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A STUDY ON DESERTIFICATION OF WEST JILIN PROVINCE BASED ON REMOTE SENSING AND GIS TECHNIQUES

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Chinese Geographical Science 2002年第1期12卷 73-79页

作者： zhu jin hua, LI jin song(Changchun Institute of Geography, the Chinese Academy of Sciences, Changchun 130021, P.R. China) Changchun Institute of Geography the Chinese Academy of Sciences Changchun P. R. China

'West Jilin Province' in this paper means Zhenlai, Baicheng, Taonan, Da'an,Tongyu, Fuyu, Songyuan, Qian'an, Changling, also includes Gongzhuling, Shuangliao, Lishu, Siping andNong' an which have been suffered from desertification. In west Jilin Province there are three sandzones passing through, they are Xiang (Xianghai) -Wu (Ulan Tug) sand zone, Hai-Feng sand zone, andTao'er River right bank sand zone. The desertification area of west Jilin Province is 819 100 ha,making up 12. 5% of the total land area. Among desertification types, in Jilin Province lightdesertification is the major, then is medium decertification, hevey desertification is the *** to the comparison of the interpretation results of the Landsat images of the 1980s and the1990s by remote sensing and GIS techniques, it can be seen that the desertification area in westJilin Province basically didn't change on the whole, only increased 6130 ha, making up 0. 8% of thedesertification area, change scale is less than 1%. Evidently, desertification is controlled mostly,but some areas are continuing deterioration. The desertification process of China can be dividedinto three types according to origin nature, they are sandy steppe desertification, fixed sandarea(sand land) activation and dunes transfer invasion. Reasons of desertification of West JilinProvince are analyzed, they include natural factors (such as material source factors, chimatefactors) and artificial factors (such as destroying grass to reclaim, steppe decreasing greatly,illegally feeling shelter forest stands, constructing reservoir to influence eco-environment etc. ).Some suggestions are put forward as follows: establishing the social project for ecologicalreconstruction of degenerated land; intensifying planning and management of land use, revertingfarmland into forestland or pasture in a planned way. The key desertification control is to dependmainly on policy and management, then control techniques.

关键词： remote sensing (RS) and GIS techniques desertification west jilin province

The Effect of Electrochemical Polishing Time on Surface Topography of Mild Steel

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International Journal of Plant Engineering and Management 2006年第3期11卷 145-150页

作者： WANG Bao-cheng zhu jin-hua State Key Laboratory of Mechanical Behavior of Metal Material Xi＇an Jiaotong University Xi＇an 710049 P. R. China College of Material Science and Engineering Taiyuan University of TechnologyTaiyuan 030024 P.R. China

This paper investigated the variation of the altitude density function （ADF） and the autocorrelation function （ ACF） about the surface profile of mild steel during electrochemical polishing （ECP）. The results show that the variation features of ADF with polishing time are fiat-steep-fiat, and the variation features of A CF with polishing time are random-regular-random. There is a fine surface smoothness at the special period of ECP. Both the original surface and the full ECP surface show an obvious roughness.

关键词： mild steel electrochemical polishing altitude density function autocorrelation function

DESIGN AND COMPILATION OF AGRICULTURAL ELECTRONIC ATLAS AT COUNTY-LEVEL

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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

Local magnetic moment oscillation around an Anderson impurity on graphene

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 192-201页

作者： Shuai Li Zhen Ma jin-hua Gao School of Science Hebei University of Science and Technology School of Electronics and Information Zhengzhou University of Light Industry School of Physics and Wuhan National High Magnetic Field Center Huazhong University of Science and Technology

We theoretically investigate the spin resolved Friedel oscillation （FO） and quasiparticle interference （QPI） in graphene induced by an Anderson *** the impurity becomes magnetic,the resulted FO becomes spin dependent,which gives rise to a local magnetic moment oscillation with an envelop decaying as r-2in real space in the doping ***,at half filling,the electron density and local magnetic moment will not oscillate but decay as *** spin resolved FO has both sublattice and spin ***,the local magnetic moment decay at half filling only occurs at one sublattice of graphene,which is quite like the phenomenon observed in the STM experiment (***ález-Herrero et al.,Science 352,437 （2016）).We further give an analytic formula about such spin dependent FO based on the stationary phase ***,we study the interference of quasiparticles around the magnetic impurity by calculating the spin dependent Fourier-transformed local density of states （FT-LDOS）.Our work gives a comprehensive understanding about the local magnetic moment oscillation around an Anderson impurity on graphene.

