• Nuclear Engineering and Technology
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• 제21권3호
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• pp.171-185
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• 1989

유연탄 발전과 원자력 발전의 경제성 평가를 균등한 인체 위험도 하에서 서기 2000년의 시점에서 수행하였다. 유연탄 발전과 원자력 발전의 인체에 대한 영향 비교에서, 유연탄의 영향이 원자력에 비해서 10배가량 높은 것을 에너지 시스템의 위험도 평가에 관한 여러 연구결과들로부터 알 수 있었다. 그런데 위험도가 0인 상태는 존재하지 않으므로, 유연탄 발전과 원자력 발전간의 위험도 차이만을 본 논문의 위험도로 간주했다. 인체 위험도 비용은 사망과 질병의 두 경우로 나누어서, 사망의 경우에는 Human Life Value로 계산하고, 질병의 경우에는 완치될 때까지의 치료비등 제반 비용으로 계산했다. 이러한 방법에 의한 계산 결과 사망의 비용은 ＄250,000이 되었고, 질병의 경우는 ＄90,000이 되었다. (1986 US＄) 그리고 비용편익분석을 통해서 유연탄 화력 발전의 최적 규제 기준치를 구했는데, 이 규제치는 최소 사회비용이 발생되는 지점에서 구해졌다. 서기 2000년의 한국에서의 SOx에 대한 최적 규제치는 165ppm으로 나타났다. 이러한 전력 생산의 경제성 평가 방법으로부터, 원자력이 유연탄 화력에 비해서 더 경제적인 것으로 나타났다. 반면에 불확실도는 유연탄화력이 더 작은 것으로 나타났다.

• 한국식품영양학회지
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• 제12권3호
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• pp.279-289
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• 1999

This study was conducted to investigate the physical characteristics and risk factors for hyperchol-esterolemia (HC) in Korean. 344 adult men who took the annual health check-ups at D or J hospitals were participated in this cross-sectional study. The subjects were grouped by plasma total cholesterol level in to three groups: normal cholesterolemic (n=139) borderline hypercholesterolemic(n=93) and hypercholesterolemic (n=112) groups. The data of height weight and plasma cholesterol level were col-lected from medical records. Body circumferences(midarm, waist, hip, and thight) skinfold thicknesses (biceps, triceps, subcostal, abdomen, and suprailic), and body composition (fat mass and fat free mass) were measured. Body mass index (BMI) height/weight ratio (HWR) waist/hip circumference ratio (WHR) waist/ thigh circumference ratio (WTR) central skinfold thickenss (CSF) and peripheral skin-fold thickness were calculated. The subjects with HC had significantly higher weight BMI waist cir-cumference skinfold thickness and body fat mass than those of the normal subjects. The relative and attributable risks on HC were 1.61 and 0.17 for obesity (BMI$\geq$25) 1,30 and 0.11 for upper body obesity (WTR$\geq$1.30) and 1.54 and 0.18 for central body obesity (CSF$\geq$95.7). Plasma total cholesterol level was positively correlated with several antropometric parameters: BMI (p<0.001) weight(p<0.001) waist circumference(p<0.001) and skinfold thickness of abdomen (p<0.001) spraillic (p<0.01) triceps(p<0.01) subcostal (p<0.01) and biceps (p<0.05) In conclusion the major influencing factors to plasma cholesterol level was BMI. Among the each physical parameters the circumference of waist the skinfol-d thickness of abdomen and the percentage of body fat were closely related to plasma cholesterol level. The important risk factor for hypercholesterolemia was obesity specially upper body obesity and central body obesity.

