Various Types Of Ships Research Articles

Assessment of Dead Ship Condition by the IMO Second Generation Intact Stability Criteria for 5000HP Tug Boat

_ The International Maritime Organization (IMO) has been discussing technical issues by dividing the second-generation intact stability criteria for ships into five types. In this paper, we paid attention to the dead ship condition and introduced the process for the assessment of Levels 1 and 2 in detail. Dead ship condition refers to a case where a large angle of rolling motion occurs due to waves incident on the side of the ship’s hull after the ship’s engine has failed. Basically, in the dead ship condition, if the Level 1 criterion for analysis related to the GZ curve is not satisfied, an evaluation is performed against the Level 2 criterion considering the hydrodynamics of waves. The method for the effective wave slope function required to obtain the spectrum of the effective relative roll angle, which is the most important factor in the calculation of Level 2, was implemented. In particular, unlike existing ship types in terms of various experiences, this study performed stability evaluation using special ship data of a 5000HP tug boat and obtained results that satisfied both Level 1 and 2 standards. Through this example of dead ship condition evaluation for a tug boat, we aim to ensure the expansion of IMO second-generation intact stability evaluation targets for various types of ships. Keywords IMO second generation intact stability criteria; dead ship condition; GZ curve; effective wave slope function; tug boat

Real world emission characteristics of Chinese fleet and the current situation of underestimated ship emissions

Ships are considered important contributors to air pollution and have seriously health impact globally. Although many researchers have carried out studies on emission factors (EFs) in recent years, studies covering various types of ships are rare and the chemical characteristics of particulate matter (PM) emitted by them are unclear. Due to the diversity of different national fleets, the current emission inventory in China established by citing foreign EFs will lead to inaccurate calculation results and generate large uncertainty. In this study, the EFs for ocean-going, harbour, offshore and inland vessels were measured by the portable emission measurement system (PEMS). The specific compositions of PM were analyzed, including carbonaceous components, water-soluble ions (WSI), elements, and polycyclic aromatic hydrocarbons (PAHs). Combined with localized EFs, the ship emission inventory of Qingdao Port was established based on Automatic Identification System (AIS) data. The results show nitrogen oxide (NOx) is the primary pollutant discharged by all ships, followed by sulfur dioxide (SO2). The emissions of SO2 and PM from inland and offshore vessels fueled with high sulfur fuel (HSF) are significantly higher than other ships. Carbonaceous components accounted for 43.4%–53.9% of the total mass of PM, WSI accounted for 9.8%–14.3%, and elements accounted for 16.5%–28.6%. Although the use of low sulfur fuel (LSF) has reduced the emission of V and Ni from ships, it could still be treated as tracer elements of ship emissions. The annual emissions of SO2, NOX, PM2.5, THC and CO from ships in Qingdao port in 2020 were 9728.5, 38503.9, 1424.9, 1331.5 and 2440.4 tons, respectively. The ship emission inventory established based on EPA-recommended EFs resulted in underestimating approximately 16.8% of ship pollutants, especially for SO2 and PM. Ocean-going ships and offshore vessels are major emitters in the study waters. This study is hoped to provide a valuable reference for the further regulation and policy formulation of ship emissions in China.

A transfer learning-based approach to maritime warships re-identification

Marine vessel re-identification technology is an important component of intelligent shipping systems and an important part of the visual perception tasks required for marine surveillance. However, unlike the situation on land, the maritime environment is complex and volatile, and ships are prone to different degrees of swaying. Warships, as a class of ships, are characterized by fewer image samples and high similarity, and it is more difficult to re-identify warships at sea. Therefore, this paper proposes a dynamic alignment re-identification network model incorporating transfer learning methods. Various types of ships are used as source domain data to assist the network in learning the target domain warships so as to improve the recognition accuracy of warships. At the same time, the swaying situation of warships at sea is simulated and tested to improve the recognition difficulty so as to cope with the impact caused by complex sea conditions. The effect of different types of ships as transfer objects is also discussed. The experimental results show that the improved algorithm improves the mean average accuracy (mAP) by 10.2% and the first hit rate (Rank1) by 4.9% on average.

