The enforcement of shipping standards under UNCLOS

This article discusses the enforcement of shipping standards, with a particular focus on Part XII of UNCLOS. Section 6 of Part XII contains the only comprehensive set of vessel-related enforcement provisions in the Convention, but the Part’s scope is limited to “the preservation and protection of the marine environment.” Therefore, not all shipping standards fall clearly within Part XII’s ambit, including those centered on safety, security, and crewing considerations. The enforcement provisions of Section 6 are favorable to flag states and their vessels, and Section 7 contains a number of safeguards for their benefit, so it is in the interests of these parties to have coastal state enforcement governed by Part XII. However, the ability of coastal states to establish and enforce shipping standards that apply within the territorial sea extends to more than just environmental matters. The result is that different standards give rise to different enforcement powers, depending on the maritime zone in which a vessel is located, even if those standards arise from the same international agreement. It is suggested that to remedy these problems, UNCLOS would need to be amended in order to provide a comprehensive enforcement regime for the enforcement of shipping standards.     

大型汽车滚装船横向挠曲强度全船有限元分析

大型汽车滚装船（PCTC）自身结构的特殊性和横向挠曲强度的关键性，对其进行横向挠曲强度全船有限元分析十分必要。以8000车大型汽车滚装船为研究对象，采用通用软件MSC／PATRAN建立有限元模型．按照ClassNK规范进行载荷的选取和施加，最终得到了横向挠曲强度全船有限元分析结果。对大型汽车滚装船挠曲强度的直接计算有一定的指导作用。     

雷达式液位测量在船舶行业的应用

探讨了雷达式液位测量在船舶行业中的应用.详细介绍了雷达式液位测量系统的原理、计算、特点、组成及应用.在此基础上展望了雷达式液位测量系统在未来船舶行业中的前景.     

奇异积分处理技术在低频声散射数值计算中的应用

针对散射声场的计算问题，将奇异积分处理技术应用于目标的低频声散射的数值计算、理论验模与仿真试验。若果表明，ka＜3时，新方法的仿真结果与解析值以及等价面元近似方法取得了较好的一致；而ka≥3时，新方法的仿真结耙要好于等价面元近似方法。     

适用于高速铁路的计算机联锁测试平台设计

因高速铁路和客运专线的建设需要,计算机联锁系统增加了新的控制功能和外部接口,如正线车站的点灯和灭灯功能,以及与列控系统的安全通信接口等。计算机联锁的新增功能和通信接口直接影响着整个系统的安全性和可靠性。因此,研究科学的、全面的测试方法,设计适合高速铁路的计算机联锁测试平台,对提高计算机联锁系统的安全性、可靠性具有重要的意义。重点对测试平台的结构、测试案例、测试方法等进行了叙述。     

适用于高速铁路的TYJL-ADX型联锁系统的研究与实现

通过对既有TYJL-ADX型计算机联锁系统的分析、结合中国高速铁路对联锁系统的技术需求,说明了在原系统的基础上开发适用于高速铁路的联锁系统的必要性,详细阐述了具体的实现原则及方法,新系统的结构、主要功能,最后总结了新系统的实际应用情况。     

Color image segmentation by edge linking and region grouping

A novel method toward color image segmentation is proposed based on edge linking and region grouping. Firstly, the edges extracted by the Canny detector are linked to form regions. Each of the end points of edges is connected by a direct line to the nearest pixel on another edge segment within a sub-window. A new distance is defined based on the feature that the edge tends to preserve its original direction. By sampling the lines to the image, the image is over-segmented to labeled regions. Secondly, the labeled regions are grouped both locally and globally. A decision tree is constructed to decide the importance of properties that affect the merging procedure. Finally, the result is refined by user’s selection of regions that compose the desired object. Experiments show that the method can effectively segment the object and is much faster than the state-of-the-art color image segmentation methods.     

Efficient democratic group signatures with threshold traceability

Democratic group signature (DGS) is a group-oriented primitive with great flexibilities, i.e., no group manager, anonymity, and traceability. In a DGS scheme with (t, n)-threshold traceability, any subset of not less than t members can jointly reveal the identity of the signer while preserving security even in the presence of an active adversary can corrupt up to t − 1 group members. This paper proposes an efficient DGS scheme. We use publicly verifiable secret sharing (PVSS) to distribute the trapdoor via which the real signer is revealed. The computation cost and communication overhead of our DGS signatures are greatly reduced, compared with the existing work. For example, the size of the resulting signature contains only 2n + 1 elements of Z _q , except the PVSS output.     

一种基于双闭环控制的并联Buck均流器设计

直驱式永磁同步风电系统电机侧变换器的一种常见拓扑结构为二极管整流桥后接Boost斩波电路。此结构具有较强的非线性,采用普通PI控制器很难使系统在正常运行范围内保持较好动态性能。本文基于双闭环控制方法,设计了基于Buck电路的并联均流器,并进行了相关仿真和试验。     

某轻型防护越野车的防弹方案设计

介绍了某轻型防护越野车防弹方案的设计与验证。首先通过数据对比选择了A型钢作为本车的基础防弹材料,再经过计算、实弹验证、工艺验证等手段掌握了A型钢的防弹性能和工艺特性,并在此基础上进行了本车的防弹方案设计。在本文中,以该车正前面部分的防护方案为主体结合车体的轻量化思路,着重介绍了防弹板复合设计、倾角结构效应设计、相应试验验证等内容,最后还针对防弹钢板焊缝处防弹性能下降的现象,介绍了多种相应的处理思路和方法。