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An Uncertain Programming Model for Land Use Structure Optimization to Promote Effectiveness of Land Use Planning

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Chinese Geographical Science 2017年第6期27卷 974-988页

作者： LI Xin ma xiaodong School of Geography Geomatics and Planning Jiangsu Normal University Department of Earth and Environmental Sciences University of British Columbia

Land use structure optimization(LUSO) is an important issue for land use planning. In order for land use planning to have reasonable flexibility, uncertain optimization should be applied for LUSO. In this paper, the researcher first expounded the uncertainties of LUSO. Based on this, an interval programming model was developed, of which interval variables were to hold land use uncertainties. To solve the model, a heuristics based on Genetic Algorithm was designed according to Pareto Optimum principle with a confidence interval under given significance level to represent LUSO result. Proposed method was applied to a real case of Yangzhou, an eastern city in China. The following conclusions were reached. 1) Different forms of uncertainties ranged from certainty to indeterminacy lay in the five steps of LUSO, indicating necessary need of comprehensive approach to quantify them. 2) With regards to trade-offs of conflicted objectives and preferences to uncertainties, our proposed model displayed good ability of making planning decision process transparent, therefore providing an effective tool for flexible land use planning compiling. 3) Under uncertain conditions, land use planning effectiveness can be primarily enhanced by flexible management with reserved space to percept and hold uncertainties in advance.

关键词： land use structure optimization (LUSO) uncertainties flexibility land use planning decision support system effectiveness

Feature fusion method for edge detection of color images

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Journal of Systems Engineering and Electronics 2009年第2期20卷 394-399页

作者： ma Yu Gu xiaodong Wang Yuanyuan Dept. of Electronic Engineering Fudan Univ. Shanghai 200433 P. R. China

A novel feature fusion method is proposed for the edge detection of color images. Except for the typical features used in edge detection, the color contrast similarity and the orientation consistency are also selected as the features. The four features are combined together as a parameter to detect the edges of color images. Experimental results show that the method can inhibit noisy edges and facilitate the detection for weak edges. It has a better performance than conventional methods in noisy environments.

关键词： color image processing edge detection feature extraction feature fusion

An Improvement of the Rational Representation for High-Dimensional Systems

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Journal of Systems Science & Complexity 2021年第6期34卷 2410-2427页

作者： XIAO Fanghui LU Dong ma xiaodong WANG Dingkang KLMM Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China Beijing Advanced Innovation Center for Big Data and Brain Computing Beihang UniversityBeijing 100191China School of mathematical Sciences Beihang UniversityBeijing 100191China College of Science China Agricultural UniversityBeijing 100083China

Based on the rational univariate representation of zero-dimensional polynomial systems,Tan and Zhang proposed the rational representation theory for solving a high-dimensional polynomial system,which uses so-called rational representation sets to describe all the zeros of a high-dimensional polynomial *** paper is devoted to giving an improvement for the rational *** idea of this improvement comes from a minimal Dickson basis used for computing a comprehensive Grobner system of a parametric polynomial system to reduce the number of *** authors replace the normal Grobner basis G satisfying certain conditions in the original algorithm(Tan-Zhang’s algorithm)with a minimal Dickson basis G_(m) of a Grobner basis for the ideal,where G_(m) is smaller in size than *** on this,the authors give an improved ***,the proposed algorithm has been implemented on the computer algebra system *** data and its performance comparison with the original algorithm show that it generates fewer branches and the improvement is rewarding.

关键词： Comprehensive Grobner systems high-dimensional polynomial system rational representation rational univariate representation

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Computing polynomial univariate representations of zero-dimensional ideals by Grbner basis

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Science China mathematics 2012年第6期55卷 1293-1302页

作者： ma xiaodong SUN Yao WANG DingKang KLMM Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China

Rational Univariate Representation （RUR） of zero-dimensional ideals is used to describe the zeros of zero-dimensional ideals and RUR has been studied extensively. In 1999, Roullier proposed an efficient algorithm to compute RUR of zero-dimensional ideals. In this paper, we will present a new algorithm to compute Polynomial Univariate Representation （PUR） of zero-dimensional ideals. The new algorithm is based on some interesting properties of Grobner basis. The new algorithm also provides a method for testing separating elements.

关键词： RUR PUR zero-dimensional ideals Grobner basis

On computing Grbner bases in rings of differential operators

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Science China mathematics 2011年第6期54卷 1077-1087页

作者： ma xiaodong SUN Yao WANG DingKang KLMM Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

Insa and Pauer presented a basic theory of Grobner basis for differential operators with coefficients in a commutative ring in 1998, and a criterion was proposed to determine if a set of differential operators is a GrSbner basis. In this paper, we will give a new criterion such that Insa and Pauer＇s criterion could be concluded as a special case and one could compute the Grobner basis more efficiently by this new criterion.

