超宽带室内定位精度受非视距传播(Non-Line Of Sight,NLOS)、多径效应、基站布设等因素影响,而这些因素均与基站的布设阵型有关.因此,本文提出一种基于位置精度稀释因子(Positioning Dilution Of Precision,PDOP)、到达时间差(Time Diff...超宽带室内定位精度受非视距传播(Non-Line Of Sight,NLOS)、多径效应、基站布设等因素影响,而这些因素均与基站的布设阵型有关.因此,本文提出一种基于位置精度稀释因子(Positioning Dilution Of Precision,PDOP)、到达时间差(Time Difference Of Arrival,TDOA)测量误差和克拉美劳界的基站布设优化数学模型,可用遗传算法和萤火虫算法等智能算法求解.理论推导和仿真测试表明优化后的基站布设阵型相较于传统的立方体8基站阵型具有更好的平均误差和方差.14.5 m×7.6 m×3 m展厅的实测实验结果表明,经过优化后的基站布设阵型定位精度提高了0.7132 cm,且方差减小了50.6496 cm^(2)具有较高的稳定性.展开更多
Response surface method is used to study the reliability analysis of laterally loaded piles in sloping ground. A development load-displacement （p-y） curve for laterally loaded pile response in sloping ground is used...Response surface method is used to study the reliability analysis of laterally loaded piles in sloping ground. A development load-displacement （p-y） curve for laterally loaded pile response in sloping ground is used to model the pile-soil system, both the pile head displacement and the maximum bending moment of the piles are used as the performance criteria in this study. The reliability analysis method of the laterally loaded pile in sloping ground under the pile head displacement and the maximum bending moment failure modes is proposed, which is in good agreement with the Monte Carlo method. The influences on the probability index of failure by a number of parameters are discussed. It is shown that the variability of pile head displacement increases with the increase in the coefficients of variation of ultimate bearing capacity factor （Npu）, secant elastic modulus at 50%（E50） and level load （H）. A negative correlation between Npu and non-dimensional factor （λ） leads to less spread out probability density function （PDF） of the pile head displacement;in contrast, a positive correlation between Npu andλgives a great variation in the PDF of pile head displacement. As for bearing capacity factor on ground surface （Npo） and λ, both negative and positive correlations between them give a great variation in the PDF of pile head displacement, and a negative correlation will obviously increase the variability of the response.展开更多
文摘超宽带室内定位精度受非视距传播(Non-Line Of Sight,NLOS)、多径效应、基站布设等因素影响,而这些因素均与基站的布设阵型有关.因此,本文提出一种基于位置精度稀释因子(Positioning Dilution Of Precision,PDOP)、到达时间差(Time Difference Of Arrival,TDOA)测量误差和克拉美劳界的基站布设优化数学模型,可用遗传算法和萤火虫算法等智能算法求解.理论推导和仿真测试表明优化后的基站布设阵型相较于传统的立方体8基站阵型具有更好的平均误差和方差.14.5 m×7.6 m×3 m展厅的实测实验结果表明,经过优化后的基站布设阵型定位精度提高了0.7132 cm,且方差减小了50.6496 cm^(2)具有较高的稳定性.
基金Projects(5147847951322403)supported by the National Natural Science Foundation of China+3 种基金Project(2015CX005)supported by Innovation Driven Plan of Central South University,ChinaProject(14JJ4003)supported by Hunan Provincial Natural Science Foundation,ChinaProject(SKLGP2014K008)supported by Opening Fund of State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,ChinaProject(2015CB060200)supported by the National Basic Research Program of China
文摘Response surface method is used to study the reliability analysis of laterally loaded piles in sloping ground. A development load-displacement （p-y） curve for laterally loaded pile response in sloping ground is used to model the pile-soil system, both the pile head displacement and the maximum bending moment of the piles are used as the performance criteria in this study. The reliability analysis method of the laterally loaded pile in sloping ground under the pile head displacement and the maximum bending moment failure modes is proposed, which is in good agreement with the Monte Carlo method. The influences on the probability index of failure by a number of parameters are discussed. It is shown that the variability of pile head displacement increases with the increase in the coefficients of variation of ultimate bearing capacity factor （Npu）, secant elastic modulus at 50%（E50） and level load （H）. A negative correlation between Npu and non-dimensional factor （λ） leads to less spread out probability density function （PDF） of the pile head displacement;in contrast, a positive correlation between Npu andλgives a great variation in the PDF of pile head displacement. As for bearing capacity factor on ground surface （Npo） and λ, both negative and positive correlations between them give a great variation in the PDF of pile head displacement, and a negative correlation will obviously increase the variability of the response.
