无地面控制点卫星摄影测量

阐述了无地面控制点卫星摄影测量的难点,简要介绍了二线阵CCD影像和三线阵CCD影像卫星摄影测量的精度 ,最后介绍了LMCCD相机用于无地面控制卫星摄影测量的可行性.     

无地面控制点卫星摄影测量

阐述了无地面控制点卫星摄影测量的难点,简要介绍了二线阵CCD影像和三线阵CCD影像卫星摄影测量的精度,最后介绍了LMCCD相机用于无地面控制卫星摄影测量的可行性.     

Determination of volumetric changes at an underground stone mine: a photogrammetry case study

Photogrammetry, as a tool for monitoring underground mine deformation, is an alternative to traditional point measurement devices, and may be capable of accurate measurements in situations where technologies such as laser scanning are unsuited, undesired, or cost-prohibitive. An underground limestone mine in Ohio is used as a test case for monitoring of structurally unstable pillars. Seven pillars were photographed over in a 63 day period, punctuated by four visits. Using photogrammetry, point clouds of the mine geometry were obtained and triangulation surfaces were generated to determine volumes of change over time. Pillar spalling in the range of 0.29–4.03 m³ of rock on individual rib faces was detected. Isolated incidents of rock expansion prior to failure, and the isolated failure of a weak shale band were also observed. Much of the pillars remained unchanged during the monitoring period, which is indicative of proper alignment in the triangulated surfaces. The photographs of some ribs were of either too poor quality or had insufficient overlap, and were not included. However, photogrammetry was successfully applied to multiple ribs in quantifying the pillar geometry change over time.     

A robust approach to identify roof bolts in 3D point cloud data captured from a mobile laser scanner

Roof bolts such as rock bolts and cable bolts provide structural support in underground mines. Frequent assessment of these support structures is critical to maintain roof stability and minimise safety risks in underground environments. This study proposes a robust workflow to classify roof bolts in 3 D point cloud data and to generate maps of roof bolt density and spacing. The workflow was evaluated for identifying roof bolts in an underground coal mine with suboptimal lighting and global navigation satellite system(GNSS) signals not available. The approach is based on supervised classification using the multi-scale Canupo classifier coupled with a random sample consensus(RANSAC) shape detection algorithm to provide robust roof bolt identification. The issue of sparseness in point cloud data has been addressed through upsampling by using a moving least squares method. The accuracy of roof bolt identification was measured by correct identification of roof bolts(true positives), unidentified roof bolts(false negatives), and falsely identified roof bolts(false positives) using correctness, completeness, and quality metrics. The proposed workflow achieved correct identification of 89.27% of the roof bolts present in the test area. However, considering the false positives and false negatives, the overall quality metric was reduced to 78.54%.     

Simulation Study and Probe on UWB Wireless Communication in Underground Coal Mine

1 Introduction Ultra Wide Band (UWB) communication is the technology that transmits signals by using nanosecond pulses. Its characteristics include 1) a high data rate; 2) low power dissipation; 3) a strong anti-multipath fading ability; 4) a simple structured, small bulk, low cost and high sensitive, portable and wireless system and 5) low interference with the existing narrowband communication system. It has been the subject of general interest about short distance wireless communication a…     

射影空间及在结构应变数字摄影测量中应用

射影空间中,数字摄影测量基本模型具有线性特性,避免了欧氏空间迭代运算,解决了ＣＣＤ内方位素不稳定对于高精度、实时数字摄影测量在结构测试中应用影响。本文介绍了射影空间及基本概念,并给出结构应变数字摄影测量模型及特点。     

井下7″级导线及四等水准控制网的建立

综合采用GPS、磁悬浮陀螺全站仪、水准仪以及全站仪等仪器设备,进行高精度矿山三维控制网建立。以某矿区现场实践为例,系统介绍建立井下7″级导线及四等水准控制网的主要步骤及其主要技术指标,包括:地表E级GPS网的建立、井下7″级导线测量、四等水准测量和陀螺定向,以期为类似矿区控制网的建立,提供有效的理论和实践依据。     

Design of a water curtain to reduce accumulations of float coal dust in longwall returns

Accumulation of float coal dust(FCD) in underground mines is an explosion hazard that affects all underground coal mine workers. While this hazard is addressed by the application of rock dust, inadequate rock dusting practices can leave miners exposed to an explosion risk. Researchers at the National Institute for Occupational Safety and Health(NIOSH) have focused on developing a water curtain that removes FCD from the airstream, thereby reducing the buildup of FCD in mine airways. In this study,the number and spacing of the active sprays in the water curtain were varied to determine the optimal configuration to obtain peak knockdown efficiency(KE) while minimizing water consumption.     

