Polish Maritime Research最新文献

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Re-Identifying Naval Vessels Using Novel Convolutional Dynamic Alignment Networks Algorithm 利用新型卷积动态对齐网络算法重新识别海军舰艇
IF 2 3区 工程技术
Polish Maritime Research Pub Date : 2024-03-01 DOI: 10.2478/pomr-2024-0007
Sudipta Roy, D. Jana, Nguyen Long
{"title":"Re-Identifying Naval Vessels Using Novel Convolutional Dynamic Alignment Networks Algorithm","authors":"Sudipta Roy, D. Jana, Nguyen Long","doi":"10.2478/pomr-2024-0007","DOIUrl":"https://doi.org/10.2478/pomr-2024-0007","url":null,"abstract":"\u0000 Technological innovation for re-identifying maritime vessels plays a crucial role in both smart shipping technologies and the pictorial observation tasks necessary for marine recon- naissance. Vessels are vulnerable to varying gradations of engaging in the marine environment, which is complicated and dynamic compared to the conditions on land. Fewer picture samples along with considerable similarity are characteristics of warships as a class of ship, making it more challenging to recover the identities of warships at sea. Consequently, a convolutional dynamic alignment network (CoDA-Net) re-identification framework is proposed in this research. To help the network understand the warships within the desired domain and increase its ability to identify warships, a variety of ships are employed as origin information. Simulating and testing the winning of war vessels at sea helps to increase the network’s ability to recognize complexity so that users can better handle the effects of challenging maritime environments. The impact of various types of ships as transfer items is also highlighted. The research results demonstrate that the enhanced algorithm increases the overall first hit rate (Rank1) by approximately 5.9%; it also increases the mean average accuracy (mAP) by approximately 10.7% and the correlation coefficient by 0.997%.","PeriodicalId":49681,"journal":{"name":"Polish Maritime Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140404589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Hydrodynamic Loads on a Semi-Submersible Platform Supporting a Wind Turbine Under a Mooring System With Buoys 带浮标系泊系统下支撑风力涡轮机的半潜式平台的水动力载荷
IF 2 3区 工程技术
Polish Maritime Research Pub Date : 2024-03-01 DOI: 10.2478/pomr-2024-0003
T. Mazarakos, Theodosis D. Tsaousis
{"title":"Hydrodynamic Loads on a Semi-Submersible Platform Supporting a Wind Turbine Under a Mooring System With Buoys","authors":"T. Mazarakos, Theodosis D. Tsaousis","doi":"10.2478/pomr-2024-0003","DOIUrl":"https://doi.org/10.2478/pomr-2024-0003","url":null,"abstract":"\u0000 In this study, the effect of a 10MW DTU wind turbine (WT) on a semi-submersible platform is examined from the point of view of its dynamic behaviour as part of a mooring system with attached buoys. The platform has a rectangular geometry, and consists of four offset and one main cylindrical members. The structure is assumed to receive both wave and wind loading simultaneously. A coupled analysis within the frequency domain is performed using two boundary element method software packages, NEMOH and HAMS. The results are presented in the form of parametric graphs for each of the software packages used and for varying wave directions. The graphs show the hydrodynamic loads exerted on the platform, the wave elevation, the added masses, the hydrodynamic damping coefficients, the mooring line tensions, and the Response Amplitude Operators (RAOs) for the motion of the platform.","PeriodicalId":49681,"journal":{"name":"Polish Maritime Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140398802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Practical Finite-Time Event-Triggered Control of Underactuated Surface Vessels in Presence of False Data Injection Attacks 在存在虚假数据注入攻击的情况下,对动力不足的水面舰艇进行实用的有限时间事件触发控制
IF 2 3区 工程技术
Polish Maritime Research Pub Date : 2024-03-01 DOI: 10.2478/pomr-2024-0012
Liping Chen, Minghua Sun, Li Wang
{"title":"Practical Finite-Time Event-Triggered Control of Underactuated Surface Vessels in Presence of False Data Injection Attacks","authors":"Liping Chen, Minghua Sun, Li Wang","doi":"10.2478/pomr-2024-0012","DOIUrl":"https://doi.org/10.2478/pomr-2024-0012","url":null,"abstract":"\u0000 The results of studies on a trajectory-tracking problem affected by false data injection attacks (FDIAs) and internal and external uncertainties are presented in this paper. In view of the FDIAs experienced by the system, we compensate for the serious navigation deviation caused by malicious attacks by designing an online approximator. Next, we study the internal and external uncertainties introduced by environmental factors, system parameter fluctuations, or sensor errors, and we design adaptive laws for these uncertainties to approximate their upper bounds. To further enhance the response velocity and stability of the system, we introduce finite-time technology to ensure that the unmanned underactuated surface vessels (USVs) reach the predetermined trajectory-tracking target within finite time. To further reduce the update frequency of the controller, we introduced event-triggered control (ETC) technology. This saves the system’s communication resources and optimizes the system. Through Lyapunov stability theory, a strict and complete stability analysis is provided for the control scheme. Finally, the effectiveness of the control scheme is verified using two sets of simulations.","PeriodicalId":49681,"journal":{"name":"Polish Maritime Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140402107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Study of the Hydrodynamic Characteristics of Anti-Heave Devices of Wind Turbine Platforms at Different Water Depths 不同水深条件下风力涡轮机平台防风浪装置的水动力特性研究
