• Computers and Concrete
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• 제32권6호
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• pp.615-623
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• 2023

Crack detection is an essential method to ensure the safety of dam concrete structures. Low-quality crack images of dam concrete structures limit the application of neural network methods in crack detection. This research proposes a modified attentional mechanism model to reduce the disturbance caused by uneven light, shadow, and water spots in crack images. Also, the focal loss function solves the small ratio of crack information. The dataset collects from the network, laboratory and actual inspection dataset of dam concrete structures. This research proposes a novel method for crack detection of dam concrete structures based on the U-Net neural network, namely AF-UNet. A mutual comparison of OTSU, Canny, region growing, DeepLab V3+, SegFormer, U-Net, and AF-UNet (proposed) verified the detection accuracy. A binocular camera detects cracks in the experimental scene. The smallest measurement width of the system is 0.27 mm. The potential goal is to achieve real-time detection and localization of cracks in dam concrete structures.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.291-297
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• 2003

Fluid film tilting pad journal bearings are widely used for large steam turbines. However, bearing problems by pad fluttering, such as fatigue damage in the upper unloaded pad, the break of locking pins and the wear of pinholes etc., are frequently taken place in the actual steam turbines. The purpose of the present work is to investigate on the mechanism of pad fluttering and the prevention of pad fluttering with the variation of preload(m) in a tilting pad journal bearing. It is estimated that upper pad is easy to flutter because the film shape of upper pad is diverged one from the analysis of moment direction acting on pivot point. Effective preload range in order to be statically loaded pad under all operating conditions is suggested as m＞0.5. Also, as a bearing that can be prevented pad fluttering, design modified bearing is suggested. For the adjustment in actual steam turbines, bearing and rotor dynamic analysis are performed to identify bearing characteristics and to verify the reliability of rotor-bearing system.

• 대한치과의료관리학회지
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• 제7권1호
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• pp.10-20
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• 2019

Korean dental hygienists perform more tasks in dental clinics than are described in the law. The purpose of this study was to investigate the actual work of Korean dental hygienists in dental clinics using an observational study design. Two dental hygienists observed and recorded the work performed in 1 day from the time of commencement to the time of leaving work by 18 dental hygienists working in the dental clinic in a single area. Data management, prevention of infection, counseling, calculus removal, radiography, assistance of fixed orthodontic treatment, assistance of fixed prosthetic treatment, and preparation for implant surgery were recorded. Among the tasks that take more than 1 min, the most time-consuming tasks were document management, infection control, consultation, calculus removal, preparation for implant surgery, assistance of orthodontic treatment, and assistance of fixed prosthetic treatment. Korean dental hygienists are performing various tasks, such as infection control, dental hospital/clinic management, oral disease prevention, and dental treatment assistants.

• 대한안전경영과학회지
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• 제25권4호
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• pp.105-115
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• 2023

The purpose of this study is to identify psychological anxiety factors related to firefighters' field activities and suggest improvement measures. To investigate the actual status of psychological anxiety factors, a survey was conducted on approximately 3,500 current firefighters, and the responses of 505 people who participated in the survey were analyzed. As a research method, frequency analysis and cross-analysis were conducted according to the general characteristics of the participants to determine the actual level of psychological anxiety in each work field and the results were analyzed. As a result of the analysis, it was statistically confirmed that firefighters feel a lot of psychological burden due to legal and institutional inadequacies during dispatch, return, or field activities, and frequent friction with civil servants is also a major cause of psychological anxiety. Therefore, based on the results of this study, it is proposed to establish a permanent legal support team in each city and province, designate and operate a hospital dedicated to psychological treatment, and establish a special provision for traffic accidents during the return of fire trucks so that firefighters can concentrate on their duties without psychological anxiety. do.

• 한국산학기술학회논문지
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• 제18권2호
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• pp.342-348
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• 2017