地空时间域电磁系统在陕西神木地区煤矿采空区勘查中的应用

为实现陕西神木地区哈拉沟煤矿周边小煤矿采空区的精确定位,采用地空时间域电磁系统在哈拉沟煤矿三盘区附近原小煤矿可能开采范围开展勘查工作。利用电源车集成的大功率地面发射系统,搭配基于旋翼无人机的单分量地空电磁信号接收系统,共采集23条测线的电磁数据。经数据处理后,得到勘查区内地下视电阻率与视深度的高分辨率成像剖面,结合已知钻孔资料综合分析,推测勘查区对应地下煤层位置的低阻带是由煤层积水采空区造成,据此共圈定了8处疑似积水采空区,其中5处为相对低阻异常区域,分布于勘查区中南部、中部以及东北部区域。本次探测工作验证了地空时间域电磁系统在煤矿采空区勘查中的有效性,能够为工作面合理布置和采空区治理等提供可靠的地质信息。     

一种改进的煤矿井下无线传感器质心定位算法

频繁的煤矿井下事故要求无线传感器网络能够更精确的对井下人员进行定位。利用修正加权质心算法进行定位存在较大的误差,针对该问题,在修正加权质心算法的基础上提出了一种改进的煤矿井下无线传感器质心定位算法,该算法将修正加权质心算法得到的质心作为新的锚节点,并通过多次选择、运行形成新的锚节点和质心的方法进行定位。仿真结果表明:不同的巷道宽度下,改变修正系数a的值就可以得到最佳的定位效果,同时可以通过仿真实验得到最佳定位效果下的修正系数a的值,从而使定位精度达到最好。通过比较两种算法的平均定位误差得到改进的煤矿井下质心定位算法在三种巷道宽度下分别将定位误差平均降低了0.792 6m,0.636 2 m,0.598 9 m。     

Fundamentals of modern ground control management in Australian underground coal mines

Underground coal mining is inherently hazardous, with uncontrolled ground failure regarded as one of only several critical risks for multiple fatality events. Development, implementation and management of overarching systems and procedures for maintaining strata control is an important step to mitigating the impact of ground failure hazards at a mine site operational level. This paper summarised the typical pro-active ground control management system(PGCMS) implemented in various Australian underground coal mines. Australia produces approximately 100 million tonnes a year of metallurgical and thermal coal from approximately 30 of the world's safest longwall mines operating in New South Wales and Queensland. The increased longwall productivity required to achieve both high levels of safety and profitability, places significant emphasis on the reliability of pro-active ground control management for longwall mining operations. Increased depths, adverse geological conditions, elevated variable stress regimes and weaker ground conditions, coupled with an industry wide need for increased development rates continue to make ground control management challenging. Ground control management is not only about ground support and pillar design though but also a structured process that requires a coordinated effort from all levels of the workforce to both minimise the occurrence of adverse geotechnical events and mitigate the potential risks when they do occur. The PGCMS presented in this paper is proven to provide both a safer and more productive mine environment through minimisation of unplanned delays. The critical elements of the method are presented in detail and demonstrate the utility and value of a ground control management system that has potential for implementation in underground coal mining globally.     

Application of coal mine roof rating in Chinese coal mines

The coal mine roof rating(CMRR) is a measure of roof quality or structure competency for bedded roof types typically of underground coal mines. The CMRR has been used widely in the US, South Africa,Canada and Australia. In order to investigate the application of the CMRR system in Chinese coal mines,two coal mines in China located in Panjiang Coal Field in Guizhou Province were investigated. Field data were collected which is required to calculate the CMRR value based on underground exposure. The CMRR values of 11 locations in two coal mines were calculated. The investigations demonstrated that the chance of mine roof failure is very low if the CMRR value is more than 50, given adequate support is installed in mine. It was found that the CMRR guideline are useful to preliminarily investigate stability in Panjiang Coal Field mines.     

从安全心理学角度探析新型安全矿井的创建

从安全心理学角度分析了煤矿井下安全影响因素：缺乏安全生产技术与经验、不安全行为心理和生理因素及人为失误.提出可采用改变培训考核方式、进行心理辅导、增加视觉和听觉两方面的信号刺激,以及改善井下环境尤其是照明环境等方法,解决出现人的不安全行为的问题,以创建新型安全矿井.     

