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Categories and characteristics of urban villages by GIS-based analysis:A case study of the Shenzhen Special Economic Zone

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Science China(Technological Sciences) 2010年第S1期53卷 150-157页

作者： TONG De1,FENG ChangChun2,LI GuiCai1 & CHEN Peng1,2 1S henzhen Graduate School,Peking University,Shenzhen 518055,China 2College of Urban and Environmental Science,Peking University,Beijing 100871,China Shenzhen Graduate School Peking University Shenzhen China College of Urban and Environmental Science Peking University Beijing China

Studies on the characteristics of urban villages have attracted much interest in urban geography.However,how to advance the development of further theoretical analysis and quantitative methodologies,especially in the era that GIS and digital-urban technologies develop rapidly and provide precious resources on spatial issues,has always been a heated debate and difficulty.In this paper,a mathematical model based on spatial analysis is introduced to deal with the categorization and characterization of urban villages.A total of 89 urban villages in the Shenzhen Special Economic Zone(SEZ)are used in this case study.Using ArcGIS tools on buffer analysis,distance and density calculation,and socio-economic and spatial attributes conjunction,urban villages’31 spatial variables in 4 aspects—social,economic,locational,and physical—are extracted,and 6 principal factors are concluded by principal components analysis to indicate the spatial characteristic of urban villages.Based on the 6 principal factors,6 types of urban villages,including rapidly sprawling,large,rapidly industrializing periphery,overcrowded,intensively mobile and economically backward,are divided through the Hierarchical Clustering method.Moreover,the spatial features and formation mechanisms of each type of urban villages are provided.Finally,the advantages and the shortcomings of the methodology for this specific application are also given.Furthermore,several guidelines on urban village management and renewal are provided based on the result of type classification.The outcome of the paper depends on the informational and technological support from the development of digital-city management,and is able to in turn provide basis on monitoring and improving urban villages which can further digital urban framework.

关键词： urban villages GIS-based analysis principal component hierarchical cluster the Shenzhen Special Economic Zone (SEZ)

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Aerodynamic optimization of rotor airfoil based on multi-layer hierarchical constraint method

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Chinese Journal of Aeronautics 2016年第6期29卷 1541-1552页

作者： Zhao Ke Gao Zhenghong Huang Jiangtao Li Quan The First Aircraft Institute of AVIC Xi’an 710089China National Key Laboratory of Aerodynamic Design and Research Northwestern Polytechnical UniversityXi’an 710072China China Aerodynamics Research and Development Center Mianyang 621000China

Rotor airfoil design is investigated in this paper. There are many difficulties for this highdimensional multi-objective problem when traditional multi-objective optimization methods are used. Therefore, a multi-layer hierarchical constraint method is proposed by coupling principal component analysis(PCA) dimensionality reduction and e-constraint method to translate the original high-dimensional problem into a bi-objective problem. This paper selects the main design objectives by conducting PCA to the preliminary solution of original problem with consideration of the priority of design objectives. According to the e-constraint method, the design model is established by treating the two top-ranking design goals as objective and others as variable constraints. A series of bi-objective Pareto curves will be obtained by changing the variable constraints, and the favorable solution can be obtained by analyzing Pareto curve spectrum. This method is applied to the rotor airfoil design and makes great improvement in aerodynamic performance. It is shown that the method is convenient and efficient, beyond which, it facilitates decision-making of the highdimensional multi-objective engineering problem.

关键词： Multi-layer hierarchical constraint method Multi-objective optimization NSGA II Pareto front principal component analysis Rotor airfoil

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Application of coupled XFEM-BCQO in the structural optimization of a circular tunnel lining subjected to a ground motion

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Frontiers of Structural and Civil Engineering 2019年第6期13卷 1495-1509页

作者： Nazim Abdul NARIMAN Ayad Mohammad RAMADAN Ilham Ibrahim MOHAMMAD Department of Civil Engineering Tishk International University-SulaimaniSulaimaniya 46001Iraq Mathematics Department-College of Science Sulaimani UniversitySulaimaniya 46001Iraq

A new structural optimization method of coupled extended finite element method and bound constrained quadratic optimization method(XFEM-BCQO)is adopted to quantify the optimum values of four design parameters for a circular tunnel lining when it is subjected to earthquakes.The parameters are:tunnel lining thickness,tunnel diameter,tunnel lining concrete modulus of elasticity and tunnel lining concrete density.Monte-Carlo sampling method is dedicated to construct the meta models so that to be used for the BCQO method using matlab codes.Numerical simulations of the tensile damage in the tunnel lining due to a real earthquake in the literature are created for three design cases.XFEM approach is used to show the cracks for the mentioned design cases.The results of the BCQO method for the maximum design case for the tunnel tensile damage was matching the results obtained from XFEM approach to a fair extent.The new coupled approach manifested a significant capability to predict the cracks and spalling of the tunnel lining concrete under the effects of dynamic earthquakes.

