• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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• pp.127-132
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• 2002

Recent deepwater offshore structures in Gulf of Mexico utilize butt welded tubular joints. Application of welded tubular joint includes tendons, production risers, and steel catenary risers. Fatigue life assessment of these joints becomes more critical because the structures to which they are attached are allowed to undergo cyclic and sometimes large displacements around an anchored position. Estimating the fatigue behavior of these tubular members in the design stage is generally conducted by using S-N curves specified in the codes and standards. Applying the stress concentration factor of the welded structure to S-N approach often results in very conservative assessment because the stress field acting on the tubular has a non-uniform distribution through the thickness. Fracture mechanics and fitness for service (FFS) technology have been applied in the design of the catenary risers. This technology enables the engineer to establish proper requirements on weld quality and inspection acceptance criteria to assure satisfactory structural integrity during its design life. It also provides guidance on proper design curves to be used and a methodology for accounting for the effects of non-uniform stress distribution through the wall thickness. An attempt was made to develop set of S-N curves based on fracture mechanics approach by considering non-uniform stress distribution and a threshold stress intensity factor. Series of S-N curves generated from this approach were compared to the existing S-N curves. For flat plate butt joint, the S-N curve generated from fracture mechanics matches with the IIW class 100 curve when initial crack depth was 0.5 mm (0.02"). Similar comparison with API X′ was made for tubular joint.. These initial crack depths are larger than the limits of inspection by current Non-destructive examination (NDE) means, such as Automatic Ultrasonic Inspection (AUT). Thus a safe approach can be taken by specifying acceptance criteria that are close to limits of sizing capability of the selected NDE method. The comparison illustrates conservatism built into the S-N design curve.

• 한국보건간호학회지
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• 제37권1호
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• pp.80-96
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• 2023

Purpose: This study examined the trends in domestic research that applied theory to diabetes patients to suggest future directions of nursing practice and research for diabetes patients. Methods: This scoping review followed the Joanna Briggs Institute guidance. The population was diabetes patients; the concept was a research that applied theory and had no limitations in context. Eligible studies were retrieved from electronic databases of RISS, KMbase, KoreaMed, NDSL, NAL, and nine major domestic nursing journals. Of the 509 retrieved articles, 20 studies met the inclusion criteria. Results: The study included the community (57.1%), and the subjects were mainly type 2 diabetes patients (42.9%). The Information-Motivation-Behavior skills (IMB) model was the most applied theory (36.4%). The theories were primarily from psychology disciplines (72.7%) and predominantly applied as a conceptual framework of the study (55%). Conclusion: The studies that applied theory were conducted mainly in the community. The IMB model was the most applied theory, and the theory was most applied as the conceptual framework. Efforts to close the theory-practice gap and further studies on developing nursing interventions based on theory and verifying their effectiveness are needed to improve nursing practice and study for diabetic patients.

• 산업융합연구
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• 제21권3호
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• pp.49-56
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• 2023

본 연구는 성장마인드셋과 진로관여행동의 관계에서 진로적응성의 매개효과를 검증하는데 그 목적이 있다. 서울,경기,충청도 소재 대학생을 대상으로 온라인 설문을 하여 최종 203개의 자료가 수집되었다. 자료분석은 SPSS 25.0, AMOS 25.0 소프트웨어를 활용하여 빈도분석, 기술통계 분석을 수행했고 구조방정식모형 분석은 확인적 요인분석을 기반으로 측정 모형을 평가한 이후 구조적 관계를 확인했다. 연구결과 성장마인드셋은 진로관여행동에 직접영향을 미쳤으며(𝛽=.254, p<.01) 성장마인드셋이 진로적응성을 거쳐 진로관여행동에 미치는 매개효과 또한 통계적으로 유의한 것으로 나타났다(𝛽 =.137, p<.01). 본 연구에서는 대학생의 올바른 진로 안내를 위해 진로관여행동의 촉진이 중요하며 이를 위해 성장마인드셋과 진로적응성의 함양을 위한 실질적인 전략이 필요하다는 것을 시사하고 있다.

• 한국식생활문화학회지
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• 제24권3호
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• pp.256-266
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• 2009

The purpose of this study was to determine conditions of dining behaviors, sleep patterns, rates of obesity and intake of snacks and self-purchased snacks deriving from the lack of sleep in academic high school students. The anthropometric characteristics, height and weight (p<0.05), and the distribution of obesity index (p<0.001) showed significant differences between males and females. Dining scores for both male and female students decreased as the frequency of day time napping increased. Although, there was no significant difference in obesity-related "lack of sleep" between males and females, the rate of "being overweight" was slightly higher in female students who indicated that they experienced a "lack of sleep" than female students that indicated "no lack of sleep". While, whether intake of snacks and self-purchased snacks or not, day time napping frequency affected not to male students. However, the frequency of day time napping among females who ate snacks one or more times a day was higher (p<0.05), and a greater frequency of eating self-purchased snacks correlated with a greater frequency of day napping (p<0.01). Consequently, lack of sleep was identified as one of the factors increasing the frequency of intake of snacks and self-purchased snacks in females. Thus, this study suggests that dining behavior guidance should be given along with systematic and continual nutrition education so that the intake of snacks and self-purchased snacks can be moderated to optimize the physical and mental growth and development of adolescents.

