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Research progress and prospects of coal petrology and coal quality in China

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International Journal of Coal Science & Technology 2020年第2期7卷 273-287页

作者： Yuegang Tang Ruiqing Li Shaoqing Wang college of Geoscience and surveying Engineering China University of Mining and Technology(Beijing)Beijing100083China

Clean utilization of coal depends on the quality of raw coal,which depends on the coal-forming parent materials(petrology and chemical composition of coal),the multiple media of the coal-forming environment,and some epigenetic conditions,such as thermal evolution(coalification),magmatic hydrothermal fluid,*** on the research results of predecessors and prediction studies of coal resources since the founding of China,the present status of research on coal petrology,coal quality,coal metamorphism,and coal geochemistry in China is discussed in detail,with emphasis on research progress and the general situation of highly efficient and clean utilization of coal in the technical fields of coking,pyrolysis,combustion,gasification,and liquefaction,and the development prospects of coal petrology and coal quality in China are prospected.

关键词： Coal petrology Coal quality Coal metamorphism Coal geochemistry Research status Prospect

Accessibility Analysis of Healthcare Delivery System within Enugu Urban Area Using Geographic Information System

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Journal of Geographic Information System 2012年第4期4卷 312-321页

作者： Ifeanyi R. Ejiagha Johnbusco C. Ojiako Chijioke G. Eze Department of surveying and geoinformatics Akanu Ibiam Federal Polytechnic Afikpo Nigeria Department of surveying and geoinformatics Nnamdi Azikiwe University Awka Nigeria Joint Operations Centre Defence Headquarters Abuja Nigeria

The problem of accessibility of health institution, with respect to the available facility to serve the entire population leaving in an area, can be solved using GIS. This paper presents an analysis on accessibility of healthcare facilities in Enugu urban area in a GIS environment. This was achieved through acquisition of a base map of Enugu State showing geographic extent of Enugu Urban, determining the geometric positions of health institutions in Enugu urban using handheld GPS, Creation of a spatial database of existing healthcare facilities and demonstrating through various analyses the potentials of GIS in measurement of accessibility to healthcare facilities in Enugu urban Area. The analysis includes network analysis, used to determine the closeness of a facility and shortest route to these healthcare facilities. ARCGIS 9.3 was the main software used. This was supported by Geocal for coordinate conversion and Microsoft office packages. The result of the study showed the spatial distribution of health institutions, closest facilities in case of emergency and route to those health institutions within Enugu urban Area. It was noticed that most of the healthcare facilities were located within Enugu North local government area (LGA). Other settlements and LGAs had fewer healthcare facilities. Areas deprived of healthcare facility were also identified. Routes and closest facilities to those deprived areas were identified in the settlements/area. The analysis showed the efficacy of GIS in determining accessibility of healthcare institutions in Enugu urban area. The study is thus, recommended as a spatial decision support system for decisions regarding spatial accessibility of healthcare facilities in an urban area.

关键词： GIS Accessibility Database Healthcare Facilities District Health System

Several Kinematic Data Processing Methods for Time-Correlated Observations

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Journal of Geodesy and Geoinformation Science 2019年第4期2卷 1-9页

作者： Bofeng LI Zhetao ZHANG college of surveying and geoinformatics Tongji UniversityShanghai 200092China School of Earth Sciences and Engineering Hohai UniversityNanjing 211100China

Time correlations always exist in modern geodetic data,and ignoring these time correlations will affect the precision and reliability of *** this paper,several methods for processing kinematic time-correlated observations are ***,the method for processing the time-correlated observations is expanded and *** on the theory of maximum a posteriori estimation,the third idea is proposed after the decorrelation transformation and differential *** types of situations with and without common parameters are both investigated by using the decorrelation transformation,differential transformation and maximum a posteriori estimation ***,the characteristics and equivalence of above three methods are ***,in order to balance the computational efficiency in real applications and meantime effectively capture the time correlations,the corresponding reduced forms based on the autocorrelation function are ***,with GPS real data,the correctness and practicability of derived formulae are evaluated.

