• Journal of Environmental Science International
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• v.21 no.2
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• pp.217-231
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• 2012

Hourly concentrations of $PM_1$, $PM_{2.5}$ and $PM_{10}$, were investigated at Gangneung city in the Korean east coast on 0000LST October 26~1800LST October 29, 2003. Before the intrusion of Yellow dust from Gobi Desert, $PM_{10}$($PM_{2.5}$, $PM_1$) concentration was generally low, more or less than 20 (10, 5) ${\mu}g/m^3$, and higher PM concentration was found at 0900LST at the beginning time of office hour and their maximum ones at 1700LST around its ending time. As correlation coefficient of $PM_{10}$ and $PM_{2.5}$($PM_{2.5}$ and $PM_1$, and $PM_{10}$ and $PM_1$) was very high with 0.90(0.99, 0.84), and fractional ratios of $(PM_{10}-PM_{2.5})/PM_{2.5}((PM_{2.5}-PM_1)/PM_1)$ were 1.37~3.39(0.23~0.54), respectively. It implied that local $PM_{10}$ concentration could be greatly affected by particulate matters of sizes larger than $2.5{\mu}m$, and $PM_{2.5}$ concentration could be by particulate matters of sizes smaller than $2.5{\mu}m$. During the dust intrusion, maximum concentration of $PM_{10}$($PM_{2.5}$, $PM_1$) reached 154.57(93.19, 76.05) ${\mu}g/m^3$ with 3.8(3.4, 14.1) times higher concentration than before the dust intrusion. As correlation coefficient of $PM_{10}$ and $PM_{2.5}$(vice verse, $PM_{2.5}$, $PM_1$) was almost perfect high with 0.98(1.00, 0.97) and fractional ratios of $(PM_{10}-PM_{2.5})/PM_{2.5}((PM_{2.5}-PM_1)/PM_1)$ were 0.48~1.25(0.16~0.37), local $PM_{10}$ concentration could be major affected by particulates smaller than both $2.5{\mu}m$ and $1{\mu}m$ (fine particulate), opposite to ones before the dust intrusion. After the ending of dust intrusion, as its coefficient of 0.23(0.81, - 0.36) was very low, except the case of $PM_{2.5}$ and $PM_1$ and $(PM_{10}-PM_{2.5})/PM_{2.5}((PM_{2.5}-PM_1)/PM_1)$ were 1.13~1.91(0.29~1.90), concentrations of coarse particulates larger than $2.5{\mu}m$ greatly contributed to $PM_{10}$ concentration, again. For a whole period, as the correlation coefficients of $PM_{10}$, $PM_{2.5}$, $PM_1$ were very high with 0.94, 1.00 and 0.92, reliable regression equations among PM concentrations were suggested.

• Korean journal of communication and information
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• v.32
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• pp.113-146
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• 2006

This study explored how media and interpersonal communication affected voters in Busan mayoral by-election, focusing on the mutual relations among media use and attentive use of political campaign, interpersonal communication, and voting participation. Also, comparative analysis between image factor and the factor of political party influencing the decision of a candidate were examined. Additionally, it was analysed differential media effects on candidates' image. According to the results, the local media use and attentive use of political campaign had the influence on the increase of interpersonal communication about the election. Voters who had much interpersonal discussion with others participated more than voters who had less interpersonal discussion. Media use did not directly affect the participation of voting, but indirectly contributed to participation of voting through interpersonal discussion. The assumption of differential media effects on candidates image was partly proved. There were statistically significant differences in the factor of competence of candidates' image among three experimental groups (attentive use of TV discussion program, Internet web sites of two candidates, and printing materials of political advertisement). Furthermore, with three main vote variables, issues, candidates image, party identification, the results of comparative analysis between image factor and the factor of political party influencing the choice of a candidate suggested that a sense of oneness with a party was highly related to the choice of the candidates of the party, however, candidates' image was not related to the decision of a candidate. Political party had more impact on for whom to vote than candidates' image in this study.

