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Characterization of plastic flow in two Zr-based bulk metallic glasses

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science China(Technological sciences) 2006年第4期49卷 414-424页

作者： XING Dongmei1,2, ZHANG Taihua1, LI Weihuo3.& WEI Bingchen3.1. State Key Laboratory of Nonlinear Mechanics (LNM), Institute of Mechanics, Chinese Academy of Sci- ences, beijing 100080, China 2. college of Physics and Electronic information {3., Tianjin normal university, Tianjin 3.0074, China 3. National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of {3.s, beijing 100080, China 1. State Key Laboratory of Nonlinear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China 2. college of Physics and Electronic information science Tianjin Normal University Tianjin 300074 China 3. National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

Plastic deformation behaviors of Zr65Al10Ni10Cu15 and Zr52.5Al10Ni10Cu15Be12.5 bulk metallic glasses (BMGs) are studied by using the depth-sensing nanoindentation, microindentation and uniaxial compression. The Be-containing BMG exhibits a signifi- cantly improved overall plastic strain compared with the Be-free alloy during compressive tests. Both BMGs show a loading-rate-dependent serrated flow during nanoindentation measurements, but the Be-containing alloy exhibits a much lower critical loading rate for the disappearance of the serration than the Be-free BMG. The shear band patterns de- veloped during plastic deformation are investigated by microindentation technique, wherein much higher shear band density is found in the Be-containing alloy than in the Be-free alloy, indicating an easier nucleation of shear bands in the former BMG. The dif- ference in the plastic deformation behavior of the two BMGs can be explained by a free volume model.

关键词： Bulk metallic glass, plastic deformation, shear band, nanoindentation.

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 {3., 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 1. State Key Laboratory of Remote Sensing science Institute of Remote Sensing Applications Chinese Academy of Sciences 100101 Beijing China 2. Geography and Environment college Jiangxi Normal University 330027 Nanchang China 3. Graduate university of Chinese Academy of sciences 100039 Beijing China 4. beijing Research Institute of Uranium Geology 100875 Beijing China 5. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing 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.

Using remote sensing to research beijing wetlands dynamics

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science China(Technological sciences) 2006年第z2期49卷 97-107页

作者： ZHAO Wenji, GONG Zhaoning, GONG Huili, LI Xiaojuan, ZHANG Songmei & LI Jing Key Lab of Resource Environment and GIS of beijing, Capital normal university, beijing 10003., China Northeast Institute of Geography and Agroecology, Chinese Academy of sciences, Changchun 13.012, China college of Resources science and technology, beijing normal university, beijing 100875, China Capital normal Univ Key Lab Resource Environm Beijing 100037 Peoples R China Capital normal Univ GIS Beijing Beijing 100037 Peoples R China Chinese Acad Sci NE Inst Geog & Agroecol Changchun 130012 Peoples R China beijing normal Univ Coll Resources Sci & Technol Beijing 100875 Peoples R China

In beijing, where wetlands are important to municipal freshwater conservation and biodiversity retention, three different types of wetlands were identified: riverside wetlands, wetlands surrounding lakes and reservoirs, and wetlands in municipal *** sensing technology was applied in combination with field investigations to monitor and analyze the changes in these wetlands, and a combination of fusion technologies,Landsat TM/ETM+ and IKONOS imaging, was used to investigate and map them. This study indicates that not only have wetland areas been reduced by half, but also their ecological environments have been degraded because of rapid economic development and population increase. Suggestions based on this research are made to reconstruct the ecological environment of the wetlands and return them to their previous state.

关键词： beijing, wetland resource, remote sensing technology, ecological environment, dynamics.

Fuzzy controllers based on some fuzzy implication operators and their response functions

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Progress in Natural science:Materials International 2004年第1期14卷 16-21页

作者： LI Hongxing 1*, YOU Fei 1 and PENG Jiayin 2(1. Department of Mathematics, beijing normal university, beijing 100875, China 2. Department of Mathematics, Neijiang Teacher's college, Neijiang 641112, China) beijing normal Univ Dept Math Beijing 100875 Peoples R China

The fuzzy controllers constructed by 23.fuzzy implication operators based on CRI algorithm and their response functions are discussed. The conclusions show that the fuzzy controllers constructed by 9 fuzzy implication operators are universal approximators to continuous functions and can be used in practical fuzzy control systems. And these 9 fuzzy implication operators except for Einstein operator intersection are all the adjoint pairs of some fuzzy implication operators. Besides, there are 3.other fuzzy controllers formed by fuzzy implication operators being regarded approximately as fitted functions.

关键词： fuzzy implication operators CRI algorithm fuzzy controllers response functions universal approximators

A high-resolution late Pleistocene record of pollen vegetation and climate change from Jingning, NW China

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science China Earth sciences 2006年第2期49卷 154-162页

作者： LI Chunhai12, TANG Lingyu1, FENG Zhaodong3.4, ZHANG Hucai2, WANG Weiguo3.& AN Chenbang3.1. Nanjing Institute of Geology and Palaeontology, Chinese Academy of sciences, Nanjing 210008, China 2. Nanjng Institute of Geography and Limnology, Chinese Academy of sciences, Nanjing 210008, China 3. Environment and Resources college, Lanzhou {3., Lanzhou 73.000, China 4. beijing normal university, beijing 100875, China 1. Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Nanjng Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China 3. Environment and Resources college Lanzhou University Lanzhou 730000 China 4. beijing normal university Beijing 100875 China

With the support of 18 AMS-14C data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 44.2 to 11 ka B.P. in the Jingning area. Over the period of 44―29 ka B.P. (MIS3., coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 23.ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3. further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.

关键词： Western Loess Plateau, pollen record, climatic change, late Pleistocene.

