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A numerical study of the South China Sea deep circulation and its relation to the Luzon Strait transport

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Acta Oceanologica Sinica 2002年第2期21卷 187-202页

作者： Yuan Dongliang1. Goddard earth science and technology Center, {3. of Maryland, Baltimore County Code 971, Laboratory for Hydrospheric Processes, NASA/Goddard space Flight Center, Greenbelt, MD 20771, USA Goddard earth science and technology Center University of Maryland Baltimore County Greenbelt MD 20771 United States Code 971 Laboratory for Hydrospheric Processes NASA/Goddard Space Flight Center Greenbelt MD 20771 United States

A fine-resolution MOM code is used to study the South China Sea basin-scale circulationand its relation to the mass transport through the Luzon Strait. The model domain includes the South China Sea, part of the East China Sea, and part of the Philippine Sea so that the currents in the vicinity of the Luzon Strait are free to evolve. In addition, all channels between the South China Sea and the Indonesian seas are closed so that the focus is on the Luzon Strait transport. The model is driven by specified Philippine Sea currents and by surface heat and salt flux conditions. For simplicity, no wind-stress is applied at the *** simulated Luzon Strait transport and the South China Sea circulation feature a sandwich vertical structure from the surface to the bottom. The Philippine Sea water is simulated to enter the South China Sea at the surface and in the deep ocean and is carried to the southern basin by western boundary currents. At the intermediate depth, the net Luzon Strait transport is out of the South China Sea and is fed by a western boundary current flowing to the north at the base of the thermocline. Corresponding to the western boundary currents, the basin circulation of the South China Sea is cyclonic gyres at the surface and in the abyss but an anti-cyclonic gyre at the intermediate depth. The vorticity balance of the gyre circulation is between the vortex stretching and the meridional change of the planetary vorticity. Based on these facts, it is hypothesized that the Luzon Strait transports are determined by the diapycnal mixing inside the entire South China Sea. The South China Sea plays the role of a 'mixing mill' that mixes the surface and deep waters to return them to the Luzon Strait at the intermediate depth. The gyre structures are consistent with the Stommel and Arons theory (1960), which suggests that the mixing-induced circulation inside the South China Sea should be cyclonic gyres at the surface and at the bottom but an anti-cyclonic gy

关键词： The South China Sea deep circulation the Luzon Strait transports

日地空间电磁环境和彗星之间的相互作用的分析和讨论

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空间科学学报 1989年第2期9卷 110-116页

作者：李中元中国科技大学地球和空间科学系

本文根据对彗星资料进行的统计分析,指出彗尾的出现是随机的;并对各种观测到的彗星现象,例如I型彗尾骚动、I型彗尾扭折、以及彗尾边界和磁层顶相遇等现象,与空间电磁环境的关系进行了分析研究,认为不同的现象有比较相似的统计结果,但有... 详细信息

本文根据对彗星资料进行的统计分析,指出彗尾的出现是随机的;并对各种观测到的彗星现象,例如I型彗尾骚动、I型彗尾扭折、以及彗尾边界和磁层顶相遇等现象,与空间电磁环境的关系进行了分析研究,认为不同的现象有比较相似的统计结果,但有不相同的相互作用的机理.

关键词：慧星电磁环境日地空间慧尾

A new method to prepare clean cuticular membrane from fossil leaves with thin and fragile cuticles

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science China earth sciences 2011年第2期54卷 223-227页

作者： WANG Li1,2 & LENG Qin1,3.1 State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of sciences,Nanjing 2.0008,China 2 Graduate School of Chinese Academy of sciences,Beijing 100049,China 3.{3. of science and technology,Bryant university,Smithfield RI 02917,USA 1. State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China2. Graduate School of Chinese Academy of Sciences Beijing 100049 China3. Department of Science and Technology Bryant University Smithfield RI 02917 USA

Leaf cuticle analysis has long been a powerful tool for fossil plant identification, systematics, and palaeoclimatological recon- struction. In recent decades the application of stomatal frequency data that are relied on precise calculation of stomata on plant fossil cuticles to reconstruct ancient atmospheric CO2 concentration made the preparation of cuticular membrane with sufficient size a critical technique in palaeoclimatological research. However, for plants with originally thin and fragile cuticles, e.g., most deciduous plants, conventional techniques sometimes fail to obtain cuticular membranes with sufficient size, or sometimes unable to recover any. This has largely hampered the usage of fossil cuticle analysis in palaeobotanical and palaeo- climatological research. Here, we describe a new method using clear nail polish as a medium to ＂strengthen＂ the originally thin and fragile cuticles prior to maceration procedures. We demonstrate the method by using middle Eocene Metasequoia fossils that were notorious for the difficulty of recovering large-sized clean cuticular membranes due to their thin and fragile nature. Metasequoia, with well-documented and widely-distributed fossil records since the Late Cretaceous and with a living repre- sentative, 114. glyptostroboides, as a comparative reference, bas been widely used as a model genus for the study of evolution of plants, palaeoclimatological reconstruction, and plant adaptation to climate changes. But its deciduous habit produces thin cuticles and makes the preparation of clean cuticular membranes a tedious process. The new method successfully allows us to recover its delicate cuticular membranes with sufficient sizes for SEM observation and stomatal frequency analysis.