IF 2 3区 工程技术
Polish Maritime Research Pub Date : 2024-03-01 DOI: 10.2478/pomr-2024-0004
Hongyuan Xu, Wei Wang, Yonghe Xie
{"title":"Study of the Hydrodynamic Characteristics of Anti-Heave Devices of Wind Turbine Platforms at Different Water Depths","authors":"Hongyuan Xu, Wei Wang, Yonghe Xie","doi":"10.2478/pomr-2024-0004","DOIUrl":"https://doi.org/10.2478/pomr-2024-0004","url":null,"abstract":"\u0000 This paper focuses on the effect of water depth on the hydrodynamics of floating offshore wind turbines with open-hole anti-heave devices. The three-floating-body wind turbine platform is used as the primary research object in this paper. The effect of water depth on the reduction of the heave motion of a floating platform with anti-heave devices is systematically investigated through a series of experiments and numerical simulations. The results show high agreement between the test results and simulations, with larger values of heave motion in deep water. A wind turbine platform with anti-heave devices can effectively reduce the lifting and sinking motions when the wave period is large.","PeriodicalId":49681,"journal":{"name":"Polish Maritime Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140403537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
An Experimental Study of the Effects of Cylinder Lubricating Oils on the Vibration Characteristics of a Two-Stroke Low-Speed Marine Diesel Engine 气缸润滑油对二冲程低速船用柴油机振动特性影响的实验研究
IF 2 3区 工程技术
Polish Maritime Research Pub Date : 2023-12-01 DOI: 10.2478/pomr-2023-0062
Gang Wu, Guodong Jiang, Changsheng Chen, Guohe Jiang, Xigang Pu, Bi-we Chen
{"title":"An Experimental Study of the Effects of Cylinder Lubricating Oils on the Vibration Characteristics of a Two-Stroke Low-Speed Marine Diesel Engine","authors":"Gang Wu, Guodong Jiang, Changsheng Chen, Guohe Jiang, Xigang Pu, Bi-we Chen","doi":"10.2478/pomr-2023-0062","DOIUrl":"https://doi.org/10.2478/pomr-2023-0062","url":null,"abstract":"Abstract Two-stroke, low-speed diesel engines are widely used in large ships due to their good performance and fuel economy. However, there have been few studies of the effects of lubricating oils on the vibration of two-stroke, low-speed diesel engines. In this work, the effects of three different lubricating oils on the vibration characteristics of a low-speed engine are investigated, using the frequency domain, time-frequency domain, fast Fourier transform (FFT) and short-time Fourier transform (STFT) methods. The results show that non-invasive condition monitoring of the wear to a cylinder liner in a low-speed marine engine can be successfully achieved based on vibration signals. Both the FFT and STFT methods are capable of capturing information about combustion in the cylinder online in real time, and the STFT method also provides the ability to visualise the results with more comprehensive information. From the online condition monitoring of vibration signals, cylinder lubricants with medium viscosity and medium alkali content are found to have the best wear protection properties. This result is consistent with those of an elemental analysis of cylinder lubrication properties and an analysis of the data measured from a piston lifted from the cylinder after 300 h of engine operation.","PeriodicalId":49681,"journal":{"name":"Polish Maritime Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139019356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Human Resource Management Digitalisation in Multidisciplinary Ship Design Companies 多学科船舶设计公司的人力资源管理数字化
IF 2 3区 工程技术
Polish Maritime Research Pub Date : 2023-12-01 DOI: 10.2478/pomr-2023-0065
Piotr Bilon, Wojciech Litwin
{"title":"Human Resource Management Digitalisation in Multidisciplinary Ship Design Companies","authors":"Piotr Bilon, Wojciech Litwin","doi":"10.2478/pomr-2023-0065","DOIUrl":"https://doi.org/10.2478/pomr-2023-0065","url":null,"abstract":"Abstract The digitalisation in the ship design sector is currently applied to the design process itself and is well defined, partially standardised and practically implemented by both independent design companies and the design departments of shipyards. The situation is similar in other sectors of engineering. However, the requirements for the digitalisation of other processes in design and engineering companies have not previously been studied, and the limited financial resources of ship design companies mean that there