Ensemble forecasting has become the prevailing method in current operational weather forecasting. Although ensemble mean forecast skill has been studied for many ensemble prediction systems（EPSs） and different cases...Ensemble forecasting has become the prevailing method in current operational weather forecasting. Although ensemble mean forecast skill has been studied for many ensemble prediction systems（EPSs） and different cases, theoretical analysis regarding ensemble mean forecast skill has rarely been investigated, especially quantitative analysis without any assumptions of ensemble members. This paper investigates fundamental questions about the ensemble mean, such as the advantage of the ensemble mean over individual members, the potential skill of the ensemble mean, and the skill gain of the ensemble mean with increasing ensemble size. The average error coefficient between each pair of ensemble members is the most important factor in ensemble mean forecast skill, which determines the mean-square error of ensemble mean forecasts and the skill gain with increasing ensemble size. More members are useful if the errors of the members have lower correlations with each other, and vice versa. The theoretical investigation in this study is verified by application with the T213 EPS. A typical EPS has an average error coefficient of between 0.5 and 0.8; the 15-member T213 EPS used here reaches a saturation degree of 95%（i.e., maximum 5% skill gain by adding new members with similar skill to the existing members） for 1–10-day lead time predictions, as far as the mean-square error is concerned.展开更多
The popularity of flexible working hours around the world has slowed down the historical trend of reducing working hours.It even shows signs of regression.Whether and how to guide the cur-rent society with flexible wo...The popularity of flexible working hours around the world has slowed down the historical trend of reducing working hours.It even shows signs of regression.Whether and how to guide the cur-rent society with flexible working hours to return to the historical track of reducing working hours,improve the quality of working hours,and promote a smooth transition from the era of traditional standard work-ing hours to the era of flexible working hours has become a question related to the legal regulation of working hours in the new era.In this regard,although Western countries have proposed new regulatory concepts and carried out legislative practices with distinctive charac-teristics,the limitations of legal regulation capabilities have prevented them from proposing a package of institutional solutions.The advan-tage of China in the ability of legal regulation of working hours has been gradually formed in the legislation on working hours unnder the leadership of the CPC in the past century.It enables China to break through the limitations of the West and propose a Chinese approach to answer the question of the legal regulation of working hours in the new era from three aspects:limiting the extension of working hours,improving the quality of flexible working hours,and optimizing the funnctions of the multi-funnctional regulatory system for working hours.展开更多
This article, the purpose of which is to deal with some problems in studying and teaching English, is merely for the students of English to read, who have just entered the second year at a foreign languages institute....This article, the purpose of which is to deal with some problems in studying and teaching English, is merely for the students of English to read, who have just entered the second year at a foreign languages institute. When teaching the second-year students, I have often been asked this awkward question: "What do you think is the correct way to study English?" It took me quite a time to answer it. Now after many years of teaching I think I have some ideas on this subject.展开更多
This research on the attenuation features of intensity in the Yunnan region has been conducted by using intensity isoseismals of 127 earthquakes, and the following three conclusions have been put forward: (1) The aver...This research on the attenuation features of intensity in the Yunnan region has been conducted by using intensity isoseismals of 127 earthquakes, and the following three conclusions have been put forward: (1) The average ratio value of long axis to short axis of innermost isoseismals in the Yunnan region is larger than that of eastern China and smaller than that of western China. The velocity of intensity attenuation varies in different directions; (2) The zoning feature of intensity attenuation in the Yunnan region is obvious; (3) In Northwest China and North China, the ratios of long axis to short axis of low magnitude isoseismals are larger than those of high magnitude ones. Compared with that phenomenon, the ratios in the Yunnan region are more complicated. Finally, some relevant questions are discussed.展开更多
为了促进人们对语篇语义、信息结构前沿的了解,介绍当前待议问题(Question under discussion, QUD)的理论要点,并利用典例阐释其在理论研究和实证研究上的运用方法,最后结合QUD的优势和不足讨论其在汉语中运用的广泛空间。研究发现:首先...为了促进人们对语篇语义、信息结构前沿的了解,介绍当前待议问题(Question under discussion, QUD)的理论要点,并利用典例阐释其在理论研究和实证研究上的运用方法,最后结合QUD的优势和不足讨论其在汉语中运用的广泛空间。研究发现:首先,QUD与选项语义学、询问语义学相结合,能够消解受语境限制选项集模糊的问题,起到增强理论解释力、拓展理论解释范围的效果;其次,QUD为实验研究和自然语言处理提供了新工具,相关研究揭示了语篇信息结构对语言习得的作用,推动了语篇信息结构层面语料标注的发展;最后,QUD能够为汉语现象提供新的解决思路,促进人们挖掘语言事实背后所蕴含的深刻道理。展开更多
