• Fire Science and Engineering
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• v.25 no.6
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• pp.136-145
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• 2011

One of a large proportion among the causes of fire is electrical factors, and of fire by electric factors, the accident which accounted for over certain percentage is electric leakage and ground fault. In order to reduce the electric leakage and ground fault, the technical guidelines on the protection of ground fault in the low-voltage electrical line (KECG 1091-2011) was amended for reflecting recent international standard, IEC 60364-4-41, and new conservation methods, which improved the reliability by recovering the facility's all-time use operation and breakdown defect, was on the rise. Accordingly, in this paper, after grasping the fire's status for last 10 years and analyzing the risk of electrical fires, and as a way to improve the electric leakage and ground fault accident which accounted for more than certain percentage, the revision of KECG 1091-2011 will be reviewed. And then, after applying to the preventive conservation methods in order to enhance the protection reliability of electric leakage and ground fault detection, the problems at issue routine inspection scheme and durable years scheme in time-scheduled conservation method are listed, along with suggestion of the problem-solving scheme, and the leakage current integrated monitoring systems and digital electric leakage devices by status monitor conservation method will be proposed.

• The Journal of the Korea Contents Association
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• v.13 no.4
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• pp.170-186
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• 2013

As the population is getting older, medical expenses amount of the whole is keep increasing. So, the pressure of the finances, Health Insurance, Medical Care Assistance Act and etc, is getting higher. The share of healthcare-expense is increasing due to elderly illness. And it became a social problem; we analysed present state of senior healthcare in South Korea-looked into current laws and policies, and found problems. We tried to suggest improvements that drew from the current state of foreign country senior healthcare of those problems. For the result, we found the problem in relevant-law system of senior healthcare guarantee. In this study, we proposed the ways to qualitatively upgrade of medical standard that considered on elderly' features: the strengthened guarantee for healthcare, financial secure for long-term convalescence benefit, linking and functional reinforcement for elderly welfare and long-term convalescence insurance, the solution for overlapped laws about convalescence in long-term convalescence insurance and elderly welfare, a betterment of grading, and a home service consolidation. We need to secure right amount of emergency medical service budget, and effective management system for the improved level of senior severely emergency medical service. Furthermore, we suggested that South Korea needs to legislate [The Law for Senior Medical Secure] to respond to rapidly increasing senior healthcare fee.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.1
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• pp.1-7
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• 1985

Various types of shearing devices which may be a substitute for the conventional beams in stow nets were considered, and then tentatively named "the zonal canvas type of stow net" having the shearing device made of zonal canvas was devised. A 1/3 model of the net was made and experimented at sea. Converted to the full scale, the measured water resistance R(kg) of the net was given by $R=5.6{\times}10^{3}V^{l.5}$ or $R=3.5\frac{d}{l}{\lambda}_b{\lambda}_l\;V^{1.5}$, where V is the water velocity (m/sec), d the diameter of netting bars, l the length of the bars, ${\lambda}_b$ the stretched circumference of net mouth (m), ${\lambda}_l$ the length of net stretched. The net height kept about $83\%$ of the side rope length regardless of the variation of V and the net breadth kept a value over $90\%$ of the head rope length until V reached 1 m/sec. These results were very successful according to expectation, but the conventional netting was requested a further improvement. Therefore, the netting was newly designed to have smaller size of meshes in the vicinity of net mouth and larger hanging ratio breadthwise. With the netting a full scale net was made and experimented by a stern trawler. The experiment gave a net breadth over $95\%$ of the head rope length until V reached 1m/sec and showed no faults in the net. But the net operation by the stern trawler was ascribed an inconvenience to its narrow breadth of stern slip way.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.5
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• pp.29-39
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• 2020

Some drivers cannot meet the standards for a full driver's license and many countries allow them to drive a vehicle as long as they can satisfy certain conditions. Korea has mainly issued conditional driver's licenses to the disabled only after supplementary devices are attached either in the vehicle or in their bodies. However, it is becoming important to issue a conditional driver's license to other types of drivers, including the elderly as the population ages in the country. This study aims at improving the current practice of issuing conditional driver's licenses by benchmarking various types of conditional licenses in other countries. In particular, various conditions such as time, space, driving speed, road type, vehicle type, and specific individual conditions are compared. Issuing a conditional driver's license to various types of drivers should be beneficial, not only to elderly drivers but also to drivers who cannot live without a vehicle.

