Journal of China University of Mining and Technology最新文献_第10页

Ash melting behavior by Fourier transform infrared spectroscopy 用傅里叶变换红外光谱分析灰渣熔化行为

Journal of China University of Mining and Technology Pub Date : 2008-06-01 DOI: 10.1016/S1006-1266(08)60052-8

Han-xu LI , Xiao-sheng QIU , Yong-xin TANG

引用次数: 9

Study on pick arrangement of shearer drum based on load fluctuation 基于负载波动的采煤机滚筒截齿布置研究

Journal of China University of Mining and Technology Pub Date : 2008-06-01 DOI: 10.1016/S1006-1266(08)60065-6

Chang-long DU , Song-yong LIU , Xin-xia CUI , Ti-jian LI

{"title":"Study on pick arrangement of shearer drum based on load fluctuation","authors":"Chang-long DU , Song-yong LIU , Xin-xia CUI , Ti-jian LI","doi":"10.1016/S1006-1266(08)60065-6","DOIUrl":"10.1016/S1006-1266(08)60065-6","url":null,"abstract":"<div><p>According to the coal or rock cutting theory, a mechanical model and computing formula for a pick and the drum load fluctuation model were established in order to obtain relationships between pick arrangements and drum fluctuation loads, drum rotary speeds and haulage speeds. Based on a minimum load fluctuation, an optimal mathematical model was established for drum pick arrangements. The effects of pick arrangements (including punnett square, sequence, aberrance I and II) on the drum load fluctuation coefficient are discussed. The relationships between the pick arrangements of the drum with different start vanes and the cutting load fluctuation coefficient, the drum rotary speed and haulage speed were also studied. The results indicate that the punnett square arrangement has a smaller cutting load fluctuation coefficient than other forms of arrangement and the drum with the 4-start vanes has the smallest coefficient. The drum rotary speed and haulage speed are affected not only by pick arrangements, but also by the number of vanes.</p></div>","PeriodicalId":15315,"journal":{"name":"Journal of China University of Mining and Technology","volume":"18 2","pages":"Pages 305-310"},"PeriodicalIF":0.0,"publicationDate":"2008-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1006-1266(08)60065-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77516271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 27

EMD-based GPS baseline solution and validation test 基于emd的GPS基线解决方案及验证测试

Journal of China University of Mining and Technology Pub Date : 2008-06-01 DOI: 10.1016/S1006-1266(08)60060-7

Jian WANG , Jing-xiang GAO , Jin-ling WANG , Chang-hui XU

{"title":"EMD-based GPS baseline solution and validation test","authors":"Jian WANG , Jing-xiang GAO , Jin-ling WANG , Chang-hui XU","doi":"10.1016/S1006-1266(08)60060-7","DOIUrl":"10.1016/S1006-1266(08)60060-7","url":null,"abstract":"<div><p>A GPS baseline solution model is presented, based on the Empirical Mode Decomposition (EMD), which has the advantage of eliminating the error effects outside the model. The EMD technique is a new signal processing method for non-linear time series, which decomposes a time series into a finite and often small number of Intrinsic Mode Functions (IMFs). The decomposition procedure is adaptive and data-driven which is suitable for non-linear data series analysis. A multi-scale decomposition and reconstruction architecture is defined on the basis of the EMD theory and the error mitigation model is demonstrated as well. A standard of the scale selection for the elimination of errors, outside the model, was given in terms of the mean of the accumulated standardized modes. Thereafter, the scheme of the GPS baseline solution based on the EMD is suggested. The float solution residuals of the Double-Difference (DD) observation equation are used to extract the errors outside the model applied to modify the GPS DD measurements. Then the float solution was given again and the fixed solution was obtained by a Lambda algorithm. Three schemes are designed to test the proposed model and the experimental results show that the proposed model dramatically improves the reliability of ambiguity resolution after the elimination of errors outside the model.</p></div>","PeriodicalId":15315,"journal":{"name":"Journal of China University of Mining and Technology","volume":"18 2","pages":"Pages 283-287"},"PeriodicalIF":0.0,"publicationDate":"2008-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1006-1266(08)60060-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77956678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 11

Physical simulation of urban rainfall infiltration 城市降雨入渗的物理模拟

Journal of China University of Mining and Technology Pub Date : 2008-06-01 DOI: 10.1016/S1006-1266(08)60062-0

Jie LI, Bing ZENG, Yan-xia WANG, Lei SHEN

引用次数: 3

Zonal disintegration phenomenon in rock mass surrounding deep tunnels 深埋隧洞围岩分区崩解现象

Journal of China University of Mining and Technology Pub Date : 2008-06-01 DOI: 10.1016/S1006-1266(08)60040-1

