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Impacts of anthropogenic and biophysical factors on ecological land using logistic regression and random forest:A case study in Mentougou District,Beijing,China

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Journal of Mountain Science 2022年第2期19卷 433-445页

作者： TIAN Chao CHENG lin-lin yin Ting-ting College of Geoscience and Surveying Engineering China University of Mining and Technology(Beijing)Beijing 100083China

Ecological land is an important guarantee to maintain urban ecological security and sustainable *** increasing studies have been brought to ecological land,with few explorations of the relative importance of anthropogenic-natural factors and how they interact to induce the ecological land *** research sought to fill this *** this study,18 factors,including the risk of goaf collapse,fault,prime croplands,were selected from six aspects of topography,geology,climate,accessibility,socio-economic and land control *** regression(LR)and random forest(RF)models were adopted to identify the anthropogenic and biophysical factors on the dynamic change of ecological land of Mentougou in Beijing from 1990 to *** results show that there was a significant increase in ecological land from 1990 to *** increased area of ecological land reached 102.11 km2 with an increased rate of 0.78,the gravity center of ecological land gradually moved to the *** impact of anthropogenic factors on ecological land was greater than that of natural factors,ecological land was mainly driven by proportion of prime cropland,per capita GDP,land urbanization,temperature,per capita rural income,elevation and aspect ***,slope and precipitation were also identified as important predictors for ecological land *** model comparison suggested that RF can better identify the relationship between ecological land and explanatory variables than LR *** on our findings,the implementation of government policies along with anthropogenic factors are the most important variables influencing ecological land change,and the rational planning and allocation of ecological land by Mentougou government are still needed.

关键词： Logistic regression Random forest Ecological land Determinants Dynamic change

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Weighted estimates for commutators of singular integral operators with non-smooth kernels

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Applied Mathematics(A Journal of Chinese Universities) 2010年第3期25卷 318-324页

作者： ZHANG lin JIANG yin-sheng Department of Applied Mathematics Xinjiang Institue of Finance and Economics Xinjiang 830012 China. College of Mathematics and Systems Science Xinjiang University Xinjiang 830046 China

In this paper, we establish the boundedness of commutators of singular integral operators with non-smooth kernels on weighted Lipschitz spaces Lipβ,ω. The condition on the kernel in this paper is weaker than the usu... 详细信息

关键词： Lipβ,ω space commutator singular integral operator non-smooth kernel.

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Applications of Raman spectroscopy in two-dimensional materials

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Journal of Innovative Optical Health Sciences 2020年第5期3卷 42-62页

作者： Pengkun yin Qingyu lin Yixiang Duan College of Life Sciences Research Center of Analytical Instrumentation Key Laboratory of Bio-resource and Eco-environment Ministry of Education Sichuan University 610064 ChengduP.R.China

At present,two-dimensional(2D)materials have shown great application potential in numerous fields based on their physical chemical and electronic *** spectroscopy and de-rivative techniques are effective tools for characterizing 2D *** spectroscopy conveys lots of knowledge on 2D materials,including layer number,doping type,strain and interlayer *** review summarized advanced applications of Raman spectroscopy in 2D *** challenges and possible applied directions of Raman spectroscopy to 2D materials are discussed in detail.

关键词： Raman spectroscopy and derivative techniques monolayer materials nondestructive characterization

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A 3D shell-like approach using element-free Galerkin method for analysis of thin and thick plate structures

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Acta Mechanica Sinica 2013年第1期29卷 85-98页

作者： Yu yin lin-Quan Yao Yang Cao School of Mathematical Science Soochow University School of Urban Rail Transportation Soochow University School of Transportation Nantong University

A new efficient meshless method based on the element-free Galerkin method is proposed to analyze the static deformation of thin and thick plate structures in this paper. Using the new 3D shell-like kinematics in analogy to the solid-shell concept of the finite element method, discretization is carried out by the nodes located on the upper and lower surfaces of the structures. The approximation of all unknown field variables is carried out by using the moving least squares （MLS） approximation scheme in the in-plane directions, while the linear interpolation is applied through the thickness direction. Thus, different boundary conditions are defined only using displacements and penalty method is used to enforce the essential boundary conditions. The constrained Galerkin weak form, which incorporates only dis- placement degrees of freedom （d.o.f.s）, is derived. A modified 3D constitutive relationship is adopted in order to avoid or eliminate some self-locking effects. The numeric efficiency of the proposed meshless formulation is illustrated by the numeric examples.