• Radiation Oncology Journal
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• v.4 no.1
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• pp.35-43
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• 1986

Study patients with head and neck carcinoma were studied retrospectively to assess the impact of treatment on survival and local control rate by stage in the Dept of Radiation Therapy, Korea University Hae Wha Hospital between March 1981 and March 1986. Prior to definite radiotherapy, patients were evaluated by physical examination and radiologic studies including chest, laryngogram and CT scan and then these patients were grouped according to the American Joint Committee (AJC) staging system. They were treated with RT alone or postoperative irradiation to the dose of 7,200 cGy/8 weeks and 6,000 cGy/7 weeks respectively. The results were obtained and as follows; 1. Overall male to female sex ratio was 3.6:1. The peak age of patients with head and neck cancer was 6th decade. 2. In all patients treated by RT, the ratio of squamous cell 1 carcinoma to non-squamous cell carcinoma was 3.5:1 (60/77 patients). 3. The incidence according to the anatomic site of primary tumor was 22 cases in the larynx, 12 cases in PNS, 7 cases in nasopharynx, 6 cases in oropharynx, and 3 cases in hypopharynx. 4. According to AJC staging system,4 cases were Stage 1,7 in Stage II, 19 in Stage III and 27 in Stage IV. 5. The overall incidence of cervical lymph node metastases was $43\%$ and subdigatric and submaxillary triangle lymph nodes were the most frequent site of metastases. 6. Local control was achieved in $48\%$ of patients treated by radio-therapy. 7. The lung was the most common site for distant metastases, comprising 4 cases among 7 cases in which distant metastases occured. 8. The overall estimated 5-year survival rate was $43\%$ in the head and neck cancer treated with radiotherapy by life-table analysis.

• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.4
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• pp.268-276
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• 2007

Urban atmosphere may play as a harbinger for the future climate change with respect to temperature and $CO_2$ concentration. The Seoul metropolitan area is unique in rapid urbanization and industrialization during the last several decades, providing a natural $CO_2$ dome with increased temperature. This study was carried out to evaluate the feasibility of using the urban-rural environmental gradient in replacement of the IPCC mid-term scenario (after 30-50 years). For this, we measured atmospheric $CO_2$ concentration and air temperature at three sites with different degree of urbanization (Seoul, Suwon, and Icheon). Results from 11-month measurement can be summarized as follows: (1) The annual mean $CO_2$ concentration across 3 sites was in the order of Seoul (439 ppm) > Suwon (419 ppm) > Icheon (416 ppm), showing a substantial urban-rural environmental gradient. (2) The diurnal fluctuation in $CO_2$ concentration was greater in summer than in winter, showing the effect of photosynthesis on local $CO_2$ concentration. (3) The daily maximum $CO_2$ concentration was observed at 0500 LST in spring and summer, 0800 LST in autumn, and 0900 LST in winter, showing the sunrise-time dependence. (4) The observed hourly maximum $CO_2$ concentration averaged for the whole period was 446 ppm in Seoul at 0700 LST, while the minimum was 407 ppm in Suwon at 1500 LST. (5) Compared with the background atmospheric concentration of $CO_2$ in Anmyeon-do (377.4 ppm annual mean), $CO_2$ concentration of the study sites was higher by 14% in Seoul, by 10% in Suwon, and by 9% in Icheon. The observed $CO_2$ concentration in Seoul reached already 98% of the 2030-2040 projection (450 ppm) and 80% of the 2040-2050 projection (550 ppm) under the IPCC BAU scenario, showing a feasibility of using the $CO_2$ dome of Seoul as a natural experimental setting for the mid-term climate change impact assessment.

