• Title/Summary/Keyword: Ship Communication

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Development of Robot Platform for Autonomous Underwater Intervention (수중 자율작업용 로봇 플랫폼 개발)

  • Yeu, Taekyeong;Choi, Hyun Taek;Lee, Yoongeon;Chae, Junbo;Lee, Yeongjun;Kim, Seong Soon;Park, Sanghyun;Lee, Tae Hee
    • Journal of Ocean Engineering and Technology
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    • v.33 no.2
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    • pp.168-177
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    • 2019
  • KRISO (Korea Research Institute of Ship & Ocean Engineering) started a project to develop the core algorithms for autonomous intervention using an underwater robot in 2017. This paper introduces the development of the robot platform for the core algorithms, which is an ROV (Remotely Operated Vehicle) type with one 7-function manipulator. Before the detailed design of the robot platform, the 7E-MINI arm of the ECA Group was selected as the manipulator. It is an electrical type, with a weight of 51 kg in air (30 kg in water) and a full reach of 1.4 m. To design a platform with a small size and light weight to fit in a water tank, the medium-size manipulator was placed on the center of platform, and the structural analysis of the body frame was conducted by ABAQUS. The robot had an IMU (Inertial Measurement Unit), a DVL (Doppler Velocity Log), and a depth sensor for measuring the underwater position and attitude. To control the robot motion, eight thrusters were installed, four for vertical and the rest for horizontal motion. The operation system was composed of an on-board control station and operation S/W. The former included devices such as a 300 VDC power supplier, Fiber-Optic (F/O) to Ethernet communication converter, and main control PC. The latter was developed using an ROS (Robot Operation System) based on Linux. The basic performance of the manufactured robot platform was verified through a water tank test, where the robot was manually operated using a joystick, and the robot motion and attitude variation that resulted from the manipulator movement were closely observed.

Performance Analysis of Multi-GNSS Positioning Accuracy with Code Pseudorange of Dual-Frequency Android Smartphone in Maritime Environment (안드로이드 스마트폰의 이중 주파수 GNSS 의사거리 기반 해상 측위정확도 성능 분석)

  • Seo, Kiyeol;Kim, Youngki;Jeon, Tae-Hyeong;Son, Pyo-Woong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.25 no.11
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    • pp.1588-1595
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    • 2021
  • Android-based smartphones receive the global navigation satellite system (GNSS) signals to determine their location and provide the GNSS raw measurement to users. The available GNSS signals on the current Android devices are GPS, GLONASS, Galileo, BeiDou, QZSS. This research has analyzed the performance of multi-GNSS position accuracy based on the pseudorange of the smartphone for maritime users. Smartphones capable of receiving dual-frequency are installed on a ship, and multi-GNSS raw information in maritime environment was measured to present the results of comparing the GNSS pseudorange-based dual-frequency positioning performance for each smarphone. Furthermore, we analyzed whether the results of the positioning performance can meet the HEA requirement of IMO for maritime navigation users. As the results of maritime experiment, it was confirmed that in the case of the smartphones supporting the dual-frequency, the position accuracy within 6 meters (95%) could be obtained, and the HEA position accuracy performance within 10 meters (95%) required by IMO could be achieved.

A study on the creation of mission performance data using search drone images (수색용 드론 이미지를 활용한 임무수행 데이터 생성에 관한 연구)

  • Lee, Sang-Beom;Lim, Jin-Taek
    • Journal of the Institute of Convergence Signal Processing
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    • v.22 no.4
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    • pp.179-184
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    • 2021
  • Along with the development of the fourth industry, the public sector has increasingly paid more attention to search using drones and real-time monitoring, for various goals. The drones are used and researched to complete a variety of searching and monitoring missions, including search for missing persons, security, coastal patrol and monitoring, speed enforcement, highway and urban traffic monitoring, fire and wildfire monitoring, monitoring of illegal fishing in reservoirs and protest rally monitoring. Police stations, fire departments and military authorities, however, concentrate on the hardware part, so there are little research on efficient communication systems for the real-time monitoring of data collected from high-performance resolution and infrared thermal imagining cameras, and analysis programs suitable for special missions. In order to increase the efficiency of drones with the searching mission, this paper, therefore, attempts to propose an image analysis technique to increase the precision of search by producing image data suitable for searching missions, based on images obtained from drones and provide the foundation for improving relevant policies and establishing proper platforms, based on actual field cases and experiments.

Implementation of Acceleration Sensor-based Human activity and Fall Classification Algorithm (가속도 센서기반의 인체활동 및 낙상 분류를 위한 알고리즘 구현)

  • Hyun Park;Jun-Mo Park;Yeon-Chul, Ha
    • Journal of the Institute of Convergence Signal Processing
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    • v.23 no.2
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    • pp.76-83
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    • 2022
  • With the recent development of IT technology, research and interest in various biosignal measuring devices is increasing. As an aging society is in full swing, research on the elderly population using IT-related technologies is continuously developing. This study is about the development of life pattern detection and fall detection algorithm, which is one of the medical service areas for the elderly, who are rapidly developing as they enter a super-aged society. This study consisted of a system using a 3-axis accelerometer and an electrocardiogram sensor, collected data, and then analyzed the data. It was confirmed that behavioral patterns could be classified from the actual research results. In order to evaluate the usefulness of the human activity monitoring system implemented in this study, experiments were performed under various conditions, such as changes in posture and walking speed, and signal magnitude range and signal vector magnitude parameters reflecting the acceleration of gravity of the human body and the degree of human activity. was extracted. And the possibility of discrimination according to the condition of the subject was examined by these parameter values.

