NURBS曲线在航标灯设计中的应用

文章介绍了航标灯的基本光学系统,经过理论推导,给出了航标灯透镜设计的基本计算公式,并与计算机辅助设计技术相结合,利用NURBS曲线拟合出航标灯透镜的齿形,实现了设计的自动化.     

Light Mediations: Introduction

Abstract

This introduction argues that the study of light and lighting devices, and the light mediations yielded by them, is important for scholars of material religion. Discussing the four articles on aesthetics of light in Christianity, we argue that synthesizing metaphorical and physical uses of light allows for a deep understanding of the processes through which a professedly immaterial transcendent becomes real for religious practitioners in the material world. Inspired by these contributions and the two essays in the In Conversation section, we plead for a methodology of following the light in scholarly research.     

Centralized solar lantern charging station under ‘lighting a billion lives’ campaign: a technological evolution

To mitigate the use of kerosene for rural lighting and to promote utilization of solar energy, solar lanterns prove to be a viable and promising option. For addressing the issue of large‐scale dissemination of solar lanterns, a rental model is implemented though ‘Lighting a Billion Lives (LaBL)’ campaign. This paper deals with the technological development and customization of the Centralized Solar Lantern Charging Station (CSLCS) under this campaign. A single unit in a typical LaBL charging station consists of a Solar Photovoltaic (SPV) module feeding a junction box (JB) containing multiple ports for charging of a certain number of lanterns simultaneously. The first version was developed with an available Compact Fluorescent Lamp (CFL) lantern model. The design calculation of the various components considering the various climatic conditions in India and other required parameters are presented. Further, the optimization of the modular design of the charging station based on the above analysis is given. Subsequently, the second version was developed with features addressing the challenges faced in the first version. The field demands and feasibility of incorporating modifications addressing them are reported in detail. Further, a more advanced and customized third version lanterns with additional features was developed. The versions also involved considerable modifications of the JB and lantern circuitry. Comparative analysis of the obtained efficiencies of all the three configurations is presented. The concluding section proposes methods that lead to the way forward in establishing a more rugged and customized system addressing the issues of seasonal and technological constrains more efficiently. Copyright © 2010 John Wiley & Sons, Ltd.     

新保利大厦特式吊楼结构的抗震分析与设计

北京新保利大厦特式吊楼是一个悬挑长度为25m的巨型悬挂结构,吊楼的根部固定在大厦的一个混凝土核心筒上,端部由4根主钢索向上拉住,4根主钢索的上端分别固定在大厦的3个混凝土核心筒上,形成了特式吊楼的既悬挑又悬挂的结构体系。该种结构体系在国内外首次使用。对新保利大厦特式吊楼进行了基于性能的抗震设计,并进行了计算分析,全面论述了特式吊楼的结构特点、设计方法及其受力特性。