AutoCAD二次开发技术在绘制船体外板展开图上的应用

利用二次开发工具VBA及AutoLISP进行混合编程实现了:(1)肋骨型线图上的构件在外板展开图上的自动展开;(2)外板展开图上的板缝线自动返回到肋骨型线图;(3)板缝线在两张图上的自动光顺修改。本文对以上功能的实现过程及关键技术做了详细阐述。     

基于AutoCAD的外板自动展开技术

在船体结构详细设计阶段,外板展开图通常经由Auto CAD绘制而成。此类通用绘图软件对专业领域的针对性支持相对有限,在制图过程中仍需要大量的手工介入,操作繁琐且低效。通过对Auto CAD进行二次开发,利用计算机程序自动完成展开过程中的重复性工作,可提高其专业化程度,从而提高外板展开的效率。程序以肋骨型线图为输入数据源,通过对图形添加扩展数据来识别相关肋骨型线,实现外板的快速全自动展开。使用该技术,能极大地缩短外板展开过程。     

螺旋桨伸张轮廓参数化绘制程序的设计

介绍了基于AutoCAD VBA螺旋桨伸张轮廓的参数化绘制方法,包括图样绘图环境的设计、螺旋桨伸张轮廓的计算与绘制,以及程序菜单的设计和程序代码的自动加载等,列举了用VBA编写的相关程序。     

螺旋桨伸张轮廓参数化绘制程序的设计

介绍了基于AutoCAD VBA螺旋桨伸张轮廓的参数化绘制方法,包括图样绘图环境的设计、螺旋桨伸张轮廓的计算与绘制,以及程序菜单的设计和程序代码的自动加载等,列举了用VBA编写的相关程序.     

船体外板自动展开程序

在船舶结构设计中,外板展开图的信息是船舶设计建造的关键,它的精准性直接影响船舶的建造质量。利用Auto LISP语言编制的外板自动展开程序功能,阐述了按水线、纵剖线和边舱展开及自由展开几种外板展开模式的原理和实现方法,并就程序编制和使用过程中的注意事项作了技术说明。实践证明,该程序的应用提高了外板展开图的绘制精度,保证了图纸质量。     

JHT-2型数控绘图控制机

一、前言JHT-2型数控绘图机,是南京工学院和求新造船厂在毛主席“独立自主、自力更生”的方针指引下,实行厂校挂钩和教学、科研、生产三结合而共同研制的,于1972年试制成功,在1975年8月六机部召开的船厂数控设备经验交流会上进行了鉴定。本机是为适应造船工业发展的需要而研制的,它在船体型值→船体数学光顺→绘制横剖面图→结构放样(外板展开→外板下料,肋板排题→肋板下料)的工艺流程中,用以绘制剖面图,和完成外板、肋板下料的绘图工作。     

船体肋骨型线图和外板展开图的计算机设计与绘制

本文主要讲述了应用计算机外板展开程序来设计和绘制船体肋骨型线图和外板展开图的方法.     

船底外级计算机辅助设计

本文介绍利用计算机进行船底外板板缝的交互设计来提供板缝同横接缝的交点坐标以及同所有肋骨线的交点坐标的方法.输出结果可用来绘制板缝线和作为外板展开的依据.克服了最佳展开宽度处理外板方法的缺点,能满足建造工艺,而且算法简单.     

船体外板展开算法及程序实现

对船体肋骨型线图和外板展开图的计算及绘制方法进行了研究,运用参数化三维实体建模技术解决船体外板的展开问题.使用VB.NET和SolidWorks图形软件开发了船体外板展开过程的计算机程序,并将建立的外板模型信息保存到数据库中,提供网络远程数据访问服务,用于生产与设计的需要.     

基于面向对象技术的参数化CAD系统研究

通过分析参数化绘图的原理及方法,讨论了基于面向对象技术的CAD系统如何实现产品结构的参数化绘图,采用高级语言Visual Basic Application(VBA)与AutoCAD数据接口技术,实现了齿轮系列产品结构的二维、三维展开图等的参数化设计.     

预应力混凝土大直径管桩在北方港口工程中的应用实践

预应力大直径混凝土管桩自20世纪80年代研制成功后;在我国南方各大港口得到了推广应用,但在我国北方港口中还没有大批量使用的先例。东营港扩建工程在北方港口首次大批量使用,通过进行大管桩抗冻、试桩等试验,沉桩获得成功。     

Decentralized Coastal Zone Management in Malaysia and Indonesia: A Comparative Perspective 1

Transferring decision-making process from central to local government and enhancing the role of local communities in managing coastal zones is an increasing commitment by governments in Southeast Asia. This article analyzes decentralized coastal zone management in two neighboring countries, Malaysia and Indonesia. The Federal system in Malaysia is argued to be able to influence more decentralized coastal zone management and to promote community-based management approaches. Meanwhile, the large diversity of coastal resources and communities combined with a still as yet tested decentralization policy in Indonesia is argued to bring more challenges in implementing the decentralization and community-based approaches in coastal zones. The lessons learned in this study provide insight in how far decentralized coastal zone management has taken place in Malaysia and Indonesia. The significant differences in the pattern of coastal zone management in these two countries are discussed in detail. This study recognizes that co-management and community-based approaches can be appropriate in dealing with coastal zone management. This comparative perspective is important to the development of a bigger picture of sustainable coastal zone management processes and cross-regional knowledge-sharing in Southeast Asia.     