Using Artificial Neural Networks for Predicting Ship Fuel Consumption

Abstract In marine vessel operations, fuel costs are major operating costs which affect the overall profitability of the maritime transport industry. The effective enhancement of using ship fuel will increase ship operation efficiency. Since ship fuel consumption depends on different factors, such as weather, cruising condition, cargo load, and engine condition, it is difficult to assess the fuel consumption pattern for various types of ships. Most traditional statistical methods do not consider these factors when predicting marine vessel fuel consumption. With technological development, different statistical models have been developed for estimating fuel consumption patterns based on ship data. Artificial Neural Networks (ANN) are some of the most effective artificial methods for modelling and validating marine vessel fuel consumption. The application of ANN in maritime transport improves the accuracy of the regression models developed for analysing interactive relationships between various factors. The present review sheds light on consolidating the works carried out in predicting ship fuel consumption using ANN, with an emphasis on topics such as ANN structure, application and prediction algorithms. Future research directions are also proposed and the present review can be a benchmark for mathematical modelling of ship fuel consumption using ANN.

Improvement of the prediction of the added resistance in waves of ships with extreme main dimensional ratios through numerical experiments

After a decade of development, the semi-empirical SNNM (SHOPERA-NTUA-NTU-MARIC) method for the prediction of the added resistance of ships in waves (Liu & Papanikolaou, 2020) was successfully developed and is being widely used by the maritime industry (IMO, 2021; ITTC, 2021). The method is herein updated by use of numerical simulations for the consideration of ships with extreme dimensional ratios, for which experimental data are scarce or non-existent. Numerical experiments are designed to investigate the joint effect of the variation of CB, L/B, and B/T using well-established numerical tools for the added resistance in waves. The patterns observed in the results are then correlated to the parameters through explicit, readily useable mathematical expressions. The improved formula is benchmarked with an experimental database of 11 ships with extreme dimensional ratios of various types. The validation study shows that the improved formula achieved a higher correlation coefficient and a smaller mean percentage error. Thus, the introduced expressions can significantly improve the prediction of the added resistance of various types of ships in waves, including those with extreme dimensional ratios. This study demonstrates how to combine the merits of both numerical and physical experiments to gain insight into complex physical problems.

Strength Analysis of Towing Hook Support Structure on TB. Khatulistiwa 01

Towing hook is one of the important components of a tugboat. Its function is to tow various types of ships, namely containers, tanker ships, and even barges. This activity affects the components to undergo failure and crack, especially the support structure of the hook. Earlier research has analyzed various types of stress characteristics, namely fatigue crack, maximum stress, and maximum factor of safety aimed both at the support structure and the whole profile of the tug. The research aim is to determine the value of stress in the support structure and the safety factor brought by tensile load transferred from the towing hook. The analysis is done using finite element method in Altair Hyper Works 2019. Structural strength of the towing hook support structure is analyzed in 2 loading conditions, namely lightweight barge and full load barge. Two different approaches are used for comparison. The first approach is using barge resistance, and the second is by utilizing maximum tug horse-power to speed ratio. Maximum stress acquired in both loading conditions and both approaches is 118.64 MPa; 121.80 MPa; 230.90 MPa; 329.86 MPa respectively. The safety factor is measured using 2 criteria, BKI permissible stress criterion and BKI Material Strength criterion. Results of safety factors based on BKI permissible stress are 1.644; 1.601; 0.845; and 0.591. According to BKI Material Strength, the safety factors on both loading conditions are 3.371; 3.284; 1.732; and 1.212.

