• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.3
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• pp.46-53
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• 2009

Urbanization brings several changes to the natural environment. Its consequences can have a direct effect on climatic features, as in the Urban Heat Island Effect. One factor that directly affects the urban climate is the green area. In urban areas, vegetation is suppressed in order to accommodate manmade buildings and streets. In this paper we analyze the effect of green areas on the urban temperature in Seoul. The period selected for analysis was July 30th, 2007. The ground temperature was measured using Landsat TM satellite imagery. Land cover was calculated in terms of city area, water, bare soil, wet lands, grass lands, forest, and farmland. We extracted the surface temperature using the Linear Regression Model. Then, we did a regression analysis between air temperature at the Automatic Weather Station and surface temperature. Finally, we calculated the temperature decrease area and the population benefits from the green areas. Consequently, we determined that a green area with a radius of 500m will have a temperature reduction area of $67.33km^2$, in terms of urban area. This is 11.12% of Seoul's metropolitan area and 18.09% of the Seoul urban area. We can assume that about 1,892,000 people would be affected by this green area's temperature reduction. Also, we randomly chose 50 places to analysis a cross section of temperature reduction area. Temperature differences between the boundaries of green and urban areas are an average of $0.78^{\circ}C$. The highest temperature difference is $1.7^{\circ}C$, and the lowest temperature difference is $0.3^{\circ}C$. This study has demonstrated that we can understand how green areas truly affect air temperature.

• Radiation Oncology Journal
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• v.12 no.1
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• pp.27-31
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• 1994

There are a number of reports suggesting that there may be a correlation between the clinical response to radiotherapy in various tumors and the clonogenic survival of cell lines derived from these tumors following exposure to 2 Gy(SF2). Authors conducted this study to determine SF2 for cells in primary culture from surgical specimens. The tumor tissues with squamous cell carcinoma of uterine cervix and head and neck were obtained. The tumor tissues were disaggregated to single cells by incubating with collagenase type w for 2 hours with constant stirring. Single cell suspensions were inoculated in four 24-well plates precoated with cell adhesive matrix. After 24 hours of incubation at 37$ ^{\circ}C $, rows of four wells were then irradiated, consisting of control set and five other sets each receiving doses of 1,2,3,4, and 6 Gy. After incubation for a total of 13 days, the cultures were stained with crystal violet and survival at each dose was determined by quantitative image analysis system, To determine whether cell growth was of epithelial origin, immunocytochemical staining with a mixture of cytokeratin and epithelial monoclonal antibodies were performed on cell cultures. During the period of this study, we received 5 squamous cell carcinoma specimens of head and neck and 20 of uterine cervical carcinoma. Of these, 15 yielded enough cells for radiosensitivity testing. This resulted an overall success rate of 60$ \% $. The mean SF2 value for 15 tumours was 0.55$\pm$0.17 ranging from 0.20 to 0.79. These results indicate that there is a broad range of sensitivities to radiation in same histologic type. So with a large patient population, we plan to determine whether a different SF2 value is associated with tumours that are controlled with radiotherapy than those that are not.

• Journal of Preventive Medicine and Public Health
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• v.35 no.3
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• pp.245-254
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• 2002