关键词： Friedel oscillation local magnetic moment graphene Anderson impurity

Banach空间有限簇变分包含组的解与有限簇λ-严格伪压缩映象的不动点的逼近

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数学的实践与认识 2013年第19期43卷 207-217页

作者：朱浸华宜宾学院数学研究所四川宜宾644000

介绍了一种新的迭代方法,在Banach空间的框架下,用以寻求一族关于逆强增生算子的变分包含组的解集与有限簇λ-严格伪压缩映象的不动点集的公共元.在适当条件下,逼近于这一公共元的强收敛定理被证明.介绍的结果是新的,它改进和推广了一... 详细信息

介绍了一种新的迭代方法,在Banach空间的框架下,用以寻求一族关于逆强增生算子的变分包含组的解集与有限簇λ-严格伪压缩映象的不动点集的公共元.在适当条件下,逼近于这一公共元的强收敛定理被证明.介绍的结果是新的,它改进和推广了一些人的最新结果.

关键词：变分包含组变分不等式不动点 λ-严格伪压缩映象强收敛

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19世纪晚期中西欧“谷物大入侵”探析

中国农史 2021年第4期40卷 20-31页

作者：朱华进广西民族大学民族学与社会学学院广西南宁530006

19世纪晚期中西欧“谷物大入侵”是指19世纪70年代初至90年代中叶,中西欧诸多国家面临来自美俄等世界农业生产大国的谷物持续性大规模涌入的现象,这一现象深刻影响了中西欧农业发展的进程。“谷物大入侵”打破了中西欧农业生产与贸易的... 详细信息

19世纪晚期中西欧“谷物大入侵”是指19世纪70年代初至90年代中叶,中西欧诸多国家面临来自美俄等世界农业生产大国的谷物持续性大规模涌入的现象,这一现象深刻影响了中西欧农业发展的进程。“谷物大入侵”打破了中西欧农业生产与贸易的平衡状态,主要农产品的价格持续下跌,土地价格与租金等亦有不同幅度的下滑,直至19世纪90年代中叶外部谷物输入的衰退才使得这场农业慢性萧条宣告结束。“谷物大入侵”是世界农业大国农业生产大发展、交通运输革命、欧洲贸易壁垒瓦解等因素综合作用的产物,它催化中西欧国家的农业启动变革,包括加速农业迈向专业化与现代化、促使经济作物和食品加工业成为新发展方向、提高传统农业的生产效率等。但整体而言,在主要大国农业保护的姿态下,“谷物大入侵”仅是有限地影响中西欧农业革命的演进。

关键词： “谷物大入侵” 19世纪晚期小麦农业革命中西欧

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混合平衡问题组及不动点问题公解的算法

四川师范大学学报（自然科学版） 2012年第5期35卷 656-662页

作者：朱浸华宜宾学院数学系四川宜宾644007

最近,文献(***.,2008,214:186-201.)讨论了关于有限个非扩张映象的解集与一个混合平衡问题的不动点集的公共元的迭代序列.受他们的启发,介绍了一种新的迭代算法,在Hilbert空间的框架下,用以寻求混合平衡问题组的解集与无限族的非扩张映... 详细信息

最近,文献(***.,2008,214:186-201.)讨论了关于有限个非扩张映象的解集与一个混合平衡问题的不动点集的公共元的迭代序列.受他们的启发,介绍了一种新的迭代算法,在Hilbert空间的框架下,用以寻求混合平衡问题组的解集与无限族的非扩张映象的不动点集的公共元.在适当条件下,逼近于这一公共元的强收敛定理被证明.所得结果是新的,它改进和推广了最近一些人的最新结果.

关键词：混合平衡问题不动点无限族的非扩张映象 η-强凸函数