关键词： Meshless methods 3D shell-like Moving least squares approximation Self-locking Thin plate

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Isolated Bipolar Modular Multilevel DC-DC Converter with Self-balancing Capability for Interconnection of MVDC and LVDC Grids

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CSEE Journal of Power and Energy Systems 2023年第1期9卷 365-379页

作者： Jinmu Lai Xin yin Yaoqiang Wang lin Jiang Zia Ullah Xianggen yin School of Electrical and Information EngineeringZhengzhou UniversityZhengzhou 450001China Department of Electrical Engineering and ElectronicsUniversity of LiverpoolLiverpoolUK State Key Laboratory of Advanced Electromagnetic Engineering and TechnologyHuazhong University of Scienceand TechnologyWuhan 430074China

Bipolar medium-voltage DC(MVDC)and lowvoltage DC(LVDC)grids have the advantages of flexible integration of distributed renewable-energy generation and reliable power *** order to achieve voltage conversion,power transfer,and electrical isolation for bipolar MVDC and LVDC grids,a high-power DC-DC converter is ***,this paper proposes an isolated bipolar modular multilevel DCDC converter(BiMMDC)with power self-balancing capability for interconnection of MVDC and LVDC *** proposed BiMMDC consists of two series connected MMCs in the MV stage to configure a bipolar MVDC interface,and interleaved converters combined with a dual-transformer are designed in the LV stage to configure the bipolar LVDC interface and to provide a self-balancing *** circuits of two series-connected MMCs and a dual-transformer with interleaved converters are *** that,operation principles of the proposed BiMMDC are introduced,considering balanced/unbalanced power transfer of bipolar LVDC grid and monopolar shortcircuit or open-circuit faults at MVDC *** control scheme is also presented for the proposed BiMMDC under different operating ***,a Matlab simulation and controller hardware-in-the-loop(CHIL)evaluation results are provided to validate the feasibility and effectiveness of the proposed typology and its operating performance.

关键词： Bipolar DC-DC converter equivalent circuit modular monopolar operation multilevel self-balancing

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A Multi-Condition Relighting with Optimal Feature Selection to Robust Face Recognition with Illumination Variation

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China Communications 2014年第6期11卷 99-107页

作者： HAO Yujie lin Jie yin Shi School of Computer Science and Engineering University of Electronic Science and Technology of China Department of Computer Science University of Illinois at Chicago

In this paper, we proposed a new approach for face recognition with robust to illumination variation. The improved performance to various lights in recognition is obtained by a novel combination of multicondition relighting and optimal feature selection. Multi-condition relighting provides a "coarse" compensation for the variable illumination, and then the optimal feature selection further refines the compensation, and additionally offers the robustness to shadow and highlight, by deemphasizing the local mismatches caused by imprecise lighting compensation, shadow or highlight on recognition. For evaluation, two databases with various illumination mismatches have been used. The results have demonstrated the improved robustness of the new methods.

关键词： relighting illumination variation robustness face recognition.

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Modular Design Using Sustainable Luminescent Materials in Energy-Saving Reflective Cat’s Eyes for Public Road Safety Planning

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Journal of Renewable Materials 2022年第5期10卷 1415-1437页

作者： Lung-yin lin Yu-Shing Chang Department of Industrial Design National Kaohsiung University of Science and TechnologyKaohsiung82445Taiwan Department of Business Administration National Taichung University of Science and TechnologyTaichung404Taiwan

Recently,there has been a global movement toward environmental protection and energy conservation through the design and development of new products in accordance with sustainable *** this study,rare earth luminescent materials were used owing to their active light emission and ***,solar lightemitting diode lights and car-light reflection were utilised to increase the recognition and reliability of reflective cat *** with carbon reduction,this can save energy and enhance road *** study considered the Theory of Inventive Problem Solving and a literature review to analyse the issues in existing ***,expert interviews were conducted to screen projects and develop product design ***,the ratio of light-storage materials was experimentally determined and the prototypes *** cat’s eye addresses the shortcomings identified in previous analyses of existing *** applied energy storage environmental protection materials,together with material proportioning(which balanced warning efficiency against cost-effectiveness)to develop diversified modular kits;these were flexible in terms of quantity and easily *** study achieved four key objectives:(1)reducing the research and development costs of the manufacturer;(2)offering buyers a diverse suite of products;(3)responding to a need to improve diverse road user safety;and(4)reducing government procurement costs for safety warning *** results provide a reference for the creative modular design of energy-saving products for public road safety planning in various industries.

