• Journal of Navigation and Port Research
• /
• v.46 no.1
• /
• pp.18-25
• /
• 2022

MOF strengthen the law and institutions for safety management after the capsize accident of passenger ship "Sewol" on April 16, 2014. Nevertheless, about 13 cases of marine accidents such as collisions, contact, and stranding have occurred in coastal passenger ships over the past 5 years. Particularly, according to the judgment of KMST, most of the main causes of passenger ship accidents occurred within harbor areas because of the master's improper ship-handling or inattention. And so, this study analyzed four cases of marine accidents on passenger ships that occurred in the port areas and examined the environmental, institutional, material, and human factors that contributed to the master's improper ship-handling and behavior, and the results are as follows. First, as an environmental factor, the size of the turning basin was not enough. Second, as an institutional factor, the VTS control was not properly supported, the master lacked sufficient training for safe ship-handling in the port area and up-to-date charts were not provided. Third, as a material factor, the digital type speed log capable of the ship's speed in real-time was not installed on the ship's wing bridge. Lastly, as a human factor, the master could not take proper bridge resources and the passage plan was not proper. Therefore, it is suggested in this paper that the size of the turning basin should be adjusted to meet the prescribed standards, the master of passenger ships should receive the ship-handling simulation training among other safety training to ensure safe ship-handling of the master in the port area as improvement measures.

• The Korean Journal of Air & Space Law and Policy
• /
• v.26 no.2
• /
• pp.3-39
• /
• 2011

People may operate unmanned aerial vehicles (UAVs or drones) thousands of miles from the drone's location. Drones were first used (like balloons) for surveillance. By 2001, the United States began arming drones with missiles and using them to strike targets during combat in Afghanistan. By mid-2010, over forty states and other entities possessed drones, many with the capability of launching missiles and dropping bombs. Each new development in military weapons technology invites assessment of the relevant international law. This Insight surveys the international law applicable to the recent innovation of weaponizing drones. In determining what international law rules govern drone use, the most salient feature is not the fact that drones are unmanned. The fact drones carry no human operator may be the most important new technological breakthrough, but the key feature for international law purposes is the type of weaponry drones carry. Whether law enforcement rules govern drone use depends on the situation and not necessarily who is operating the drone. Battlefield weapons may also be lawfully used before an armed conflict in the following situations: when initiating self-defense under Article 51 of the United Nations Charter; when authorized by the UN Security Council; when a government seeks to suppress internal armed conflict; and, perhaps, when a state is invited to assist a government in suppressing internal armed conflict. The rules governing resort to force in self-defense are found in Article 51 of the UN Charter and a number of decisions by international courts and tribunals. Commentators continue to debate whether drone technology represents the next revolution in military affairs. Regardless of the answer to that question, drones have not created a revolution in legal affairs. The current rules governing battlefield launch vehicles are adequate for regulating resort to drones. More research must be undertaken, however, to understand the psychological effects of deploying unmanned vehicles and the effects on drone operators of sustained, close visual contact with the aftermath of drone attacks.

• Journal of Korean Society of Transportation
• /
• v.23 no.8 s.86
• /
• pp.7-17
• /
• 2005

Transportation is from an individual mobility. Various efforts to propose specific values or the individual mobility have been conducted in diverse transportation environment. However, mobility studies for multimodal public transportation are rare especially on not the range of line but area. This study propose a method to calculate transit mobility indices as expanding mobility analysis from point-to-point to area-to-area, considering access time to transit facility, running time and transfer time of passengers. To extract mobility indices, we included walking as a lowest category of mode and set passenger car as a competitive mode to transit mode. This study propose three public transportation mobility indices as 1) how competitive public transportation facility is offered against passenger car 2) how convenient transit mode including walking is provided against passenger car from origin to destination and 3) how many various paths are presented to support passenger's travel between regions. These indices are tested on the Seoul metropolitan area with 10 lines of urban rail and about 420 lines of bus. In addition, we proposed two political applications of proposed mobility indices to increase public transportation mobility between two regions and to maximize the mobility of study area when a line is added in the area.