본 연구는 유아의 문제행동에 대한 부모와 교사의 인식차이 연구로 유아의 문제행동에 대해 부모와 교사 간 인식차이 분석 결과 유아의 모든 문제행동 유형에 대하여 부모와 교사 간의 인식 차이가 뚜렷한 것으로 나타나고 특히 부모보다 교사들이 문제행동에 대해서 비교적 문제가 있다고 인식하고 있는 것으로 나타났다. 그리고 유아 지도전략에 대한 부모와 교사의 인식 차이에 있어서도 유아의 지도전략에 대해 부모와 교사의 인식에 있어, 반응적 상호작용과 교육기관에서의 예방실제가 선호되는 것으로 나타나 이는 부모보다 교사가 통계적으로 유의미하게 높은 것으로 나타난 반면 사회정서 전략에 있어서는 유의미한 차이가 없는 것으로 나타났다. 이 같은 결과는 원래 유아들의 다양한 문제행동을 통제관리 해야 하는 교사의 입장에서 편중된 지도전략보다 사회 정서적으로 인식되고 있는 공통적 지도전략에 바탕을 두되 교사 유아 간 발생되는 문제행동 유형과 대상유아에 따라 반응적 상호작용하는 지도전략이 선호되고 특히 돌출문제 행동이 많이 발생하는 유아의 행동 특성을 고려할 때 돌출문제 유아의 행동억제와 예방에 중점을 둔 반응적 상호작용 전략과 예방실제 지도전략이 선호되고 있음을 시사한 것으로 평가 할 수 있다.

• 한국방재학회 논문집
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• 제10권3호
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• pp.53-59
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• 2010

전 세계는 자연환경의 변화로 지역적 폭우의 발생, 가뭄현상의 장기화, 대규모 지진발생이 증가하고 있는 실정이다. 우리나라의 경우도 방재개념이 적용되지 않은 지역에서 반복적으로 재해가 발생하여 대책이 시급하다는 지적을 받고 있다. 이에 소방방재청에서는 2009년부터 재해취약지역을 대상으로 방재시범마을의 조성을 추진하며 방재대책의 개선방안을 모색하고 있다. 본 연구에서는 방재마을구축과 관련하여 방재마을의 개념 및 사업 유형에 대해 정리하고, 관련제도, 국내 외 시범사업의 사례분석을 통해 방재마을 구축에 관한 발전전략을 제시하고 방재마을 조성에 대한 기본개념을 제시하여 방재마을 구축의 기초자료를 제시했다.

• 한국인구학
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• 제7권1호
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• pp.39-77
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• 1984

It has been well known that the family pjanning programme has a great deal with declining fertility in Korea. The present study was aimed to measure the impact of family planning program me on fertility level. The specific objectives are to overview the demographic changes ncluding fertility declining and to calculate actual number of birth averted during the last 20 years. The data used for the present study was collected from various sources such as service statistics of the government, survey and research reports, and other related papers. The tool used for calculation of birth prevention was "Standard Couple Years of Protection (SCYP) Method" developed by M Gorosh. The major findings are summarized as follows ; Total of family planning acceptors from 1962 to 1982 was 9,556,153. On the basis of this data, total of averted births was calculated for eachcontraceptive Method ; 1.Oral pills, total number of acceptors from 1968 to 1982 was 2.347,259. Estimated number of birth averted was 272 ,303 .70 and the Coefficient of births prevention per acceptor turned out to be 0.114 2.Condoms, total number of birth acceptors from 1962 to 1982 was 2,874,216. Estimated number of birth averted was 220,495.30 and the coefficient of births prevention per acceptor turned out to be 0.077. 3.IUD, total number of acceptors from 1962 to 1982 was 5,101 .650. Estimated number of birth averted was 1,377,584.76 and the coefficient of births prevention per acceptor turned out to be 0.270. 4.Vasectomy, total number of acceptors from 1962 to 1982 was 556,508. Estimated number of birth averted was 626 ,128 .80 and the coefficient of births prevention per acceptor turned out to be 1.125. 5.Tubaligation total number of birth acceptors from 1972 to 1982 was 1 210,775. Estimated number of birth averted was 1 ,117 679.00 and thecoefficient of birtlts prevention per acceptor turned nut to be 0.923. 6.Abortion, total number of acceptors from 1973 to 1982 was 465,525. Estimated number of birth averted was 355 ,283 .60 and the coefficient of births prevention per acceptor turned out to be 0.763.

• 한국컴퓨터정보학회논문지
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• 제24권2호
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• pp.179-184
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• 2019

As the tendency of children's overdependence on smart phones increased, it was obligatory to carry out preventive education more than once a year in kindergarten and day care center, but there is no specific guidance on contents and method of preventive education. This is due to the lack of prior studies on the actual use of smartphones and the influence variables of infants and young children. The purpose of this study was to investigate the effects of use time, frequency of use, and sociological background variables on the actual situation of smartphone usage and overdependency on smartphone among 3-5 year old children nationwide. For the analysis, the frequency of the use of smartphone for 3-5 year old children was analyzed by frequency analysis, and the influence variables were correlated and multiple regression analysis. Research shows that smartphone overdependence of 3-5 year old children have an influence on the use time and frequency of use. The results should include content that restricts the use time and frequency of use of smartphones and prevention education programs for 3-5 year olds and young children. Suggesting a need for a transition to the educational method used.

