• Journal of Advanced Navigation Technology
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• v.25 no.6
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• pp.523-529
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• 2021

This paper shows the design and fabrication of antenna embedded in marine buoy for marine IoT service, especially automatic identification system of fishing gears. Frequency band of proposed antenna has dual band of 433 MHz and 920 MHz considering marine IoT extension. Dual pattern monopole type for 920 MHz and meander type for 433 MHz are adopted in the proposed antenna. Voltage standing wave ratio is obtained 1.548 at 433 MHz and obtained 1.5 of mean value at 920 MHz band by measuring the fabricated antenna. The maximum antenna gain of 3.83 dBi is measured at 902 MHz among 920 MHz band, while antenna gain of 433 MHz is obtained 1.18 dBi. Although antenna gain of 433 MHz is low than 920 MHz band, this gain is larger than desired value of -5 dBi. And, it is confirmed that other measured values meet the performance criteria for archiving communication distance of 10 km between marine buoy and fishing ship in automatic identification system of fishing gears.

• The Journal of the Acoustical Society of Korea
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• v.43 no.4
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• pp.383-390
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• 2024

When measuring the radiated noise of an underwater vehicle, the range information between the vehicle and the receiver is an important factor, but since Global Positioning System (GPS) is not available in underwater, an alternative method is needed. As an alternative, the range is measured by estimating the arrival time, arrival time difference, and arrival frequency difference using a separate acoustic signal. However, errors occur due to the channel environment, and these outliers become obstacles in continuously measuring range. In this paper, we propose a method to reduce errors by curve fitting with a function in the form of a V-curve as a post-processing to remove outliers that occurred in the process of measuring range information. Simulation, lake and sea trials were conducted to verify the performance of the proposed method. In the results of the lake trial, the range estimation error was reduced by about 85 % from the Root Mean Square Error (RMSE) point of view.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.1
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• pp.57-63
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• 2015

Foreign seafarers have embarked on the fishing vessels as industrial trainees since 1990s and the total number of foreign seafarers on merchant ships and fishing vessels marked 21,327 as of the end of 2013. Especially, in case of deep-sea fishing vessels and coastal/inshore fishing vessels, although the number of fishing vessels decreased, the number of foreign seafarers nearly doubled during recent 5 years. Looking at the marine accidents occurred to fishing vessels, after multinational seafarers are joining on board fishing vessels, difficulties in communication among seafarers has become a major issue. And the safety rules which could be understandable by foreign seafarers are not provided and the education and training for foreign seafarers are not properly conducted either. Consequently, the risk of marine accidents during fishing operation on fishing vessels has increased and emergency response under the captain's control was not effective enough to cope with such emergency situation. Several forced labour issues were also reported resulting from abusive words and assault committed by Korean seafarers. Therefore, This study aims first to review the cases of marine accidents on board fishing vessels which foreign seafarers are working and, the problems concerning employment and education for those foreign seafarers, and then to point out the necessity of conducting training on the safety rules and regular emergency drills for the foreign seafarers in order to prevent marine accidents.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.7
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• pp.1021-1029
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• 2018

The marine buoys are operated in various domains, which are navigation route and danger maker, weather and environment monitoring, military strategical element, etc. If the marine buoy is damaged, there consumes many cost and time for recovery or replacement, because of severe environmental condition, and causes a risk possibility of secondary accident. In this paper, we developed an active monitoring and approach alarm providing system using trail cameras and AIS for protection for the marine buoys. To do this, we analyzed existing researches and similar systems, extracted requirements for enhancement, and designed the system architecture that applied the enhanced elements. The main considerations of system enhancement are: integration of AIS and trail cameras, adopting of phased alarm technique by approaching ships, applying of selective communication module, conducting the image processing of ships for providing alarm, and applying thermal cameras. After that, we developed the system using designed architecture and verified effectiveness of the system based on laboratory or field-level tests.