Hazards Identification and Risk Assessment In Welding Confined Space Ship Reparation PT. X With Job Safety Analysis Method

PT X is a docking and shipyard company with experience in repairing various types of ships. Dangers and risks are always exist in every job including ship repair. Therefore, it is necessary to identify hazards and risk assessments. Welding in a confined space includes work that is a source of danger that has the potential to threaten the lives of workers in the ship repair process because access to and exit is limited and is not made to be a continuous work place. The purpose of this study is to identify hazards and assess risks in PT X ship repair confined space welding. The method used in hazard identification and risk control is Job Safety Analysis (JSA) with direct field observations and calculation of likelihood, concequences, and risk values. score on risk assessment according to AS/NZS 4360:2004 and with expert judgment. The results of this study identified that there were 49 potential hazards, then a risk assessment was carried out and there were 36 risks at low risk levels and 13 risks at moderate risk levels. The recommendations given include: using PPE and suction blowers when working, not entering the tank before it is declared safe, taking safety briefings seriously and worker absenteeism, tidying up cables and placing them in a safe position, ensuring workers' hands are dry when in contact with electricity, paying attention to attitude working conditions and conditions around the work area to always be alert

PENERAPAN ISO 45001:2018 MENGGUNAKAN ANALISIS GAP

PT Tri Ratna Diesel Lamongan is a pioneer company in Indonesia that produces various types of ships. Activities of the company can lead to various risks such as accidents and occupational disease, regarding that issue, the company needs to implement occupational health and safety management system that has been known globally. Therefore, PT. Tri Ratna Diesel implements ISO 45001:2018 to create safe and healthy working conditions for all workers. This study aimed to determine the quality of the OHS management system based on ISO 45001:2018 implemented at PT. Tri Ratna Diesel Lamongan.
 This research used a descriptive research method with a cross-sectional approach. Data were collected by interviews and observations. Interviews were conducted with the persons in charge of the OH&S section and the public relations section. The analysis was used to determine the quality of ISO 45001:2018 at PT. Tri Ratna Diesel Lamongan was gap analysis.
 The result of the assessment implementation of ISO 45001:2018 used gap analysis showed that the percentage of assessment in clause 5 about leadership and work participation was 93.75% (good), clause 9 about performance evaluation was 92.30% (good), clause 10 about continuous improvement was 100% (very good). These results indicate that the requirements and procedures of ISO 45001: 2018 have been implemented and well documented. 
 PT. Tri Ratna Diesel Lamongan is advised to conduct a review process of the improvement recommendations that have been given and adjust them to the situation and condition of the company. The review process can be carried out to adjust to each department’s views in PT. Tri Ratna Diesel.

친환경스마트선박의 표준 분류체계에 관한 연구

A wide range of research and development has been undertaken to effectively collect, analyze, and utilize data generated by ships. A data model that enables the exploitation of data generated from ships in various applications is crucial for efficient operation and management. This paper suggests a classification system for data modeling that makes it easy to exploit the data collected from equipment mounted on vessels for ship and land applications. This study compares and analyzes the features of international standards and related domestic systems like SFI, SWBS, JSMEA, and DNVGL-VIS and proposes a classification system that can be commonly used in various types of ships. The applicability of the classification system is discussed for further study, and some data from actual sensors are presented as data IDs according to the classification system proposed.

The Effect of Characteristics and Fatigue of Labor Performance in Shipbuilding Production Room

This shipbuilding company is a pioneer company in Indonesia that produces various types of ships supported by technology from Australia (Computer Design Marine). Risky company activities can work fatigue, so companies need to pay attention to the health and safety of workers. In general, work fatigue is a condition that can occur in workers, where workers experience problems both physically and spiritually after work. Work fatigue is a factor that affects the work where fatigue can directly affect the performance of workers. The purpose of this research is to analyze the effect of characteristics and fatigue on the performance of workers. This study used an analytic research method with a p-type approach cross-sectional. Data was collected using interviews. Sampling is using the Simple Random Sampling method with 64 samples which are conducted to the workers in the shipbuilding production room. To determine the effect between two variables, this research used Chi-Square test analysis. The results showed that age (P=0.038), years of service (P=0.041), and fatigue (P=0.000) affected the performance of workers in the shipbuilding production room, while education level (P=1,000) didn’t affect labor performance in the shipbuilding production room. It is recommended for shipbuilding companies to provide training and rewards (for example by giving compensation) to workers so that they will be more enthusiastic in their work activities and it is necessary to provide light sports coaching activities so that the functioning of body organs is helped them to become stronger and not easily tired.

