反中子阱型研究堆独特的堆芯和反射层结构对传统上适用于动力堆的确定论堆芯物理计算方法提出了挑战。使用确定论程序DRAGON/DONJON对反中子阱型设计的中国先进研究堆(China Advanced Research Reactor,CARR)进行了堆芯物理计算与适用...反中子阱型研究堆独特的堆芯和反射层结构对传统上适用于动力堆的确定论堆芯物理计算方法提出了挑战。使用确定论程序DRAGON/DONJON对反中子阱型设计的中国先进研究堆(China Advanced Research Reactor,CARR)进行了堆芯物理计算与适用性分析。采用了多组件方法改善CARR堆芯组件均匀化计算的环境影响;使用OPTEX反射层优化方法对反射层均匀化群常数进行修正。将蒙特卡罗方法的计算结果作为参考解,使用DRAGON程序挂载几种常用的多群截面库进行组件计算,选择偏差最小的SHEM-295作为CARR堆芯物理计算截面库。将DRAGON/DONJON的计算结果与传统“三步法”和参考解进行对比表明:临界工况附近的有效增殖系数keff、堆芯活性区和重水箱中间位置的热中子注量率分布以及标准燃料组件的功率分布等核特性参数偏差较小。对于堆芯与重水箱交界、水池外真空边界、跟随体组件等处计算结果出现较大偏差的原因进行了分析。证明了使用DRAGON/DONJON程序进行CARR物理计算具备可行性且相较于传统“三步法”计算精度有了明显改善,能够满足CARR堆上实验方案设计、运行参数快速计算分析等需求。展开更多
‘Dragon king’theory of extreme events has been systematically proposed and discussed since 2012,the last‘year of dragon’in the Chinese lunar calendar(Sornette and Ouillon,2012;Yukalov and Sornette,2012;Sachs et al...‘Dragon king’theory of extreme events has been systematically proposed and discussed since 2012,the last‘year of dragon’in the Chinese lunar calendar(Sornette and Ouillon,2012;Yukalov and Sornette,2012;Sachs et al.,2012),and has been under discussion till present(e.g.,Eliazar,2017;Lin et al.,2018;Glette-Iversen and Aven,2021;Premraj et al.,2021;Lei et al.,2023).In this theoretical framework based on the physics of complexity,a‘dragon king’is defined as an event so extreme that it lies outside a power-law distribution.What is of special interest is that,according to its theory,a‘dragon king’event should pose significant predictability(Sornette and Ouillon,2012).As the next‘year of dragon’approaches soon,it is worth revisiting this concept.展开更多
In open pit mining,uncontrolled block instabilities have serious social,economic and regulatory consequences,such as casualties,disruption of operation and increased regulation difficulties.For this reason,bench face ...In open pit mining,uncontrolled block instabilities have serious social,economic and regulatory consequences,such as casualties,disruption of operation and increased regulation difficulties.For this reason,bench face angle,as one of the controlling parameters associated with block instabilities,should be carefully designed for sustainable mining.This study introduces a discrete fracture network(DFN)-based probabilistic block theory approach for the fast design of the bench face angle.A major advantage is the explicit incorporation of discontinuity size and spatial distribution in the procedure of key blocks testing.The proposed approach was applied to a granite mine in China.First,DFN models were generated from a multi-step modeling procedure to simulate the complex structural characteristics of pit slopes.Then,a modified key blocks searching method was applied to the slope faces modeled,and a cumulative probability of failure was obtained for each sector.Finally,a bench face angle was determined commensurate with an acceptable risk level of stability.The simulation results have shown that the number of hazardous traces exposed on the slope face can be significantly reduced when the suggested bench face angle is adopted,indicating an extremely low risk of uncontrolled block instabilities.展开更多
Dragon is a traditional totem of the Chinese nation and is worshiped by the Chinese people all over the world,representing auspiciousness,strength and wisdom.China has a vast territory.As for the rich and diverse inta...Dragon is a traditional totem of the Chinese nation and is worshiped by the Chinese people all over the world,representing auspiciousness,strength and wisdom.China has a vast territory.As for the rich and diverse intangible cultural heritage,there are many cultural treasures directly related to"dragon",and fire dragon dance is one of them.展开更多
My journey to Zhongshan City in Guangdong Province alongside experts,foreign correspondents,and local Chinese journalists proved to be an enlightening exploration of the intricacies of China’s development,especially ...My journey to Zhongshan City in Guangdong Province alongside experts,foreign correspondents,and local Chinese journalists proved to be an enlightening exploration of the intricacies of China’s development,especially within its smaller cities.While a brief five-day sojourn wasn’t sufficient for intimacy with the city’s entirety,the immersion into Zhongshan’s cultural,historical,and modern facets,including Zhongshan Museum,urban planning zones,business hubs,an industrial park,ancient villages,Dr.Sun Yat-sen Museum,and a monumental bridge project,left me with the impression that the city is awakening like a dragon ascending from the heart of Guangdong.展开更多
