The value of form factor k at different drafts is important in predicting full-scale total resistance and speed for different types of ships. In the ITTC community, most organizations predict form factor k using a low...The value of form factor k at different drafts is important in predicting full-scale total resistance and speed for different types of ships. In the ITTC community, most organizations predict form factor k using a low-speed model test. However, this method is problematic for ships with bulbous bows and transom. In this article, a Computational Fluid Dynamics(CFD)-based method is introduced to obtain k for different type of ships at different drafts, and a comparison is made between the CFD method and the model test. The results show that the CFD method produces reasonable k values. A grid generating method and turbulence model are briefly discussed in the context of obtaining a consistent k using CFD.展开更多
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
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
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
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
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
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
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
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
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.
The People＇s Republic of China Social Insurance Law （draft） has undergone three readings at the Standing Committee of the National People＇s Congress. The Law, once promulgated, will be of great significance to imp...The People＇s Republic of China Social Insurance Law （draft） has undergone three readings at the Standing Committee of the National People＇s Congress. The Law, once promulgated, will be of great significance to implementation of the constitutional principle of ＂respecting and protecting human rights.＂ It will help regulate the various social insurance relationships and the rights and obligations of the parties involved.展开更多
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
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
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
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
基金Supported by Ministry of Industry and Information(No.K24097)
文摘The value of form factor k at different drafts is important in predicting full-scale total resistance and speed for different types of ships. In the ITTC community, most organizations predict form factor k using a low-speed model test. However, this method is problematic for ships with bulbous bows and transom. In this article, a Computational Fluid Dynamics(CFD)-based method is introduced to obtain k for different type of ships at different drafts, and a comparison is made between the CFD method and the model test. The results show that the CFD method produces reasonable k values. A grid generating method and turbulence model are briefly discussed in the context of obtaining a consistent k using CFD.
文摘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%.
基金the National Natural Science Foundation of China，the Fundamental Research Funds for the Central Universities，the Specialized Research Fund for the Doctoral Program of Higher Education
文摘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.
基金supported by SPUR Studentship from Queen's University Belfastsupported by the National Natural Science Foundation of China (Grant No. 51006019)Petro China Innovation Foundation from China National Petroleum Corporation (Grant No. 2010D-5006-0208)
文摘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.
基金supported in part by the National Natural Science Foundation of China (No. 61751210)the Jiangsu Natural Science Foundation of China (No. BK20171417)the Fundamental Research Funds for the Central Universities(No. NG2019002)
文摘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.
文摘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.
文摘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.
文摘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
文摘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.
文摘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.
文摘The People＇s Republic of China Social Insurance Law （draft） has undergone three readings at the Standing Committee of the National People＇s Congress. The Law, once promulgated, will be of great significance to implementation of the constitutional principle of ＂respecting and protecting human rights.＂ It will help regulate the various social insurance relationships and the rights and obligations of the parties involved.
文摘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
文摘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-
文摘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
文摘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
