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Timeliness evaluation of task-oriented networked space-based information system

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Journal of Systems Engineering and Electronics 2011年第4期22卷 621-627页

作者： Chen Chen 1,2,and Jie Chen 2,3.1.Department of Automation,Tsinghua University,beijing 100084,P.R.China 2.School of Automation,beijing Institute of Technology,beijing {3.,P.R.China 3.Complex System Intelligent Control and Decision,Ministry of Education,beijing {3.,P.R.China Department of Automation Tsinghua University Beijing 100084 P. R. China School of Automation Beijing Institute of Technology Beijing 100081 P. R. China School of Automation Beijing Institute of Technology Beijing 100081 P. R. China Complex System Intelligent Control and Decision Ministry of Education Beijing 100081 P. R. China

Task-oriented networked information system is an integrated information system which builds on multi-satellite networking to accomplish one or more tasks. In the background of emer- gency relief for applications, system working flow and response process are analyzed, and a timeliness effectiveness evaluation index system is constructed at multi-task level. The effectiveness is a measurement of promptness of information return. In evalua- tion process, system performance and tasks are associated, then an evaluation model based on efficacy function is established, and different evaluation criteria are selected for different tasks. A distributed simulation system is constructed, and the execution of task is decomposed. The simulation platform provides a comprehensive data source for evaluation. The results are easy to compare with each other, which reflects system time efficiency in different satellites networks and provides actual systems with basis and reference for design and application.

关键词： timeliness efficacy function space-based informationsystem simulation system.

Cloud Climatology Characteristics of China from ISCCP Data

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Cloud Climatology Characteristics of China from ISCCP Data

The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

第三届中日韩气象学术会议

作者： Liu Ruixia (national satellite Meteorological center) Liu Yujie (national satellite Meteorological center beijing 100081) Du Bingyu (Nanjing Institute of Meteorology Nanjing 210044)

＜正＞Based on the cloud amount of ISCCP D2,the spatial distribution characters and the temporal variation of cloud amount over 3.regions of China are analyzed using System cluster analysis *** we analyzed the variation trend of cloud over china and concluded that in north east of China the cloud amount increased and decreased in the west of China and in the north of *** SVD modes based on two fields between winter total cloud amount over Tibetan Plateau and summer precipitation in China are computed and credibility of teleconnection analyzed by *** result show that winter total cloud amount over Tibetan Plateau and the summer precipitation in part of north and north-east China.

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Science China Earth Sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2, CAI Qiangguo1, YUE Zhongqi3. LU Zhongchen4, LIANG Guanglin1& HUANG Jianguo5.1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Re-search, Chinese Academy of Sciences, beijing 100101, China 2. Institute of Forestry, Chinese Academy of Forestry Sciences, beijing 100091, China 3. Department of Civil Engineering, University of Hong Kong, Hong Kong, China 4. Eco-environmental Research {3., Chinese Academy of Sciences, beijing 100085. China 5. College of Resources and Environment, Southwest Agricultural University, Chongqing 400716, China Correspondence should be addressed to Chen Hao Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Institute of Forestry Chinese Academy of Forestry Sciences Beijing China Department of Civil Engineering University of Hong Kong Hong Kong China Eco-environmental Research center Chinese Academy of Sciences Beijing China College of Resources and Environment Southwest Agricultural University Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 5.0 mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D5. (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4% less than the role of the intermediate diameter (D5., mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2, it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 3.%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

Biomass estimation and uncertainty analysis based on CBERS-02 CCD camera data and field measurement

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Science China(Technological Sciences) 2005年第S2期48卷 116-128页

作者： CHEN Liangfu1,2, GAO Yanhua1,3. CHENG Yu1,3. WEI Zheng1,3. XIAO Qing1,4, LIU Qinhuo1, YU Tao1, LIU Qijing5. GU Xingfa1 & TIAN Guoliang1 1. State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing Applications, Chinese Academy of Sciences, beijing 100101, China 2. Geography and Environment College, Jiangxi Normal University, Nanchang 3.0027, China 3. Graduate University of Chinese Academy of Sciences, beijing 10003., China 4. beijing Research Institute of Uranium Geology, beijing 100875. China 5. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 100101, China State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China