Objective : To test if the intake of $H_2$ receptor antagonists ($H_2$-RAs) increases the risk of gastric cancer in the elderly. Methods : The source population for this study was drawn from the responders to a questionnaire survey administered to the Korea Elderly Pharmacoepidemiological Cohort (KEPEC), who were beneficiaries of the Korean Medical Insurance Corporation, were at least 65 years old, and residing in Busan in 1999. The information on $H_2$-RAs exposure was obtained from a drug prescription database compiled between inn. 1993 and Dec. 1994. The cases consisted of 76 gastric cancer patients, as confirmed from the KMIC claims data, the National Cancer Registry and the Busan Cancer Registry. The follow-up period was from Jan. 1993 to Dec. 1998. Cancer free controls were randomly selected by 1:4 individual matching, which took in to consideration the year of birth and gender. Information on confounders was collected by a mail questionnaire survey. The odds ratios, and their 95% confidence intervals, were calculated using a conditional logistic regression model. Results : After adjusting for a history of gastric ulcer symptoms, medication history, and body mass index, the adjusted OR (aOR) was 4.6 (95% CI=1.72-12.49). The odds ratio of long term use (more than 7 days) was 2.3 (95% CI=1.07-4.82). The odds ratio of short term use was 4.6 (95% CI=1.26-16.50). The odds ratio of parenteral use was 4.4 195% CI=1.16-17.05) and combination use between the oral and parenteral routes (aOR, 16.8; 95% CI=1.21-233.24) had the high risk of gastric cancer. The aOR of cimetidine was 1.7 (95% CI=1.04-2.95). The aOR of ranitidine was 2.0 (95% CI=1.21-3.40). The aOR of famotidine was 1.7 (95% CI=0.98-2.80). Conclusion : The intake of $H_2$-RAs might increase the risk of gastric cancer through achlorhydria in the elderly.

• Journal of Preventive Medicine and Public Health
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• v.37 no.4
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• pp.359-365
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• 2004

Objectives : This study was performed to determine whether an increase in abdominal obesity is an independent risk factor for impaired fasting glucose and type 2 DM. Methods : Among 24,212 adults over 30 years who undertook comprehensive medical screening examinations from Jan to Dec 1999, in a university hospital in Seoul, a total of 11,183 subjects were selected who had no DM at baseline and who were followed up more than once by Dec 2002. The average follow up period was 2.4 (${\pm}0.5$) years. DM was defined as having a fasting glucose level $\geq$ 126mg/dl, and impaired fasting glucose as showing a fasting glucose level between 110 and 125 mg/dl. Body weight, height and waist circumference (WC) were simultaneously measured with blood sampling. The relative risks (RRs) for DM and impaired fasting glucose by WC were calculated using Cox proportional hazard model. Ageadjusted rates were estimated by direct standardization using a reference population of 2000 from 30 to 80 years. Results : The average age of the subjects was 41.7 (${\pm}7.0$) years; males 41.2 (${\pm}6.5$) and females 45.6 (${\pm}9.2$). RRs for type 2 DM by WC with the reference group of WC < 80cm were as follows: 2.66 (95%, CI $0.55{\sim}12.8$) for WC of $80{\sim}89cm$ in men, 5.92 (95%, CI $1.08{\sim}32.3$) for WC $\geq$ 90 cm in men, and 2.64 (95%, CI $0.23{\sim}29.8$) for WC of $80{\sim}89cm$ in females. RRs for impaired fasting glucose by WC were 3.03 (95%, CI $2.18{\sim}4.22$) for WC $80{\sim}89cm$ in men, 6.10 (95%, CI $4.25{\sim}8.75$) for WC $\geq$ 90cm in men, and 1.56 (95%, CI $0.43{\sim}5.67$) for WC $80{\sim}89cm$ in women, and 8.08 (95%, CI $2.22{\sim}29.4$) for WC $\geq$ 90cm in females. These results remained significant after adjustment for age, BMI and fasting glucose concentrations at baseline in both sexes. Annual increment of more than 1 cm in WC was associated with the development of DM and impaired fasting glucose independently of age, sex, BMI, or presence of abdominal obesity. Conclusion : In Korean adults, abdominal obesity increased the risk for the development of type 2 diabetes and impaired fasting glucose. This result supports many other prospective studies suggesting abdominal obesity as a risk factor for type 2 diabetes.

• Journal of Preventive Medicine and Public Health
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• v.27 no.2 s.46
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• pp.337-365
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• 1994