• 한국학교보건학회지
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• 제26권3호
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• pp.158-168
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• 2013

Purpose: Elementary schools are regarded as the best community setting for implementing obesity prevention programs and health teachers (HTs) are the main health professionals who can provide obesity prevention services. However, there is insufficient information on the actual conditions of school-based obesity prevention/ management programs in Korean elementary schools. The purpose of the study was to investigate the actual conditions of school-based obesity prevention/management programs, perceived and experienced by elementary school HTs, which may provide basic data for developing effective and sustainable programs for early childhood. We investigated (1) HTs' ratings on the program's importance, the confidence in the program's implementation, and the factors associated with the program's success (2), the correlates of the importance and confidence levels (3), the program's effectiveness and the factors associated with its sustainability, which were evaluated by HTs, and (4) the correlates of the effectiveness levels. Methods: The participants, 147 HTs working for elementary schools in Seoul were asked to fill out self-administrated questionnaires through mail. Results: The participants' rate on the program's importance was 7.1 on average (0~10 scale) and that on the confidence in the program's implementation was 6.2 (0~10 scale). Moreover, > 25% of the participants reported student and parent participation as a factor associated with the program's success. Of the total participants, 45.6% reported they had actually experienced the program, giving 4.8 points (0~10 scale), on average, in the evaluation of the program's effectiveness and > 22.0% of the participants regarded student and parent participation as a factor associated with the program's sustainability. The HTs' confidence in the program's implementation was a strong correlate of the effectiveness evaluated by HTs. Conclusion: School-based obesity prevention/management programs tend to be highly prioritized by HTs in elementary schools. To implement an effective obesity program in elementary schools, educational support for HTs is needed in order to enhance their confidence levels on the program's implementation.

• 치위생과학회지
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• 제15권6호
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• pp.845-850
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• 2015

이번 연구는 진료실 내 안전사고에 의한 외상 경험 실태와 예방 실천에 대해 파악하는 연구이다. 치과 병 의원에서 종사하고 있는 치과위생사 366명을 대상으로 자기기입식 설문조사를 실시하였다. 최근 6개월 동안 외상 경험은 연구대상자 366명 중 307명(83.9%)이 경험한 적이 있다고 응답하였고 유형으로는 전체응답자 366명 중 찔림이 294회(80.3%)로 가장 경험이 많았고 절상, 찰과상, 화상 순이었다. 외상 원인으로는 찔림의 원인이 된 기자재 중 explorer가 93명(25.4%)으로 가장 많았으며 needle이 66명(18.0%)로 그 다음으로 나타났다. 절상(베임)은 blade가 36명(9.8%), 화상 원인은 sterilizer로 26명(7.1%), 찰과상 원인은 movable cart 47명(12.8%)으로 가장 많았다. 찔림 경험을 한 후 응급처치로 알코올 솜으로 닦는 경우가 40.8%으로 가장 많았고, 응급실 방문은 없는 것으로 나타났다. 절상(베임)을 경험 한 후 응급처치로 베타딘으로 소독하는 경우가 42.8%으로 가장 많았고, 화상을 경험 후 응급처치는 찬물로 씻는 경우가 73.0%으로 절반이 넘게 나타났다. 일반적 특성에 따른 외상 경험의 차이를 조사한 결과 연령, 근무경력(p<0.001), 최종학력(p=0.006), 직위, 업무영역(p=0.001)에서 통계적으로 유의한 차이가 있다고 나타났다. 일반적 특성에 따른 안전사고 예방 실천도의 차이를 조사한 결과 외상 경험 여부(p=0.030), 연령(p=0.015)과 치과유형(p=0.003)이 통계적으로 유의한 차이가 있는 것으로 나타났다. 치과 외상 경험 실태와 안전사고 예방 실천에 관련된 연구를 통하여 진료실 내 안전사고 예방이 체계적인 과정으로 확립되어야 하고 정기적인 교육을 통하여 안전에 대한 중요성을 부여하여야 한다.