重庆市建筑开挖边坡稳定性评价及支护措施探讨

山城重庆的建筑用地开挖过程中，通常采用了直立切坡。文章讨论了对于这种典型的岩质边坡，现行支护设计时采用库仑土压力理论计算推力的不合理性，并提出了相应的改进办法，然后通过有限元、拉格朗日差分分析等数值模拟手段对重庆市建筑开挖边坡的稳定性程度、变形破坏方式以及支护处理措施进行了研究。     

夏季不同浓度的NAA对台湾杉扦插苗的影响

本文研究了夏季不同浓度的NAA对台湾杉扦摘苗成活率的影响,结果表明,6、7月份用500ppm的NAA处理扦插苗,成活率最高。     

新型逆变切割电源的研制

研制了一种新型逆变切割电源，该电源的变压器选用具有优异高频磁性能的非晶态磁性材料，采用单片机控制电路，试验证明其具有高稳定性及高效节能的特点。     

金属切削条件的智能优化研究

本文通过建造一个符号－数值型专家系统探讨了金属切削条件的智能优化问题。运行结果表明，所建智能优化系统ＯＰＴ—ＥＳ能在一定范围内完成优化法自动选择和优化子程序的自动调用执行。     

Research on the Cutting Performance of Cubic Boron Nitride Tools

There were only two kinds of superhard tool material at the past, i.e. diamond and cubic boron nitride (CBN). Manmade diamond and CBN are manufactured by the middle of 20th century. Various manufacturing methods and manmade superhard materials were developed later. They were widely used in different industry and science areas. Recently, a new kind of superhard tool material, C 3N 4 coating film, had been developed. American physical scientists, A. M. Liu and M. L. Cohen, designed a new kind of inorganic c...     

An Investigation of Laser Assisted Machining of Al_2O_3 Particle Reinforced Aluminum Matrix Composite

The Al 2O 3 particles reinforced aluminum matrix composite (Al 2O 3p/Al) are more and more widely used for their excellent physical and chemical properties. However, their poor machinability leads to severe tool wear and bad machined surface. In this paper laser assisted machining is adopted in machining Al 2O 3p/Al composite and good result was obtained. The result of experiment shows in machining Al 2O 3p/Al composites the cutting force is reduced in 30%～50%, the tool wear is reduced in 20%～30% an...     

自激振动时切削力与切削深度及切削面积的相关分析

本文利用动态数据系统（ＤＤＳ）法对动态切削过程的多重再生效应作了较深入 介绍，进而对切削力与切削深度、切削力与切削面积之间的互相关性进行定量与定 性分析，在此基础上探讨了动态切削刚度的基本概念并给出了切削刚度新的定义。     

Fibre laser cutting of thin section mild steel: An explanation of the ‘striation free’ effect

This paper presents the results of an experimental and theoretical investigation into the phenomenon of ‘striation free cutting’, which is a feature of fibre laser/oxygen cutting of thin section mild steel. The paper concludes that the creation of very low roughness edges is related to an optimisation of the cut front geometry when the cut front is inclined at angles close to the Brewster angle for the laser-material combination.     

基于相关机会目标规划的钢板切割分配建模

为实现从多个不确定供给端向数控切割机分配钢板的多目标要求,运用相关机会目标规划对钢板切割的供给-分配系统进行建模.该模型修正了同一优先级下对多目标的处理过程,并在给定优先级下极小化各目标偏差,采用融合随机模拟、神经网络和遗传算法的混合智能算法进行求解.计算结果极大化了关键设备完成最大切割长度的机会,提出了加大临时抽板量的同时保证分配有序性的方法,基本满足了生产的多目标要求.结果表明,将相关机会目标规划用于多供给端分配系统中,可以消除和控制由于供给的不确定性对生产造成的影响.     

TBM多刀不同切削顺序破岩过程的数值研究

为了研究不同切削次序对TBM刀具破岩过程的影响,基于2D离散单元法,利用离散元仿真软件建立了无围压条件下三把TBM刀具按不同次序截割节理不发育岩石的仿真模型．在此基础上设计了一组数值试验,成功地模拟出了TBM刀具在切割岩石时,岩石裂纹生成、扩展和岩石破碎块形成的全过程．仿真结果表明：不同时加栽时所需的刀具临界应力更大;...