• Journal of Internet Computing and Services
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• 제22권6호
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• pp.25-32
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• 2021

In line with future changes in the marine environment, Aids to Navigation has been used in various fields and their use is increasing. The term "Aids to Navigation" means an aid to navigation prescribed by Ordinance of the Ministry of Oceans and Fisheries which shows navigating ships the position and direction of the ships, position of obstacles, etc. through lights, shapes, colors, sound, radio waves, etc. Also now the use of Aids to Navigation is transforming into a means of identifying and recording the marine weather environment by mounting various sensors and cameras. However, Aids to Navigation are mainly lost due to collisions with ships, and in particular, safety accidents occur because of poor observation visibility due to sea fog. The inflow of sea fog poses risks to ports and sea transportation, and it is not easy to predict sea fog because of the large difference in the possibility of occurrence depending on time and region. In addition, it is difficult to manage individually due to the features of Aids to Navigation distributed throughout the sea. To solve this problem, this paper aims to identify the marine weather environment by estimating sea fog level approximately with images taken by cameras mounted on Aids to Navigation and to resolve safety accidents caused by weather. Instead of optical and temperature sensors that are difficult to install and expensive to measure sea fog level, sea fog level is measured through the use of general images of cameras mounted on Aids to Navigation. Furthermore, as a prior study for real-time sea fog level estimation in various seas, the sea fog level criteria are presented using the Haze Model and Dark Channel Prior. A specific threshold value is set in the image through Dark Channel Prior(DCP), and based on this, the number of pixels without sea fog is found in the entire image to estimate the sea fog level. Experimental results demonstrate the possibility of estimating the sea fog level using synthetic haze image dataset and real haze image dataset.

• The Korean Journal of Air & Space Law and Policy
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• 제24권2호
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• pp.139-161
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• 2009

The idea of establishing an International Court of Air and Space Law (hereinafter referred to ICASL) is only my academic and practical opinion as first proposal in the global community. The establishment of the International Court of Air and Space Law can promote the speed and promote fairness of the trial in air and space law cases. The creation of an ICASL would lead to strengthening of the international cooperation deemed essential by the global community towards joint settlement in the transnational air and space cases, claims and would act as a catalyst for the efforts and solution on aircraft, satellite and space shuttle's accidents and cases and all manpower, information, trial and lawsuit to be centrally managed in an independent fashion to the benefit of global community. The aircraft, satellite and spacecraft's accidents attributes to the particular and different features between the road, railway and maritime's accidents. These aircraft, satellite and spacecraft's accidents have incurred many disputes between the victims and the air and space carriers in deciding on the limited or unlimited liability for compensation and the appraisal of damages caused by the aircraft's accidents, terror attack, satellite, space shuttle's accidents and space debris. This International Court of Air and Space Law could hear any claim growing out of both international air and space crash accidents and transnational accidents in which plaintiffs and defendants are from different nations. This alternative would eliminate the lack of uniformity of decisions under the air and space conventions, protocols and agreements. In addition, national courts would no longer have to apply their own choice of law analysis in choosing the applicable liability limits or un-limit for cases that do not fall under the air and space system. Thus, creation of an International Court of Air and Space Law would eliminate any disparity of damage awards among similarly situated passengers and shippers in nonmembers of air and space conventions, protocols, agreements and cases. Furthermore, I would like to explain the main items of the abovementioned Draft for the Convention or Statute of the International Court of Air and Space Law framed in comparison with the Statute of the International Court of Justice, the Statue of the International Tribunal for the Law of the Sea and the Statute of the International Criminal Court. First of all, in order to create the International Court of Air and Space Law, it is necessary for us to legislate a Draft for the Convention on the Establishment of the International Court of Air and Space Law. This Draft for the Convention must include the elected method of judges, term, duty and competence of judge, chambers, jurisdiction, hearing and judgment of the ICASL. The members of the Court shall be elected by the General Assembly and Council of the ICAO and by the General Assembly and Legal Committee of the UNCOPUOS from a list of persons nominated by the national groups in the six continent (the North American, South American, African, Oceania and Asian Continent) and two international organization such as ICAO and UNCOPUOS. The members of the Court shall be elected for nine years and may be re-elected as one time. However, I would like to propose a creation an International Court of Air and Space Law in extending jurisdiction to the International Court of Justice at the Hague to in order to decide the air and space convention‘s cases. My personal opinion is that if an International Court on Air and Space Law will be created in future, it will be settled quickly and reasonably the difficulty and complicated disputes, cases or lawsuit between the wrongdoer and victims and the injured person caused by aircraft, satellite, spacecraft's accidents or hijacker and terrorists etc. on account of deciding the standard of judgment by judges of that’s court. It is indeed a great necessary and desirable for us to make a new Draft for the Convention on a creation of the International Court of Air and Space Law to handle international air and space crash litigation. I shall propose to make a new brief Draft for the Convention on the Creation of an International Court of Air and Space Law in the near future.

