• 한국환경과학회지
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• 제31권7호
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• pp.637-652
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• 2022

In this study, the contributions of emissions (foreign and domestic) and atmospheric physical and chemical processes to PM_2.5 concentrations were evaluated during a high PM_2.5 episode (March 24-26, 2018) observed on the Jeju Island in the spring of 2018. These analyses were performed using the community multi-scale air quality (CMAQ) modeling system using the brute-force method and integrated process rate (IPR) analysis, respectively. The contributions of domestic emissions from South Korea (41-45%) to PM_2.5 on the Jeju Island were lower than those (81-89%) of long-range transport (LRT) from China. The substantial contribution of LRT was also confirmed in conjunction with the air mass trajectory analysis, indicating that the frequency of airflow from China (58-62% of all trajectories) was higher than from other regions (28-32%) (e.g., South Korea). These results imply that compared to domestic emissions, emissions from China have a stronger impact than domestic emissions on the high PM_2.5 concentrations in the study area. From the IPR analysis, horizontal transport contributed substantially to PM_2.5 concentrations were dominant in most of the areas of the Jeju Island during the high PM_2.5 episode, while the aerosol process and vertical transport in the southern areas largely contributed to higher PM_2.5 concentrations.

• Nutrition Research and Practice
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• 제9권5호
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• pp.511-516
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• 2015

BACKGROUND/OBJECTIVES: This study aims to determine contribution of meal frequency, self-efficacy for healthy eating, and availability of healthy foods towards diet quality of adolescents in Kuala Lumpur, Malaysia. SUBJECTS/METHODS: This study was conducted among 373 adolescents aged from 13 to 16 years old. Diet quality of the respondents was assessed using the Healthy Eating Index for Malaysians. Meal frequency, self-efficacy for healthy eating, and availability of healthy foods were assessed through the Eating Behaviours Questionnaire (EBQ), self-efficacy for healthy eating scale, and availability of healthy foods scale, respectively. RESULTS: The majority of the respondents (80.7%) were at risk of poor diet quality. Males ($mean=34.2{\pm}8.2%$) had poorer diet quality than females ($mean=39.9{\pm}9.0%$) (t = -5.941, P < 0.05). Malay respondents ($mean=36.9{\pm}8.7%$) had poorer diet quality than Indian respondents ($mean=41.3{\pm}10.0%$) (F = 2.762, P < 0.05). Age (r = 0.123, P < 0.05), self-efficacy for healthy eating (r = 0.129, P < 0.05), and availability of healthy foods (r = 0.159, P < 0.05) were positively correlated with the diet quality of the respondents. However, meal frequency was not correlated with the diet quality of the respondents. Multiple linear regression analysis showed that being a male, being a Malay, low self-efficacy for healthy eating, and low availability of healthy foods contributed significantly towards poor diet quality among respondents. CONCLUSIONS: In short, sex, ethnicity, self-efficacy for healthy eating, and availability of healthy foods were associated with diet quality among adolescents. Health practitioners should take into consideration of differences in sex and ethnicity during implementation of nutrition-related intervention programs. Self-efficacy for healthy eating and availability of healthy foods should be included as important components in improving diet quality of adolescents.

• Journal of Nutrition and Health
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• 제46권2호
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• pp.186-196
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• 2013

The objective of this study was to develop a semi-quantitative food frequency questionnaire (FFQ) for an adult population for use in the Korea National Health and Nutrition Examination Survey (KNHANES). The 24-hour recall data for 2,939 subjects aged 19 years and over from the fourth KNHANES first year (2007) were used to extract the items included in the questionnaire. The FFQ items were developed by selection of major dishes based on the cumulative contribution rate, between-person variability based on the cumulative R2 of energy and 14 nutrients (carbohydrate, protein, fat, crude fiber, calcium, phosphorous, iron, sodium, potassium, vitamin A, thiamin, riboflavin, niacin, and vitamin C) and the number of consumers of each dish. In addition, the FFQ items were revised with analysis of 24-hour recall data of the fourth KNHANES second and third year (2008, 2009). Finally, 112 items were included in the FFQ and grouped as follows: rice (5 items), noodles and dumplings (6), breads and rice cakes (8), soups and stews (12), soybeans, eggs, meat and fish (23), vegetables, seaweed and potatoes (27), milk and dairy products (4), fruits (13), beverages (5), snacks (6) and alcoholic beverages (3). The food items of FFQ accounted for an average of 87.0% of energy and 14 nutrient intakes and also accounted for 81.7% of the between-person variability. The frequency range of the FFQ items was classified into nine categories (never or seldom, once per month, 2-3 times per month, once per week, 2-4 times per week, 5-6 times per week, once per day, twice per day and three times per day) and the portion size was divided into three categories (small, medium and large). We expect that this developed dish-based FFQ could be used in assessment of longterm dietary intakes of Korean adults.