• Korean Journal of Remote Sensing
• /
• v.31 no.3
• /
• pp.215-226
• /
• 2015

Normally, aero photography using UAV uses about 430 MHz bandwidth radio frequency (RF) modem and navigates and remotely controls through the connection between UAV and ground control system. When using the exhausting method, it has communication range of 1-2 km with frequent cross line and since wireless communication sends information using radio wave as a carrier, it has 10 mW of signal strength limitation which gave restraints on life my distance communication. The purpose of research is to use communication technologies such as long-term evolution (LTE) of smart camera, Bluetooth, Wi-Fi and other communication modules and cameras that can transfer data to design and develop automatic shooting system that acquires images to UAV at the necessary locations. We conclude that the android based UAV filming and communication module system can not only film images with just one smart camera but also connects UAV system and ground control system together and also able to obtain real-time 3D location information and 3D position information using UAV system, GPS, a gyroscope, an accelerometer, and magnetic measuring sensor which will allow us to use real-time position of the UAV and correction work through aerial triangulation.

• Korean journal of applied entomology
• /
• v.17 no.3 s.36
• /
• pp.149-154
• /
• 1978

Varietal resistance of 49 strawberry varieties to two isolates of Mycosphaerella fragariae was investigated by incoulation experiments and its chemical control was also studied. 1. The susceptibility of varieties and pathogenecity of the isolates were significantly different. 2. in most instances isolate $S_3$ and the reactions of varieties to the isolates were different. 3. Among the varieties tested, Tioga, Donner, Marhall, Northwest, Red star, Senga, sengana, Shasta, Torrey, Hokowase and Daehak No. 1 were found highly susceptible to isolate $K_2$, and America, Dabreak, Takanae, Kurumae No. 103, Horida's wander, Benizuru, Hukuba and Himiko were found as highly resistant. 4. It was apparent that America, Morioka No. 17, Takanae, Kurumae No. 13, Horida's wander, Benizuru and Hukuba were resistant to isolate $S_3$ and Marshall, Tioga were very susceptible to it. 5. As for the susceptibility of varieties by old End new leaf to isolate $K_2$, old leaves were evaluated as highly resistant. 6. Under the conditions of artificial infection Captan was the most effective in controlling for the leafspot and followed by Zineb and Difolatan.

• Ecology and Resilient Infrastructure
• /
• v.9 no.2
• /
• pp.83-92
• /
• 2022

The 2020 summer extreme flood severely disturbed the riparian ecosystem of the Seomjin River. Some trees were killed by the flood impact, whereas others have recovered through epicormic regeneration after the disturbance. At the same time, several tree individuals newly germinated. This research aimed to explain the recovery of the riparian ecosystem by spatial proximity between each tree individual of different characteristics, such as "dead", "recovered", and "newly germinated". A spatial point pattern analysis based on K and g-functions revealed that the newly germinated trees and the existing trees were distributed in the spatially clumping patterns. However, further detailed analysis revealed that the new trees were statistically less attracted to the recovered trees than the dead trees, implying competitive interactions hidden in the facilitative interactions. Habitat amelioration by the existing trees positively affected the growth of the new trees, while "living" existing trees were competing with the new trees for resources. This research is expected to provide new knowledge in this era of rapid climate change, which likely induces stronger and more frequent natural disturbance than before. Environmental factors have been widely used for ecosystem modeling, but species interactions, represented by the relative spatial distribution of plant individuals, are also valuable factors explaining ecosystem dynamics.

• Journal of the HCI Society of Korea
• /
• v.9 no.2
• /
• pp.13-21
• /
• 2014

Jump-rope is a simple and effective exercise, but its intensive exercise load and monotonous pattern make it difficult to perform consistent workout. On the other hand, jumping rope accompanies large amount of kinetic energy which can be converted into electrical energy. In this study, we designed and implemented a self-powered jump-rope which can support the low-power embedded Bluetooth system inside it. The embedded system wirelessly transmits the acceleration data measured during jumping-rope exercise to a smartphone. We also developed a smartphone app which can count the number of jumps and provide real-time feedback with sound and animated graphic effects in a game context. Pilot test using the prototype smart jump-rope verified that it can be useful to motivation for the jump-rope exercise and make the exercise more effective by providing users with precise information about their exercise. We expect that the developed self-powered jump-rope will change the exercise from an intensive physical activity into electricity-generating fun experience combined with smartphone game, which maximize the benefit of the consistent jump-rope exercise.

