面向模具企业的物料管理系统的研究

在分析我国模具企业物料管理特点的基础上,结合自主开发的模具企业管理系统———e Man在多家模具企业成功应用的经验,介绍了系统中物料管理模块在模具企业中的设计、采购、制造和库存等方面的应用与功能,并引入消息机制对采购环节的变更进行及时的跟踪与反馈处理,从而实现了企业信息资源的共享和原材料的及时准确供应,达到了降低企业物料采购成本及管理成本的目的。     

The effect of drying treatment on the fodder quality and tannin content of two provenances of Calliandra calothyrsus Meissner

The effects of freeze drying and of air drying at 30 °C on the nutritive value of Calliandra calothyrsus leaves were evaluated, using material from two provenances grown together under controlled greenhouse conditions. Freshly harvested leaf of each provenance was compared with the dried treatments in terms of in vitro digestibility, content of extractable, protein‐bound and fibre‐bound proanthocyanidin (condensed tannin) and protein precipitation activity of the extractable fraction, as well as crude protein and fibre content. The effect of long‐term (12 months) storage of fresh‐frozen and dried leaf was also evaluated. Provenance was found to have a major effect on most of the traits, and large differences between the provenances in proanthocyanidin structure were found by high‐performance liquid chromatography, with the tannins of one provenance consisting mainly of catechin/epicatechin subunits (producing cyanidin on treatment with butanol/HCl), and those of the other mainly gallocatechin/epigallocatechin subunits (producing delphinidin with butanol/HCl). This also resulted in large differences in colour yield in the butanol/HCl assay for proanthocyanidins, necessitating separate standards for each provenance. Both drying treatments tended to increase digestibility, though the effect was only significant for one provenance. Air drying, but not freeze drying, increased proanthocyanidin binding to protein, but not to fibre, in both provenances. Long‐term freezing reduced proanthocyanidin content by about half and should be avoided in tannin research. The study suggests that careful air drying, without excessive heating, may not reduce the nutritive value of C calothyrsus, though this needs validation through feeding studies with ruminants. © 2000 Society of Chemical Industry     

基于知识重用的标准件建库方法研究

知识重用是一种在已有的设计知识和经验的基础上,进行新产品设计的过程。通过分析基于知识的标准件模型知识表达、重用、搜索等关键技术,提出了将标准件的尺寸信息、开孔信息、装配信息、配置信息等提取出来,建立基于知识重用的标准件库,从而实现标准件的自适应,提高了产品设计的质量和效率。     

基于KBE的汽车覆盖件冲压工艺方案设计

汽车覆盖件的冲压工艺方案设计是一个复杂且经验性强的创造性过程,需要一种支持多种知识表达模式和多智能决策技术的方法,解决工艺方案决策问题.通过以工艺特征为核心来表达知识,建立了基于KBE的覆盖件工艺知识模型,采用基于知识驱动决策树表达模式的特征转换机制来实现设计特征到工艺特征的映射,在工艺知识库的支持下完成工艺方案设计.实现了知识的多种描述形式及其应用,有效地解决了工艺方案设计中基于图形、规则及经验知识的决策判断,提高了汽车覆盖件工艺方案设计的智能化程度.     

Ultrasonic beam propagation through a bimetallic weld—A comparison of predictions of the Gauss-Hermite beam model and finite element method

In this paper, predictions of two models for the propagation of ultrasonic beams through a two-dimensional, bimetallic weld geometry are compared. The finite element method can predict beam propagation through quite general geometry with high accuracy. This model, however, requires significant computational time. On the other hand, the approximate Gauss-Hermite model offers considerably greater computational speed, but has lower accuracy in certain regions and cannot treat the most general geometries and inhomogeneities in material properties. This paper compares the performances of the two models for the case of the two-dimensional, bimetallic weld consisting of multiple layers, some of which have anisotropic properties. It is found that the results of the two models are in good agreement in the vicinity of the central ray, and that the deviation increases as one moves away from the axis. Also, as the beam propagates through multiple interfaces, the accuracy of the Gauss-Hermite solution decreases.     

注塑成形CAE系统分析模型研究

目前共有4种分析模型应用于注塑成形CAE系统:1维分析模型;2·5维中面分析模型;2·5维双面网格分析模型;3维实体分析模型。详细讨论了2·5维中面分析模型,2·5维双面网格分析模型和3维实体分析模型3种分析模型的优缺点,并通过理论分析和实例模拟结果的比较,研究了不同分析模型对注塑分析结果的影响,提出了在使用CAE系统中选择分析模型的规则。     

基于UG的复杂板料件多工步展开模拟

简要介绍了有限元逆算法,论述了复杂板料件数值成形模拟技术中多工步展开的几个关键技术问题。并在UG平台下,应用有限元逆算法的求解器FASTAMP,对系统模块进行架构,实现了复杂板料件多工步展开的模拟。该模拟结果为某些模具CAD/CAE软件提供复杂板料件成形的中间工步,使之完成后续工艺模拟处理。     

Zr基块体非晶合金在过冷液态区微正挤压实验研究

为了研究Zr55Cu30Al10Ni5大块非晶合金在过冷液态区内的微正挤压变形行为,采用不同尺寸非晶合金圆柱形棒料在不同长度凹模工作带下进行了微正挤压实验。实验结果表明：所选非晶合金在成形温度450℃、初始应变速率0.001～0.01s-1的条件下正挤压是可行的;随着坯料尺寸减小,其单位挤压力和挤出胀大比均增大,且挤压成形力表现出不同的变化趋势;坯料在短凹模中的单位挤压力和挤出胀大比分别大于在长凹模中的单位挤压力和挤出胀大比。     

Profile Extrusion: Experimental Assessment of a Numerical Code to Model the Temperature Evolution in the Cooling/Calibration Stage

Designing an industrial calibration system that ensures fast and uniform cooling of a complex extruded profile is always a difficult task. Numerical tools are a valuable aid for the design of these systems in order to achieve fast, low‐cost, and effective solutions. This work comprises the experimental validation of a numerical code, previously developed to support the design of profile extrusion calibration systems, using data collected from an industrial extrusion line. The referred numerical code was developed in the open‐source computational library, OpenFOAM, being able to predict the heat exchanges between the polymer and the calibrator during the profile extrusion cooling stage. The good agreement obtained between the numerical code predictions and the experimental measurements allowed us to confirm the code accuracy. Subsequently, and in order to demonstrate the usefulness of the numerical code, a numerical study was carried out based on an optimization algorithm aimed at improving the performance of the studied calibration system. As a result, the study led to the proposal of an alternative setup, which presents a simpler constructive solution and a better performance than the existing one. POLYM. ENG. SCI., 59:2367–2376, 2019. © 2019 Society of Plastics Engineers     

Preparation of Oriented Barium Titanate Thin Films by Combination of Electrophoretic Deposition with Hydrothermal Treatment

Highly oriented barium titanate (BaTiO 3) thin films on Pt substrate were fabricated by combination of electrophoretic deposition with hydrothermal treatment.The structure and morphology of thin films were characterized by X-ray diffraction and field-emission scanning electron microscopy.It is found that the titania precursor film,Ba(OH)2 concentration and hydrothermal temperature play crucial roles in the film morphology and orientation.The BaTiO3 thin films with highly (110) preferred orientation can be f...