In 2024,the Chinese Meridian Project(CMP)completed its construction,deploying 282 instruments across 31 stations.This achievement not only provides a robust foundation but also serves as a reference template for the I...In 2024,the Chinese Meridian Project(CMP)completed its construction,deploying 282 instruments across 31 stations.This achievement not only provides a robust foundation but also serves as a reference template for the International Meridian Circle Program(IMCP).The IMCP aims to integrate and establish a comprehensive network of ground-based monitoring stations designed to track the propagation of space weather events from the Sun to Earth.Additionally,it monitors various disturbances generated within the Earth system that impact geospace.Over the past two years,significant progress has been made on the IMCP.In particular,the second phase of construction for the China-Brazil Joint Laboratory for Space Weather has been completed,and the North Pole and Southeast Asia networks are under active construction.The 2024 IMCP joint observation campaign was successfully conducted.To facilitate these developments,the scientific program committee of IMCP was established,following the success of 2023 IMCP workshop and the space weather school,which was co-hosted with the Asia-Pacific Space Cooperation Organization(APSCO)and sponsored by Chinese Academy of Sciences(CAS)and Scientific Committee on Solar-Terrestrial Physics(SCOSTEP).Preparations are now underway for the 2024 workshop in collaboration with the National Institute for Space Research(INPE)in Brazil.展开更多
The particular challenges of modeling control systems for the middle route of the south-to-north water transfer project are illustrated.Open channel dynamics are approximated by well-known Saint-Venant nonlinear parti...The particular challenges of modeling control systems for the middle route of the south-to-north water transfer project are illustrated.Open channel dynamics are approximated by well-known Saint-Venant nonlinear partial differential equations.For better control purpose,the finite difference method is used to discretize the Saint-Venant equations to form the state space model of channel system.To avoid calculation divergence and improve control stability,balanced model reduction together with poles placement procedure is proposed to develop the control scheme.The entire process to obtain this scheme is described in this paper,important application issue is considered as well.Experimental results show the adopted techniques are properly used in the control scheme design,and the system is able to drive the discharge to the demanded set point or maintain it around a reasonable range even if comes across big withdrawals.展开更多
Mu Shiying＇s first short story collection, North Pole, South Pole （Nanbeiji） from 1932, is usually seen as socialist or proletarian literature preceding his later modernist writings. I argue that this view needs to...Mu Shiying＇s first short story collection, North Pole, South Pole （Nanbeiji） from 1932, is usually seen as socialist or proletarian literature preceding his later modernist writings. I argue that this view needs to be revised. In one short story Mu deliberately parodies the social agenda of contemporary leftist writers. The protagonists are neither enlightened workers nor victims of social injustice. On the contrary, they turn to rage, misogyny, and self-righteous violence, and their motives are rooted in their sexual frustrations and inability to cope with modem life. Their righteous ideals are based on fiction and an imagined tradition. Mu＇s construction of the fictive tradition plays an important part in these early short stories, and, in this respect, I compare them with Shi Zhecun＇s writings.展开更多
The anomalous change of two polar sea ice and tropical ocean SST is a very important index for global climate monitoring and prediction. In this paper, wave resonance principle is used to calculate month by month runn...The anomalous change of two polar sea ice and tropical ocean SST is a very important index for global climate monitoring and prediction. In this paper, wave resonance principle is used to calculate month by month running crosscouple correlation coefficient time series between sea ices in different sea areas of the two poles, as well as between themand five elements of El Nino event, to analyze their variation features. and to find out their resonance periods. The reso nance period of two waves is just the strongest interaction period.borne results are as follows: 1. The Arctic sea ice to the Pacific-side (NP11) and Atlantic-side (NP12 ) shows a mu tual strong positive-negative feedback impact with the Antarctic Ross Sea ice (SP12) in equal intensity. 2. Both NP11 andNP12 give a strong positive and negative feedback to the Antarctic Wedded Sea ice (SP13) while it is rather weak in con verse status. It means that the Arctic sea ice plays a leading and controlling role on the Wedded Sea ice. 3. SST of Nino4 area in the central equatorial Pacific has a best resonance period with SP12 in a cycle period of 132 months. It closely re lates to quasi-11-year oscillation period of both. SST of Nino 4 area also has a resonance period with SP13 in a cycle of 61months. There also exist strong interaction periods between the Antarctic sea ice and other elements of El Nino event butweaker than SST of Nino 4 area.展开更多