• Journal of the Korean Data and Information Science Society
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• 제27권5호
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• pp.1193-1201
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• 2016

공간 또는 시공간 데이터에서 다른 지역에 비해 유난히 높은 위험률을 보이는 소위 핫 스팟 (hot spot)으로 불리는 클러스터 (cluster)를 찾으려고 하는 경우가 많다. 기존의 많은 방법들은 이러한 클러스터 패턴이 존재하는지에 대한 해답만 주었지만, 최근의 많은 방법들은 클러스터의 위치, 모양, 크기뿐만 아니라 찾아진 클러스터가 통계적으로 유의한지까지 검정해준다. 본 논문에서는 이러한 다양한 방법 중 가장 많이 사용되는 클러스터 탐색 방법 중 하나인 스캔 통계량을 이용한 방법을 소개하고 그 방법이 구현된 무료 소프트웨어 SaTScan을 이용한 결과를 보여주고 장단점을 논하고자 한다. 미국 국립암센터의 SEER 프로그램에서 제공하는 미국의 각 카운티별 암 사망자 자료 중 2006년 여성 폐암 사망자 데이터를 예시 데이터로 사용하여 스캔 통계량을 이용하여 구한 클러스터 탐색 결과를 제시하고 비슷한 연구를 하고자는 연구자에게 도움을 주고자 한다.

• International Journal of Oral Biology
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• 제42권4호
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• pp.163-168
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• 2017

Osteoporosis is a metabolic bone disease that is characterized by low bone mass resulting from an increase in bone resorption relative to bone formation. The most current therapies for osteoporosis have focused on inhibiting bone resorption by osteoclasts. The purpose of this study is to develop new anabolic agents for treatment of osteoporosis that have fewer risks compared to conventional therapies. We searched the natural products that were derived from the traditional Asian medicines which have been used for treatment of bone related diseases. Icaritin is a flavonoid glycoside derived from the herb Epimedium which has beneficial effects on bone formation. To determine the effect of icaritin on bone formation, we examined the effect of icaritin on MC3T3-E1 cell proliferation and differentiation. For determining the effects of icaritin on proliferation, we performed the MTT assay using MC3T3-E1 cells. To evaluate whether icaritin could promote the osteogenic differentiation of MC3T3-E1 cells, alkaline phosphatase (ALP) activity and mRNA expressions of Runx2, osteocalcin (OCN), RANKL, and osteoprotegerin (OPG) were determined. Icaritin increased MC3T3-E1 cell proliferation. Icaritin increased the ALP activity of MC3T3-E1 cells on 72 hour culture in osteogenic media. mRNA expression of Runx2 was increased after 24 hour culture with icaritin. mRNA expression of osteocalcin was increased after 72 hour culture with icaritin. In addition, icaritin increased the mRNA expressions of OPG and RANKL. However, icaritin increased the mRNA expression of OPG much more than that of RANKL, and then, it increased the OPG/RANKL ratio. These results suggest that icaritin promotes osteogenic differentiation of osteoblasts and decreases osteoclast formation regulated by osteoblasts.

• 한국환경보건학회지
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• 제35권1호
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• pp.1-10
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• 2009

This study assessed the relationships between levels of $PM_{10}$ and hospitalization rates for asthma among children from 2003 to 2005 at four major cities in Korea. In addition, we estimated the reduced number of asthma hospitalization associated with an ambient $PM_{10}$ improvement to the acceptable levels as recommended by the World Health Organization (WHO). The Generalized Additive Model (GAM) was used to estimate the relative risks (RR) of asthma hospitalization associated with changes in $PM_{10}$ The RRs of children's asthma hospitalization for every $10{\mu}g/m^3$ increment in $PM_{10}$ were 1.009(95% CI = 1.004-1.014) in Seoul, 1.013(95% CI = 1.006-1.021) in Incheon, 1.009(95% CI = 1.002-1.016) in Busan, and 1.021(95% CI = 1.005-1.037) in Ulsan. We assessed $PM_{10}$ related health benefits from implementing the WHO's guidelines (24-hour average $50{\mu}g/m^3$) using the U.S. Environmental Protection Agency's Environmental Benefits Mapping and Analysis Program. The estimated benefits were 439(95% CI = 216-666) reduced asthma hospitalization in Seoul, 720(95% CI = 304-1,151) in Incheon, 260(95% CI = 66-459) in Busan, and 126(95% CI = 30-228) in Ulsan. It was concluded that improving $PM_{10}$ condition to the WHO guideline would make a significant contribution to the reduction in asthma hospitalization among children. Therefore, public health measures are still needed to improve air quality in Korea.