影响中国沿海雾中航行的环境因素及对策

该文对影响中国沿海雾中航行的环境因素进行了分析研究，提出了改善中国沿海航行环境的基本对策以及中国沿海雾中航行注意事项。对于保证船舶雾中航行安全，防止事故发生，具有重要意义。     

Exploring the effects of passenger rail franchising in Britain: Evidence from the first two rounds of franchising (1997-2008)

This paper provides an up-to-date review of the previous literature concerning the impact of passenger rail franchising on productivity and costs in Britain, and also presents important new evidence. In particular, the extension in time of previously-used datasets offers the first opportunity to study the impacts of re-franchising. The previous literature emphasised the failure of franchising to produce sustained productivity gains, with a sharp deterioration in productivity after 2000. The new evidence presented offers a somewhat more positive view of the British experience. It suggests that part of what was previously considered to be falling productivity may in fact be due to exogenous changes in diesel prices. Further, new data suggests that the recent increases in costs have resulted in higher quality of service. Finally, competitive re-franchising, and the associated unwinding of short-term management and re-negotiated contracts, seems to have led to improvements in productivity between 2006 and 2008. Nevertheless, it remains the case that passenger rail franchising in Britain has failed to reduce costs in the way experienced in many other industries and in rail in other European countries. The evidence is that somewhat larger franchises, avoiding overlapping and optimising train density and length, should reduce costs. We also speculate that the major increase in wages and conditions of staff might be moderated by longer franchises, although that remains to be proved. This re-appraisal of the British case is important in the context of the wider international interest in the use of franchising in passenger rail, and its relevance to the current review of ways of introducing competition into the domestic rail passenger market in Europe.     

东海大桥基础沉桩施工

东海大桥是我国第一座真正意义上的跨海大桥,所采用的打入桩不仅直径和长度大,而且数量多,为国内工程所罕见。文章全面介绍在自然条件恶劣的外海进行沉桩施工的情况。     

箱型船模底部板架流固耦合振动试验研究

对钢质箱型船模底板及板架进行了干模态和湿模态试验,通过试验结果和计算结果的比较,得出对工程计算中如何处理舱内水问题的相关结论。     

UNCTAD activities in the field of ports and their future

UNCTAD's work in the field of ports started, soon after its establishment in 1964, as a result of a 'Common measure of understanding on shipping questions'. It resulted in a three pronged effort in research, training and technical assistance, carried by the secretariat in close collaboration with the industry. Technical publications were published and are widely used by practitioners throughout the world. Port managers and government officials responsible for ports in developing countries were the beneficiaries of large-scale training programmes. Technical assistance to improve port services was conducted in several developing countries. During the 1990s, new mandates were agreed in the field of transport in which ports are not explicitly mentioned. This paper argues that the stakes in ports are so vital for trading countries, notably those seeking accelerated economic development, that a broad interpretation of the current mandate is needed.     

参观香港冬季国际游艇展览有感

2005年12月3日-4日香港举办了新一届冬季国际游艇展览会，这是2005年香港举办的第二个国际游艇展。香港一向实行自由贸易的市场运作机制，绝大部分的国际展览活动都交由民间的私人商业机构来举办。在游艇展览方面，香港政府引入两家私人机构同年举办国际游艇展览会，意在繁荣活跃香港的水上活动。早在2005年4月初，香港西部的黄金海岸游艇会就举办了香港第8届国际游艇展览会。才过去半年时间，12月份香港政府又在香港东部西贡的匡湖居游艇会办展，     

港口集装箱起重机钢丝绳使用情况调查与分析

24个码头的 5 0 0多台集装箱起重机的钢丝绳使用情况表明 ,国内港口所用钢丝绳的品牌规格较多 ,其中日本产品和国内产品的市场占有率较高 ,国内产品的消耗量最大 ;进口产品的性能普遍较好 ,而国内产品则性能质量差异较大 ,除少数品牌外 ,使用寿命较短 ;各国内部品牌之间的价格接近 ,欧洲产品价格最高 ,国产品牌价格低廉     

我国老港区改造模式分析

随着我国沿海地区经济持续快速发展，许多沿海港口同时面临着新港区的开辟与老港区的改造。对老港区存在的问题进行总结归纳，结合案例分析探讨我国老港区的改造模式与思路。