• Proceedings of the Korean Aquaculture Society Conference
• /
• 2003.10a
• /
• pp.86-87
• /
• 2003

본 실험은 전복 종묘생산 시 먹이생물로 적합한 부착 규조를 파악하기 위하여 실시하였다. 부경대학교 한국해양 미세 조류 은행에서 보유한 부착 규조종 중, 해역, 크기, 부착력, 영양분석 결과를 고려하여, 11종의 부착 규조를 선택하였다. 각 부착 규조를 f/2 배지로 파판에 배양 한 후 평균 각장 7mm의 까막전복 치패를 대상으로 26일 간 먹이 효율을 조사하였다. 또 이 실험의 결과를 토대로 먹이 효율이 좋은 4종의 부착 규조를 선택하여 참전복 유생의 부착율과 먹이 효율을 조사하였다. 참전복 유생은 수정 후 56 시간이 지난 veliger유생을 이용하여 각 규조에 따른 유생의 부착율, 사망률, 변태율, 성장률을 측정하였다. 까막전복 치패를 대상으로 규조종별 먹이 효율을 실험한 결과, 생존율은 Caloneis schroder가 37.1%, Nitzchia sp. 35.0%, Navicula sp.가 31.4%로 대체로 높은 생존율을 보인 반면에, Navicula elegans이 6.4%, Cylidrotheca closterium.은 11.7%로 낮은 생존율을 보였다. 실험 종료후, 까막전복 각장의 성장을 측정한 결과, Cocconeis californica가 9.33 mm, Achnanthes sp.은 9.27 mm으로 대체로 높은 성장을 보였다. 이에 반해 Navicula elegans은 8.60 mm으로 낮은 성장을 보였다. 전복 전중과 육중은 Amphora sp.에서 각각 87.7mg, 35.2mg 으로 가장 높았으며, Cocconeis californica와 Achnanthes sp.에서도 대체적으로 높게 나타났다. Navicula elegans는 각장의 성장에서와 같이 가장 낮은 증육을 보였다. 규조 4종을 대상으로 한 참전복 유생의 부착율 에서는 수정 후 152시간 후 Cocconies califonica에서 47.3%로 가장 높은 반면, Caloneis schroder 에서 23.8%로 가장 낮았다. 실험 9일째 사망률은 Cocconeis californica에서 63.6%로 가장 낮게 나타났고, Nitzchia sp.에서 90.4%로 가장 높게 나타났다. 유생의 변태율은 Cocconeis californica에서 98.5%로 가장 높은 결과를 보였다. 유생의 일간 성장율 역시 Cocconeis californica에서 25.4 $\mu\textrm{m}$/day로 높았고, Nitzchia sp.에서 13.9 $\mu\textrm{m}$/day로 낮았다. 실험 24일째 참전복 유생의 최종 생존율은 변태율과 일간 성장률이 높았던, Cocconeis californica에서 7.8%로 가장 높게 나타났다.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.37 no.4
• /
• pp.406-412
• /
• 2009

Flight simulation model for helicopter simulator is one of the most important models which affect flight performance and handling quality. It is typical to develop the model based on the raw data and models from the helicopter designers/manufacturers. The approaches in this study were to develop the basic model based on the available resources regarding helicopter operation/maintenance and to tune and validate it based on the flight test results. The basic model was developed with maintenance manuals, flight manuals, analyses, measurements, papers and so on considering that KA-32T data could not be obtained from the manufacturer. The flight test for KA-32T was performed and the reference data for the simulation validation tests were acquired. The flight simulation model was validated to have the fidelity compatible with level C of FAA AC120-63 after comparison and tuning with flight test results.

• Journal of the Korean Wood Science and Technology
• /
• v.39 no.4
• /
• pp.370-380
• /
• 2011

This study was carried out to investigate the properties of soils in the sampling green tea farms and the chemical constituents of the green tea leaves at the 3 harvest stages (Ujeon ${\rightarrow}$ Sejag ${\rightarrow}$ Jungjag). The results as follows; The properties of the soils were sandy loam, loam, well drained and fertile-rich in phosphoric acids in general. The contents of chlorophyll, tannin, vitamin-c and total catechin were increased as harvest periods getting late but the contents of total nitrogen, free amino acids, theanine, caffeine were decreased on the reverse. The inorganic constituents Mg, Ca and Mn were increased as harvest periods getting late but the Na, K, B contents were decreased on the reverse. The contents of the total nitrogen, chlorophyll, total free amino acid, theanine, caffeine and total catechin and Na, Mg, Ca, B and Se were insignificant differences between Ujeon and Sejag.