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Observability Conditions of Switched Linear Singular Systems

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Observability Conditions of Switched Linear Singular Systems

第2.届中国控制会议

作者： Meng Bin beijing institute of Control Engineering, China {2. of Space Technology, beijing 100080 {2. of Mathematics and Systems Science, chinese academy of sciences, beijing 100080

＜正＞The observability problem of switched linear singular systems （SLS） is studied in this paper. Based on the observability definition, the unobservable subspaces of given switching laws are investigated under the condition that all subsystems are regular. A necessary condition and a sufficient condition for observability of SLS systems are given. It is shown that the observability and controllability are dual for some special SLS systems with circulatory switching laws. The method developed here is applicable to the observability analysis of normal switched linear systems.

关键词： Switched system! Singular system Observability Unobservable subspace

Reconstructing temperature change in Central East China during 601-92. AD

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Science Bulletin 2010年第34期 3946-3956页

作者： GE QuanSheng,LIU HaoLong,ZHENG JingYun & ZHANG XueZhen institute of Geographic sciences and Natural Resources Research,{2.,beijing 100101,China

Using historical records on first and last frost and snow,spring cultivation,David peach blossom,autumn crop harvest,grade of sea freeze and change in northern citrus boundary,we reconstructed temperature change during 601-92. *** mean temperature of the winter half-year(October to April)over Central East China during this period was about-0.2.°C higher than that of the present(1961-2.00 AD mean).During 601-82. AD,mean temperature was about-0.52.C higher than the *** 82.-92. AD,the mean temperature was 0.42.C lower than the *** temperature fluctuations were characterized by a maximum amplitude of 1.05°C at the centennial scale,1.38°C at the 50-year scale,2.02.C at the 30-year scale,and 2.3°C at the 2.-year *** were four peaks warmer than today(601-62. AD,mean of 1°C higher temperature;641-660 AD,1.44°C;701-72. AD,0.88°C;781-800 AD,0.65°C).Three cold periods were in 741-760,82.-840,and 881-900 AD,the mean temperature of which was 0.37-0.87°C lower than the present.

关键词： Sui and Tang Dynasties Central East China phenological record human impression record reconstruction of tempera-ture change

Antioxidation Mechanism of Haematococcus Pluvialis Cells Exposed to Superoxide Free Radicals

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Antioxidation Mechanism of Haematococcus Pluvialis Cells Exp...

中国海洋湖沼学会藻类学分会第七届会员大会暨第十四次学术讨论会

作者： ZHANG Xiaoli~(1,2. LIU Jianguo~(1,**) SUN Yanhong~(1,2. LIN Wei~1 1 Research and Development Center of Marine Biotechnology,institute of Oceanology,chinese academy of sciences,Qingdao 2.6071,P.R.China 2.Graduate University of chinese academy of sciences,beijing 100039,ER.China

Three types of Haematococcus pluvialis cells were exposed to high concentration of superoxide anion radical(O2..Their antioxidation capacities and responsive sequences were studied by analyzing malondialdehyde content and the activities of superoxide dismutases,peroxidase,catalase and ascorbate *** results showed that defensive enzymes and astaxanthin co-existed to protect the organism against oxidative stress but they varied significantly in each type of *** green cells,the antioxidative enzymes played a key role and had higher activities than that in red cells. Of the four defensive enzymes tested in green cells,superoxide dismutases was the first to eliminate O,followed by peroxidase to eliminate HO,thereafter ascorbate peroxidase and catalase initiated their own protective *** the contrary,astaxanthin was the main antioxidation mechanism and scavenged reactive oxygen species firstly in red cells. It was concluded that astaxanthin reacted with reactive oxygen species much faster and had a stronger capacity to protect lipid peroxidation than that of protective enzymes.

关键词： astaxanthin Haematococcus pluvialis lipid peroxidation reactive oxygen species

Invasive effects of Ageratina adenophora Sprengelon soil microbial community and soil enzyme and physical and chemical properties

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Invasive effects of Ageratina adenophora Sprengelon soil mic...

第二届全国生物入侵学术研讨会

作者： LI Hui-Na~(1,2.,LIU Wan-Xue~2.WAN Fang-Hao~(2.),CAO Yuan-Yin~1 (1 College of Plant Protection of Shenyang Agriculture University,Shenyang 110161 2.institute of Plant Protection,chinese {2. of Agricultural sciences,beijing 100081)

To explore the effects of Ageratina adenophora Sprengel(Asteraceae) on soil ecology,soil microbial communities were analyzed using PCR-DGGE,the activities of 3 enzymes and 8 soil physical and chemical factors were measured following A adenophora *** to non-invaded site and native plant site,invasion of *** modified soil microbial community *** was most noticeable that *** increased soil organic carbon,NO3-N, NH4-N,available P,available K content and the activities of urase,neutral phosphatase,alkaline phosphatase and *** quantity of soil fungi,azotobacteria,ammonia oxidizing bacteria were most abundant in heavily invaded *** azotobacteria,ammonia oxidizing bacteria and urase, phosphatase were significantly associated with most of the measured soil physical and chemical *** examined bacterial community composition in soil following Ageratina adenophora invasion in China using PCR-DGGE method which can detect variation of microbial gene diversity in *** results of DGGE bands showed that *** had changed the soil bacterial communities,especially the soil nutrition cycling and soil enzyme related soil microbe groups, probably creating favorable soil environment to benefit *** invasion-induced changes of soil microbial community and physical and chemical properties may be used by *** to expand rapidly in invasive ranges.