• Steel and Composite Structures
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• 제22권3호
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• pp.537-565
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• 2016

Australian railway networks possess a large amount of aging timber components and need to replace them in excess of 280 thousands $m^3$ per year. The relatively high turnover of timber sleepers (crossties in a plain track), bearers (skeleton ties in a turnout), and transoms (bridge cross beams) is responsible for producing greenhouse gas emissions 6 times greater than an equivalent reinforced concrete counterparts. This paper presents an innovative solution for the replacement of aging timber transoms installed on existing railway bridges along with the incorporation of a continuous walkway platform, which is proven to provide environmental, safety and financial benefits. Recent developments for alternative composite materials to replace timber components in railway infrastructure construction and maintenance demonstrate some compatibility issues with track stiffness as well as structural and geometrical track systems. Structural concrete are generally used for new railway bridges where the comparatively thicker and heavier fixed slab track systems can be accommodated. This study firstly demonstrates a novel and resilient alterative by incorporating steel-concrete composite slab theory and combines the capabilities of being precast and modulated, in order to reduce the depth, weight and required installation time relative to conventional concrete direct-fixation track slab systems. Clear benefits of the new steel-concrete composites are the maintainability and constructability, especially for existing railway bridges (or brown fields). Critical considerations in the design and finite element modelling for performance benchmarking of composite structures and their failure modes are highlighted in this paper, altogether with risks, compatibilities and compliances.

• Journal of Preventive Medicine and Public Health
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• 제40권4호
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• pp.321-328
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• 2007

Objectives : The aim of this study was to evaluate the roles of cigarette smoking, alcohol consumption, tuberculosis, and their interactions in the risk of lung cancer in a Korean cohort. Methods : The study subjects comprised 13,150 males and females aged above 20 years old. During the follow up period from 1993 to 2002, 79 lung cancer cases were identified by the central cancer registry and the national death certificate database. Information on cigarette smoking, alcohol consumption and the history of physician-diagnosed tuberculosis was obtained by interview. Indirect chest X-ray findings were also evaluated to ascertain tuberculosis cases. Cox proportional hazard models were used to estimate relative risks (RR) and 95% confidence intervals (CI) after adjusting for age and gender. Results : Cigarette smoking was statistically significantly associated with an increased risk of lung cancer [for current smokers, RR = 2.33 (95% CI = 1.23 - 4.42) compared to non-smokers]. After further adjustment for cigarette smoking, both alcohol consumption and tuberculosis showed no statistically significant association with the risk of lung cancer [for current drinkers, RR = 0.80 (95% CI = 0.48 - 1.33) compared to non-drinkers] [for tuberculosis cases, RR = 1.17 (95% CI = 0.58 - 2.36) compared to non-cases]. There was no statistically significant interaction between cigarette smoking and alcohol consumption (p-interaction = 0.38), or cigarette smoking and tuberculosis (p-interaction = 0.74). Conclusions : Although cigarette smoking was confirmed as a risk factor of lung cancer in this cohort study, this study suggests that alcohol consumption and tuberculosis may not be associated with the risk of lung cancer.

• 한국식품영양과학회지
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• 제28권3호
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• pp.710-721
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• 1999