关键词： ovaling deformation monte carlo sampling XFEM-BCQO maximum principal stress

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Analysis to driving forces of land use change in Lu’an mining area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 727-732页

作者： LIU Chang-hua, MA Xiao-xiao School of Surveying and Land Information Engineering, Henan Polytechnic University, Jiaozuo 454003, China School of Surveying and Land Information Engineering Henan Polytechnic University Jiaozuo 454003 China

By selecting impact factors of driving force and formulating evaluation criteria of the impacts, the evaluation system of corresponding driving force impact of land use change was established. Taking Lu'an mining area as an example, the specific impact factors of coal mine were comprehensively evaluated and analyzed in order to carry out qualitative and quantitative analysis for the driving force of mining-land use change. The principal component analysis shows that the social and economic development in mining area from 2000 to 2007 demonstrates continuous accelerate trends, and the impacts of its overall driving force to land use change are increased gradually. The socio-economic factors have more impacts to mining-land use change than those of the natural resources. The main driving force of mining-land use change also include population, technological progress and policy.

关键词： mining area land use change driving force evaluation factor principal component analysis

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Driving factors of urban land growth in Guangzhou and its implications for sustainable development

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Frontiers of Earth Science 2019年第3期13卷 464-477页

作者： Xuezhu CUI Shaoying LI Xuetong WANG Xiaolong XUE School of Management Guangzhou UniversityGuangzhou 510000China School of Geographical Science Guangzhou UniversityGuangzhou 510000China

Since 2000, China’s urban land has expanded at a dramatic speed because of the country’s rapid urbanization. The country has been experiencing unbalanced development between rural and urban areas, causing serious challenges such as agricultural security and land resources waste. Effectively evaluating the driving factors of urban land growth is essential for improving efficient land use management and sustainable urban development. This study established a principal component regression model based on eight indicators to identify their influences on urban land growth in Guangzhou. The results provided a grouping analysis of the driving factors, and found that economic growth, urban population, and transportation development are the driving forces of urban land growth of Guangzhou, while the tertiary industry has an opposite effect. The findings led to further suggestions and recommendations for urban sustainable development. Hence, local governments should design relevant policies for achieving the rational development of urban land use and strategic planning on urban sustainable development.

关键词： driving factors urban land growth principal component regression land management policy sustainable development Guangzhou

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Prospectivity modeling of porphyry copper deposits: recognition of efficient mono-and multi-element geochemical signatures in the Varzaghan district, NW Iran

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Acta Geochimica 2019年第1期38卷 131-144页

作者： Reza Ghezelbash Abbas Maghsoudi Mehrdad Daviran Faculty of Mining and Metallurgical Engineering Amirkabir University of Technology School of Mining Petroleum and Geophysics EngineeringShahrood University of Technology

The Varzaghan district at the northwestern margin of the Urumieh–Dokhtar magmatic arc, is considered a promising area for the exploration of porphyry Cu deposits in Iran. In this study we identified mono-and multi-element geochemical anomalies associated with Cu–Au–Mo–Bi mineralization in the central parts of the Varzaghan district by applying the concentration–area fractal method. After mono-element geochemical investigations, principal component analysis was applied to ten selected elements in order to acquire a multi-element geochemical signature based on the mineralization-related component. Quantitative comparisons of the obtained fractal-based populations were carried out in accordance with known Cu occurrences using Student's t-values. Then,significant mono-and multi-element geochemical layers were separately combined with related geologic and structural layers to generate prospectivity models, using the fuzzy GAMMA approach. For quantitative evaluation of the effectiveness of different geochemical signatures in final prospectivity models, a prediction-area plot was adapted. The results show that the multi-element geochemical signature of principal component one(PC1) is more effective than mono-element layers in delimiting exploration targets related to porphyry Cu deposits.

关键词： Geochemical signature Concentration–area(C–A) fractal principal component analysis(PCA) Student’s t-value Fuzzy mineral prospectivity modeling(MPM) Prediction–area(P–A) plot

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A parallel and robust object tracking approach synthesizing adaptive Bayesian learning and improved incremental subspace learning

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Frontiers of Computer Science 2019年第5期13卷 1116-1135页

作者： Kang LI Fazhi HE Haiping YU Xiao CHEN State Key Laboratory of Software Engineering School of Computer Science Wuhan University Wuhan 430072 China School of Computer Science and Information Engineering Hubei University Wuhan 430062 China

This paper presents a novel tracking algorithm which integrates two complementary trackers. Firstly, an improved Bayesian tracker(B-tracker) with adaptive learning rate is presented. The classification score of B-tracker reflects tracking reliability, and a low score usually results from large appearance change. Therefore, if the score is low, we decrease the learning rate to update the classifier fast so that B-tracker can adapt to the variation and vice versa. In this way, B-tracker is more suitable than its traditional version to solve appearance change problem. Secondly, we present an improved incremental subspace learning method tracker(Stracker). We propose to calculate projected coordinates using maximum posterior probability, which results in a more accurate reconstruction error than traditional subspace learning tracker. Instead of updating at every time, we present a stopstrategy to deal with occlusion problem. Finally, we present an integrated framework(BAST), in which the pair of trackers run in parallel and return two candidate target states separately. For each candidate state, we define a tracking reliability metrics to measure whether the candidate state is reliable or not, and the reliable candidate state will be chosen as the target state at the end of each frame. Experimental results on challenging sequences show that the proposed approach is very robust and effective in comparison to the state-of-the-art trackers.

