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Design and Analysis of Outer Baffle of Space Telescope

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Design and Analysis of Outer Baffle of Space Telescope

DESIGN AND COMPILATION OF AGRICULTURAL ELECTRONIC ATLAS AT COUNTY-LEVEL

2010 The 3rd International Conference on Computational Intelligence and Industrial Application (PACIIA2010)

作者： Yingjun Guan and Deqiang Mu School of Mechatronic Engineering changchun University of Technology changchun jilin province china Zhilai Li Department of Space Optics CIOMP changchun jilin province china

Stray light prevention of space telescope to improve the imaging quality plays a vital role. Through the outer baffle is properly set can effectively restrain the stray light. In order to satisfy the requirements of lightweight,high stiffness,high strengthen and high dimensional stability,carbon fiber composite material was selected as the outer baffle of space telescope materials. A design idea of independent installation of outer baffle and main support structure of space telescope was proposed,thus the influence on the optical elements by outer baffle was reduced extremely. By adopting finite element analysis technique,thermal and dynamic characteristics of outer baffle were analyzed detailed and the structure parameters were optimized. The final design scheme shows that the mass is 5.2 kg and the first order natural frequency is 113 Hz. Dynamic test results indicate that the first order natural frequency is 106.8 Hz,the magnification of acceleration response is less 10 times and the maximum stress is 86.6MPa in the sinusoidal and random vibration test,which meet the design requirements.

关键词： space telescope TMA outer baffle finite element method dynamic experiment

来源： cnki会议评论

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Chinese Geographical science 2001年第3期11卷 87-91页

作者： ZHU Jin-hua(changchun institute of Geography,t he Chinese Academy of sciences,changchun 130021,P.R.china)A changchun institute of Geography the Chinese Academy of Sciences Changchun P. R. China

:With the rapid development and application of new techniques,cartograp hy has entered the 21st centu-ry’s digital period from computer-a ssist mapping in the 1970s,traditio nal map representation has transformed from 2-D,mono-medium,static into 3-D,multi-media,dynamic and network(including internet),and gradually is developing to-wards 4-D(time,space).There appeared digital map,electr onic map,soft map,hard map,interac tive map,mingle map *** map needs to in clude much more contents in 3-D,multi-media than other types of *** electron-ic mapcanrepresentcompletely these *** agricultural electronic atlas atcounty-levelaims to reflectscientifi-cally china’s modernization agricu lture development level,the new ach ievements of agricultural science a nd *** electronic atlas at county-level should take“sustainable development as the theme;systematically reflec t the natural resources and natural en vironment in a county;the spatial an d temporal distribution and changin g lawof agricultur-al resources(including climate,soil and water).In the paper the authors introduce t he concrete contents of agricultura l electronic atlas,their compilatio n process,and corresponding software and hard ware as well as an *** agricul tur-al electronic atlas design the most advanced multi-media techniques must be *** procedure of agricultu ral electron-ic atlas includes the study on compilation aim,content selection analysis,overall framework and data organ ization,determin-ing compilation *** re includes many contents;each county has its own *** designing we set up a county’s theme according to its con crete situation,the atlas contents are selected around the *** example,the main problems faced by the agricultu re of Da’an City in jilin province is l and desertification,so land desertification and its control are the theme of agricult ural electronic atlas of Da’an *** we compile other cou

关键词： agriculturalelectronic mapatcounty-level designofelectronic map compilationofelectronic map agricul-tural electronic atlas

APPLICATION OF PROBABILITY WAVE IN LONG-RANGE SEASONAL PREDICTION

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Acta Meteorologica Sinica 1988年第3期 371-379页

作者：章少卿李麦村朱其文 Observatory of jilin province changchun institute of Atmospheric Physics Academia Sinica Beijing jilin Research institute of meteorological science

It is discussed that the anomaly in long-range weather is due to the stable sustained *** monthly or seasonal departure maps can essentially be regarded as probability waves which reflectthe anomaly distribution of heat sources and sinks on the earth’s *** persistent stable circulationcreats these distributions which serve as persistent disturbance sources and in turn feedback the generalcirculation with persistent stability in later *** departure probability waves on a six-month (September—February)chart reflect the anomalous dis-tribution of heat sources and sinks on the underlying *** waves north of 30°N move slowly andeastward on the Eurasian Continent against the temperature gradient,while they are stationary south of 30°N.A statistical model is developed to predict the spring—summer temperature and precipitation of next yearby using the six-month departure probability wave of last *** 1982--1985 it was tested in severalprovinces of northern china with encousaging results.

