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The establishment of crystal position look-up table for positron emission tomography with block detectors

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Science china(Technological sciences) 2009年第8期52卷 2418-2423页

作者： CHAI Pei1,2 & SHAN BaoCi1 1 Key Laboratory of Nuclear Analytical Techniques, Institute of High Energy Physics, chinese Academy of sciences, beijing 100049, {3. 2 graduate university of chinese Academy of sciences, beijing 100049, {3. Key Laboratory of Nuclear Analytical Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing China graduate university of chinese Academy of {3. Beijing China

A method has been developed to establish the crystal position look-up table for positron emission tomography with block detectors. It is based on the principle that the counts in crystal position histogram obey the Gaussian mixture model (GMM). This method has taken full consideration of the characteristics of the GMM and the detector itself. The experimental results have proved that it is simple, reliable, and universal.

关键词： positron emission tomography position look-up table 2-D position histogram

Regional soil moisture simulation for Shaanxi Province using SWAT model validation and trend analysis

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Science china Earth sciences 2010年第4期53卷 575-590页

作者： LI MingXing1,2,MA ZhuGuo1 & DU JiWen3.1 Key Laboratory of Regional Climate-Environment Research for Temperate East Asia,Institute of Atmospheric Physics,chinese Academy of sciences,beijing 100029,{3. 2 graduate university of chinese Academy of sciences,beijing 100049,{3. 3.Shaanxi Administration of Meteorology,Xi’an 710014,{3. Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China graduate university of chinese Academy of {3. Beijing China Shaanxi Administration of Meteorology Xi’an China

The soil moisture in Shaanxi Province,a region with complex topography,is simulated using the distributed hydrological model Soil Water Assessment Tool(SWAT).Comparison and contrast of modeled and observed soil moisture show that the SWAT model can reasonably simulate the long-term trend in soil moisture and the spatiotemporal variability of soil moisture in the *** to NCEP/NCAR and ERA40 reanalysis of soil moisture show that the trend of variability in soil moisture simulated by SWAT is more consistent with the *** model results suggested that high soil moisture in surface soil layers appears in the southern Shaanxi with high vegetation cover,and the Qinling mountainous region with frequent orographic *** deeper soil layers,high soil moisture appears in the river basins and *** regional soil moisture showed a generally decreasing trend on all soil layers from 1951 to 2004,with a stronger and significant decreasing trend in deeper soil layers,especially in the northern parts of the province.

关键词： SWAT soil moisture content simulation validation trend analysis

Sea level variations in the South china Sea inferred from satellite gravity,altimetry,and oceanographic data

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Science china Earth sciences 2012年第10期55卷 1696-1701页

作者： FENG Wei 1,2,ZHONG Min 1,3.& XU HouZe 1,3.1 State Key Laboratory of Geodesy and Earth’s Dynamics,Institute of Geodesy and Geophysics,chinese Academy of sciences,Wuhan 43.077,china 2 {3. university of chinese Academy of sciences,beijing 100049,china 3.Institute of Geophysics,Huazhong university of Science and Technology,Wuhan 43.074,china State Key Laboratory of Geodesy and Earth’s Dynamics Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China graduate university of chinese Academy of {3. Beijing China Institute of Geophysics Huazhong University of Science and Technology Wuhan China

Sea level variations(SLVs) can be divided into two major components:the steric SLV and the mass-induced *** two components of SLV in the South china Sea(SCS) are studied by using satellite altimetry,GRACE(Gravity Recovery and Climate Experiment) satellite gravity,and oceanographic data on annual and inter-annual *** the annual timescale,the geographic distribution of mass-induced SLV's amplitude jointly estimated from altimetry and the ECCO(Estimation of the Circulation and Climate of the Ocean) model agrees very well with that from *** observes obvious seasonal mass-induced SLV in the SCS with annual amplitude of 2.7±0.4 cm,which is consistent with the annual amplitude of 2.7±0.3.cm estimated from the steric-corrected *** the inter-annual timescales,the mean SLV in the SCS shows a large oscillation,which is mainly caused by the steric *** trend of mean SLV inferred from altimetry in the SCS is 5.5±0.7 mm/yr for the period of 1993.2009,which is significantly higher than the global sea level rise rate of 3.3.0.4 mm/yr in the same *** is no obvious trend signal in the mass-induced SLV detected from GRACE that indicates the water exchange between the SCS and its adjacent seas and land is in balance within the study period.