关键词： time correlation kinematic solution decorrelation transformation differential transformation maximum a posteriori estimation

Effects of polarization calibration on aerosol optical depth retrieval: An ocean case sensitivity analysis

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Science China Earth Sciences 2015年第6期58卷 939-948页

作者： LIU TianYue CHI TianHe CHEN Wei Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences college of Earth Sciences University of Chinese Academy of Sciences college of Geoscience and surveying Engineering China University of Mining and Technology

Reflectance measurements of both the visible and infrared bands of passive remote sensing sensors are widely used to retrieve aerosol optical depth(AOD) information. This is performed commonly for data obtained over both ocean and land, and these measurements allow for the off line development of a lookup table using radiative transfer models. Owing to molecular and aerosol effects, the reflected light received by the sensor is usually highly polarized. The linear polarization effect may be up to 100%, and the polarization factor of a sensor optical system will change the total intensity as well as the polarization status of the signal reaching the detector. The detector response will be different when the incident light polarization status changes, even if the total intensity remains constant. However, if the polarization calibration is neglected, it will cause obvious errors in the aerosol data retrieval. This is especially true for aerosol optical depth retrieval over an ocean. This measurement relies directly on the reflectance output of the sensor. Cases involving land surfaces are not discussed herein because the inhomogeneous properties conceal the error due to polarization. Taking the 550 and 860 nm bands as examples, the difference between the real top-of-atmosphere(TOA) reflectance and the reflectance reaching the detector is calculated using three different sensor polarization standards according to the Sea-viewing Wide Field-of-view Sensor(Sea Wi FS) and Moderate Resolution Imaging Spectroradiometer(MODIS) standards. The differences in AOD retrieval are also demonstrated using the lookup table developed previously from a vector radiative transfer code. The results reveal that under a normal situation in which the AOD is 0.15, the maximum AOD retrieval error could reach 0.04 in 550 nm but only 0.02 in 860 nm for the dust aerosol model. For the soot aerosol model, the maximum AOD retrieval error is 0.1 in 550 nm and 0.12 in 860 nm, indicating that the lack

关键词： aerosol polarization calibration radiative transfer

Effects of Industrial Relocation on Chinese Regional Economic Growth Disparities: Based on System Dynamics Modeling

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Chinese Geographical Science 2014年第6期24卷 706-716页

作者： WU Aizhi LI Guoping SUN Tieshan LIANG Yusheng Library Peking University School of Government Peking University college of Geoscience and surveying Engineering China University of Mining and Technology

The economic growth of China has led to increasing growth disparities between regions. Such disparities are uncontrolled and are severely negative symptoms in the process of economic development. On the basis of system dynamics(SD) modeling and the relationship between industrial relocation and regional economic growth, we construct a model of the interrelationship between the two aforementioned phenomena. The model is an effective and creative exploration for examining effects of industrial relocation on Chinese regional economic growth disparities. The SD model is employed in this study to build an inter-regional labor migration SD model, an inter-regional capital migration SD model, an intra-industry SD model, an intra-regional population SD model, and an intra-regional SD model which are based on realities in labor and capital flow from the view of industrial relocation. VENSIM software is utilized to perform a system simulation based on the data of the eastern, middle, and western regions from 2000 to 2010. Results show that industrial relocation gradually narrows the relative disparity in GDP among the three regions. Moreover, the absolute one is enlarged continuously. The absolute and relative disparities in per capita GDP among eastern, middle, and western regions generally exhibit decreasing trends.

关键词： industrial relocation economic growth disparity system dynamics (SD) modeling China

Evaluating urban development and socio-economic disparity in India through nighttime light data

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Journal of Geographical Sciences 2024年第12期34卷 2440-2456页

作者： YU Jingtong LIU Lingcen BAN Yifang ZHANG Qian college of Land Science and Technology China Agricultural UniversityBeijing 100083China Division of geoinformatics KTH Royal Institute of TechnologyStockholm 10044Sweden

Balanced development and the reduction of inequality are central objectives of the United Nations Sustainable Development Goals(SDGs).This study explores the use of Nighttime Light(NTL)brightness and the Nighttime Light Development Index(NLDI)as indicators of socioeconomic development in urban centers,focusing on six Indian *** examines the correlation between these indices and socioeconomic inequality across affluent neighborhoods,urban slums,downtown areas,and general urban areas in 2015,2018,and *** results reveal that lighting brightness in affluent areas can be lower than that in bustling downtowns,due to factors such as lower residential *** challenges the conventional assumption that higher NTL necessarily indicates greater *** study further confirmed significant developmental disparities between well-lit downtowns and poorly illuminated peripheral slum areas,as reflected by lower NLDI ***,the results uncover a phenomenon termed“same value but different spectrum”based on a careful examination of NLDI values of urban centers and their corresponding *** suggests that NLDI alone may not fully capture the complexity of urban development,and that underlying development trajectories,along with on-the-ground realities,must be further *** findings emphasize the importance of applying NLDI for urban internal *** addition,the study highlights the necessity for nuanced urban planning and targeted policy interventions specifically tailored to the unique conditions of different urban areas.

