• Journal of Radiation Protection and Research
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• 제41권2호
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• pp.101-104
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• 2016

Background: To protect the public from natural radioactive materials, the 'Act on safety control of radioactive rays around living environment" was established in Korea. There is an annual effective dose limit of 1 mSv for products, but the activity concentration limit for products is not established yet. Materials and Methods: To suggest the activity concentration limits for consumer goods containing NORM, in this research, we assumed the "small room model" surrounding the ICRP reference phantom to simulate the consumer goods in contact with the human bodies. Using the Monte Carlo code MCNPX, we evaluate the effective dose rate for the ICRP reference phantom in a small room with dimension of phantom size and derived the activity concentration limit for consumer goods. Results and Discussion: The consumer goods have about 1600, 1200 and $19000Bq{\cdot}kg^{-1}$ for $^{226}Ra$, $^{232}Th$ and $^{40}K$, and the activity concentration limits are about six times comparing with the values of building materials. We applied the index to real samples, though we did not consider radioactivity of $^{40}K$, indexes of the some samples are more than 6. However, this index concept using small room model is very conservative, for the consumer goods over than index 6, it is necessary to reevaluate the absorbed dose considering real usage scenario and material characteristics. Conclusion: In this research, we derived activity concentration limits for consumer goods in contact with bodies and the results can be used as preliminary screening tool for consumer goods as index concept.

• 한국콘텐츠학회논문지
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• 제15권1호
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• pp.221-232
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• 2015

남자 고등학생이 인지하는 삶의 질, 가족건강성, 자아탄력성이 학교적응에 미치는 영향을 확인하여 성공적인 학교적응을 위한 교육 프로그램 개발에 기초가 되는 자료를 제공하고자 서술적 상관관계 조사연구를 실시하였다. A시 소재의 1학년, 2학년 남자 고등학생 569명을 대상으로 삶의 질, 가족건강성, 자아탄력성과 학교적응과의 상관관계를 분석하고, 학교적응에 영향을 미치는 요인을 파악하기 위해 t-test와 ANOVA, 다중회귀분석(multiple regression analysis)을 실시하였다. 그 결과 아버지 직업, 어머니 학력, 학업성적, 경제 수준, 흡연과 음주 유무, 자살시도나 자살생각이 학교적응에 통계적 유의한 차이를 나타냈고, 학업성적, 자살생각, 삶의 질, 가족건강성, 자아탄력성이 학교적응의 영향 요인으로 나타났고, 설명력은 61.4%이었다. 그러므로 학생들의 삶의 질, 가족건강성, 자아탄력성을 증진시켜주며, 삶의 질을 높여줄 수 있는 학교와 가정, 사회가 연계된 프로그램의 시행이 필요하다.

• 암석학회지
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• 제10권3호
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• pp.222-232
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• 2001

이차이온질량분석기는 고속으로 가속된 일차이온을 고체 시료 표면에 충돌시켜, 이차이온을 발생시킨 후 질량분석 장치를 통해 분석하는 장치이다. 시료에 충돌하는 일차이온빔의 크기를 마이크론 단위까지 줄여 미세영역에 대한 분석이 가능하므로 이온현미분석기라고도 불린다. 이차이온질량분석기의 정밀도와 정확도는 고전적인 질량분석기에 비해 떨어진다. 하지만, 극소량의 시료로 분석이 가능하며, 화학적 전처리 과정 없이 연마편을 이용하여 매우 좁은 영역에서 동위원소의 분포를 연구할 수 있다는 장점이 있다. 지구화학/우주화학 분야에서 이차이온질량분석기의 활용은 최근 급속히 증가하고 있으며, 주로 (1) 수소, 탄소, 산소, 황 등의 안정동위원소 연구, (2) 함 우라늄/토륨 광물의 절대연령측정, (3) 광물 내 미량원소의 분포 연구, (4) 선태양계 광물 발견 및 이들의 동위원소 연구 등에 사용되고 있다.

• Journal of Electrochemical Science and Technology
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• 제5권1호
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• pp.32-36
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• 2014

The $0.3Li_2MnO_3{\cdot}0.7LiMn_{0.55}Ni_{0.30}Co_{0.15}O_2$ cathode material was prepared via a co-precipitation method. The vapor grown carbon fiber (VGCF) was used as a conductive material and its effects on electrochemical properties of the $0.3Li_2MnO_3{\cdot}0.7LiMn_{0.55}Ni_{0.30}Co_{0.15}O_2$ cathode material were investigated. From the XRD pattern, the typical complex layered structure was confirmed and a solid solution between $Li_2MnO_3$ and $LiMO_2$ (M = Ni, Co and Mn) was formed without any secondary phases. The VGCF was properly distributed between cathode materials and conductive sources by a FE-SEM. In voltage profiles, the electrode with VGCF showed higher discharge capacity than the pristine electrode. At a 5C rate, 146 mAh/g was obtained compared with 232 mAh/g at initial discharge in the electrode with VGCF. Furthermore, the impedance of the electrode with VGCF did not changed much around $9-10{\Omega}$ while the pristine electrode increased from 21.5${\Omega}$ to $46.3{\Omega}$ after the $30^{th}$ charge/discharge cycling.

