System Identification Modeling of Ship Manoeuvring Motion in 4 Degrees of Freedom Based on Support Vector Machines

Based on support vector machines, three modeling methods, i.e., white-box modeling, grey-box modeling and black-box modeling of ship manoeuvring motion in 4 degrees of freedom are investigated. With the whole-ship mathematical model for ship manoeuvring motion, in which the hydrodynamic coefficients are obtained from roll planar motion mechanism test, some zigzag tests and turning circle manoeuvres are simulated. In the white-box modeling and grey-box modeling, the training data taken every 5 s from the simulated 20°/20° zigzag test are used, while in the black-box modeling, the training data taken every 5 s from the simulated 15°/15°, 20°/20° zigzag tests and 15°, 25° turning manoeuvres are used; and the trained support vector machines are used to predict the whole 20°/20° zigzag test. Comparisons between the simulated and predicted 20°/20° zigzag tests show good predictive ability of the proposed methods. Besides, all mathematical models obtained by the proposed modeling methods are used to predict the 10°/10° zigzag test and 35° turning circle manoeuvre, and the predicted results are compared with those of simulation tests to demonstrate the good generalization performance of the mathematical models. Finally, the proposed modeling methods are analyzed and compared with each other in aspects of application conditions, prediction accuracy and computation speed. The appropriate modeling method can be chosen according to the intended use of the mathematical models and the available data needed for system identification.

Unmanned Ship Identification Based on Improved YOLOv8s Algorithm

Aiming at defects such as low contrast in infrared ship images,uneven distribution of ship size,and lack of texture details,which will lead to unmanned ship leakage misdetection and slow detection,this paper proposes an infrared ship detection model based on the improved YOLOv8 algorithm(R_YOLO).The algorithm incorporates the Efficient Multi-Scale Attention mechanism(EMA),the efficient Reparameterized Generalized-feature extraction module(CSPStage),the small target detection header,the Repulsion Loss function,and the context aggregation block(CABlock),which are designed to improve the model’s ability to detect targets at multiple scales and the speed of model inference.The algorithm is validated in detail on two vessel datasets.The comprehensive experimental results demonstrate that,in the infrared dataset,the YOLOv8s algorithm exhibits improvements in various performance metrics.Specifically,compared to the baseline algorithm,there is a 3.1%increase in mean average precision at a threshold of 0.5(mAP(0.5)),a 5.4%increase in recall rate,and a 2.2%increase in mAP(0.5:0.95).Simultaneously,while less than 5 times parameters,the mAP(0.5)and frames per second(FPS)exhibit an increase of 1.7%and more than 3 times,respectively,compared to the CAA_YOLO algorithm.Finally,the evaluation indexes on the visible light data set have shown an average improvement of 4.5%.

Abnormal Systemic and Ocular Responses to the Valsalva Manoeuvre in Primary Open-Angle Glaucoma:A Case for Autonomic Failure?

Objective This study aimed to examine the association of primary open-angle glaucoma(POAG)with autonomic dysfunction by assessing the differences in systemic and ocular responses to an autonomic provocation test,the Valsalva manoeuvre(VM),between POAG patients and normal subjects.Methods Forty POAG and forty control subjects were subjected to the VM.Systemic and ocular parameters were measured at baseline,phase 2,and phase 4 of the VM(VM2 and VM4),where VM2 and VM4 are sympathetic and parasympathetic nervous activation states,respectively.Heart rate variability was used to assess the autonomic nervous activity,among which the high-frequency component(HF)and the low-frequency(LF)/HF ratio were used as indices of parasympathetic and sympathetic activation,respectively.Results POAG patients demonstrated higher sympathetic activation(LF/HF ratio median:2.17 vs.1.53,P=0.000)than controls at baseline and exhibited attenuated sympathetic and parasympathetic responses(a smaller change in LF/HF and HF values)during the VM than controls.During VM,the intraocular pressure(IOP),mean blood pressure(MAP),mean ocular perfusion pressure(MOPP),and the Schlemm’s canal area(SCAR)increased from baseline to VM2 and then decreased from VM2 to VM4 in both the POAG and control groups(all P<0.05).However,when we compared the changes above,the fluctuations in IOP,MAP,and MOPP were more pronounced in POAG than in controls(all P<0.05),while the changes in amplitudes of SCAR were smaller in POAG(P<0.05).Furthermore,from VM2 to VM4,the choroid thickness(ChT)in the POAG group was significantly decreased,while it was unchanged in normal subjects(P=0.258).A regression analysis showed a significant correlation of the baseline LF/HF with IOP change values(ΔIOP)from baseline to VM2 in POAG(R^(2)=0.147,P=0.014).Conclusion Patients with POAG showed more pronounced fluctuations in IOP,MAP,MOPP and ChT during the VM than controls.These reactions could be associated with autonomic dysfunction in POAG.