Rubella is a viral disease with mild constitutional symptoms and generalized rashes. In childhood, it is an inconsequential illness, but when it occurs during early pregnant period, there are significant risks of heart defects, cataract, mental retardation to the fetus. The series of congenital defects induced by rubella is called 'congenital rubella syndrome'. Many research have been performed to find out more effective prevention program on rubella. The objectives of this study are, first, to calculate the incidence rate of acute rubella infection and congenital rubella syndrome in Korea, second, to evaluate economic efficiency of several rubella vaccination policies and to offer data for the most reasonable decision on vaccination policy. Study populations are 663,312 children of one year-old in 1992. The author has performed cost-benefit analyses according to the three vaccination policies-U.S.A.'s. U.K.'s and Sweden's. In this Study, the author got the incidence rate of acute rubella infection using the catalytic model. In the meantime, the author used 50 per 100,000 live births as the incidence rate of congenital rubella syndrome. The discount rate used in this study was 5 percent per annum. The sensitivity analyses were done with different discount rates (4%, 7%) and different incidence rate of congenital rubella syndrome (10,100 per 100,000 live births) : The study results are as follows: 1. Without vaccination, lifetime expenditures per patient for acute rubella infeciton amount to 14,822 won and the total expenditures to about 3.1 billion won. Meanwhile, lifetime expenditures per patient for congenital rubella syndrome amount to about 91 million won and the total expenditures to about 16.3 billion won without vaccination. 2. The cost of vaccination for a child of one year old was 2,322 won and the total cost for the one year old children was about 1.5 billion won (American style). The cost for vaccination of female children at fifteen was about 339 million won (Birtish style). And the cost of vaccination at one for both sex and female children at fifteen was about 1.9 billion won (Swedish style). 3. The benefit to cost ratios of vaccination of female children at fifteen that is the british mode of rubella vaccination, was 60.0 at the level of 80% population coverage and 48.6 at 100% coverage. It shows much higher benefit to cost ratio than those of the other two vaccination policies. 4. Both net benefits of vaccination at one (American style) and that of vaccinations at one and fifteen (Swedish style) range from about 17.0 billion to 17.8 billion won, those were larger than that of vaccinations of female children at fifteen (Birtish style, about 16.0 billion). 5. In marginal cost-benefit analysis of only additional program of revaccination, the benefit to cost ratios were 3.6 (80% coverage rate) or 0.6 (100% coverage rate). It implies that additional program was less efficient or inefficient. 6. In sensitivity analysis with different discount rates(4% or 7%) and different incidence rates of congenital rubella syndrome (10 or 100 per 100,000 live births), the benefit to cost ratios has fluctuated in wide range. However, all the ratios of vaccination of female children at fifteen were higher than those of the others. Even under the most conservative assumption, the benefit to cost ratios of all the rubella vaccination policies were higher than 3.3. In conclusion, all the rubella vaccination policies found to be cost-effective and particularly the vaccination of female children at fifteen was strongly recommended.

• Journal of the Korean Society of Radiology
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• v.9 no.6
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• pp.393-401
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• 2015

Radiation therapy for lung cancer is an effective treatment during monotherapy or combination therapy. Studies have reported that the optimum utilization rate of radiation therapy is estimated at 61% to 74%. Radiation therapy in Korea has been investigated to be low; further studies are needed. This study was intended to assess the appropriateness of the use of radiation and to reveal the use of radiation therapy-related factors by examining radiation therapy in lung cancer patients of Busan and South Gyeongnam Province. This study was aimed at the population diagnosed with lung cancer in Busan and South Gyeongnam Province. To conduct the study, 1036 patients enrolled in two hospitals were collected and 897 appropriate as subjects were selected. We compared the optimum utilization rate and actual rate of radiation therapy, and revealed the adequacy and related factors for use of radiotherapy. Of 897 patients, 503 (56%) were treated with medical therapy and 394 (44%) were given radiotherapy. The radiotherapy utilization rate of all lung cancer patients was 42%. The proportion of non-small cell lung cancer by histologic type was 33% and that of small cell lung cancer was 90%. Factors related to radiation therapy used in cancer were age, histological type, clinical stage, doctor refereed to, and clinical examination. Compared to radiation utilization by region (site), curative chest therapy was 42%; palliative treatment was 26%. In the comparison of histologic types, utilization of small-cell lung cancer is lower; the lowest especially in the stage III. Utilization of radiation therapy in Busan and South Gyeongnam Province was lower than the reasonable one. Utilization difference could be explained by patient factors, tumor factors, and health service factors. To improve utilization,development ofoutreach service programs and activation of the multidisciplinary team are required.