关键词： socio-economic inequality Nighttime Light Development Index(NLDI) regional disparity Indian cities

Research and implementation of a universal workflow model to evaluate the soil fertility based on OGC Web Service

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Geo-Spatial Information Science 2018年第4期21卷 346-357页

作者： Yan Ren Jiaying Chen Lankang Chen Haitao Zhang Ke Zhang Land surveying and Mapping Institute of Guangxi Zhuang Autonomous Region NanningChina college of Resources and Environment Huazhong Agricultural UniversityWuhanChina

A method based on workflow technology and Open Geospatial Consortium(OGC)specification is proposed to establish a universal workflow conceptual model in the network *** this paper,the soil fertility evaluation conceptual model was developed as an evaluation method of soil fertility by analyzing the GIS-based fertility evaluation method and extracting the dynamic variable to verify the feasibility *** validation process involves determining the instantiation of the conceptual *** proposed conceptual model achieved the following *** data acquisition and processing functions were packaged into an OGC-compliant service model;these service models were organized into a processing chain in a certain order on the workflow platform by Petri-Net;the fertility evaluation was realized on the workflow platform by calling the processing *** showed that processing functions and data can be shared in the network environment,and the network workflow model can be realized by the workflow *** successful implementation of fertility evaluation proved the feasibility of the network-based universal workflow conceptual *** addition,the flexibility of our modeling method is demonstrated by reconstructing the workflow model.

关键词： OGC Web Service conceptual model workflow fertility evaluation

Vibration reduction analysis of new barriers in large model experiment

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Earthquake Engineering and Engineering Vibration 2022年第3期21卷 741-751页

作者： Ding Guangya Shen Chenli Wang Jun Wu Ming college of Civil Engineering and Architecture Wenzhou UniversityWenzhou 325035China School of Geological Engineering and surveying Chang’an UniversityXi’an 710054China

A large model box was developed in our experiment to study the vibration reduction *** hydraulic highperformance actuators are arranged in the upper part of the model *** is a time difference between adjacent actuators,which can simulate the train induced *** reduce vibration a composite barrier is designed;the barrier consists of a honeycomb concrete canvas and PE polymer water *** concrete canvas can be mixed with water to produce a hydration reaction to form a structure with a certain *** simulating different train speeds and loads,vertical vibration velocity,and acceleration before and after the barrier are compared and *** experimental results show that the new barrier can achieve a good vibration reduction *** the simulated train speed increases,the damping effect of the barrier is *** a speed of 180 km/h,an amplitude of 1.5 m after the barrier is found to be 48.6%lower than that before the *** decreases by 24.2%at 36 km/h and by 38.1%at 108 km/h.

关键词： vibration reduction traffic loads test barrier concrete canvas

Study of probability integration method parameter inversion by the genetic algorithm

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International Journal of Mining Science and Technology 2017年第6期27卷 1073-1079页

作者： Li Peixian Peng Di Tan Zhixiang Deng Kazhong college of Geoscience and surveying Engineering China University of Mining and Technology (Beijing) School of Environment Science and Spatial Informatics China University of Mining and Technology

In order to obtain accurate probability integration method(PIM) parameters for surface movement of multi-panel mining, a genetic algorithm(GA) was used to optimize the parameters. As the measured surface movement is affected by more than one mining panel, traditional PIM parameter inversion model is difficult to ensure the reliability of the results due to the complexity of rock movement. With crossover,mutation and selection operators, GA can perform a global optimization search and has high computation efficiency. Compared with the pattern search algorithm, the fitness function can avoid falling into local minima traps. GA reduces the risk of local minima traps which improves the accuracy and reliability with the mutation mechanism. Application at Xuehu colliery shows that GA can be used to inverse the PIM parameters for multi-panel surface movement observation, and reliable results can be obtained. The research provides a new way for back-analysis of PIM parameters for mining subsidence under complex conditions.

关键词： Probability integration method GA Mining subsidence Parameter inversion Multiobjective optimization