A Non-geometrically Similar Model for Predicting the Wake Field of Full-scale Ships

The scale effect leads to large discrepancies between the wake fields of model-scale and actual ships, and causes differences in cavitation performance and exciting forces tests in predicting the performance of actual ships. Therefore, when test data from ship models are directly applied to predict the performance of actual ships, test results must be subjected to empirical corrections. This study proposes a method for the reverse design of the hull model. Compared to a geometrically similar hull model, the wake field generated by the modified model is closer to that of an actual ship. A non-geometrically similar model of a Korean Research Institute of Ship and Ocean Engineering （KRISO）’s container ship （KCS） was designed. Numerical simulations were performed using this model, and its results were compared with full-scale calculation results. The deformation method of getting the wake field of full-scale ships by the non-geometrically similar model is applied to the KCS successfully.

Experimental Investigation of the Decay from A Ship’s Propeller

In the present study, an experimental investigation of the decay of the maximum velocity and its turbulent characteristics behind a ship propeller, in ＂bollard pull＂ condition （zero speed of advance）, is reported. Velocity measurements were performed in laboratory by use of a Laser Doppler Anemometry （LDA） measurement system. Earlier researchers described that the maximum axial velocity is constant at the initial stage of a ship＇s propeller jet （Fuehrer and Romisch, 1977; Blaauw and van de Kaa, 1978; Berger et al, 1981; Verhey, 1983） as reported in a pure water jet （Albertson et al., 1950; Lee et al., 2002; Dai, 2005）, but a number of researchers disagreed with the constant velocity assumption. The present study found that the maximum axial velocity decays in the zone of flow establishment and the zone of established flow with different rates. The investigation provides an insight into the decays of both the maximum velocity and the maximum turbulent fluctuation in axial, tangential and radial components and the decay of the maximum turbulent kinetic energy. Empirical equations are proposed to allow coastal engineers to estimate the jet characteristics from a ship＇s propeller.

Fuzzy Optimal Control Design for Ship Steering

This paper presents a method to design a control scheme for nonlinear systems using fuzzy optimal control.In the design process,the nonlinear system is first converted into local subsystems using sector non linearity approach of Takagi Sugeno(T S)fuzzy modeling.For each local subsystem,an optimal control is designed.Then,the parameters of local controllers are defuzzified to construct a global optimal controller.To prove the effectiveness of this control scheme,simulations are performed using the mathematical model of Esso Osaka tanker ship for set point regulation with and without disturbance and reference tracking.In addition,the simulation results are compared with that of a PID controller for further verification and validation.It has been shown that the proposed optimal controller can be used for the nonlinear ship steering with good rise time,zero steady state error and fast settling time.

基于LSTM-RNN的船舶操纵运动黑箱建模

当无需揭示船舶操纵运动机理过程,而只需对输入输出建立映射时,黑箱建模成为一种有效途径。本文基于长短期记忆-循环神经网络(Long Short-term Memory-recurrent Neural Network,LSTM-RNN)构建船舶航向-舵角黑箱模型,LSTM网络为10-10-1结构,误差指标为RMSE,参数学习采用Adam算法。开展实船Z型操纵实验获取了航向-舵角数据。前70%用于模型训练,后30%用于模型测试。训练后的模型使得RMSE达到设计目标。对测试集数据,训练后模型拟合优度在0.98以上,表明其具有良好的有效性和泛化性。文中航向-舵角LSTM-RNN黑箱模型结构简明清晰,参数明确,易于实际操作使用,为航向-舵角关系建模提供了一种可行方法。

Powership＇s Identity and MARPOL Convention Application

The concept, although it is not new, came to surface in the last ten years with significant technological improvement and became a temporary solution for the port cities where the supply of electricity is in need. A ship shaped floatable structure with a huge power generator on board becomes the temporary but effective solution. However, these converted ex-ships are still legally ships in order to admit them sufficiently within the scope of a leading convention, which applies to marine and air pollution from ships. This issue needs research on the legal definition of the ＂ship＂ to clarify if it is a ship and to determine whether that would also fall within the concept of MARPOL.

