纸箱结构参数化设计中的数据处理

介绍了利用AutoCAD二次开发平台对瓦楞纸箱结构图进行参数化设计的过程,解决一些参数化设计中的数据处理的问题,包括表格的数值化和程序化的过程。在数值化时,首先将各种查询表格转成Microsoft Access关系数据库;程序化是将具有一定逻辑关系的数据以程序的方式进行存储。以上数据通过VBA建立的窗体,结合客户输入的已知产品的信息,检索出相应的数据,自动计算出纸箱结构最优化尺寸等参数,并绘出纸箱的展开图。     

参数化图形管理系统

目的讨论参数化图形管理系统ＰＤＭＳ（ＰａｒａｍｅｔｒｉｃＤｒａｗｉｎｇＭａｎａｇｅｍｅｎｔＳｙｓｔｅｍ）的原理和关键技术．方法本系统采用交互式绘制草图方式定义零件原型图,对原型图进行参数化处理,从参数图中可以生成不同尺寸参数值的零件图．结果本系统不仅可以建立参数化标准件库,而且可用于建立复杂结构的参数化非标准件库．结论本系统运行良好,具有很强的实用性     

LOM系统X—Y执行机构设计

Ｌ Ｏ Ｍ 系统中,利用并行口连接计算机和成型机,通过适当扩展并行口,实现计算机对 Ｘ Ｙ 执行机构的精密、安全控制。     

建筑空调能耗关键变量通用提取方法及工具的开发

建筑空调能耗关键变量是所有可能对建筑空调能耗产生影响的变量中起决定性作用的少数变量.关键变量的确定对于常用的两类能耗预测模型(白箱模型和黑箱模型)都非常重要,基于关键变量而非全部变量建立模型可大大简化建模过程但不过度损失模型精度.关键变量的确定是比较复杂的过程,且容易受到初始边界条件的影响.提出1种关键变量通用提取方法...     

用Pro/ENGINEER创建斜齿轮实体模型

Pro/ENGINEER功能强大,它的参数化设计理念深受用户青睐。目前它已成为我国的主流三维CAD软件。运用Pro/ENGINEER设计数字样机精确、效率高、经济性好,可避免许多不必要的浪费,并且可达到直观的、立体化的视觉效果,方便在制造过程中用户与厂家沟通,以便设计出用户更满意的产品。     

一类不确定离散系统的严格正实分析和设计

考虑了一类不确定离散多变量系统严格正实分析和控制问题,其中不确定参数具有非负性.分析了系统鲁棒稳定且严格正实的条件,讨论了状态反馈、输出反馈使闭环系统鲁棒稳定且严格正实的问题.将不确定系统的鲁棒严格正实分析和设计转化为确定系统的严格正实分析和控制,得到了系统鲁棒稳定且严格正实的充分必要条件.最后给出了鲁棒严格正实控制问题的可解条件及控制器的综合方法.     

BIM技术在装配式内装设计中的应用

阐述了装配式装修的概念、优势和BIM技术在装配式装修行业的应用现状.结合BIM软件,从族库建立、参数化建模、碰撞检查、施工图出图、工程算量等方面提出了装配式装修设计的技术路线.以全装配式装修研发实验房项目为例,详细介绍了装配式装修BIM设计过程,验证了技术思路的可行性与合理性,为推动BIM技术在装配式装修行业的应用提供...     

Kinetics of sensory quality changes in soymilk during thermal processing,by parametric and non‐parametric data analyses

Soymilk was subjected to various heat treatments at 90, 120 and 140 °C for various lengths of time. The colour and flavour of the soymilk samples were evaluated by a sensory panel consisting of eight semi‐trained assessors on (1) a 9‐unit hedonic scale, with analysis based on the assumption that the units are equidistant, and (2) a 15‐point hedonic ‘Smiley’ pictorial scale, the results being analysed non‐parametrically. The proportion (%) of ratings higher than or equal to/higher than the overall median of the samples was used as a rigorous estimate of product quality. These values were used to determine the colour and flavour changes in heated soymilk and their temperature dependence. The Z‐values derived from the parametric and non‐parametric analyses were in close agreement, ranging from 31 to 33 °C and from 30 to 32 °C for colour and flavour respectively. © 2000 Society of Chemical Industry     

Chaotic oscillator configuration using a frequency dependent negative resistor

A chaotic oscillator configuration employing a frequency‐dependent negative resistor (FDNR) as the only active element is proposed. The configuration relies on a simple two‐terminal passive device; namely a general purpose signal diode, to provide the necessary non‐linearity. The structure requires no floating elements and is independent of any circuit specific realization of the FDNR. Experimental results, PSpice simulations and numerical simulations of the derived mathematical models are included. Copyright © 2000 John Wiley & Sons, Ltd.     

On the design of approximate non‐linear parametric controllers

This paper focuses on the design of non‐linear parametric controllers, around a nominal input/output trajectory of a discrete‐time non‐linear system. The main result provided herein is a relationship between the tracking performance of the closed‐loop control system in the neighbourhood of a nominal trajectory, and some local features (the first‐order linear approximations about the nominal trajectory) of the non‐linear mappings which characterize the plant and the feedback controller. Such a result can be used to predict the dynamic behaviour of the control system, and to reduce the computational complexity of the optimization task associated with the tuning of the parametric feedback controller. Copyright © 2000 John Wiley & Sons, Ltd.