• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.241.1-241.1
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• 2014

The large-area high-power radio-frequency (RF) driven ion sources based on the negative hydrogen (deuterium) ion beam extraction are the major components of neutral beam injection (NBI) systems in future large-scale fusion devices such as an ITER and DEMO. Positive hydrogen (deuterium) RF ion sources were the major components of the second NBI system on ASDEX-U tokamak. A test large-area high-power RF ion source (LAHP-RaFIS) has been developed for steady-state operation at the Korea Atomic Energy Research Institute (KAERI) to extract the positive ions, which can be used for the NBI heating and current drive systems in the present fusion devices, and to extract the negative ions for negative ion-based plasma heating and for future fusion devices such as a Fusion Neutron Source and Korea-DEMO. The test RF ion source consists of a driver region, including a helical antenna and a discharge chamber, and an expansion region. RF power can be transferred at up to 10 kW with a fixed frequency of 2 MHz through an optimized RF matching system. An actively water-cooled Faraday shield is located inside the driver region of the ion source for the stable and steady-state operations of RF discharge. The characteristics and uniformities of the plasma parameter in the RF ion source were measured at the lowest area of the expansion bucket using two RF-compensated electrostatic probes along the direction of the short- and long-dimensions of the expansion region. The plasma parameters in the expansion region were characterized by the variation of loaded RF power (voltage) and filling gas pressure.

• 한국식생활문화학회지
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• 제13권2호
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• pp.107-118
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• 1998

A nutrition education program for teachers and caregivers of the preschool children can be most effective when it is based on a comprehensive needs assessment dealing with sociodemographic factors, dietary habits, and nutrition. The purpose of the present study was to investigate current dietary habits and nutrition knowledge of the teachers and caregivers of the day-care centers. Two hundred forty two teachers and caregivers were administered a questionnaire which was designed to ascertain informations on sociodemographic data, dietary habits and nutrition knowledge. Dietary habits of the teachers were found to be significantly different by sociodemographic variables; breakfast skipping/meal irregularities (age, p=0.011); frequency of snacking (education level p=0.031); preference for salty taste(age, p = 0.000, marital status p=0.038); preference for sweet tarte (age p=0.009); preference for vegetables (income level p=0.050); frequency of eating out (age p=0.028, marital status p=0.001); frequency of coffee drinking (age p=0.019). Daycare center teachers' nutrition knowledge level was found to be less than adequate expecially on nutrients that are liable to be deficient in young growing children and their food sources. Proportions of the teachers who answered correctly to the questions on foods rich in vitamin A, iron content of milk, bioavailability of calcium in plant foods were as low as 20.2%-54.5%. The most frequently used sources of nutrition information were mass media such as TV, radio, newspaper and magazines. Only 2.9% of the subjects reported that they obtain nutrition information from health professionals such as nutritionists/dietitians, physicians, and nurses. These findings are applicable at the planning and implementation stages of various nutrition programs for the improvement of dietary habits and nutrition knowledge of the teachers and caregivers of the daycare centers. Further studies are needed to investigate the effects of teachers' dietary of habits and nutrition knowledge on food habits of young growing children.

• 한국식품조리과학회지
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• 제7권4호
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• pp.23-34
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• 1991

This study was to investigate consumer recognition of food safety and food additives. The results of this study are as follows: 1. When shopping for food, the food safety was rated as foremost concern for the respondents and the details checked most often were manufacture date, packing condition and axpiration date, respectively. When asked their opinion about harmful factors in relation to food safety, the most important consideration was food additives. The highest rating for credibility regarding the sources of information on food was given to scientists in university and institute, lowest one was given to food manufacturer. 2. Government regulation on the use of food additives was known to exist, but control of the uses of food additive was considered inadequate by 60% of the respondents. These results showed significant differences for age (p<0.05), for education level (p<.01) and for income (p<.05) respectively. 3. 47.9% of the respondents indicated that they were willing to purchase the additive free foods, although it was expensive. More than 70% made an effort to eat food with less food additive and were concerned about possible effects of food additives on health, showing significant differences for age (p<0.05), for education level (p<0.05) and for income (p<0.05). 4. Labeling for food additive found on food package was shown to be unsatisfactory, showing significant difference only for income (p<0.05) and more information about food was needed by over 91.3% of the respondents, showing significant difference for education level (p<0.05). 5. Although approximately 80% of the respondents were concerned about artificial preservative, artificial flavor, artificial color and artificial sweetener, the concern about artificial preservative was the highest. Primary causes that respondents felt fear toward food additives were the unknown harms and cancer, and primary sources that respondents got information on food were televison and radio, respectively. From these results, it was shown that consumer considered food safety important and they felt a great deal of concern about food additives.

