• Journal of Korean Society of Disaster and Security
• /
• v.11 no.2
• /
• pp.29-35
• /
• 2018

This study is an experimental comparison on the fact that the sinusoidal load, which has been used so far in the laboratory cyclic test, which is an important part of the liquefaction triggering study, is somewhat different from the phenomenon that causes the soil liquefaction during the earthquake loading. To this end, this study proposes a new type of combined sinusoidal load and compares it with experimental results to load the conventional sine wave. In the comparison, the shaking table tests were carried out and the sample in the tests was remolded with the relative density of 40%, which is a condition where liquefaction is easy to occur. Firstly, the conventional cyclic test was carried out under the condition that with the amplitude of sine wave was 0.3 g. Additionally, 3 types of tests were performed using the combination loads made up with 0.03 g sinusoidal load and 0.3g sinusoidal load. At that time, the loading time for the first sinusoidal load were changed with 5 seconds, 10 seconds, and 15 seconds. As a result, the test with the conventional sine wave and the test with the first sinusoidal loading for 5 seconds showed that the change of the pore water pressure gradually increased. But in the tests with the combined sinusoidal load which changed the first sinusoidal loading time with 10 and 15 seconds, it was found that the pore water pressure suddenly rose at a certain instant and liquefaction occurs. From the experimental comparison, it is judged that it is appropriate that the time of the first sine wave is over 10 seconds at the proposed combined load for the soil condition with relative density 40%.

• The Korean Journal of Air & Space Law and Policy
• /
• v.33 no.2
• /
• pp.367-418
• /
• 2018

Just as safety is the most important thing in aviation, safety is the most important in the operation of unmanned aircraft (RPA), and safety operation is the most important in the legal responsibility of the operator of the unmanned aircraft. In this thesis, the legal responsibility of the operator of the unmanned aircraft, focusing on the responsibility of the operator of the unmanned aircraft, was discussed in depth with the issue of insurance, which compensates for damages in the event of an accident First of all, the legal responsibility of the operator of the unmanned aircraft was reviewed for the most basic : definition, scope and qualification of the operator of the unmanned aircraft, and the liability of the operator of the Convention On International Civil Aviation, the ICAO Annex, the RPAS Manual, the Rome Convention, other major international treaties and Domestic law such as the Aviation Safety Act. The ICAO requires that unmanned aircraft be operated in such a manner as to minimize hazards to persons, property or other aircraft as a major principle of the operation of unmanned aircraft, which is ultimately equivalent to manned aircraft Considering that most accidents involving unmanned aircrafts fall to the ground, causing damage to third parties' lives or property, this thesis focused on the responsibility of operators under the international treaty, and the responsibility of third parties for air transport by Domestic Commercial Act, as well as the liability for compensation. In relation to the Rome Convention, the Rome Convention 1952 detailed the responsibilities of the operator. Although it has yet to come into effect regarding liability, some EU countries are following the limit of responsibility under the Rome Convention 2009. Korea has yet to sign any Rome Convention, but Commercial Act Part VI Carriage by Air is modeled on the Rome Convention 1978 in terms of compensation. This thesis also looked at security-related responsibilities and the responsibility for privacy infringement. which are most problematic due to the legal responsibilities of operating unmanned aircraft. Concerning insurance, this thesis looked at the trends of mandatory aviation insurance coverage around the world and the corresponding regulatory status of major countries to see the applicability of unmanned aircraft. It also looked at the current clauses of the Domestic Aviation Business Act that make insurance mandatory, and the ultra-light flight equipment insurance policy and problems. In sum, the operator of an unmanned aircraft will be legally responsible for operating the unmanned aircraft safely so that it does not pose a risk to people, property or other aircraft, and there will be adequate compensation in the event of an accident, and legal systems such as insurance systems should be prepared to do so.

• Journal of Korean Society of Disaster and Security
• /
• v.14 no.2
• /
• pp.61-75
• /
• 2021

Recently, as the occurrence frequency of sudden floods due to climate change increased and the aging of the existing spillway, it is necessary to establish a plan to utilize an auxiliary spillway to minimize the flood damage of downstream rivers. Most studies have been conducted on the review of flow characteristics according to the operation of auxiliary spillway through the hydraulic experiments and numerical modeling. However, the studies on examination of flood damage in the downstream rivers and the stability of the revetment according to the operation of the auxiliary spillway were relatively insufficient in the literature. In this study, the stability of the revetment on the downstream river according to the outflow conditions of the existing and auxiliary spillway was examined by using 3D numerical model, FLOW-3D. The velocity, water surface elevation and shear stress results of FLOW-3D were compared with the permissible velocity and shear stress of design criteria. It was assumed the sluice gate was fully opened. As a result of numerical simulations of various auxiliary spillway operations during flood season, the single operation of the auxiliary spillway showed the reduction effect of maximum velocity and the water surface elevation compared with the single operation of the existing spillway. The stability of the revetment on downstream was satisfied under the condition of outflow less than 45% of the design flood discharge. However, the potential overtopping damage was confirmed in the case of exceeding the 45% of the design flood discharge. Therefore, the simultaneous operation with the existing spillway was important to ensure the stability on design flood discharge condition. As a result of examining the allocation ratio and the total allowable outflow, the reduction effect of maximum velocity was confirmed on the condition, where the amount of outflow on auxiliary spillway was more than that on existing spillway. It is because the flow of downstream rivers was concentrated in the center due to the outflow of existing spillway. The permissible velocity and shear stress were satisfied under the condition of less than 77% of the design flood discharge with simultaneous operation. It was found that the flood damage of downstream rivers can be minimized by setting the amount allocated to the auxiliary spillway to be larger than the amount allocated to the existing spillway for the total outflow with simultaneous operation condition. However, this study only reviewed the flow characteristics around the revetment according to the outflow of spillway under the full opening of the sluice gate condition. Therefore, the various sluice opening conditions and outflow scenarios will be asked to derive more efficient utilization of the auxiliary spillway in th future.