The study site is located in Qianyanzhou experimental station and the surrounding area. Based on CBERS-02 satellite data and field measurement, we not only discussed the relationship between NDVI and biomass of two species of coniferous plantations, namely, Pinus massoniana Lamb and Pinus elliottii Engelm, but also introduced the biomass models based on NDVI. The comparison between measured biomass in Qianyanzhou and biomass derived from CBERS-02 CCD data showed that it is feasible to estimate biomass based on NDVI. But its limitations cannot be ignored. This kind of model depends on the dominant vegetation species. There are some effect factors in estimating biomass based on NDVI. This paper analyzes these factors based on fine-resolution CBERS-02 CCD data and some conclusions are drawn: In Qianyanzhou, the area with good vegetation coverage, the nonlinearity of NDVI has little influence on scaling-up of NDVI. As a result of surface heterogeneity, scaling-up can cause NDVI within each pixel to change. Because scaling-up can cause pixel attribute to change, the applicability of biomass model is one of the sources of error in estimating biomass.

关键词： NDVI biomass scaling effect scaling-up.

Protein Product Encoded by a Human Novel Gene E973. Enhances AP-1 Activity through Interacting with Jab1

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Acta Biochimica et Biophysica Sinica 2004年第1期36卷 11-15页

作者： Zhao-Qing WANG, Han-Dong WEI, and Fu-Chu HE(Department of System Biology, beijing Institute of Radiation Medicine, Chinese Human national center at beijing, beijing 10085., China) Department of System Biology Beijing Institute of Radiation Medicine Chinese Human National Center at Beijing Beijing 100850 China

A novel human gene, named E973. (a clone number of fetal liver cDNA library), has been identified from more than 14,000 expressed sequence tags (ESTs) based on our large scale sequencing of human fetal liver cDNA libraries. Although sequencing of this novel human gene indicates that it is a leucine zipper protein, the function of E973. and its homologous genes among species is unknown yet. To find out physiological functional clue of E973., the yeast two-hybrid system was used to screen the E973.-interac-ting protein(s), and one clone containing a cDNA insert with almost the entire coding sequence (amino acids 3.-3.5. of human Jabl (Jun-activating domain binding protein 1) that interacted specifically with E973. was identified. A specific association between Jabl and E973. was shown by co-immunoprecipitation and co-localization experiments. Furthermore, E973. appeared to enhance Jab 1 -induced AP-1 activity in a concentration-dependent manner and Jabl may be involved in the intracellular signaling trans

关键词： human E973. gene CSN5.Jabl protein-protein interaction signaling transduction

Numerical simulation of topography effects on the “00.7” severe rainfall in beijing

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Progress in Natural Science:Materials International 2005年第9期15卷 818-826页

作者： ZHANG Chaolin1**, JI Chongping1, KUO Yinghwa2, FAN Shuiyong1, XUAN Chunyi3.and CHEN Min1(1. Institute of Urban Meteorology, China Meteorological Administration, beijing 100089, China 2. Mesoscale and Microscale Meteorology Division, national center for Atmospheric Research, Boulder, CO 803.7-3.00, USA 3. beijing Meteorological Bureau, beijing 100089, China) Institute of Urban Meteorology China Meteorological Administration Beijing 100089 China. Mesoscale and Microscale Meteorology Division National Center for Atmospheric Research Boulder CO 80307-3000 USA. beijing Meteorological Bureau Beijing 100089 China

In an effort to study the severe rainfall event of 4—5.h July 2000 in beijing (with 24h accumulated precipitation of 240 mm), we perform numerical simulations to investigate this event using the MM5.3.6 model. The model is initialized with the MM5.WRF 3.VAR analysis, which incorporates the ground-based GPS precipitable water vapor, automatic and conventional meteorological observations in its assimilation step. For 24 h accumulated precipitation forecast, the threat scores are 0.72, 0.76, 0.67 and 0.63. for thresholds of 1, 5. 10, and 20 mm, respectively. Holding other factors unchanged, sensitivity experiments were conducted with different topographic resolutions of 110, 5. and 3.7 km to investigate the topographic effects on precipitation over the beijing area. In these sensitivity experiments, we attempt to preserve the realistic orographic distribution in the model topography under the condition of keeping the dynamic-thermodynamic consistency of the initial model atmosphere to the extent possible. Results indicate that the unique topographic distribution and variations in the beijing area play an important role in determining the location, distribution and intensity of heavy precipitation.