关键词： APPLICATION OF PROBABILITY WAVE IN LONG-RANGE SEASONAL PREDICTION

POSSIBILITY TO USE SCH(?)RDINGER EQUATION TO DESCRIBE LARGE-SCALE PROBABILITY WAVES AND ITS APPLICATION IN SEASONAL PREDICTION

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Acta meteorologica Sinica 1989年第1期3卷 25-33页

作者：章少卿李麦村朱其文 Observatory of jilin province Changchun institute of Atmospheric Physics Academia SinicaBeijing jilin Research institute of meteorological Scicnce Changchun

Under the influence of a one-dimensional stationary outfield with the equilibrium between kinetic and potential energy produced by it,a modified Sch(?)rdinger equation in the form i((?)ψ/(?)t)t=a (?)~2ψ/ax^2-ib (?),where b=b_o(?)T/(?)x,is used to describe the behavior of the probability wave on the six-month departure charts at the 500 hPa *** is found that C=2πa/L-b_o(?)T/ax and when L→∞,then C= -b_o(?)T/(?)x,where C is wave velocity,a and b are constants,and L is *** motion direction of probability waves is against the outfield temperature gradient,and their velocity is related to the absolute value of temperature *** motion of waves shrinks in heat sinks and expands in heat sources,which have been verified in *** the six-month departure probability wave and the modified Sch(?)rdinger equation are used in the MOS predictions of temperature and rainfall in spring-summer 1981-1985 in jilin province and the accuracy for trend predictions is equal to 80%.

关键词： RDINGER EQUATION TO DESCRIBE LARGE-SCALE PROBABILITY WAVES AND ITS APPLICATION IN SEASONAL PREDICTION POSSIBILITY TO USE SCH than

ANALYSIS ON SPATIAL DIFFERENCE OF LAND USECHANGE BASED ON PHYSICAL AND CULTURALLANDSCAPE ATTRIBUTES──A Case Study at Mongolian AutonomousCounty of Qian Gorlos, jilin province

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Chinese Geographical science 2001年第1期11卷 50-56页

作者： HUANG Fang, LIU Xiang-nan, XU Hong-mei, ZHANG Shu-wen, ZHANG Yang-zhen (changchun institute of Geography, the Chinese Academy of sciences, changchun 130021, P. R. china School of Urban and Environmental science, Northeast Normal University, changchun 13 changchun institute of Geography the Chinese Academy of Sciences Changchun P. R. China School of Urban and Environmental science Northeast Normal University Changchun P. R. China institute of Resources science Beijing Normal University Beijing P. R. China

Land use changes are regarded as landscape pattern change driven by many interactive natural and social-economic factors. Different combination of physical geographical elements induced the difference of spatio-temporal pattern of land use change. There are four physical geographical regions in Mongolian Autonomou County of Qian Gorlos of jilin province. Based on spatial analysis and statistical analysis, we conclude that the primary pattern of land use and the tendency of land use changes are all different in four physical geographical regions. During 1987 – 1996, the dominant land use change processes were from grassland or forest to arableland, from unused land to paddy and grassland to unused land. Though land use change is mainly affected by social and economic condition in short period, the composite characters of physical geographical elements controls land use dynamic process. The relationship between land use dynamic process and the character of physical geographical units differ in different regions. Possible human impacts on land use change are explored with application of buffer areas of series distance along main roads and radius around main settlements. A few models are built to describe the relationship between land use spatial change rates and distance to road and settlements. According to our result, the relationship with the proximity to roads was a negative liner function, with the change rate decreasing rapidly when moving away from roads. Within a distance of less 7.5km from main traffic lines, land use changes occur red more. The bulk of grassland was apt to be opened up for cultivation around the settlements and the transformation from dryland to paddy occurred within the distance of 1km away from settlements.

