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断层是影响隧道稳定的不良地质现象,EH4电磁测深法工作频率在10Hz~100kHz,其探测深度大,本文应用EH4电磁测深法探测埋深不同的隧道,断层勘察效果较好,探明了断层的宽度、倾向、倾角等地质要素,其探测结果可指导隧道设计并对开挖过程中的灾害进行预防和提前处理。 相似文献
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本文应用瞬变电磁仪对贵州省水盘高速大营脚隧道进行超前地质探测,准确预报其岩溶、富水地质段,并结合隧道内掌子面地质观察,对隧道初期支护参数提出修正建议,确保了隧道的安全施工。 相似文献
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Zhang K.-L.Liu X.-J.Zhang W.-L. 《铁道工程学报》2014,(9):102-107
Research purposes: Based on Maxwell equations and T-type equivalent circuit of linear induction motor, we analyze the electromagnetic thrust output of a double-sided linear induction motor in the case of edge effect, and use the finite element method and simulation to test the effectiveness of the theoretical calculation. We further derivate the mathematical expressions of a double-sided linear induction motor, build the simulation model by parameter design, and experimentally analyze the slip frequency control thrust output in conditions of different operating. Through analysis of the output characteristics of the electromagnetic force, optimal control of constant current slip frequency is achieved. Research conclusions: (1) We calculate various mechanical properties of a bilateral linear induction motor through its mathematical model and equivalent circuit, and derive the corrected coefficients of the horizontal and vertical edge effect. When the motor runs at a high speed, the edge effect has little influence on the output of the electromagnetic force. (2) We use the finite element computer software to establish the simulation model of a bilateral linear induction motor, and compare the theoretical calculation and simulation data: the simulation results are consistent with theoretical calculation, thus ensuring the validity of the mathematical model. (3) We simulate and analyze the influence of slip frequency, speed, suspension air gap, and length of the mover on electromagnetic force. At different speeds, properly adjusting the slip frequency can increase the output of electromagnetic force. For low speed, the optimal slip frequency is near 2 Hz; for high speed, the optimal slip frequency is between 4.0 Hz and 6.0 Hz. When satisfying the motor's rated condition, the optimal control of electromagnetic force is achieved. (4) The research result of double-sided linear induction motor can provide important implications for the electromagnetic launch system of an aircraft carrier. 相似文献
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随着汽车电气化智能化的需求越来越高,EMC已经成为0EM生产厂家无法回避的关键问题之一。有必要从零部件的性能方面就加以严格控制,也必须对标准及测试方法有一个完整的了解。 相似文献
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Introduction Chinese traditional medicine database is huge andcovers a large amount of valuable knowledge. Thedatabase technical development has solved the prob-lem of efficiency of data saving and searching in usingthe medicine database. However, diversity of the datatypes and hugeness of the data amount are far beyondpeoples intellect. Sometimes, the large database be-come the“data grave”and causes a phenomenon of“data rich but information poor”.Using the modern information technologies… 相似文献
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分析电气化铁道贯通地线引起的地电位升,建立贯通地线入地电流在周围引起地电位升的模型,推导贯通地线电流引起的地电位升的公式。根据不同的土壤电阻率和贯通地线上电流的大小,计算与贯通地线不同距离时的地电位升,对地下金属管线的布置及接地点的选取具有一定的参考作用。 相似文献