• Journal of the Korean Society of Radiology
• /
• v.16 no.4
• /
• pp.477-490
• /
• 2022

Serious Accident Punishment Act(SAPA) went into effect as of Jan. 27, 2022. The subject of study was the worker of the nuclear medicine department and the investigation was aimed at identifying the present situation of their understanding on the issue in the here and now, which can be utilized as basic research for further study. The survey was conducted on 51 people of the worker in the nuclear medicine department. The general factors were classified by their gender, the scale of the hospitals, the period of career, and the detailed occupational categories. The conclusion was drawn, including 1 missing data in gender and 2 in the type of occupation. The targeted hospitals were tertiary hospital, university hospital, and general hospital which have nuclear medicine department in. The period of subjects' career was categorized by less than 3 years, 3 to 5 years, 5 to 10 years, and more than 10 years. The specific occupation was classified by in-vivo radiological technologist, radiation safety manager and others. The amount of pressure that the job entails was highest in the category of general hospital, the period of 3 to 5 years of job experience, and radiation safety manager each. The system of the code was well constructed in the category of general hospital, the period of less than 3-year career, and radiation safety manager, as they responded. The blood transmissible disease had the largest number of outbreak of accidents related to the serious industrial accident. In addition, the radiopharmaceutical dosing error had the highest number of outbreak of accidents related to the serious civil accident. Therefore, we need to improve SAPA, facility inspection, security of budget, security of professional manpower. It will help the stable use of radiation and ensure patient safety.

• Journal of Korean Society of Disaster and Security
• /
• v.16 no.2
• /
• pp.15-32
• /
• 2023

There are some difficulties such as safety problem and need of manpower in measuring discharge by submerging the instruments because of many floating debris and very fast flow in the river during the flood season. As an alternative, microwave water surface current meters have been increasingly used these days, which are easy to measure the discharge in the field without contacting the water surface directly. But it is also hard to apply the method in the sudden and rapidly changing field conditions. Therefore, the estimation of the discharge using the surface velocity in flood conditions requires a theoretical and economical approach. In this study, the measurements from microwave water surface current meter and rating curve were collected and then analyzed by the discharge estimation method using the surface velocity. Generally, the measured and converted discharge are analyzed to be similar in all methods at a hydraulic radius of 3 m or over or a mean velocity of 2 ㎧ or more. Besides, the study computed the discharge by the index velocity method and the velocity profile method with the maximum surface velocity in the section where the maximum velocity occurs at the high water level range of the rating curve among the target locations. As a result, the mean relative error with the converted discharge was within 10%. That is, in flood season, the discharge estimation method using one maximum surface velocity measurement, index velocity method, and velocity profile method can be applied to develop high-level extrapolation, therefore, it is judged that the reliability for the range of extrapolation estimation could be improved. Therefore, the discharge estimation method using the surface velocity is expected to become a fast and efficient discharge measurement method during the flood season.

• Korean Journal of Social Welfare
• /
• v.36
• /
• pp.39-69
• /
• 1998

The study is to grope for the unified device of the women's welfare policy in the United Korea by considering and comparing with the women's welfare in South Korea and North Korea centering on the women's welfare law and system among the social security laws and systems in the present both countries. The both Koreas have enforced the different women's welfare policies according to the different ideologies and constitutions. But in the welfare policy women are in the secondary stage by means of the ideology of sexual devision. It, therefore, is clear that the position of the North Korean woman goes in advance of the South Korean woman in the law and system. However, they are similar to the North Korean women in the aspects of the application of law and system. That is, both of them are discriminated not only in home and labor participation, but also in social welfare. There are the patriarchal family system and sexual devision of labor under the discrimination against woman. As though the both sexes are equal in law, the welfare law and system are applicated unequally to woman because of the ideology of sexual devision and familism which family should take the primary responsibility of welfare. From this perspective the women's welfare policy of the United Korea is not just to unify both laws and systems related women's welfare, but to search for the convergence on the higher level of quality and to make the real gender-equal society. The study suggests as the women's welfare the spread of the application of social welfare system, and social security network constructed through the mother protection policy, women's poverty and social security on basis of the primary principles such as the gender equal right as civil right, benefits of social welfare as social right, escape from the patriarchal familism, strengthening of resposibility of state and the principle of women participation in process of social welfare management. The device of women's welfare means building the social welfare system based on the real gender equality, so the unification will be the important turning point for the gender-equal society to the South-North Korean women.

