• Journal of Advanced Marine Engineering and Technology
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• v.40 no.7
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• pp.655-662
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• 2016

This study proposes that a diving supervisor, who can perform the role of both a field manager and a supervisor, be introduced in the national qualification system. The goal was achieved by surveying the general status of the commercial diving sector, including the statistics of an underwater construction company, commercial diving equipment operation condition, diver working hours, diver supply and demand status, and underwater construction market size. The national qualification and national competency standard (NCS) systems were also analyzed to deduce the role definition and work scope of the diving supervisor. Consequently, the following proposition is made: the diving supervisor should be an "on-site manager with the highest job skill in the commercial diving field, who can perform the on-site process management as well as guide, supervise, and educate project participants and serve as an intermediary between the contractor and the workers." The responsibilities of the diving supervisor are proposed to include "diving planning and operation of the diving team," "diving with surface-supplied air and mixed-gas diving system," "chamber operation," "underwater construction," and "ship salvage." The persistent issues in commercial diving sectors, such as diver career development, management, and worker supervision, are expected to be largely resolved with the introduction of this qualification.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.417-420
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• 2020

In this study, to grasp the current status of cone insects occurrence on Korean fir (Abies koreana) in Mt. Halla, 117 cones damaged by cone insects in three areas in Mt. Halla were collected and placed in growth chamber until adults emerged from the cones from August to October on 2019. And species and numbers of adults emerged from the cones were identified. Also proportion of cones damaged by cone insects was examined at four study plots in Mt. Halla. As a result, total 233, 101, and 4 adults of Dioryctria abietella (Denis & Schiffermüller), Cydia kamijoi Oku, and Scathophaga stercoraria (L.) were identified from 117 collected cones, respectively. The average number of emerged adults per cone was 1.99 for D. abietella and 0.86 for C. kamijoi. And the average damage rate of cone insects in four study plots of Mt. Halla ranged from 49.7-80.1 percent, with differences between regions. Also, our results show that positive correlation between the damage rate per tree and the number of cones per tree, and between number of emerged cone insects and the size of cones were found. It suggests that the cone insects prefer host trees with lots of cones per tree and with larger size of cones.

• Journal of IKEEE
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• v.18 no.3
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• pp.383-391
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• 2014

In this paper, temperature, pressure and flow analysis system for testing a fuel filter of a diesel engine at the low-temperature environment in winter, is proposed. The light oil of diesel engine below a specific temperature is changed to the waxing materials like paraffin, and it prevents engine to start easily because of reducing fluidity. Thus, built-in block heater should be installed with fuel filter in order to solve this problem. And it is necessary to design evaluation system that can analyze the performance according to temperature, pressure and flow characteristics near fuel filter at a very low temperature. In this paper, we measured a physical quantity related to the performance of around the fuel filter using the proposed system, and analyzed their characteristics. Also the measured data is transferred to remote user by using a web server of embedded systems, and analyzed their conditions in remote place via web browser in order to know the operating status of fuel filter. We installed the proposed system in a small test chamber to verify the performance and took an experiment in normal temperature and very low temperature, and could obtain temperature, pressure and flow of near the fuel filter. As a result, the fuel flow could be improved during operation of the fuel heater.

• Progress in Medical Physics
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• v.29 no.3
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• pp.92-100
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• 2018

The manufacturer of a linear accelerator (LINAC) has reported that the target melting phenomenon could be caused by a non-recommended output setting and the excessive use of monitor unit (MU) with intensity-modulated radiation therapy (IMRT). Due to these reasons, we observed an unexpected beam interruption during the treatment of a patient in our institution. The target status was inspected and a replacement of the target was determined. After the target replacement, the beam profile was adjusted to the machine commissioning beam data, and the absolute doses-to-water for 6 MV and 10 MV photon beams were calibrated according to American Association of Physicists in Medicine (AAPM) Task Group (TG)-51 protocol. To verify the beam data after target replacement, the beam flatness, symmetry, output factor, and percent depth dose (PDD) were measured and compared with the commissioning data. The difference between the referenced and measured data for flatness and symmetry exhibited a coincidence within 0.3% for both 6 MV and 10 MV, and the difference of the PDD at 10 cm depth ($PDD_{10}$) was also within 0.3% for both photon energies. Also, patient-specific quality assurances (QAs) were performed with gamma analysis using a 2-D diode and ion chamber array detector for eight patients. The average gamma passing rates for all patients for the relative dose distribution was $99.1%{\pm}1.0%$, and those for absolute dose distribution was $97.2%{\pm}2.7%$, which means the gamma analysis results were all clinically acceptable. In this study, we recommend that the beam characteristics, such as beam profile, depth dose, and output factors, should be examined. Further, patient-specific QAs should be performed to verify the changes in the overall beam delivery system when a target replacement is inevitable; although it is more important to check the beam output in a daily routine.

