion was mainly influenced by the warm saline water from the east sinking below the cold freshwater from the west,while the N05 inversion was affected by the warm saline water from its west sinking below the cold freshwater from its east.In 2011,the inversions appeared at depths of 20-40 meters(at stations S01,S02,S07,S08,and S09) and near 50 m(S12 and S13).The inversions in 2011 were mainly caused by the net heat loss of the ocean along the 6°N section. 展开更多
关键词 temperature inversion heat flux lateral ad- vection barrier layer STRATIFICATION FRESHWATER
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Changes of Atmospheric Water Balance over China under the IPCC SRES A1B Scenario Based on RegCM3 Simulations
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作者 SUN Bo JIANG Da-Bang 《Atmospheric and Oceanic Science Letters》 2012年第6期461-467,共7页
Simulations of the Regional Climate Model Version 3 (RegCM3) under the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) A1B scenario were employed to investigate possible d... Simulations of the Regional Climate Model Version 3 (RegCM3) under the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) A1B scenario were employed to investigate possible decadal changes and long-term trends of annual mean atmospheric water balance components over China in the 21st century with reference to the period of 1981-2000. An evaluation showed that RegCM3 can reasonably reproduce annual evapotranspiration, precipitation, and water vapor transport over China, with a better performance for March-June. It was found that the water vapor exchange between the land surface and atmosphere would be significantly intensified in Northwest China by the mid-to late-21st century and that the region would possibly shift to a wetter or drought-mitigated state under global warming. Conversely, the water vapor exchange evidently weakened over the Tibetan Plateau and South-west China by the mid-to late-21st century. In addition, there appears to be a drier state for Northeast China and the middle and lower reaches of the Yangtze River valley by the mid-to late-21st century, with slight mitigation by the end compared with the mid-21st century. The westerly and southwesterly water vapor transport over China generally presents an increasing trend, with increasing diver-gence over the Tibetan Plateau and Northeast China, corresponding to a loss of atmospheric water vapor by water vapor transport. 展开更多
关键词 REGCM3 A1B scenario atmospheric water balance
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Genetic Analysis of the P1 Region of Human Enterovirus 71 Strains and Expression of the 55 F StrainVP1 Protein 被引量:2
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作者 Jian-qiang Li Jun-jie Yang +5 位作者 Xiu-juan Fan Zhen-peng Sun Yan Sun Huan Li Zi-xin Meng Wei Li 《Virologica Sinica》 CAS CSCD 2012年第1期10-18,共9页
Enterovirus 71 (EV71) is a member of the Entero-virus genus of the Picomaviridae family and is the major cause of Hand, foot, and mouth disease (HFMD) in children. Different strains from Gansu were cloned and the ... Enterovirus 71 (EV71) is a member of the Entero-virus genus of the Picomaviridae family and is the major cause of Hand, foot, and mouth disease (HFMD) in children. Different strains from Gansu were cloned and the P1 protein was sequenced and analysed. Results indicate that there are three kinds of EV71 infections prevalent in Gansu. The VP 1 protein from one of these strains, 55F, was expressed. The recombinant protein was expressed with high level and reacted specifically with the EV71 patient antibody, the recombinant protein was also applied to raise antiserum in rabbits and after the fourth injection a high titer of antiserum was detected by ELISA assay. These data are useful for further clarification of prevalent EV71 strains in the north of China at the molecular level and provide a basis for EV71 diagnosis. 展开更多
关键词 EV71 Genetic analysis P1 region EXPRESSION VP1 protein
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The effect of sex and performance level on pacing in cross-country skiers:Vasaloppet 2004-2017 被引量:1
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作者 Pantelis Theodoros Nikolaidis Elias Villiger Beat Knechtle 《Journal of Sport and Health Science》 SCIE 2018年第4期453-458,共6页
Background: Pacing, defined as percentage changes of speed between successive splits, has been extensively studied in running and cycling endurance sports; however, less information about the trends in change of spee... Background: Pacing, defined as percentage changes of speed between successive splits, has been extensively studied in running and cycling endurance sports; however, less information about the trends in change of speed during cross-country (XC) ski racing is available. Therefore, the aim of the present study was to examine the effect of performance (quartiles of race time (Q), with Q1 the fastest and Q4 the slowest) level on pacing in the Vasaloppet ski race, the largest XC skiing race in the world. Methods: For this purpose, we analyzed female (n = 19,465) and male (n = 164,454) finishers in the Vasaloppet ski race from 2004 to 2017 using a one-way (2 sexes) analysis of variance with repeated measures to examine percentage changes of speed between 2 successive splits. Overall, the race consisted of 8 splits. Results: The race speeds of Q1, Q2, Q3, and Q4 were 13.6 ± 1.8, 10.6 ± 0.5, 9.2 ± 0.3, and 8.1 ±- 0.4 km/h, respectively, among females and 16.7 ± 1.7, 13.1 ± 0.7, 10.9 ± 0.6, and 8.9 ± 0.7 km/h, respectively, among males. The overall pacing strategy of finishers was variable. A small sex × split interaction on speed was observed (η^2= 0.016, p 〈 0.001), with speed difference between sexes ranging from 14.9% (Split 7) to 27.0% (Split 1) and larger changes in speed between 2 successive splits being shown for females (p 〈 0.001, η^2=0.004). A large performance × split interaction on speed, with Q1 presenting the smallest changes of speed between splits, was shown for females (η^2= 0.149, p 〈 0.001) and males (η^2 = 0.169,p 〈 0.001). Conclusion: Male and fast XC skiers are more even pacers. Coaches and athletes should develop tailored sex- and performance-level pacing strategies; for instance, they should advise fast XC skiers to start fast and maintain their speed, rather than starting slowly and trying to make up time by going faster at times during the race.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 Endurance exercise Race speed SEX Sport performance Winter sport
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Use of Chemical Admixtures to Modify the Rheological Behavior of Cementitious Systems Containing Manufactured Aggregates
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作者 Ara Avedis Jeknavorian Eric Koehler 《Journal of Civil Engineering and Architecture》 2012年第10期1263-1272,共10页
The use of local materials is an important part of sustainability for the concrete industry. The declining availability of aggregate resources in many areas has the potential to result in the use of alternative aggreg... The use of local materials is an important part of sustainability for the concrete industry. The declining availability of aggregate resources in many areas has the potential to result in the use of alternative aggregates of lower quality, which can require higher cementitious materials contents, or the use of aggregates shipped from greater distance. In some markets, manufactured sands are replacing natural sands, which can adversely impact the rheology of cementitious mixtures. The use of certain chemical admixtures has been found to often minimize the need to increase cement and water contents in order to overcome the loss of workability that can accompany aggregate sources which feature flat, elongated, angular, and rough particles. In this study, a wide range of natural and manufactured sands were characterized for gradation, mineralogy, shape, texture, and cleanliness, and also evaluated for their effect on mortar rheology with and without a VMA (viscosity modifying agent) type chemical admixture. Use of the VMA is shown to mitigate the rheological effect of certain sands, and in some cases can allow for optimizing the mixture to lower paste contents. In the case of PCP (polycarboxylate)-based superplasticizers, attention is drawn to the increased dose required to achieve target workability versus superplasticizers based on NSFC (naphthalene sulfonate condensate) when swellable clays are present in the very fine fraction of certain aggregate sources. The use of sands with higher fines contents are also shown to increase the workability provided the fines are of appropriate quality. 展开更多
关键词 Manufactured aggregate natural aggregate RHEOLOGY viscosity modifying agent
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