Marine Traffic System Research Articles

A IMPORTÂNCIA DO SERVIÇO DE TRÁFEGO DE EMBARCAÇÕES PARA NAVEGAÇÃO EM ÁGUAS INTERIORES

A marine traffic control system (VTS) is defined as the service provided by the officer responsible for marine traffic in a given area. Typical services are based around helping ships enter and pass through a traffic area such as a port or canal. These areas are defined as high risk and therefore, without the said officer, they have a high probability of accidents. Thus, the service consists of identifying the different points of risk, be it the distance between two ships, the speed, the angle of entry, etc. to assign levels of danger and a protocol on how to react in each circumstance. Identifying hazards in time is your goal. This study aims to describe the importance of the VTS for navigation in inland waters, which is done through a qualitative bibliographical research. In the end, it was concluded that for maritime navigation in inland waters to be carried out safely, it is necessary to use the VTS, and in Brazil Porto Açu was the first to have the system and currently, others are in the process of being implemented.

Electromagnetic Metasurface with Object Information and Position Illusion in Radar Vision at Microwave Frequencies

AbstractCamouflage skills are important for understanding the relationship between predators and prey in ecological systems. Mimicry is a common strategy used by creatures to alter their appearance in order to blend in with their surroundings and avoid detection. This paper unveils a previously unknown camouflage strategy that creates false object information and positions of an object in the visual range of radar sensor vision. A dispersion‐modulated illusionary metasurface to realize focal spot coding in a 3‐dimensional space to fit the radar imaging process is proposed. As the radar image indicates, an aircraft image is created by a flat metasurface plane with good polarization adaptation ability. Design, simulation, and experimental results validate the study. This camouflage strategy indicates the complexity of the food chain and can be used by both predators and prey, providing accessible insights for maintaining biological diversity. The metasurface‐based system can be potentially utilized in future radar markers for marine traffic control systems.

Research on Navigation Safety Evaluation of Coastal Waters Based on Dynamic Irregular Grid

Despite being a minor probability event, marine accidents can cause serious consequences such as casualties, environmental damage, and even massive economic losses. As an important part of the marine traffic safety system, the evaluation of navigation safety in coastal waters is of great significance to ensure the safety of ship navigation. In order to objectively evaluate the safety of navigation, this paper proposes an irregular grid division method that combines influencing factors including seabed topography, ship traffic flow, electronic charts, and marine meteorology. In this work, the navigable boundary was extracted by spatial analysis algorithms of the slope calculation. Based on the alpha-shape algorithm and the Voronoi diagram, the constrained Delaunay triangulation was used to extract the inner and outer boundaries of the ship′s navigation area, and the time-varying factors of marine hydrology and meteorology were integrated to form a dynamic irregular grid. The navigation safety evaluation indicators in coastal waters were divided into five risk levels, namely lower, low, medium, high, and higher. Then, the entropy weight theory was used to calculate the weight of the evaluation index. Finally, a safety evaluation model was constructed to evaluate the risk of navigation safety in coastal waters. Herein, taking the coastal waters of Lianyungang Port as a demonstration area, this paper divided the dynamic irregular grid and conducted the navigation safety analysis and evaluation based on the grid. The experimental results show that our method fully considers the influence of objective factors and the uncertainty of safety evaluation indicators and has favorable adaptability to the evaluation of navigation safety in coastal waters.

Empirical analysis of complex network for marine traffic situation

With the increasing activities in waters, the maritime management departments have a strong demand on improving traffic service to enhance the safety of water transportation. Therefore, the quantitative expression of Marine Traffic Situation (MTS) has attracted numerous attention from numerous scholars. At present, there is no macro index to indicate the complexity of MTS. This work proposed the marine traffic complexity inspired by the theories of complex network and network dynamics. The ship was regarded as the vertex, the relationship between the ships is seen as the edge, and then the Marine Traffic Situation Complex Network (MTSCN) was established. Moreover, the topological characteristics such as degree, vertex strength, clustering coefficient and network structure entropy were used to statistically characterize the evolution of marine traffic system. The scenario analysis based on real traffic data was introduced to reveal the variation of MTS, where the scale-free characteristics and inhomogeneity of the MTSCN were found. The results show that the complex network can provide an intuitionistic and accessible metric to reflect the essence of marine traffic flow, which plays an important role in understanding the marine traffic system, managing and controlling the marine traffic safety in the future.

