• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.3
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• pp.189-195
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• 2017

The only method used in the power stations in order to deliver generated electric power is 6 kV XLPE (or CV) single core cables. Among many kinds of accidents happening in the power stations, the outbreak of fire due to the deterioration of live cables causes enormous socioeconomic losses. From the installation of the cables, the management and diagnose should be thoroughly made. Even though it differs depending on the installations and usage conditions, the cross-sectional area of cables is in shortage. The excessive allowable temperature caused from the current causes the deterioration of cables. In order to prevent an unexpected breakdown of live cables, we have invented a device to monitor and diagnose the status of cables. We have installed our device in the Korea Western Power Co., Ltd.. In this paper, we present our research results in situ that we have obtained by measuring the temperature of sheath, changing with the surrounding circumstances, especially ambient temperatures. We also show our study results of characteristics for temperature of sheath surface and load current at the ambient temperatures of $40^{\circ}C-10^{\circ}C$.

• Journal of Technologic Dentistry
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• v.34 no.4
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• pp.447-455
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• 2012

Purpose: This study was to investigate oral hygiene knowledge and the actual condition of oral care for the students in the public health and non-public health Departments. Methods: The survey sample consisted of 262 randomly selected students. 197 of them are public health-related students and 65 are non-public health-related students. The questionnaires used in this study consisted of 4 items for general information, oral health status of 2 items, 5 items for Oral hygiene knowledge and actual condition of oral care of 5 items. Collected data were analyzed by Frequency Analysis t-test and Crosstabs using SPSS(Statistical Package for Social Sciences) Win 19.0 statistics program. Results: Regarding general characteristics of the subjects, there were 53.8% of first-year student, 26.0% of second-year student and 20.2% of third-year student among 52.3% of males and 47.7% of females. The subjects received less than "100,000" won(13.0%), "100,000-190,000" won (5.0%), "200,000-290,000" won(30.9%), "300,000-390,000" won (33.2%) and more than "400,000" won(17.9%) a month for an allowance. The subjects had 'none' (44.3%), '1'(6.5%), '2'(12.6%), '3'(5.0%), '4'(5.3%), 'more than' 5(0.8%) of dental caries and 'do not know' were 25.6%. The numbers of dental prosthetics were 'no' (35.5%), '1'(13.7%), '2'(17.2%), '3'(10.3%), '4'(11.5%), and 'more than 5'(11.8%). The public health students(84.8%) had a higher positive response rate than the non-public health students(66.2%). The public health students(80.2%) had a higher negative response rate than the non-public health students(78.5%) in the result of onset of gum disease pain awareness. The non-public health students(65.5%) had a higher negative response rate than the public health students(68.3%)) in the result of heredity of gum disease. The t-test showed that public health-related department students(M=8.264, SD=0.821) had more knowledge about oral hygiene than non-public health-related department students(M=8.015, SD=1.082). 'do not use' in the oral care products except toothpaste and toothbrush showed that public health-related department students(60.4%) use the products more than non-public health-related department students(66.2%). Conclusion: In this study, public health-related department students had higher oral hygiene knowledge and actual condition of oral care compared to non-public health-related students, but low in practical action. Due to the lower level of dental care products use in non-public health-related department, a continuous oral care education program is required.

• Journal of Radiation Protection and Research
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• v.45 no.2
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• pp.76-80
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• 2020

