상대변위를 이용한 지반정수 인식

최상현(Choi Sanghyun),조국환(Cho Kookhwan) 한국철도학회 2005 한국철도학회 학술발표대회논문집 Vol.- No.-

In designing underground structure such as tunnels, estimating geotechnical characteristics of the ground is one of the most important and difficult tasks. In this paper, a methodology that can identify geotechnical parameters using only field-measured relative convergence displacements is presented. By using only relative convergence measurement data, inevitable errors in absolute convergence estimation can be avoided and in turn the parameter estimation process can be simplified. The methodology utilizes sensitivity relationship between static displacement measurements and geotechnical parameters. The feasibility and applicability of the proposed methodology is verified via a 3-d numerical example of a tunnel structure.

우리나라 출산율 저하의 원인과 그 대책

임국환(KookHwan Rhim),최만규(ManKyu Choi) 고려대학교 보건과학연구소 2005 보건과학논집 Vol.31 No.2

  A rapid and persistent decline of the birth rate in Korea began to occur in the early 1960s when the government enforced a five-year plan for economic development and a birth control policy for the declining rate. Recently, as a result, the total birth rate has declined to 1.19 which is the lowest level in the world according to the National Statistical Office. Fertility decline foreshadows serious social problems and a decrease in the national economic development such as the decline of economic activity population, the increase of the duty of supporting an aging population.<BR>  The aim of this study is first to examine the present situation and problems related to low fertility, and then to inquire into and discover the factors affecting the birth rate by comparing data from the 1970s to the recent trend of Korea"s precipitous drop in the birth rate.<BR>  As for the cause of the fertility decline, this study examined the marriage and delivery age of women, the divorce rate, and the birth sex ratio as a demographic factors, and GNI(gross national income), the proportion of women"s economic activity, the expense of bringing up children as a socio-economic factors. This study also analyzed the correlation between the birth rate and the relevant factors as the previous stage of the multiple regression analysis to discover the affects on the birth rate. As a result, the correlation among relevant factors, independent variables, was very high. So the stepwise multiple regression analysis(applied a reduced regression model) was performed to find out factors affecting the contin??uously decreasing the birth rate. As a result, the marriage age of women proved a negative factor affecting, statistically and significantly, the contin??uously decreasing total fertility in Korea. After all, a government supported policy and social circumstance are required to decrease women"s marriage age.

주 40시간 근무제도 도입에 따른 의료기관 종사자들의 직종별 인식도 비교

최만규(ManKyu Choi),이준협(JunHyup Lee),이준협(TaeRo Lee),이현실(HyunSill Rhee),임국환(KookHwan Rhim) 고려대학교 보건과학연구소 2004 보건과학논집 Vol.30 No.2

  Many foreign countries have made attempts to enhance working conditions for employees by reducing working hours, but it is true that Korea has focused more on economic growth rather than on the welfare of employees. However in the last few years, with increasing concern about quality of one"s life, the issue of working time reduction has become a controversial one. In July 2004 a law on working time reduction was made, and has been enforced in most work places, dependant upon the number of employees from which medical institutions should not be exempted.<BR>  This study was conducted to investigate the differences of opinion by job classification amongst employees of medical institutions. For the purpose of this study, a self-administerd questionnaire was conducted with 140 employees of 10 medical institutions located in Seoul andGyeonggi-Do province from August 1 to 7, 2004. The sample subjects  of this study consisted of 128(91.4%) employees who faithfully responded to the questionnaire and the major statistical methods included frequency, and chi-square test.<BR>  The major results of this study are as follows:<BR>  Firstly, about 90% of the respondents had knowledge of related contents of the 40 hours a week working time reduction. And the ratio of the respondents supporting introduction of working time reduction was 68.8%, and by job classification, more than half of medical doctors showed a contrary opinion, and about half of other groups such as nurses, medical technicians, administrative staffs were for it.<BR>  Secondly, the results of analyzing various factors that influence the quality of medical services and business performance is as follows: Medical doctors thought that the working time reduction would have a bad effect on the quality of medical services and business performance as a result of decreased patients. But other groups such as nurses, medical technicians, administrative staff presumed that the quality of medical services and business performance would not be changed but rather improved if strategies for operation were appropriately considered and performed.<BR>  Finally, the medical institutions preparing working time reduction need to make extra efforts to implement the system successfully such as making manpower operation more efficient, strengthening care capacity and function of emergency care centers, providing incentives for workers on Saturdays, improving the process of the working system and environment, fortifying weekday care, developing a weekend care program, and so on.