关键词： topography heavy rainfall 3.VAR ground-based GPS numerical simulation.

A one-dimensional heat transfer model of the Antarctic Ice Sheet and modeling of snow temperatures at Dome A, the summit of Antarctic Plateau

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Science China Earth Sciences 2010年第5期53卷 763-772页

A vertical one-dimensional numerical model for heat transferring within the near-surface snow layer of the Antarctic Ice Sheet was developed based on simplified parameterizations of associated physical processes for the atmosphere, radiation, and snow/ice systems. Using the meteorological data of an automatic weather station (AWS) at Dome A (80°22′S, 70°22′E), we applied the model to simulate the seasonal temperature variation within a depth of 20 m. Comparison of modeled results with observed snow temperatures at 4 measurement depths (0.1, 1, 3. 10 m) shows good agreement and consistent seasonal variations. The model results reveal the vertical temperature structure within the near-surface snow layer and its seasonal variance with more details than those by limited measurements. Analyses on the model outputs of the surface energy fluxes show that: 1) the surface energy balance at Dome A is characterized by the compensation between negative net radiation and the positive sensible fluxes, and 2) the sensible heat is on average transported from the atmosphere to the snow, and has an evident increase in spring. The results are considered well representative for the highest interior Antarctic Plateau.

关键词： Antarctic Ice Sheet near-surface layer energy transfer numerical model

The primary results of quantitative ocean color retrieval in China coastal area with CBERS CCD data

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Science China(Technological Sciences) 2005年第S2期48卷 161-176页

作者： TANG Junwu1,2, MA Chaofei1, NIU Shengli1, WANG Xiaomei1, SONG Qingjun1 & DING Jing1 1. national satellite Ocean Application Service, beijing 100081, China 2. State Key Laboratory of Remote Sensing Science, {3. 100010, China national satellite Ocean Application Service Beijing 100081 China

Using the techniques of quantitative ocean color sensing, the in-water ocean color algorithms for sediment and chlorophyll-a retrieval are established for CBERS-02 CCD broad spectral bands based on in situ data. The remote sensing reflectance of water is derived from CCD radiance data by a clear water atmospheric correction algorithm. Then, the sediment and chlorophyll-a concentrations are retrieved from CCD image. The sediment retrieval is quite satisfactory, but the chlorophyll-a retrieval is not so good because of the broadband width and low signal-to-noise ratio of the CCD camera.

关键词： CBERS-02 CCD ocean color sensing atmospheric correction retrieval of water constituents.

Ni/_n-SiO_2 Composite Coating Prepared by Brush Plating with Pulse Current

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稀有金属材料与工程 2012年第S1期41卷 414-417页

作者： Tan Jun1,Wu Di2,Yao Qiong3.Fan Wenchao1 1 national Key Laboratory for Remanufacturing,Academy of Armored Forces Engineering,beijing 100072,China 2 Key Laboratory of Surface Engineering,Academy of Armored Forces Engineering,beijing 100072,China 3.Xichang {3. Launching center,Xichang 615.00,China Acad Armored Forces Engn Natl Key Lab Remfg Beijing 100072 Peoples R China Acad Armored Forces Engn Key Lab Surface Engn Beijing 100072 Peoples R China Xichang satellite Launching Ctr Xichang 615000 Peoples R China

Nickel and silicon dioxide nanoparticle composite coatings were prepared by brush plating with direct and pulse *** surface morphology,microstructure,hardness and wear resistance of the coatings were investigated by scanning electron microscope(SEM),transmission electron microscope(TEM),mirohardness tester and ball-on-disk *** results show that the technical parameters,pulse current,duty circle and frequency,are of great influence on the growth of crystalline and properties of the *** with the coating plated with direct current,the coatings plated with pulse currents have smaller nanocrystalline,contain more SiO2 nanoparticle and have higher hardness and wear resistance.

关键词： nano composite coating electrodeposition pulse current brush plating