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Does the F10.7 index correctly describe solar EUV flux during the deep solar minimum of 2.07-2.09?

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Does the F10.7 index correctly describe solar EUV flux durin...

OPTIMIZATION　OF　ACOUSTIC　IMPEDANCE，GEOMETRIC　STRUCTURE　AND　OPERATING　CONDITION　OF　LINERS　MOUNTED　IN　ENGINE　DUCT

中国科学院地质与地球物理研究所第11届（2.11年度）学术年会

作者： Yiding Chen,Libo Liu,and Weixing Wan 1 beijing National Observatory of Space Environment,Institute of Geology and Geophysics,chinese{2. of sciences,beijing,China. 2.State Key Laboratory of Space Weather,Center for Space Science and Applied Research,chinese{2. of sciences,beijing,China.

[1]This paper shows that the relationship between solar EUV flux and the F index during the extended solar minimum(Smin) of 2.07-2.09 is different from that in the previous *** difference is also seen in the relationship between fF and *** collected SOHO/SEM EUV observations and the F index,through June 2.10,to investigate solar irradiance in the recent *** find that,owing to F and solar EUV flux decreased from the last Smin to the recent one with different amplitudes(larger in EUV flux),EUV flux is significantly lower in the recent Smin than in the last one for the same ***,F does not describe solar EUV irradiance in the recent Smin as it did in the last *** caused remarkable responses in ionospheric fF,For the same F,fF in the recent Smin is lower than that in the last one;further,it is also lower than that in other previous ***,F is not an ideal indicator of fF during the recent Smin,which implies that F is not an ideal proxy for solar EUV irradiance during this period,although it has been adequate during previous *** irradiance models and ionospheric models will need to take this into account for solar cycle investigations.

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chinese Journal of Aeronautics 1996年第3期9卷 193-203页

作者： Lu Yadong Wang Qingkuan(Institute of Engineering Thermophysics, chinese academy of{2., beijing, China, 100080).Hu Zongan Cul Jiya (Beijig University of Aeronautics and Astronautics, beijing, China, 100083) Inst. of Engineering Thermophysics Chinese Academy of Sciences Beijing 100080 China Beijng Univ. of Aero. and Astronaut. Beijng 100083 China

Acoustically absorptive treatment in aircraft engine nacelle is an essential part of the overall aircraft noise reduction effort. The investigation on the optimization of multi-liners plays an important role in noise reduction. Based upon the mode analysis method of sound propagation in a circular duct with multiple liners, a flexible tolerance method is used to optimize the acoustic parameters(impedance), geometric structure parameters(such as open area ratio, cavity depth and hole diameter) and operating condition parameters(such as blade passing frequency). The mathematical models for these kinds of optimization are presented here. The optimum values of the design variables are determined when the in-duct sound suppression approaches a maximum. It can be derived from the optimum results that the emphasis of the engineering optimization design of the perforated plate honey-comb structure should be placed on the optimum choice of the open area ratio and cavity depth. Some reference criteria for the engineering design of the multi-linings are also provided.

关键词： engine inlets ducts linings aeroacoustics. acoustic impedance,Optimization

Functional evolutionary developmental biology (evo-devo) of morphological novelties in plants

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Journal of Systematics and Evolution 2010年第2期48卷 94-101页

作者： Jisi ZHANG Ying TIAN Li WANG Chaoying HE (State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of{2.,beijing 100093,China) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) *Correspondence: Chaoying HE *Correspondence: *?Author for correspondence. E-mail: chaoying@*** Tel.: 86-10-62.3-6085 Fax: 86-10-62.9-0843.