• Journal of Navigation and Port Research
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• v.46 no.3
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• pp.179-190
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• 2022

In this study, we investigated the characteristic impedance and bandwidth of CPW3DCS (coplanar waveguide employing periodic 3D coupling structures), and examined its potential for the development of a marine radio communication FISoC (fully-integrated system on chip) semiconductor device. To extract bandwidth and characteristic impedance of the CPW3DC, we induced a measurement-based equation reflecting measured insertion loss, and compared the measured results of the propagation constant β and characteristic impedance with the measured ones. According to the results of the comparison, the calculated results show a good agreement with the measured ones. Concretely, the propagation constant β and characteristic impedance exhibited an maximum error of 3.9% and 6.4%, respectively. According to the results of this study, in a range of LT = 30 ~ 150 ㎛ for the length of periodic structures, the CPW3DC exhibited a passband characteristic of 121 GHz, and a very small dependency of characteristic impedance on frequency. We could realize a low impedance transmission line with a characteristic impedance lower than 20 Ω by using CPW3DCS with a line width of 20 ㎛, which was highly reduced, compared with a 3mm line width of conventional transmission line with the same impedance. The characteristic impedance was easily adjusted by changing LT. The above results indicate that the CPW3DC can be usefully used for the development of a wireless communication FISoC (fully-integrated system on chip) semiconductor device. This is the first report of a study on the bandwidth of the CPW3DC.

• Journal of Arbitration Studies
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• v.12 no.1
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• pp.271-321
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• 2002

Every year, many million of business transactions take place. Ocassionally, disagreements develop over these business transactions. Many of these disputes are resolved by mediation, arbitration and out-of-court settlement options. The American Arbitration Association(AAA) helps resolve a wide range of disputes through mediation, arbitration, elections and other out-of-court settlement procedures. The AAA offers a broad range of dispute resolution services to business executives, attorneys, individuals, trade associations, unions, management, consumers, families, communities, and all level of governments. The 198,491 cases composed of the 194,303 arbitration cases and the 4,188 mediation cases, were filed with the AAA in 2000. These case filings represent a full range of matters, including commercial finance, construction, labor and employment, environmental, health care, insurance, real state, securities, and technology disputes. The Korean Commercial Arbitration Board (KCAB) does more than render arbitration services. It helps facilitate settlements and guarantee implementation thereof between trading partners at home and abroad involving disputes related to such areas as the sale of commodities, construction, joint venture agreements, technical assistance, agency agreements, and maritime transport. The 643 cases composed of the the 197 arbitration cases and the 446 mediation cases, were filed with the KCAB in 2001. There are some differences between the AAA and the KCAB regarding the number and the area of mediation and arbitration case filings, the breath of service offerings, the scope of alternative dispute resolution, and the education and training. In order to apply to the proceedings of the commercial mediation and arbitration, the AAA has the Commercial Mediation Rules, the Commercial Arbitration Rules, the Expedited Procedures, the Optional Procedures for Large, Complex Commerical Dispute, and the Optional Rules for Emergency Measures of Protection as amended and effective on September 1, 2000. In order to apply to the proceedings of commercial arbitration, the KCAB has the Arbitration Rules as amended by the Supreme Court on April 27, 2000, which have been changed to incorporate the revisions of the Arbitration Act that went into effect on December 31, 1999. There are some differences between the AAA's commercial Arbitration Rules and the KCAB's Arbitration Rules regarding the clauses of jurisdiction and administrative conference, number of arbitrators, communication with arbitrator, vacancies, preliminary hearing, exchange of information, oaths, evidence by affidavit and posthearing filing of documents or others, interim measures, serving of notice, form of award, scope of award, delivery of award to parties, modification of award, release of liability, administrative fees, neutral arbitrator's compensation, and expedited procedures. In conclusion, for the vitalization of KCAB and its ADR system, the following measures should be taken : the effective case management, the development of on0-line ADR, the establishment of ADR system of electronic commerce disputes, and the variety of dispute resolution rules in each expert field.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.9
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• pp.1822-1829
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• 2016

DGPS Reference station is established in Korea for improvement of GPS navigation accuracy and needs of integrity. Recently, DGPS stations provide user positioning information on land as well as ocean. However, this paper investigated visibility and interference environment for performance degradation of Chung-ju DGPS reference station. In case of Young-do reference station, visibility and interference environment were satisfied with reference standard. In case of Chung-ju reference station, visibility was satisfied with 7 degree elevation angle. However, interference environment was not satisfied with reference standard of -50dBm. This paper proposed time differential measurement analysis method excluding error of signal noise for analyzing measurement error. Chung-ju reference station measurement analysis result is three times the error than on Young-do in Dec, 2015. In addition, this paper has confirmed measurement performance degradations because of reference station equipment problem. Future study will be carried out performance analysis of 17 DGPS reference station.