瞬变电磁法在矿井水害治理工作中的应用

平煤集团七矿属大水矿井,每年仅排水一项就耗资巨大．给煤矿的经济发展和安全生产带来了极大的风险。为了彻底治理矿井水害,七矿采用瞬变电磁勘探技术．查明了地表水涌入矿井的三条通道,划出了L6、L7灰岩的岩溶裂隙富水区及其二者的水力联系,从而有的放矢地实施帷幕注浆截流治水工程。七矿的注浆工程实践充分验证了瞬变电磁勘探成果的准确性。     

A semi-quantitative coal burst risk classification system

Safety is the highest priority in the mining industry as underground mining in particular poses high safety risks to its workers. In underground coal mines, coal bursts are one of the most catastrophic hazards, which involves sudden and violent dynamic coal mass failure with rapid ejection of the broken material into the mine workings. Despite decades of research, the contributing mechanisms of coal bursts are still not completely understood. Hence, it remains challenging to forecast coal bursts and quantify their likelihood of occurrence. However, a range of geological and geotechnical factors are associated with coal bursts and can increase the coal burst proneness. This paper introduces a semi-quantitative coal burst risk classification system, namely, BurstRisk. Based on back-analysis of case histories from Australia, China and the United States, BurstRisk classifies the coal burst risk into three categories:low, medium and high risk. In addition, it allows mining engineers to modify the weighting of the selected factors based on specific conditions. The risk classification charts introduced are for both longwall retreat and development sections of long-wall mining operations. This paper also provides a set of risk management strategies and control measures for effective coal burst mitigation.     

煤与瓦斯共采技术的研究现状及其应用发展

论述了煤与瓦斯共采技术的重要性及其对煤矿绿色开采的意义，介绍了煤与瓦斯共采技术的研究现状及面临的新问题，并阐明了其理论依据，分析了煤与瓦斯共采在煤矿井下的成功经验，并举例说明了井下瓦斯抽放与地面煤层气开发有机结合的重要性，最后指出了煤与瓦斯共采应注意的问题以及今后的研究方向。     

地空频率域电磁系统在小煤窑勘查中的应用

为实现金谷煤矿小煤窑采掘边界圈定，采用地空频率域电磁系统开展小煤窑采空积水区的勘查试验工作。实际勘探中设计124条南北方向测线，利用无人机搭载探测天线进行电磁数据的连续采集。通过数据处理与解释，获得了测区内地下50~300 m范围内的视电阻率剖面。根据相对低阻异常的分布情况，圈围出两个煤窑采空积水区疑似位置。经过与实际煤层采掘资料对比，圈定的1处低阻异常区域下方存在高度充水的采空区。研究结果证明了地空频率域电磁系统在小煤窑勘查工作中的可行性及有效性。     

全数字化航测成图精度分析

结合生产实践 ,从影响成图精度的几种因素的估算方法入手 ,比较分析了全数字化测图仪器同模拟测图仪器之间的精度差别 .由误差分析和检测结果显示出全数字摄影测量系统仪器比模拟测图仪器的精度高 ,对今后航空摄影测量、航测外业等一系列工作方案的制定及航测经济工作预算有一定的参考价值     

基于GPS差分技术的无控制点或少控制点航测精度分析

主要介绍了通过对GPS差分数据进行无控制点或少控制点的内业空三解算结果的分析得出,基于GPS差分技术的无控制或少控制航空摄影测量的精度完全可以满足航摄测图的精度要求。     

The future of underground spatial planning and the resulting potential risks from the point of view of mining subsidence engineering

The topic of ground movements in Germany has been studied extensively in the past, especially in the field of active mines. The active hard coal mines in Germany were finally shut down in 2018 and lignite mining is expected to take place only until 2038. The so-called long-term liabilities of the mine operators in Germany include, among other things, the long-term guarantee of stability and thus the monitoring of ground motion. So far, the economic use of underground mining in Germany was mainly the supply of raw materials. In the future, the underground storage of compressed air, methane or hydrogen will play an important role in renewable energy supply and climate change. Therefore, the underground storage space will become more important and the spatial planning is essential to ensure availability of safe underground openings for the various options of environmentally friendly energy storage. However, this renewed usage of underground openings may also bring new and sometimes unknown challenges of geomechanical influence. The aftermath of hard coal and lignite mining will be an increasing challenge in mining subsidence engineering. On the other hand, new possibilities due to underground spatial planning may lead to subsidence and/or heaving of the upper surface.