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Unmanned Ship Identification Based on Improved YOLOv8s Algorithm
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作者 Chun-Ming Wu Jin Lei +2 位作者 Wu-Kai Liu Mei-Ling Ren Ling-Li Ran 《Computers, Materials & Continua》 SCIE EI 2024年第3期3071-3088,共18页
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 ... 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%. 展开更多
关键词 Unmanned ships R_YOLO EMA CsPstage YOLOv8s
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海浪扰动下电液3-UPS/S舰船并联稳定平台振动特性分析
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作者 袁晓明 王维锜 +2 位作者 张睿聪 周如林 张立杰 《液压与气动》 北大核心 2023年第10期1-14,共14页
针对电液驱动的舰船并联稳定平台在实际工况下的振动问题,以电液3-UPS/S舰船并联稳定平台为研究对象,在考虑铰链刚度的基础上应用虚功原理建立稳定平台的动力学模型;通过海浪谱函数,计算了随机海浪激励下船舶的运动响应,进而得到稳定平... 针对电液驱动的舰船并联稳定平台在实际工况下的振动问题,以电液3-UPS/S舰船并联稳定平台为研究对象,在考虑铰链刚度的基础上应用虚功原理建立稳定平台的动力学模型;通过海浪谱函数,计算了随机海浪激励下船舶的运动响应,进而得到稳定平台跟踪舰船运动的响应规律;分析了稳定平台在随机海浪激励条件下和初始工作空间内的固有频率变化特性;最后,为验证动力学模型的正确性,采用脉冲激励法对稳定平台样机进行模态试验,固有频率理论值与试验值的最大误差为4.66%,可以验证动力学模型的正确性。 展开更多
关键词 电液3-UPs/s舰船并联稳定平台 海浪模拟 动力学方程 振动特性 模态试验
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洋山港VTS报告船舶流的统计特性
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作者 刘超 《山东交通学院学报》 CAS 2023年第1期102-109,共8页
为分析某水域船舶流特征和运行规律,量化研究船舶流到港规律,为港口营运和船舶交通管理(vessel traffic services, VTS)提供数据支持,以洋山港水域2020年66 d内连续的1387条VTS实测船舶流记录数据为统计样本,基于矩估计理论的K-S检验和... 为分析某水域船舶流特征和运行规律,量化研究船舶流到港规律,为港口营运和船舶交通管理(vessel traffic services, VTS)提供数据支持,以洋山港水域2020年66 d内连续的1387条VTS实测船舶流记录数据为统计样本,基于矩估计理论的K-S检验和χ^(2)检验,从拟合最优的角度对船舶到港情况进行参数估计。结果表明,洋山港水域VTS报告的船舶在8、9月的船舶流样本服从正态分布,7月船舶流样本不服从泊松分布和正态分布,证明船舶流的分布特征随环境和时间因素变化显著,仅采用泊松分布或正态分布并不能全面描述水域交通流特征。相关研究结论可为船舶流特征分析、通航调度等相关研究提供借鉴和参考。 展开更多
关键词 正态分布 泊松分布 K-s检验 χ^(2)检验 船舶流
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A Non-geometrically Similar Model for Predicting the Wake Field of Full-scale Ships 被引量:1
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作者 Chunyu Guo Qi Zhang Yu Shen 《Journal of Marine Science and Application》 CSCD 2015年第3期225-233,共9页
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... 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. 展开更多
关键词 wake field full-scale ships non-geometrically similar model scale effect KRIsO’s container ship (KCs
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Experimental Investigation of the Decay from A Ship’s Propeller 被引量:1
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作者 W.Lam G.A.Hamill +2 位作者 宋永臣 D.J.Robinson S.Raghunathan 《China Ocean Engineering》 SCIE EI 2011年第2期265-284,共20页
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.... 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. 展开更多
关键词 ship's propeller jet Laser Doppler Anemometry (LDA) maximum velocity decay
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Fuzzy Optimal Control Design for Ship Steering
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作者 EJAZ Muhammad CHEN Mou 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第3期459-467,共9页
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 ... 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. 展开更多
关键词 Takagi sugeno(T s) fuzzy modeling OPTIMAL control OPTIMAL linear QUADRATIC TRACKER (LQT) ship sTEERING
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Powership's Identity and MARPOL Convention Application
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作者 Vehbi S Ataergin 《Journal of Shipping and Ocean Engineering》 2015年第4期203-218,共16页
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 s... 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. 展开更多
关键词 Maritime ship power MARPOL shipowner's liability pollution sEWAGE garbage.
