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Ecological rebuilding and land reclamation in surface mines in Shanxi Province, China

Journal of Environmental Sciences 2000年第4期12卷 486-497页

作者： MIAO Ze wei 1. BAI Zhong ke 2, gao Lin 1.(1. Research Center for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 1.0085, China E\|mail: miaozewei@*** 2. Department of Soil Science, Shanxi Agricultural University Taigu, 03 中科院生态环境研究中心北京 1 0 0 0 85 山西师范大学山西临汾 0 3 0 80 1

It is well known that the mining industry produces a large amount of derelict land, and causes pollution of water loss and soil erosion as well as other environmental damage in China. As land is under pressure in China, it is now policy to restore or reclaim land despoiled by mining, the aim being to develop sustainable and healthy arable land ecosystems. This paper outlines the principles and approaches of ecological restoration, which have been adopted in Shanxi Province with reference to three typical surface mines. In the research, the principles of ecological engineering and ecological succession are considered as the critical theories of ecological restoration in mine degraded land. Meanwhile, the paper made a comparative research on main links of ecological rebuilding in three surface mines in Shanxi Province, which include new land construction, treatment of toxic substances, control of soil erosion, fertility management, irrigation, ecological planning and the establishment of legislation systems. As the research demonstrated, for successful restoration, new land construction is the fundamental framework, but it must be integrated with ecological engineering including ecological planning, the control of soil erosion and vegetation establishment and ecosystem creation in order to optimise land productivity and soil fertility. In addition, the establishment of the legislation systems and organization of administration are also indispensable aspects of ecological rebuilding in mined land.

关键词： ecological restoration land reclamation open-pit mine

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Dynamic Properties of Concrete under Severe Environmental Condition

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Journal of Wuhan University of Technology(Materials Science) 2010年第5期25卷 877-882页

作者：闫东明 Department of Hydraulic and Environmental Engineering Zhengzhou University Department of Civil and Hydraulic Engineering Dalian University of Technology

Exposure to environmental conditions can significantly influence the mechanical behavior of concrete structures in civil engineering. In this study, the effect of environmental factors, such as moisture and temperature, on the strain-rate sensitivity of concrete mixtures was systematically investigated. The strain rate varied from 1.^-5s^-1.to 1.^-2s^-1. From the investigation it was concluded that moisture content had a significant influence on the strain-rate sensitivity of concrete. With regard to concrete with low moisture content, temperature had little influence on the rate-dependent behavior; while for fully saturated specimens, a significant influence was observed. These phenomena were attributed to the meso-scale bonding properties of the concrete matrix. Equations were derived to characterize the ultimate strength increment of concrete with strain rate under different environmental conditions. An explanation to the dynamic failure mechanisms of concrete based on the experimental findings was proposed.

关键词： concrete strain rate moisture content temperature failure mechanism

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Stabilization Of Nonlinear Hybrid Systems

Stabilization Of Nonlinear Hybrid Systems

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第二十四届中国控制会议

作者： Haijun Liu~1. Xiaowu Mu~1. Yongliang gao~2 (1. University of Zhengzhou, Zhengzhou, 450052)

＜正＞ In this paper we consider general nonlinear hybrid systems. Under an additional assumption, we prove that there exists a switching rule depending on state space which stabilizes the system in a very general sen... 详细信息

关键词： stabilization hybrid systems nonlinear systems krasowski solutions Lyapunov function

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A simulation analysis on pelagic-benthic coupling ecosystem of the northern Jiaozhou Bay, Qingdao, China

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Acta Oceanologica Sinica 2001年第3期20卷 443-453页

作者： Wu Zengmao, Zhai Xuemei, Zhang Zhinan, Yu Guangyao, Zhang Xinling, gao Shanhong 1. College of Physical and Environmental Oceanography, Ocean University of Qingdao, Qingdao 266003, China 2. College of Marine Biology Science, Ocean University of Qi Coll. Physical/Envrn. Oceanography Ocean University of Qingdao Qingdao 266003 China College of Marine Biology Science Ocean University of Qingdao Qingdao 266003 China

INTRODUCTIONWith the development of economy and the exploitation of coastal resources, the coastal en vironment of the northern part of China was seriously damaged, especially in the Jiaozhou *** attention was paid to... 详细信息

关键词： Ecosystem model the Jiaozhou Hay pelagic-benthic coupling ecosystem seasonal variation simulation

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地下结构抗震动力可靠度分析

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铁道学报 2004年第5期26卷 96-100页

作者：严松宏高峰高波兰州交通大学土木工程学院甘肃兰州730070 西南交通大学土木工程学院四川成都610031

由于地震的随机性,开展地下结构随机地震响应及其抗震可靠度分析具有重要的实际意义。本文从有限元动力分析的基本原理出发,利用脉冲响应函数和傅立叶变换原理,研究了将地震荷载作为平稳随机过程时地下结构随机地震响应分析方法,导出了... 详细信息

由于地震的随机性,开展地下结构随机地震响应及其抗震可靠度分析具有重要的实际意义。本文从有限元动力分析的基本原理出发,利用脉冲响应函数和傅立叶变换原理,研究了将地震荷载作为平稳随机过程时地下结构随机地震响应分析方法,导出了平稳随机地震作用下地下结构动力响应的数字特征计算表达式。分析了地下结构在某烈度地震作用下和设计基准期内的抗震可靠度。

关键词：地下结构随机地震响应脉冲函数傅立叶变换抗震可靠度

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The (mod,integral) Sum Numbers of Fans and Kn,n-E(nK2)