Capacity analysis of ship-tugging operations in a large container port

Abstract In this study, we deal with the simulation problem of ship-tugging operations in a large container port. First, we build a tugboat-service network using a directed graph, where the nodes consist of tugboat bases, anchorages, and berths while the arcs represent the directed links between nodes. Second, we develop a marine traffic simulation system, which can simulate maritime traffic conditions in restricted waters, such as large container ports and busy straits. The marine traffic simulation system is a customized system. Users are allowed to set their study areas and virtual traffic environment (such as traffic demand and network structure) at will. Finally, we conduct various simulations for a real tugboat-service network of Singapore Port, which includes one anchorage, one tugboat base, two berths, and two channels between the anchorage and berths. A detailed analysis of the tugging capacity is provided based on simulation results.

Path Analysis of Causal Factors Influencing Marine Traffic Accident via Structural Equation Numerical Modeling

Many causal factors to marine traffic accidents (MTAs) influence each other and have associated effects. It is necessary to quantify the correlation path mode of these factors to improve accident prevention measures and their effects. In the application of human factors to accident mechanisms, the complex structural chains on causes to MTA systems were analyzed by combining the human failure analysis and classification system (HFACS) with theoretical structural equation modeling (SEM). First, the accident causation model was established as a human error analysis classification in sight of a MTA, and the constituent elements of the causes of the accident were conducted. Second, a hypothetical model of human factors classification was proposed by applying the practice of the structural model. Third, with the data resources from ship accident cases, this hypothetical model was discussed and simulated, and as a result, the relationship path dependency mode between the latent independent variable of the accident was quantitatively analyzed based on the observed dependent variable of human behavior. Application examples show that relationships in the HFACS are verified and in line with the path developing mode, and resource management factors have a pronounced influence and a strong relevance to the causal chain of the accidents. Appropriate algorithms for the theoretical model can be used to numerically understand the safety performance of marine traffic systems under different parameters through mathematical analysis. Hierarchical assumptions in the HFACS model are quantitatively verified.

Radar Technology Trends for Marine Traffic System

Radar Technology Trends for Marine Traffic System

A study of the distribution of marine incidents in the harbours and waters surrounding Taiwan

This research aims to discover information underlying the historical records of marine incidents in order to develop an effective marine traffic management system and rescue resource allocation system in the harbours and waters surrounding Taiwan. Data were collected from the official records of the Taiwanese Ministry of Transportation and Communications and the Coast Guard Administration of Taiwan. Data analysis and Google Earth were utilized to determine the locations of the occurred incidents. The results revealed that on an annual basis, the proportion of marine incidents outside of harbours was much higher than the incidents that took place within harbours. The results also showed that the rate of increase for marine incidents significantly decreased outside of harbours, but increased within harbours, both for commercial vessels and fishing boats from 2005 to 2009. Certain events, such as collisions/contacts, groundings/standings, mechanical malfunctions/failures, and fires/explosions accounted for more than half of the occurred accidents. Finally, the identification of incident locations provides visual evidence to elucidate precisely where the problems are and where rescue resources should be optimally allocated. Recommendations and implications for marine traffic management policy were discussed.

