IETM在舰船机电设备信息化保障中的应用

舰船机电设备的信息化保障是部队战斗力的关键因素之一。传统的设备维修保障方式已无法满足部队信息化的要求,通过交互式电子技术的运用,建立实时交互的舰船机电设备管理平台,可提高机电设备维修保障的信息化水平和效率。针对舰船机电设备发展趋势及维修管理的要求,采用VB语言编制了舰船机电设备交互式电子手册,并对研制过程中的主要技术问题和系统进行了介绍,对于编制设备技术手册和舰船完工文件具有指导作用。     

烟台某工程循环水取、排水工程压水试验

为确定烟台某工程地基基岩的渗透特性,阐述水上岩体压水试验的主要操作过程、试验数据处理和试验结果分析评价方法．测定区域内的各岩层的透水率和渗透系数,给出不同风化程度岩层的渗透性评价,为设计提供防渗设计所需参数。     

气体灭火系统受干扰的原因及防范措施

介绍气体灭火系统受外界干扰导致误喷放的情况,从探测器、控制器和线路方面,探讨形成干扰的主要类型和原因,结合实际工程中的应用情况,有针对性地提出防范措施.     

摆式列车受电弓垂向振动主动控制

建立了摆式列车机电耦合动力学模型、受电弓线性和非线性动力学模型及接触网有限元模型和静态接触刚度模型,组成摆式列车-受电弓-接触网耦合动力学模型,分别设计了P和H∞鲁棒控制器,应用数值仿真方法,研究了摆式列车直线和曲线通过时两种控制器对摆式列车受电弓垂向主动控制的效果。结果表明受电弓若无垂向控制,其弓网接触压力波动较大;P和H∞鲁棒控制均能减小弓网接触压力的波动;控制延时对P控制比对H∞鲁棒控制的影响大;是否考虑接触网的振动对接触压力影响较大,对控制效果影响不大。这说明摆式列车受电弓垂向主动控制能明显改善弓网接触压力波动;H∞鲁棒控制比P控制效果更好;接触网的静态接触刚度模型可用于受电弓主动控制的定性分析。     

On Safety in Dismantling Temporary Strut of Super-large Tunnels with Double-layer Primary Support北大核心CSCD

More and more multiple-track tunnels and super-large section tunnels have been built, and disman- tling of temporary strut is a weak point of the whole structure during force transfer when the secondary lining is con- structed. It is significant to guarantee structure safety during dismantling of temporary strut. Little systematic re- search on safety in dismantling of temporary strut of the super-large section tunnel with double-layer primary support has been conducted, so the internal force and security of the two-layer primary support of the Xinkaotang tunnel were analyzed by a numerical analysis and site measurement, and it proves the effect of two-layer primary support on the safety during strut dismantling. The research results indicate that: (1) with constant support thickness and one-time longitudinal dismantling length, the safety factor of secondary primary support is larger than that of the first primary support, and the safety factor of the first primary support is larger than that of the single-layer primary support. Change range of safety factor for the first primary support is smaller than that of the single-layer primary support, and the safe factor for the single-layer primary support is smaller than that of the secondary primary support; (2) with the same support pattern, the safety factors increase firstly and then decrease with an increase of the onetime dismantling length. The calculated results of various cases show that the reasonable one-time dismantling length for this project is about 9 m. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

Effect of Explosion in a Gas Pipeline Compartment of a Utility Tunnel on Neighboring Metro Tunnels北大核心CSCD

In this paper the numerical simulation analysis of the effect of explosion in the gas pipeline compartment of a utility tunnel on neighboring metro tunnels was conducted using the software AUTODYN. The results show that the TNT equivalent in a fireproof partition with length of 200 m is 41.6 kg when the gas concentration in the gas pipeline compartment reaches 10%; the blast wave has much effect on the crown and arch waist of the round metro tunnel and it’s necessary to take some protective measures in both areas; when the surrounding soil is sand, the utili- ty tunnel is above the round metro tunnel and their alignments are in the same direction, the greater the vertical spacing between the utility tunnel and the metro tunnel, the smaller the effect of the blast wave on the metro tunnel; when the vertical spacing is 7.2 m, the maximum dynamic tensile stress is 1.86 MPa (including the static stress value of 1 MPa in the tunnel segment) and it is slightly smaller than the designed tensile strength of metro tunnel (about 1.89 MPa). The maximum vibration velocity and the maximum displacement meet the structural stability require- ments, so it is suggested the vertical spacing between the utility tunnel and metro tunnel shall not be less than 7.2 m. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

Structural Optimization and Strength Analysis of the Lifting Arm of a Wet Shotcrete Spraying Unit北大核心CSCD

Wet shotcrete spraying units are widely used in underground engineering, for railways, highways, water conservancy and hydropower stations, municipal works, mining and military and other industries. Structural analysis and mechanical behavior optimization are conducted regarding the lifting arm of a TKJ series shotcrete spraying unit, and optimization of the hinge point position and working scope of the lifting arm is realized. The optimal layout scheme for the hinge force is given based on the Monte Carlo method, the hinge force of the lifting arm is improved for the mean and maximum values, and the maximum and average hinge force of the lifting cylinder decrease by 23.14% and 7.70%, respectively, compared with that of the original scheme. The static strength is checked using Ansys-Workbench for the optimized scheme, and the results show that the optimized scheme has a larger safety re-serve and that the structural design is more reasonable than the original scheme. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

A Study of Prevention Techniques for Tunnel Lining Defects北大核心CSCD

Defects of tunnel lining, such as inadequate thickness, voids, cracks, rock falling and water leakage etc., endanger the safety of railway tunnel operation. Based on the site construction, an analysis of the reasons for lining defects was conducted; technical measures against lining defects were proposed and tests were carried out at site. The results show that these measures are reliable and effective, and the purposes of prevention and treatment are re⁃ alized. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

舰船中压直流综合电力推进系统稳态分析研究

本文对舰船中压直流综合电力推进系统进行稳态分析。首先,根据舰船中压直流综合电力系统基本特点,选定直流分层前推回代法作为基本方法加以改进;同时,提出了适用于该方法的支路计算等效模型,并将上述思想进行程序实现。通过算例分析结果可知,论文所提出的基于直流分层前推回代法的潮流计算方法,能够适用于舰船中压直流综合电力推进系统。     

Modeling the interactions between car and bicycle in heterogeneous traffic

In this paper, a new cellular automata model is proposed to simulate the car and bicycle heterogeneous traffic on urban road. To capture the complex interactions between these two types of vehicles, a novel occupancy rule is adopted in the proposed model to consider the variable lateral distances of mixed vehicular traffic. Based on massive simulations, microscopic fundamental diagrams under different bicycle densities are devised. With these, the bicycle's spilling behavior is then investigated and discussed. In order to reflect the interference of a bicycle on a car, the interference transformation from friction state to block state is modeled explicitly. Finally, different simulation results under different occupancy rules indicate that the constant and fixed occupancy rule adopted in the previous studies might lead to overestimation of car flux in the heterogeneous traffic flows with different bicycle densities. Copyright © 2013 John Wiley & Sons, Ltd.