关键词： object tracking Bayesian learning subspace learning particle filter principal component analysis

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Global sensitivity analysis of certain and uncertain factors for a circular tunnel under seismic action

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Frontiers of Structural and Civil Engineering 2019年第6期13卷 1289-1300页

作者： Nazim Abdul NARIMAN Raja Rizwan HUSSAIN Ilham Ibrahim MOHAMMAD Peyman KARAMPOUR Department of Civil Engineering Tishk International University SulaimaniSulaimaniya 46001Iraq Civil Engineering Department College of EngineeringKing Saud UniversityRiyadh 11421Saudi Arabia Department of Mechanical Engineering Faculty of EngineeringArak UniversityArak 38156-875Iran

There are many certain and uncertain design factors which have unrevealed rational effects on the generation of tensile damage and the stability of the circular tunnels during seismic actions.In this research paper,we have dedicated three certain and four uncertain design factors to quantify their rational effects using numerical simulations and the Sobol's sensitivity indices.Main effects and interaction effects between the design factors have been determined supporting on variance-based global sensitivity analysis.The results detected that the concrete modulus of elasticity for the tunnel lining has the greatest effect on the tensile damage generation in the tunnel lining during the seismic action.In the other direction,the interactions between the concrete density and both of concrete modulus of elasticity and tunnel diameter have appreciable effects on the tensile damage.Furthermore,the tunnel diameter has the deciding effect on the stability of the tunnel structure.While the interaction between the tunnel diameter and concrete density has appreciable effect on the stability process.It is worthy to mention that SoboFs sensitivity indices manifested strong efficiency in detecting the roles of each design factor in cooperation with the numerical simulations explaining the responses of the circular tunnel during seismic actions.

关键词： shear waves SoboFs sensitivity indices maximum principal stress maximum overall displacement tensile damage

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Unified analytical solution for deep circular tunnel with consideration of seepage pressure,grouting and lining

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Journal of Central South University 2017年第6期24卷 1483-1493页

作者：李学峰杜守继陈兵 Department of Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China

A new unified analytical solution is presented for predicting the range of plastic zone and stress distributions around a deep circular tunnel in a homogeneous isotropic continuous medium. The rock mass, grouting zone and lining are assumed as elastic-perfectly plastic and governed by the unified strength theory(UST). This new solution has made it possible to consider the interaction between seepage pressure, lining, grouting and rock mass, and the intermediate principal stress effect together. Moreover, parametric analysis is carried out to identify the influence of the related parameters on the plastic zone radius. Under the given conditions, the results show that the plastic zone radius decreases with an increasing cohesion, internal friction angle and hydraulic conductivity of lining and unified failure criterion parameter, respectively; whereas the plastic zone radius increases with the growth of elasticity modulus of lining. Comparison of results from the new solution and the other published one shows well agreement and provides confidence in the new solution proposed.

关键词： unified strength theory (UST) intermediate principal stress seepage pressure grouting lining analytical solution

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Feasibility study on determining the conventional true value of gamma-ray air kerma in a minitype reference radiation

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Nuclear Science and Techniques 2017年第6期28卷 133-139页

作者： Yi-Xin Liu Biao Wei Yang Xu Meng He Ren-Hong Zhuo De-Zhi Wen Da-Jie Ding Ben-Jiang Mao Key Laboratory of Optoelectronics Technology and System Ministry of EducationChongqing University Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics

A minitype reference radiation(MRR) with dimensions of only 1 m × 1 m × 1 m has been developed for the in situ calibration of photon dosimeters.The present work conducts a feasibility study on determining the conventional true value of gamma-ray air kerma at the point of test in the MRR.Owing to its smaller dimensions,the scattered gamma-rays in the MRR are expected to induce a non-negligible interference with the radiation field compared with conditions in the standard reference radiation stipulated by ISO4037-1 or GB/T12162.1.A gamma-ray spectrometer was employed to obtain the spectra of scattered gamma-rays within the MRR,and the feature components of the spectra were extracted by principal component analysis to characterize the interference of a dosimeter probe in the radiation field.A prediction model of the CAK at the point of test was built by least squares support vector machine based on the feature component data obtained from nine sample dosimeters under five different dose rates.The mean prediction error of the CAK prediction model was within ±4.5%,and the maximum prediction error was about ±10%.

关键词： Air kerma Reference radiation Calibration principal component analysis Support vector machine

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