Calculate Thermal Infrared Intensity of the Hull’s Military Ship

Stealth technology emphasizes on the reduction in reflection and radiation energies, the surface of target's body in the range of visual, radar, thermal and near IR and so on. Providing solutions to reduce thermal IR intensity radiation is one of the appropriate actions in passive defense for identifying power and targeting enemy. Therefore, questions are brought up: How much is the thermal IR intensity radiation of surface of the hall’s vessel? How much is the effect of each parameter? This thesis tries to provide the software to answer these questions. The provided software measures thermal IR intensity radiation of the surface of the hall’s vessel by the material substance, the temperature of the surface of the hall’s vessel, the situation and characteristic of the thermal detector, noticing the coefficient of environment atmospheric transmittal. This software by changing the effective parameters on thermal IR radiation calculates the thermal radiation on thermal detector in different situations.

China's Shipping Market

Since the New China, the nation’s ports have been under the centralized control and development program of the Ministry of Traffic, with a separate shipping line. With the growth of the national economy and foreign trade after reform and opening to the outside world, it has become more evident that construction of coastal ports has lagged behind. To catch up, China is opening

A Full Mission Simulator of the Ship＇s Automated Electric Power System for Training and Competence Testing of Marine Engineers

This article describes practical preparation of marine engineers on the full mission simulator complex of the ship＇s automated electrical power plant. A full mission simulator complex of the ship＇s automated power management system meets International Convention STCW （Standards of Training, Certification and Watchkeeping） 78 （with Manila amendments 2010） requirements in part of adequate reproduction of its operational modes corresponding to the actual configuration and layout of the ship＇s automated power management system with real consumers and typical loads. The simulator is fully consistent with the goals and objectives of the practical training, as well as the goals and objectives of proficiency testing engine department officers on issues of technical maintenance of real ship＇s equipment （high voltage installations included） and means of automation. The simulator＇s complex is designed for training and proficiency testing of cadets and students of maritime educational institutions, as well as training and proficiency testing of marine specialists （mechanics and electricians） by watch-keeping and maintenance of modem integrated automated control systems of ship＇s electric power plant and the individual ship electromechanical systems, including high-voltage systems. A simulator＇s complex provides adequate reproduction of operational situations on technical side of real ship electric and automation equipment provides training on monitoring, control and management diesel-generator sets in hand, semi-automatic and automatic modes of power station, control and management of electromechanical systems, as well as the set of tasks upon parameterization, visualization and etc. Besides number of combinations of monitoring, control and management tasks, the simulator＇s complex provides an opportunity to simulate various practical fault conditions. It allows students to focus on the work of automatic control system in emergency situations and to work out correct actions for a watch-keeper on searching, localizing of faults and troubleshooting of equipment.

Shipping Giant Launches New Line between Tianjin,U.S East Coast

The Grand Alliance group, one of the world＇s shipping giants, has launched a new route betweennorth China＇s port city of Tianjin and the U.S. east coast.

PERFORMANCE EVALUATION OF SHIPPING CONTAINER POTENTIALS FOR NET-ZERO RESIDENTIAL BUILDINGS

Recycled shipping containers have the potential to be successfully used as a net-zero ready home.This study aims to evaluate the outcomes of a high-performance shipping container single-family housing project located in Virginia Beach,Virginia.The project was awarded the Best Undergraduate Project in the Single-family division at the 2019 U.S.Department of Energy’s Solar Decathlon Design Challenge.The Hampton University Millennial Village Design Team designed a marketable net-zero ready container home for the ViBe Creative District in Virginia Beach,Virginia.Container Homes are not suitable for every homeowner,but they have a particular appeal to a generation of young and creative people across the country.For many municipalities in Virginia,where container housing is not readily accepted,the ViBe creative district has been having discussions with City code officials and local architects about the benefits.The Hampton University Millennial Village Design Team aimed to take advantage of the competition as an opportunity to explore a building construction method that is not widely seen in this part of the country.Testing design for net-zero readiness is a comprehensive way to understand how this type of construction performs from a building science standpoint.Collaboration with professional industry advisors helped the team to use research-based design methods to work on a unique project that the team believes will become a reality in the future.For the performance assessment of a net-zero container house,several simulation tools were used to investigate the environmental impacts,daylight performance,envelope performance,Energy Use Intensity(EUI),Home Energy Rating System(HERS),and solar energy generation.As for energy standards and codes,the Virginia residential code(VRC)2015,International Energy Conservation Code(IECC)2015 and The American Society of Heating,Refrigerating and Air-Conditioning Engineers(ASHRAE)90.1-2013 for residential buildings were consulted to set each variable for the net-zero container house project.The Rem/Rate energy simulation software achieved the HERS index of 51 and 0 without and with the applications of roof photovoltaics,respectively.