• 천문학회지
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• 제37권4호
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• pp.281-284
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• 2004

Optical imaging and spectroscopy of G353.2+0.9, the brightest part of the giant H II region NGC 6357, shows that this H II region is optically thin, contains ${\~}300\;M_{\bigodot}$ of ionized gas and is probably expanding into the surrounding medium. Its chemical composition is similar to that found in other H II regions at similar galactocentric distances if temperature fluctuations are significant. The inner regions are probably made of thin shells and filaments, whereas extended slabs of material, maybe shells seen edge-on, are found in the periphery. The radio continuum and H$\alpha$ emission maps are very similar, indicating that most of the optical nebula is not embedded in the denser regions traced by molecular gas and the presence of IR sources. About $10^{50}$ UV photons per second are required to produce the H$\beta$ flux from the 1l.3'${\times}$10' region surrounding the Pis 24 cluster that is south of G353.2+0.9. Most of the energy powering this region is produced by the 03-7 stars in Pis 24. Most of the 2MASS sources in the field with large infrared excesses are within G353.2+0.9, indicating that the most recent star forming process occured within it. The formation of Pis 24 preceded and caused the formation of this new generation of stars and may be responsible for the present-day morphology of the entire NGC 6357 region.

• 천문학회보
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• 제36권2호
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• pp.147.2-147.2
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• 2011

We have initiated a long-term identification campaign of supernova remnant candidates in X-ray regime. In the short-listed unidentified sources from the ROSAT All Sky Survey, we have chosen the brightest candidate, G308.3-1.4, as our pilot target for a dedicated investigation with Chandra X-ray Observatory. Our observation has revealed an incomplete shell-like X-ray structure which well-correlated with the radio feature. Together with the spectral properties of a shocked heated plasma, we confirm that G308.3-1.4 is indeed a supernova remnant. A bright X-ray point source which locates close to the remnant center is also uncovered in this observation. Its spectral behavior conform with those observed in a rare class of neutron stars. The properties of its optical/infrared counterpart suggests the evidence for a late-type companion star. Interestingly, possible excesses in B-band and H-alpha have been found which indicate this can be an accretion-powered system. With the further support from the putative periodicity of ~1.4 hrs, this source can possibly provide the direct evidence of a binary system survived in a supernova explosion for the first time.

• 천문학회보
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• 제41권1호
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• pp.49.2-49.2
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• 2016

MIRIS Paschen-${\alpha}$ ($Pa{\alpha}$) Galactic Plane Survey (MIPAPS) presents the first whole Galactic plane (with the width of $-3^{\circ}$ < b < $+3^{\circ}$) map for the $Pa{\alpha}$ emission line. Many of $Pa{\alpha}$ features were detected more brightly than the previous observed $H{\alpha}$ features, and they coincide well with dense cloud regions. This means that newly detected $Pa{\alpha}$ blobs can indicate massive star forming regions (H II regions) screened by foreground clouds around Galactic plane. Anderson et al. (2014) presented the most complete Galactic H II region catalog based on WISE 12 and 22 um data. Of the cataloged sources, only ~20% have measured radio recombination line (RRL) or $H{\alpha}$ emission, and the rest are still candidate H II regions. At first, we compare the MIPAPS results with Anderson's H II region catalog for the Cepheus region (Galactic longitude from $+96^{\circ}$ to $116^{\circ}$). From this, we will investigate how much MIPAPS can supplement the catalog, and show MIPAPS scientific potential. After that, we plan to extend this work to the whole plane, and finally catalog MIRIS $Pa{\alpha}$ blob sources for the whole Galactic plane.

• 보건교육건강증진학회지
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• 제19권1호
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• pp.31-44
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• 2002

This study was conducted to examine arthritis patients' knowledge level and its related factors. Data were collected from 100 people who suffered from arthritis in Seoul, Busan, Daegu, Daejun, Junjoo, and Pohang from June 1, 2000 to August 31, 2000. The results of this study are summarized as follows. 1. 61.0％ of the subjects was female. The incidence rate of arthritis was higher in the higher age group, lower educated group, and thinner group. In the case of male, the incidence rate was higher in the groups of single, residents in big cities, and technicians. In the case of female, it was higher in the groups of the married, residents in towns or villages, and housewives. 2. Among the sources of obtaining the knowledge related to arthritis, 38.0％ of the respondents obtained the knowledge from physicians and 24.1 ％ got it from TV or Radio. 14.6％ of them obtained it from family members, neighbors, and friends and 14.3％ got it from newspapers, magazines, and pamphlets. Only 5.8％ of them obtained the knowledge from pharmacists. The sources showed significant difference in the variables of age, occupation, marital status, religion, place of residence, and education level. 3. 47.2％ of them thought that education related to arthritis was needed without fail, while 12.5％ thought that it was not necessary. In the question related to concern about arthritis, ‘no concern’ was 31.2％, while ‘concern’ was 7.8％ and ‘a little concern’ was 45.1 ％. 4. The knowledge level of arthritis was 7.35 ± 1.51 points on the basis of 11 points. It showed significant difference in the variables of age, occupation, education level, and economic status. 5. The knowledge was influenced by the variables of economic status, necessity of publicity, treatment period, occupation, education level, and age. The arthritis patients did not have enough knowledge of arthritis because the education was not provided well for them. Therefore, related professionals and organizations must develop education program of arthritis in order to educate them.