• Korean Security Journal
• /
• no.28
• /
• pp.33-56
• /
• 2011

This study is to practice a analysis of Q-methodological preference degree about the subjects on school curriculum centering around the views of the policemen in active service who are with Gwang Ju and Jeon Nam region. Concretely, this study mixed the subjects on school curriculum related to the police administration of universities located in Gwang Ju and Jeon Nam region and abstracted the twenty seven items as the final question point. Above this, this study integrated the similar or repeated subjects and drew up the question items through seperation process among the different subjects. After this, this study selected the twenty policemen as a first P-sample in active service presently on fourth month in the year 2011. In this process, this study eliminated the materials of six policemen who replyed unhonestly and selected the materials of ten-four policemen as a final effective sample. Furthermore, this study applicated a principal component analysis. This study practiced the I.II.III types of a preference degree analysis of the subjects related to the police administration. the concrete results are as follows: In a I type, the positive consent was showed in the subjects of criminal law, criminal procedure law, criminal speciality law and so on. In a II type, the positive consent was showed in criminal investigation science, emergency measure, the art of self-defence, criminal law, criminal procedure law and so on. In a III type, the positive consent was showed in criminal science, criminal investigation science, criminal procedure law, introduction to police science, police ethics and so on. On this basis, this study concluded the following common opinions. Firstly the actual and evidencial subjects which the policemen in active service feel as the commons were criminal investigation, criminal science, police ethics, criminal speciality law, criminal law business, police administration science, police law practice, emergency measure, the art of self-defence, general rules of civil law, administrative law and so on.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.15 no.3
• /
• pp.60-67
• /
• 2016

In cumulative transfer functions, as number of transfer increase, the impact of individual transfer to transfer cost increase linearly or non linearly. This function can effectively explain various passengers's travel behavior who choose their travel routes in integrated transit line networks including bus and railway modes. Using the function, it is possible to simulate general situations such that even though more travel times are expected, less number of transfer routes are preferred. However, because travel cost with cumulative transfer function is known as non additive cost function types in route search algorithms, finding an optimal route in integrated transit networks is confronted by the insolvable enumeration of all routes in many cases. This research proposes a methodology for finding an optimal path considering cumulative transfer function. For this purpose, the reversal phenomenon of optimal path generated in route search process is explained. Also a heuristic methodology for selecting an optimal route among multiple routes predefined by the K path algorithm. The incoming link based entire path deletion method is adopted for finding K ranking path thanks to the merit of security of route optimality condition. Through case studies the proposed methodology is discussed in terms of the applicability of real situations.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.37 no.6
• /
• pp.563-570
• /
• 2019

Red tide has caused massive fish kills in Korean coastal waters with devastating economic loss in the aquaculture industry since 1995. Remote sensing technique has shown to be effective for the detection of red tide in wide areas, where the absorption property of red tide water plays a central role in understanding the red tide reflectance. This study analyzed the optical absorption property of sea waters dominated by the dinoflagellate specie of Alexandirum affine, off the Tongyeong area in August, 2017. Water samples collected from 20 stations in the ship-based campaign were measured for absorption by pigment, suspended solid, and dissolved organic matter, with the corresponding water quality variables such as chlorophyll concentration and total suspended solid. The analysis showed that Alexandrium-dominated water exhibits strong absorption in the spectral range below 400 nm unlike that of diatom-dominated waters, and greater fluctuations in the range of 400 nm - 500 nm. The packaging effect in pigment absorption was stronger in Alexandrium-dominated waters, and the exponent in the absorption by detritus and gelbstoff is disparate for diatom and Alexandrium. In the model for the detritus and gelbstoff absorption (a_dg(λ)=a_dg(λ₀)e^-s(λ-λ₀)), the optimal exponent coefficient(s) for the Alexandrium was close to 0.01 rather than to 0.015, which was commonly use for modelling diatom waters.

• The Journal of the Korea Contents Association
• /
• v.14 no.8
• /
• pp.466-475
• /
• 2014

According to the Housing Lease Protection Act, even though it is not registered, if the lessee has completed delivery of a house and the resident registration, the lease shall take effect against the third person from the following day thereof. Any lessee who has met the requirements for opposing power and obtained the fixed date on the lease contract document, shall be entitled to receive the repayment of the deposit from the converted price of the leased house, in preference to any junior obligors and other creditors, at the time of an auction as provided by the Civil Execution Act and a public sale as prescribed by the National Tax Collection Act. The lessee shall be entitled to receive a repayment of a specified amount of the deposit in preference to other persons having the security rights in the leased house. However those provisions give rise to many problems because the Housing Lease Protection Act allows the opposing power and the right of preferential payment from the following date of fulfillment of the requirement. For the purpose of solving the problems, this study suggests that the Housing Lease Protection Act need to be amended as follows. The fixed date should be added to the requirement of opposing power and the preferential right of specified deposit repayment. In addition, the commencement of opposing power and preferential right of deposit repayment need to be taken effect from the day that the requirement is fulfilled.