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Adaptive neural control based on HGO for hypersonic flight vehicles

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science china(Information sciences) 2011年第3期54卷 511-520页

作者： XU Bin 1,2 , GAO DaoXiang 3 & WANG ShiXing 1 1 Department of Computer science and Technology, Tsinghua University, Beijing 100084, china 2 Autonomous System Lab, ETH Zurich Zurich 8092, Switzerland 3 School of Technology, Beijing forestry University, Beijing 100083, china 1. Department of Computer science and Technology Tsinghua University Beijing 100084 China2. Autonomous System Lab ETH Zurich Zurich 8092 Switzerland3. School of Technology Beijing Forestry University Beijing 100083 China

This paper describes the design of adaptive neural controller for the longitudinal dynamics of a generic hypersonic flight vehicle (HFV) which are decomposed into two functional systems, namely the altitude subsystem and the velocity subsystem. For each subsystem, one adaptive neural controller is investigated based on the normal output-feedback formulation. For the altitude subsystem, the high gain observer (HGO) is taken to estimate the unknown newly defined states. Only one neural network (NN) is employed to approximate the lumped uncertain system nonlinearity during the controller design which is considerably simpler than the ones based on back-stepping scheme with the strict-feedback form. The Lyapunov stability of the NN weights and filtered tracking error are guaranteed in the semiglobal sense. Numerical simulation study of step response demonstrates the effectiveness of the proposed strategy in spite of system uncertainty.

关键词： adaptive neural control hypersonic flight vehicle high gain observer output-feedback

Functions and mechanisms of the CBL-CIPK signaling system in plant response to abiotic stress

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Progress in Natural science:Materials International 2009年第6期19卷 667-676页

作者： Ruifen Li a,1, Junwen Zhang a,b,1, Jianhua Wei a, Hongzhi Wanga, Yanzhen Wanga, Rongcai Ma a, a Beijing Agro-Biotechnology Research Center, Beijing Academy of Agriculture and forestry sciences, Beijing 100097, china b Life science College, Capital Normal University, Beijing 100037, china [a]Beijing Agro-Biotechnology Research Center Beijing Academy of Agriculture and Forestry Sciences Beijing 100097 China [b]Life Science College Capital Normal University Beijing 100037 China

To cope with environmental stimuli, plants have evolved precise regulatory mechanisms to perceive, transduce and respond to abiotic stresses that can negatively affect growth and development. The CBL-CIPK signaling system is a newly emerging plant-specific and Ca2+-dependent network mediating abiotic stress tolerance. CBLs may sense a Ca2+ signature triggered by abiotic stresses, and have specific interactions with novel CIPK-type kinases after binding Ca2+. The CBL/CIPK complexes may post-translationally phosphory-late downstream target proteins to regulate abiotic stress tolerance in a cell or tissue-specific manner. In some cases transcription factors are induced to activate stress-responsive genes that control adaptation reactions. The CBL-CIPK signaling system exhibits specificity, diversity and complexity. Meanwhile, cross talk also exists in the CBL-CIPK signaling. To date, significant progress has been made in the role of the CBL-CIPK signaling system in responding to salt, low K+ and to high pH, which will provide a fast and efficient method of molecular design breeding combined with the CBL/CIPK engineering of crop plants, for enhanced tolerance to abiotic stresses. However, more CBL/CIPK components remain to be identified, particularly from specific plants that grow in conditions with abiotic stress, and the specificity of their abiotic stress signaling will need to be dissected.

关键词： Calcium signal CBL CIPK Signal transduction Abiotic stress

NINE NEW SPECIES OF THE GENUS STYLOTERMES FROM china (Isoptera)

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昆虫分类学报 1981年第3期 227-234页

作者： Ping Zhengming Li Guixiang Xu Yueli Liu Yuanzhi Chen Mang Guangdong institute of Entomology Sichuan institute of forestry Chongqing institute of Termite control

The present paper deals with nineteen species of the genus Styloter mes from china, in which some species are revised. They are summarized in the following key, in which nine species are described as new to science. Stylotermes choui is named in honour of Professor Chou Io, Chief Editor of Entomotaxonomia. All type specimens are kept in Guangdong institute of Entomology.

