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基于RBF神经网络的交叉检验图像降噪方法

计算机科学 2004年第12期31卷 151-153页

作者：李宏寨郭平北京师范大学信息学院计算机系北京100875

径向基神经网络(RBFNN)有很好的函数逼近能力,本文把图像看成函数,用RBFNN来表示图像,并在学习过程中进行逼近,采用交叉检验的方法来确定网络模型并控制学习过程,使得网络既能较好地逼近图像,又对噪声进行抑制,从而达到图像降噪的目的... 详细信息

径向基神经网络(RBFNN)有很好的函数逼近能力,本文把图像看成函数,用RBFNN来表示图像,并在学习过程中进行逼近,采用交叉检验的方法来确定网络模型并控制学习过程,使得网络既能较好地逼近图像,又对噪声进行抑制,从而达到图像降噪的目的。实验证明这是一个可行的盲目图像降噪方法,有广泛的适用性。本文还给出了实验中改进交叉检验方法的技术,给出了与wiener滤波器降噪的实验效果对比图。

关键词：函数逼近能力图像降噪 RBF神经网络交叉径向基神经网络表示网络模型 wiener滤波器噪声抑制

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黎曼流形上混合边值问题的第一特征值估计

数学学报（中文版） 2003年第5期46卷 843-850页

作者：杨洪苍中国科学院数学与系统科学研究院数学研究所

设M为一带边界M的紧致Riemann流形,本文考虑M上的下述混合边值条件的特征值问题 (△u+v_1u=0, u/n+αu|M=0,)其中n为M的外法向单位向量,α为一正常数。

关键词：特征值黎曼流形混合边值条件

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 Sciences, beijing 100101)(Department ofGeography, Liaoning normal university, Dalian 116029)

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

GROWTH AND PROPERTIES OF FeSi2 BY MEVVA IMPLANTATION AND RTA

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GROWTH AND PROPERTIES OF FeSi2 BY MEVVA IMPLANTATION AND RTA

1995 4th International Conference on Solid-State and Integrated Circuit Technology

作者： Weidong Qian Tonghe Zhang hong LiangRadiation Beam & Material Engineering Lab. Institute of Low Energy Nuclear Physcics beijing normal university china 100875

＜正＞ The Fe silicides were fabricated using MEVVA Fe ion implantation into P-Si with different ion flux Φ. The relation of sheet resistance R□with annealing temperature Ta was obtained usingfour-point probe. It was found that R□decreased rapidly with increasing Φand Ta. XRD analysis shew that the semiconductor phase β- FeSi, was formed for as-implanted sample and post annealed sample with the temperature from 800℃to 1000℃. It was proved that there was a phase transition from β- FeSi2 （semiconducting ） to α- FeSi2 （metallic） after the samples were annealed at 1100℃for 10s.

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校长专业化的知识基础

教育理论与实践 2003年第12期23卷 27-32页

作者：褚宏启北京师范大学教育管理学院北京100875

没有稳固的知识基础,校长专业化是不能实现的。校长专业化所需要的知识应符合效用、数量和质量标准,做到有用、够用、好用。校长专业化的知识基础应由实践性知识构成,应把实践性知识从已有的数量庞大的教育管理知识中剥离出来,并依据质... 详细信息

没有稳固的知识基础,校长专业化是不能实现的。校长专业化所需要的知识应符合效用、数量和质量标准,做到有用、够用、好用。校长专业化的知识基础应由实践性知识构成,应把实践性知识从已有的数量庞大的教育管理知识中剥离出来,并依据质量标准对其加工整合。建构校长专业化的知识基础,除了利用已有知识,还需要生产新的实践性知识。在此过程中,研究者应深入实践,实践者应反思实践并成为新知识的生产者。

关键词：校长职业专业化知识基础

Ten key issues for ecological restoration of territorial space

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National Science Review 2024年第7期11卷 75-79页

作者： Jian Peng Dongmei Xu Zihan Xu Hui Tang hong Jiang Jianquan Dong Yanxu Liu Technology Innovation Center for Integrated Ecosystem Restoration and Sustainable Utilization Ministry of Natural Resources College of Urban and Environmental Sciences Peking University School of Soil and Water Conservation Beijing Forestry University Key Laboratory for Environmental and Urban Sciences School of Urban Planning and DesignShenzhen Graduate School Peking University School of Landscape Architecture Beijing Forestry University State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical Science Beijing Normal University

Ecological restoration is an effective measure to protect biodiversity, sustain ecosystem services and enhance socialecological resilience. It is defined as the process of assisting the recovery of an ecosystem that h... 详细信息

关键词： PRIORITY AREAS

Estimation of suspended sediment concentration based on bio-optical mechanism and HJ-1 image in Chaohu Lake

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Science china Earth Sciences 2010年第S1期53卷 58-66页

