基于弹性理念的物流园空间规划布局方法探讨

物流园的发展是一个动态过程,需具备一定弹性以适应市场的发展。柳州市河西物流园空间规划在空间布局上采用空间生成模型,在地块控制上采用弹性划分方式。同时,使用按需设计的单元设计思路,形成了"一心、两轴、两带、四片、多组团"的空间结构,通过规划各层面的策略对空间规划的实施进行督促和引导,促进规划弹性的实现。     

可重组柔性装配系统发展现状与系统实例

本文介绍了近年来自动装配系统在物流优化、可重组性方面的一些重要进展。以在生产中取得良好效果的日本索尼公司 Ｓ Ｍ Ａ Ｒ Ｔ 柔性装配系统为对象,介绍了具有通用性的零件整列供料装置 Ａ Ｐ Ｏ Ｓ和自动托盘供给装置 Ａ Ｔ Ｃ及机器人装配单元 Ｓ Ｍ Ａ Ｒ Ｔ Ｃ Ｅ Ｌ Ｌ。这些装置和装配单元相结合,提高了装配系统的可重组性。     

环艺专业基础教学中创造性思维培养的缺失

通过"创造性思维的测试"证明环境艺术设计的基础教学体系所采用的契斯恰可夫教学体系存在创造性思维训练的缺失,从而影响了艺术设计专业教学质量,对其进行创新性的改造能够使契斯哈可夫教学体系更好的为设计教学服务。     

数控系统与数控机床技术发展趋势

随着计算机技术的高速发展,传统的制造业开始了根本性变革,各工业发达国家投入巨资,对现代制造技术进行研究开发,提出了全新的制造模式。在现代制造系统中,数控技术是关键技术,它集微电子、计算机、信息处理、自动检测、自动控制等高新技术于一体,具有高精度、高效率、柔性自动化等特点,对制造业实现柔性自动化、集成化、智能化起着举足轻重的作用。本文对国内外数控系统的发展概况,趋势功能及发展方向等诸多方面进行了阐述。     

基于有限元法的单边混合柔性铰链的性能分析

提出一种新型的单轴柔性铰链结构型式-单边混合柔陛铰链,由半个直圆柔性铰链和半个导角柔性铰链构成.通过有限元方法,分析了一组不同导角半径的单边混合铰链设计实例,结果表明单边该混合柔性铰链相对于一般混和柔性铰链与单边柔性铰链具有更高的柔度.并得到其柔度应力比,可用于定量地比较各种柔性铰链的性能差异.提出的单边混合柔性铰链为面向结构紧凑、大位移、高精度的工程应用提供了有价值的参考.     

Analytical studies for buckling and vibration of weld-bonded beam shells of rectangular cross-section

An approach to analytical solution is presented for vibration and buckling of thin-walled tubular beam shells typical of automotive structures, which are fabricated by joining sheet metal stampings along the two longitudinal edges with periodic spot welds, adhesive bonding, or combination of spot welds and bonding, known as weld bonding. Solutions are obtained for such beam shells of rectangular cross-section with two opposite ends simply supported. The beam shell is modeled as an assembly of the constituent walls and Levy-type formulation is used to obtain a series solution for the transverse displacement of each of the walls. The challenge of expressing the discrete point support conditions at the spot welds by a continuous function is addressed using the flexibility function approach used in literature. The flexibility function, used earlier to represent the flexibility distribution along weld-bonded edges of rectangular plates with periodic spot welds, is used here. The characteristic equations are obtained by satisfying the displacement, slope, shear, and moment equilibrium at the mating edges of the walls including the two weld-bonded edges and the compatibility conditions at the spot-weld locations. This approach to analytical solution, described here for thin-walled beam shells of rectangular cross-section, can be suitably adopted for more general cross-sections and joints along non-symmetric edges. A parametric study is undertaken to show the effect of aspect ratio of the beam shell, adhesive joint parameters, and the number of spot welds on the elastic buckling loads and the natural frequencies. Such parametric studies can be of use to designers in arriving at an optimal joint configuration of weld-bonded beam shells from buckling and vibration considerations.     

Adhesion improvement of hydrogenated diamond-like carbon thin films by pre-deposition plasma treatment of rubber substrate

For reduction of friction and enhancement of wear resistance of dynamic rubber seals, thin films of hydrogenated diamond-like carbon (DLC) have been deposited on hydrogenated nitrile butadiene rubber (HNBR) via magnetron-enhanced plasma chemical vapor deposition (ME-PCVD). Pre-deposition plasma treatment of HNBR substrate is proved to be crucial for the improvement of film performance due to enhanced interfacial adhesion. The columnar structure and the crack network formed during deposition enhance the flexibility of DLC thin films and exhibit strain tolerance up to 5%. Below 50% stretch strain and after unloading, thin DLC films of ∼ 300 nm thickness still adhere on the rubber substrates and no spallation or delamination is observed. The thin DLC film deposited on Ar-plasma pre-treated rubber at − 400 V substrate bias potential exhibits a very low coefficient of friction of 0.175 (compared to > 1 of uncoated HNBR rubber). After tribotests even under high normal load of 3 N, almost no wear can be seen on the films. Such tribological property is even better than that of 1 µm thick DLC or Me-DLC coated rubbers.     

Flexible Operation of Coal Fired Power Plants with Postcombustion Capture of Carbon Dioxide

Carbon capture and storage is one family of technologies that could be used to significantly reduce global carbon dioxide (CO2) emissions. This paper reviews the likely flexibility of power plants with postcombustion capture, with a focus on an improved characterization of the dynamic performance of power plants with CO2 capture. The literature has focused on design and optimization for steady state operation of power plants with capture, often at a single design point. When dynamic behavior is considered, it is possible that designs should be altered for best overall plant performance. Economic trade-offs between improving transport and storage scheme flexibility and constraining power plant operations should also be carefully analyzed, particularly if the captured CO2 is to be used in another process such as enhanced oil recovery. Another important aspect of real plant operation will be adhering to legislative requirements. Further work is required to identify mechanisms that allow flexible operation without undermining any targets set for storing CO2 and/or restricting global CO2 emissions.     

SOA中业务服务粒度与流程柔性的关系研究

SOA是以提高流程柔性为基本目标的IT架构方法,业务服务粒度在SOA项目中起着关键的作用,该文研究目的在于解释业务服务粒度与流程柔性间的基本关系。首先分析了SOA环境下业务流程的范围柔性和响应柔性两个关键维度并给出定义;基于服务元素和流程协调的研究给出了这两个维度的量化计算方法;构建了业务服务粒度的分析模型并进行量化分析。结果表明SOA环境下随着业务服务平均粒度的增大,流程的范围柔性将逐渐减小,流程的响应柔性将逐渐增大,而流程的整体柔性度将先逐渐增长,达到一定的程度后再逐渐下降。