is a need for research on the digitalisation needs of multidisciplinary ship design companies. The implementation of building information modelling (BIM) solutions is costly for design companies and generates benefits mainly for shipyards and shipowners. The lack of benefits for design companies leads to the hesitation of managers whenever digitalisation is considered; the scope and scale of the digitalisation, as well as the selected software and BIM level, are defined by the shipyard requirements. The participation and support of management in the digitalisation process is one of the key success factors; the expected benefits caused by digitalisation for the organisation will increase the motivation of managers to invest limited resources in digitalisation. There are no data that indicate the processes with a high potential for digitalisation and the scale of expected improvements in ship design companies; therefore, research in this area was performed with a group of project managers from design and engineering companies. The research focused on collecting the opinions and experiences of the managers related to the manual management of resources and comparing the poll results with the conclusions from the enterprise resource planning (ERP) system data analyses. The paper analyses if the digital automation of the resource management process can lead to the substantial improvement of the operations of multi-project, multidisciplinary engineering ship design companies.","PeriodicalId":49681,"journal":{"name":"Polish Maritime Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139015808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Effects of Sway and Roll Excitations on Sloshing Loads in a KC-1 Membrane LNG Tank 摇摆和滚动激振对 KC-1 膜液化天然气储罐中的荡载的影响
IF 2 3区 工程技术
Polish Maritime Research Pub Date : 2023-12-01 DOI: 10.2478/pomr-2023-0057
Se-yeol An, Hyeon-won Jeong, Ohyoung Kim, W. Jaewoo Shim
{"title":"Effects of Sway and Roll Excitations on Sloshing Loads in a KC-1 Membrane LNG Tank","authors":"Se-yeol An, Hyeon-won Jeong, Ohyoung Kim, W. Jaewoo Shim","doi":"10.2478/pomr-2023-0057","DOIUrl":"https://doi.org/10.2478/pomr-2023-0057","url":null,"abstract":"Abstract This study investigates the effects of sway and roll excitations on sloshing liquid loads in a tank, using Ansys Fluent software. The model considered in the study is a 1:50 scaled membrane-type tank, based on a KC-1 membrane LNG tank designed by Korea Gas Corporation (KOGAS). The volume of fluid (VOF) method is used to track the free surface inside the tank, and the standard k-ε model is applied to express the turbulent flow of the liquid. To explore the motion of the tank under excitation, a user-defined function (UDF) and a dynamic mesh technique are employed to control the external forces exerted on the tank through its motion. The results, in the form of time series data on the sloshing pressures in the tank under pure sway, roll, and coupled sway-roll, are analysed, with specific ranges for the excitation amplitudes and frequencies. We show that variations in excitation frequency and amplitude significantly influence the sloshing loads. Sloshing loads are found to intensify when the excitation frequency matches the tank’s primary natural frequency, 1.0 ω1′. Furthermore, with coupled sway-roll excitations, the sloshing loads are weakened when the sway and roll are in-phase and are intensified when these are out-of-phase. Fast Fourier transform analysis provides insights into the frequency domain, showing that the dominant frequency is 0.88 Hz and it is approximately equal to the tank’s primary natural frequency, 1.0 ω1′.","PeriodicalId":49681,"journal":{"name":"Polish Maritime Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139016452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Effects of Propeller Fouling on the Hydrodynamic Performance of a Marine Propeller 螺旋桨污垢对船用螺旋桨水动力性能的影响
IF 2 3区 工程技术
Polish Maritime Research Pub Date : 2023-12-01 DOI: 10.2478/pomr-2023-0059
A. Zinati, M. Ketabdari, H. Zeraatgar
{"title":"Effects of Propeller Fouling on the Hydrodynamic Performance of a Marine Propeller","authors":"A. Zinati, M. Ketabdari, H. Zeraatgar","doi":"10.2478/pomr-2023-0059","DOIUrl":"https://doi.org/10.2478/pomr-2023-0059","url":null,"abstract":"Abstract Propeller performance is typically considered under clean conditions, despite the fact that fouling is an inevitable phenomenon for propellers. The main objective of this study is to investigate the effects of roughness due to fouling on the performance of a propeller using a CFD simulation in conjunction with the roughness function model. A simulation of a clean propeller is verified for a five-blade propeller model using existing experimental results. A roughness function model is then suggested based on existing measured roughness data. The simulations are extended for the same propeller under varying severities of roughness. Initially, it is concluded that KT and ηo gradually decrease with increasing fouling roughness, while KQ increases, compared to smooth propeller. For instance, at J=1.2 