Prototyping SOS Meta-theory in Maude

We present a prototype implementation of SOS meta-theory in the Maude term rewriting language. The prototype defines the basic concepts of SOS meta-theory (e.g., transition formulae, deduction rules and transition system specifications) in Maude. Besides the basic definitions, we implement methods for checking the premises of some SOS meta-theorems (e.g., GSOS congruence meta-theorem) in this framework. Furthermore, we define a generic strategy for animating programs and models for semantic specifications in our meta-language. The general goal of this line of research is to develop a general-purpose tool that assists language designers by checking useful properties about the language under definition and by providing a rapid prototyping environment for scrutinizing the actual behavior of programs according to the defined semantics.     

快速原形(RP)技术

快速原形技术是一种先进的制造技术,由于其高度柔性和快速性,得到了广泛的研究和应用。本文介绍了快速原形技术的产生背景,原理,典型工艺及应用范围。     

Early evaluation of future consumer AV content analysis applications with PC networks

The paper deals with software productivity improvement for consumer multimedia devices by means of PC and component technology and shows how this is done for complex real-time content analysis applications used in advanced new storage products of the future. Content analysis is a relatively new and immature technology. It is used for browsing and searching particular content items among thousands of others on “big” embedded storage devices like hard disks. As the storage capacity of hard disk and flash continues to grow rapidly, content analysis is bound to become a key enabling technology in future storage products. A major problem with content analysis features (and many other features as well) is that underlying algorithms are unstable, sometimes unavailable, or at least, very much in their infancy, and as such, subject to frequent changes. The paper describes an approach to facilitate early evaluation and integration of such immature features. This is done by packing each feature, as-is, into components and by providing PC network technology to interconnect them. In our prototyping framework, each component is an independent executable program that runs on some PC in the network, streaming AV data via TCP/IP and being controlled through UPnP networking. Experiences with large-scale prototyping activities we have carried out for the assessment of future content analysis systems, show that a PC based prototyping approach enables the integration of many different media processing features in a short time and that it allows for accurate analysis of the resource (CPU/memory) requirements of such components.

Optimum part orientation in Rapid Prototyping using genetic algorithm

Part orientation is an important parameter in the planning of a Rapid Prototyping (RP) process as it directly governs productivity, part quality and cost of manufacturing. This paper reports the design and implementation of a system for obtaining optimum orientation of a part for RP. Developed in a modular fashion, the system comprises of functional modules for CAD model preprocessing, shelling (hollowing), part orientation and optimization. CAD part model in STL format is an input to the system. The oriented CAD model is sliced and hollowed with desired shell thickness. Genetic algorithm based strategy is used to obtain optimum orientation of the parts for RP process. The objective criteria for optimization is considered to be a weighted average of the performance measures such as build time, part quality and the material used in the hollowed model. The developed system has been tested with several case studies considering SLS process.     

STL数据检验和修复

STL数据文件是快速成型最常用的数据交换文件,STL数据的错误将影响快速成型预处理的进行.本文提出一种STL数据检验和修复算法,它通过对STL数据建立拓扑关系,依据棱与面的关联度快速捕获STL数据的错误.针对不同的STL数据错误采用相应的算法,对STL数据进行有效的修复.     

快速原型制造技术在模具制造中的应用

基于快速原型制造技术(RPM)的快速模具(RT)制造技术是一种全新技术，其前端是快速设计测量技术，核心是快速原型制造技术，后端是快速制造模具技术。快速模具制造技术呈多元化的发展趋势。     

Asymmetric Single Point Incremental Forming of Sheet Metal

The use of computers in manufacturing has enabled the development of several new sheet metal forming processes, which are based upon older technologies. This paper describes modifications that have been made to traditional forming methods such as conventional spinning and shear forming, forming processes in which deformation is localized. Recent advances have enabled this localized deformation to be accurately controlled and studied. Current developments have been focused on forming asymmetric parts using CNC technology, without the need for costly dies. Asymmetric Incremental Sheet Forming has the potential to revolutionize sheet metal forming, making it accessible to all levels of manufacturing. This paper describes the genesis and current state-of-the-art of Asymmetric Incremental Sheet Forming.     

一种基于虚拟样机的弹性机构固有频率分析的新方法

对弹性机构固有频率的计算提出了一种基于虚拟样机的新方法。使用该方法可以方便迅速的计算任意空间弹性机构在整个周期中的各阶固有频率。     

虚拟样机技术在矿用带式输送机上的应用研究

将虚拟样机技术应用于矿用带式输送机的设计制造上可有效提高整机设计品质、缩短开发周期和降低开发成本。基于虚拟样机技术在机械产品研发中的技术优势与应用现状,列举了国外较为成熟的几款带式输送机专业化虚拟仿真软件,概述了国内学者借助第三方软件搭建带式输送机虚拟样机的方法策略,针对矿用带式输送机的刚-柔体结构特征,提出了建立矿用带式输送机虚拟样机多领域联合仿真的方法与设计框架,讨论了当前矿用带式输送机虚拟样机中关于输送带黏弹性体的准确建模、均匀与非均匀物料加载、柔性体输送带与刚性体零部件之间接触定义尚未妥善解决的三个关键技术问题,并给出相关解决建议与意见。     

汽车非金属件快速试制工艺

详细阐述了玻璃钢模具的产品成型工艺,该工艺是一种手工快速成型工艺,能将大型、复杂汽车非金属件的成型简单化,生产工艺简单、成型产品适用范围广泛,在汽车非金属件的快速试制上优势尤为突出。介绍了玻璃钢模具的产品吸塑成型、冷压成型、热压复合成型、发泡复合成型工艺及其应用于产品开发。