The implementation of minimum service standards on ship operational performance: Empirical evidence from Indonesia

The purpose of this study was to determine the effect of ship worthiness and seafarers' skills on improving ship operational performance through minimum service standards. Some early indications found in the field, such as the low performance of ship maintenance by procedures, and the obstacles in implementing the ship maintenance plan due to the inefficiency of the ship's operating schedule. This study uses Path Analysis with Path Coefficients Sub Structure 1 and Sub Structure 2. The test method used for the direct effect is the regression method while the indirect effect is the Sobel test. The number of samples is 80 respondents from national shipping companies, from various types of ships, namely, crew boats, patrol boats, utility boats, supply vessels, and anchor handling towing supply. The results of the study indicate that there is a positive and significant effect of seaworthiness and seafarers' skills on increasing ship operational performance, directly or indirectly through minimum service standards. The minimum service standard variable can mediate the indirect effect of the seafarers' skill and ship worthiness variables on the operational performance of the ship. To meet the growing customer satisfaction as the consequences of tight competition, it is necessary to improve the quality of the fleet where durability, cleanliness of the fleet, and safety facilities in the fleet are expected to provide a high guarantee for safety.

Double Feature Extraction Method of Ship-Radiated Noise Signal Based on Slope Entropy and Permutation Entropy

In order to accurately identify various types of ships and develop coastal defenses, a single feature extraction method based on slope entropy (SlEn) and a double feature extraction method based on SlEn combined with permutation entropy (SlEn&PE) are proposed. Firstly, SlEn is used for the feature extraction of ship-radiated noise signal (SNS) compared with permutation entropy (PE), dispersion entropy (DE), fluctuation dispersion entropy (FDE), and reverse dispersion entropy (RDE), so that the effectiveness of SlEn is verified, and SlEn has the highest recognition rate calculated by the k-Nearest Neighbor (KNN) algorithm. Secondly, SlEn is combined with PE, DE, FDE, and RDE, respectively, to extract the feature of SNS for a higher recognition rate, and SlEn&PE has the highest recognition rate after the calculation of the KNN algorithm. Lastly, the recognition rates of SlEn and SlEn&PE are compared, and the recognition rates of SlEn&PE are higher than SlEn by 4.22%. Therefore, the double feature extraction method proposed in this paper is more effective in the application of ship type recognition.

Aerodynamic and Structural Optimisation of Maritime Patrol Radar System Radome using Evolutionary Algorithms

Airborne early warning systems are deployed for collecting surveillance information on airborne enemy targets in real-time. The Maritime Patrol Radar system is used for surveillance of sea surface for various types of ships and low flying aircraft. Radio Detection And Ranging system, or RADAR, in short, is an Electromagnetic sensor integrated on such airborne platforms. An antenna of this radar system is generally mounted under the belly of the aircraft and protected by a cover called a radome. This radome is installed to protect the radar antenna from environmental disturbances. Due to the installation of the radome, increased drag is experienced by aircraft during its flight due to resistance to the flow of the oncoming air. Radome design is a multidisciplinary effort involving structural, aerodynamics, and electromagnetic disciplines. In this study, the multi-disciplinary design of the maritime patrol aircraft radome for optimality in terms of structural strength and aerodynamic performance is carried out by integrating both disciplinary analyses on an optimisation software platform. The utopia point in terms of these two disciplines is found.

