• 응용통계연구
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• 제18권1호
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• pp.27-41
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• 2005

『전국 장내 기생충 감염실태조사』를 위해 새로운 표본설계를 하였다. 2000년 인구 주택총조사의 10% 표본조사자료를 조사모집단으로 사용하였고, 조사의 특성상 각종 기생충의 감염율이 아주 낮은 관계로 통상적인 분석방법 대신에 상대위험도과 오즈비를 사용하였다. 표본배정은 네이만 배정의 절충형을 사용하였다. 또한 전국 단위와 특성별 추정이 가능하도록 하였고 추정의 정확성을 측정하기 위해 추정량의 분산식을 유도하였다.

• Journal of Preventive Medicine and Public Health
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• 제40권6호
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• pp.431-438
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• 2007

Objectives : The aim of this study is to summarize the current conditions and implications of health inequalities in South Korea. Methods : Through a literature review of empirical studies and supplementary analysis of the data presented in the 1998, 2001, and 2005 KNHANEs, we evaluated the extent and trends of socioeconomic inequalities in both health risk factors, such as smoking, physical activity, and obesity, and outcomes, such as total mortality, subjective poor health status by self-reports and metabolic syndrome. Relative risks and odds ratios were used to measure differences across socioeconomic groups, and the relative index of inequality was used to evaluate the changes in inequalities over time. Results : We found clear inequalities to various degrees?in most health indicators. While little change was observed in mortality differences over time, the socioeconomic gaps in risk factors and morbidity have been widening, with much larger differences among the younger population. Conclusions : Socioeconomic inequalities are pervasive across various health indicators, and some of them are increasing. The trends in socioeconomic inequalities in health should be carefully monitored, and comprehensive measures to alleviate health inequalities are needed, especially for young populations.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 1998년도 Advances in Ginseng Research - Proceedings of the 7th International Symposium on Ginseng -
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• pp.174-181
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• 1998

A prospective study was conducted to evaluate the preventive effect of Korean ginseng against cancer in the population residing ginseng cultivation area, Kangwha-eup from August 1987 to December 1997. The participants consisted of 4,553 adults over 40 years old who completed a questionare on ginseng intake. During the surveillance period, 14.4% (656 of 4,553) of subjects had died, cancer accounting for 23.9% (157) of total deaths. The proportional hazard model of Cox was used to estimate relative risks when controlling simultaneously for covariates. Ginseng intakers had a decreased risk (relative risk(RR) =0.48, 95% confidence interval (Cl) : 0.34-0.66) for cancer compared with non-intakers. The RRs of cancer were 0.36 (95% Cl: 0.24-0.56) for multiple combination intakers. Among 24 red ginseng intakers, there were no cancer deaths. The RRs of ginseng intakers were 0.38 (95% Cl: 0.20-0.71) in gastric cancer and 0.29 (95% Cl: 0.15- 0.57) in lung cancer. These findings strongly suggested Korean ginseng have non-organ specific cancer preventive effects against cancer. Further research for clarifying the mechanisms of prevention and clinical trials on Korean ginseng must be conducted with worldwide collaborations

• 아태비즈니스연구
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• 제11권3호
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• pp.21-46
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• 2020

Purpose - This study aims to find if the introduction of project finance perspective leads to any modification to the view of PM industry on CSFs of PPP and their relative importance rank. Design/methodology/approach - Through literature reviews, this study came up with a set of CSFs reflective of both perspectives. AHP method was applied for analysis by developing an Analytic Hierarchical Model from this set and survey questionnaires of pairwise comparison to solicit 46 qualified expert responses. Findings - This study concurs with PM industry to acknowledge 'risk allocation', 'legal framework' and 'quality of feasibility' as ones of most important CSFs. However, relative importance rank of individual CSFs goes through significant modification under this study in favor of 'sponsor commitment and quality' but against 'political environment', in particular. Research implications or Originality - Discussions on the CSFs led by PM industry have not been properly reflective of project finance perspective, which is injected into this study to cure the partiality. For researchers, findings of this study may call attention to financing perspective when they discuss CSFs of PPP. Practitioners may benefit from this study by allocating resources in view of this new finding when pursuing PPP projects.

• Communications for Statistical Applications and Methods
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• 제29권3호
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• pp.287-299
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• 2022

In radiation epidemiology, the excess relative risk (ERR) model is used to determine the dose-response relationship. In general, the dose-response relationship for the ERR model is assumed to be linear, linear-quadratic, linear-threshold, quadratic, and so on. However, since none of these functions dominate other functions for expressing the dose-response relationship, a Bayesian semiparametric method using splines has recently been proposed. Thus, we improve the Bayesian semiparametric method for the selection of the tuning parameters for splines as the number and location of knots using a Bayesian knot selection method. Equally spaced knots cannot capture the characteristic of radiation exposed dose distribution which is highly skewed in general. Therefore, we propose a nonparametric Bayesian knot selection method based on a Dirichlet process mixture model. Inference of the spline coefficients after obtaining the number and location of knots is performed in the Bayesian framework. We apply this approach to the life span study cohort data from the radiation effects research foundation in Japan, and the results illustrate that the proposed method provides competitive curve estimates for the dose-response curve and relatively stable credible intervals for the curve.