• Journal of dental hygiene science
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• v.11 no.6
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• pp.505-512
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• 2011

The purpose of this study was to examine the oral health behavior and awareness of teachers in community children's centers, the state of oral health care among children in the centers and the opinions of the teachers on child oral health education in a bid to gather information required for the development of oral health education programs geared toward community children's center teachers. The subjects in this study were 178 teachers who worked in 98 community children's centers in the city of Incheon. After a survey was conducted from April 28 to June 4, 2010, the collected data were analyzed. The findings of the study were as follows: The 57.3% of the teachers investigated provided toothbrushing guidance from time to time or couldn't do it at all. As for the reason why toothbrushing guidance was scarcely conducted, the largest group cited shortage of sinks(27.5%) as the reason, and the second biggest group replied they couldn't afford to pay attention to that due to heavy workload(20.6%). The third greatest group was pressed for time(16.7%). The teachers got a mean of 3.27 in oral health behavior, and 87.7% were concerned about children's oral health. The group of teachers who ever received oral health education was significantly better at oral health behavior and showed significant more interest in oral health(p<0.01). The 97.2% of the respondents considered oral health important. Concerning the reason, they replied it was crucial for systemic health (74.2%). The 89.4% of the teachers viewed child oral health education as necessary, and 86.5% had an intention to provide oral health education for children. They hoped to receive education on the oral health control act(4.52) and the prevention of dental caries(4.40). The above-mentioned findings confirmed that in order to step up the oral health promotion of child users of local children's centers, it's necessary to provide secondhand education for them through their teachers who have a great impact on them. Therefore the development of oral health education programs that cater to local children's center teachers is required.

• Clean Technology
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• v.28 no.1
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• pp.46-53
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• 2022

The agglomeration characteristics of coal and silica sand were investigated under various conditions using mixed samples consisting of coal, silica sand, and potassium hydroxide, which is an agglomeration accelerator. The samples were prepared by either physically mixing or using aqueous solutions. The experiments using the physically mixed powder samples were performed with a two hour reaction time. The results showed that the number of aggregates generated increased as the reaction temperature and the total potassium content increased. The experiments using aqueous solutions were performed at 880 ℃, which is the operating temperature of a fluidized bed boiler, and at 980 ℃, which assumes a local hot spot. The amount of agglomeration generated as the reaction time increased and the total potassium content increased was identified. In the experiment performed at 880 ℃, the amount of aggregate generated clearly increased with the reaction time, and in the experiment performed at 980 ℃, assuming a local hot spot, a large amount of aggregate was generated in a relatively short time. The aggregates became harder as the potassium content increased. When the total potassium content was less than 1.37 wt.%, the aggregates were weak at both temperatures and collapsed even with a slight impact. Additionally, the surface characteristics of the silica sand and ash aggregates were observed by SEM-EDS analysis. The analysis revealed a large amount of potassium at the bonding sites. This result indicates that there is a high possibility of aggregation in the form of a eutectic compound when the alkali component is increased.

• (The) Research of the performance art and culture
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• no.40
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• pp.111-136
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• 2020

Agricultural high schools are undergoing a change their name from the mid-1950s to the 2000s. Although it varies slightly depending on the case, it has been changed from 'rural forests' to 'agricultural farms' or 'agricultural industries' and 'life sciences high schools' in turn. In several aricultural high schools had managed Nongak Department(class), it's guarantees the continuity of Korea's traditional folk art. Examples include entertainment and farming in Honam region of Jeonju aricultural high School in North Jeolla Province, Geumsan aricultural high School in South Chungcheong Province, Gimcheon aricultural high School in North Gyeongsang Province. Therefore, the interpretation and significance of studies should follow. This method of Nongak education in modern school institutions is a new phenomenon in the history of Nongak after modern time, the emergence of a whole new pattern of professional entertainment Nongak after paving and Female-Nongak, as well as local traditional folk music. Education here was conducted in such a way that the best performers of the time were invited as guidance teachers among traditional folk artists. Thus, various local and professional music and entertainment were able to be promoted Apart from the social relations of delay, social progress, and economy, the education of farming and music, which consists of teachers and students in public schools, has provided an environment where unlimited freedom is allowed for art forms. In other words, the conditions for a new performance style experiment and creative fusion were met, and the foundation for the development of professional musical performers who had acquired individualized talents from previous generations was laid down in the context of the phenomenon of active stage music and theater performance of outstanding in the culture of Nongak. In other words, the Department of Agriculture and aricultural high school was a very free space compared to other communities' and economic community's agricultural music in social relationships bound by traditional cultural customs. This is why they have created a new style of performance through a new experiment and a different traditional performance repertoire, and their activities have led to a more stylistic expansion from traditional farming. More importantly, the figures who came across Agricultural Nongak department became the main experts of traditional Korean folk music nowdays. Thus, Nongak Department, operated by the Agriculture and Forestry High School, was a space where would give a very important meaning in terms of Nongak history.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.7
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• pp.915-929
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• 2023