Operation Efficiency Analysis of Commercial Hull Insurance Business —— Based on DEA Model

Hull insurance is a kind of Marine insurance, which takes various types of ships as the subject matter of insurance and covers all or part of the losses caused by natural disasters and accidents and the possible liability compensation incurred by them when they are sailing on the sea or berthing in the harbor. A time policy or a voyage policy shall be adopted for Hull insurance. Its characteristic is insurance liability is limited to water only. With the development of economy and the expansion of shipping, China’s Hull insurance industry has developed rapidly. However, no one has studied the operating efficiency of China’s commercial Hull insurance. This paper analyzes the operating efficiency of Hull insurance through DEA analysis method and puts forward relevant suggestions.

Optimized Variational Mode Decomposition and Permutation Entropy with Their Application in Feature Extraction of Ship-Radiated Noise.

The complex and changeable marine environment surrounded by a variety of noise, including sounds of marine animals, industrial noise, traffic noise and the noise formed by molecular movement, not only interferes with the normal life of residents near the port, but also exerts a significant influence on feature extraction of ship-radiated noise (S-RN). In this paper, a novel feature extraction technique for S-RN signals based on optimized variational mode decomposition (OVMD), permutation entropy (PE), and normalized Spearman correlation coefficient (NSCC) is proposed. Firstly, with the mode number determined by reverse weighted permutation entropy (RWPE), OVMD decomposes the target signal into a set of intrinsic mode functions (IMFs). The PE of all the IMFs and SCC between each IMF with the raw signal are then calculated, respectively. Subsequently, feature parameters are extracted through the sum of PE weighted by NSCC for the IMFs. Lastly, the obtained feature vectors are input into the support vector machine multi-class classifier (SVM) to discriminate various types of ships. Experimental results indicate that five kinds of S-RN samples can be accurately identified with a recognition rate of 94% by the proposed scheme, which is higher than other previously published methods. Hence, the proposed method is more advantageous in practical applications.

Empirical analysis on port state control inspection for foreign-registered ships in Malaysian ports

The selection of foreign-registered ships upon entering ports poses challenges to maritime authorities in ensuring the effectiveness of the port state control (PSC) inspection. The derived data from the ships' arrival notification system has been utilised in this study to identify the preferred vessel type for inspection. A combination of the Grey Relational Analysis (GRA) model and Entropy Weight Method (EWM) has been applied to discern the various types of ships that entered five selected ports in Malaysia and disclose the propensity of each vessel type. Based on 100,623 ship arrival records obtained for a period of five years (2015–2019), the types of ships were identified, analysed, scored, and graded. The result shows that the oil tanker has the highest value of grey relational grade for Bintulu port while the passenger ship is in the pole position for Penang port. Kuching port and Port Kelang share the container type as the first in the ranking, whereas Lahad Datu posted the oil tanker. Other results include the sequence of types at individual ports for providing useful information to help policymakers in establishing an effective inspection design. A similar approach is applicable in PSC inspection records for further analysis.

Energy Optimization of the 'Shore to Ship' System-A Universal Power System for Ships at Berth in a Port.

One of the most effective methods of limiting air pollution emissions by ships at a berth in a port is the power connection of ships to the on-shore system. “Shore to Ship” (STS)—A universal system for the connection of the ship’s electrical power network with the on-shore network—ensures the adoption of the voltage and frequency of the on-shore network for the exploitation of various types of ships in the port. The realization of such a system is possible due to the use of semiconductor technologies during the construction of mechatronic systems (i.e., systems that ensure the maintenance of electricity parameters). The STS system ensures energy efficiency for high-power ship systems through the use of an active semiconductor converter. This article presents an analysis of steady state electromagnetic and energy processes, allowing the determination of the active and reactive power and losses in the STS system. The presented analytical research enables the development of a control algorithm that optimizes the system energy efficiency. In the article, the control methods allowing the optimization of the energy characteristics of the system are considered and investigated. On the basis of theoretical studies, a model was developed in the Matlab-Simulink environment, which allowed us to study steady and transient processes in the STS system in order to reduce losses in power lines and semiconductor converters.

