오픈형 충전 해압 및 밸브의 유체 거동 분석을 위한 전산 수치해석

강대희,이효원,이승주,김원태 한국기계기술학회 2022 한국기계기술학회지 Vol.24 No.2

Valves are one of the indispensable components in modern industry. Filling and de-pressure connectors in rocket valves used for space launch vehicles are very important parts for smooth fluid supply. For this reason, an optimized design that can improve efficiency, miniaturization, weight reduction, and safety of the valve at the same time is required. In this work, flow analysis and structural analysis were performed through 3D modeling using computational numerical analysis for open type filling and de-pressure valves. As results, the flow velocity and pressure distribution of the fluid were analyzed through the flow analysis of valve, and stress distribution was conducted in structural analysis. Through this study, it is consequently expected to provide valves of various specifications by performing production and performance test evaluation of development prototypes.

사무실 근로자들에서의 sick building syndrome

강대희 大韓産業醫學會 1996 대한직업환경의학회지 Vol.8 No.3

A cross-sectional study was conducted to evaluate the relationship between sick building syndrome (SBS) and the factors affecting SBS among 90 office workers. The study consisted of 1) a review of previous environmental investigations, 2) measurement of CO₂, temperature, and relative humidity (RH), 3) a questionnaire survey of symptom prevalence and perception of environmental conditions using the National Institute for Occupational Safety and Health Indoor Air Quality (NIOSH IAQ) questionnaire, and 4) confidential interview and a review of medical records of employees having respiratory symptoms. CO₂, temperature, and RH measured on the day of questionnaire survey were within the recommended range by American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE). Sixty-six percent of respondents were women and 60% considered their job description either "managerial(28%)" or "professional(32%)". Respondents had worked in the building for an average of 5.8 years. Forty-four percent reported having SBS defined as "having one or more symptoms that had occurred at work one or more days a week and tended to get better when away from work". Sex(p=0.001), duration of computer use(p=0.02), use of laser printer(p=0.02), use of cleanser or other office chemicals(p=0.004), feeling too little air movement(0.001), feeling air too dry(p=0.001), and unsatisfied with the current job(p=0.02) were related to an increased prevalence of SBS. Use of cleanser or other office chemicals(p=0.01), feeling too little air movement(p=0.01), and feeling air too dry(p=0.02) remained significant predictors of SBS when adjusting other variables by logistic regression analysis. The results of medical record review revealed a discrepancy in the number of diagnosed asthma cases by personal physician an dan independent physician. Although this study contains several limitations (e.g. cross-sectional study, small numbers of study subjects, etc.), these results indicated that SBS is related to personal, environmental, and psychosocial factors and the precision of diagnosis is critical when evaluating environment-relatedness during disease cluster investigation.

범용 로보트 시뮬레이션 팩키지 개발에 관한 연구 ( Development of a General Purpose Software Package for Robot Simulation )

강대희,주광혁,배한경,김학표 대한전자공학회 1986 대한전자공학회 학술대회 Vol.1986 No.01

3-way 초고압 밸브의 유로제어를 위한 니플 파단 특성에 관한 연구

강대희,란지,정윤재,김원태 한국기계기술학회 2018 한국기계기술학회지 Vol.20 No.6

The 3-way valve have been used as a valve for opening and closing the valve by the flow control in the pressure system of the cryogenic and high pressure environment. In this paper, numerical analysis and experimental study on fracture nipple of 3-way ultra high pressure valve applied to space launch vehicle was carried out. We have developed a 3-way valve numerical simulation modeler of cryogenic environment usingcommercial software ANSYS 18.2. As results of numerical analysis, optimum nipple condition was derived. In addition, a 3-way valve prototype was fabricated and the fracture test was performed and compared with the numerical analysis results.

Determinants of Poor Self-rated Health in Korean Adults With Diabetes

강대희,이휘원,Minkyo Song,Jae Jeong Yang 대한예방의학회 2015 Journal of Preventive Medicine and Public Health Vol.48 No.6