关键词： altimetry GRACE ECCO the South china Sea sea level variation

The solid lubricating material experiment device for Shenzhou-7 Spaceship

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Science china(Technological sciences) 2010年第9期53卷 2521-2527页

作者： WANG Ke1,2,REN WeiJia1,WANG ShiDa1 & WENG LiJun3.1 Academy of Opto-Electronics,chinese Academy of sciences,beijing 100190,{3. 2 graduate university of chinese Academy of sciences,beijing 100049,{3. 3.Lanzhou Institute of Chemical Physics,chinese Academy of sciences,Lanzhou 73.000,{3. Academy of Opto-Electronics Chinese Academy of Sciences Beijing China graduate university of chinese Academy of {3. Beijing China Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou China

A solid lubricating material exposure experiment in space is one of the missions during the seventh manned spaceflight of china,and the key is to develop a device which can be fixed reliably outside of the orbital module and can be fetched conveniently by an astronaut during space *** solid lubricating material experiment device needs to be locked reliably in a vibrating and impacting environment during the launch phase,and should meet the requirement that it can be unlocked and fetched reliably by the astronaut wearing an extravehicular spacesuit via simple operations in orbit in an environment of high and low *** for the device we developed,the environmental characteristic of the mission was analyzed,the mechanical analysis and thermal analysis were carried out,and then a mechanism with functions of mechanical locking,structural self-locking and manual unlocking was *** device was verified by a sequence of experiments and was fetched by the astronaut during the flight of the Shenzhou-7 Spaceship.

关键词： manned spaceflight exposure experiment mechanism unlock

Eclogites in the interior of the Tibetan Plateau and their geodynamic implications

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chinese Science Bulletin 2009年第15期54卷 2556-2567页

作者： ZHANG KaiJun1,2 & TANG XianChun2,3.1 Department of Earth sciences, Nanjing university, Nanjing 210093. china 2 Guangzhou Institute of Geochemistry, {3. Academy of sciences, Guangzhou 510640, china 3.graduate university of {3. Academy of sciences, beijing 100049, china Department of Earth sciences Nanjing University Nanjing China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China graduate university of chinese Academy of {3. Beijing China

Eclogites have been recently reported in the interior of the Tibetan Plateau, including in the central Qiangtang metamorphic belt, in the Basu metamorphic massif of the eastern Bangong-Nujiang suture zone, and at Songdo and Pengco in the eastern Lhasa terrane. Some typical ultrahigh-pressure (UHP) metamorphic phenomena, e.g., garnet exsolution from clinopyroxene, were documented in the Basu and Pengco eclogites. The UHP metamorphism in the interior of the Tibetan Plateau marked by these eclogites generally took place in the Early Mesozoic. Along with exhumation of these eclogites, (post-) collision-related magmatism extensively occurred around the central Qiangtang belt, the eastern Ban-gong-Nujiang suture zone, and the eastern Lhasa terrane. The occurrence of these Early Mesozoic ec-logites manifests an out-of-sequence evolution of the Tethys, and they could be a product of diachro-nous collision between the eastern Qiangtang terrane and the irregular continental margin of the united western Qiangtang-Lhasa plate, along the linked eastern Bangong-Nujiang-central Qiangtang zone. The collision-related magmatic rocks could have been originated from lithospheric thickening, melting, or detachment due to the collision. The presence of UHP metamorphic rocks in central Qiangtang and Basu implies likely continental deep-subduction, and the denudation of these two metamorphic zones could have served as the source of the Triassic turbidites in the Songpan-Garzê complex and the Ju-rassic turbidites in the western Bangong-Nujiang zone, respectively. However, studies of the eclogites in the interior of the Tibetan Plateau just began, and many principal aspects still remain to be explored, such as their distributions, typical lithologies and minerals, temperature-pressure conditions, timing of formation and exhumation, protoliths and tectonic setting, and relationship with the evolution of the Tethys and large-scale basins in Tibet.

关键词：地球动力学意义青藏高原榴辉岩

Inertial theory of the mean Hadley circulation under the condition of nonstatic equilibrium

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Science china Earth sciences 2006年第5期49卷 546-553页

作者： CHAO Jiping1 & LIU Fei2,3.1. National Marine Environmental Forecasting Center, beijing 100081, china 2. Key Laboratory Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, chinese Academy of {3., beijing 100029, china 3. graduate university of chinese Academy of {3., beijing 100049, china National Marine Environmental Forecasting Center Beijing China Key Laboratory Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China graduate university of chinese Academy of {3. Beijing China

Tropical atmosphere is divided into two layers, the layer near the ground is the planet boundary layer, where the motion is linear, if the radiation equilibrium temperature is given at the top of the boundary layer, the vertical motion there can be obtained. It is the non-viscous ideal atmos- pheric layer above the boundary one, where the motion is nonlinear. After getting the conservation laws of angular momentum, potential temperature and potential vortex, the inertial theory of the Hadley circulation driven by the vertical motion of the boundary layer is established, followed by sev- eral examples of its application.