• Korean Journal of Heritage: History & Science
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• v.54 no.4
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• pp.4-21
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• 2021

The purpose of this study is to examine the names and types of walls constructed in the late Joseon Dynasty in YeonggeonUigwe, a record of construction works of the Joseon Dynasty, and to examine the current status and name of walls constructed in the main hall and the Yeongnyeongjeon Hall of Jongmyo Shrine. The results of the study are as follows. First, the name of the wall can be divided into four types depending on the characteristics, including direction, location, shape, function, material, and complexity, and was used as a compound word in front of the wall. Second, some of the wall types related to the material were found to have differences in the timing of theypes of walls. Since the 18th century, the use of earthen walls has been reduced, and the use of wooden walls and paper walls are often used. Third, the walls of the Jongmyo Shrine were composed of a mud wall and a fireproof wall. A fireproof wall was installed in the main hall, including a pillar, while the Yeongnyeongjeon Hall was installed only between the pillar and the pillar. Fourth, the Gap Wall can be defined as the "wall constructed at the upper part of the chamber used in the construction of the building in Jongmyo." This study is meaningful in that it attempted to clarify the definition of a wall in the late Joseon Dynasty by examining the names and examples of walls used in the late Joseon Dynasty, focusing on walls that lacked research in familiarity.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.9 no.2
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• pp.153-161
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• 2019

The purpose of this study to examine the status of Korean language education, and to examine the future direction between with korean and China. The Korean language course organized by the European Union Chamber of Commerce and Industry, which selects and conducts consignment companies through annual competition every year since 2002, In order to these goals and needs, it is imperative to develop a curriculum that enhances job skills. As Korean language education, a point that is necessary to clarify terms more clearly, which 'vocational education purpose' is widely used in the term of 'business education'. With all languages education, Korean language education is not meant to teach Korean to foreigners, but it is a process by which learners can apply Korean language learned in classroom to various situations, while outside the classroom through teaching and learning. Otherwise, the curriculum in the four-year college Korean language department in China, which is lacking in acquiring the ability to achieve the Korean language education goals and social needs. Korean language education in China is one of foreign language education and it is different from foreign language education such as English education as Minor Languages education.

• Journal of Korean Living Environment System
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• v.16 no.2
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• pp.89-100
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• 2009

The present study was designed to observe the thermal dynamics of core and skin temperatures during sub-maximal treadmill exercise; to investigate the effect of regional body cooling during short rest after the treadmill exercise on the thermal dynamics. Three conditions (No cooling, Head/Hand cooling, Leg cooling) were simulated in a climatic chamber at 24±1℃ and 50±5%RH. Subjects performed two bouts of treadmill exercise at a rate of 80%HR_max followed by rest. Body cooling with a hood, long gloves, and a blanket that circulated water set at 15℃ was assigned during two bouts of rest. The results showed that (1) rectal temperature (T_re) did not show significant difference between three conditions; (2) Skin temperatures had specific features, depending on body regions. In particular, the initial fall phenomena of skin temperatures at the onset of exercise were noteworthy in the chest, thigh, calf, and finger tip. Of these, the most significant initial fall was found in finger temperature (T_fing). (3) During the period of the initial fall in skin temperatures, T_re gradually increased. (4) The magnitude of the fall of T_fing at the onset of 2^nd running was on average 4.8, 5.1 and 3.4℃ for Control, HH cooling, and Leg cooling, respectively (p<0.05). The initial drop of T_fing at the onset of running was maintained for an average of 8.1, 7.9 and 6.3 minutes for Control, HH cooling, and Leg cooling, with no significant differences. In conclusion, the initial fall phenomena at the onset of treadmill exercise reflected non-thermal factors, as opposed to internal thermal status. The magnitude of the initial fall in T_fing was affected by legs cooling. Therefore, the initial fall phenomenon should be considered when interpreting the thermal status of the shell during heavy works/exercises that assigned with intermittent regional body cooling.