Objectives: Self-rated health is a measure of perceived health widely used in epidemiological studies. Our study investigated the determinants of poor self-rated health in middle-aged Korean adults with diabetes. Methods: A cross-sectional study was conducted based on the Health Examinees Study. A total of 9759 adults aged 40 to 69 years who reported having physician-diagnosed diabetes were analyzed with regard to a range of health determinants, including sociodemographic, lifestyle, psychosocial, and physical variables, in association with self-rated health status using multivariate logistic regression models. A p-value <0.05 was considered to indicate statistical significance. Results: We found that negative psychosocial conditions, including frequent stress events and severe distress according to the psychosocial well-being index, were most strongly associated with poor self-rated health (odds ratio [OR]Frequent stress events, 5.40; 95% confidence interval [CI], 4.63 to 6.29; ORSevere distress, 11.08; 95% CI, 8.77 to 14.00). Moreover, younger age and being underweight or obese were shown to be associated with poor self-rated health. Physical factors relating to participants’ medical history of diabetes, such as a younger age at diagnosis, a longer duration of diabetes, insulin therapy, hemoglobin A1c levels of 6.5% or more, and comorbidities, were other correlates of poor reported health. Conclusions: Our findings suggest that, in addition to medical variables, unfavorable socioeconomic factors, and adverse lifestyle behaviors, younger age, being underweight or obese, and psychosocial stress could be distinc factors in predicting negative perceived health status in Korean adults with diabetes.

우편 설문 응답 양상에 관한 경험

강대희,안윤옥,Kang, Dae-Hee,Ahn, Yoon-Ok 대한예방의학회 1988 Journal of Preventive Medicine and Public Health Vol.21 No.2

1. 회신율은 연구 주관기관이나 설문조사 내용, 표본의 성격, 응답자에게 주는 이익의 정도, 독촉 방법에 따라 많은 차이를 보이겠지만 본 사례에서 우편설문에 관한 응답양상을 살펴본 바, 회신율에 있어서는 1차 발송후 총 대상에 대하여 약 15-20% , 미응답 대상에 대한 2차 발송 후 2차 대상의 약 30%, 1, 2차 미응답 대상에 대한 3차 발송후 3차 대상의 약 20%정도의 회신율을 보여 총 회신율에 있어서는 약 54%정도를 보이었다. 이것은 사회과학 연구 조사에서의 회신율 10-25%에 비하여는 상당히 높다고 할 수 있고(김경동, 1986), 질문서 회신율이 50%면 분석의 목적 상 무난하다고 보아야 하고, 60%면 좋은 편이고, 70%가 넘으면 아주 훌륭하다는 Babbie(1973)의 의견에 비추어 볼 때 무응답 대상에 대한 비교연구가 수반되어야 정확한 판단을 내릴 수 있겠지만 본 사례에서의 회신율은 그런대로 만족할 수 있는 수준이라고 생각된다. 2. 미응답 대상에 대한 독촉 발송 시기에 있어서는 미응답 대상에 대하여 최초 발송 2주일 후 정도가 적절할 것으로 판단되며, 3차 발송까지 시행하는 것이 회신율을 높일 수 있는 방법으로 생각된다. 3차 발송 이후에도 응답이 없는 경우 또다시 독촉(4차 이상 발송)하여도 전체 회신율에는 크게 영향을 미치지 않을 것으로 예상된다. Christopher는 정부의 후원을 받는 조사 연구의 경우 회신율이 높다고 보고하였는데 이번 조사연구에서도 관련 부처로부터의 협조 공문이 회신율을 높이는데 기여하였다고 사료된다(Oppenheim, 1966).

포장기계 경쟁력 제고를 위한 제언

강대희 (사)한국포장협회 2001 包裝界 Vol.94 No.-

직업성 질환에서 유전적인 영향

강대희 가톨릭대학교 산업의학센터 2000 韓國의 産業醫學 Vol.39 No.4

The differences in disease occurrence varies from country to country. These might be either due to difference in genetic constituency in individuals from different ethnic backgrounds or to environmental factors including diet and personal habits, or more plausibly to the interactive effects of genetic and environmental factors. Post-gencomic era opens the potential application of functional genomics to the fields of occupational health. This mini-review of $quot;genetic effects in occupational diseases$quot; deals with several newly challenging areas of application of genetic information in occupational health Recent reports regarding the genetic susceptibility to occupational asthma, particularly DRB1 or DQB1 HLA class polymorphism give us interesting insights that the genetic information may play an important role in development of occupational asthma and this can be a good example of how genetic information provide us to better understanding for etiology of occupational diseases. Genetic testing for the employees who apply new jobs or genetic monitoring for the employees in certain hazardous environments also stimulate important issues of ethical, social, and economical problems among employees enforced to take the genetic testing. Finally, how genetic information can be used in delineating work-relatedness in compensating cases for occupational diseases was reviewed.

이동 로보트의 행동과 센서융합

강대희,원도문웅 대한전자공학회 1994 전자공학회지 Vol.21 No.4

채 정민 씨의 글을 읽고

강대희 한글학회 1938 한글 Vol.6 No.2