关键词： Hadley circulation, inertial theory, conservation laws of angular momentum, potential temperature and potential vortex.

Analysis and application of automatic deformation monitoring data for buildings and structures of mining area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 516-522页

作者： XIAO Jie1, 2, 3. ZHANG Jin4 1. Institute of Geodesy and Geophysics, chinese Academy of sciences, Wuhan 43.077, china 2. Key Laboratory of Dynamic Geodesy, Institute of Geodesy and Geophysics, chinese Academy of sciences, Wuhan 43.077, china 3. graduate School of chinese Academy of sciences, beijing 100049, china 4. Department of Surveying and Mapping, Taiyuan university of Technology, Taiyuan 03.024, china Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China Key Laboratory of Dynamic Geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China graduate School of chinese Academy of sciences Beijing 100049 China Department of Surveying and Mapping Taiyuan University of Technology Taiyuan 030024 China

The buildings and structures of mines were monitored automatically using modern surveying technology. Through the analysis of the monitoring data, the deformation characteristics were found out from three aspects containing points, lines and regions, which play an important role in understanding the stable state of buildings and structures. The stability and deformation of monitoring points were analysed, and time-series data of monitoring points were denoised with wavelet analysis and Kalman filtering, and exponent function and periodic function were used to get the ideal deformation trend model of monitoring points. Through calculating the monitoring data obtained, analyzing the deformation trend, and cognizing the deformation regularity, it can better service mine safety production and decision-making.

关键词： wavelet analysis Kalman filtering deformation monitoring data analysis mine

Effects of various solar indices on accuracy of Earth’s thermospheric neutral density models

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Science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 1120-1128页

作者： WANG HongBo1,2 & ZHAO ChangYin1 1 Purple Mountain Observatory, chinese Academy of sciences, Nanjing 210008, china 2 {3. university of chinese Academy of sciences, beijing 100049, china Purple Mountain Observatory Chinese Academy of Sciences Nanjing China graduate university of chinese Academy of {3. Beijing China

Four kinds of solar indices F10.7, E10.7, S10, Mg10 and four thermospheric neutral density models, i.e., CIRA72, DTM94, NRLMSISE00 and JB2006, are discussed. The CHAMP accelerometer data are used to calculate thermospheric total mass density. Based on the comparison of the model densities with CHAMP observations, the effects of various indices on the model accuracy are detected. It is found that under quiet and moderate solar conditions (F10.7200) the error’s standard deviation using E10.7 increases quickly and causes the models’ accuracy to fall down. With regard to S10, Mg10, their effects under quiet solar conditions are inconspicuous. If under active solar conditions, they can reduce the model error’s standard deviation by 5%-10%, implying that S10, Mg10 make the model error more stable. The JB2006 model, which was constructed by multi-solar-index (F10.7, S10, Mg10), is compared with DTM94 and NRLMSISE00 based on single-solar-index. It is found that JB2006’s accuracy is better than DTM94’s, and is close to NRLMSISE00 under the quiet solar condition. During the solar burst occurring on October 26, 2003. JB2006 has been in best agreement with CHAMP observations. All in all, the new indices may improve thermospheric density models’ accuracy under some special conditions. Concretely, E10.7 may reduce the average error of models and S10, Mg10 may prevent the error’s divergence.

关键词： solar radiation index CHAMP accelerometer data neutrals density model

Hedychium menghaiense (Zingiberaceae),a new species from Yunnan,china

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Journal of Systematics and Evolution 2010年第2期48卷 146-151页

作者： 1,2,3.iu HU 1Nian LIU 1(Zhongkai university of Agriculture and Engineering,Guangzhou 510225,china) 2(South china Botanical Garden,{3. Academy of sciences,Guangzhou 510650,china) 3.graduate School of {3. Academy of sciences,beijing 100049,china) (Zhongkai university of Agriculture and Engineering Guangzhou 510225 China) (South china Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China) (graduate School of chinese Academy of sciences Beijing 100049 China)

Hedychium menghaiense *** & ***,a new species of the Zingiberaceae from Yunnan Province,china,is described and *** new species is currently known only from its type locality,Nannuoshan Mountain,Menghai County,growing under evergreen broad-leaved forests at altitudes of 1400-1700 *** is similar to Hedychium forrestii Diels,but differs in its narrower and emarginate labellum folded inwards lengthwise,narrower staminodes,and scarlet *** recognition of the new species is supported by the results from analysis of sequence-related amplified polymorphism markers.

关键词： Hedychium Hedychium menghaiense X.Hu & N.Liu new species SRAP markers Zingiberaceae