• Journal of radiological science and technology
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• v.26 no.2
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• pp.37-42
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• 2003

Purpose : Computed tomographic equipment is essential for diagnosis by means of radiation. With passage of time and development of science computed tomographic was developed time and again and in future examination by means of this equipment is expected to increase. In this connection these authors measured rate of scatter ray generation at front of lead glass for patients within control room of computed tomographic equipment room and outside of entrance door for exit and entrance of patients and attempted to ind out method for minimizing exposure to scatter ray. Material and Method : From November 2001 twenty five units of computed tomographic equipments which were already installed and operation by 13 general hospitals and university hospitals in Seoul were subjected to this study. As condition of photographing those recommended by manufacturer for measuring exposure to sauter ray was use. At the time objects used DALI CT Radiation Dose Test Phantom fot Head (${\oint}16\;cm$ Plexglas) and Phantom for Stomache(${\oint}32\;cm$ Plexglas) were used. For measurement of scatter ray Reader (Radiation Monitor Controller Model 2026) and G-M Survey were used to Survey Meter of Radical Corporation, model $20{\times}5-1800$, Electrometer/Ion Chamber, S/N 21740. Spots for measurement of scatter ray included front of lead glass for patients within control room of computed tomographic equipment room which is place where most of work by gradiographic personnel are carried out and is outside of entrance door for exit and entrance of patients and their guardians and at spot 100 cm off from isocenter at the time of scanning the object. The results : Work environment within computed tomography room which was installed and under operation by each hospital showed considerable difference depending on circumstances of pertinent hospitals and status of scatter ray was as follows. 1) From isocenter of computed tomographic equipment to lead glass for patients within control room average distance was 377 cm. At that time scatter ray showed diverse distribution from spot where no presence was detected to spot where about 100 mR/week was detected. But it met requirement of weekly tolerance $2.58{\times}10^{-5}\;C/kg$(100 mR/week). 2) From isocenter of computed tomographic equipment to outside of entrance door where patients and their guardians exit and enter was 439 cm in average, At that time scatter ray showed diverse distribution from spot where almost no presence was detected to spot with different level but in most of cases it satisfied requirement of weekly tolerance of $2.58{\times}10^{-6}\;C/kg$(100 mR/week). 3) At the time of scanning object amount of scatter ray at spot with 100 cm distance from isocenter showed considerable difference depending on equipments. Conclusion : Use of computed tomographic equipment as one for generation of radiation for diagnosis is increasing daily. Compared to other general X-ray photographing field of diagnosis is very high but there is a high possibility of exposure to radiation and scatter ray. To be free from scatter ray at computed tomographic equipment room even by slight degree it is essential to secure sufficient space and more effort should be exerted for development of variety of skills to enable maximum photographic image at minimum cost.

• Korean Journal of Heritage: History & Science
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• v.44 no.3
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• pp.178-199
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• 2011