This study was conducted to investigate the hematological characteristics and risk factors of hypercholesterolemia(HC) in Korean. 344 adult men who took the annual health check ups at D or J hospitals were participated in this cross sectional study. The subjects were grouped by plasma total cholesterol level into three groups: normal cholesterolemic(n=139), borderline hypercholesterolemic (n=93) and hypercholesterolemic(n=112) groups. The data of systolic and diastolic blood pressure (SBP/DBP), hemoglobin, plasma glucose, albumin and cholesterol levels were collected from medical records. The levels of plasma triglyceride(TG), HDL C, phospholipid, insulin, apo A and apo B were measured. The levels of plasma LDL C, VLDL C and atherogenic index(AI) were calculated. The subjects with HC had significantly higher SBP and DBP, albumin, TG, phospholipid, HDL C, LDL C, VLDL C and apo B level than those of the normal subjects. The relative and attributable risks on HC were 1.59 and 0.18 for hypertension(SBP/DBP$\geq$160/95), 2.08 and 0.35 for hypertriglyceridemia (TG $\geq$400mg/dl). Plasma total cholesterol level was positively correlated with several hematologic parameters: age(r=0.1242, p<0.05), DBP(r=0.1194, p<0.05), albumin(r=0.2029, p<0.001), plasma TG(r= 0.3829, p<0.001), phospholipid(r=0.6036, p<0.001), LDL C(r=0.8572, p<0.001), HDL C(r=0.2399, p< 0.001), AI(r=0.3116, p<0.001), apo B(r=0.2602, p<0.05) and Lp(a)(r=0.1372, p<0.05). However, plasma total cholesterol level was negatively correlated with the levels of Apo A1(r= 0.2922, p<0.001), and ABR(r= 0.3598, p<0.001).

• The Korean Journal of Pain
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• 제33권3호
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• pp.267-274
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• 2020

Background: General anesthesia (GA) has been considered the anesthetic technique which most frequent leads to phantom limb pain (PLP) after a limb amputation. However, these prior reports were limited by small sample sizes. The aims of this study were to evaluate the incidence of PLP according to the various anesthetic techniques used for limb amputation and also to compare the occurrence of PLP according to amputation etiology using the Korean Health Insurance Review and Assessment Service for large-scale demographic information. Methods: The claims of patients who underwent limb amputation were reviewed by analyzing the codes used to classify standardized medical behaviors. The patients were categorized into three groups-GA, neuraxial anesthesia (NA), and peripheral nerve block (PNB)-in accordance with the anesthetic technique. The recorded diagnosis was confirmed using the diagnostic codes for PLP registered within one year after the limb amputation. Results: Finally, 7,613 individuals were analyzed. According to the recorded diagnoses, 362 patients (4.8%) developed PLP after amputation. Among the 2,992 patients exposed to GA, 191 (6.4%) were diagnosed with PLP, whereas 121 (4.3%) of the 2,840 patients anesthetized with NA, and 50 (2.8%) of the 1,781 patients anesthetized under PNB developed PLP. The relative risks were 0.67 (95% confidence interval [CI], 0.53-0.84; P < 0.001) for NA and 0.43 (95% CI, 0.32-0.59; P < 0.001) for PNB. Conclusions: In this retrospective cohort study, using large-scale population-based databases, the incidence rates of PLP after limb amputations were, in the order of frequency, GA, NA, and PNB.

• Journal of Preventive Medicine and Public Health
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• 제39권1호
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• pp.81-86
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• 2006

Background: A number of studies have reported associations between the ambient air pollution concentrations and various health outcomes. Especially, ozone is well known for primary risk factor of asthma attacks. The results of a recent study indicate that the size of the effect on health outcomes due to air pollution varied according to several conditions, including age, gender, race and the socioeconomic status. Therefore, this study was conducted to examine the associations of ozone with the childhood asthma hospitalizations as stratified by the socioeconomic status (SES) at the community level in Seoul, Korea, 2002. Methods: SES at aggregated levels was measured on the basis of average regional health-insurance rate per citizen in the area. We applied the generalized additive model to analyze the effect of ozone on asthma after controlling for the potential confounding variables that were capable of influencing the results. Results: Our analysis showed that the number of children who were hospitalized for asthma increased as the SES of the residence area decreased. The estimated relative risks of hospitalization for asthma, as stratified by the SES of the community level, were 1.12 (95% confidence interval 1.00-1.25) in districts with the highest SES levels, 1.24 (95% CI=1.08-1.43) within the moderate SES levels, and 1.32 (95% CI=1.11-1.58) in the districts with the lowest SES levels. Conclusions: Our analysis showed that exposure to air pollution did not equally affect the health status of individuals. This suggests that not only the biological-sensitivity markers, but also the SES of the subjects should be considered as potentially confounding factors.