关键词： Grobner basis rings of differential operators

Recent progress in upgrading metallurgical-grade silicon to solar-grade silicon via pyrometallurgical routes

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International Journal of Minerals,Metallurgy and materials 2022年第4期29卷 767-782页

作者： Yun Lei xiaodong ma Ye Wang Zhiyuan Chen Yongsheng Ren Wenhui ma Kazuki Morita Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China Sustainable Minerals Institute The University of QueenslandSt Lucia 4072QLDAustralia School of Chemical Engineering Sichuan UniversityChengdu 610065China Separation and Conversion Technology Flemish Institute for Technological ResearchMol 2400Belgium Department of materials Engineering Graduate School of EngineeringThe University of TokyoTokyo 113-8656Japan

Si-based photovoltaic solar power has been rapidly developed as a renewable and green energy *** widespread use of Sibased solar cells requires large amounts of solar-grade Si(SoG-Si)to manufacture Si *** routes,mainly the modified Siemens process,have dominated the preparation of polycrystalline SoG-Si;however,traditional chemical techniques employ a series of complex chemical reactions involving various corrosive and hazardous *** addition,large amounts of complex waste solar cells and Si kerf slurry waste gradually accumulate and are difficult to recycle using these *** methods are required to meet the demand for SoGSi preparation and Si waste *** metallurgical route shows promise but is hindered by the problem of eliminating B and P from metallurgical-grade Si(MG-Si).Various pyrometallurgical treatments have been proposed to enhance the removal of B and P from *** article reviews Si refining with slag treatment,chlorination,vacuum evaporation,and solvent refining,and summarizes and discusses the basic principles and recent representative studies of the four *** these,solvent refining is the most promising and environmentally friendly approach for obtaining low-cost SoG-Si and is a popular research ***,a simple and green approach,i.e.,a combination of solvent refining,slag treatment,or vacuum directional solidification,is proposed for low-cost SoG-Si preparation using MG-Si or Si wastes as raw materials.

关键词： silicon refining solar-grade silicon solvent refining vacuum evaporation slag treatment Si kerf slurry waste

Influences of different Zr/Sc ratios on microstructure and mechanical properties of Al-2Si alloy

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Journal of Rare Earths 2021年第1期39卷 105-112,I0004页

作者： Qinglin Li xiaodong ma Binqiang Li Jiqiang ma Xiangyu Feng Ruijie Pei Jianjun Liu School of materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou 730050China School of materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

The influences of different Zr/Sc ratios on the microstructural evolution and mechanical performances of Al-2 Si alloy were investigated in this *** as-cast samples were characterized and analyzed by the scanning electron microscope(SEM)with an energy dispersive spectrometer(EDS)to indicate the refining effect of the different Zr/Sc ratios on theα-Al and Si phases in Al-2 Si *** results indicate that theα-Al phases are refined from coarse dendritic structure to relatively fine equiaxed grains when the Zr/Sc ratio is equal to 1:***,the eutectic Si phase in Al-2 Si-0.2 Zr-0.2 Sc alloy is modified from the coarse plate and needle to fine fiber and partial granular structure,and the average roundness of eutectic Si is decreased by 75%from 16 to *** the refinement ofα-Al phases and the modification of eutectic Si structure,the ultimate tensile strength(UTS)is improved by 53%and the elongation(EL)is increased by 64%when the Zr/Sc ratio is equal to 1:*** addition,the UTS decreases and EL is enhanced with the increase of tensile ***,the fracture model of Al-2 Si-0.2 Zr-0.2 Sc alloy in250℃changes into the ductile fracture.

关键词： Al-Si alloy Zr/Sc ratio α-Al phases Eutectic Si Mechanical properties Rare earths

Reliability analysis based on a novel density estimation method for structures with correlations

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Chinese Journal of Aeronautics 2017年第3期30卷 1021-1030页

作者： Baoyu LI Leigang ZHANG Xuejun ZHU Xiongqing YU xiaodong ma College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China China Academy of Launch Vehicle Technology Beijing 100076 China

Estimating the Probability Density Function（PDF） of the performance function is a direct way for structural reliability analysis,and the failure probability can be easily obtained by integration in the failure ***,efficiently estimating the PDF is still an urgent problem to be *** existing fractional moment based maximum entropy has provided a very advanced method for the PDF estimation,whereas the main shortcoming is that it limits the application of the reliability analysis method only to structures with independent *** in fact,structures with correlated inputs always exist in engineering,thus this paper improves the maximum entropy method,and applies the Unscented Transformation（UT） technique to compute the fractional moments of the performance function for structures with correlations,which is a very efficient moment estimation method for models with any *** proposed method can precisely estimate the probability distributions of performance functions for structures with ***,the number of function evaluations of the proposed method in reliability analysis,which is determined by UT,is really *** examples are employed to illustrate the accuracy and advantages of the proposed method.

关键词： Fractional moment maximum entropy Probability density function Reliability analysis Unscented transformation

Preparation,characterization and catalytic behavior of hierachically porous CuO/α-Fe_2O_3/SiO_2 composite material for CO and o-DCB oxidation

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Journal of Natural Gas Chemistry 2011年第6期20卷 618-622页

作者： xiaodong ma Xi Feng Xuan He Hongwen Guo Lu Lu Key Laboratory of Environmental Pollution Process and Standard Ministry of Education Tianjin Key Laboratory of Environmental Remediation and Pollution Control College of Environmental Science and Engineering Nankai University Tianjin 300071 China

Hierachically porous （HP） CuO/α-Fe2O3/SiO2 composite material was fabricated by sol-gel method and multi-hydrothermal processes using HP-SiO2 as *** resulting material was characterized by N2 adsorption-desorption,X-ray diffraction and scanning electron *** as-prepared CuO/Fe2O3/HP-SiO2 sample,with α-Fe2O3 and CuO nanocrystals,possessed a co-continuous skeleton,through-macroporous and mesoporous *** catalytic behavior for CO and o-DCB oxidation was *** result showed that CuO/Fe2O3/HP-SiO2 catalyst exhibited high catalytic activity for both CO and o-DCB oxidation,indicating its potential application in combined abatement of CO and chlorinated volatile organic compounds.

关键词： CO and o-DCB oxidation hierachically porous CuO/α-Fe2O3/HP-SiO2 monolith