The ancient tombs found in Bokcheon-dong, Busan originate from the time between the $4^{th}$ and $5^{th}$ centuries, the period of the Three Nations. They are known as the tombs where the Vertical Plate Armour was mainly buried. In 2006, two units of the Vertical Plate Armour were additionally investigated in the tombs No.164 and No.165 which had been constructed at the end of the eastern slope near the hill of the group of ancient tombs in Bokcheon-dong. Throughout this study, the contents of the two units of the Vertical Plate Armour, whose preservation process has been completed, have been arranged, while the group of constructed ancient tombs in Bokcheon-dong from the $4^{th}$ century has been observed through the consideration of the burial pattern. The units of the Vertical Plate Armour from the tombs No.164 and No.165 can be classified as the IIa-typed armor showing the Gyeongju and Ulsan patterns, according to the attribute of the manufacturing technology. Also, they can be chronologically recorded as those from the early period of Stage II among the three stages regarding the chronological recording of the Vertical Plate Armour. While more than two units of the Vertical Plate Armour were buried in the largesized tomb on the top of the hill of the group of ancient tombs, one unit of the Vertical Plate Armour was buried in the small-sized tomb. By considering such a trend, it can be said that in the stage of burying the armor showing the Gyeongju and Ulsan patterns (I-type and IIa-type), different units of the Vertical Plate Armour were buried according to the size of the tomb. However, as the armor showing the Busan pattern (IIb-type) was settled, only one unit was buried. Meanwhile, the tombs No.164 and No.165 can be included in the wooden chamber tomb showing the Gyeongju pattern, which is a slender rectangular wooden chamber tomb with the aspect ratio of more than 1:3. However, according to the trend shown by the buried earthenware, it can be said that there seem to be common types and patterns shared with the earthenware which has been found in the area of Gimhae and is called the one showing the Geumgwan Gaya pattern. In other words, there seem to be close relationships between the subject tombs and the tomb No.3 in Gujeong-dong and the tomb No.55 in Sara-ri, Gyeongju, regarding the types of armor and tombs and the arrangement of buried artifacts. However, the buried earthenware shows a relationship with the areas of Busan and Gimhae. By considering the combined trend of the Gyeongju and Gimhae elements found in one tomb, it is possible to assume that the group of constructed ancient tombs in Bokcheon-dong used to be actively related with both areas. It has been thought that the Vertical Plate Armour used to be the exclusive property of the upper hierarchy until now, since it was buried in the large-sized tomb located on the top of the hill of the group of ancient tombs in Bokcheondong. However, as shown in case of the tombs No.164 and No.165, it has been verified that the Vertical Plate Armour was also buried in the small-sized tomb in terms of such factors as locations, sizes, the amount of buried artifacts and the qualitative aspect. Therefore, it is impossible to discuss the hierarchical characteristic of the tomb just based on the buried units of the Vertical Plate Armour. Also, it is difficult to assume that armor used to symbolize the domination of the military forces. The hierarchical characteristic of the group of constructed ancient tombs in Bokcheon-dong from the $4^{th}$ century can be verified according to the location and size of each tomb. As are sult, the re seem to be some differences regarding the buried units of the vertical plate armour. However, it would be necessary to carry out amore multilateral examination in order to find out whether the burial of the vertical plate armour could be regarded as the artifact which symbolizes the status or class of the deceased.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.3
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• pp.207-213
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• 2009

This experiment was performed to understand the relationship between uptake of Fe and Mn by plants, red pepper and tomato, and soil physico-chemical properties under different soil conditions at an environmentally controlled chamber in NAAS(National Academy of Agricultural Science) in 2008. After the dipping for 3 days, four treatments, dipping, dipping+aeration, drainage, drainage+aeration, were set up to investigate the changes in soil redox potential and moisture content. Drainage+aeration changed soil to the oxidation condition from 72 hrs of treatment, and soil moisture content was immediately reduced after treatment. Uptake of Fe and Mn of red pepper was investigated with two treatments, soil only and the mixed[soil(50%) : bed soil(35%) : bark(15%)]. Red pepper leaves taken at 30 days after treatment absorbed excessively Mn from the treatment of soil only and the mixed, and thus uptake of iron was strongly reduced. Also, uptake pattern of Fe and Mn of tomato was examined with four treatment, soil only, soil(50%) + rice straw(50%), soil(50%) + compost(50%) and soil + aeration. Contents of Fe and Mn in tomato leaves was measured at 60 days after treatment. Fe content was the greatest in soil(50%) + compost(50%) whereas Mn content was the highest in soil only. As a result of this experiment, plant growth was stronger influenced by soil moisture content than redox potential or porosity, and the oxidation status of soil was likely to promote that plant predominantly absorbed Mn from soil and thus resulted in Fe deficiency.