• JSTS:Journal of Semiconductor Technology and Science
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• v.7 no.3
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• pp.196-208
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• 2007

An analytical model is proposed for an optically controlled Metal Semiconductor Field Effect Transistor (MESFET), known as Optical Field Effect Transistor (OPFET) considering the diffusion fabrication process. The electrical parameters such as threshold voltage, drain-source current, gate capacitances and switching response have been determined for the dark and various illuminated conditions. The Photovoltaic effect due to photogenerated carriers under illumination is shown to modulate the channel cross-section, which in turn significantly changes the threshold voltage, drainsource current, the gate capacitances and the device switching speed. The threshold voltage $V_T$ is reduced under optical illumination condition, which leads the device to change the device property from enhancement mode to depletion mode depending on photon impurity flux density. The resulting I-V characteristics show that the drain-source current IDS for different gate-source voltage $V_{gs}$ is significantly increased with optical illumination for photon flux densities of ${\Phi}=10^{15}\;and\;10^{17}/cm^2s$ compared to the dark condition. Further more, the drain-source current as a function of drain-source voltage $V_{DS}$ is evaluated to find the I-V characteristics for various pinch-off voltages $V_P$ for optimization of impurity flux density $Q_{Diff}$ by diffusion process. The resulting I-V characteristics also show that the diffusion process introduces less process-induced damage compared to ion implantation, which suffers from current reduction due to a large number of defects introduced by the ion implantation process. Further the results show significant increase in gate-source capacitance $C_{gs}$ and gate-drain capacitance $C_{gd}$ for optical illuminations, where the photo-induced voltage has a significant role on gate capacitances. The switching time ${\tau}$ of the OPFET device is computed for dark and illumination conditions. The switching time ${\tau}$ is greatly reduced by optical illumination and is also a function of device active layer thickness and corresponding impurity flux density $Q_{Diff}$. Thus it is shown that the diffusion process shows great potential for improvement of optoelectronic devices in quantum efficiency and other performance areas.

• The Journal of Korean society of community based occupational therapy
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• v.5 no.2
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• pp.31-42
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• 2015

Objective : The aim of this study is to prove the effects of mental practice in balance ability of elderly population, and to investigate the possibility of application as an effective intervention method for fall prevention. Methods : This study provided mental practice to 3 subjects over 65 years old who have experienced fall, but do not have cognitive dysfunctions and independent in gait without any use of assistive devices from July to October, 2013. Within the individual case study, 4 sessions of initial baseline process (A), 5 sessions of mental practice (B), 4 sessions of re-initial baseline process (A') were proceeded using ABA design. Independent variable used mental practice for enhancing balance ability and fall efficacy in elderly population, and dependent variable were Berg Balance Scale (BBS) to find out the change in overall balance ability, Fall Efficacy Scale (FES) to see the change in fall efficacy, One-Leg Standing test(OLS), and Timed Up and Go Test (TUG) to determine the changes in both static and dynamic balance. Analysis of the results were provided via mean value and graph. Results : After the application of mental practice method, all of the subjects have shown increase in fall efficacy baseline values, and in addition, overall balance ability and both static and dynamic balances either increased or maintained. Conclusion : This study demonstrated that mental practice has positive effects on fall efficacy improvement and maintenance in elderly, thereby suggesting mental practice for fall prevention in elderly populations.