• Journal of Christian Education in Korea
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• v.62
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• pp.257-283
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• 2020

Our current society is experiencing a mass upheaval through globalization: mobility, hybridity, and cultural diversity are part of this world phenomenon. We can say that these changes are a result of people crossing borders due to international travel, immigration, emigration, studying abroad, labor, international marriages, fast and comfortable transportation, and the Internet. According to 2018 UNPD(Untied Nations Population Division)'s data, the international migrants have exceeded 258 million as of 2017. The increased number of migrants signifies that people with various backgrounds move from their own culture to a drastically different one. Interacting with different cultures can give people the chance to experience abundant lifestyles and improve life qualities. During that process, however, the differences between cultures can cause not only misunderstandings, conflicts, and violent collisions, but also xenophobia or radical nationalism. The current society is confronted with a problem: the people cannot stubbornly cling to a homogenous ethnicity anymore, which makes the coexistence between the citizens and immigrants necessary. Through these circumstances, I aim to suggest an educational model and a practical curriculum from a Christian perspective as the aim of this study. It seeks to encourage Christians to flexibly respond to these conflicts and collisions, and to fulfill their social responsibilities faithfully. For this reason, I will explore and seek sharing practical values through both shalom's communality as a theological approach and postconventionality in mature adults as a social-scientific approach. Consequently, I have few requests for the readers. First, approach with openness, understanding, and respect for other culture. Second, see this study as one step of confronting the global problem for coexistence and coprosperity of all social agents in the earth, a limited space. Third, notice that this study uses the interdisciplinary approach (theological and social scientific view) for a shareable, practical value that consistently leads the curriculum of my thesis, and a scientific method to eliminate bias. Lastly, understand that this study will eventually be used in educational practice, and as a result it prioritizes giving thought to the Christian educational environment. This study begins by exploring the conflicts and collisions between diverse cultures of our current society in international and national cases. Afterwards, I will reflect on how we can manage these conflicts and collisions by exploring the social-scientific view, postconventionality in mature adults, the theological view, and shalom's communality as a complement for the postconventionality's personal dimension. In conclusion, I suggest a curriculum that achieves peace as a practical value based on postventionality and shalom's communality for this study's goal.

• The Korean Journal of Air & Space Law and Policy
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• v.30 no.2
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• pp.3-36
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• 2015

As of end of 2014, the population engaging in aviation activities for leisure has reached approximately 13 million, where approximately 356 cases involve a general aircraft, 200 cases involve light aircraft, and 636 cases involve an ULM. The industry for leisure has become a very promising industry in line with rapidly rising living standards which are expected to further increase in the future. The demand for such services is expected to increase over time. The purpose of this paper is to review the development and site selection of airfields in anticipation of these developments in the industry. While the government also has experience in the review of airfield location and candidate sites, it is not the government that carries out the actual construction. As such, the feasibility of the site needs to be verified in terms of actual construction. This study identified factors for Site Selection of factors through a review of related documents and existing research reports. A questionnaire was also used to collect the views of experts in the field, which was then analyzed. The Research model was confirmed in the layered form for an AHP analysis. The factors for Site Selection were identified as the technical / operational factors and economic / political elements for a two-stage configuration. The third step consisted of technical and operational elements. The final step is was constructed a total of 11 elements (weather, surface conditions, obstacle limitation surface, airspace conditions, operating procedures, noise problems, environmental issues, availability of facilities, construction and investment costs, contribution to the local economy, accessibility, demand / the proximity of demand). The surveys are conducted for more than 10 General and light aircraft pilots, professionals, and instructor. The analysis results showed a higher level in the technical / operating elements (73.2%) in the first step, while the next step sawa higher level of the operational elements (30.9%) than the other. The factors for Site Selection were any particular elements did not appear high, the weather conditions (17.5%), noise problems (19.8%), the proximity of demand (6%), accessibility (5.7%), environmental issues (11.1%), availability of facilities (8%), airspace conditions (7.9%), obstacle limitation surface (12%), construction and investment costs (4.2%) and to operating procedures (4.9%), contribution to the local economy (3.8%).