Impact of Crohn’s Disease on the Survival of Patients with Small-Bowel Adenocarcinoma in Korea: A Bicenter Cohort Study

Kim Kyuwon,Choi Kookhwan,Hwang Sung Wook,Im Jong Pil,Ye Byong Duk,Kim Joo Sung,Park Kyu Joo,Yang Suk-Kyun,Koh Seong-Joon,Park Sang Hyoung 거트앤리버 소화기연관학회협의회 2023 Gut and Liver Vol.17 No.4

Background/Aims: Owing to the low prevalence of small-bowel adenocarcinoma (SBA), data on the impact of Crohn’s disease (CD) on the survival of patients with SBA are lacking. Therefore, we investigated this issue in this study. Methods: In this bicenter cohort study, patients with histologically confirmed SBA were retrospectively enrolled and classified into two groups: sporadic SBA and CD-associated SBA. Patients with duodenal SBA were excluded. Overall survival, disease-free survival, and factors associated with survival were analyzed. Results: Of 128 patients with SBA, 115 had sporadic SBA and 13 had CD-associated SBA. Ileal involvement and poorly differentiated tumors were more common in the CD-associated SBA group than in the sporadic SBA group (ileal involvement, 53.8% vs 22.6%; poor differentiation, 46.2% vs 14.8%; both p<0.05). In survival analysis, overall survival showed no statistical difference between the sporadic SBA and CD-associated SBA groups (p=0.370). However, when stratified by stage, the adjusted overall survival of the CD-associated SBA group was lower in patients with an advanced disease stage (p=0.029). Disease-free survival showed the same tendency, albeit without clinical significance (p=0.097). CD (hazard ratio [HR], 2.308; p=0.047), older age (≥65 yr) at SBA diagnosis (HR, 2.766; p=0.001), and stage III/IV disease (HR, 3.151; p<0.001) were factors associated with mortality. Conclusions: The overall survival of patients with CD-associated SBA did not differ from that of patients with sporadic SBA. However, as CD is an independent risk factor for mortality, vigilant surveillance in high-risk patients may be crucial.

정신적 장애인의 건강수준과 노동시장 차별경험이 경제활동에 미치는 요인분석

박효은 ( Hyoeun Park ),임국환 ( Kookhwan Rhim ),최만규 ( Mankyu Choi ) 대한보건협회 2015 대한보건연구 Vol.41 No.2

Objective: The aim of the study was to analyze some factors determining economic activities of mentally ill people : First, the factors associated with sociology of population, health resources, and discrimination on labor``s market. Further, the research was to suggest practical and policy implications for boosting economic activities by people with mental disorders. Methods: The data were based on the 4th Panel Survey of Employment for the Disabled(2011) by Korea Employment Agency for the Disabled, including 346 mentally incapacitated people of a total of 5,092 subjects in the study. Logistic regression analysis was performed to examine the factors influencing employment status and those determined by type of disability. Results: The result of the study is as follows. Of 346 subjects of analysis, 64(18.2%) were economically active population, and 284(81.8%), not. In an integrated model, one of the most influencing factors for economic activities was experienced discrimination in job-seeking and employment. Additionally, it showed some favoring factors in economic activities for : those residing in medium-sized cities, those with larger households, those married, those in ``subjectively`` good health, and those independent of daily lives`` assistance. Conclusion: According to our analysis, through these results, some suggestions should be made as follows : Against the backdrop, business owners and colleagues should achieve a better understanding of people with psychological disorders and should take practical action against ``adverse selection`` for them. The government should implement policies to promote active employment of the mentally incapacitated and to support business owners with practical assistance.

The association between Alcohol Consumption Behavior and Mental Health in a Community in Seoul

Bohye Lee,Jinhee Kim,Mankyu Choi,Kookhwan Rhim 한국알코올과학회 2009 한국알코올과학회 학술대회 Vol.2009 No.1