• Safety and Health at Work
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• 제11권2호
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• pp.178-186
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• 2020

Background: Cognitive impairment is a public health burden. Our objective was to investigate associations between work hours and cognitive function. Methods: Multi-Ethnic Study of Atherosclerosis (MESA) participants (n = 2,497; 50.7% men; age range 44-84 years) reported hours per week worked in all jobs in Exams 1 (2000-2002), 2 (2002-2004), 3 (2004-2005), and 5 (2010-2011). Cognitive function was assessed (Exam 5) using the Cognitive Abilities Screening Instrument (version 2), a measure of global cognitive functioning; the Digit Symbol Coding, a measure of processing speed; and the Digit Span test, a measure of attention and working memory. We used a prospective approach and linear regression to assess associations for every 10 hours of work. Results: Among all participants, associations of hours worked with cognitive function of any type were not statistically significant. In occupation-stratified analyses (interaction p = 0.051), longer work hours were associated with poorer global cognitive function among Sales/Office and blue-collar workers, after adjustment for age, sex, physical activity, body mass index, race/ethnicity, educational level, annual income, history of heart attack, diabetes, apolipoprotein E-epsilon 4 allele (ApoE4) status, birth-place, number of years in the United States, language spoken at MESA Exam 1, and work hours at Exam 5 (β = -0.55, 95% CI = -0.99, -0.09) and (β = -0.80, -1.51, -0.09), respectively. In occupation-stratified analyses (interaction p = 0.040), we also observed an inverse association with processing speed among blue-collar workers (adjusted β = -0.80, -1.52, -0.07). Sex, race/ethnicity, and ApoE4 did not significantly modify associations between work hours and cognitive function. Conclusion: Weak inverse associations were observed between work hours and cognitive function among Sales/Office and blue-collar workers.

• 한국기록관리학회지
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• 제17권1호
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• pp.31-49
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• 2017

본 연구에서는 서울시 25개 기초자치단체 기록관을 대상으로 서비스 품질에 대한 기대수준과 인식수준을 측정하고자 하였다. 이를 위해 문헌연구와 현황조사를 통해 5개 요인과 31개 문항으로 구성된 평가 지표를 도출하였고, 주 이용자인 소속 기관 공무원을 대상으로 설문조사를 실시하였다. 분석 결과, 기초자치단체 기록관의 서비스 품질은 전반적으로 기대수준이 인식수준보다 높아 실제 서비스가 이용자를 만족시키지 못하고 있다는 것을 확인할 수 있었으며, 그 차이도 통계적으로 유의한 것으로 나타났다. 본 연구는 과정적 품질에 기초하여 국내에서는 처음으로 기초자치단체 기록관의 서비스 품질에 대한 현황을 분석하고 개선방안을 제안하였다는 점에서 의의가 있다.

• 한국정보통신학회논문지
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• 제21권5호
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• pp.967-973
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• 2017

클러스터링은 균일한 특성을 가지는 데이터를 클러스터로 묶기 위해 사용되는 비교사 학습 방법 중 하나로 다양한 응용에 사용되고 있으며 FCM(Fuzzy C-Means)이 대표적인 방법 중 하나이다. 하지만 FCM에서 주로 사용되는 유클리드 거리 척도는 밀도가 높은 클러스터가 클러스터링 결과에 많은 영향을 미쳐 밀도가 높은 쪽으로 클러스터의 중심을 위치시키는 문제가 있으며, 이를 해결하기 위한 방법 중 하나가 클러스터 중심 사이의 거리가 가능한 멀어지도록 하는 밀도 무관 클러스터링이다. 하지만 밀도 무관 클러스터링 역시 클러스터 중심 사이의 거리를 정확히 제어하기가 어렵다. 이 논문에서는 클러스터 중심 사이의 거리가 멀어지도록 할뿐만이 아니라 클러스터 중심이 밀도가 높은 곳에 위치하도록 하는 항을 추가한 개선된 밀도 무관 클러스터링 방법을 제안한다. 제안하는 방법은 FCM이나 밀도 무관 클러스터링에 비해 실제 클러스터 중심으로 수렴하는 경우가 더 많다는 것을 실험 결과를 통해 확인할 수 있다.

• Parasites, Hosts and Diseases
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• 제47권2호
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• pp.159-165
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• 2009

House-residual spraying and insecticide-treated bed nets have achieved some success in controlling anthropophilic and endophagic vectors. However, these methods have relatively low efficacy in Korea because Anopheles sinensis, the primary malaria vector, is highly zoophilic and exophilic. So, we focused our vector control efforts within livestock enclosures using ultraviolet black light traps as a mechanical control measure. We found that black light traps captured significantly more mosquitoes at 2 and 2.5 m above the ground (P<0.05). We also evaluated the effectiveness of trap spacing within the livestock enclosure. In general, traps spaced between 4 and 7m apart captured mosquitoes more efficiently than those spaced closer together (P>0.05). Based on these findings, we concluded that each black light trap in the livestock enclosures killed 7,586 female mosquitoes per trap per night during the peak mosquito season (July-August). In May-August 2003, additional concurrent field trials were conducted in Ganghwa county. We got 74.9% reduction (P<0.05) of An. sinensis in human dwellings and 61.5% reduction (P>0.05) in the livestock enclosures. The black light trap operation in the livestock enclosures proved to be an effective control method and should be incorporated into existing control strategies in developed countries.