The origin of morphological and ecological novelties is a long-standing problem in evolutionary *** these processes requires investigation from both the development and evolution standpoints,which promotes a new research field called "evolutionary developmental biology" (evo-devo).The fundamental mechanism for the origin of a novel structure may involve heterotopy,heterochrony,ectopic expression,or loss of an existing regulatory ***,the morphological and ecological traits controlled by the regulatory genes may be gained,lost,or regained during *** morphological novelties,for example,include homeotic alterations (related to organ identity),symmetric diversity,and changes in the size and morphology of the floral *** gains and losses can potentially arise through modification of the existing regulatory ***,we review current knowledge concerning the origin of novel floral structures,such as "evolutionary homeotic mutated flowers",floral symmetry in various plant species,and inflated calyx syndrome (ICS) within *** evo-devo of the morphological novelties is a central theme of plant evolutionary *** addition,the discussion is extended to consider agronomic or domestication-related traits,including the type,size,and morphology of fruits (berries),within Solanaceae.

关键词： biodiversity development evolution functional evo-devo heterochrony heterotopy morphological novelty

Impacts of Yulong Mountain Glacier on Tourism in Lijiang

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Journal of Mountain Science 2006年第1期3卷 71-80页

作者： YUAN Lingling LU Aigang NING Baoying HE Yuanqing Cold and Arid Regions Environmental and Engineering Institute Chinese Academy of Sciences Lanzhou 730000 China The Institute of Tibet Research Chinese Academy of Sciences Beijing 100029 China

The glacier on the Yulong Mountain is one of the most important attractions in Lijiang, Yunnan, China. But it keeps retreating these years due to global warming, which is bound to influence regional tourism significantly in Lijiang. This study estimates the effects of the glacier retreat of the Yulong Mountains on tourism there. Primary data were collected through a visitor survey including demographics, motives, lengths of stay, and opinions about each tourism resource from tourists to Lijiang, as well as questions about which scenic spot（s） they had visited or would visit, how much they expended per day during their visit and how their visiting behavior would be changed upon the hypothesis that the glacier would disappear. These data were used to analyze the proportion of the contribution of glacier to the tourism in Lijiang and estimate the impact of glacier on the regional tourism quantitatively. According to the survey, it could be concluded that three quarters of the tourists to Lijiang were interested in the Yulong Mountain glacier, indicating that the glacier possesses notable appeal for sightseeing tourists. The results of our analysis showed that about 689,013-1,508,2.7 tourists, accounting for 19.63-42.97 % of the total 3,510,000 domestic tourists to Lijiang in 2.04, would not come to Lijiang in the absence of the glacier, resulting in a possible direct economic loss of 84,382.508-184,713,011 USD （viz. 700,374,82.-1,533,117,993 RMB） and a markedly decrease in the attraction radius.

关键词： Glacier retreat tourism economic impact appraisal Lijiang Yulong Mountain China

The basic theories of traffic economic belt (TEB)and its life-circle pattern

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Journal of Geographical sciences 1999年第4期9卷 415-420页

作者： YANG Yin-kai HAN Zeng-lin ZHANG HOng-li(Institute of Geography, chinese academy of{2., beijing 100101)(Department ofGeography, Liaoning Normal University, Dalian 11602.)

With the development of productive forces. the space evolution of regional economicSystem keeps closer links with the traffic transport line. A kind of linear space regional scathetic bodyforms constantly and develops rapidly. Relying on the traffic trunk lines, it aggregates and *** the same time, it mixes population, industry, town, interflow of commodities, interflowof energy and interflow of information *** unique space regional synthetic body is calledtraffic economic belt (TEB). In the paper, the basic concepts, types and qualities of TEB wereelaborated and the life-circle theory was put forward creatively.

关键词： traffic economic belt (us), time and space evoluhon liferoircle

COLD WINTER EVENTS RECORDED IN HISTORICAL DOCUMENTS OF THE TROPICAL AREA, CHINA

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Scientia Geologica Sinica 2001年第3期 205-210页

作者： Rui Chen, Guoqiang Chu and Jiaqi Liu Institute of Geology and Geophysics, chinese academy of{2., beijing 10002.