• 한국콘텐츠학회논문지
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• 제8권10호
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• pp.129-141
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• 2008

본 연구는 설문을 통해 종합부동산세에 대한 국민들의 인식을 분석하였다. 분석 결과 종합부동산세의 과세대상이 되는 주택가격대 6억원 초과의 주택을 보유하고 있는 경우가 6억원 이하의 주택의 경우보다 종합 부동산세 세율의 적정성에 대해서 부정적으로 인식하는 경우가 많았으며 토지에 대한 종합부동산세의 경우도 동일한 결과를 나타내었다. 또한 종합부동산세의 정책에 대하여 소득재분배, 부동산투기억제, 과세불공평해소 측면에서는 종합부동산세가 긍정적 역할을 하는 것으로 나타났고, 국가균형발전 측면에 대해서는 부정적 역할을 하는 것으로 나타났다. 한편 국민들은 보유단계의 조세와 양도단계에서의 조세를 연계한 종합적인 세무계획을 갖고 있는 것으로 나타났다.

• 한국환경과학회지
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• 제23권11호
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• pp.1889-1907
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• 2014

The characteristics of meteorological conditions related to changes in atmospheric environment on Jeju Island were investigated during recent years (2010-2012). This analysis was performed using the hourly observed data of meteorological variables (air temperature, wind speed and direction) and air pollutants ($O_3$, $PM_{10}$, $SO_2$, $NO_2$, and CO). Out of 5 pollutants, $O_3$ and $PM_{10}$ concentrations have frequently exceeded national environmental standards in the study area during the study period, with relatively higher concentrations than the others. The concentrations of $O_3$ and $PM_{10}$ in 2010 and 2011 were somewhat higher than those in 2012, and their highest concentrations were mostly observed in spring followed by fall. Nighttime $O_3$ concentrations (with relatively high concentration levels) were almost similar to its daytime concentrations, due to less $O_3$ titration by very low NO concentrations in the target area and in part to $O_3$ increase resulting from atmospheric transport processes. The transport effect related to the concentration variations of $O_3$ and $PM_{10}$ was also clarified in correlation between these pollutants and meteorological variables, e.g. the high exceedance frequency of concentration criteria with strong wind speed and the high concentrations with the westerly/northwesterly winds (e.g., transport from the polluted regions of China). The overall results of this study suggest that the changes in atmospheric environment in the study area were likely to be caused by the transport effect (horizontal and vertical) due to the meteorological conditions rather than the contribution of local emission sources.

• Structural Engineering and Mechanics
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• 제9권3호
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• pp.241-256
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• 2000

The major sources of energy dissipation in steel frames with partially restrained (PR) connections are evaluated. Available experimental results are used to verify the mathematical model used in this study. The verified model is then used to quantify the energy dissipation in PR connections due to hysteretic behavior, due to viscous damping and at plastic hinges if they are formed. Observations are made for two load conditions: a sinusoidal load applied at the top of the frame, and a sinusoidal ground acceleration applied at the base of the frame representing a seismic loading condition. This analytical study confirms the general behavior, observed during experimental investigations, that PR connections reduce the overall stiffness of frames, but add a major source of energy dissipation. As the connections become stiffer, the contribution of PR connections in dissipating energy becomes less significant. A connection with a T ratio (representing its stiffness) of at least 0.9 should not be considered as fully restrained as is commonly assumed, since the energy dissipation characteristics are different. The flexibility of PR connections alters the fundamental frequency of the frame. Depending on the situation, it may bring the frame closer to or further from the resonance condition. If the frame approaches the resonance condition, the effect of damping is expected to be very important. However, if the frame moves away from the resonance condition, the energy dissipation at the PR connections is expected to be significant with an increase in the deformation of the frame, particularly for low damping values. For low damping values, the dissipation of energy at plastic hinges is comparable to that due to viscous damping, and increases as the frame approaches failure. For the range of parameters considered in this study, the energy dissipations at the PR connections and at the plastic hinges are of the same order of magnitude. The study quantitatively confirms the general observations made in experimental investigations for steel frames with PR connections; however, proper consideration of the stiffness of PR connections and other dynamic properties is essential in predicting the dynamic behavior.

• 유통과학연구
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• 제17권5호
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• pp.95-102
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• 2019

Purpose - The purpose of the research is to identify the demographic characteristics of the customers with high private label purchase intention. According to the previous research demographics such as gender, age, income, and residence type affect private label purchase intention indirectly through psychographics rather than directly. For instance, higher income group is time pressured, price-insensitive, quality-sensitive, less likely to enjoy shopping utilitarian products, and less likely to be variety-seeking. The main contribution of this research is to verify the results found in the previous empirical foreign research using scanner data and to investigate the differences of the characteristics of private label users between Korea and the foreign countries. Research design, data, and methodology - In order to empirically test the proposed hypotheses, scanner data of a Korean major super center was analyzed. Results - Empirical results show that private labels are more favored by old people over 50s, dwellers in individual house, lower income group, and frequent store visitors. Age of 30s, dwellers in the apartment of 30 pyung, higher income group, and consumers who purchased a large amount are less likely to purchase private labels. Gender turned out not to affect private label purchase. It should be noted that there is a significant multicollinearity among independent variables. Conclusions - The research findings provide managerial implication for retailers' private label strategy. In general, retailers heavily send private label coupons to the customers with high purchase volume. According to the research, however, store visit frequency is much more positively associated with private label purchase than purchase amount. The study has some limitations. The samples are only consumers with private label purchase experience. The data were drawn from one store and only 8 commodity products were used for the analysis. Also, if more demographics were available, a more complete description on the private brand users' profile could have been derived. We propose the following future research. Research using the data including consumers without private label experience, research investigating direction of causality between private label loyalty and store loyalty, and research using hedonic private label products such as TV and PC could be promising.