关键词： fossil leaf cuticle Metasequoia new method thin and fragile cuticle SEM observation stomatal frequency CO2

Experimental measurement of growth patterns on fossil corals:Secular variation in ancient earth-Sun distances

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Chinese science Bulletin 2010年第35期55卷 4010-4017页

作者： ZHANG WeiJia1,3.4,LI ZhengBin2,3.& LEI Yang1 1 department of Physics,Peking university,Beijing 100871,China 2 department of Electrical Engineering and Computer {3.,Peking university,Beijing 100871,China 3.State Key Laboratory of Advanced Optical Communication Systems & Networks,Peking university,Beijing 100871,China 4 Committee of Yuanpei Honors Program,Peking university,Beijing 100871,China department of Physics Peking University Beijing 100871 China State Key Laboratory of Advanced Optical Communication Systems & Networks Peking University Beijing 100871 China Committee of Yuanpei Honors Program Peking University Beijing 100871 China department of Electrical Engineering and Computer science Peking University Beijing 100871 China

In recent years,much attention has been given to the increase in the earth-Sun distance,with the modern rate reported as 5-15 m/cy on the basis of astronomical ***,traditional methods cannot measure the ancient leaving rates,so a myriad of research attempting to provide explanations were met with unmatched *** this paper we consider that the growth patterns on fossils could reflect the ancient earth-Sun *** mechanical analysis of both the earth-Sun and earth-Moon systems,these patterns confirmed an increase in the earth-Sun *** a large number of well-preserved specimens and new technology available,both the modern and ancient leaving rates could be measured with high precision,and it was found that the earth has been leaving the Sun over the past 0.53.billion *** earth's semi-major axis was 146 million kilometers at the beginning of the Phanerozoic Eon,equating to 97.6% of its current *** modern leaving rates are 5-14 m/cy,whereas the ancient rates were much *** results indicate a special expansion with an average expansion coefficient of 0.57H0 and deceleration in the form of Hubble *** the basis of experimental results,the earth's semi-major axis could be represented by a simple formula that matches fossil measurements.

关键词：地球太阳古代距离生长模式实验石珊瑚量化

A STORABE PROCESS OF THE MAGNETICENERGY RESULTS FROM THE UNSTEADY PLASMA FLOW FIELD IN THE DISTURBANCE REGIONS OF COMETARY TAIL AND ATMOSPHERE

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紫金山天文台台刊 1998年第2期 97-100页

作者： Li Zhong-yuan Shi Zhi-dong Chen Yao(department of earth and space {3., university of Sciece and technology of China, Anhui, hefei, 2.0026 P.R.C (Advanced Centre for Sciece and Astronomy, Third World Academy of {3.s.)

In this paper we discuss coupling processes between a magnetic field and an unsteady plasma motion, and analyze the features of energy storage and conversions in the cometary disturbance regions.

关键词： Comet Disturbance in comet Energy conversions and evolution space plasma pro-cess

The evolution of magnetic helicity in driven reconnection processes and the flux rope structures at the dayside magnetopause

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The evolution of magnetic helicity in driven reconnection pr...

A user-space file system for on-demand legacy desktop software

第十届全国日地空间物理学术讨论会

作者： Cui Hailong Jin Shuping (School of earth and space sciences, {3. of science and technology of China hefei 2.0026)

A two-dimensional MHD simulation with three components is carried out to explore the drivenreconnection processes at the dayside magnetopause. The numerical results show significant enhancementsof the magnetic field strength B and the B component at the centers of the recurrent plasmoid-likestructures. Such features are in line with the signatures of flux transfer events (FTEs) which are envisagedas passages of magnetic flux tubes. The evolution of the topological structure in reconnected flux tubes is

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science China(Information sciences) 2011年第6期54卷 1142-1150页