关键词： head length Isoptera NINE NEW SPECIES OF THE GENUS STYLOTERMES FROM china

A Study of Consistency between Land Degradation control Policy and Farmers’ Needs in Western Area, china

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Chinese forestry science and Technology 2009年第4期8卷 1-11页

作者： WAGN Dengju Research institute of forestry Policy and Information, Chinese Academy of forestry, Beijing 100091, P. R. china

The paper chose two counties (Qis) in Inner Mongolia as the research areas to study the policies of conversion of farmland to forest and grazing prohibition and indoor raising implemented in there, which are closely related to the interests of farmers and herdsmen. Based on the investigation and interview among farmer households, the paper analyzed the consistency between land degradation prevention and control policy and the needs of farmers and herdsmen, and finally presented the countermeasures and suggestions which are conducive to improving the effectiveness of land degradation prevention and control policy.

关键词： land degradation conversion of farmland to forest grazing prohibition and indoor raising need farmer decision-making mechanism

Effect of cultivating croplands and grazing in arid grassland habitats on the conservation of melitaeine butterflies in a mountainous area in Northern china

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science china(Life sciences) 2007年第1期50卷 40-46页

作者： WANG YiFei1,2, CHEN JieJun1,3, LIU WenHua1,4 & XU RuMei1 1 Ministry of Education Key Laboratory for Biodiversity science and Ecological Engineering, Beijing Normal University, Beijing 100875, china 2 forestry Research institute, Chinese Academy of forestry sciences, Beijing 100091, china 3 china National Center for Biotechnology Development, Ministry of science and Technology, Beijing 100081, china 4 Center for Disease control and Prevention of Guangdong Province, Guangzhou 510300, china 1. Ministry of Education Key Laboratory for Biodiversity science and Ecological Engineering Beijing Normal University Beijing 100875 China 2. forestry Research institute Chinese Academy of Forestry Sciences Beijing 100091 China 3. china National Center for Biotechnology Development Ministry of Science and Technology Beijing 100081 China 4. Center for Disease control and Prevention of Guangdong Province Guangzhou 510300 China

In the study area (Yanjiaping Village, Hebei Province, china), grazing extensity varies at different loca-tions, small and discontinuous croplands are imbedded in some arid grassland, which are habitats for the melitaeine butterflies, Euphydryas aurinia and Melitaea phoebe. These two species of butterflies coexist in this area, in which grazing and cultivation are the main disturbances. Grazing and cultivation have a reciprocal effect on E. aurinia, rather than M. phoebe. We observed that E. aurinia preferred to occupy patches with moderate grazing and imbedded with small and discontinuous croplands, where E. aurinia also has high population density. The percentage of E. aurinia larval groups in the ribbings was significantly higher than that of M. phoebe, whereas larvae of both species tended to increase in recent years. Our data also showed that the population density and the patch occupancy rate of both E. aurinia and M. phoebe were the highest under moderate grazing. It indicates that cultivation of small and dis-continuous croplands within the patch has a significant effect on the population density of both spe-cies of melitaeine butterflies. Thus, to artificially create or maintain semi-natural habitats, comple-mented by moderate grazing, might be an ecological strategy to conserve melitaeine butterflies effec-tively. Considering the distinct impacts of cultivation and grazing on the population distribution and dynamics of the two different species, human disturbance in the mountainous area might be strategi-cally involved in proposing conservation plans for the target species in the future.

关键词： grazing croplands metapopulation conservation Euphydryas aurinia Melitaea phoebe

Performance characterization of rigid polyurethane foam with refined alkali lignin and modified alkali lignin

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Journal of forestry Research 2009年第2期20卷 161-164页

作者： LIU Zhi-ming, YU Fei, FANG Gui-zhen, YANG Hui-jun Key Laboratory of Bio-based Material science and Technology, Ministry of Education, Northeast forestry University, Harbin 150040, P.R.china Key Laboratory of Bio-based Material science and Technology Ministry of Education Northeast Forestry University Harbin 150040 P.R. China

The two kinds of rigid polyurethane(PU) foams were prepared with respectively adding the refined alkali lignin and alkali lignin modified by 3-chloro-1,2-epoxypropane to be instead of 15% of the polyether glycol in *** indexes of mechanical performance, apparent density, thermal stability and aging resistance were separately tested for the prepared PU *** results show that the mechanical property, thermal insulation and thermal stability for PU foam with modified alkali lignin are excellent among two kinds of PU foams and control *** additions of the refined alkali lignin and modified alkali lignin to PU foam have little effect on the natural aging or heat aging resistance except for decreasing hot alkali resistance ***, the thermal conductivity of modified alkali lignin PU foam is lowest among two kinds of PU foams and control *** alkali lignin PU foam modified by 3-chloro-1,2-epoxypropane could be applied in the heat preservation field.