• 천문학논총
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• 제30권2호
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• pp.129-131
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• 2015

We have initiated single-dish monitoring observations of ~400 methanol maser sources at 6.7 GHz using the Hitachi 32-m radio telescope from December 2012 to systematically research periodic flux variations, which are observed in some methanol maser sources associated with high-mass (proto-)stars. In our monitoring, we have made daily monitoring, so that each source has been observed every nine days with an integration time of 5 min (typical $3{\sigma}$ detection sensitivities of 0.9 Jy). The monitoring observations help us statistically understand periodic flux variations with a period longer than 50 days. As an initial result, we present a new detection of periodic flux variations in the 6.7 GHz methanol maser source G 036.70+00.09. The period of the flux variations is ~53 days (~0.019 cycles $day^{-1}$), and seems to be stable over 9 cycles, at least until the middle of August 2014.

• Journal of Preventive Medicine and Public Health
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• 제52권2호
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• pp.115-122
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• 2019

Objectives: The aim of this study was to assess knowledge, attitudes, and practices regarding tuberculosis (TB) in the general population in Timor-Leste. Methods: In the nationally representative cross-sectional 2016 Timor-Leste Demographic and Health Survey, 4622 men (aged 15-59 years) and 12 607 women (aged 15-49 years) were randomly selected using stratified multistage sampling and interviewed. Results: Overall, 66.9% of men and 62.8% of women were aware of TB, 4.4% of men and 12.6% of women had TB courtesy stigma, and 83.3% of men and 88.6% of women reported intention to receive TB treatment. The $mean{\pm}standard$ deviation overall TB knowledge score was $3.9{\pm}2.0$ (out of 8) among men and $3.0{\pm}1.8$ among women. In a multivariable linear regression analysis, among both men and women, older age, higher education, rural residence, and sources of TB information (family/friends, school/workplace, health care provider, Internet, television, and newspaper) were associated with higher TB knowledge scores. In addition, among women, higher wealth status and having heard about TB from the radio were associated with higher TB knowledge scores. Negative associations with TB courtesy stigma were found for urban residence and having heard about TB from family or friends among men, and for older age, higher TB knowledge, and TB information sources (family/friends and school/workplace) among women. Among both men and women, higher TB knowledge scores and having heard of TB from a health care provider were associated with intention to receive TB treatment. Conclusions: This study identified socio-demographic risk factors for deficiences in population-based TB knowledge in Timor-Leste; these findings should be considered when designing TB communication, prevention, and control strategies.

• Nuclear Engineering and Technology
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• 제54권10호
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• pp.3795-3802
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• 2022

NaI(Tl) scintillation materials are considered to be one of many materials that are used exclusively for γ-ray detection and spectroscopy. The gamma-ray spectrometer is not an easy-to-use device, and the accuracy of the numerical values must be carefully checked based on the rules of the calibration technique. Therefore, accurate information about the detection system and its effectiveness is of greater importance. The purpose of this study is to estimate, using an analytical-numerical formula (ANF), the purely geometric solid angle, geometric efficiency, and total efficiency of a cylindrical NaI(Tl) γ-ray detector with a side-through hole. This type of detector is ideal for scanning fuel rods and pipelines, as well as for performing radio-immunoassays. The study included the calculation of the complex solid angle, in combination with the use of various points like gamma sources, located axially and non-axially inside the through detector side hole, which can be applied in a hypothetical method for calibrating the facility. An extended γ-ray energy range, the detector, source dimensions, "source-to-detector" geometry inside the side-through hole, path lengths of γ-quanta photons crossing the facility, besides the photon average path length inside the detector medium itself, were studied and considered. This study is very important for an expanded future article where the radioactive point source can be replaced by a volume source located inside the side-trough hole of the detector, or by a radioactive pipeline passing through the well. The results provide a good and useful approach to a new generation of detectors that can be used for low-level radiation that needs to be measured efficiently.