Determination of attainable regions in ship maneuvers: an application of differential inclusions to the modeling of ship dynamics

A commonly used mathematical tool in vehicle dynamics simulation is the ordinary differential equation. However, in some situations, these equations may not be sufficient to solve problems. For robust flight, surface ship or submarine control design, safety assessment, missile and aircraft guidance, the influence of disturbances, and differential games of pursuit–evasion, more versatile tools are needed. The differential inclusion (DI) is a generalization of a differential equation that can be extremely useful. The solution of a DI is not just a model trajectory or a set of trajectories obtained by a randomization of the original problem. The solution is a reachable set, and it is a deterministic object. A differential inclusion solver and its application to vessel movement are described. Compared to previous publications on the DI solver, the new feature is an implementation of the fuzzy sets technique to improve the resulting images. It is pointed out that the reachable sets cannot be assessed properly while treating the uncertain variables as random. The application of the DI solver can give a proper view of the regions in the state space where all the possible model trajectories belong.     

隧道塌方区的施工处理与有限元分析

通过分析云湖隧道施工中的塌方原因,并结合具体的工程情况,对塌方区采用双排注浆小导管加固及采用双侧壁导坑法施工。在塌方处理段增设监测断面,利用有限元法进行数值模拟分析,得出现场监控数据与有限元分析结果基本一致,且在规范允许的范围内。     

Novel Manufacturing Technology of Hyperbolic Plates for Shipbuilding

On the basis of the principle of dieless hydrobulging technology, a novel hydrobulging technology for manufacturinghyperbolic plates is proposed. First, a toroidal pipe elbow or a partial toroidal pipe elbow is formed, then the single hydrobulgedstructure can be cut up into some desired plates. It is proved by experiments and finite element simulation that manufacturingtechnology of hyperbolic plates adopting integrated hydrobulging forming technology is feasible.     

Internet-based Teleoperation Platform For Mobile Robot

An Internet-based teleoperation platform for Mobile Robot is introduced in this paper. The hardware of the system mainly consists of a mobile robot. Its software employs client-server architecture for robot control and feedback information display . Different communication protocols are adopted according to the characteristics of message exchanged between the robot server and the client. The user interface is designed for the purpose of interaction. The great benefit of this client-server architecture is that the client software is insulated from the lowest level details of the mobile robot. Thus, it is very easy to implement and test new advanced teleoperation control algorithms, interface designs and applications on this platform without large programming work.     

Application of ML to System Identification for Underwater Vehicle

In this paper, maximum-likelihood (ML) and its relaxation algorithm, which are used to identify the mathematicsmodel of an underwater vehicle(UV), arc discussed. With the trial data of zigzag tests, the hydrodynamic derivatives of theUV were estimated, and the relaxation algorithm is confirmed to have better astringency from the contrast between the twomethods.Then a simulation environment based on these parameters is established to verify the validity and effect of these meth-ods. The result shows the model is credible and the methods are very useful for the research of maneuverability and adaptivecontrol of underwater vehicles.     

移居高原罹患矽肺矿工20年心血管X线改变的动态观测

选择移居2500m高原63名矽肺矿工，连续20年摄后前位胸片，按居住年限分组，自身对照，观察矽肺与肺动脉高压的演变过程．分析矽肺X线心血管4项指标的改变。结果表明：动态观察矽肺X线及心血管各指标的改变，对预测高原人体矽肺的发生，评定矽肺的发展程度，观察疗效和对矽肺愈后判定有着非常重要的临床应用价值。     

FEA for designing of floating raft shock-resistant system

Choosing the equipment with good shock-resistant performance and taking shock protection measures while designing the onboard settings, the safety of onboard settings can be assured when warships, especially submarine subjected to non-contact underwater explosion, that is, these means can be used to limit the rattlespace (i. e. , the maximum displacement of the equipment relative to the base) and the peak acceleration experienced by the equipment. Using shock-resistant equipments is one of shock protection means. The shock-resistant performance of the shock-resistant equipments should be verified in the design phase of the equipments. The FEA (finite element analysis) software, for example, MSC. NASTRANw, can be used to verify the shock-resistant performance. MSC. PATRAN and MSC. NASTRAN are used for modeling and analyzing the floating raft vibration isolating equipment. The model of the floating raft and the floating raft vibration isolating system are theoretically analyzed and calculated, and the analysis results are in agreement with the test results. The transient response analysis of the system model follows the modal analysis of the floating raft vibration isolating system. And it is used to verify the shock-resistant performance. The analysis and calculation method used in this paper can be used to analyze the shock-resistant performance of onboard shock-resistant equipments.     

烟大航线客滚运输中危险化学品管理的探析

目前,航行于渤海湾的客滚船非常多,为货物运输、人民出行提供了极大的方便,大连至烟台、威海等地的航线被称为"黄金水道"。但滚装客船在为人们提供便捷的同时,其特有的风险也逐步显现,如果这类船舶运输化学品,极易引发灾难性事故。本文就如何做好客滚运输中危险化学品安全管理工作,从我国危险品监督管理现状、滚装客船运输化学品目前的管理等方面进行了分析、研究,并针对存在的提出了相关的管理建议。     

变形钢筋与活性粉末混凝土的粘结性能试验研究

通过不同直径和不同埋长的普通热轧变形钢筋活性粉末混凝土的钢筋拔出试验,研究变形钢筋与活性粉末混凝土的粘结性能及粘结—滑移的本构关系。研究表明:活性粉末混凝土与钢筋的极限粘结应力随着钢筋直径的增加而下降,钢筋直径相同时随着锚固长度的增加而降低。提出普通热轧变形钢筋与活性粉末混凝土的极限粘结强度与锚固长度的计算公式。运用该计算公式得出,直径为14和16 mm钢筋的锚固长度适宜取3倍钢筋直径,直径为18 mm钢筋的锚固长度适宜取4倍钢筋直径。根据试验数据回归出基于相对保护层厚度和相对有效粘结长度的极限粘结应力计算公式和粘结应力与滑移的本构关系式。