Background: To improve the measurement accuracy of liquid-scintillation counting for activity standardization, it is necessary to significantly reduce the background caused by thermal noise or after-pulses. We have therefore improved a movable 3 photomultiplier (3PM)-γ coincidence-counting method using the logical sum of three double coincidences for β events. Materials and Methods: We designed a new data-acquisition system in which β events are obtained by counting the logical sum of three double coincidences. The change in β-detection efficiency can be derived by moving three photomultiplier tubes sequentially from the liquid-scintillation vial. The validity of the method was investigated by activity measurement of ¹³⁴Cs calibrated at the Korea Research Institute of Standards and Science (KRISS) with 4π(PC)β-γ(NaI(Tl)) coincidence counting using a proportional counter (PC) for the β detector. Results and Discussion: Measurements were taken over 14 counting intervals for each liquidscintillation sample by displacing three photomultiplier tubes up to 45 mm from the sample. The dead time in each β- and γ-counting channel was adjusted to be a non-extending type of 20 ㎲. The background ranged about 1.2-3.3 s^-1, such that the contributions of thermal noise or after-pulses were negligible. As the β-detection unit was moved away from the sample, the β-detection efficiencies varied between 0.54 and 0.81. The result obtained by the method at the reference date was 396.3 ± 1.7 kBq/g. This is consistent with the KRISS-certified value of 396.0 ± 2.0 kBq/g within the uncertainty range. Conclusion: The movable 3PM-γ method developed in the present work not only succeeded in reducing background counts to negligible levels but enabled β-detection efficiency to be varied by a geometrical method to apply the efficiency extrapolation method. Compared with our earlier work shown in the study of Hwang et al. [2], the measurement accuracy has much improved. Consequently, the method developed in this study is an improved method suitable for activity standardization of β-γ emitters.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.3243-3254
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• 2013

It is well known that increased incidences of lung, skin, and bladder cancers are associated with occupational exposure to PAHs. Animal studies show that certain PAHs also can affect the hematopoietic and immune systems and can produce reproductive, neurologic, and developmental effects. As a consequence, several studies have been attempted to investigate the fate of PAHs in atmospheric environment during the past decades. However, there is still a lack of information in regard to the atmospheric concentration of PAHs during the "Bon Fire Night". In this study, twenty-three polycyclic aromatic hydrocarbons and twenty-eight aliphatics were identified and quantified in the $PM_{10}$ and vapour range in Birmingham ($27^{th}$ November 2001-$19^{th}$ January 2004). The measured concentrations of total particulate and vapour (P+V) PAHs were consistently higher at the BROS in both winter and summer. Arithmetic mean total (P+V) PAH concentrations were $51.04{\pm}47.62$ ng $m^{-3}$ and $22.30{\pm}19.18$ ng $m^{-3}$ at the Bristol Road Observatory Site (BROS) and Elms Road Observatory Site (EROS) respectively. In addition arithmetic mean total (P+V) B[a]P concentrations at the BROS were $0.47{\pm}0.39$ ng $m^{-3}$ which exceeded the EPAQS air quality standard of 0.25 ng $m^{-3}$. On the other hand, the arithmetic mean total (P+V) aliphatics were $81.80{\pm}69.58$ ng $m^{-3}$ and $48.00{\pm}35.38$ ng $m^{-3}$ at the BROS and EROS in that order. The lowest average of CPI and $C_{max}$ measured at the BROS supports the idea of traffic emissions being a principle source of SVOCs in an urban atmosphere. The annual trend of PAHs was investigated by using an independent t-test and oneway independent ANOVA analysis. Generally, there is no evidence of a significant decline of heavier MW PAHs from the two data sets, with only Ac, Fl, Ph, An, 2-MePh, 1+9-MePh, Fluo and B[b+j+k]F showing a statistically significant decline (p<0.05). A further attempt for statistical analysis had been conducted by dividing the data set into three groups (i.e. 2000, 2001-2002 and 2003-2004). For lighter MW compounds a significant level of decline was observed by using one-way independent ANOVA analysis. Since the annual mean of $O_3$ measured in Birmingham City Centre from 2001 to 2004 increased significantly (p<0.05), it may be possible to attribute the annul reduction of more volatile PAHs to the enhanced level of annual average $O_3$. By contrast, the heavier MW PAHs measured at the BROS did not show any significant annual reduction, implying the difficulties of 5- and 6-ring PAHs to be subject to photochemical decomposition. The deviation of SVOCs profile measured at the EROS was visually confirmed during the "Bonfire Night" festival closest to the $6^{th}$ November 2003. In this study, the atmospheric PAH concentrations were generally elevated on this day with concentrations of Fl, Ac, B[a]A, B[b+j+k]F, Ind and B[g,h,i]P being particularly high.

