• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2019.05a
• /
• pp.206-207
• /
• 2019

우리나라에서 해상교통관제시스템(Vessel Traffic Service, VTS) 구역을 설정하여, 관제사를 중심으로 한 VTS와 선박사이의 해상교통상황 등의 교환을 통해 항만의 안전과 항만운영의 효율을 높이고 있다. 향후, 연안으로 확대될 예정이다. 더 넓은 해역에 대해서는 해양안전종합정보시스템(GICOMS)이 있으며, 선박자동식별장치 (AIS), 장거리위치추적시스템 (LRIT) 등에서 송신하는 선박의 운항정보를 수신하여 전자해도에 표시하고 있다. 이와 같은 선박관제정보는 빅데이터로 향후 자동화된 분석과 제원체계가 요구된다. 여기서는 해상교통관제정보 기초 활용 연구로, 소청초 종합해양과학기지주변의 AIS (Automatic Identification System)정보를 사용하여 선박 활동 특성 해석을 진행하였다.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.20 no.1
• /
• pp.85-94
• /
• 2010

As an automatic identification technology, in which electronic tags are attached to items and system auto-identifies informations of the items using wireless communication technology, use of RFID system is increasing in various fields. According to that, related security problems are becoming important issue. Up to now, many authentication protocols have been proposed to solve security problem of RFID system. In this paper, We show that the RFID authentication protocols in [9, 10], which are compatible with Type C RFID system in ISO 18000-6 Amd1[8], are vulnerable to a spoofing attack. In addition, we propose improved protocols having small additional cost over the original protocols.

• Korean Journal of Remote Sensing
• /
• v.37 no.1
• /
• pp.69-84
• /
• 2021

Awareness of boats is a main issue in areas of fishery management, illegal fishing, and maritime traffic, etc. For the awareness, Automatic Identification System (AIS) and Vessel-Pass System (V-PASS) have been widely used to collect the boat-related information. However, only using these systems makes it difficult to collect the accurate information. Recently, satellite-based data has been increasingly used as a cooperative system. In 2015, U.S. National Oceanic and Atmospheric Administration (NOAA) developed a boat detection algorithm using Visible Infrared Imaging Radiometer Suite (VIIRS) Day & Night Band (DNB) data. Although the detections have been widely utilized in many publications, it is difficult to estimate the night-time fishing boats immediately. Particularly, it is difficult to estimate the threshold due to the lunar irradiation effect. This effect must be corrected to apply a single specific threshold. In this study, the moon phase was considered as the main frequency of this effect. Considering the moon phase, relational expressions are derived and then used as offsets for relative correction. After the correction, it shows a significant reduction in the standard deviation of the threshold compared to the threshold of NOAA. Through the correction, this study can set a constant threshold every day without determination of different thresholds. In conclusion, this study can achieve the detection applying the single specific threshold regardless of the moon phase.

• Korean Journal of Remote Sensing
• /
• v.38 no.1
• /
• pp.45-56
• /
• 2022

The Ieodo Ocean Research Station (IORS) lies between the exclusive economic zone (EEZ) boundaries of Korea, Japan, and China. The geographical positioning of the IORS makes it ideal for monitoring ships in the area. In this study, we introduce ship monitoring results by Automatic Identification System (AIS) and the Broadband 3G^TM radar, which has been developed for use in small ships using the Frequency Modulated Continuous Wave (FMCW) technique. AIS and FMCW radar data were collected at IORS from November 23th to 30th, 2013. The acquired FMCW radar data was converted to 2-D binary image format over pre-processing, including the internal and external noise filtering. The ship positions detected by FMCW radar images were passed into a tracking algorithm. We then compared the detection and tracking results from FMCW radar with AIS information and found that they were relatively well matched. Tracking performance is especially good when ships are across from each other. The results also show good monitoring capability for small fishing ships, even those not equipped with AIS or with a dysfunctional AIS.

• International Journal of Internet, Broadcasting and Communication
• /
• v.15 no.1
• /
• pp.85-96
• /
• 2023

The number of traffic accidents caused by wet or icy road surface conditions is on the rise every year. Car crashes in such bad road conditions can increase fatalities and serious injuries. Historical data (from the year 2016 to the year 2020) on weather-related traffic accidents show that the fatality rates are fairly high in Korea. This requires accurate prediction and identification of hazardous road conditions. In this study, a forecasting model is developed to predict the chances of traffic accidents that can occur on roads affected by weather and road surface conditions. Multiple deep learning algorithms taking into account AlexNet and 2D-CNN are employed. Data on orthophoto images, automatic weather systems, automated synoptic observing systems, and road surfaces are used for training and testing purposes. The orthophotos images are pre-processed before using them as input data for the modeling process. The procedure involves image segmentation techniques as well as the Z-Curve index. Results indicate that there is an acceptable performance of prediction such as 65% for dry, 46% for moist, and 33% for wet road conditions. The overall accuracy of the model is 53%. The findings of the study may contribute to developing comprehensive measures for enhancing road safety.

• International conference on construction engineering and project management
• /
• 2007.03a
• /
• pp.279-288
• /
• 2007

Attempts to achieve a higher productivity have led studies to focus on process improvement. Information has been found as an essential element for process improvement. This research has introduced and focused on two types of information, namely: related jobsite information along the process and feedback information. Related jobsite information along the process which needs to be processed and delivered in a timely manner, accurate, and real time is required to streamline the decision making process. Whereas feedback information about process' current practices which have to be captured and stored is a useful for continuous improvement in identifying the problem origin and determining corrective action. In the current practices, although these two types of information are essential for process improvement, construction process has faced barriers in obtaining that information. Therefore, this research will propose a new information system to overcome the aforementioned barriers. The new information system consists of RFID as an automatic identification and data collection device integrated with database to support construction processes. The new system attempts to provide related jobsite information along the process and feedback information to support decision making process and continuous process improvement respectively. A case study of prefabrication installation process in housing projects has been selected to be implemented in conceptual model of RFID application in construction industry. Conceptual model will be presented in this paper as an initial stage of this ongoing research. Expected outcomes of the new system and future works will be discussed briefly.

