Identification of key factors of ship detention under Port State Control

Incorporation of deficiency data into the analysis of the dependency and interdependency among the risk factors influencing port state control inspection

<abstract><p>Maritime transport plays an important role in global supply chain. To guarantee maritime safety, protect the marine environment, and enhance the living and working conditions of the seafarers, international codes and conventions are developed and implemented. Port state control (PSC) is a critical maritime policy to ensure that ships comply with the related regulations by selecting and inspecting foreign visiting ships visiting a national port. As the major inspection result, ship detention, which is an intervention action taken by the port state, is dependent on both deficiency/deficiencies (i.e., noncompliance) detected and the judgement of the inspector. This study aims to predict ship detention based on the number of deficiencies identified under each deficiency code and explore how each of them influences the detention decision. We innovatively view ship detention as a type of anomaly, which refers to data points that are few and different from the majority, and develop an isolation forest (iForest) model, which is an unsupervised anomaly detection model, for detention prediction. Then, techniques in explainable artificial intelligence are used to present the contribution of each deficiency code on detention. Numerical experiments using inspection records at the Hong Kong port are conducted to validate model performance and generate policy insights.</p></abstract>

Ship detention decision plays a key role in port state control (PSC) inspection process, which is compactly related to navigation safety and maritime environmental protection. Many focuses were paid to exploit intrinsic relationship among ship attributes (ship age, type, etc.), detention events and typical ship deficiencies. It is noted that many ship detention prediction frameworks were implemented considering single type of factors regardless of internal relationship between ship crucial deficiencies and ship attributes. To address the issue, we proposed a support vector machine (SVM) based framework to exploit crucial ship deficiencies, and thus forecast the probability of ship detention event. Firstly, we design a feature selection scheme to determine ship fatal deficiency types by exploring historical PSC inspection data. Secondly, we predict the ship detention event via conventional support vector machine (SVM) with support of ship feature selection outputs. Thirdly, we verify the proposed framework performance by predicting ship detention event from historical PSC data, which is quantified with the indicators of accuracy () and area under ROC curve (). The research findings help PSC officials easily identify fatal ship deficiencies, and thus make more reasonable ship detention decision in real-world PSC activity.

The Paris Memorandum of Understanding on Port State Control (MOU) shall eliminate the operation of substandard ships in the ports of Europe. It does not set up additional safety requirements. Instead, it shall help to enforce rules and standards laid down in international agreements ("relevant instruments") on ships regardless of the flag they are flying. The control is carried out by surveyors (Port State Control Officers, PSCOs) appointed by the port state authorities. Ships are selected for control with regard to the typical hazards that certain types of ships pose, and to a "rolling list" of flags with especially high detention rates. If a deficiency is found, the surveyor can impose measures ranging from an instruction to rectify them before departure, or within two weeks, or in the next port of call, to the detention of the ship. The legal basis for the detention must be found in the "relevant instruments" implemented by the domestic law of the port state. The owner or operator of the detained ship has a right of appeal. Appeal, however, does not suspend detention.

Port State control (PSC) is an important method which the Port State adopts to manage ship safety and marine pollution in its territory. During the process of promoting the construction of the 21st Century Maritime Silk Road (MSR), subject to economic development and shipping, there is a lack of unified standards and requirements among different states along MSR, which causes many problems. Firstly, the level of economic development among countries around MSR is different leading to some countries cannot afford to develop their PSC. There is a lack of cooperation among these countries. Secondly, the PSC levels of most countries along MSR are weak. Moreover, the standards of PSC and the capacity of the officers of the Port State are different. Lastly, there is a deviation in the direction of the same State’s PSC. They are even not clear on the major functions of PSC, so they may be confused by the pre-supervision and the latter examination. Therefore, taking advantage of the experience from the successful PSC organizations, the states may learn from the examples of the new mechanism under Paris MOU and Tokyo MOU, then formulate the cooperative mechanism fitting better to them. In order to fulfill this goal, the authors shall try to unify the standards of PSC, quantify the PSC content index, and rectify the direction of PSC among different states along MSR. In the meantime, the states shall strengthen information exchanges and further develop extensive cooperation, and improve the modes of cooperation about shipyard and ship classification society among countries. Then it will create a favorable environment for the development of shipping and the MSR construction.

Ship detention serves as an obligatory but efficient manner in port state control (PSC) inspection, and accurate ship detention prediction provides early warning information for maritime traffic participants. Previous studies mainly focused on exploiting the relationship between ship factors (i.e., ship age and ship type) and PSC inspection reports. Less attention was paid to identify and predict the correlation between ship fatal deficiency and ship detention event. To address the issue, we propose a novel framework to identify crucial ship deficiency types with an optimized analytic hierarchy process (AHP) model. Then, the Naïve Bayes model is introduced to predict the ship detention probability considering weights of the identified crucial ship deficiency types. Finally, we evaluate our proposed model performance on the empirical PSC inspection dataset. The research findings can help PSC officials easily determine main ship deficiencies, and thus, less time cost is required for implementing the PSC inspection procedure. In that manner, the PSC officials can quickly make ship detention decision and thus enhance maritime traffic safety.