Aerodynamic Optimization of Airborne Radome for Maritime Patrol Radar

Airborne Early Warning (AEW) systems are deployed for getting surveillance information on airborne enemy targets. Electromagnetic sensors such as Radars are integrated on airborne platforms for collecting such information. Maritime Patrol Radar (MPR) is used for surveillance of sea surface for various types of ships and low flying aircraft. The antenna of MPR is belly mounted on typical turbo prop aircraft and protected from environment with a cover called Radome. Airborne radomes are electromagnetically transparent. The radome installation introduces additional drag which will reduce the range of the aircraft. To minimise the drag due to installation of radome, the profile has to be stream-lined or optimised with CFD analysis for certain operational points of aircraft flight. Design of radome is multidisciplinary effort involving Aerodynamics, Structures and Electromagnetic disciplines. In this study, aerodynamic optimization of a radome for a given antenna size is carried out using a combination Genetic Algorithm (GA) and traditional optimisation methods to find the Utopia point for further investigation on Multidisciplinary Design Optimization (MDO) of radome. This is necessary to progress on optimisation with other disciplines like Structures and Electromagnetics (EM)

Automatic collision avoidance system with many targets, including maneuvering ones

The article considers the issues of automatic collision avoidance with many targets, including maneuvering ones, which is especially important when navigating a vessel in narrownesses. Was made a brief review of literature devoted to the problem of collision avoidance and conclusion was drown on the relevance of developing such systems. There were developed mathematical and algorithmic support of the combined collision avoidance with many targets, including maneuvering ones. Based on the synthesized algorithms, there was developed software in the MATLAB environment for a simulator of an onboard controller of a ship control system, the operability and efficiency of mathematical, algorithmic and software was tested in a closed circuit with a Navi Trainer 5000 navigation simulator for various types of ships, navigation areas and weather conditions. The experiments confirmed the efficiency of the proposed method and algorithms and allow to recommend them for practical use in the development of modules for automatic collision avoidance with many targets, including maneuvering ones, an onboard controller of the ship’s control system.

AUTOMATIC COLLISION AVOIDANCE WITH MULTIPLE TARGETS, INCLUDING MANEUVERING ONES

Context. There is considered the task of automatic collision avoidance with multiple targets, including maneuvering ones. Theobject of the research is the process of automatic collision avoidance with multiple targets, including maneuvering ones. The subject of research is the method and algorithms that implement the process of automatic collision avoidance from multiple targets, including maneuvering ones.Objective. The purpose of the article is development a method and algorithms for automatic collision avoidance from multipletargets, including maneuvering ones, for the module of the onboard controller of the ship control system.Method. This goal is achieved by periodically measuring the true speed of the vessel and relative speeds of the vessel andtargets, averaging the measured information to remove noise, estimating the true speeds of the targets, building, for the obtained estimates of the true speeds of the targets, areas of allowable collision avoidance controls with each targets by numerical iteration of the collision avoidance parameters (speed and course) at the nodes of a given grid in the area of their possible changes, determining the relative speeds at the nodes of the grid ship and target movement and checking that the relative speeds don’t belong to sectors of dangerous courses, building a general area of acceptable collision avoidance controls with all targets by combining areas of allowable collision avoidance controls with each target, choosing collision avoidance parameters from the general area of acceptable collision avoidance controls according to specified criteria. This allows to diverge from multiple targets, including maneuvering ones, in a fully automatic mode. Changing the criteria for selecting discrepancy parameters leads to a change in the ship’s behavior in case of discrepancy without changing the program code.Results. The developed method and algorithms are implemented in software and investigated by solving the problem of collisionavoidance from multiple targets, including maneuvering ones, in a fully automatic mode in a closed circuit with the simulator NaviTrainer 5000 for various types of ships, targets, navigation areas and weather conditions.Conclusions. The experiments confirmed the performance of the proposed method and algorithms and allow to recommend themfor practical use in the development of modules for automatic collision avoidance with multiple targets, including maneuvering ones, of the onboard controller of the ship control system.