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Calculate Thermal Infrared Intensity of the Hull’s Military Ship
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作者 Ramin Ebrahimi Laleh Nima Ghasemloo 《Journal of Geographic Information System》 2014年第4期317-329,共13页
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... 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. 展开更多
关键词 INTENsITY Radiation THERMAL Infrared THERMAL DETECTOR Geometry’s MILITARY ship NEURAL
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China's Shipping Market
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作者 Zhong Ri 《China's Foreign Trade》 1994年第5期20-21,共2页
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 t... 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 展开更多
关键词 LINE China’s shipping Market
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A Full Mission Simulator of the Ship's Automated Electric Power System for Training and Competence Testing of Marine Engineers
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作者 Mykola Mukha 《Journal of Shipping and Ocean Engineering》 2017年第4期153-160,共8页
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 m... 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. 展开更多
关键词 Full mission simulator ship's automated electric power system practical training and proficiency testing training coursessubjects.
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Shipping Giant Launches New Line between Tianjin,U.S East Coast
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《China's Foreign Trade》 2007年第14期27-27,共1页
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.
关键词 shipping Giant Tianjin U.s East coast grand alliance
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Granny's Ship
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作者 谢琼 Dorothy Dunn 《英语知识》 2000年第1期19-,共1页
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 mos... 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 展开更多
关键词 Granny’s ship
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和平海运与HACHIMAN SHIPPING S.A.等船舶碰撞损害赔偿纠纷案
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作者 汪洋 《航海》 2002年第3期30-32,共3页
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... 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. 展开更多
关键词 HACHIMAN shipPING s.A. 船舶碰撞损害赔偿纠纷案 汕头市和平海运有限公司 海上安全 海事特别诉讼法 海商法
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The Cradle of China's First Class Seafarers:Qingdao Ocean Shipping Mariners College——by Lin Jinhe,President of Qingdao Ocean Shipping Mariners College
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《中国远洋航务》 1998年第11期18-19,共2页
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... 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- 展开更多
关键词 by Lin Jinhe President of Qingdao Ocean shipping Mariners College The Cradle of China’s First Class seafarers
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REGULATIONS OF THE PEOPLE'S REPUBLIC OF CHINA GOVERNING REGISTRATION OF SHIPS