The (mod,integral) Sum Numbers of Fans and Kn,n-E(nK2)

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2006年中国运筹学会数学规划分会代表会议暨第六届学术会议

作者： Wenqing Dou1. 2 Jingzhen gao 2 (1. Department of Mathematics, zhejiang University 2. Department of Mathematics, Shandong Normal University)

Let N ( Z ) denote the set of all positive integers (integers). The sum graph G + ( S) of a finite subset S N ( Z) is the graph ( S , E ) with uv ∈ E if and only if u + v ∈ S. A graph G is said to be

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Partial melting and re-solidification in partially melted zone during gas tungsten arc welding of AZ91.cast alloy

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Transactions of Nonferrous Metals Society of China 2007年第S1期 342-346页

作者： T. P. ZHU1.Z. W. CHEN2,W. gao1.1. Department of Chemical and Materials Engineering,University of Auckland,NZ 2. Department of Mechanical and Production Engineering,Auckland University of Technology,New Zealand

During the welding of AZ91.cast alloy,the presence of eutectic β-Mg1.Al1. phase results in constitutional liquation in the original interdendritic regions and in the formation of a partially melted zone(PMZ). In this study,gas tungsten arc welding(GTAW) and partial melting(simulated using furnace,salt bath and Gleeble) experiments were conducted. The results show that practically there would not be a critical heating rate during the welding to prevent constitutional liquation. The gradual change of the re-solidification microstructure within PMZ from base metal side to weld metal side was characterized. A sharp transition from base metal to PMZ has been observed. It is found that the original partially divorced eutectic has become a more regular eutectic in most of the PMZ,although close to the fusion boundary the re-solidified eutectic is again a more divorced one. Proceeding the eutectic re-solidification,α-Mg re-solidified with a cellular growth resulting in a serrated interface. The morphological change affected by the peak temperature and cooling rate will be presented and explained.

关键词： Mg cast alloy partial melting divorced and regular eutectic solidification

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集中化调车作业研究

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铁道学报 2004年第6期26卷 8-13页

作者：高四维高雅西南交通大学峨眉校区交通运输系四川峨眉614202 西南交通大学计算机与通信工程学院四川成都610031

在分析自动化指挥系统与作业组织方式相互关系的基础上,以提高整体调车效率为目标,提出集中运用调车设备、进行整批次高深度选编、使多元性选编目标综合达成的集中化调车作业新模式;在研究集中化调车作业与分散化调车作业取向差异的基础... 详细信息

在分析自动化指挥系统与作业组织方式相互关系的基础上,以提高整体调车效率为目标,提出集中运用调车设备、进行整批次高深度选编、使多元性选编目标综合达成的集中化调车作业新模式;在研究集中化调车作业与分散化调车作业取向差异的基础上,明确了集中化调车作业的采用条件,指出盲目分散化作业的主要表现;论证集中化选编模型的有效性及推行集中化调车作业的必要性;在实现自动化指挥的条件下,就如何采用集中化作业组织方式提出了具体建议。

关键词：调车作业优化集中化选编模型集中化作业组织方式自动化指挥系统

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The temperature system identification of the PVC stripper tower top based on PSO-FCM optimized T-S model

The temperature system identification of the PVC stripper to...

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第24届中国控制与决策会议

作者： gao Shuzhi 1., Dou Xing 1., gao Xianwen 2 1. College of Information Engineering, Shenyang University of Chemical Technology, Shenyang 1.01.2, China2. College of Information Science and Engineering, Northeastern University, Shenyang 1.01.9, China

In view of the characteristics of T-S model, such as easily expressing complex dynamic systems and the characteristics of PSO algorithm which could find the optimal solution of complex problems easily. This paper will presents a new identification method based on the T-S model in which FCM parameters is optimized by *** mathematical model of the temperature system of the PVC stripper tower top will be built by this method . First, an adaptive number of clusters of C-means clustering fuzzy (FCM) algorithm is used to find the appropriate number of clusters in FCM, and both the number of fuzzy rules and the premise parameters of the model can are determined. Using PSO algorithm to optimize the FCM algorithm, then getting the best membership matrix by the FCM algorithm based on PSO in the ***,a least square algorithm is applied to determine the parameters of consequent part of T-S model. The simulation result shows the effectiveness and feasibility of the modeling method..

关键词： T-S model fuzzy c-means clustering (FCM) least squares algorithm polyvinyl chloride (PVC) Particle swarm optimization algorithm PSO)

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Superconductivity in MgB2

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Progress in Natural Science:Materials International 2002年第11期 3-9页

作者： DAI Wen, FENG Qingrong and gao Zhengxiang(1. Cryogenic Laboratory, Chinese Academy of Sciences, Beijing 1.0080, China 2. Department of Physics, Peking University, Beijing 1.0871. China) Cryogenic Laboratory Chinese Academy of Sciences Beijing 100080 China Department of Physics Peking University Beijing 100871 China

In January of 2001.the superconductivity of the compound MgB2 with a critical temperature Tc of up to 39 K was discovered. This Te is the highest in all intermetallic compound and alloy superconductors. MgB2 has a simple structure and its manufacturing capital cost is lower, therefore it could become a practical superconductor in the future. The recent progress is reviewed here which covers the progress in electronic structure, high 7% mechanism, superconducting parameters (Debye temperature, specific heat coefficient of electron, critical fields, coherent length, penetration depth, energy gap, critical current and relaxation rate of flux). Moreover the issue on power transmission is discussed.

关键词： MgB2 superconductivity electronic structure critical parameters electric transmission.

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