• KDI Journal of Economic Policy
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• 제29권3호
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• pp.29-73
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• 2007

보육보조금은 일반적으로 여성의 노동시장참여를 용이하게 해주려는 것과 아동이 양질의 보육 및 교육 환경에서 돌보아지는 것을 돕는 목표로 지급된다. 본 연구는 보육시설을 이용하는 영아가구에 보육료를 지원하는 영아기본보조금의 효과를 살펴봄으로써 영아기본보조금이 그 정책목표를 달성하고 있는지 검토한다. 기본보조금이 2006년 민간보육시설에만 도입되었고 유아는 제외하고 영아에게만 지급된다는 준실험적(Quasi-Experiment) 설정을 이용하여 시설 측면과 가구 측면의 효과를 분석한다. 분석 결과, 보조금으로 인해 영아의 이용비중이 높은 보육시설에서는 교사의 처우 및 시설환경이 개선되는 등의 효과가 나타났으나 여성의 노동공급에는 거의 영향을 미치지 않았고, 수요자의 보육만족도에도 부정적 영향을 미친 것으로 나타났다.

• 센서학회지
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• 제6권3호
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• pp.228-236
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• 1997

방사성 물질은 인체에 매우 위험하여 정확한 제어와 유출 방지 및 정확한 측정의 필요성이 요구된다. 본 논문에서는 GM 계수기를 사용하여 방사성 물질의 양을 정확히 측정할 수 있는 시스템을 설계하였으며, 계수 프로그램과 측정한 데이터를 저장하거나 외부 장치로 전송향 수 있는 운용 프로그램을 개발하였다. 제작한 시스템과 계수 프로그램은 국내외에서 개발하고 있는 GM 계수관형 방사선 측정기로 원자력 발전소 및 연구소에서 띠러 가지 방식으로 활용될 수 있도록 설계되었다.

• Communications for Statistical Applications and Methods
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• 제9권2호
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• pp.521-531
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• 2002

Various diagnostic techniques for identifying influential observations are mostly based on the deletion of a single observation. While such techniques can satisfactorily identify influential observations in many cases, they will not always be successful because of some mask effect. It is necessary, therefore, to develop techniques that examine the potentially influential effects of a subset of observations. The partial regression plots can be used to examine an influential observation for a single parameter in multiple linear regression. However, it is often desirable to detect influential observations for a subset of regression parameters when interest centers on a selected subset of independent variables. Thus, we propose a diagnostic measure which deals with detecting influential observations on a subset of regression parameters. In this paper, we propose a measure M, which can be effectively used for the detection of influential observations on a subset of regression parameters in multiple linear regression. An illustrated example is given to show how we can use the new measure M to identify influential observations on a subset of regression parameters.

• 동서간호학연구지
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• 제20권2호
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• pp.112-120
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• 2014

Purpose: The purpose of this study was to compare the differences in characteristics, lactation problems, knowledge, and adaptation of breastfeeding between users and non-users of a lactation clinic. Methods: The descriptive study design was utilized using self-report questionnaires. 446 breastfeeding mothers participated in this study. Data were collected from lactation clinics, postpartum care centers, mother's culture centers, public health centers, pediatrics and obstetrics & gynaecology outpatient clinics in Seoul, Gyeonggi province, and Chungcheongnam province from August 20 to September 30, 2011. The questionnaires to measure lactation problems, knowledge and adaptation of breastfeeding were used. Data were analyzed using SPSS ver. 18.0 for Windows. Results: There was statistically significant differences in the breast feeding problems(t=5.71, p<.001) and breastfeeding knowledge(t=2.87, p=.004) between users and non-users of a lactation clinic. Conclusion: The results of this study may provide a foundation to develop nursing intervention for mothers in breastfeeding, and an evidence to expand the role of nurses as breastfeeding specialists.

• 한국과학교육학회지
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• 제25권6호
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• pp.658-670
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• 2005

Eyes to the Future (ETF) is a year-long, multi-age mentoring program that supports middle-school girls as they make the transition to high school and make informed choices about the opportunities available to them in high school and beyond, particularly in the field of science and technology. In this study, we explore the tension between fidelity and adaptiveness of an educational innovation by examining how teachers in several different schools used a common set of materials and technology to create "native" implementations of an innovative after-school program, adapted to their local setting. First, we found that the implementation of the program varied across the nine clubs. For example, some clubs put a heavy emphasis on science while others emphasized technology. Then, we identified four different profiles of the variations in implementation based on how close the implementation was to the original program and how much clubs were able to customize the implementation to meet their needs and interests. The results showed that some clubs could be regarded as successful because they were faithful to the original program and others were successful because they could adapt the program for their own context. This implies that the measure for success can be and should be multi dimensional.

• 한국산업보건학회지
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• 제29권4호
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• pp.571-581
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• 2019

Objectives: This study was conducted to measure the knowledge, attitude, and practices on occupational health and the analysis factors influencing them among researchers working at corporate research centers. Methods: A total of 298 researchers working at corporate research centers participated in the study. After eliminating 12 insufficient responses, the responses of 286 participants were used for the final estimate. The questionnaire consisted of questions about general and occupational characteristics as well as knowledge, attitude, and practices on occupational health. Results: Factors influencing occupational health practices were type of business, job position, and attitude toward occupational health. Attitude toward occupational health was found to have the greatest influence. Conclusions: It is necessary to develop educational contents appropriate for each type of industry, implement educational programs for researchers working at corporate research centers, and take actions to prevent health problems among researchers through various health-care activities such as experience-based activities and discussions.