Formal Verification under Unknown Constraints

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Wuhan university Journal of Natural sciences 2005年第1期10卷 43-46页

作者： LI Guang-hui 1,2,3., LI Xiao-wei 2,3.. School of information Engineering, Zhejiang Forestry college, Hangzhou 3.13.0, Zhejiang, China 2. Institute of Computing technology, Chinese Academy of {3.s, beijing 100080, China 3. Graduate School of the Chinese Academy of {3.s, beijing 10003., China School of information Engineering Zhejiang Forestry College Hangzhou 311300 Zhejiang China

We present a formal method of verifying designs with unknown constraints (e.g., black boxes) using Boolean satisfiability (SAT). This method is based on a new encoding scheme of unknown constraints, and solves the corresponding conjunctive normal form (CNF) ***,this method can avoid the potential memory explosion, which the binary decision diagram (BDD) based techniques maybe suffer from, thus it has the capacity of verifying large designs. Experimental results demonstrate the efficiency and feasibility of the proposed method.

关键词： formal verification unknown constraints black box Boolean satisfiability Boolean comparison

An Intelligent Otologic Drill

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Journal of Otology 2010年第2期5卷 104-110页

作者： SHEN Peng1,FENG Guo-dong2,CAO Tian-yang 3.GAO Zhi-qiang 2,LI Xi-sheng 3.1 Department of Otolaryngology,Chuiyangliu Hospital of beijing 2 Department of Otolaryngology,Peking Union Medical college Hospital,Chinese Academy of Medical sciences and Peking Union Medical college,beijing,China 3.School of information & Engineering,university of science and technology beijing,beijing,China Department of Otolaryngology Chuiyangliu Hospital of Beijing Department of Otolaryngology Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China School of information & Engineering University of Science and Technology Beijing Beijing China

Objective To test a modified otologic drill under different drilling conditions for its ability to identify drilling faults and stop *** Based on force analysis and previous works,an otologic drill was modified and equipped with three *** various conditions,the drill was used to simulate three drilling faults and normal drilling,and signals from the drill were analyzed to extract the characteristic signal.A multi-sensor information fusion system and a stop program were designed to recognize drilling faults and stop *** Signals from each sensor changed consistently in response to drilling condition changes,with high repeatability and *** average identification rate was 72.625%,68.575%,70.5% and 81.3. respectively for the three simulated drilling faults and normal *** stop program stopped drilling in 0.2～ 0.3.seconds when a drilling faults was *** This study shows that the forces acting on the drill bit change predictably in the three simulated drilling conditions;that using suitable BP neural networks,the drilling faults can be reliably identified,and that a stop program based upon characteristic signal recognition can stop drilling quickly upon detecting drilling *** lays a foundation for development of a system capable of predicting drilling faults and automatic drill *** studies are being undertaken for practical application of such a system.

关键词： drill otologic surgery force sensor back propagation(BP) neural network

The effects of proteasome inhibitor lactacystin on mouse oocyte meiosis and first cleavage

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science China(Life sciences) 2005年第3期48卷 287-294页

作者： TAN Xin 1,3., PENG An 2 , WANG Yongchao 2 & TANG Zuoqing 3.1. School of Life sciences and technology, beijing Institute of technology, beijing 100081, China 2. college of Life sciences, beijing normal university, beijing 100875, China 3. college of Basic Medicine, Capital university of Medical sciences, beijing 100054, China 1. School of Life sciences and technology Beijing Institute of Technology 100081 Beijing China 2. college of Basic Medicine Capital University of Medical Sciences 100054 Beijing China 3. college of Life sciences Beijing Normal University 100875 Beijing China

In order to study the effects of ubiquitin-proteasome pathway (UPP) on mouse oo- cyte meiosis and cleavage, oocytes undergoing maturation and parthenogenetic activation and 1-cell embryos were treated with lactacystin, a specific inhibitor of proteasome. The results indi- cated that the rate of GVBD was not influenced by the treatment, but polar body extrusion, par- thenogenesis and first cleavage were inhibited. Immunofluorescent staining using anti β-tubulin antibody indicated that the continuous treatment of lactacystin from GV stage disorganized microtubules and spindle assembly. When metaphase stage oocytes were treated with the drug, the already formed spindle structure was not affected , but the oocytes were arrested at meta- phases. The 1-cell embryos were arrested at interphase or metaphase of first mitosis when they were incubated in the drug. Proteasome regulatory subunit PA700 was located in the spindle region, as indicated by immunofluorescence. These results suggest that UPP has effects on the process of oocyte meiosis and early cleavage in many aspects, including normal organization of spindle at prophase and segregation of chromosomes at anaphase for normal meiosis.

关键词： proteasome, oocyte, meiosis, cleavage.

Overexpression of proto-oncogene bcl-2 in rheumatoid synovium

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Chinese science Bulletin 1997年第24期42卷 2087-2090页

作者： LIANG Haiying, WANG Yongchao, CHEN Zhiqiang, CHEN Huanmian and JIANG Ming Division of Rheumatology, Peking Union Medical college Hospital, beijing 100073. China 2. Key Laboratory of Cell Prolifer ation and Regulation Biology, beijing normal university,{3., China Division of Rheumatology Peking Union Medical College Hospital Beijing 100073 China

RHEUMATOID arthritis (RA) is an autoimmune disease which progressively and systematicallyinvades the joints of bones. A severe chronic situation may lead to the damage of cartilages,bones and tendons and eventually handicap the patients. One of the main histopathological fea-tures of rheumatoid synovium is a marked increase of the thickness and the number of cells inthe synovial lining layer. It is well known that the synovial lining cells secrete many cell fac-

关键词： rheumatoid synovium synovial lining cells bcI-2 apoptosis.