• Journal of Navigation and Port Research
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• v.41 no.4
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• pp.215-228
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• 2017

Taking a look at recent trends of port cities, many port cities in the world have been shedding new light on the function being kept by existing port spaces, caused by changes of industrial structure according to the stream of the times, developments of surrounding areas, and etc., and we can see that its meaning also has been changing. However, in case of domestic port spaces they are in the real situation not responding to those movements quickly. Therefore, unlike the existing zoning system dividing functionally urban spaces according to use simply, in this study FBCs getting the timelight recently as a system capable of reflecting spatial characteristics at the maximum have been utilized as a measure for solving current problems of urban spaces. The purpose of this study is to propose the direction of urban planning approach that harmonizes the whole harbor space by strengthening the interlinkage between heterogeneous spaces of port area and port area using FBCs. FBCs are institutional devices that are proposed and implemented in the United States to reflect the unique characteristics of the space, that is, the location and the uniqueness, and the pedestrian-oriented space planning.

• The Journal of Sustainable Design and Educational Environment Research
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• v.19 no.2
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• pp.1-10
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• 2020

Despite the legal and institutional measures that have been enacted for the safety management of school facilities, the number of school accidents has continued to rise, particularly in regards to the number of accidents related to schools. However, school facilities have had a difficult time creating safe school environments for the school administration and local governments. This is due to the fact that the Office of Education and the Ministry of Education, not the school or educational offices, have insufficient institutional devices such as standards and systems for the promotion of safe school environments. This study attempted to confirm the direction of the improvement of the safety of school facilities. To this end, four safety assessment topics (separation of pedestrians, pedestrian path management, pedestrian visibility, and surrounding risk factors) were derived based on the surveyed data for the safety of the external environment of domestic and international school facilities. 179 school facilities nationwide (kindergartens, elementary schools, middle schools, high schools, and special schools) were analyzed for current cases of accidents that occurred mainly on school roads. Roughly 50% of the analyzed evaluation scores showed that it is necessary to improve the external environment of school facilities.

• Journal of The Korean Association For Science Education
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• v.30 no.6
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• pp.785-798
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• 2010

The purposes of this study are to investigate Korean science teachers' perception of the current science teacher preparation courses in Korea, especially focused on subjects of science education, and to induce implications for improvement of in-service program for science teachers. To do this, a questionnaire was developed by the authors and administered to the 215 science teachers sampled nationwide. The study concluded that science teachers perceived that the two compulsory subjects, 'science education theories' and 'science teaching-learning materials and teaching methods' were not enough for a professional science teacher. Particularly, they consisently insisted that more practices under the relationship with teaching science in schools were necessary when learning subjects of science education. Based on science teachers' response, we recommended that the following 4 subjects should be added in the course of pre-service program for science teachers: 'Development of experiment/demonstration devices', 'Teaching creativity and education for the gifted in science', 'Development of science teaching materials', and 'Science inquiry learning and teaching'.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.2
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• pp.208-215
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• 2017

When persistent oil, such as crude oil or Bunker C oil, is spilled at sea, viscosity increases through the weathering process. Equipment that can collect this oil when mixed with floating marine debris is very limited. In this study, devices that can be attached to the outside of existing oil skimmers have been applied to the inside of the main body, to develop an unmanned conveyor belt type floating marine debris and high viscosity oil recovery skimmer, which is composed of a conveyor belt, a sweeper with a forced inflow device, and a collection tank equipped with a buoyant body. The resulting skimmer was operated at a speed of 1.2 knots at a distance of 30 m in a sea area test. It was stable when moving laterally in any direction. An oil recovery performance test was conducted using a portable storage tank, and oil was recovered from a minimum of $7.8k{\ell}/h$ to a maximum of $23.3k{\ell}/h$. Moreover, recovery of $7.7k{\ell}/h$ was obtained in a wave water tank test with floating marine debris such as PET bottles and oil mixed. If the equipment developed in this study was used in the field for oil pollution accidents, it could be expected to contribute to improved response capability. We believe our equipment could be used in further studies to improvement the performance of existing portable oil skimmers.