A Study on How to Build a User-centered·Field-oriented Ship-communication Test Environment(Living Lab) (사용자 중심의 선박통신 현장 시험 환경(Living Lab) 구축 방안 연구)

  • Sangjin JANG;Bu-Young KIM;Hyo-Jeong KIM;Si-Hwan LEE;Taehan SONG;Woo-Seong Shim
    • Journal of Navigation and Port Research
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    • v.47 no.6
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    • pp.394-400
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    • 2023
  • Unlike advancements on land, the maritime industry has been slow to embrace new technologies, primarily due to user apprehension toward unproven innovations in the development process. The existing paradigm of technology development, marked by expert-oriented and laboratory-centric test environments, often leads to a stagnation of progress at the research stage, as the applicability of the technology remains uncertain. This study departed from the conventional research system and introduced a novel methodology known as a "living lab." This approach aimed to ensure applicability by actively involving field-oriented users throughout the entire lifecycle of technology development, encompassing planning, development, verification, and evaluation. The presentation of a plan for the construction and operation of such a living lab in this study is expected to contribute to establishing an efficient experimentation system for ships that can reflect user opinions in the future and to secure technology applicability in the maritime field.

A sea trial method of hull-mounted sonar using machine learning and numerical experiments (기계학습 및 수치실험을 활용한 선체고정형소나 해상 시운전 평가 방안)

  • Ho-seong Chang;Chang-hyun Youn;Hyung-in Ra;Kyung-won Lee;Dea-hwan Kim;Ki-man Kim
    • The Journal of the Acoustical Society of Korea
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    • v.43 no.3
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    • pp.293-304
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    • 2024
  • In this paper, efficient and reliable methodologies for conducting sea trials to evaluate the performance of hull-mounted sonar systems is discussed. These systems undergo performance verification during ship construction via sea trials. However, the evaluation procedures often lack detailed consideration of variabilities in detection performance due to seabed topography, seasonal factors. To resolve this issue, temperature and salinity structure data were collected from 1967 to 2022 using ARGO floats and ocean observers data. The paper proposes an efficient and reliable sea trial method incorporating Bellhop modeling. Furthermore, a machine learning model applying a Physics-Informed Neural Networks was developed using the acquired data. This model predicts the sound speed profile at specific points within the sea trial area, reflecting seasonal elements of performance evaluation. In this study, we predicted the seasonal variations in sound speed structure during sea trial operations at a specific location within the trial area. We then proposed a strategy to account for the variability in detection performance caused by seasonal factors, using results from Bellhop modeling.

E-Commerce in the Historical Approach to Usage and Practice of International Trade ("무역상무(貿易商務)에의 역사적(歷史的) 어프로치와 무역취인(貿易取引)의 전자화(電子化)")

  • Tsubaki, Koji
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.19
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    • pp.224-242
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    • 2003
  • The author believes that the main task of study in international trade usage and practice is the management of transactional risks involved in international sale of goods. They are foreign exchange risks, transportation risks, credit risk, risk of miscommunication, etc. In most cases, these risks are more serious and enormous than those involved in domestic sales. Historically, the merchant adventurers organized the voyage abroad, secured trade finance, and went around the ocean with their own or consigned cargo until around the $mid-19^{th}$ century. They did business faceto-face at the trade fair or the open port where they maintained the local offices, so-called "Trading House"(商館). Thererfore, the transactional risks might have been one-sided either with the seller or the buyer. The bottomry seemed a typical arrangement for risk sharing among the interested parties to the adventure. In this way, such organizational arrangements coped with or bore the transactional risks. With the advent of ocean liner services and wireless communication across the national border in the $19^{th}$ century, the business of merchant adventurers developed toward the clear division of labor; sales by mercantile agents, and ocean transportation by the steam ship companies. The international banking helped the process to be accelerated. Then, bills of lading backed up by the statute made it possible to conduct documentary sales with a foreign partner in different country. Thus, FOB terms including ocean freight and CIF terms emerged gradually as standard trade terms in which transactional risks were allocated through negotiation between the seller and the buyer located in different countries. Both of them did not have to go abroad with their cargo. Instead, documentation in compliance with the terms of the contract(plus an L/C in some cases) must by 'strictly' fulfilled. In other words, the set of contractual documents must be tendered in advance of the arrival of the goods at port of discharge. Trust or reliance is placed on such contractual paper documents. However, the container transport services introduced as international intermodal transport since the late 1960s frequently caused the earlier arrival of the goods at the destination before the presentation of the set of paper documents, which may take 5 to 10% of the amount of transaction. In addition, the size of the container vessel required the speedy transport documentation before sailing from the port of loading. In these circumstances, computerized processing of transport related documents became essential for inexpensive transaction cost and uninterrupted distribution of the goods. Such computerization does not stop at the phase of transportation but extends to cover the whole process of international trade, transforming the documentary sales into less-paper trade and further into paperless trade, i.e., EDI or E-Commerce. Now we face the other side of the coin, which is data security and paperless transfer of legal rights and obligations. Unfortunately, these issues are not effectively covered by a set of contracts only. Obviously, EDI or E-Commerce is based on the common business process and harmonized system of various data codes as well as the standard message formats. This essential feature of E-Commerce needs effective coordination of different divisions of business and tight control over credit arrangements in addition to the standard contract of sales. In a few word, information does not alway invite "trust". Credit flows from people, or close organizational tie-ups. It is our common understanding that, without well-orchestrated organizational arrangements made by leading companies, E-Commerce does not work well for paperless trade. With such arrangements well in place, participating E-business members do not need to seriously care for credit risk. Finally, it is also clear that E-International Commerce must be linked up with a set of government EDIs such as NACCS, Port EDI, JETRAS, etc, in Japan. Therefore, there is still a long way before us to go for E-Commerce in practice, not on the top of information manager's desk.

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