Results 81 to 90 of about 12,334 (149)
Theory of coal wall spalling and cooperative control by “support-destressing” in 10 m ultra-large mining height working face [PDF]
Coal wall spalling is one of the main factors restricting the safe production of 10 m ultra-large mining height working face.In response to the problem of unclear mechanism of coal wall spalling and difficult control of surrounding rock in the 10 m ultra-
Cundi HAN +7 more
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Key technologies of microbial mining residual coal and CO2-fly ash co-filling in the impacted geological body of coal mining [PDF]
The gob of coal mine is an important area for achieving the goal of “dual carbon” in China. The geological body formed by coal mining, which can enrich coalbed methane and provide substrate and space for later microbial activities and mineralization ...
Lufei WANG +4 more
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Characteristics of pressure relief gas enrichment zones in overlying strata during high-strength mining based on elliptical-parabolic zone theory [PDF]
With the deepening and high-strength development of coal resource mining, gas issues and safety hazards in the mining process become increasingly prominent.
Bin ZHOU +7 more
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基于结构健康监测的大直径球体高层支撑钢结构施工全过程性能评估
Jianzhu Gangjiegou Jinzhan基于结构性态健康监测系统数据，对大直径球体高层支撑钢结构体系进行施工全过程的结构监控。根据结构设计超限情况，进行了不同传感器的测点布设，建立了以应力、应变、倾角位移和温度传感器为基础的结构健康监测系统；结合结构全施工过程模拟分析，对比评价了构件及结构体系在各施工阶段的应力和变形，并分析了球体顶部穹顶结构提升过程中结构的力学性态变化。根据模拟分析结果，结合监测系统采集的实测数据，验证了施工期构件及结构体系的安全性，评价了施工全过程环境温度对结构性能的影响 ...
王毅飞 +4 more
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Innovation and practice of quadrilateral development model for coal resources [PDF]
China’s coal mining technology has undergone many innovations, with continuous improvements in the intensification and modernization levels of coal production.
Feng JU +4 more
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Gaoya dianqi, 2014 中压断路器是电网中重要的电力设备,对其进行状态检测有利于发现潜在隐患。振动检测是一种非侵入的检测方法,振动信号是断路器内部一系列振动事件的响应,包含丰富的断路器机械状态信息,因此,设计开发一套基于振动的断路器状态检测系统是非常有意义的。在构建该系统过程中,考虑了振动传感器的型号与安装位置、设计了信号调理电路、选择了数据采集卡等硬件,同时利用VC++和Lab VIEW开发了数据采集、截取与分析软件,具有友好人机交互界面。在分析方法上,计算振动信号的信息熵向量作为故障诊断特征向量,利用支持向量机实现故障诊断。
潘徽, 宋政湘, 牛博
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Theory and technology of partial backfill non-pillar mining in longwall faces of steeply dipping coal seam [PDF]
The structure and stress environment of the surrounding rock at the longwall mining area in the steeply dipping coal seam are alienated, and the composition factors and disaster modes of the ”support and surrounding rock” system in the working face are ...
Bosheng HU +4 more
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采用GPS/北斗双星同步采集技术的分布式无线高压绝缘带电测试的研究
Gaoya dianqi, 2017 随着智能电网建设和状态检修工作的开展,需要及时掌握电容型设备、避雷器等的绝缘状态。但目前绝缘在线监测、带电检测技术在检测精度、设备可靠性等方面存在不足,并未被电力部门广泛应用。文中研究了基于高精度GPS/北斗双星同步采集和分布式无线便携式带电测试系统,以提高绝缘检测的精度和便捷性。文中介绍了该系统实现的原理,GPS/北斗的PPS秒脉冲直接硬件控制的方式启动Σ-Δ型AD数据采集,和软件流程的时序协同控制,利用改进的迭代—正交算法,极大的降低了相对介损测量误差,提高了数据的重复性与稳定性。对算法的影响 ...
鞠登峰 +6 more
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Dianci bileiqi新能源场站电气预防性试验工作中，集电线路避雷器试验是必做项目之一。但常规试验场地局限性大，耗时长，且避雷器所处位置较高，试验人员操作困难、危险系数大。为解决此问题，对集电线路避雷器试验效率的提高进行研究，并在枣强风电场例行预防性试验中进行了应用，结果表明，完成此次试验节约人工成本约17300元，节约时长约270小时，同时降低了危险系数，避免了事故发生，减少了设备损坏的频率，使原本费时费力的集电线路避雷器试验工作变得安全高效。
吕泽卿
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Guangtongxin yanjiu, 2015 先进的调制技术可以有效地改善光通信系统抵御色散、偏振模和非线性等损伤的能力,是超高速光通信系统中的重要技术。MSK（最小频移键控）是一种恒包络调制技术,具有色散容限较大和能量集中等优点,文章将MSK调制引入PM（偏振复用）系统,提出了一种适应于超高速光通信系统的PM-MSK调制方案。理论分析和数值仿真结果表明,该方案与RZ（归零）和QPSK（正交频移键控）方案相比,具有更好的误码率性能。
李红艳, 沈建华
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