• KDI Journal of Economic Policy
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• v.31 no.1
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• pp.105-138
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• 2009

Although the decline in fertility rate is generally observed along the history of economic development throughout the world, the continuing decline hitting below the replacement level in Korea over the recent years gathered serious social concerns on the ground that it accelerates the process of population aging. The total fertility rate in Koreareached 2.08 in 1983, and gradually fell to the levels of 1.08 in 2005 and 1.26 in 2007. The policy debate over the role of the government has been focused mainly on the level of theoretical discussion without substantial basis on firm empirical evidence and the determinants of fertility. The objective of the paper is to empirically investigate the fertility effect of the female wage, which is understood as one of the most important determinants of fertility in Koreasince 1980 focusing on one aspect of fertility, namely birth spacing. Using the Korean National Fertility Survey conducted in 2006, I estimate a duration model of first and second births taking into account individual heterogeneity, which turned out to be an important factor to control for. Compared with previous studies in the literature on the Korean fertility, the study has an advantage of using the complete pregnancy history of women in a more representative sample. Unlike the previous studies, the analysis also deals with the endogeneity of marriage by treating a certain age, rather than age at marriage, as the time in which a woman becomes exposed to the risk of pregnancy. The study shares the common problem in the literature on birth spacing of lacking relevant wage information for respondents in a retrospective survey. I estimate the wage series as a function of the basic characteristics using the annual Wage Structure Survey from 1980 to 2005, which is considered as a nationally representative sample for wage information of employees. The results suggest that the increase in female wage by 10 percent leads to a decrease in second birth hazard by 0.56~0.92 percentage points and that the increase in spouse's wage by the equal amount is accompanied by the increase in second birth hazard by 0.36~1.13 percentage points. These estimates are more precisely estimated and of smaller magnitude than those presented by the previous studies. The results are robust to the different specifications of the wage equation. The simulation analysis based on the predicted values shows that about 17% of the change in the second birth hazard over the period 1980 to 2005 was due to the change in the female wage. Although there is some limitation in data, the results can be viewed as one estimate of the role of female wage on the recent fertility decline in Korea. The question raised by the paper is not a normative one of whether a government should promote childbearing but a positive one thatexplains fertility decline. Therefore, if there is a wide consensus on promoting childbearing, the finding suggests that the policies designed to reduce the opportunity cost of women in the labor market would be effective. The recent movement of implementing a wide range of family-friendly policies including child care support, maternity leave, parental leave and tax benefit in developed countries should be understood in this context.

• Journal of dental hygiene science
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• v.17 no.6
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• pp.487-494
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• 2017

There is little evidence on the effects of environmental tobacco smoke (ETS) on prevalence of periodontal disease. The aims of this study were to explore the trends of prevalence of periodontal disease and types of exposure to smoke, including ETS according to the survey year, identify factors affecting periodontal disease, and compare the effect size of periodontal disease between active smokers and secondhand smokers. Data on 11,643 individuals were obtained from the fourth and fifth Korean National Health and Nutritional Examination Surveys. Information on exposure to ETS at home and work was self-reported. Severity of periodontal disease was evaluated using the community periodontal index. A multivariate logistic regression analysis was performed to model periodontal disease using types of smoking and the survey year. Overall, the prevalence of periodontal disease was 26.0% (n=3,029) and about 9% of the study population were secondhand smokers. The prevalence of periodontal disease among smokers was significantly increased according to smoking types by year. Active smokers showed a statistically significant adjusted odds ratio (aOR) for having periodontal disease except in the year 2007, whereas secondhand smokers had significant associations only in 2010 (aOR, 1.68; 95% confidence interval, 1.05 to 2.70) compared to non-smokers. For secondhand smokers, the statistical relationship of predicting periodontal disease was weaker than that of active smokers. However, ETS should separately be considered as an important risk factor for periodontal disease. This study suggested the need for further investigation of the impact of ETS on prevalence of periodontal disease using in-depth research designs and objective measurements for assessing periodontal disease and ETS.