关键词： refined alkali lignin modified alkali lignin rigid PU foam mechanic performance thermal stability

Response of Tomato Plants to a New Application Method of Polyolefin-Coated Fertilizer

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Pedosphere 2005年第4期15卷 491-498页

作者： TIAN Xiao-Hong M. SAIGUSA Laboratory of Environmental Crop science Field Science Centre Tohoku University Kawatabi Naruko Miyagi Prefecture 989-6711 （Japan）. College of Natural Resources and Environmental sciences Northwest Science and Technology University of Agriculture and Forestry Yangling Shaanxi 712100 （China）

The response of tomato （Lycopersicon esculentum） plants basically fertilized with 0.3 g N per plant of compound fertilizer with a N：P2O5：K2O ratio of 20：10：20 to sticks of polyolefin-coated fertilizer （POCF）（LongT0 with a N：P2Os：K2O ratio of 14：12：14） applied 23 d after transplanting was investigated using rooting boxes in the greenhouse. The results at 26 and 40 d after stick fertilizer treatment showed that the use of the stick fertilizer greatly increased the production of many new fine roots from the tomato plants. Compared to the unfertilized control, root length and root length density in the stick fertilizer treatment increased by 3.6-6.7 fold. In the soil zones near the stick fertilizer, root weight and root mass density were also significantly higher for the stick fertilizer treatment. Additionally, the use of the stick fertilizer increased the N, P and K concentrations in the leaves and stems of the tomato plants. The new fine roots growing near the stick fertilizer not only absorbed more nutrients and translocated them to the shoots, but also contained more nutrients within themselves. The soil ammonium and nitrate N data showed that N released from the stick fertilizer played a major role in inducing the production of new fine roots. These results indicated that stick fertilizer could be used as an alternative to the co-situs application technique to change and control the root distribution of crops as well as to increase the potential capacity of roots for water and nutrient absorption.

关键词： application method controlled release fertilizer tomato (Lycopersicon esculentum)

EVALUATION ON ECOLOGICAL ADAPTABILITY AND WEED control OF SEVEN COVER PLANTS IN CHESTNUT(CASTANEA MOLLISSIA) ORCHARD OF BEIJING

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EVALUATION ON ECOLOGICAL ADAPTABILITY AND WEED CONTROL OF SE...

Application of Public-Private Partnership in Land Degradation control and A Case Study

中国第三届植物化感作用学术研讨会、第八届全国杂草科学大会、联合国粮农组织——中国“水稻化感作用论坛”

作者： Xiang-yang LU and Jun XU institute of Plant & Enviromenlal Protection,Beijing Academy of Agricultural and forestry science,Beijing 100089,china

Ecological adaptability of 6 cover crops and their effectiveniss of controlling weeds was evaluated in Chestnut(Castanea Mollissia) orchard of Beijing in order to replace herbicide, avoid bare soil,reduce soil erosion by water and increase plant *** repens, Dactylis glomerata,Festuca arundinacea,Lolium perenne,Poa pratensis and Bromus inermis

关键词： CASTANEA MOLLISSIA EVALUATION ON ECOLOGICAL ADAPTABILITY AND WEED control OF SEVEN COVER PLANTS IN CHESTNUT ORCHARD OF BEIJING

来源： cnki会议评论

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Chinese forestry science and Technology 2011年第4期10卷 1-10页

作者： Wang Dengju Chen Jie Research institute of forestry Policy and Information, Chinese Academy of forestry, Beijing 100091, P. R. china

The paper reviewed the background of public-private partnership (PPP) development, described PPP concept, characteristics and basic models, and analyzed the necessity and feasibility to develop land degradation control PPP. Then the experiences that Elion Resources Group in Inner Mongolia has accumulated in Kubuqi Desert control and development as well as the revelations were summarized with the hope to provide reference for establishing land degradation control PPP in arid area of western region.

关键词： land degradation public-private partnership characteristic model experience revelation