作者： ZHANG YouHui 1,2 , SU GeLin 1,2 & ZHENG WeiMin 1,2 1 department of Computer science and technology, Tsinghua {3., Beijing 100084, China 2 Tsinghua National Laboratory for Information science and technology, Tsinghua {3., Beijing 100084, China 1. department of Computer science and technology Tsinghua University Beijing 100084 China2. Tsinghua National Laboratory for Information Science and Technology Tsinghua University Beijing 100084 China

Some user-level virtualization technologies have been used to convert legacy software (like the existing Windows desktop applications) into the on-demand software without any modification. To give the client a friendly and compatible method to access on-demand legacy software across the Internet, this paper presents a clientend file system for this usage case. It is a Windows user-space file system based on the cloud storage (where the on-demand software is stored), which converts the local file system accesses into remote visits. Quite a few optimizations are adopted and adjusted to suit the file-access-pattern of on-demand software, including the local cache, metadata/data/software prefetch and content-addressable storage (CAS), to decrease the number of remote visits and/or to overlap IO (input/output) operations with software execution. Detailed access-pattern analyses are also presented. This file system has been implemented and tests show that it is practical for much daily-used software-a local cache of limited size can provide up to 80% hit ratio and the corresponding overhead of running-time is about 3.%. Owing to this method, on any compatible and networked computer, a user can use his/her personalized software conveniently although it does not exist on the local host.

关键词： on-demand software software as a service user-space file system cloud storage

Geochemistry of Trace and Rare earth Elements in Red Soils from the Dongting Lake Area and Its Environmental Significance

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Pedosphere 2009年第5期19卷 615-622页

作者： MAO Long-Jiang MO Duo-Wen YANG Jing-Hong SHI Chen-Xi College of Atmospheric science Nanjing University of Information Science & Technology Nanjing 210044 (China) College of Urban and Environmental sciences Peking University Beijing 100871 (China) department of earth sciences Nanjing University Nanjing 210093 (China)

Trace element(TE) and rare earth element(REE) contents in red soils from the Dongting Lake area of China were determined to understanding the provenance and weathering characteristics of the red *** results showed similar REE distribution patterns among red soils from the Dongting Lake area,Xiashu loess from Zhenjiang,loess and Pliocene red soil from the Loess *** patterns implied a similar provenance from dust-storms,except for red soil R5 which formed by bedrock weathering and had significant light REE(LREE) enrichment and heavy REE(HREE) depletion due to longer weathering periods and higher intensity of *** element,especially the Rb/Sr and Li/Ba ratios,and REE,especially the LREE/HREE ratio and δEu could trace weathering *** Rb/Sr,Li/Ba,and LREE/HREE ratios and negative Eu anomalies were present in the red soils from the Dongting Lake *** weathering intensity was in the decreasing order of R5 in the Dongting Lake area > red soils from the Dongting Lake area(including reticulate red soil,weak reticulate red soil,and homogeneous red soil formed by dust storms) > Xiashu loess from Zhenjiang > loess-paleosol and Pliocene red soil from the Loess *** in the TE and REE contents of soil could be effectively used to study the provenance and the weathering intensity.

关键词： Hunan Province provenance sedimentary processes weathering intensity

Optimal MAC based cooperative spectrum sensing in cognitive radio networks

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science China(Information sciences) 2012年第6期55卷 1388-1396页

作者： CHEN Zhong 1,ZHANG XianDa 1 & YANG LanJuan 2 1 State Key Laboratory of Intelligent technology and Systems,Tsinghua National Laboratory for Information science and technology,{3. of Automation,Tsinghua university,Beijing 100084,China 2 Institute of Command Automation,PLA university of science and technology,Nanjing 2.0007,China 1. State Key Laboratory of Intelligent technology and Systems Tsinghua National Laboratory for Information Science and Technology Department of Automation Tsinghua University Beijing 100084 China2. Institute of Command Automation PLA University of Science and Technology Nanjing 210007 China

This paper considers a cognitive radio (CR) system in non-ideal fading wireless channels and pro-poses cooperative spectrum sensing schemes based on coherent multiple access channels (MAC),serving as an alternative way to improve the cooperative spectrum sensing performance and provide space diversity for spec-trum *** statistics are transmitted using a common channel from the secondary users (SUs) to a fusion center (FC) where the global decision is *** optimal scaling factors of the proposed schemes are obtained by maximizing the detection probability under a target false alarm probability and a transmit power *** the proposed optimal MAC scheme has high computational complexity,a sub-optimal solu-tion based on maximization of the deflection coefficient (DC) is also *** results show that the proposed algorithms can significantly improve the spectrum sensing performance and approach the detection baseline.

关键词： cognitive radio (CR) spectrum sensing multiple access channel (MAC) deflection coefficient optimization