for medium calcareous fouling, KT is reduced by about 26%, KQ increases by about 7.0%, and ηo decreases by 30.9%. In addition, for the rough propeller, the extra power required is defined as the specific sea margin (SSM) to compensate for the power loss. A slight roughness causes a large decrease in ηo. A propeller painted with foul-release paint and an unpainted propeller are found to require 2.7% SSM and 57.8% SSM over four years of service, respectively. Finally, the use of foul-release paints for propeller painting is strongly advised.","PeriodicalId":49681,"journal":{"name":"Polish Maritime Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139022093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Quantumness in Diagnostics of Marine Internal Combustion Engines and Other Ship Power Plant Machines 船用内燃机和其他船舶动力装置诊断中的量子化问题
IF 2 3区 工程技术
Polish Maritime Research Pub Date : 2023-12-01 DOI: 10.2478/pomr-2023-0064
J. Girtler, Jacek Rudnicki
{"title":"Quantumness in Diagnostics of Marine Internal Combustion Engines and Other Ship Power Plant Machines","authors":"J. Girtler, Jacek Rudnicki","doi":"10.2478/pomr-2023-0064","DOIUrl":"https://doi.org/10.2478/pomr-2023-0064","url":null,"abstract":"Abstract The article provides proof that the diagnostics of marine internal combustion engines and other ship power plant machines should take into account the randomness and unpredictability of certain events, such as wear, damage, the variations of mechanical and thermal loads, etc., which take place during machine operation. In the article, the energy E, like the other forms (methods) that it can be converted into (heat and work), is considered the random variable Et; at time t, this variable has the mean value E¯t {bar E_t} , which is the observed value of the statistic E¯st {bar E_{st}} with an asymptotically normal distribution N(E(Et),σtn) Nleft( {Eleft( {{E_t}} right),{{{sigma _t}} over {sqrt n }}} right) , irrespective of the functional form of the random variable Et. A proof is given that shows that the expected value estimated in the above way, considering the time t of the performance of task Z by a marine internal combustion engine or other ship power plant machine, can be used to determine the machine’s possible action (DM). When compared to the required action (DW) needed for task Z to be performed, this possible action makes it possible to formulate an operating diagnosis concerning whether the engine or machine of concern is able to perform task Z. It is assumed that an energy device of this type is able to perform a given task when the inequality DM≥DW holds. Otherwise, when DM < DW, the device cannot perform the task for which it was adopted in the design and manufacturing phase, which means that it is in the incapability state, although it still can be started and convert energy into the form of heat or work..","PeriodicalId":49681,"journal":{"name":"Polish Maritime Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139025598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Optimal UV Quantity for a Ballast Water Treatment System for Compliance with Imo Standards 符合伊莫标准的压载水处理系统的最佳紫外线用量
IF 2 3区 工程技术
Polish Maritime Research Pub Date : 2023-12-01 DOI: 10.2478/pomr-2023-0056
Nguyen Dinh Thach, P. V. Hung
{"title":"Optimal UV Quantity for a Ballast Water Treatment System for Compliance with Imo Standards","authors":"Nguyen Dinh Thach, P. V. Hung","doi":"10.2478/pomr-2023-0056","DOIUrl":"https://doi.org/10.2478/pomr-2023-0056","url":null,"abstract":"Abstract Ballast water management is an effective measure to ensure that organisms, bacteria and viruses do not migrate with the ballast water to other areas. In 2004, the International Maritime Organization adopted the International Convention on the Control and Management of Ballast Water and Ship Sediments, which regulates issues related to ballast water management. Many technologies have been researched and developed, and of these, the use of UV rays in combination with filter membranes has been shown to have many advantages and to meet the requirements of the Convention. However, the use of UV furnaces in ballast water treatment systems requires a very large capacity, involving the use of many high-power UV lamps. This not only consumes large amounts of electrical energy, but is also expensive. It is therefore necessary to find an optimal algorithm to enable the UV radiation for the UV controller in the ballast water sterilisation process to be controlled in a reasonable and effective manner. This controller helps to prolong the life of the UV lamp, reduce power consumption and ensure effective sterilisation. This paper presents a UV control algorithm and a controller for a UV furnace for a ballast water treatment system installed on a ship. The results of tests on vessels illustrate the effect of the proposed UV controller.","PeriodicalId":49681,"journal":{"name":"Polish Maritime Research","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139015428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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