• Geomechanics and Engineering
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• 제30권5호
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• pp.479-487
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• 2022

This study evaluates the performance of gravel impact compaction piers system (GICPs) in strengthening retrofitting a very loose silty sand layer with a very high liquefaction risk with a thickness of 3.5 meters in a multilayer coastal soil located in Bushehr, Iran. The liquefiable sandy soil layer was located on clay layers with moderate to very stiff relative consistency. Implementation of gravel impact compaction piers is a new generation of aggregate piers. After technical and economic evaluation of the site plan, out of 3 experimental distances of 1.8, 2 and 2.2 meters between compaction piers, the distance of 2.2 meters was selected as a winning option and the northern ring of the site was implemented with 1250 gravel impact compaction piers. Based on the results of the standard penetration test in the matrix soil around the piers showed that the amount of (N₁)₆₀ in compacted soils was in the range of 20-27 and on average 14 times the amount of (1-3) in the initial soil. Also, the relative density of the initial soil was increased from 25% to 63% after soil improvement. Also the safety factor of the improved soil is 1.5-1.7 times the minimum required according to the two risk levels in the design.

• 수산해양기술연구
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• 제45권2호
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• pp.106-113
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• 2009

For the safety and cost reduction in the navigation, the automatic and intelligent system has been developed for the vessel, and the most important factor in the system is to decide the collision risk exactly. In this paper, we propose an advanced collision risk decision system for collision avoidance of the system. The conventional researches using DCPA and TCPA for calculating the collision risk have a problem to produce a same collision risk regardless of bearings for the ships, if they are located in the same distance from own ship. To solve this problem, in addition to DCPA and TCPA, we introduce the factor of VCD(variation of compass degree) and constant, CR which derived from COLREG'72(International Regulation for Preventing Collision at Sea, 1972) for evaluating the collision risk including even the burden of own ship navigator due to the encountering angle of each vessels. We decided the collision risk legally by the rule considering the relative situation of vessels. And therefore, the proposed system has two advantages, of which one is to produce more detail collision risk and another is to reflect the real underway situation in conformity with the rule.

• Asian Pacific Journal of Cancer Prevention
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• 제17권8호
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• pp.3759-3762
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• 2016

Background: Breast cancer risk assessment is a helpful method for estimating development of breast cancer at the population level. Materials and Methods: In this cross-sectional study, participants consisted of a group of 3,847 volunteers ($mean{\pm}SD$ age: $463{\pm}7.59$ years) in a convenience sample of women referred to health centers affiliated to Tehran University of Medical Sciences in Tehran, Iran. The risk of breast cancer was estimated by applying the National Cancer Institute's online version of the Gail Risk Assessment Tool. Results: Some 24.9% of women reported having one first-degree female relative with breast cancer, with 8.05% of them having two or more first-degree relatives with breast cancer. The mean five-year risk of breast cancer for all participants was $1.61{\pm}0.73%$, and 9.36% of them had a five-year risk of breast cancer >1.66%. The mean lifetime risk of breast cancer was $11.7{\pm}3.91%$. Conclusions: The Gail model is useful for assessing probability of breast cancer in Iranian women. Based on the their breast cancer risk, women may decide to accept further screening services.

• Journal of Community Nutrition
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• 제6권3호
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• pp.131-136
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• 2004

The purpose of this study is to compare the relative risk of metabolic syndrome (MS) in middle aged adults with different body weights. 155 subjects living in urban Beijing were recruited from 24 neighborhood committees of urban Beijing. They were divided into normal weight, overweight and obese groups according to their BMIs. The general information of the subjects was collected using an interview-administered questionnaire. Standard procedure was followed to measure subject's weight, height and waist. Biochemical parameters (total cholesterol (TC), low- and high­density lipoprotein cholesterol (LDL-C ; HDL-C), triglyceride (TG), and fasting glucose) and blood pressure were also determined. The results indicated that the systolic and diastolic blood pressure, HDL-C of obese group was lower than that of the normal weight group. Fasting glucose of obese males was significantly higher than that of normal weight males. No significant difference of fasting glucose was found among female groups. No significant difference of TG was found among male groups, while TG of overweight and obese females was both significantly higher than normal weight females. There was no significant difference of TC and LDL-C among normal weight, overweight and obese groups in both males and females. The MS rate of obese males was significantly higher than the normal weight and overweight males, as was the female. The relative risk of MS in obese group was about 11 times higher (OR=11.249, $95\%CI$ = 3.812 - 33.191) than the normal weight group after adjusting for age, gender, smoking, drinking, family economic level and education status. It is concluded that obesity contributed to lower HDL-C, hypertriglyceride, hypertension and MS after controlling the effects of age, gender, socioeconomic status, alcohol drinking and smoking. Obese individuals have a higher risk of having MS than their normal weight counterparts.

• 한국입자에어로졸학회지
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• 제20권2호
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• pp.25-33
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• 2024

Suspension of particulate matter (PM) in indoor spaces, which increases risk of negative impact on occupants' health from exposure to PM, is influenced by humidity level in the indoor environment. The goal of this study is to investigate the property of size-resolved PM suspension in accordance with the relative humidity through simulation chamber experiments which reflect the indoor environmental characteristics. The relative humidity of simulation chamber is adjusted to 35%, 55% and 75% by placing it inside a real-size environmental chamber which allows artificial control of climatic conditions (e.g., temperature, humidity). At the respective humidity conditions, PM suspension concentration caused by occupant walking is analyzed by particle size (0.5-0.8, 0.8-1.0, 1.0-2.5, 2.5-3.5, 3.5-4.5, 4.5-5.5, 5.5-8.0, and 8.0-10 ㎛). Irrespective of the particle size, the suspension concentration reveals a decreasing tendency as the relative humidity increases. Furthermore, a one-way analysis of variance (one-way ANOVA) test statistically verifies that the suspension concentration has a significant difference depending on the indoor relative humidity level. In addition, as the relative humidity increases, a proportion of the suspended particles with 0.5-2.5 ㎛ diameter decreases, while that with 2.5-3.5 ㎛ diameter increases. The reason is considered that the humidity has an effect on adhesion and coagulation forces of the particles.