关键词： Ageratina adenophora exotic plant activity of soil enzyme soil physical and chemical properties soil microbial community

Early diagenesis of nurtrients (C, N, P and Si) stored in sediments of two reservoirs in southwestern China

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Acta Geochimica 2006年第S1期 161-162页

作者： Yuchun WANG1, Jun ZHU2. Congqiang LIU2.1 Dept. of Water Environment, China institute of Water Resources and Hydropower Research, beijing 100044, China 2.State Key Laboratory of Environmental Geo{2., institute of Geo{2., chinese academy of sciences, Guiyang 550002. China

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注意分配与注意选择能力的年龄差异比较

心理科学 2004年第6期27卷 1307-1309页

作者：罗婷焦书兰中国科学院心理研究所北京100101

为了考察注意能力的年龄差异 ,分别从注意分配能力和注意选择能力两个方面对青年和老年被试的表现进行了比较。结果表明 :青、老年在注意分配能力上没有显著的差异 ;而青、老年在注意选择能力上却有显著的差异 ,老年的注意选择能力有显... 详细信息

为了考察注意能力的年龄差异 ,分别从注意分配能力和注意选择能力两个方面对青年和老年被试的表现进行了比较。结果表明 :青、老年在注意分配能力上没有显著的差异 ;而青、老年在注意选择能力上却有显著的差异 ,老年的注意选择能力有显著的衰退。因此。

关键词：注意分配注意选择能力年龄差异比较研究认知年老化认知能力注意资源

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石油污染土壤植物-微生物修复研究进展

生态学杂志 2006年第1期25卷 93-100页

作者：蔺昕李培军台培东巩宗强张海荣中国科学院沈阳应用生态研究所

依据国内外近10年来有关石油污染土壤生物修复研究的成果,综合阐述了石油污染土壤的植物修复、微生物修复及植物-微生物联合修复方法研究,重点讨论植物-微生物联合作用,主要包括植物根际微生物、根分泌物以及菌根对石油污染物降解的影响... 详细信息

依据国内外近10年来有关石油污染土壤生物修复研究的成果,综合阐述了石油污染土壤的植物修复、微生物修复及植物-微生物联合修复方法研究,重点讨论植物-微生物联合作用,主要包括植物根际微生物、根分泌物以及菌根对石油污染物降解的影响,提出了污染土壤原位修复中需要重视的问题。

关键词：污染土壤石油微生物修复植物修复

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Mechanical Design and Preliminary Realization of Robotic Fish with Multiple Control Surfaces

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Mechanical Design and Preliminary Realization of Robotic Fis...

第二十九届中国控制会议

作者： WANG Weibing 1,YU Junzhi 2.WANG Ming 2.DING Rui 2.1.Machine and Electricity Engineering College,Shihezi University,Xinjiang Uygur Autonomous Region 832.03,P.R.China 2.Lab of COMPSYS,institute of Automation,chinese academy of sciences,{2.,P.R.China

This paper deals with the mechanical design and realization of a robotic fish inspired by well-integrated,configurable multiple control surfaces existing in natural *** against the underwater environment and multimodal motion requirements,the principle and mechanical design for artificial control surfaces involving tail plus caudal fin,pectoral s,pelvic fin and dorsal fin are *** preliminary construction and control issues are further outlined.P elimin ry test resul s verify the effectiveness of the proposed *** a well-assembled fishlike propulsive device,not only provides a repeatable test platform for investigating fish-inspired propulsive mechanisms,but also creates a promising high-performance swimming machine.

关键词： Bio-inspired Robots Robotic Fish Mechanical Design Multiple Control Surfaces Swimming Control

HIGH CURIE TEMPERATURE PIEZOELECTRIC SINGLE CRYSTALS Pb(In1/2.b1/2.O3Pb(Mg1/3Nb2.3)O3-PbTiO3 AND THEIR APPLICATIONS IN MEDICAL ULTRASONIC TRANSDUCERS

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HIGH CURIE TEMPERATURE PIEZOELECTRIC SINGLE CRYSTALS Pb(In1/...

2.10全国压电和声波理论及器件技术研讨会

作者： Wei Wang~(*1,2.,Yaoyao Zhang~(1,2.,Xiangyong Zhao~1,Haosu Luo~1 1 Key Laboratory of Inorganic Functional Material and Device,Shanghai institute of Ceramics, chinese academy of sciences,2.5 Chengbei Road,Jiading,Shanghai 2.1800,China 2.Graduate School of the chinese academy of sciences,beijing 100039,China

High Cure temperature and larger coercive field ternary Pb(In1/2.b1/2.O3-Pb(Mg1/3Nb2.3)O3-PbTiO3 (PIN-PMN-PT or PIMNT) single crystals were grown,while maintain comparable piezoelectric properties with *** have designed and prototyped 1.6MHz ultrasonic transducers based on PIN-PMN-PT single crystals,which can be used in transcranial Doppler(TCD) *** with PZT-based TCD probe,the two-way insertion loss achieved by PIN-PMN-PT single crystals-based TCD probe is about 4 dB *** -6dB bandwidth of PIN-PMN-PT single crystal-based transducer is nearly 10%*** improvement of sensitivity and bandwidth of crystal-based probe reveal the great advantages in medical ultrasonic transducers ***,due to the enhanced beam-mode piezoelectric property of PIN-PMN-PT single crystals,the simulation results of ultrasonic phased array based on PIN-PMN-PT as well as PZT-5H ceramic reveal the significant *** 4dB larger sensitivity, 40%shorter impulse response and 2.%broader bandwidth(-6dB) of PIN-PMN-PT single crystal-based will certainly improve medical imaging *** PIN-PMN-PT crystals with large size,ultrahigh piezoelectric properties,good thermal stability,and attractive simulation results may become the promising candidate for medical ultrasonic transducers applications.

关键词： relaxor ferroelectric single crystals PIN-PMN-PT PMN-PT ultrasonic transducer