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Application of Genetic Algorithms in Identification ofLinear Time-Varying System

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 58-62页

作者： Zhichun Mu KeLiu Zichao Wang Datai Yu D. Koshal D. Pearce Information Engineering School, University of science & Technology beijing, beijing 100083, china School of Engineering, University of Brighton, Brighton, UK Univ Sci & Technol beijing Informat Engn Sch Beijing 100083 Peoples R China Brighton Univ Sch Engn Brighton E Sussex England

By applying genetic algorithms (GA) to on-line identification of linear time-varying systems; a number of modifications are made to the Simple Genetic Algorithm to improve the performance of the algorithm in identification applications. The simulation results indicate that the method is not only capable of following the changing parameters of the system, but also has improved the identification accuracy compared with that using the least square method.

关键词： genetic algorithm, system identification linear system

D构象丝氨酸在中枢神经系统中的功能研究进展

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生物化学与生物物理进展 2003年第6期30卷 852-854页

作者：阳洪波袁建刚彭小忠中国医学科学院基础医学研究所中国协和医科大学基础医学院医学分子生物学国家重点实验室北京100005

哺乳动物中枢神经系统中 D 构象丝氨酸的区域性高浓度分布与N 甲基 D 天冬氨酸 (NMDA)受体相一致 .它主要由丝氨酸消旋酶将 L 丝氨酸直接消旋而来 ,也可能通过肠道菌群产生后吸收至体内 ,最终被 D 构象氨基酸氧化酶氧化 .这种从胶质细... 详细信息

哺乳动物中枢神经系统中 D 构象丝氨酸的区域性高浓度分布与N 甲基 D 天冬氨酸 (NMDA)受体相一致 .它主要由丝氨酸消旋酶将 L 丝氨酸直接消旋而来 ,也可能通过肠道菌群产生后吸收至体内 ,最终被 D 构象氨基酸氧化酶氧化 .这种从胶质细胞而非神经元来源的“异常”构象氨基酸作为一种新型神经递质 ,不仅更新了传统“神经递质”的定义。

关键词： D构象丝氨酸丝氨酸消旋酶 NMDA受体中枢神经系统功能

Effect of iron on growth and lipid accumulation in Chlorella vulgaris

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Effect of iron on growth and lipid accumulation in Chlorella...

Symmetry－breaking　Subharmonic　Bifurcationsof　Periodicaly　Parameter－excited　systems

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： Zhi-Yuan Liu~(a,c) Guang-Ce Wang~(ab*) Bai-Cheng Zhou~a a institute of Oceanology,chinese academy of sciences,Qingdao 266071,P.R.china b CoUeage of Oceanology,Tianjin University of science Technologys,Tianfin 300222,P.R.china c Graduate School,chinese academy of sciences,beijing 100039,P.R.china

Due to the shortages of fossil fuels and the production of greenhouse gas carbon dioxide on their combustion,using microalgae as a source for bio-fuel is receiving considerable attention again in recent *** are one of the more promising sources because they do not compete with food crops and thus minimising the damages caused to the eco-and food chain systems. Marine microalgae Chlorella vulgaris is consider being a good potential source for biodiesel production due to its faster growth and easier cultivation except for the lower lipid content(about 14% to 20 % by weight of dry biomass).In order to increase the lipid content and cell density in Chlorella vulgaris,the effect of iron on growth and lipid accumulation in cells were *** high level of iron concentration in the initial substrate,the cellular lipid content was up to 56.6% of biomass weigh and was 3 to 7-fold that of other cultures under lower iron *** additions of Feconcentration ranged from 1.2×10to 1.2× 10mol Lin the initial mediums were considered to be optimal for growth. Supplementing 1.2×10or 1.8×10tool LFeCl in the late growth phase increased the final cell density but did not induce lipid accumulation in cells. Moreover,the rapid method to determine the lipid accumulation in microalgae with fluorescence spectrophotometer was established. Our results showed that marine strain *** could be used as a resource for biodiesel production by adjusting iron concentration in the initial medium. Supplementing chelated Fealone in the late exponential growth phase would be enough for increasing the biomass production in ***.