• 한국의류산업학회지
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• 제8권2호
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• pp.225-232
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• 2006

This study purposed to review the concept and characteristics of subculture theoretically and then to analyze subcultural hairstyles shown in the 20th century's fashion in terms of form, structure, texture, design line and design principle, which were formative factors of beauty art. The range of this study was from the 1950's to the 1990's, during which subcultural hairstyles, which were selected for this study, kept a unique formality as subcultural characteristics of each time were reflected in hairstyles. The hairstyles found in subcultural styles were reviewed as follows. From the formative analysis as the above, it was concluded that layer form was seen most frequently in the subcultural hairstyles. This may be because it has a lot of layers in hair, and enables to make more various forms with a simpler care than other hairstyles so that it is easy to show one's own characteristic or differentiate oneself from others. Thanks to the characteristics of layer form, horizontal and convex were often seen as design lines. As for a texture, straight often appeared. The texture of straight is naturally formed without any care applied on hair. The reason may be that most subcultures refused artificiality. Therefore, the characteristics of subcultural hairstyles may be that hairstyles are transformed into various forms and created into the styles appropriately for individual tastes so as to clearly express one's own idea and thought.

• 대한한방내과학회지
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• 제20권1호
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• pp.232-243
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• 1999

In the Oriental Medicine, the breathing problem is defined as one of the symptoms such as Cheon-Jeung, Hyo-Jeung and chronic respiratory organs disease. Its source is heard to be the functional reduction of descending of Lung and Kidney. The organs for breathing are known as Lung, Spleen and Kidney. In this research, some remarkable results are referred which were detected by measuring the variations of the breathing volume of 20 patients after taking Keumsuyukunjeon. Picrometer is used for the measurement of the volume. The investigation had been performed since from January 1 st to August 31th of 1998. The patients for the experiment were mainly composed of patients who had trouble in breathing due to the pneumonectasis, sthmas, pneumonias. The percent of men is 67% in sex distribution and the ratio of persons over 50's was 85%. After Keumsuyukunjeon was taken to the patients, the enhancement ratio of breathing volume was appeared as 7.7%. The analysis based on an age was that the patients of 40's show the highest volumetric advancement. The ratio of breathing volume was the aged patients whose lung or kidney is weak and it can be used as the prescription for supplement of body and lung. From the relations between the breathing volume before treatment and the enhancement ratio, the increase of the enhancement ratio and the better response to the medicine were shown to the more serious patients. The period of treatment was 27.5 days average. The enhancement ratio of smoker was 23. and that of non-smoker was 50. At the test of relation between the trouble rate in breathing and the enhancement ratio. Grade Ⅲ shows the highest enhancement value 50%. From the experimental results, It is found that Keumsuyukunjeon gives a noticeable benefit for the patients whose main symptom was breathing problem. Long-term treatments for the serious and aged patients will make much more efficient to the reduction of the symptoms.

• Child Health Nursing Research
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• 제14권3호
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• pp.232-242
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• 2008

Purpose: The purpose of this study was to develop a safety education program for elementary school students by comparing elementary school teachers and students on their demands for safety education. Method: The data were collected from 1,754 1-6th grade elementary school students and 335 elementary school teachers (6 elementary schools) using self- report questionnaires. Results: 1) The mean score for level of demand for safety education by elementary school teachers was 4.43 ({\pm}.44$) and for students, 4.01({\pm}.65$). 2) There was a significant difference in the level of demand for safety education between the elementary school teachers and students (t=-14.46, p=.000). 3) There were significant differences in the level of demand for safety education according to teachers' gender (t=-4.36, p=.000), teachers' concern about a safe life (t=5.14, p=.000), teachers' perception of a safe life (t=3.08, p=.002), students' gender (t=-3.89, p=.000), students' grade (t=5.06, p=.000), students' concern about safe life (t=13.09, p=.000), students' safe life practices (t=11.64, p=.000), students' previous experience of safety education (t=2.02, p=.045), and students' recognition of the importance of safety education (F=67.31, p=.000). Conclusion: To develop effective safety education programs for elementary school students, it is necessary to give precedence to demands and interest in safety education of the students.

