化学灌浆在输水隧洞渗漏处理中的运用

福清市闽江调水工程输水隧洞,原地下水较活跃,后经水泥灌浆,堵住大部分水,但渗漏现象还比较严重,难以靠单一的水泥灌浆彻底堵住渗漏,后经采用PU4水溶性聚氨酯对漏水点进行化学灌浆取得了较好的止水效果。PU4水溶性聚氨酯是一种单组份灌浆材料,其遇水后自行分散、乳化、发泡,立即进行聚合反应,聚合后的固结体有良好的延伸性、弹性及抗渗性,体现了弹性止水和以水止水的双重功能。可供类似工程参考。     

An optimal algorithm for two robots path planning problem on the grid

This paper is a study on the problem of path planning for two robots on a grid. We consider the objective of minimizing the maximum path length which corresponds to minimizing the arrival time of the last robot at its goal position. We propose an optimal algorithm that solves the problem in linear time with respect to the size of the grid. We show that the algorithm is complete; meaning that it is sure to find an optimal solution or report if any does not exist.     

Application of shifted Jacobi pseudospectral method for solving (in)finite-horizon min–max optimal control problems with uncertainty

The difficulty of solving the min–max optimal control problems (M-MOCPs) with uncertainty using generalised Euler–Lagrange equations is caused by the combination of split boundary conditions, nonlinear differential equations and the manner in which the final time is treated. In this investigation, the shifted Jacobi pseudospectral method (SJPM) as a numerical technique for solving two-point boundary value problems (TPBVPs) in M-MOCPs for several boundary states is proposed. At first, a novel framework of approximate solutions which satisfied the split boundary conditions automatically for various boundary states is presented. Then, by applying the generalised Euler–Lagrange equations and expanding the required approximate solutions as elements of shifted Jacobi polynomials, finding a solution of TPBVPs in nonlinear M-MOCPs with uncertainty is reduced to the solution of a system of algebraic equations. Moreover, the Jacobi polynomials are particularly useful for boundary value problems in unbounded domain, which allow us to solve infinite- as well as finite and free final time problems by domain truncation method. Some numerical examples are given to demonstrate the accuracy and efficiency of the proposed method. A comparative study between the proposed method and other existing methods shows that the SJPM is simple and accurate.     

GE Rx7i PLC在热连轧带钢生产线飞剪控制系统中的应用

本文主要介绍GE Rx7i PLC在热连轧带钢生产线飞剪定尺剪切控制系统中的应用,分析飞剪剪切控制原理,推导飞剪剪切方程,对提高飞剪的作业率和带钢质量以及下一步升级优化剪切具有较高的参考价值与指导意义.     

Numerical solution, simulation and testing of the thermal dynamic characteristics of ball-screws

This research focuses on the characteristics of how a ball-screw changes its temperature corresponding to the periodic change of the end-most heat source. Based on the theory of heat transfer, this paper supplies a numerical solution to the non-homogeneous equation of heat transfer through the group explicit (GE) finite difference approach. The temperature distribution for the ball-screw at different times and directions is shown. By simulating and modeling the temperature field and thermal deformation of the ball-screw under periodically varying heat sources, this paper describes the thermal dynamic characteristics of the ball-screw under such conditions. By testing the thermal dynamic characteristics of the ball-screw, the numerical solution is validated.     

利用数字万用表检测间歇性故障

本文论述了利用福禄克的数字万用表来的记录最小/最大/平均值的功能来解决诊断间歇性电气故障的具体解决方案,并给出了详细的方法.     

甘肃省岷县马坞金矿地质特征及成矿模型

马坞金矿分布于岷—礼金成矿带的东部,距中川岩体5 km左右。通过野外地质勘查和地球化学测量,获取丰富的矿床地质特征数据,系统分析了马坞金矿矿区的矿床地质特征、矿体地质特征。围岩蚀变以中—低温热液蚀变为主,蚀变强度与金矿化强度呈正相关;极化体与已知矿化蚀变带有较好的对应关系;矿区共圈定6条矿脉,沿走向及倾向具有尖灭再现、局部膨大缩小的特点,总体呈脉状、似板状、局部为大的透镜体状等,沿裂隙发育的矿脉金品位较高。矿石结构主要有自形—半自形—它形粒状结构、包含结构、交代结构、碎裂结构、压碎结构、揉皱结构及交代残余结构等;矿石构造主要有浸染状、条带状、斑点状、（网）脉状、角砾状、蜂窝状等构造。从地层、构造、岩浆岩等三个方面分析了控矿因素。建立了马坞金矿的＂地层—构造—岩浆岩＂成矿模式。在此基础上,提出了从矿区、矿区东部、南部及外围等四个方面的找矿方向,并分析了其找矿潜力。     

保护再利用视角下南京民国建筑性能调研与提升方法研究

南京民国建筑由于其兼具卓越的历史文化价值和现实的再利用性而成为南京城市发展中不可多得的建筑资源。本文基于典型案例的调研发现有些民国建筑的建筑性能已经很差,无法为居民提供起码的使用舒适度,而且其物理性能已无法通过简单的修缮和出新来提高,必须进行建筑性能的提升设计。进而,本为对于民国建筑性能提升设计的具体方法进行研究,从建筑设计层面的改善和技术设计层面的提高两个方面详细探讨的相应的设计方法,并通过量化分析对于相应设计方法的效能进行检验和研究。     

基于GE300变频恒压供水控制系统改造设计

某生活小区原供水系统依靠阀门实现水量控制,水泵在额定状态下运行,机械磨损较大,使用成本高。通过采用GE300和变频器组合的控制系统改造,完成系统的软硬件设计及参数设置,能自动控制水泵投入的台数和电机转速,达到恒压供水目的。运行结果表明,该系统具有压力恒定,机械损耗小,节能效果显著等优点。     

GE气化炉煤气化反应的简化计算

依据GE水煤浆气化技术特点,建立了GE气化炉煤气化反应的简化计算模型,按所建立的模型进行了气化反应物料平衡和热量平衡的计算,从系统反应进程和最终煤气组分两方面验证了该模型的可靠性。通过本文建立的模型,可以获得GE气化炉在不同运行条件下煤气化炉出口煤气成分等信息,以为系统进行性能分析、工程设计提供参考。