• Journal of Preventive Medicine and Public Health
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• 제46권1호
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• pp.28-38
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• 2013

Objectives: This study aimed to collect information that will help enhance the social networks and improve the quality of life among elderly people by observing the relationship between their social network and health-related quality of life (HRQoL) and by analyzing social network factors affecting HRQoL. Methods: This study was based on the 2008 Community Health Survey in Yeoncheon County. Three hundred elders were included in the study population. We compared the revised Lubben Social Network Scale (LSNS-R) score and Euro quality of life-5 dimensions health status index by demographic characteristics and chronic disease prevalence. We analyzed the data using multiple regression and tobit regression by setting the HRQoL as the dependent variable and social network and other characteristics as the independent variables. We analyzed social network factors by using factor analysis. Results: The LSNS-R score differed significantly according to age and existence of a spouse. According to the results from the hierarchical multiple regression analysis, the LSNS-R explained 0.10 of the variance and LSNS-R friends factor explained 0.10 of the variance. The tobit regression indicated that the contribution of the LSNS-R family size factor to the regression coefficient of the independent variable that affected the HRQoL was $B_T$=2.96, that of the LSNS-R family frequency factor was $B_T$=3.60, and that of LSNS-R friends factor was $B_T$=5.41. Conclusions: Social networks among elderly people had a significant effect on HRQoL and their networks of friends had a relatively higher effect than those of family members.

• 한국습지학회지
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• 제20권2호
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• pp.116-123
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• 2018

산림생태계에서 대기로의 토양의 이동은 토양 호흡이라는 과정을 통해 이루어진다. 본 연구에서는 임령이 다른 잣나무림을 대상으로 생육기 동안의 토양 호흡값과 토양 내 뿌리의 양, 미생물 개체군 생물량을 측정하여, 토양호흡량이 임령에 따라 어떻게 다르며, 뿌리와 미생물 개체군이 얼마나 기여할 것인지 알아보고자 하였다. 토양 온도와 토양 호흡은 임령과는 상관없이 유사한 패턴을 보여 7월까지는 증가하고 이후 감소하였다. 산림의 임령이 높을수록 토양 호흡량이 대체적으로 높았다. 토양 내 뿌리와 미생물을 조사한 결과, 임령이 높을수록 토양 내 존재하는 지름 2 mm 이하인 세근의 양이 많았으며 토양 미생물 개체군의 생물량이 많았다. 토양에서 뿌리를 제거하였을 때 70년 숲은 변화가 없었으나, 40년 숲에서는 토양 호흡값이 감소하였다. 본 연구결과로 볼 때, 산림의 연령이 높아질수록 토양 호흡량이 커지며, 식물 뿌리와 특히 토양 미생물이 토양 호흡값에 많은 기여를 하고 있는 것으로 생각해 볼 수 있다.

• Advances in concrete construction
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• 제12권5호
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• pp.377-389
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• 2021

Reinforced concrete vertical silos are universal structures that store large amounts of granular materials. Due to the asymmetric structure, heavy load, uneven storage material distribution, and the difference between the storage volume and the storage material bulk density, the corresponding earthquake is very complicated. Some scholars have proposed the calculation method of horizontal forces on reinforced concrete vertical silos under the action of earthquakes. Without considering the effect of torsional effect, this article aims to reveal the expansion factor of the silo group considering the torsional effect through experiments. Through two-way seismic simulation shaking table tests on reinforced concrete column-supported group silo structures, the basic dynamic characteristics of the structure under earthquake are obtained. Taking into account the torsional response, the structure has three types of storage: empty, half and full. A comprehensive analysis of the internal force conditions under the material conditions shows that: the different positions of the group bin model are different, the side bin displacement produces a displacement difference, and a torsional effect occurs; as the mass of the material increases, the structure's natural vibration frequency decreases and the damping ratio Increase; it shows that the storage material plays a role in reducing energy consumption of the model structure, and the contribution value is related to the stiffness difference in different directions of the model itself, providing data reference for other researchers; analyzing and calculating the model stiffness and calculating the internal force of the earthquake. As the horizontal side shift increases in the later period, the torsional effect of the group silo increases, and the shear force at the bottom of the column increases. It is recommended to consider the effect of the torsional effect, and the increase factor of the torsional effect is about 1.15. It can provide a reference for the structural safety design of column-supported silos.