Improvements in people's quality of life, diversification of leisure activities, and changes in population structure have led to an increase in the demand for tourism and an expansion of the diversification of tourism activities. In particular, for coastal cities where land and marine tourism elements coexist, various factors influence their tourism demands. Tourism requires the construction of infrastructure and content development according to the demand at the tourist destination. This study aims to improve the prediction accuracy and explore influencing factors through time series analysis of tourism scale using agent-based data. Basic local governments in the Busan area were examined, and the data used were the number of tourists and the amount of tourism consumption on a monthly basis. The univariate time series analysis, which is a deterministic model, was used along with the SARIMAX analysis to identify the influencing factor. The tourism consumption propensity, focusing on the consumption amount according to business types and the amount of mentions on SNS, was set as the influencing factor. The difference in accuracy (RMSE standard) between the time series models that did and did not consider COVID-19 was found to be very wide, ranging from 1.8 times to 32.7 times by region. Additionally, considering the influencing factor, the tourism consumption business type and SNS trends were found to significantly impact the number of tourists and the amount of tourism consumption. Therefore, to predict future demand, external influences as well as the tourists' consumption tendencies and interests in terms of local tourism must be considered. This study aimed to predict future tourism demand in a coastal city such as Busan and identify factors affecting tourism scale, thereby contributing to policy decision-making to prepare tourism demand in consideration of government tourism policies and tourism trends.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.41 no.4
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• pp.21-29
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• 2023

The Northern Song Dynasty, the heyday of cultural and artistic achievements, brought significant changes to the history of gardens in China. The developments and contemplations that had evolved during the previous Tang Dynasty became intertwined with literature, painting, and art, leading to garden being perceived as works of art. In particular, the emergence of Su Shi(蘇軾) that permeated literature and art during the Northern Song Dynasty, had an impact beyond individual garden creation, influencing the development of public gardens and the diversification of garden. His long exile periods served as an opportunity to understand and reflect the local culture and characteristics, influencing the development of the garden. This study focuses on the ideology of Su Shi(蘇軾) that managed various gardens, examining the relationship between his exlie life and ideology. To do so, the study examines the form of the literati's gardens managed by Su Shi(蘇軾), with a particular emphasis on the Baiheju(白鶴居) garden in Huizhou, revealing the following characteristics and values. First, Su Shi(蘇軾), who was proficient in the Three Houses: Confucianism, Buddhism, and Taoism, combined his philosophy and unique perspective techniques with the location and composition elements of Baiheju(白鶴居) to enjoy the landscape. Although the ancient residence has a simple form, it possesses expansiveness through the combination of internal and external views. The interior is designed to be perceived as a single space, but it allows overlapping experiences of space and simultaneous appreciation of different sceneries. On the other hand, the spatial layout incorporates a hierarchical order to establish a sense of order. Second, the garden reflects the local characteristics, featuring numerous tropical plants and presenting vibrant and contrasting colors with structures. The planting forms embrace the concept of "huosei seikou" (活色生香) to enhance the color harmoniously. Additionally, the garden incorporates the poet's spiritual world, projecting it onto the garden as a contemplative place for spiritual nourishment and exploration of the ideal realm. For the pursuit of serenity and profound contemplation, the selected plantings are simple yet distinctive, providing rhythm and depth to the garden space. Third, Baiheju(白鶴居) has undergone changes over the years, but fundamentally, the form and elements of the garden shaped by Su Shi(蘇軾)'s descendants persist, confirming its heritage value.