关键词： microalgae Chlorella vulgaris cell densities lipid fluorescence fluorescence spectrophotometer FeCl3

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Communications in Nonlinear science and Numerical Simulation 1996年第4期 6-8页

作者： Guowei HE 1 Laboratory for Nonlinear Mechanics, institute of Mechanics, chinese academy of science, beijing, 10080, china 2 Service d’Astrophysique, CE-Saclay, L’orme des Merisiers 709, 91191, Gif sur Yvette, France E-mail: he@discovery

Ｓｙｍｍｅｔｒｙ－ｂｒｅａｋｉｎｇＳｕｂｈａｒｍｏｎｉｃＢｉｆｕｒｃａｔｉｏｎｓｏｆＰｅｒｉｏｄｉｃａｌｙＰａｒａｍｅｔｅｒ－ｅｘｃｉｔｅｄＳｙｓｔｅｍｓ１１ＴｈｅｐａｐｅｒｗａｓｒｅｃｅｉｖｅｄｏｎＡｕｇ．３０ｔｈ... 详细信息

Ｓｙｍｍｅｔｒｙ－ｂｒｅａｋｉｎｇＳｕｂｈａｒｍｏｎｉｃＢｉｆｕｒｃａｔｉｏｎｓｏｆＰｅｒｉｏｄｉｃａｌｙＰａｒａｍｅｔｅｒ－ｅｘｃｉｔｅｄＳｙｓｔｅｍｓ１１ＴｈｅｐａｐｅｒｗａｓｒｅｃｅｉｖｅｄｏｎＡｕｇ．３０ｔｈ，１９９６ＧｕｏｗｅｉＨＥ１Ｌａｂ...

关键词： Symmetry-breaking Subharmonical bifurcation.

Evolution and Prospect of china's Regional Planning

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china City Planning Review 2007年第2期16卷 40-48页

作者： HU Xuwei, Researcher, Center of Regional & Urban Planning, institute of Geographic science and Natural Resources, china academy of science, beijing, P. R. china.QIAN Fang

1. Retrospection on historyAs important section of spatial planning, regional planning is attracting increasing attentions from the governments and the society in china, for its undeniable influ-ence on space administ... 详细信息

关键词： administration speaking attracting municipal provi

Therapeutical effect of Shengmaisan is determined by the interaction among the three herbs

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Progress in Natural science:Materials International 2003年第5期 16-20页

作者： TAO Dongliang, XU Yizhuang, ZHENG Aiguo, HUANG Baogui, LI Saijun, HE Xiaoran, WENG Shifu, XU Xiaojie, WU Jinguang , GUO Fanxiu and XU Duanfu (1. State Key Laboratory of Rare Earth Materials Chemistry and Applications, Peking University, beijing 100871, china 2. institute of Chemistry, chinese academy of sciences, beijing 100080, china) State Key Laboratory of Rare Earth Materials Chemistry and Applications Peking University Beijing 100871 China institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

Shengmaisan is a recipe of traditional chinese medicine, which is composed of three herbs. The interaction among the components from the three herbs of Shengmaisan is investigated using FT-IR, Matrix Assistant Laser Desorption/Ionization Time of flight mass spectrometry (MALDI TOF MS) and TEM observation. Interactions among various components from different herbs cause enhancement of the solubility of some component and suppression of the solubility of others. Results from MALDI-TOF MS show that some components found in the decoction from a single herb disappear when different herbs are decocted together. On the other hand, new substances are produced when two and/or three herbs of Shengmaisan are decocted together. TEM showed that vacuoles formed in the decoction from two and/or three herbs of Shengmaisan but did not occur in any decoction from a single herb. This result provides us direct evidence that the solubilized structure is formed by the interaction among the components from different herbs. Th

关键词： TEM FT-IR Shengmaisan interaction.

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内侧颞叶系统在知觉启动中的作用及其机制

心理学报 2003年第6期35卷 761-766页

作者：杨炯炯翁旭初管林初匡培梓张懋植孙伟建于生元北京大学心理学系北京100871 中国科学院心理研究所北京100101 首都医科大学附属北京天坛医院神经外科北京100050 中国人民解放军307医院神经外科北京100853 中国人民解放军总医院神经内科北京100853

以 1 1例内侧颞叶 (MTL)损伤病人为被试 ,探讨MTL与知觉启动的关系及其内在机制。被试依次完成学习颜色词、快速词命名和再认任务。在实验 1的词命名中包括旧词、重组颜色词和新词 ,结果表明 ,MTL损伤病人没有表现出旧词的命名时间短于... 详细信息

以 1 1例内侧颞叶 (MTL)损伤病人为被试 ,探讨MTL与知觉启动的关系及其内在机制。被试依次完成学习颜色词、快速词命名和再认任务。在实验 1的词命名中包括旧词、重组颜色词和新词 ,结果表明 ,MTL损伤病人没有表现出旧词的命名时间短于重组颜色词的现象 ,颜色启动效应受损 ,其再认成绩也低于正常被试。但是当用新颜色词代替重组颜色词后 (实验 2 ) ,MTL损伤病人读旧词的时间明显短于新颜色词 ,颜色启动与正常对照组之间没有明显差别 ,但他们的再认成绩仍比对照组低。这表明 ,当任务要求被试加工项目与其特性之间的关系时 (词与颜色 ) ,MTL损伤对启动效应会有影响。

关键词：启动效应记忆联结捆绑内侧颞叶

Magnetostratigraphic age of the Xiantai Paleolithic site in the Nihewan Basin and implications for early human colonization of Northeast Asia

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Magnetostratigraphic age of the Xiantai Paleolithic site in ...