Blasting is a cost-effective technique to break hard rock volumes by using explosives in the mining and civil engineering realms. Moreover, although blasting is a designed process and plays an indispensable role in th...Blasting is a cost-effective technique to break hard rock volumes by using explosives in the mining and civil engineering realms. Moreover, although blasting is a designed process and plays an indispensable role in these industries, it can also have multiple adverse environmental impacts. One such effect is flyrock, which poses risks to nearby machinery, and residential structures, and can even lead to injuries or fatalities. To optimize blasting efficiency as well as restrict side effects, prediction of the blast aftereffects is vital. Therefore, the present work focuses on using two machine learning methods to predict the velocity of flyrock in the open pit mine. To address this issue, a comprehensive dataset was gathered from the open pit mine. Then, Decision Tree and Random Forest algorithms were employed to predict flyrock velocity. The Random Forest model demonstrated superior performance compared to the Decision Tree model. Nonetheless, the performance of the Decision Tree model was deemed satisfactory, as evidenced by its coefficient of determination value of 0.83, mean squared error (MSE) of 4.2, and mean absolute percentage error (MAPE) of 5.6%. Considering these metrics, it is reasonable to conclude that tree-based algorithms can be effective in predicting flyrock velocity.展开更多
Background:The incidence of lumbar disc herniation(LDH)is notably high.Consensus among experts highlights non-surgical treatments as the primary therapeutic approach for LDH.Contemporary medicine frequently employs ph...Background:The incidence of lumbar disc herniation(LDH)is notably high.Consensus among experts highlights non-surgical treatments as the primary therapeutic approach for LDH.Contemporary medicine frequently employs pharmacotherapy and epidural injections in such treatments,which are associated with numerous adverse effects.Prolonged use can severely impair the liver and kidney functions of patients.Hence,the role of safe and effective traditional Chinese medicine techniques becomes pivotal.Among various traditional Chinese medicine approaches for treating LDH,fire dragon cupping,renowned for its remarkable efficacy,cost-effectiveness,and ease of application,is extensively utilised in clinical settings for managing LDH.Nonetheless,there is a scarcity of systematic and standardised evidence from evidence-based medicine studies.Therefore,conducting a meta-analysis is imperative.Methods:A comprehensive computerised search was conducted in databases including China National Knowledge Infrastructure,WanFang Data,VIP,China Biology Medicine disc,PubMed,EMbase,The Cochrane Library,Web of Science,and CINAHL.The search aimed to gather randomised controlled trials on fire dragon cupping therapy for LDH,spanning from the inception of these databases until December 2023.Two researchers independently screened the literature according to inclusion and exclusion criteria,extracted data,and assessed the methodological quality of the studies included,utilising RevMan 5.3 software for meta-analysis.Results:The results show that the fire dragon cupping therapy group had better clinical effectiveness(relative risk=1.23,95%confidence interval(CI)(1.14,1.33),P<0.00001),less pain(standardized mean difference=–1.33,95%CI(–1.49,–1.16),P<0.00001),and some improvement in lumbar function(Japanese Orthopaedic Association scores:mean difference=3.37,95%CI(2.31,4.43),P<0.00001.Conclusion:The fire dragon cupping therapy significantly alleviates LDH,warranting its extensive application.However,considering the limitations in the number and quality of studies included,the aforementioned conclusion necessitates further validation through more high-quality research.展开更多
If you're a sort of human who gets woozy on a step stool,then this story probably isn't for you.On the other hand,if you have a strong stomach and like taking extreme selfies,then the Coiling Dragon Cliff Skyw...If you're a sort of human who gets woozy on a step stool,then this story probably isn't for you.On the other hand,if you have a strong stomach and like taking extreme selfies,then the Coiling Dragon Cliff Skywalk in Hunan Province,China may be the place you want to go.Attached more than 1,400 meters straight up the side of Tianmen Mountain in China's Zhangjiajie City,the Coiling Dragon Cliff Skywalk is almost inconceivable.展开更多