To study effects of variations in climate-marine environment in the Arctic Ocean on ecology,based on the actual and reestablished data by biomarkers of algae in sediment in 1997,1999,2003,2008,and 2010,the interannual...To study effects of variations in climate-marine environment in the Arctic Ocean on ecology,based on the actual and reestablished data by biomarkers of algae in sediment in 1997,1999,2003,2008,and 2010,the interannual and spatial variations of phytoplankton,zooplankton and chlorophyll a concentration in the Chukchi Sea and the Bering Sea as well as their relations to El Nino-Southern Oscillation( ENSO) and Arctic Oscillation( AO) were analyzed. The results show that there were spatial and temporal anomalies in the phytoplankton community structure reestablished by biomarkers of algae in the Chukchi Sea and the Bering Sea in 1999 and 2010. The total content of biomarkers( brassicasterol,dinosterol,C37 alkenones and chlesterol) in sediment collected in 2010 was far lower than that in 1999,but brassicasterol was dominant in the two years,that is,diatom was dominant,which was consistent with the actual structure and distribution of phytoplankton community in 1999 and 2010; there were great changes in the dominant species of plankton in the two seas in 1999 and 2010,which could be regarded as the ecological response of the North Pole under the background of global warming. Chlorophyll a concentration in the water of the Bering Sea was 0. 720 μg/dm^3 at 0 m and 0. 765μg/dm^3 at 10 m in 1997 and 0. 723 μg/dm^3 at 0 m and 0. 731 μg/dm^3 at 10 m in 2003,and the concentration was very close to each other,which was affected by El Ni1 o and the negative phase of AO. It was 0. 395 μg/dm^3 at 0 m in 1999 and 0. 399 μg/dm^3 at 0 m and 0. 357 μg/dm^3 at 10 m in 2008,which was influenced by La Ni1 a and the positive phase of AO. The phases and intensity of AO and ENSO had various effects on the quantity and dominant species of phytoplankton and zooplankton in the Chukchi Sea and the Bering Sea. During the period of AO with positive or negative phase and El Ni1o( in 1997 and 2003),their combination was favorable to the growth of phytoplankton and zooplankton,while the combination of negative phase of AO and La Nina( in 2010展开更多
基金Supported by International Meridian Circle Program Headquarters,China-Brazil Joint Laboratory for Space Weather(Y42347A99S)。
文摘In 2024,the Chinese Meridian Project(CMP)completed its construction,deploying 282 instruments across 31 stations.This achievement not only provides a robust foundation but also serves as a reference template for the International Meridian Circle Program(IMCP).The IMCP aims to integrate and establish a comprehensive network of ground-based monitoring stations designed to track the propagation of space weather events from the Sun to Earth.Additionally,it monitors various disturbances generated within the Earth system that impact geospace.Over the past two years,significant progress has been made on the IMCP.In particular,the second phase of construction for the China-Brazil Joint Laboratory for Space Weather has been completed,and the North Pole and Southeast Asia networks are under active construction.The 2024 IMCP joint observation campaign was successfully conducted.To facilitate these developments,the scientific program committee of IMCP was established,following the success of 2023 IMCP workshop and the space weather school,which was co-hosted with the Asia-Pacific Space Cooperation Organization(APSCO)and sponsored by Chinese Academy of Sciences(CAS)and Scientific Committee on Solar-Terrestrial Physics(SCOSTEP).Preparations are now underway for the 2024 workshop in collaboration with the National Institute for Space Research(INPE)in Brazil.
基金supported by the National Key Basic Research Program of China ("973" Progject) (Grant No. 2007CB714100)
文摘The particular challenges of modeling control systems for the middle route of the south-to-north water transfer project are illustrated.Open channel dynamics are approximated by well-known Saint-Venant nonlinear partial differential equations.For better control purpose,the finite difference method is used to discretize the Saint-Venant equations to form the state space model of channel system.To avoid calculation divergence and improve control stability,balanced model reduction together with poles placement procedure is proposed to develop the control scheme.The entire process to obtain this scheme is described in this paper,important application issue is considered as well.Experimental results show the adopted techniques are properly used in the control scheme design,and the system is able to drive the discharge to the demanded set point or maintain it around a reasonable range even if comes across big withdrawals.