关键词： Sustainable luminescent materials modular design TRIZ expert interview diverse road safety

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Populations of Ethanol Conformers in Liquid CCI4 and CS2 by Raman Spectra in OH Stretching Region

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Chinese Journal of Chemical Physics 2015年第3期28卷 245-252,I0001页

作者： Nai-yin Hu Ke lin Xiao-guo Zhou Shi-lin Liu Hefei National Laboratory for Physical Sciences at the Microscale Department of Chemical PhysicsUniversity of Science and Technology of China Hefei 230025 China Synergetic Innovation Center of Quantum Information & Quantum Physics University of Science and Technology of China Hefei 230026 China

Combining Raman spectroscopy with density functional theory, the populations of the trans- and gaucheethanol conformers are investigated in carbon tetrachloride （CC14） and carbon disulfide （CS2）. The spectral contributions of two ethanol conformers are identified in OH stretching region. The energy difference between both conformers is estimated with the aid of the calculated Raman cross sections. It can be seen that the trans- ethanol is more stable in CC14 and CS2 solutions. The spectra are also obtained at different temperatures, and it is found the van＇t Hoff analysis is invalid in these solutions. By taking accounts of the Boltzmann distribution and theoretical Raman cross section, the energy difference is found to be increased with temperature, which shows the weak intermolecular interactions can enhance the population of transethanol.

关键词： Raman spectroscopy Ethanol Conformer Energy difference

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Low-Brightness Object Recognition Based on Deep Learning

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Computers, Materials & Continua 2024年第5期79卷 1757-1773页

作者： Shu-yin Chiang Ting-Yu lin Department of Information and Telecommunications Engineering Ming Chuan UniversityTaoyuan City333Taiwan

This research focuses on addressing the challenges associated with image detection in low-light environments,particularly by applying artificial intelligence techniques to machine vision and object recognition *** primary goal is to tackle issues related to recognizing objects with low brightness *** this study,the Intel RealSense Lidar Camera L515 is used to simultaneously capture color information and 16-bit depth information *** detection scenarios are categorized into normal brightness and low brightness *** the system determines a normal brightness environment,normal brightness images are recognized using deep learning *** low-brightness situations,three methods are proposed for *** first method is the SegmentationwithDepth image(SD)methodwhich involves segmenting the depth image,creating amask from the segmented depth image,mapping the obtained mask onto the true color(RGB)image to obtain a backgroundreduced RGB image,and recognizing the segmented *** second method is theHDVmethod(hue,depth,value)which combines RGB images converted to HSV images(hue,saturation,value)with depth images D to form HDV images for *** third method is the HSD(hue,saturation,depth)method which similarly combines RGB images converted to HSV images with depth images D to form HSD images for *** experimental results,in normal brightness environments,the average recognition rate obtained using image recognition methods is 91%.For low-brightness environments,using the SD method with original images for training and segmented images for recognition achieves an average recognition rate of over 82%.TheHDVmethod achieves an average recognition rate of over 70%,while the HSD method achieves an average recognition rate of over 84%.The HSD method allows for a quick and convenient low-light object recognition *** research outcome can be applied to nighttime surveillance systems or nighttime road safety systems

关键词： Low-brightness depth image image segmentation image recognition HDV HSD

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A Compact and Wavelength-Tunable PPLN Electro-optics Q-Switched Laser with Intra-Cavity Optical Parametric Generation

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Chinese Physics Letters 2013年第9期30卷 58-60页

作者： CHIANG An-Chung lin Yen-yin Nuclear Science and Technology Development Center National Tsing-Hua UniversityHsinchu 30013 Institute of Photonics Technologies National Tsing-Hua UniversityHsinchu 30013

We report a compact and wavelength-tunable periodically poled lithium niobate(PPLN)Q-switched laser with intra-cavity optical parametric generation,producing 8-ns,10-𝜈μJ pulses at 10-kHz repetition rate when pumped with a 10-W diode laser at *** output wavelength can be tuned from 1450nm to ***-pulse generation was observed in the experiment.

关键词： pumped switched tunable

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