People across China have begun decorating their houses,pasting poetic couplets and auspicious words on the doors,buying new clothes,and getting ready to make dumplings.You guessed right-it’s time to celebrate the Spr...People across China have begun decorating their houses,pasting poetic couplets and auspicious words on the doors,buying new clothes,and getting ready to make dumplings.You guessed right-it’s time to celebrate the Spring Festival,and ring in the Chinese New Year-the Year of the Dragon.展开更多
A dragon year,so I read somewhere,is one in which,individually and collectively,we are filled with energy and confidence.It’s supposed to be a year of transformation,good fortune and prosperity;all of which,it seems ...A dragon year,so I read somewhere,is one in which,individually and collectively,we are filled with energy and confidence.It’s supposed to be a year of transformation,good fortune and prosperity;all of which,it seems to me,is just what the world needs as it continues to shake off the effects of the COVID-19 pandemic.展开更多
文摘反中子阱型研究堆独特的堆芯和反射层结构对传统上适用于动力堆的确定论堆芯物理计算方法提出了挑战。使用确定论程序DRAGON/DONJON对反中子阱型设计的中国先进研究堆(China Advanced Research Reactor,CARR)进行了堆芯物理计算与适用性分析。采用了多组件方法改善CARR堆芯组件均匀化计算的环境影响;使用OPTEX反射层优化方法对反射层均匀化群常数进行修正。将蒙特卡罗方法的计算结果作为参考解,使用DRAGON程序挂载几种常用的多群截面库进行组件计算,选择偏差最小的SHEM-295作为CARR堆芯物理计算截面库。将DRAGON/DONJON的计算结果与传统“三步法”和参考解进行对比表明:临界工况附近的有效增殖系数keff、堆芯活性区和重水箱中间位置的热中子注量率分布以及标准燃料组件的功率分布等核特性参数偏差较小。对于堆芯与重水箱交界、水池外真空边界、跟随体组件等处计算结果出现较大偏差的原因进行了分析。证明了使用DRAGON/DONJON程序进行CARR物理计算具备可行性且相较于传统“三步法”计算精度有了明显改善,能够满足CARR堆上实验方案设计、运行参数快速计算分析等需求。
基金supported by the National Natural Science Foundation of China(NSFC,contract number U2039207 and 41704093).
文摘‘Dragon king’theory of extreme events has been systematically proposed and discussed since 2012,the last‘year of dragon’in the Chinese lunar calendar(Sornette and Ouillon,2012;Yukalov and Sornette,2012;Sachs et al.,2012),and has been under discussion till present(e.g.,Eliazar,2017;Lin et al.,2018;Glette-Iversen and Aven,2021;Premraj et al.,2021;Lei et al.,2023).In this theoretical framework based on the physics of complexity,a‘dragon king’is defined as an event so extreme that it lies outside a power-law distribution.What is of special interest is that,according to its theory,a‘dragon king’event should pose significant predictability(Sornette and Ouillon,2012).As the next‘year of dragon’approaches soon,it is worth revisiting this concept.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.42102313 and 52104125)the Fundamental Research Funds for the Central Universities(Grant No.B240201094).
文摘In open pit mining,uncontrolled block instabilities have serious social,economic and regulatory consequences,such as casualties,disruption of operation and increased regulation difficulties.For this reason,bench face angle,as one of the controlling parameters associated with block instabilities,should be carefully designed for sustainable mining.This study introduces a discrete fracture network(DFN)-based probabilistic block theory approach for the fast design of the bench face angle.A major advantage is the explicit incorporation of discontinuity size and spatial distribution in the procedure of key blocks testing.The proposed approach was applied to a granite mine in China.First,DFN models were generated from a multi-step modeling procedure to simulate the complex structural characteristics of pit slopes.Then,a modified key blocks searching method was applied to the slope faces modeled,and a cumulative probability of failure was obtained for each sector.Finally,a bench face angle was determined commensurate with an acceptable risk level of stability.The simulation results have shown that the number of hazardous traces exposed on the slope face can be significantly reduced when the suggested bench face angle is adopted,indicating an extremely low risk of uncontrolled block instabilities.
文摘Dragon is a traditional totem of the Chinese nation and is worshiped by the Chinese people all over the world,representing auspiciousness,strength and wisdom.China has a vast territory.As for the rich and diverse intangible cultural heritage,there are many cultural treasures directly related to"dragon",and fire dragon dance is one of them.
文摘My journey to Zhongshan City in Guangdong Province alongside experts,foreign correspondents,and local Chinese journalists proved to be an enlightening exploration of the intricacies of China’s development,especially within its smaller cities.While a brief five-day sojourn wasn’t sufficient for intimacy with the city’s entirety,the immersion into Zhongshan’s cultural,historical,and modern facets,including Zhongshan Museum,urban planning zones,business hubs,an industrial park,ancient villages,Dr.Sun Yat-sen Museum,and a monumental bridge project,left me with the impression that the city is awakening like a dragon ascending from the heart of Guangdong.