航行環境の現状分析(海上交通の現状分析, 海上交通計画)

航行環境の現状分析(海上交通の現状分析, 海上交通計画)

MTSS -- A Marine Traffic Simulation System and Scenario Studies for a Major Hub Port

Hub ports need to ensure that their navigational networks can fulfill increased demand in marine traffic. They also need to assess the possible impacts of an accident resulting in partial or complete closure of navigation channels. For lack of adequate analytical tools, modeling and simulation are the only means for such studies. To date, however, no adequate simulation tool exists for modeling and simulating the complex traffic at a large-scale hub port. The challenge is to efficiently model the large number of interacting vessels while accurately reflecting the navigational behaviors of various types of vessels whose movements must comply with prevailing protocols in a location- and situation-aware fashion. We present a systematic approach that enables the construction of a marine traffic simulation system called MTSS. MTSS was calibrated based on detailed analysis of historical records obtained from a major hub port, and it was validated by the domain experts. MTSS was used in a capacity study of marine traffic at a hub port that is unique in the scale and complexity of its waterway networks, the intricacies of its traffic patterns, and the required accuracy of the navigational behaviors of different types of vessels. The usefulness of MTSS is further demonstrated by applying it to assess the impacts of partial closure of a waterway under an emergency scenario. For large-scale hub ports, MTSS now opens up new possibilities of realistic scenario studies and disruption management.

VTS 센서를 이용한 3D영상 분석에 기초한 파랑 정보 추출 알고리즘 성능 비교

해양사고가 빈번히 발생함에 따라 해상교통관제를 통해 항해의 안전성과 효율성을 개선하기 위한 해상 트래픽 모니터링 시스템을 구축할 필요성이 대두되고 있다. 이와 같은 목적을 위해, 최근에 X-대역 해양 레이더는 해수면 정보를 수집하는데 사용하고 있는데, 파랑 정보를 정확하게 측정하여 해상교통관제 영역 내에서 선박의 안전하고 효율적인 움직임을 제공하는 것이 요구된다. 본 논문에서는 세 가지의 다른 해류 속도를 산출하는 방법 즉, 최소자승법을 이용한 방법, 해류 속도를 반복 최소자승 갱신 방법, 가변적인 해류 속도의 정규화된 스칼라 곱을 극대화하여 해류 속도 추정치를 제공하는 방법 등에 대해 부이 데이터와 비교하고, 그런 후에 반복 갱신 방법을 수정하여 초기의 해류 속도를 개선하여 효과적으로 파랑 정보를 예측하도록 설계된다. 다수의 실험을 통하여 제안한 방법은 기존 방식에 비해 파랑 정보를 효과적으로 추출할 수 있음을 보인다. As marine accidents happen frequently, it is required to establish a marine traffic monitoring system, which is designed to improve the safety and efficiency of navigation in VTS (Vessel Traffic Service). For this aim, recently, X-band marine radar is used for extracting the sea surface information and, it is necessary to retrieve wave information correctly and provide for the safe and efficient movement of vessel traffic within the VTS area. In this paper, three different current estimation algorithms including the classical least-squares (LS) fitting, a modified iterative least-square fitting routine and a normalized scalar product of variable current velocities are compared with buoy data and then, the iterative least-square method is modified to estimate wave information by improving the initial current velocity. Through several simulations with radar signals, it is shown that the proposed method is effective in retrieving the wave information compared to the conventional methods.

An Empirical Study on the Improvement of Marine Traffic System at the Pyeong-taek Adjacent Areas

This study focused on the investigating of the improving measure of marine traffic system around Pyung-Taek Pilotage area. First, we analyzed the marine traffic environment on the study area based on the expert point of view of pilot and shipmasters. Then suggested the following countermeasures to improve the traffic safety according to the analytic results of the hazardous items on the Jangan-Seo and Ippa pilot embarking/disembarking area. We suggested to establish Mokdeok-do TSS and TSS in Ando area, and to adjust the width of Jangan-seo TSS to improve the congestion on the TSSs. Also suggest to put lightbuoys along the outer limit of the TSS. In addition, recommend to establish traffic safety specific area on the Jangan-seo/Ippa-do water, and to suggest expand the anchorage area of Ippa and Jangan-seo anchorage. It is anticipated to improve the traffic safety on the study area through the marine traffic system improvements.