Historical documents to record cold winter events of the tropical area, such as snowfall, freeze and frost, are convincible evidence of the Little Ice Age (LIA). Cold winter events recorded in historical documents such as local chronicles of areas (tropical areas) to the south of the Tropical of Cancer, China provide such evidence. The statistic data of the past several centuries, such as the year number of cold winter per decade, the index of cold winter and the number of county with cold winter records per decade suggest that the colder winter in the tropical areas of China was concentrated in four periods: 1380-1430 A D, 1480-1550 A D, 162.-1770 A D and 1830-1900 A D. The LIA influenced the climate of the tropical areas of China. However, temperature of the LIA was not lower always, but there was a series of alternative warm and cold times.

关键词： CHINA COLD WINTER EVENTS RECORDED IN HISTORICAL DOCUMENTS OF THE TROPICAL AREA LIA WCRP

Design and realization of web based principal function area division auxiliary system

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基于SSM的伊犁河流域主导产业选择定量化研究

2.10 Third Pacific-Asia Conference on Web Mining and Web-based Application (WMWA 2.10)

作者： Wen Dong Institute of Remote Sensing Applications chinese academy of{2. beijing China Xin Zhang Institute of Remote Sensing Applications chinese academy of{2. beijing China

We have done a lot of research works on principal function area division evaluation method,technology and processing after government clearly announced to promote main function region formation and work out some ***,the principal function area division is a new theory and method with chinese characteristics of zoning planning,and there aren’t enough international results and *** a result,there are a lot of problems in ours works,such as data sharing,interaction between departments,public participation and so *** solve these problems,this article proposes a SOA based principal function area division auxiliary system framework to realize data sharing and multidepartment collaboration on *** article designs a three layer system framework base on web services,and discusses the function structure of *** on the discussion,we use Hebei province as a test zone to do application experiment of this ***,we discuss the meaning of system building and system application envision.

关键词： SOA principal function area division web application system framework design web services

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山地学报 2010年第2期28卷 199-205页

作者：陈忠升陈亚宁李卫红陈亚鹏中国科学院新疆生态与地理研究所/中国科学院绿洲生态与荒漠环境重点实验室中国科学院研究生院

在梳理了传统主导产业选择基准理论与偏离-份额分析法基本原理的基础上,选取伊犁河流域1997年和2.06年两个时间点的30个工业部门为分析对象,以国家范围内的30个工业部门的情况为参照,对研究区30个工业部门进行了份额偏离分量、结构偏离... 详细信息

在梳理了传统主导产业选择基准理论与偏离-份额分析法基本原理的基础上,选取伊犁河流域1997年和2.06年两个时间点的30个工业部门为分析对象,以国家范围内的30个工业部门的情况为参照,对研究区30个工业部门进行了份额偏离分量、结构偏离分量和竞争力偏离分量的综合比较分析。结果表明,农副食品加工业、纺织业以及电力、热力的生产和供应业3个产业部门最有可能成为主导产业;同时,也说明研究方法具有基本客观性、有效性和较强的操作性。

关键词：偏离-份额分析法伊犁河流域主导产业选择

Development of Rapidly Quenched Soft Magnetic Materials in China

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Journal of Materials Science & Technology 2000年第2期16卷 131-136页

作者： Shaoxiong ZHOU (National Amorphous and Nanocrystalline Alloy Engineering Research Center, Central Iron and Steel Research Institute, beijing 100081, China) National Amorphous and Nanocrystalline Alloy Engineering Research Center Central Iron and Steel Research Institute Beijing 100081 China

The discovery of the first Fe-based ferromagnetic amorphous alloy in 1966 had made an impact on conventional magnetic materials because of its unique properties. Since then, a number of amorphous magnetic materials have been successfully developed and used in a wide variety of applications. A brief review of R & D activities on amorphous soft magnetic materials in China is given from the beginning to the present in a somewhat chronological order, followed by a brief introduction to their applications on electric and electronic industries. An analysis and a prospect of chinese market of such amorphous materials are also presented.

关键词： Development of Rapidly Quenched Soft Magnetic Materials in China