文摘Blasting is a cost-effective technique to break hard rock volumes by using explosives in the mining and civil engineering realms. Moreover, although blasting is a designed process and plays an indispensable role in these industries, it can also have multiple adverse environmental impacts. One such effect is flyrock, which poses risks to nearby machinery, and residential structures, and can even lead to injuries or fatalities. To optimize blasting efficiency as well as restrict side effects, prediction of the blast aftereffects is vital. Therefore, the present work focuses on using two machine learning methods to predict the velocity of flyrock in the open pit mine. To address this issue, a comprehensive dataset was gathered from the open pit mine. Then, Decision Tree and Random Forest algorithms were employed to predict flyrock velocity. The Random Forest model demonstrated superior performance compared to the Decision Tree model. Nonetheless, the performance of the Decision Tree model was deemed satisfactory, as evidenced by its coefficient of determination value of 0.83, mean squared error (MSE) of 4.2, and mean absolute percentage error (MAPE) of 5.6%. Considering these metrics, it is reasonable to conclude that tree-based algorithms can be effective in predicting flyrock velocity.
基金supported by the 2022 study on the effectiveness of Fire Dragon Cupping in treating cold-dampness obstructive type shoulder stiffness,funded by the Bao'an District Healthcare Research Project in Shenzhen(Shen Bao Ke[2023]No.13,Project No.2022JD237)2023 study on the therapeutic observation and mechanism exploration of Fire Dragon Cupping in cold-dampness obstructive type acute gout,funded by the Guangdong Provincial Administration of Traditional Chinese Medicine(Yue Zhong Yi Han[2023]No.205,Project No.20242077)+1 种基金National Clinical Key Specialty(Traditional Chinese Medicine)Construction Project(2013-239)Sanming Project of Medicine in Shenzhen(No.SZZYSM202206014).
文摘Background:The incidence of lumbar disc herniation(LDH)is notably high.Consensus among experts highlights non-surgical treatments as the primary therapeutic approach for LDH.Contemporary medicine frequently employs pharmacotherapy and epidural injections in such treatments,which are associated with numerous adverse effects.Prolonged use can severely impair the liver and kidney functions of patients.Hence,the role of safe and effective traditional Chinese medicine techniques becomes pivotal.Among various traditional Chinese medicine approaches for treating LDH,fire dragon cupping,renowned for its remarkable efficacy,cost-effectiveness,and ease of application,is extensively utilised in clinical settings for managing LDH.Nonetheless,there is a scarcity of systematic and standardised evidence from evidence-based medicine studies.Therefore,conducting a meta-analysis is imperative.Methods:A comprehensive computerised search was conducted in databases including China National Knowledge Infrastructure,WanFang Data,VIP,China Biology Medicine disc,PubMed,EMbase,The Cochrane Library,Web of Science,and CINAHL.The search aimed to gather randomised controlled trials on fire dragon cupping therapy for LDH,spanning from the inception of these databases until December 2023.Two researchers independently screened the literature according to inclusion and exclusion criteria,extracted data,and assessed the methodological quality of the studies included,utilising RevMan 5.3 software for meta-analysis.Results:The results show that the fire dragon cupping therapy group had better clinical effectiveness(relative risk=1.23,95%confidence interval(CI)(1.14,1.33),P<0.00001),less pain(standardized mean difference=–1.33,95%CI(–1.49,–1.16),P<0.00001),and some improvement in lumbar function(Japanese Orthopaedic Association scores:mean difference=3.37,95%CI(2.31,4.43),P<0.00001.Conclusion:The fire dragon cupping therapy significantly alleviates LDH,warranting its extensive application.However,considering the limitations in the number and quality of studies included,the aforementioned conclusion necessitates further validation through more high-quality research.
文摘If you're a sort of human who gets woozy on a step stool,then this story probably isn't for you.On the other hand,if you have a strong stomach and like taking extreme selfies,then the Coiling Dragon Cliff Skywalk in Hunan Province,China may be the place you want to go.Attached more than 1,400 meters straight up the side of Tianmen Mountain in China's Zhangjiajie City,the Coiling Dragon Cliff Skywalk is almost inconceivable.
文摘People across China have begun decorating their houses,pasting poetic couplets and auspicious words on the doors,buying new clothes,and getting ready to make dumplings.You guessed right-it’s time to celebrate the Spring Festival,and ring in the Chinese New Year-the Year of the Dragon.
文摘A dragon year,so I read somewhere,is one in which,individually and collectively,we are filled with energy and confidence.It’s supposed to be a year of transformation,good fortune and prosperity;all of which,it seems to me,is just what the world needs as it continues to shake off the effects of the COVID-19 pandemic.