Procedure for Marine Traffic Simulation with AIS Data

It is essential to evaluate safety of marine traffic for the improvement of efficiency and safety of marine traffic. Spread of AIS makes observation of actual marine traffic more easily and faster than before. Besides, description of collision avoidance behaviours of ships are indispensable to simulate a realistic marine traffic. It is important to develop and implement an algorithm of collision avoidance corresponding to a target traffic or target area into the marine traffic simulation because actual actions for collision avoidance depend on circumstances where ships are sailing. The authors developed an automated marine traffic simulation system with AIS data. And in this paper, the authors proposed a series of systematic procedures for marine traffic simulation including analysing for collision avoidance behaviours using AIS data.

Risk Evaluation in Marine Traffic Systems Based on Fuzzy Catastrophe Theory

The main purpose of MArine Traffic Safety System (MATSS) study, based on catastrophe theory, is to ensure the safety of marine traffic and reveal the essence of traffic risks, and so as to create an effective risk prediction and control mechanism. In this paper, cusp catastrophe was modeled and evolutionary path of MATSS was described. Hence, Fuzzy Catastrophe Theory was concluded. This theory combines Fuzzy Math with Catastrophe Theory and is derived from analysis of uncertainties of marine traffic, including dynamics, irreversibility and mutability. The adverse impacts of system potential function and uncertainties of outside controlling factors were minimized via developing such a theory. The marine traffic risk model was created taking perspectives of various observers into consideration accordingly. As a result, Fuzzy Catastrophe Evaluation Method was presented, which is beneficial to the system safety state evaluation and decision. In the end of the paper, the objectivity and rationality of the method was validated by MATLAB, which has broad application in marine risk prediction and control.

Performance Improvement Based Authentication Protocol for Intervessel Traffic Service Data Exchange Format Protocol Based on U-Navigation System in WoT Environment

International Association of Lighthouse Authorities (IALA) is developing the standard intersystem VTS exchange format (IVEF) protocol for exchange of navigation and vessel information between VTS systems and between VTS and vessels. VTS (vessel traffic system) is an important marine traffic monitoring system which is designed to improve the safety and efficiency of navigation and the protection of the marine environment. And the demand of Inter-VTS networking has been increased for realization of e-Navigation as shore side collaboration for maritime safety. And IVEF (inter-VTS data exchange format) for inter-VTS network has become a hot research topic of VTS system. Currently, the IVEF developed by the International Association of Lighthouse Authorities (IALA) does not include any highly trusted certification technology for the connectors. The output of standardization is distributed as the IALA recommendation V-145, and the protocol is implemented with an open source. The IVEF open source, however, is the code used to check the functions of standard protocols. It is too slow to be used in the field and requires a large memory. And the vessel traffic information requires high security since it is highly protected by the countries. Therefore, this paper suggests the authentication protocol to increase the security of the VTS systems using the main certification server and IVEF.

THE APPLICATION OF METHODS OF ROBUST M-ESTIMATION IN ESTABLISHING SHIP POSITION IN MARINE TRAFFIC SURVEILLANCE SYSTEMS BASED ON RADAR OBSERVATIONS

ABSTRACT In the last years considerable emphasis has been placed on safety at sea. There is the maritime security and surveillance system whose main aim is to execute tasks in the interests of maritime safety and to react in case of emergency. They are monitored by networks of radar stations. On such areas we obtain a lot of navigation data which could be used to improve ship’s parameters (position), using know in geodesy modern M-estimation methods. Simultaneous acquisition of navigational information from many independent radar stations will render it possible to obtain a more accurate ship position in marine traffic surveillance systems in relation to the calculated position. A position expected in an adjustment calculus is received from a watch officer. It is burdened with a fallacy of navigation systems and the quality of marking ship’s route on a map. In the case of navigational-parameter measurements used for depicting ship position, one can obtain incorrect results due to a disturbance in the measurement process. In extreme cases, such erroneous data could significantly differ from the anticipated results. Deviating observations could significantly influence the values of measurement results. In order to eliminate the determination of erroneous measurements, one could use resistant estimation methods with suitably selected attenuation functions. The accuracy of a determined position will not be better than the capabilities of the device used. Adjustment gives the possibility of eliminating or minimizing human errors as well as the errors in the indications of navigational devices. This paper presents the latest robust estimation methods using Danish attenuation function for adjustment of navigational observation, using radar observation.