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《中国远洋航务》 1995年第6期34-36,共3页
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 char... 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 展开更多
关键词 REGULATIONs OF THE PEOPLE’s REPUBLIC OF CHINA GOVERNING REGIsTRATION OF ships
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REGULATIONS OF THE PEOPLE'S REPUBLIC OF CHINA GOVERNING REGISTRATION OF SHIPS
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《中国远洋航务》 1995年第5期41-42,共2页
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 th... 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 展开更多
关键词 REGULATIONs OF THE PEOPLE’s REPUBLIC OF CHINA GOVERNING REGIsTRATION OF ships
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30 m宽隧洞内万吨级货船拖曳通航船周水位分布特性试验研究
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作者 吴俊 王伟 +1 位作者 周世良 程小龙 《水道港口》 2024年第5期708-715,共8页
通航隧洞作为穿越山体的隐蔽航道,对于隧洞通航水力条件而言,水位则是影响超限性航道通航的关键因素。为探究货船在通航隧洞内拖曳航行时船周水位变化规律及由水位变化引起的航行水力特性。建立了1:40包含隧洞及隧洞顶部船舶拖曳装置物... 通航隧洞作为穿越山体的隐蔽航道,对于隧洞通航水力条件而言,水位则是影响超限性航道通航的关键因素。为探究货船在通航隧洞内拖曳航行时船周水位变化规律及由水位变化引起的航行水力特性。建立了1:40包含隧洞及隧洞顶部船舶拖曳装置物理模型试验系统,开展了不同水深工况下5级拖曳速度物理试验,重点探讨了2倍船长范围内船前后水位变化情况、影响水位波动的因素以及船舶纵倾角度变化。研究结果表明:拖曳速度的增加导致船前水位升高和船后水位下降,但在适度拖曳速度范围内(0.5~1.5 m/s),水位变化较小,提高通航的安全性;增加隧道水深可减小船前水位升高和船后水位下降的幅度,尤其在水深6~8 m范围内,水位变化较小,改善通航条件;随着拖曳速度的增加,船舶的纵倾角度增大,而随着隧道水深的增加,纵倾角度减小,适度控制拖曳速度在水深6~8 m的范围内有助于减小船体的纵倾角度,提高通航的稳定性和安全性。研究结果可为通航隧道船舶拖曳通航关键技术提供重要的参考和借鉴。 展开更多
关键词 通航隧洞 模型试验 水力特性 船周水位
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成组法疲劳试件个数选取方法研究
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作者 张凡 王艺陶 +1 位作者 王丹 竺一峰 《装备环境工程》 CAS 2024年第1期74-80,共7页
目的 在成组法疲劳试验过程中,确定最少疲劳试件个数判据,获取有效可靠的疲劳试验结果。方法基于疲劳可靠性的基本原理,在疲劳寿命对数正态分布的假设下,根据t分布理论,结合船舶及海洋工程一般构件具有95%置信度和可靠度p=97.72%下的P-... 目的 在成组法疲劳试验过程中,确定最少疲劳试件个数判据,获取有效可靠的疲劳试验结果。方法基于疲劳可靠性的基本原理,在疲劳寿命对数正态分布的假设下,根据t分布理论,结合船舶及海洋工程一般构件具有95%置信度和可靠度p=97.72%下的P-S-N曲线的基本要求,推算出相应置信度和可靠度下5%误差限度内的疲劳试件个数与允许的最大变异系数数值的对应关系,以此作为成组法疲劳试验最少试件个数的判据,开展典型节点的疲劳试验。结果 得到了具有95%置信度的百位估计值Np,并通过线性相关系数r,判断对数疲劳应力Y=lg S与X=lg Np之间线性相关的程度,采用最小二乘法对对数疲劳寿命lg Np和对数疲劳应力lg S进行线性拟合,得到了具有95%置信度的P-S-N曲线,与IIW规范中相应的曲线一致。结论 文中给出的成组法疲劳试验个数确定方法是合理、可靠的,为船舶与海洋工程结构物典型焊接接头成组法疲劳试验个数的确定提供了依据。 展开更多
关键词 试件个数 P-s-N曲线 变异系数 疲劳可靠性 成组法 疲劳试验 船舶结构
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综合C/S和B/S模式的船舶信息管理系统 被引量:14
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作者 耿俊豹 梁乾 +1 位作者 魏曙寰 金家善 《计算机工程》 EI CAS CSCD 北大核心 2005年第13期215-216,230,共3页
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... 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。 展开更多
关键词 船舶 信息管理系统 客户端/服务器 浏览器/服务器 JAVA语言
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基于D-S证据理论的舰船技术状态评估方法 被引量:14
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作者 耿俊豹 黄树红 +1 位作者 金家善 刘伟 《舰船科学技术》 北大核心 2006年第3期99-102,共4页
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... 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。 展开更多
关键词 舰船 技术状态 D-s证据理论 不确定性
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