作者： WANG Qiao1,2,JIN Xin2,LI YunMei2,WU ChuanQing1,Lü Heng2,WANG YanFei2,ZHANG hong2,YIN Bin2 & ZHU Li1 1Satellite Environment Center,Ministry of Environmental Protection,beijing 100029,china 2Key Laboratory of Virtual Geographic Environment of Education Ministry,Nanjing normal university,Nanjing 210046,china Satellite Environment Center Ministry of Environmental Protection Beijing China Key Laboratory of Virtual Geographic Environment of Education Ministry Nanjing Normal University Nanjing China

Synchronization experiment was conducted in June,2009 to get Inherent Optical Properties(IOP) of water component in Chaohu *** bio-optical mechanism was studied combined with multispectral data of Environmental Satellite 1(CCD),and then inversion models of total suspended matter(TSM),inorganic suspended matter(ISM) and organic suspended matter(OSM) concentration were *** data indicated that:the absorption ratio of suspended particulate matter and CDOM to total were almost no change from band 1 to band 2 with about 85% and 9%,*** ratio of pure water to total increased from 0.4% to 5.6%.Water reflectance in these two bands were influenced by absorption of three kinds of components:algae particles absorption surpassed non-algal particles in band 3,and so played an important role in total absorption with about 35.7%;the proportion of pure water absorption and particles matter backscattering both were 99% in band 4,so these two components decided the main inherent optical properties in band *** models of TSM and ISM concentration inversion based on band combination(band 3 + band 4)/(band 1 + band 2) were built,while OSM concentration was estimated by band 4/(band 1 + band 2) *** by image data,RE of TSM concentration between modeled and measured was 33.4%,and RMSE was 18.68 mg/*** of ISM and OSM concentration were 39.9% and 35.2% *** inversion was more accurate when satellite-ground data were just in the same *** this situation,RE of ISM concentration dropped to 25.4%,and that of TSM and OSM reduced to 26.5% and 26.8% as well.

关键词： HJ-1 Satellite bio-optical property Chaohu Lake suspended matter

Study of Petroleum Hydrocarbons under Chemical-biological Degradation in Contaminated Soils

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Study of Petroleum Hydrocarbons under Chemical-biological De...

2009 International Conference on Environmental Science and Information Application Technology

作者： Ningning Sun hongqi Wang Jingqi Liu Yongqiang Qi College of Water Sciences beijing normal university beijing china

Microbial decontamination of petroleum-polluted soils has been recognized to be an efficient,economical and versatile alternative for physical or chemical *** this study,different components of petroleum in contaminated soil were investigated under optimal environmental conditions which were determined by previous *** aerobic bacteria with the ability to utilize both hydrocarbons and benzene as carbon sources was identified as Flavobacterium *** on morphological,physiological and biochemical *** results demonstrate a 39.88%removal rate for total petroleum hydrocarbons over a period of 27 *** fractions of the petroleum were observed to be degraded *** degradation rate declines with increasing alkane chain length （carbon number）.It was found that the total degradation rate can be approximated by the degradation rate of the n-alkane with 23 carbon atoms.N-alkanes with carbon number lower than 23 were removed faster than the total hydrocarbon amount,and the reverse trend was observed for n-alkanes with carbon number higher than *** n-alkanes,the degradation rate of total iso-alkanes can be simulated by that of with iso-alkanes with 19 carbon *** benzene utilization studies with the bacteria species showed that it metabolizes benzene when benzene concentration is under 10 mg/L,concentrations over which turn out to be *** optimal conditions for effective removal of benzene by this species appear to be 30oC,pH of 6.5-6.7,inoculum concentration of 10%（v/v）.

关键词： total petroleum hydrocarbons n-alkanes iso alkanes microorganism benzene degradation

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球孢白僵菌毒素的分离、毒力检测及结构鉴定

微生物学报 1998年第6期38卷 468-474页

作者：武艺黄秀梨洪泂邓继先北京师范大学生物系北京100875 军事医学科学院生物工程研究所北京100071

用吸附法从球孢白僵菌（Ｂｅａｕｖｅｒｉａｂａｓｓｉａｎａ）１００３－Ｖ的代谢产物中分离出导致昆虫患病的毒素粗提物，并对其进行了毒力检测。结果表明，该毒素对白纹伊蚊（Ａｅｄｅｓａｌｂｏｐｉｃｔｕｓ）幼虫有明显毒性；对棉... 详细信息

用吸附法从球孢白僵菌（Ｂｅａｕｖｅｒｉａｂａｓｓｉａｎａ）１００３－Ｖ的代谢产物中分离出导致昆虫患病的毒素粗提物，并对其进行了毒力检测。结果表明，该毒素对白纹伊蚊（Ａｅｄｅｓａｌｂｏｐｉｃｔｕｓ）幼虫有明显毒性；对棉铃虫幼虫口服毒性较弱。

关键词：球孢白僵菌毒素棉铃虫白纹伊蚊毒力检测