关键词： land use change physical geographic region land use dynamic process effective coefficient cultural landscape variable

Climate change in the Sanjiang Plain disturbed by large-scale reclamation

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Journal of Geographical sciences 2002年第4期12卷 405-412页

作者： YAN Minhua, DENG Wei, CHEN Panqin(changchun institute of Geography, CAS, changchun 130021, china) changchun institute of Geography CAS Changchun China

Up to 1949, wetlands stretched continuously and accounted for 80.17% of the total area of plain part of the Sanjiang Plain. However, wetlands in the plain have gone through 4 periods (1956–1960, 1960–1977, 1980–1986, 1986-the present) of large-scale reclamation from 1956 to the present. Over 50% wetlands had changed into agricultural fields. The underlying surface of the plain has changed tremendously. This study investigated the regional climate change by analyzing regional climatic variation and tendency and examining climate jumps over the last 45 years. Monthly records of 5 climatic factors (air temperature, precipitation, atmospheric pressure, sunshine time and wind speed) for 26 meteorological stations covering the period 1955–1999 were used. The annual mean temperature of the study region was tending to go up and increased by 1.2–2.3 °C during the last 45 years. The maximum of annual precipitation decrease in the region was 90 mm over the last 45 years. An abrupt warming of the annual mean temperature occurred in the mid-1980s, which had an increase amplitude of 0.9 °C. Of increase amplitudes of all the seasonal abrupt warming, the largest one was 1.8 °C in the winter since 1987. The plain used to be cold and humid with center of Heilongjiang province even till the late 1960s, for it had an underlying surface of wetlands in the main. However, based on the facts of the climate changes of the plain over the last 45 years, it is held that the plain had a larger warming amplitude than that of area around it in recent years probably resulted from the large-scale reclamation of various kinds of wetlands.

关键词： climate change climate jump underlying surface the Sanjiang Plain large-scale reclamation

BRITTLE-DUCTILE TRANSITION OF POLYMERS AND ITS PERCOLATION MODEL

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Chinese Journal of Polymer science 2003年第2期21卷 129-134页

作者： Wei Jiang Li-jia An Bing-zheng Jiang State Key Laboratory of Polymer Physics and Chemistry changchun institute of Applied Chemistry Chinese Academy of sciences, changchun 130022, china Chinese Acad Sci Changchun Inst Appl Chem State Key Lab Polymer Phys & Chem Changchun 130022 Peoples R China

The brittle-ductile transition (BDT) of particlc toughened polymers was extensively studied in terms ofmorphology, strain rate, and temperature. The calculation results showed that both the critical interparticle distance (ID_c) andthe brittle-ductile transition temperature (T_(BD)) of polymers were a function of strain rate. The ID_c reduced nonlinearly withincreasing strain rate, whereas T_(BD) increased considerably with increasing strain rate. The effects of temperature andplasticizer concentration on BDT were discussed using a percolation model. The results were in agreement with theexperiments.

关键词： Particle toughening polymers Brittle-ductile transition Percolation

Present situation and tendency of saline-alkali soil in west jilin province

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Journal of Geographical sciences 2001年第3期11卷 321-328页

作者： LIU Hui-qing, XU Jia-wei, WU Xiu-qin (institute of Urban and Environment science, Northeast Normal University, changchun 130024, china) institute of Urban and Environment science Northeast Normal University

Taking west jilin province as an example, this paper put forward the assessment index of salinization, and based on it, the authors present the distribution characteristics of saline-alkali soil in the 1980s and the 1990s in west jilin and analyze its physical and chemical properties in detail. The developing tendency of salinization was also inferred by comparing the saline-alkali soil of the 1980s with that of the 1990s. Finally, the natural and human factors leading to salinization are analyzed.

关键词： saline-alkali soil west jilin salinization degraded soil

Research of Detecting Equipment Based on Grating Encoder of the Bogie Wheelset Alignment Parameters for Railway Vehicles

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Research of Detecting Equipment Based on Grating Encoder of ...