• Journal of Korea Trade
• /
• v.27 no.3
• /
• pp.119-146
• /
• 2023

Purpose - As the severity of air pollution caused by the shipping industry is becoming evident, port authorities have started making efforts to reduce air pollutants. Considering the limitations of the currently implemented emission-control area (ECA) and vessel-speed reduction program (VSRP), which are narrow in the designation range and navigation behavior of ships, this study proposes an emission-control route (ECR) that can complement the aforementioned two environmental policies. Design/methodology - This study was conducted on Korea-China trade service routes (ports of call) of regular liners. This study employed vessel-specific data, which is from an automatic identification system (AIS), for 1,728 maritime transportations performed by 387 container vessels during one year (July 1, 2021, to June 30, 2022). Performing a scenario analysis, this study analyzed the effectiveness of reduced air-pollutant emissions. Findings - This study found that the implementation of ECRs could increase average voyage time by 12.38%-25.28% but reduced air-pollutant emissions by 29.02%-43.54%. Additionally, the increase in average voyage times reduces the anchorage time of ships outside ports, providing an incentive for ship operators to voluntarily participate in compliance with regulations, thereby contributing to the establishment of a virtuous cycle of air-environmental policies related to ships. Originality/value - This study aims to verify the policy effectiveness by designing an ECR scope for liner trade routes between Korea and China. Therefore, originality and the value of this study includes conceptualizing the ECR system, analyzing its environmental performance, and exploring new policies that can be implemented while complementing existing policies.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.58 no.2
• /
• pp.175-184
• /
• 2022

This study analyzed the allocation of the skipper's attention during fishing operation in the wheelhouse of a Korean coastal composite fishing vessel by using video observation. To summarize the results, the ratio of lookout, radar and GPS monitoring, which is essential for prevention of collision at sea, was significantly lower than that of other fishing operation due to the attention concentration on the work place during hauling line. In order to reduce exposure to risk of collisions due to concentration of attention to certain tasks such as line hauling, it is necessary to develop an alert system that can notify the approach of other ships or obstruction throughout the ship using information from radar or the automatic identification system. In addition, the order of attention allocation to devices and facilities obtained in this study is expected to be used as basic data for device or facility layout based on the principle of usage frequency in designing wheelhouse for coastal composite fishing vessels in the future.

• Journal of the Society of Naval Architects of Korea
• /
• v.60 no.3
• /
• pp.146-154
• /
• 2023

Efforts have been made to reduce the greenhouse gas emissions from ships by limiting the energy efficiency index, and net zero CO₂ emission was proposed recently. The most ideal measure to achieve zero emission ship is electrification, and fuel cells are considered as a practical power source of the electrified propulsion system. The electric efficiency in the electrochemical reaction of fuel cells can be achieved up to 60% practically. The remaining energy is converted to heat energy but most of them are dissipated by cooling. In the author's previous research, a hybrid propulsion system utilizing not only electricity but also heat was introduced by combining electric motor and steam turbine. In this article, long term efficiency is evaluated for the introduced hybrid propulsion system by considering a virtual 24,000 TEU class container carrier model. To reflect a more practical operating condition, the actual navigation data of a similar real ship in the real world were collected from automatic identification system data and applied. From the result, the overall efficiency of the hybrid propulsion system is expected to be higher than a conventional electric propulsion fuel cell ship by 30%.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2022.11a
• /
• pp.186-186
• /
• 2022

과거에는 선박을 운용하기 위해서 많은 인원이 필요하였으나 최근 들어 선박 운용에 필요한 인원이 줄어들고 있으며, 더 나아가 자율적으로 운항하는 선박을 만들기 위한 연구가 활발히 수행되고 있다. 자율 운항 선박을 구성하는 여러 요소 중 인간의 시각을 대체하기 위한 자율 인지 시스템은 가장 선행되어야 하는 연구 분야 중 하나이다. RADAR (RAdio Detection And Ranging) 및 AIS (Automatic Identification System) 등의 전통적인 인지 센서를 활용한 연구가 진행 중이지만 사각지대나 탐지 주기 등의 한계가 있다. 따라서 본 연구에서는 다중 카메라 (광학, 열상, 파노라마)를 이용하여 전통적인 인지 센서의 한계를 보완하는 새로운 인지 시스템을 고안하였으며, 이를 기반으로 해상 장애물을 추적하여 동적 운동 정보를 얻었다. 먼저 실해역에서 수집한 이미지를 바탕으로 해상 장애물 탐지를 위한 데이터를 구성하고, 딥 러닝 기반의 탐지 모델을 학습시켰다. 탐지 모델을 이용하여 탐지한 결과는 직접 설계한 칼만 필터 기반의 적응형 추적 필터를 통과시켜 해상 장애물의운동 정보 (궤적, 속력, 방향)를 계산하는데 활용되었다. 또한 본 연구는 카메라를 센서로 활용했을 때의 한계를 보완하기 위하여 동 시간대에 다중 카메라에서 추적한 각각의 정보를 융합하였다. 그 결과 단일 카메라를 활용하는 경우, RADAR의 오차 범위 이내에 추적 결과가 수렴하는 양상을 보였으며, 다중 카메라를 활용하는 경우에는 단일 카메라보다 정확한 추적이 가능함을 확인하였다.