• Strategy21
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• s.31
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• pp.85-119
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• 2013

This paper asks whether the Republic of Korea (ROK) Navy should continue to focus on building ocean-going naval ships when it faces the threats of North Korean provocations in littoral areas. My position is that the ROK Navy should keep pursuing ocean-going capabilities. I provide explanations why it should do so from the perspectives of three important dimensions: capability, doctrine, and organizational identity. First, I argue that the distinction between a littoral navy and an ocean-going navy is an unnecessary dichotomy. It may lead to inefficiency in national security. The military posture should be designed in a way that it can address all external threats to national security regardless of whether they are from North Korea or not. Such capability is the one that the ROK Navy has tried to acquire with the 'Blue Water Navy' initiative since the 1990s. Second, also from the perspective of lately developed military doctrines that emphasize jointness and precision strike capability, ocean-going capabilities such as the mobile task fleet program have become a must, not an option, given today's security situations on and around the Korean peninsula. Lastly, I draw attention to the fact that the 'Blue Water Navy (BWN)' initiative meant more than just capability to the ROK navy. The BWN represents the ROK navy's organizational identity that the navy has defined since the 1980s as it emphasized promoting national interest and international standing as part of its organizational essence. Furthermore, the phrase 'blue water navy' took on symbolic meanings to the people that are associated with South Korean-ness including sovereignty, national pride, standing in the world and hopes for the future. Since 1990s, many scholars and experts have made the case for the necessity of improving South Korea's naval capability based on different rationales. They emphasized the protection of Sea Lines of Communication (SLOCs), the economic value of the sea, the potential danger associated with territorial disputes over islands, and increasing naval power of neighboring countries since the end of the Cold War. This paper adds to this debate by trying to explain the matter with different factors including naval doctrines and organizational identity. Particularly, this paper constitutes a unique endeavor in that it incorporating constructivist elements (that is, identity politics) in explaining a national security matter.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.5
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• pp.481-488
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• 2013

Nitric oxide ($NO_x$) formation characteristics in non-premixed diffusion flames of methane fuels have been investigated experimentally and numerically by adding 10% ammonia to the fuel stream, according to the variation of the oxygen ratio in the oxidizer with oxygen/carbon dioxide and oxygen/nitrogen mixtures. In an experiment of coflow jet flames, in the case of an oxidizer with oxygen/carbon dioxide, the $NO_x$ emission increased slightly as the oxygen ratio increased. On the other hand, in case of an oxygen/nitrogen oxidizer, the $NO_x$ emission was the maximum at an oxygen ratio of 0.7, and it exhibited non-monotonic behavior according to the oxygen ratio. Consequently, the $NO_x$ emission in the condition of oxyfuel combustion was overestimated as compared to that in the condition of conventional air combustion. To elucidate the characteristics of $NO_x$ formation for various oxidizer compositions, 1D and 2D numerical simulations have been conducted by adopting one kinetic mechanism. The result of 2D simulation for an oxidizer with oxygen/nitrogen well predicted the trend of experimentally measured $NO_x$ emissions.

• The Journal of the Korea Contents Association
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• v.20 no.7
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• pp.56-65
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• 2020

The purpose of this research is to study the excellence and originality of the Joseon artillery(Jungwan-gu) through an effective restoration. Jungwan-gu that was used during the Japanese Invasion of Korea in 1592 was able to maintain its maritime dominance based on cutting-edge technology of its time. Joeson artillery(Jungwan-gu) was used in major naval/land battles during the Japanese Invasion of Korea in 1592 and is an important cultural heritage that provides a glimpse into Joeson people's will to defend the nation from foreign invasion. For further historical verification such as operational method of Jungwan-gu, extensive research in various fields including size, proportions, structure, materials, and casting method were required. Accordingly, for a more effective research on Jungwan-gu, cutting-edge technologies such as 3D scanning and 3D printing were utilized. Firstly, 3D scanning, modeling, and printing technology were applied to identify the morphological characteristics of Jungwan-gu. Through this, we were able to reach our research objective of identifying the size, internal structure, and proportionality of Jungwan-gu. In addition, by studying the form, operation, casting methods, and other characteristics, the restoration of Jungwan-gu provided us with an important opportunity to verify the dominance and originality of the Joeson era's science and technology during the Japanese Invasion of 1592. This reaserch subject participated in the "4th 3D printing BIZCON Contest" and won the Minister Prize of Science and Technology Information and Communication.