施肥与水体环境质量——论施肥对环境的影响(2)

中国科学院地质与地球物理研究所2006学术年会

作者： Chenglong Deng~a,Qi Wei~b,Rixiang Zhu~a,Hongqiang Wang~a,Rui Zhang~a,Hong Ao~a,Liao Chang~c, Yongxin Pan~a a Paleomagnetism and Geochronology Laboratory(SKL-LE),institute of Geology and Geophysics,chinese academy of sciences,beijing 100029,china b institute of Vertebrate Paleontology and Paleoanthropology,chinese academy of sciences,beijing 100044, china c School of Ocean and Earth science,University of Southampton,Southampton SO14 3ZH,UK

Timing of the early habitation and stone technologies in the Nihewan Basin,North china has provided insights into our understanding of early human adaptability to high northern latitudes in East *** we contribute to this topic with detailed magnetostratigraphic investigation,coupled with mineral magnetic measurements and palynological analyses on a lacustrine sequence in this basin,which contains the Xiantai Paleolithic *** and hematite were identified as the main carriers for the characteristic remanent magnetizations. Magnetostratigraphic results show that the Xiantai lacustrine sequence recorded the Brunhes chron,the Jaramillo and the Olduvai subchrons,and successive reverse polarity portions of the intervening Matuyama *** correlation in terms of lithology,magnetic susceptibility and magnetic polarity sequences between the Xiantai and Xiaochangliang sections indicates that the Xiantai artefact layer is readily contemporary with the Xiaochangiiang artefact layer,which has been previously estimated to be about 1.36 Ma[***,***,***, ***,***,***,***,***,***,***,***,Earliest presence of humans in northeast Asia,Nature 413(2001) 413-417.[1]].Early humans of the Xiantai Paleolithic site lived in a steppe paleoenvironment indicated from fossil pollens. Furthermore,the combined evidence of our magnetostratigraphy and previously published magnetochronology and paleoclimate data documents that early humans of North china were able to adjust to an increasing variability of paleoclimates and paleoenvironments over the Early Pleistocene.

关键词： magnetostratigraphy Xiantai Paleolithic site Nihewan Basin Early Pleistocene human evolution

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土壤 2003年第5期35卷 353-363页

作者：曹志洪中国科学院南京土壤研究所南京210008

氮肥施用过量,无论是无机N肥或有机肥都会在土壤中积累.特别是栽种浅根系和小根系的蔬菜地,土壤累积的NO3--N能淋洗到地下水使NO3-超标.在种植深根系和有较大根系的作物如稻、麦、玉米和棉花等大田粮食和经济作物的土壤,目前的施肥水平... 详细信息

氮肥施用过量,无论是无机N肥或有机肥都会在土壤中积累.特别是栽种浅根系和小根系的蔬菜地,土壤累积的NO3--N能淋洗到地下水使NO3-超标.在种植深根系和有较大根系的作物如稻、麦、玉米和棉花等大田粮食和经济作物的土壤,目前的施肥水平下尤其在作物生长期内一般不会有NO3-积累,也不可能污染地下水.地表水体中85%以上是NH4+-N,主要来源于人畜粪尿和有机肥,不是源于当季施入的无机N肥.保护水环境质量的重点应放在控制畜禽养殖业污染和城乡生活污水等非点源污染的治理上.温带地区大多数地表水体富营养化的限制因子是P.有机肥和无机P肥过量使用都会使土壤P不断累积.据在苏南太湖地区的调研证明,P素非点源污染中,农田进入水体的P(含水体下淤泥扩散的P)的相对贡献率不到10%,而畜、禽、人排泄物及生活污水、淡水养殖业等P的相对贡献率在90%左右.农田P进入水体的冬麦季比稻季多2～3倍.旱地中以蔬菜基地土壤P素累积最多(蔬菜基地多数在城市近郊)对水体污染威胁最大.为此,建议蔬菜基地最好从近郊迁移到较远的地区,该区种植结构可作相应调整.从经济效益、社会效益和生态效益综合考虑,保持足够面积的稻田,压缩冬麦面积,部分改种油菜或其它经济作物;部分种牧草养鹅,增加农民收入满足市场需求;部分种冬绿肥是可取的.

关键词：施肥地下水 NO3-N 地表水富营养化