Granny's Ship

Throughout~*the Depression years^1,mybrothers,sisters and I often heard our grannysay,“One of these days,my ship is comingin.”Of course Granny s ship was just a~*dream—her escape from the reality of beingpoor^2 most of her life.But to us it was veryreal.~*Our family got by with the barest of ne-cessities;there rarely was enough left over forspecial desires.~3 So if we wished for

和平海运与HACHIMAN SHIPPING S.A.等船舶碰撞损害赔偿纠纷案

一、当事人名称 原告汕头市和平海运有限公司. 被告HACHIMAN SHIPPING S.A.. 被告DORVAL KAIUN K.K.. 二、当事人诉辨 原告汕头市和平海运有限公司诉称,2000年7月3日,原告所属"和平"轮在长江口水域正常出口航行时,相向行驶的被告所属"金亚马"轮突然违章穿越航道,在"和平"轮的正常水道上碰撞了"和平"轮的首部,造成船艏左舷严重受损,原告营运被迫中止,损失达90万元人民币.原告认为,本起事故是由于"金亚马"轮违章航行穿越航道避让措施严重不当所致,被告对此应负90%的责任.据此,原告向本院起诉,请求判令两被告赔偿原告经济损失人民币81万元及利息,并承担诉讼费用及律师费用.

The Cradle of China's First Class Seafarers:Qingdao Ocean Shipping Mariners College——by Lin Jinhe,President of Qingdao Ocean Shipping Mariners College

Qingdao Ocean Shipping Mariners College is a College subordinate to China Ocean Shipping (Group) Company under the Ministry of Communications. In our college there are the Department of Marine Navigation,Department of Marine Engineering, Department of Shipping Management and Department of Foreign Languages, offering speciahies of Marine Navigation, Marine Engine Control, Marine Electrical Equipment Control, Marine Radio Communication, International Shipping Management and International Finance and Accounting. We have 3 types of education: the education of formal college schooling, the training for implementation of the 95 revised STCW Convention and the continuation education. Meanwhile we undertake different training of COSCO’s contracted seafarers overseas and other managerial per-

REGULATIONS OF THE PEOPLE'S REPUBLIC OF CHINA GOVERNING REGISTRATION OF SHIPS

Chapter Ⅴ Registration of Bareboat Charter Article 25 In any of the following cases,the shipowner and the charterer shall apply for the registration of barehoat charter: a. A ship of Chinese nationality hareboat chartered to a Chinese enterprise; b. A ship of foreign nationality hareboat chartered to a Chinese enterprise; c. A ship of Chinese nationality

REGULATIONS OF THE PEOPLE'S REPUBLIC OF CHINA GOVERNING REGISTRATION OF SHIPS

Chapter Ⅲ Nationality of Ships Article 15 A shipowner applying for the nationality of a ship shall, in addition to the Certificate of Registration of Ship’s Ownership, submit the following docu-ments according to the ship’s navigation zone: 1. For ships engaged in international voyages, the valid technical documents of the ship issued by an authorized organization for survey of ships in accordance with

综合C/S和B/S模式的船舶信息管理系统

分析和比较了信息管理系统(MIS)开发中的客户端/服务器(C/S)和浏览器/服务器(B/S)模式的特点,以及Java语言的跨平台的优势。针对船舶的特点,提出了基于Java的综合C/S和B/S模式的设计体系。经在某船舶信息管理系统的开发、应用和测试,证明该设计体系对于船舶类的信息管理系统是可行、实用和科学的,值得其它类似信息管理系统加以借鉴。

基于D-S证据理论的舰船技术状态评估方法

在简要叙述船舶技术状态评估现状的基础上,提出了基于D-S证据理论的舰船技术状态评估方法。介绍了船舶技术状态评估的重要性和发展现状,以及可处理由不知道所引起的不确定性的D-S证据理论和基于D-S证据理论的决策方法;通过实例详细阐述如何用D-S证据理论进行舰船技术状态评估。实例证明,通过应用D-S证据理论,提高了舰船技术状态评估的准确性和可靠性,降低了评估的不确定性。