• Asian Journal of Atmospheric Environment
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• v.6 no.4
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• pp.281-287
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• 2012

Aerosol concentrations at the CC-Lag site in the Teshio Experimental Forest increased from winter to spring and sometimes showed extremely high values associated with Kosa and/or forest-fire events. The range and mean of the mass concentrations of aerosol chemical species were as follows: total particulate mass, 1.2-29, 5.0; elemental carbon, 0.061-2.2, 0.43; organic carbon, 0.059-3.5, 0.79; and sulfate, 0.12-6.2, 1.8 ${\mu}g/m^3$. The total masses of the deposited particles on hybrid larch and on bamboo leaves were approximately 35 and 30 ${\mu}g/cm^2$, respectively. The amounts of soil particles on the leaves were 6 ${\mu}g/cm^2$ for the upper part of hybrid larch, 2 ${\mu}g/cm^2$ for the lower part of hybrid larch, and 1 ${\mu}g/cm^2$ for Sasa bamboo leaves. The amounts of deposited black carbon were 2.3 ${\mu}g/cm^2$ for the upper part of hybrid larch, 0.6 ${\mu}g/cm^2$ for the lower part of hybrid larch, and 0.2 ${\mu}g/cm^2$ for Sasa bamboo leaves. Half of the total deposited particular mass was attached on the hybrid larch; however, most of the total deposited mass was adhered on the Sasa bamboo leaves. Regardless of the species, there tend to be more deposited particles on the leaves in the upper part than in the lower part, with only a few meters height difference. Comparing the composition of the deposited particles to that of the atmospheric aerosols without any size cut, the fractions of water-soluble material sulfate and sea salt in the deposited aerosols were about one tenth and one hundredth lower than that in the aerosols, respectively. On the basis of the measured concentration and the deposited amount on leaves, the deposition velocity of black carbon was estimated to be approximately 0.5 cm/s.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.500-506
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• 2018

This study analyzed current prehospital emergency care for severe trauma patients administered by different number of 119 EMS (emergency medical services) teams. Out of 1,067 severe trauma patients transferred by 119 EMS teams in J province from January 1st to December 31st 2015, 438 were evaluated in this study. IBM SPSS Statistics 21.0 was used to analyze collected data. The number of patients with severe trauma during the period of study was higher in male with two and three ambulance crews of 119 EMS teams with 242 patients (70.6%) and 66 patients (69.5%) respectively. The percentage of transfers made to local emergency medical centers was highest in those two groups, being 44.0% (151 patients) and 49.5% (47 patients), respectively. Total time spent at the scene did not differ between ambulance crews of two and three, nor did the frequency of practicing advanced airway management and IV (intravenous) cannulation, or the success rate of IV cannulation (p=0.253, p=0.362, p=1.000). Overall, the results indicated that merely increasing the number of paramedics does not improve the quality of prehospital care for severe trauma patients. Measures such as securing professional paramedics, simplifying direct medical oversights, activating indirect medical oversights, and expanding the legally allowed work scope are required.