文摘Mu Shiying＇s first short story collection, North Pole, South Pole （Nanbeiji） from 1932, is usually seen as socialist or proletarian literature preceding his later modernist writings. I argue that this view needs to be revised. In one short story Mu deliberately parodies the social agenda of contemporary leftist writers. The protagonists are neither enlightened workers nor victims of social injustice. On the contrary, they turn to rage, misogyny, and self-righteous violence, and their motives are rooted in their sexual frustrations and inability to cope with modem life. Their righteous ideals are based on fiction and an imagined tradition. Mu＇s construction of the fictive tradition plays an important part in these early short stories, and, in this respect, I compare them with Shi Zhecun＇s writings.
文摘The anomalous change of two polar sea ice and tropical ocean SST is a very important index for global climate monitoring and prediction. In this paper, wave resonance principle is used to calculate month by month running crosscouple correlation coefficient time series between sea ices in different sea areas of the two poles, as well as between themand five elements of El Nino event, to analyze their variation features. and to find out their resonance periods. The reso nance period of two waves is just the strongest interaction period.borne results are as follows: 1. The Arctic sea ice to the Pacific-side (NP11) and Atlantic-side (NP12 ) shows a mu tual strong positive-negative feedback impact with the Antarctic Ross Sea ice (SP12) in equal intensity. 2. Both NP11 andNP12 give a strong positive and negative feedback to the Antarctic Wedded Sea ice (SP13) while it is rather weak in con verse status. It means that the Arctic sea ice plays a leading and controlling role on the Wedded Sea ice. 3. SST of Nino4 area in the central equatorial Pacific has a best resonance period with SP12 in a cycle period of 132 months. It closely re lates to quasi-11-year oscillation period of both. SST of Nino 4 area also has a resonance period with SP13 in a cycle of 61months. There also exist strong interaction periods between the Antarctic sea ice and other elements of El Nino event butweaker than SST of Nino 4 area.
基金Supported by National Natural Science Foundation of China ( 41276199)Chinese Projects for Investigations and Assessments of the Arctic and Antarctic ( CHINARE 2012 - 2016 for 03-04 and 04-03)
文摘To study effects of variations in climate-marine environment in the Arctic Ocean on ecology,based on the actual and reestablished data by biomarkers of algae in sediment in 1997,1999,2003,2008,and 2010,the interannual and spatial variations of phytoplankton,zooplankton and chlorophyll a concentration in the Chukchi Sea and the Bering Sea as well as their relations to El Nino-Southern Oscillation( ENSO) and Arctic Oscillation( AO) were analyzed. The results show that there were spatial and temporal anomalies in the phytoplankton community structure reestablished by biomarkers of algae in the Chukchi Sea and the Bering Sea in 1999 and 2010. The total content of biomarkers( brassicasterol,dinosterol,C37 alkenones and chlesterol) in sediment collected in 2010 was far lower than that in 1999,but brassicasterol was dominant in the two years,that is,diatom was dominant,which was consistent with the actual structure and distribution of phytoplankton community in 1999 and 2010; there were great changes in the dominant species of plankton in the two seas in 1999 and 2010,which could be regarded as the ecological response of the North Pole under the background of global warming. Chlorophyll a concentration in the water of the Bering Sea was 0. 720 μg/dm^3 at 0 m and 0. 765μg/dm^3 at 10 m in 1997 and 0. 723 μg/dm^3 at 0 m and 0. 731 μg/dm^3 at 10 m in 2003,and the concentration was very close to each other,which was affected by El Ni1 o and the negative phase of AO. It was 0. 395 μg/dm^3 at 0 m in 1999 and 0. 399 μg/dm^3 at 0 m and 0. 357 μg/dm^3 at 10 m in 2008,which was influenced by La Ni1 a and the positive phase of AO. The phases and intensity of AO and ENSO had various effects on the quantity and dominant species of phytoplankton and zooplankton in the Chukchi Sea and the Bering Sea. During the period of AO with positive or negative phase and El Ni1o( in 1997 and 2003),their combination was favorable to the growth of phytoplankton and zooplankton,while the combination of negative phase of AO and La Nina( in 2010
