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New Progress on the Coal Fines Affecting the Development of Coalbed Methane

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Acta Geologica Sinica(English Edition) 2018年第5期92卷 2060-2062页

作者： WEI Yingchun LI Chao CAO Daiyong ZHANG Aoxiang WANG Anmin XIANG Xinxuan college of Geoscience & surveying Engineering China University of Mining & Technology

Objective The production of coal fines is very common in the development of coalbed methane（CBM）in the eastern margin of the Ordos Basin,China.A large amount of produced coal fines seriously affect the productivity of CBM wells（Wei Yingchun et al.,2013）.Therefore,the production problems of CBM wells caused by coal fines have attracted extensive attention.

关键词： New Progress on the Coal Fines Affecting the Development of Coalbed Methane GS CBM

Altimetric Algorithm and Errors of Ocean Altimetry Using GNSS Reflection Signals

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China Ocean Engineering 2015年第6期29卷 933-944页

作者：郭金运王书阳刘新王建波常晓涛 college of Geodesy and Geomatics Shandong University of Science and Technology Key Laboratory of surveying and Mapping Technology on Island and Reef of NASMG Satellite surveying and Mapping Application Center of NASMG

As a new remote sensing technology, the global navigation satellite system（GNSS） reflection signals can be used to collect the information of ocean surface wind, surface roughness and sea surface height. Ocean altimetry based on GNSS reflection technique is of low cost and it is easy to obtain large amounts of data thanks to the global navigation satellite constellation. We can estimate the sea surface height as well as the position of the specular reflection point. This paper focuses on the study of the algorithm to determine the specular reflection point and altimetry equations to estimate the sea surface height over the reflection region. We derive the error equation of sea surface height based on the error propagation theory. Effects of the Doppler shift and the size of the glistening zone on the altimetry are discussed and analyzed at the same time. Finally, we calculate the sea surface height based on the simulated GNSS data within the whole day and verify the sea surface height errors according to the satellite elevation angles. The results show that the sea surface height can reach the precision of 6 cm for elevation angles of 55° to 90°, and the theoretical error and the calculated error are in good agreement.

关键词： GNSS refection technique sea surface height specular reflection point error propagation ocean altimetry

Land use scenario simulation of mountainous districts based on Dinamica EGO model

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Journal of Mountain Science 2020年第2期17卷 289-303页

作者： CHENG Lin-lin LIU Mei ZHAN Jia-qi college of Geoscience and surveying Engineering China University of Mining and Technology (Beijing)

Mountainous area makes up 22% of global land, and rational land use in this area is important for sustainable development. Mentougou district has been positioned as an ecological conservation development zone of Beijing and significant land use changes have taken place since 2004. With the combination of GIS and Dinamica EGO(Environment for Geoprocessing Objects) model, the quantitative structure and spatial distribution of land use in Mentougou from 2006 to 2014 are analyzed in this paper. Considering topography has influence on the action mode of driving factors, the research area is divided into two parts based on elevation, mountainous area above 300 m, plain and shallow mountainous area below 300 m. Based on cellular automata theory, the probability of land use change is calculated by Weights of Evidence method and the spatial distribution of land use is simulated by means of two complementary spatial transition functions: Expander and Patcher. Land use pattern of Menougou in 2030 for three kinds of scenarios: trend development, rapid development and ecological protection are simulated. The comparison shows that the trend development scenario is more reasonable based on social, economic and environmental considerations and other scenarios provide a reference for improving irrational land use.