미포항 비상정박지 지정에 관한 연구

In the port of Ulsan with the area of harbor limit of , 25,432 vessels have been entering annually and only 35 vessels can anchor simultaneously at the anchorage. The area of harbor limit of Ulsan constitutes just 65 percent compared to which is an average of main ports in Korea. In this regard, the port of Ulsan needs to expand the area of anchorages inevitably for enhancing the efficiency of port operation. To select the best anchorage area in Mipo harbor with the introduction of a concept of emergency anchorage, this study analyzed the safety of navigation and anchorage, and safety management, etc. in the prospected anchorage on the basis of the marine traffic survey observing traffic density. Furthermore, after drawing preliminary and final schemes through gathering the opinions from maritime users, safety management organizations and academic experts group, the best arrangement of emergency anchorage has been selected through the conference of interested parties. Then, the final scheme was also verified through figuring out the marine traffic system and carrying out the ship handling simulation.

輸送の三原則を統合した国際海上輸送システム創出の研究-(最終報告)( 輸送の三原則)

輸送の三原則を統合した国際海上輸送システム創出の研究-(最終報告)( 輸送の三原則)

해양교통시설물용 다채널 AFS 설계

Abstract: Recently, there are active research activities regarding to power systems of marine traffic facilities using a hybrid generation system which includes a photovoltaic generation system and a wave power generation system. However, when the marine traffic system is operated on a maritime environmentfor a substantial period of time, it was reported that the shellfish was adhered inside the water column. Totackle this problem, researches on the AFS (Anti-Fouling System) are on the progress. However, use of thesingle channel AFS resulted in frequent replacement of anode. Thus, the paper proposes a multi-channel method on AFS and experiments have been taken place correspondently. To improve the reliability of theexperiment, the melting anode result was applied to our simulation program. The outcome of the simulationillustrates that the proposed multi-channel AFS's anode in the buoy have been ionized equally. Key words: AFS, Multi channel, Single channel, Ionization †교신저자(한국해양대학교 메카트로닉스공학부, E-mail:ojs@hhu.ac.kr, Tel:051-410-4283)1 한국해양대학교 메카트로닉스공학부

우리나라 선박 항로구간의 DGPS 전파 특성에 관한 연구

1999년부터 운영이 시작된 팔미도, 어청도 DGPS 해상 기준국을 시작으로 우리나라에서는 총 17개의 DGNSS 기준국을 운영하고 있는 명실상부한 DGNSS 운영 인프라의 강국이 되었다. 본 논문은 DGPS 해양 기지국을 근간으로 사용하여 우리나라의 대표적인 정기여객선 항로 구간인 제주에서 인천, 부산에서 제주, 제주에서 녹동 구간의 300 ㎑ 주파수의 해상 및 육상에서의 전파특성을 측정하여, 해안 DPGS 기준국에서 서비스 범위를 조사함으로써, 우리나라 DGNSS 서비스 영역을 측정하였다. 서ㆍ남해안의 선박 항로구간의 DGPS 서비스 도달범위를 확인해 본 결과 우수한 품질의 전파신호가 100 NM(권장서비스 범위) 이상 도달됨을 확인하였다. 또한 이를 통하여 선박 안전항행 및 다양한 해양안전시설물에 대하여 위치보정정보의 활용과 향후 DGPS 해양 기준국 확장에 유용할 것으로 판단된다.