• Journal of Korean Society for Atmospheric Environment
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• v.34 no.1
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• pp.16-37
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• 2018

In this study, difference in chemical composition of $PM_{2.5}$ observed between the year 2013 and 2015 at six air quality intensive monitoring stations (Bangryenogdo (BR), Seoul (SL), Daejeon (DJ), Gwangju (GJ), Ulsan (US), and Jeju (JJ)) was investigated and the possible factors causing their difference were also discussed. $PM_{2.5}$, organic and elemental carbon (OC and EC), and water-soluble ionic species concentrations were observed on a hourly basis in the six stations. The difference in chemical composition by regions was examined based on emissions of gaseous criteria pollutants (CO, $SO_2$, and $NO_2$), meteorological parameters (wind speed, temperature, and relative humidity), and origins and transport pathways of air masses. For the years 2013 and 2014, annual average $PM_{2.5}$ was in the order of SL ($${\sim_=}DJ$$)>GJ>BR>US>JJ, but the highest concentration in 2015 was found at DJ, following by GJ ($${\sim_=}SJ$$)>BR>US>JJ. Similar patterns were found in $SO{_4}^{2-}$, $NO_3{^-}$, and $NH_4{^+}$. Lower $PM_{2.5}$ at SL than at DJ and GJ was resulted from low concentrations of secondary ionic species. Annual average concentrations of OC and EC by regions had no big difference among the years, but their patterns were distinct from the $PM_{2.5}$, $SO{_4}^{2-}$, $NO_3{^-}$, and $NH_4{^+}$ concentrations by regions. 4-day air mass backward trajectory calculations indicated that in the event of daily average $PM_{2.5}$ exceeding the monthly average values, >70% of the air masses reaching the all stations were coming from northeastern Chinese polluted regions, indicating the long-range transportation (LTP) was an important contributor to $PM_{2.5}$ and its chemical composition at the stations. Lower concentrations of secondary ionic species and $PM_{2.5}$ at SL in 2015 than those at DJ and GJ sites were due to the decrease in impact by LTP from polluted Chinese regions, rather than the difference in local emissions of criteria gas pollutants ($SO_2$, $NO_2$, and $NH_3$) among the SL, DJ, and GJ sites. The difference in annual average $SO{_4}^{2-}$ by regions was resulted from combination of the difference in local $SO_2$ emissions and chemical conversion of $SO_2$ to $SO{_4}^{2-}$, and LTP from China. However, the $SO{_4}^{2-}$ at the sites were more influenced by LTP than the formation by chemical transformation of locally emitted $SO_2$. The $NO_3{^-}$ increase was closely associated with the increase in local emissions of nitrogen oxides at four urban sites except for the BR and JJ, as well as the LTP with a small contribution. Among the meterological parameters (wind speed, temperature, and relative humidity), the ambient temperature was most important factor to control the variation of $PM_{2.5}$ and its major chemical components concentrations. In other words, as the average temperature increases, the $PM_{2.5}$, OC, EC, and $NO_3{^-}$ concentrations showed a decreasing tendency, especially with a prominent feature in $NO_3{^-}$. Results from a case study that examined the $PM_{2.5}$ and its major chemical data observed between February 19 and March 2, 2014 at the all stations suggest that ambient $SO{_4}^{2-}$ and $NO_3{^-}$ concentrations are not necessarily proportional to the concentrations of their precursor emissions because the rates at which they form and their gas/particle partitioning may be controlled by factors (e.g., long range transportation) other than the concentration of the precursor gases.