基金supported by the National Basic Research (973) Program of China (Grant No. 2013CB430106)the R&D Special Fund for Public Welfare Industry (Meteorology) (Grant Nos. GYHY201306002 and GYHY201206005)+2 种基金the National Natural Science Foundation of China (Grant Nos. 40830958 and 41175087)the Jiangsu Collaborative Innovation Center for Climate Changethe High Performance Computing Center of Nanjing University
文摘Ensemble forecasting has become the prevailing method in current operational weather forecasting. Although ensemble mean forecast skill has been studied for many ensemble prediction systems（EPSs） and different cases, theoretical analysis regarding ensemble mean forecast skill has rarely been investigated, especially quantitative analysis without any assumptions of ensemble members. This paper investigates fundamental questions about the ensemble mean, such as the advantage of the ensemble mean over individual members, the potential skill of the ensemble mean, and the skill gain of the ensemble mean with increasing ensemble size. The average error coefficient between each pair of ensemble members is the most important factor in ensemble mean forecast skill, which determines the mean-square error of ensemble mean forecasts and the skill gain with increasing ensemble size. More members are useful if the errors of the members have lower correlations with each other, and vice versa. The theoretical investigation in this study is verified by application with the T213 EPS. A typical EPS has an average error coefficient of between 0.5 and 0.8; the 15-member T213 EPS used here reaches a saturation degree of 95%（i.e., maximum 5% skill gain by adding new members with similar skill to the existing members） for 1–10-day lead time predictions, as far as the mean-square error is concerned.
基金funded by the National Social Science Fund of China (Western Region Program)“Research on Improving the Quality of Legislation in China on Rest and Vacation from a Global Perspective”(Project Approval Number:19XFX014)。
文摘The popularity of flexible working hours around the world has slowed down the historical trend of reducing working hours.It even shows signs of regression.Whether and how to guide the cur-rent society with flexible working hours to return to the historical track of reducing working hours,improve the quality of working hours,and promote a smooth transition from the era of traditional standard work-ing hours to the era of flexible working hours has become a question related to the legal regulation of working hours in the new era.In this regard,although Western countries have proposed new regulatory concepts and carried out legislative practices with distinctive charac-teristics,the limitations of legal regulation capabilities have prevented them from proposing a package of institutional solutions.The advan-tage of China in the ability of legal regulation of working hours has been gradually formed in the legislation on working hours unnder the leadership of the CPC in the past century.It enables China to break through the limitations of the West and propose a Chinese approach to answer the question of the legal regulation of working hours in the new era from three aspects:limiting the extension of working hours,improving the quality of flexible working hours,and optimizing the funnctions of the multi-funnctional regulatory system for working hours.
文摘This article, the purpose of which is to deal with some problems in studying and teaching English, is merely for the students of English to read, who have just entered the second year at a foreign languages institute. When teaching the second-year students, I have often been asked this awkward question: "What do you think is the correct way to study English?" It took me quite a time to answer it. Now after many years of teaching I think I have some ideas on this subject.
基金Sortoftheproject:fundedbytheNaturalScientificFoundationofYunnanProvince (2 0 0 0D0 0 2 8Q) China .
文摘This research on the attenuation features of intensity in the Yunnan region has been conducted by using intensity isoseismals of 127 earthquakes, and the following three conclusions have been put forward: (1) The average ratio value of long axis to short axis of innermost isoseismals in the Yunnan region is larger than that of eastern China and smaller than that of western China. The velocity of intensity attenuation varies in different directions; (2) The zoning feature of intensity attenuation in the Yunnan region is obvious; (3) In Northwest China and North China, the ratios of long axis to short axis of low magnitude isoseismals are larger than those of high magnitude ones. Compared with that phenomenon, the ratios in the Yunnan region are more complicated. Finally, some relevant questions are discussed.
文摘为了促进人们对语篇语义、信息结构前沿的了解,介绍当前待议问题(Question under discussion, QUD)的理论要点,并利用典例阐释其在理论研究和实证研究上的运用方法,最后结合QUD的优势和不足讨论其在汉语中运用的广泛空间。研究发现:首先,QUD与选项语义学、询问语义学相结合,能够消解受语境限制选项集模糊的问题,起到增强理论解释力、拓展理论解释范围的效果;其次,QUD为实验研究和自然语言处理提供了新工具,相关研究揭示了语篇信息结构对语言习得的作用,推动了语篇信息结构层面语料标注的发展;最后,QUD能够为汉语现象提供新的解决思路,促进人们挖掘语言事实背后所蕴含的深刻道理。