Hao WU, Qin FANG, Zhi-kun GUO

{"title":"Zonal disintegration phenomenon in rock mass surrounding deep tunnels","authors":"Hao WU, Qin FANG, Zhi-kun GUO","doi":"10.1016/S1006-1266(08)60040-1","DOIUrl":"10.1016/S1006-1266(08)60040-1","url":null,"abstract":"<div><p>Zonal disintegration is a typical static phenomenon of deep rock masses. It has been defined as alternating regions of fractured and relatively intact rock mass that appear around or in front of the working stope during excavation of a deep tunnel. Zonal disintegration phenomenon was successfully demonstrated in the laboratory with 3D tests on analogous gypsum models, two circular cracked zones were observed in the test. The linear Mohr-Coulomb yield criterion was used with a constitutive model that showed linear softening and ideal residual plastic to analyze the elasto-plastic field of the enclosing rock mass around a deep tunnel. The results show that tunneling causes a maximum stress zone to appear between an elastic and plastic zone in the surrounding rock. The zonal disintegration phenomenon is analyzed by considering the stress-strain state of the rock mass in the vicinity of the maximum stress zone. Creep instability failure of the rock due to the development of the plastic zone, and transfer of the maximum stress zone into the rock mass, are the cause of zonal disintegration. An analytical criterion for the critical depth at which zonal disintegration can occur is derived. This depth depends mainly on the character and stress concentration coefficient of the rock mass.</p></div>","PeriodicalId":15315,"journal":{"name":"Journal of China University of Mining and Technology","volume":"18 2","pages":"Pages 187-193"},"PeriodicalIF":0.0,"publicationDate":"2008-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1006-1266(08)60040-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91188125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 15

Effect of ground stress on hydraulic fracturing of methane well 地应力对甲烷井水力压裂的影响

Journal of China University of Mining and Technology Pub Date : 2008-06-01 DOI: 10.1016/S1006-1266(08)60043-7

Chun-zhi DU, Xian-biao MAO, Xie-xing MIAO, Pen WANG

{"title":"Effect of ground stress on hydraulic fracturing of methane well","authors":"Chun-zhi DU, Xian-biao MAO, Xie-xing MIAO, Pen WANG","doi":"10.1016/S1006-1266(08)60043-7","DOIUrl":"10.1016/S1006-1266(08)60043-7","url":null,"abstract":"<div><p>Most of the coal reservoirs in China are of low-permeability, so hydraulic fracturing is widely used to improve the permeability in the extraction of gas by ground drilling. The ground stress around the well was analyzed by using theory of elasticity. The pressure when the well fractured is formulated and the effect of ground stress on pressure is discussed. The effect of ground-stress-differences on hydraulic fracturing was analyzed by using the numerical software RFPA<sup>2D</sup>-Flow in reference to the tectonic stress in Jincheng coal area. The results show that: 1) the position where initial fracture appears is random and fracture branches emerge when the fractures expand if ground stresses in any two directions within a horizontal plane are equal; 2) otherwise, the fractures expand in general along the direction of maximum ground stress and the critical pressure decreases with increasing ground-stress-differences and 3) the preferred well-disposition pattern is diamond shaped. The preferred well spacing is 250 m × 300 m. This study can provide a reference for the design of wells.</p></div>","PeriodicalId":15315,"journal":{"name":"Journal of China University of Mining and Technology","volume":"18 2","pages":"Pages 204-209"},"PeriodicalIF":0.0,"publicationDate":"2008-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1006-1266(08)60043-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88852208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

Monitoring dispatch information system of trucks and shovels in an open pit based on GIS/GPS/GPRS 基于GIS/GPS/GPRS的露天矿车铲监控调度信息系统

Journal of China University of Mining and Technology Pub Date : 2008-06-01 DOI: 10.1016/S1006-1266(08)60061-9

Qing-hua GU , Cai-wu LU , Fa-ben LI , Chang-yong WAN

引用次数: 35

Numerical simulation for determining three zones in the goaf at a fully-mechanized coal face 综采工作面采空区三带确定的数值模拟

Journal of China University of Mining and Technology Pub Date : 2008-06-01 DOI: 10.1016/S1006-1266(08)60042-5

Xiao-gang HE , Ren-wei ZHANG , Xiao-dong PEI , Yong SUN , Bo-gen TONG , Hua-shan HUANG

引用次数: 14

Co-integration-based analysis of energy assurance for steady economic growth in China 基于协整的中国经济稳定增长能源保障分析

Journal of China University of Mining and Technology Pub Date : 2008-06-01 DOI: 10.1016/S1006-1266(08)60053-X

Ya-qun HE , Guo-hong LAO , Chris E OSUCH , Wei-ran ZUO , Bao-feng WEN

引用次数: 16

Field experiment for blasting crater 爆破坑的现场试验

Journal of China University of Mining and Technology Pub Date : 2008-06-01 DOI: 10.1016/S1006-1266(08)60047-4

Tu-qiang YE

引用次数: 8