• Journal of Korean Society of Forest Science
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• v.83 no.3
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• pp.322-330
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• 1994

The Universal Soil Loss Equation (USLE) has been widely used to predict long-term soil loss by incorporating several erosion factors, such as rainfall, soil, topography, and vegetation. This study is aimed to introduce the LISLE within geographic information system(GIS) environment. The Kwangneung Experimental Forest located in Kyongki Province was selected for the study area. Initially, twelve years of hourly rainfall records that were collected from 1982 to 1993 were processed to obtain the rainfall factor(R) value for the LISLE calculation. Soil survey map and topographic map of the study area were digitized and subsequent input values(K, L, S factors) were derived. The cover type and management factor (C) values were obtained from the classification of Landsat Thematic Mapper(CM) satellite imagery. All these input values were geographically registered over a common map coordinate with $25{\times}25m^2$ ground resolution. The USLE was calculated for every grid location by selecting necessary input values from the digital base maps. Once the LISLE was calculated, the resultant soil loss values(A) were represented by both numerical values and map format. Using GIS to run the LISLE, it is possible to pent out the exact locations where soil loss potential is high. In addition, this approach can be a very effective tool to monitor possible soil loss hazard under the situations of forest changes, such as conversion of forest lands to other uses, forest road construction, timber harvesting, and forest damages caused by fire, insect, and diseases.

• Journal of Navigation and Port Research
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• v.29 no.1 s.97
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• pp.35-42
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• 2005

This study aims at analyzing the extent of seafarers' perception on their stress and ways to cope with the stress and providing fundamental data for establishing on the stress management of seafarers. In this paper 428 seafarers, who were in the fire-fighting and survival technique training course in Korea Institute of Maritime and fisheries Technology, were sampled and asked to fill out two kinds of questionnaire. One is a questionnaire on seafarers' stress perception and the other is that on the measure of their coping with stress. The collected data were analyzed by using descriptive statistics, t-test and ANOVA by SPSS 10.1 package. The results of this study are as follow. 1) There were significant differences of stress perception in navigation area, marital status, amount of smoking, frequency of drinking, exercise, sleep pattern, sleeping hours, leisure time, and job satisfaction 2) There were significant differences of method coping with stress in current position, navigation area, age, ship career, level of education, marital status, yearly income, frequency of drinking, amount of drinking, exercise, sleep pattern, and job satisfaction 3) The relation between stress perception and ways of coping with stress showed that the group with higher stress perception tended to use emotion-focused coping style and desirable thinking.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.4
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• pp.94-104
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• 2014

This contribution studied knowledges, informations and main project issues for systematic conservation management utilize of Joseon Royal Tombs guaranteeing their Outstanding Universal Value, Authenticity and Integrity, and the outcomes are as follows. The first, regarding the tomb's system, it should be planned to enhance authenticity and integrity of Joseon Royal Tombs through historical facts, measurement, diagnosis and intervention according to international and national charters, statements and general standards. The second, regarding prevention against disasters, the anti-fire system including construction of GIS materials and the Risk Map following investigation the present condition, premising improvement of relevant laws and regulations, should be planned. The third, we should consider, regarding utilize, educational application by the each tomb's story and royal ancestral rite, tourism by the local area of each tomb and industrial application by science and IT technologies.

• Korean Journal of Remote Sensing
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• v.33 no.5_3
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• pp.889-900
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• 2017

In this study, we analyzed the paper about NIR (Near-Infrared) remote sensing data and systematically summarized the research and application fields of NIR. To do this, we conducted a case study on the use of NIR in domestic journals, and SCI journals in the field of technology development for the last 5 years. After selection, a total of 281 journals were analyzed. For the statistical analysis, the classification was divided into subclasses and the dominant research trends were examined. As a result, the researchers who wrote the papers made the highest score of about 60% or more at university. In the field of application, 50% of land, 30% of environment, and 11% of disaster were distributed on SCI journals. In Korea, on the other hand, 55% of land, 24% of environment and 10% of disasters were distributed. In addition, 17% of the national land management and 8% of the geological / natural resources. Disaster observation using NIR was used for landslide, drought, weather disaster and flood. In particular, meteorological disasters are a result of study on Asian dust. However, there were no results of forest fire detection in Korea. Considering the domestic situation, it seems necessary to carry out additional and active research on this. It is expected that this statistical analysis data will be used as basic data to help expand the NIR technology development and utilization field in Korea in the future.