Computer-aided manual work station as an extension of the product-independent flexible factory automation concept

This paper discusses the extension of a concept for product- and process-independent factory automation to include functions for the control and coordination of computer-aided manual work stations. Subsystems already implemented and standardised for factory-wide integration in all production processes have been taken into account. They represent components of the computer-integrated manufacturing factory of the future.     

An extension of the Hertz theory for three-dimensional coated bodies

This paper presents a work on extending the Hertz theory for circular and elliptical point contact problems involving coated bodies. The extended form of the Hertzian formulae are adopted to express maximum contact pressure, contact radius, and contact approach in terms of applied load, equivalent radius, and an extended equivalent modulus that properly considers the presence of a coating. The extended equivalent modulus is a function of Youngs moduli and Poissons ratios of the coating and the substrate, coating thickness, and a parameter, which is obtained through substantial numerical simulation. The extended Hertzian formulae are easy to use and give accurate predictions of contact characteristics.     

An extension of the Hertz theory for 2D coated components

The classic Hertz theory is not applicable when components in contact have coatings. An extension of the Hertz theory is presented in this paper for contact between coated cylinders. The concise form of the Hertz theory is adopted to express the maximum contact pressure and contact half-width in terms of applied load, equivalent radius, and an extended equivalent modulus. According to the form of an analytically known frequency response function, the extended equivalent modulus due to the presence of the coating is a function of Youngs moduli and Poissons ratios of the coating and the substrate, the coating thickness, and a parameter, which is obtained through substantial numerical simulation. This extension is easy to use and yields accurate predictions of the maximum contact pressure and contact half-width.     

An extension of the static shakedown theorem to inelastic cracked structures

Here we have investigated under which conditions elastic-perfectly plastic, cracked bodies subjected to variable loads shake down. For this purpose, an extension of the static shakedown theorem (Melan’s theorem) is presented by using a crack analysis developed by Nguyen Quoc Son in the framework of the concept of generalized standard materials.     

An object-oriented simulation and extension for tandem AGV systems

An object-oriented simulation modelling environment, AgvTalk, is presented to provide flexible modelling capabilities for the simulation of many alternative automated guided vehicle (AGV) systems. The hierarchical features and modularity of AgvTalk create possibilities for the extension and reuse of simulation object components. The detailed behaviour of each object in the AGV system can also be modelled easily and exactly in AgvTalk because there are no limiting modelling constructs. The modelling capabilities of AgvTalk are demonstrated by designing and simulating a conceptually different configuration AGV system, known as the tandem configuration. For the tandem and conventional AGV systems, the characteristics and design methodology in AgvTalk are described. Simulations between the two systems are compared using AgvTalk in a job shop environment.     

基于集散控制技术的电梯群控系统方案

随着信息技术和控制技术的不断发展,基于集散控制技术的电梯群控系统的开发也成为楼宇自动化控制技术研究的热点.在本文中研究了基于IPC构成的上位机与PLC构成的下位机组成的电梯集散控制系统的组成和特点,构建了系统的通信模式,并介绍了上位机和下位机系统的主要硬件的选择原则.     

基于联合成功率的飞机总体设计评价方法研究

为了提高设计决策的科学性和稳健性,对不确定因素影响下的飞机总体方案评价问题进行了研究,提出了一个以联合成功率为综合评价指标的决策方法.根据多变量概率理论,定义了联合成功率的数学表达式,研究了联合概率密度函数的计算方法:联合概率模型;依托联合概率分布,将概率设计方法和多准则决策方法进行有机结合,给出了基于联合成功率的飞机总体方案评价步骤.最后,通过算例分析,对该方法的实际应用进行了演示,并验证了联合概率模型的合理性.     

An extended interpretation of THD concept in the wake of ship electric power systems research

The paper is to investigate seemingly a simple problem of THD interpretation in the wake of standards’ definitions and measurement methods. The consequences of application of various definitions of the considered factor are profoundly discussed on the basis of the real voltage waveforms registered in two different ship systems. Particularly, the results of determining of THD by means of various definitions are presented. Finally, the proposed amendment of related rules is provided. The aim is to overcome hitherto existing ambiguities.     

反馈概念的再认识

通过对几种典型控制的分析,说明反馈在控制领域的应用不仅是反馈控制,它更重要的作用是其监控性,将开环控制的主动性、闭环控制的监控性、反向控制的强制性、变结构控制的“完全自适应性”以及反馈控制的系统内部稳定性等在反馈的监控作用下综合集成起来构成了新型的反馈控制,使大家对反馈概念有个新的认识和扩展。如何充分利用反馈中的信息是深入研究控制问题的一个重要方面。     

An insight concept to select appropriate IMFs for envelope analysis of bearing fault diagnosis

Traditional envelope analysis must examine all the resonant frequency bands during the process of bearing fault detection. To eliminate the above deficiency, this paper presents an insight concept based on the empirical mode decomposition to choose an appropriate resonant frequency band for characterizing feature frequencies of bearing faults by using the envelope analysis subsequently. By the band-pass filtering nature of the empirical mode decomposition, the resonant frequency bands are allocated in a specific intrinsic mode function. The inner or outer ring of bearings scratched intentionally is used to validate the feasibility of the proposed idea, and comparisons with the traditional envelope analysis are addressed. The experimental results show that the proposed insight concept can efficiently and correctly diagnose the bearing fault types.     