关键词： Land use change Mountainous districts Dinamica EGO model Scenarios simulation Mentougou district

Characteristics of Early Cretaceous wildfires in peat-forming environment, NE China

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Journal of Palaeogeography 2019年第3期8卷 238-250页

作者： Shuai Wang Long-Yi Shao Zhi-Ming Yan Ming-Jian Shi Yun-He Zhang college of Geoscience and surveying Engineering China University of Mining and Technology (Beijing)

Inertinite maceral compositions in coals from the Early Cretaceous Erlian, Hailar, and Sanjiang Basins in NE China are analyzed in order to reveal palaeowildfire events and palaeoclimate variations. Although huminite is the dominant maceral group in the studied basins, the inertinite group, as a byproduct of palaeowildfires, makes up a considerable proportion. Occurrence of inertinite macerals indicates that wildfires were widespread and frequent,and supports the opinion that the Early Cretaceous was a "high-fire" interval. Inertinite contents vary from 0.2% to 85.0%, mostly within the range of 10%–45%, and a model-based calculation suggests that the atmospheric oxygen levels during the Aptian and Albian(Early Cretaceous) were around 24.7% and 25.3% respectively. Frequent fire activity during Early Cretaceous has been previously related to higher atmospheric oxygen concentrations. The inertinite reflectance, ranging from 0.58%Ro to 2.00%Ro, indicates that the palaeowildfire in the Early Cretaceous was dominated by ground fires, partially reaching-surface fires. These results further support that the Cretaceous earliest angiosperms from NE China were growing in elevated O2 conditions compared to the present day.

关键词： Inertinite Coal Wildfire Palaeo-atmospheric oxygen level Angiosperm Early Cretaceous NE China

Route Height Connection Across the Sea by Using the Vertical Deflections and Ellipsoidal Height Data

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China Ocean Engineering 2013年第1期27卷 99-110页

作者：郭金运陈永宁刘新钟世霞麦照秋 college of Geodesy and Geomatics Shandong University of Science and Technology Key Laboratory of surveying and Mapping Technology on Island and Reef of NASMG The 7th Terrestrial surveying Team of NASMG

Distance between the main land and island is so long that it is very difficult to precisely connect the height datum across the sea with the traditional method like the trigonometric leveling, or it is very expensive and takes long time to implement the height transfer with the geopotential technique. We combine the data of GPS surveying, astro-geodesy and EGM2008 to precisely connect the orthometric height across the sea with the improved astronomical leveling method in the paper. The Qiongzhou Strait is selected as the test area for the height connection over the sea. We precisely determine the geodetic latitudes, longitudes, heights and deflections of the vertical for four points on both sides across the strait. Modeled deflections of the vertical along the height connecting routes over the sea are determined with EGM2008 model based on the geodetic positions and heights of the sea segmentation points from DNSC08MSS model. Differences of the measured and modeled deflections of the vertical are calculated at four points on both sides and linearly change along the route. So the deflections of the vertical along the route over the sea can be improved by the linear interpolation model. The results are also in accord with those of trigonometirc levelings. The practical case shows that we can precisely connect the orthometric height across the Qiongzhou Strait to satisfy the requirement of order 3 leveling network of China. The method is very efficient to precisely connect the height datum across the sea along the route up to 80 km.

关键词： height connection across sea deflection of the vertical astro-geodesy orthometric height ellipsoidal height

Digital close-range photogrammetric application to small-scale physical simulation experiment

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中国有色金属学会会刊：英文版 2011年第S3期21卷 681-685页

作者： LI Chun-yi1, CUI Xi-min2, YU Yi-ju3 1. School of surveying and Landing Information Engineering, Henan Polytechnic University, Jiaozuo 454003, China 2. college of Geoscience and surveying Engineering, China University of Mining and Technology, Beijing 100083, China 3. surveying and Mapping Press, Beijing 100045, China School of surveying and Landing Information Engineering Henan Polytechnic University Jiaozuo 454003 China college of Geoscience and surveying Engineering China University of Mining and Technology Beijing 100083 China surveying and Mapping Press Beijing 100045 China

In order to research the possibility of digital close-range photogrammetric surveying in small scale physical simulation experiment, physical model coinciding with engineering practice was constructed based on similar theory. The datum processing method and surveying precision of digital close-range photogrammetric were analyzed. And the function relationship between overburden subsidence factor qr and the ratio z/H of stratum horizon z and mining depth H was researched. The results show that surveying points position mean error along horizontal direction is ±0.131 mm and vertical direction is ±0.192 mm. Therefore, multi-taking station cross direction digital close-range photogrammetric can completely satisfy the precision need of physical simulation experiment. And the empirical formula can be utilized to represent evolution law of stratum subsidence factor.