• Journal of Preventive Medicine and Public Health
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• 제15권1호
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• pp.187-196
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• 1982

The followings are the results of the study on industrial accidents occurred at 12 factories manufacturing metal products during the period of 2 years from January 1980 to December 1981 in the area of Yong-Dung-Po in Seoul. The results of the study are as follows: 1. The incidence rate of industrial injuries was 45.7 per 1,000 workers of the sample group and the rate of male (54.0) was three times higher than that of female (17.5). 2. In age groups, the highest rate was observed in the group of under 19 years old with 83.5, while the lowest in the group of 40s. 3. It was found that those who had short term of work experience produced a higher rate of injuries, particularly, the group of workers with less than 1 year of experience showed the highest rate of it as 48.1%. 4. In working time, the highest incidence rate occurred 3 and 7 hours after the beginning of their working showing the rate of 6.0 and 6.1 per 1,000 workers, respectively. 5. The highest incidence rate was observed on Monday as 8.4 per 1,000 workers, and it was 18.3% in aspect of the days of a week. 6. In aspect of the months of a year, the highest incidence was observed on July 1,000 workers and the next was on March as 4.8. These figures account for 11.8% of total occurrence in respective month. as 5. 4 per and 10.5% 7. In causes of injuries, the accident caused by power driven machinery showed the highest rate with 37.5%, the second was due to handling without machinery with 17.2%, and the third was due to falling objects with 14.2%, and striking against objects with 10.2%, and so on. 8. By parts of the body affected, the most injuries 84.3% of them occurred on both upper and lower extremities with the rate of 58.8% for the former and 25.5% for the latter. Fingers were most frequently injured with a rate of 40.3%. Comparing the sites of extremities affected, rate of injuries on the right side was 55.0% and 45.0% on the left side. 9. In the nature of injury, laceration and open wound were the highest with 34. 0%, the next was fracture and dislocation with 31. 9%, and sprain was the third with 8.1%. 10. On the duration of treatment, it lasted less than one month in 68.9% of the injured cases, of which 14.5% of the cases were recovered within 2 weeks, and 54.4% of them were treated more than 2 weeks. And the duration of the treatment tended to be prolonged in larger industries. 11. The ratio of insured accidents to uninsured accidents was 1 to 4.7.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제33권5호
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• pp.455-462
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• 2000