Ship inspection strategies: Effects on maritime safety and environmental protection

Identifying crucial deficiency categories influencing ship detention: A method of combining cloud model and prospect theory

Port State Control (PSC) is a critical inspection mechanism used to regulate and remove substandard foreign ships in national ports, with the aim of ensuring compliance with safety and pollution regulations to prevent threats to the environment. With the heavy and concentrated traffic volumes at ports, executing efficient and effective PSC inspections has become increasingly challenging. This study investigates the risk factors of ship detention and identifies the most critical factor for detention to strengthen maritime safety and environmental protection towards cleaner environment. Using six years dataset with a total inspection of 178,153 from 2010 to 2015, a Bayesian network model was developed to analyze the influencing factors of inspection that lead to detention viz. The flag State, ship type, recognized organization, inspection authority and ship age. The results indicate that the flag State has the greatest influence, followed by ship type, recognized organization, inspection authority and ship age in descending order of importance. These findings guide PSC officers and ship owners in identifying critical areas to enhance maritime safety, promote environmental sustainability and achieve a cleaner environment. A similar approach can be applied to PSC inspection records from other years for further analysis.

Remote inspection refers to an inspection where the inspector is off-site, whilst the intermediary (inspected entity, vessel’s crew or shore office personnel) is operating on-site. The process is performed via the use of technological, visual or database/portal means. The notion of remote inspections is not new in the maritime industry. The quest to apply efficient and cost-effective inspection techniques on commercial vessels has been underway for years and was closely correlated with the advancement of technology. Nevertheless, until the outbreak of the pandemic, such practices were subject to certain limitations: reliable technology and accepted procedural frameworks should be in place. These could only be applied against certain regulatory backgrounds and performed by qualified inspectors. However, during the prolonged Covid-19 pandemic crisis, unprecedented conditions emerged which significantly affected the ship inspection procedures and in particular the controls by the Port State Authorities and the inspections from energy companies, members of the Oil Companies International Marine Forum (OCIMF) Ship Inspection Report Programme (SIRE). These unforeseen conditions mandated an acceleration of pace towards the adoption of remote inspection schemes. During the pandemic, most Port States had to refrain from physically attending vessels to conduct Port State Control (PSC) inspections. Alternative means of inspections had to be employed by PSC Authorities with the aim of maintaining an acceptable level of control over substandard ships calling at their ports. Proceeding one step further, Tokyo Memorandum of Understanding (MoU) has officially and permanently established a remote inspection system introducing technical specifications for remote inspections that may be conducted only with the consent of the Master. Further to the remote inspection techniques adopted by the US Coast Guard (USCG), Tokyo MoU has introduced live streaming interviews with the Master, officers and crew members. Livestreaming inspections, where the PSC officer may request the crew to visit specific areas of the vessel and witness live tests and operational controls, were established. It is anticipated that the feedback collected from the implementation of the first official remote PSC inspection regime will be exploited also by other PSC MoUs which will proceed with similar schemes in the near future. Embarking in the same direction, OCIMF, following an official announcement in August 2020, launched the remote inspection as an alternative against the restrictions imposed by the pandemic towards the physical SIRE inspections (OCIMF in Temporary guidelines for conducting a vessel inspection during Covid-19, 2020a; OCIMF in Guidelines for remote Inspections under OCIMF programmes (2nd ed.), 2020b). The option to conduct a remote SIRE inspection lies at the discretion of submitting companies, considering several factors including but not limited to the practical possibility and risks of conducting physical attendance at specific ports. The remote SIRE inspections scheme set certain standards for the development of the next Vessel’s Inspection Programme by OCIMF (SIRE 2.0) but at the same time generated concerns regarding the equal assessment of remote reports by individual OCIMF members.

1. The Regime and Access to Foreign Ports - a Definitional Controversy. 2. International Legal Standards and Regulation of Vessel Source Pollution. 3. The Nationality of Ships and the United Nations Convention on Conditions for Registration of Ships. 4. Open Registries and Substandard Vessels - the Role of International Organizations. 5. Port State Enforcement Regime. 6. The Paris Memorandum of Understanding - a Regional Enforcement Regime. Appendices: I: Formulation of Port State Provisions during the Negotiations for the Adoption of the UNCLOS. II: Documents on Enforcement Measures. III: Procedures for the Control of Ships and Discharges. IV: Paris Memorandum of Understanding on Port State Jurisdiction. V: Ministerial Declaration of the Fourth Ministerial Conference on Port State Control: Safe Operation of Ships and Pollution Prevention.

Game model for a new inspection regime of port state control under different reward and punishment conditions

Port state control (PSC) inspection is an important measure to improve ship safety and reduce ship accident rate. To improve the effectiveness of PSC inspections, some MoUs have begun to implement new inspection regime (NIR). However, the effectiveness of NIR remains to be studied. Then this study aims to verify the effectiveness of NIR and improve shipping safety. In this study, Bayesian Network model is used to establish the relationship between NIR, ship deficiencies, detention and ship accident to explore the impact of NIR on maritime safety. The data in this study are from PSC inspection data in the Tokyo Memorandum of Understanding (MoU) and accident data in the International Maritime Organization (IMO). By analyzing the changes of the number of ship deficiency, detention rate and accident rate before and after NIR implementation, the effectiveness of NIR can be verified. The results show that the implementation of NIR does not effectively reduce the number of substandard ships, but the number of ships with serious deficiencies is significantly reduced. However, ship accident rate has not declined. Therefore, it is believed that Tokyo MoU needs to further improve the effectiveness of NIR and strengthen supervision of defective ships.

Comprehensive analysis of ship detention probabilities using binary logistic regression method with machine learning

This article is based on 183 819 port state control inspections from various port state control regimes for the time frame 1999 to 2004. Using binary logistic regression, we establish the differences of port state control inspections across several regimes, even though theory predicts there should be no significant differences in treatments of vessels. The results indicate that the differences towards the probability of detention are merely reflected by the differences in port states and the treatment of deficiencies and not necessarily by age, size, flag, class or owner as perceived by the industry and regulators. The analysis further shows that some differences can be found across ship types and regimes and that there appears to be room for further harmonization in the area of port state control.