• Journal of Astronomy and Space Sciences
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• 제29권2호
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• pp.221-232
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• 2012

We analyzed the manufacturing procedure, specifications, repair history, and details of celestial movements of the water-hammering type $Honsang$ (celestial globe). Results from our study on the remaining $Honsangs$ in China and Japan and on the reconstruction models in Korea were applied to our conceptual design of the water-hammering type $Honsang$. A $Honui$ (armillary sphere) and $Honsang$ using the water-hammering method were manufactured in $Joseon$ in 1435 (the 17th year of King $Sejong$). $Jang$ $Yeong-Sil$ developed the $Honsang$ system based on the water-operation method of $Shui$ $y{\ddot{u}}n$ $i$ $hsiang$ $t'ai$ in China. Water-operation means driving water wheels using a water flow. The most important factor in this type of operation is the precision of the water clock and the control of the water wheel movement. The water-hammering type $Honsang$ in $Joseon$ probably adopted the $Cheonhyeong$ (天衡; oriental escapement device) system of $Shui$ $y{\ddot{u}}n$ $i$ $hsiang$ $t'ai$ in China and the overflow mechanism of $Jagyeongnu$ (striking clepsydra) in $Joseon$, etc. In addition to the $Cheonryun$ system, more gear instruments were needed to stage the rotation of the $Honsang$ globe and the sun's movement. In this study, the water-hammering mechanism is analyzed in the structure of a water clock, a water wheel, the $Cheonhyeong$ system, and the $Giryun$ system, as an organically working operation mechanism. We expect that this study will serve as an essential basis for studies on $Heumgyeonggaknu$, the water-operating astronomical clock, and other astronomical clocks in the middle and latter parts of the $Joseon$ dynasty.

• Journal of Photoscience
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• 제12권1호
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• pp.1-9
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• 2005

The ubiquitin E3 ligase COP1 (Constitutive Photomorphogenesis 1) is a protein repressor of photomorphogenesis in Arabidopsisplants, and it found in various organisms, including animals. The COP1 protein regulates the stability of many of the light-signaling components that are involved in photomorphogenesis and in the developmental processes. To study the effect of COP1 on flowering in a short day plant, we have cloned a full-length of PnCOP1 (Pharbitis nil COP1) cDNA from Pharbitis nil Choisy cv. Violet, and we examined its transcript levels under various conditions. A full-length PnCOP1 cDNA consists of 2,280 bp nucleotidesthat contain 47 bp of 5'-UTR, 232 bp of 3'-UTR including the poly (A) tail, and 1,998 bp of the coding sequence. The deduced amino acid sequence contains 666 amino acids, giving it a theoretical molecular weight of 75 kD and a isolectric point of 6.2. The PnCOP1 contains three distinct domains, an N-terminal $Zn^2+$-binding RING-finger domain, a coiled-coil structure, and WD40 repeats at the C-terminal, implying that the protein plays a role in protein-protein interactions. The PnCOP1 transcript was detected in the cotyledon, hypocotyls and leaves, but not in root. The levels of the PnCOP1 transcript were reduced in leaves that were a farther distance away from the cotyledons. The expression level of the PnCOP1 gene was inhibited by light, while the expression was increased in the dark. During the floral inductive 16 hour-dark period for Pharbitis nil, the expression was increased and it reached its maximum at the 12th hour of the dark period. The levels of PnCOP1 mRNA were dramatically reduced upon light illumination. These results suggest that PnCOP1 may play an important function in the floral induction of Pharbitis nil.

• 대한치과기공학회지
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• 제41권3호
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• pp.221-232
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• 2019

Purpose: This experiment aims to provide the fundamental resources in developing a programme intended to prevent students from dropping out of their academics by promoting students to develop an optimistic psychological state, through analysis of the factors that influence students' commitment to their major. Methods: A self-administered questionnaire was conducted from $19^{th}$ of November of the year 2018, till $1^{st}$ of December of the same year, with dental technology students located in W city as the subject. 261(93.2%) of the participants' responses were used for the final analysis. Results: A negative association between factors of commitment to major and factors of academic dropout decision were portrayed to be of statistical significance (p<.01), and factors of commitment to major that influence dropping out of their academics were shown to be that of 'autotelic experience' (p<.001) with a negative ( - ) relationship, and 'change in a sense of time' (p<.01) with a positive ( + ) relationship of statistical significance, while the explanatory power of the model was shown to be 33.6%. Conclusion: In order to prevent dental technology students from dropping out of their academics, following their entrance, To achieve this, the department must consider the implementation of, aside from subject matters of the major, other various extra-curricular programmes, and programmes in which the supervisor is consistently providing consultations that are tailored to each individual student.