关键词： close-range photogrammetric physical simulation light-rays adjustment surveying precision subsidence factor

Properties of L-band differential InSAR for monitoring mining-induced subsidence in coalfield of Jining, Northern China

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Journal of Central South University 2014年第4期21卷 1508-1517页

作者：陶秋香刘国林 Geomatics college Shandong University of Science and Technology Key Laboratory of surveying and Mapping Technology on Island and Reef of National Administration of surveying Mapping and Geoinformation

The properties and feasibility of L-band differential InSAR for detecting and monitoring mining-induced subsidence were systematically analyzed and demonstrated. The largest monitored subsidence gradient of 7.9×10-3 and magnitude of 91 cm were firstly derived by theoretical derivation. Then, the stronger phase maintaining capacity and weaker sensitivity to minor land subsidence compared with C-band DInSAR were illustrated by phase simulation of the actual mine subsidence. Finally, the data processing procedure of two-pass DInSAR was further refined to accurately observe subsidence of a coalfield of Jining in Northern China using 7 ALOS PALSAR images. The largest monitored subsidence magnitude of 39.22 cm and other properties were better investigated by testing results interpretation and subsidence analysis, and the absolute difference varying from 0.5 mm to 17.9 mm was obtained by comparison with leveling-measured subsidence. All of results show that L-band DInSAR technique can investigate the location, amount, area and other detailed subsidence information with relatively higher accuracy.

关键词： L-band differential InSAR ALOS PALSAR mine subsidence monitoring

Water distribution extracted from mining subsidence area using Kriging interpolation algorithm

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中国有色金属学会会刊：英文版 2011年第S3期21卷 723-726页

作者： DAI Hua-yang, REN Li-yan, WANG Meng, XUE Hai-bing college of Geosicence and surveying Engineering, China University of Mining & Technology, Beijing 100083, China college of Geosicence and surveying Engineering China University of Mining & Technology Beijing 100083 China

By comprehensively analyzing the data of geology and mining, Kriging algorithm was introduced to analyze the thematic information of geological data, to rapidly extract mining parameters for predicting mining subsidence, and to effectively integrate geomorphology and predict information. As a result, the change information of water body is successfully detected from the prediction of surface subsidence due to mining activity. Analysis shows that the elevation of farmland in the west side of water body will be lower than ever, and the west part farmland will be submerged. However, there is no evidence for impacting the villages. All the information provides a reference for efficiently assessing environmental impact due to mining activity, which can help to govern the subsidence of the area reasonably.

关键词： Kriging interpolation water body mining subsidence prediction parameters data fusion

Real‑time service performances of BDS‑3 and Galileo constellations with a linear satellite clock correction models

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Satellite Navigation 2023年第3期4卷 72-81页

作者： Haojun Li Danzeng Luojie Huimin Ding college of surveying and Geo‑Informatics Tongji UniversityShanghai 200092People’s Republic of China

In order to facilitate high-precision and real-time Precise Point Positioning(PPP),the International GNSS(Global Navigation Satellite System)Service(IGS),BDS-3(BeiDou-3 Navigation Satellite System),and Galileo navigation satellite system(Galileo)have provided real-time satellite clock correction,which is updated at a ***,the frequent updates pose the challenges of increasing the computational burden and compromising the timeliness of these correction *** address this issue,an improved Real-Time Service(RTS)method is developed using an extrapolation algorithm and a linear *** results indicate that a 1 h arc length of the satellite clock correction series is optimal for fitting a linear model of the *** this approach,the 1 h extrapolation results for BDS-3 and Galileo are superior to 0.09 ***,when these model coefficients are transmitted and updated at the intervals of 1,2,5,and 10 min,the corresponding PPP can converge at the *** is evident that these improved RTS methods outperform the current approach with high-frequency interval transmission,as they effectively mitigate the challenges associated with maintaining the timeliness of correction parameters.

关键词： Precise point positioning Satellite clock correction Real-time service