An improved method for predicting discharge of homogeneous compound channels based on energy concept

Accurate estimation of flow discharge in a compound river channel is increasingly important in river management and hydro-environment design. In this paper, a new model is developed to improve the prediction of flow based on Energy Concept Method (ECM) and Weighted Divided Channel Method (WDCM) along with the apparent shear stress at the interface between main channel and floodplain. The new model is compared with a wide range of our experimental data and the data available in the literature. The 27 datasets used include homogenous symmetric channels (22 datasets) and asymmetric channels (5 datasets) with various aspect ratios [channel total width (B) at bankfull / main channel bottom (b) =1.5–15.8], and bed slopes (S_o = 4.3 × 10⁻⁴–1.3 × 10⁻²). It was found that the new model has significantly improved the accuracy of flow prediction compared with the traditional Divided Channel Method (DCM), and has also considerably better results than the ECM and WDCM methods against all the datasets, particularly for relatively low flow depths of floodplain where the flow discharges are most difficult to predict correctly. The new model predicts the total discharge well for both symmetric and asymmetric channels, within an averaged relative error of about 5%.     

A generalization of the concept of size

The size of a set is defined without ambiguity as a ratio of homothety with an elementary set having the same shape. In order to generalize this, we compare the object studied with the elements of the family {λB} of the homothetics of B. The size λ of a particular element B is going to act as a measure of the object. If the latter is made up of individualized elements, we can calculate the size of each one and construct the size histogram, assuming for example that the size of a connex component C according to B is the size of the largest B included in C. (Examples: inscribed circle radius, maximum intercept.) For any object (alveolar lung space, pore system), the size at each point x is defined as the largest λB included in the object and containing x. The set of points x of a given size λ is related to the opening with respect to λB. This geometrical transformation of opening has mathematical properties similar to those of the sieving process, and is the basis of the size distribution concept as generalized by mathematical morphology. In the plane, the texture analyser allows the above measurements.     

Improving the concept of an asynchronous cyclotron

The main results from improving the concept of an asynchronous cyclotron, the latest version of which has been dubbed a variable-phase asynchronous cyclotron, are presented. Its characteristics are considered using the example of a six-cavity scheme. Its advantages are shown for the multistage acceleration of ultra-high-power proton beams with energies of 2–1000 MeV and continuous currents of up to hundreds of milliamperes over ordinary isochronous and superconducting versions of cyclotrons with separated orbits. The problems of the beam halo are also discussed, and easier possibilities of obtaining spherical bunches for reducing the particle losses are shown. The cost of creating such an accelerator is estimated, and the main relationships for the preliminary selection of its calculation parameters are presented.Translated from Pribory i Tekhnika Eksperimenta, No. 1, 2005, pp. 14–23.Original Russian Text Copyright ¢ 2004 by Tumanyan, Sargsyan, Nikogosyan.     

通用扩展技术在软件设计中的应用

在应用软件设计中,为了满足不同客户的需求,通过设计通用扩展接口来增加软件的通用性,该扩展接口,利用脚本和专用接口函数来适用用户复杂需求,是一种有效的应用扩展方法.     

电主轴的创新概念

在生产型机床上，电主轴被视为技术水平的体现。通过近年来的不断改进，电主轴已经发展成为一种技术成熟的产品，能满足各种不同的要求。然而，电主轴当前的工艺水平怎样?今后如何发展?这些都引人关注。     

高性能理念——大正前角可分度刀片的多角度铣刀

近年来,现代铣削加工中心一直在不断精化,特别是在机床轻量化、提高动态性能和通用性等方面,例如一次装夹完成五面加工。在加工过程中,当首推高性能控制系统,它成就了高速成五轴联动加工。与此同时,宽调速范围的通用主轴几乎可以涵盖所有材料的加工。     

An extension of laser-interferometric CT measurement to unsteady shock waves and 3D flow around a columnar object

The 3D laser-interferometric CT measurement of the unsteady flow field induced by shock wave discharging from a circular nozzle next to a short columnar object in a shock tube experiment is presented as an extension of previous work of 3D measurement of open flow field. The 3D density distribution around the object is reconstructed with FBP (filtered back projection) and MLEM (maximum likelihood expectation maximization) algorithm from the incomplete projection data caused by the obstruction of the observation light for interferometry with an object in a test section. The 3D density-gradient distributions are also evaluated from the resultant 3D density distribution, we demonstrate that laser-interferometric CT measurement of interaction field of shock waves and an object come to sight.     

Wear modeling and the third body concept

Many laws already exist for wear, but few are really predictive. In order to better understand the wear process, classical wear models are compared to the third body concept. This concept emphasizes that particle detachment mechanisms, the flow of these particles inside the contact, and their ejection from the contact have to be considered in order to describe wear effectively. An analytical demonstration is proposed, that considers the particle detachment process and the particle ejection process separately. These two processes are then linked by a mass equilibrium equation. In continuous sliding, a steady-state wear process can be identified in which the mass of third body particles in the contact remains constant. The source flow and the wear flow (representing, respectively, particle detachment and particle ejection) become equal and constant in time. Initially presented via numerical investigations, this analytical model is then confirmed by simple experiments.