The objective of this study was to examine the physicochemical characteristics of coagulation reaction between loess and red tide organisms (RTO) and its feasibility, in developing a technology for the removal of RTO bloom in coastal sea. The physicochemical characteristics of loess were examined for a particle size distribution, surface characteristics by scanning electron microscope, zeta potential, and alkalinity and pH variations in sea water. Two kinds of RTO that were used in this study, Cylindrothen closterium and Skeietonema costatum, were sampled in Masan bay and were cultured in laboratory. Coagulation experiments were conducted using various concentrations of loess, RTO, and a jar tester. The supernatant and RTO culture solution were analyzed for pH, alkalinity, RTO cell number. A negative zeta potential of loess increased with increasing pH at $10^(-3)M$ NaCl solution and had -71.3 mV at pH 9.36. Loess had a positive zeta potential of +1,8 mV at pH 1.98, which resulted in a characteristic of material having an amphoteric surface charge. In NaCl and $CaCl_2$, solutions, loess had a decreasing negative zeta potential with increasing $Na^+\;and\;Ca^(+2)$ ion concentration and then didn't result in a charge reversal due to not occurring specific adsorption for $Na^+$ ion while resulted in a charge reversal due to occurring specific adsorption for $Ca^(+2)$ ion. In sea water, loess and RTO showed the similar zeta potential values of -112,1 and -9.2 mV, respectively and sea sand powder showed the highest zeta potential value of -25.7 mV in the clays. EDLs (electrical double-layers) of loess and RTO were extremely compressed due to high concentration of salts included in sea water, As a result, there didn't almost exist EDL repulsive force between loess and RTO approaching each other and then LVDW (London-yan der Waals) attractive force was always larger than EDL repulsive force to easily form a floe. Removal rates of RTO exponentially increased with increasing a loess concentration. The removal rates steeply increased until $800 mg/l$ of loess, and reached $100{\%}$ at 6,400 mg/l of loess. Removal rates of RTO exponentially increased with increasing a G-value. This indicated that mixing (i.e., collision among particles) was very important for a coagulation reaction. Loess showed the highest RTO removal rates in the clays.

• Journal of Intelligence and Information Systems
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• 제26권4호
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• pp.87-109
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• 2020

Currently, thanks to the major stride made in developing wired and wireless communication technology, a variety of IT services are available on land. This trend is leading to an increasing demand for IT services to vessels on the water as well. And it is expected that the request for various IT services such as two-way digital data transmission, Web, APP, etc. is on the rise to the extent that they are available on land. However, while a high-speed information communication network is easily accessible on land because it is based upon a fixed infrastructure like an AP and a base station, it is not the case on the water. As a result, a radio communication network-based voice communication service is usually used at sea. To solve this problem, an additional frequency for digital data exchange was allocated, and a ship ad-hoc network (SANET) was proposed that can be utilized by using this frequency. Instead of satellite communication that costs a lot in installation and usage, SANET was developed to provide various IT services to ships based on IP in the sea. Connectivity between land base stations and ships is important in the SANET. To have this connection, a ship must be a member of the network with its IP address assigned. This paper proposes a SANET-CC protocol that allows ships to be assigned their own IP address. SANET-CC propagates several non-overlapping IP addresses through the entire network from land base stations to ships in the form of the tree. Ships allocate their own IP addresses through the exchange of simple requests and response messages with land base stations or M-ships that can allocate IP addresses. Therefore, SANET-CC can eliminate the IP collision prevention (Duplicate Address Detection) process and the process of network separation or integration caused by the movement of the ship. Various simulations were performed to verify the applicability of this protocol to SANET. The outcome of such simulations shows us the following. First, using SANET-CC, about 91% of the ships in the network were able to receive IP addresses under any circumstances. It is 6% higher than the existing studies. And it suggests that if variables are adjusted to each port's environment, it may show further improved results. Second, this work shows us that it takes all vessels an average of 10 seconds to receive IP addresses regardless of conditions. It represents a 50% decrease in time compared to the average of 20 seconds in the previous study. Also Besides, taking it into account that when existing studies were on 50 to 200 vessels, this study on 100 to 400 vessels, the efficiency can be much higher. Third, existing studies have not been able to derive optimal values according to variables. This is because it does not have a consistent pattern depending on the variable. This means that optimal variables values cannot be set for each port under diverse environments. This paper, however, shows us that the result values from the variables exhibit a consistent pattern. This is significant in that it can be applied to each port by adjusting the variable values. It was also confirmed that regardless of the number of ships, the IP allocation ratio was the most efficient at about 96 percent if the waiting time after the IP request was 75ms, and that the tree structure could maintain a stable network configuration when the number of IPs was over 30000. Fourth, this study can be used to design a network for supporting intelligent maritime control systems and services offshore, instead of satellite communication. And if LTE-M is set up, it is possible to use it for various intelligent services.