• Journal of Dental Anesthesia and Pain Medicine
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• 제23권5호
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• pp.265-271
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• 2023

Background: Anxiety and fear in children's dental care are major impediments to successful dental care. High-quality dental treatment can be achieved using various behavioral control methods; however, conscious sedation using drugs can be used if behavioral control is difficult, owing to excessive fear and anxiety. This study aimed to examine the trends in conscious sedation implemented in pediatric dentistry at the Dankook University Dental Hospital over the past 11 years. Methods: This study included 6,438 cases of dental treatment under conscious sedation conducted over 11 years between January 2011 and December 2021 in the Department of Pediatric Dentistry at Dankook University Dental Hospital. Results: Over the past 11 years, the number of dental treatments under sedation has increased. In the case of inhalation sedation using nitrous oxide, the rate of increase was approximately twice every year, and the use of midazolam gradually decreased. The average age of children who underwent sedation was 5.11 years, and the rate of sedation treatment in children aged <4 years tended to decrease, while that of children aged >5 years tended to increase. This is related to the trend of changes in drugs used. In a sex-based survey, sedation treatment rate was higher in males than that in females. Conclusion: Appropriate selection of sedatives can reduce the frequency of general anesthesia and minimize complications through efficient and safe dental treatments. Trend analysis of sedation by year will help provide guidelines for the appropriate selection of sedation for dental treatment of children and patients with disability.

• Journal of Dental Anesthesia and Pain Medicine
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• 제24권3호
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• pp.195-204
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• 2024

Background: Distraction is a technique used to divert a patient's attention from unpleasant procedures. This study aimed to evaluate the effectiveness of kaleidoscopy, virtual reality, and video games in reducing anxiety and pain during invasive dental procedures in children. Methods: Sixty-six children aged 6 to 9 years were randomly assigned to three groups during local anesthesia administration: Group 1 (kaleidoscope), Group 2 (virtual reality), and Group 3 (mobile video games). The anxiety of the children was evaluated using physiological measures (heart rate) at three different time points: before, during, and after the procedure. The Raghavendra, Madhuri, and Sujata pictorial scale was used as a subjective measure before and after the procedure. Subjective measures of pain were assessed using the Wong-Baker Faces Pain Scale. The data were statistically analyzed using the Kruskal-Wallis and Wilcoxon signed-rank tests. Results: In the intergroup comparison, there were no statistically significant differences in the physiological measures of anxiety scores between the three groups before, during, and after distraction. Raghavendra, Madhuri, and Sujata pictorial scale scores were assessed before and after distraction, but no statistically significant differences were observed. Among the three groups, the children in Group 2 showed a significant reduction in pain scores. Conclusion: Compared with kaleidoscopes and video games, virtual reality is a promising distraction technique for reducing dental fear, anxiety, and pain during local anesthesia administration in children.

• Journal of Dental Anesthesia and Pain Medicine
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• 제24권1호
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• pp.57-65
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• 2024

Background: The objective of behavioral guidance is to establish effective communication that aligns with a child's requirements to manage disruptive behavior. This study aimed to evaluate the effectiveness of the Tell-Show-Do and Ask-Tell-Ask techniques in managing dental anxiety in children during their initial appointment. Methods: The study included 50 children (28 boys and 22 girls) without any prior experience between the ages of 7 and 11 at their first dental visit. The children were randomly categorized into two groups: Group 1, Tell Shows Do, and Group 2, Ask-Tell-Ask. Subsequently, all children underwent noninvasive treatment procedures such as restorations, sealants, and oral prophylaxis. Furthermore, behavioral management techniques were employed based on the allocated group. Finally, anxiety levels for all children were assessed using the Raghavendra, Madhuri, and Sujata Pictorial Scale (RMS-PS) and heart rate at three different intervals (before, during, and after). The obtained data were entered into Microsoft Excel, and statistical analysis was performed using SPSS software. A paired t-test and Mann-Whitney U-test were used to compare the mean and median values of the two groups and determine their effectiveness. Results: Children in the TSD group exhibited statistically significant heart rates and RMS-PS scores in intra-group comparisons. However, children in the ask-tell-ask group showed a significant reduction only in the RMS-PS scores (P < 0.001) but not in the measures used to assess heart rate (P < 0.001). Conclusion: Tell-Show-Do was more effective than ask-tell-ask in alleviating dental anxiety in children. The simultaneous application of these two strategies can synergistically alleviate dental anxiety during a child's initial dentist appointment.

• Nuclear Engineering and Technology
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• 제55권12호
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• pp.4367-4381
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• 2023

Nuclear power plants are increasingly being equipped with digital I&C systems. Although some probabilistic safety assessment (PSA) models for the digital I&C of nuclear power plants have been constructed, there is currently no specific internationally agreed guidance for their modeling. This paper presents an initiative by the OECD Nuclear Energy Agency called "Digital I&C PSA - Comparative application of DIGital I&C Modelling Approaches for PSA (DIGMAP)", which aimed to advance the field towards practical and defendable modeling principles. The task, carried out in 2017-2021, used a simplified description of a plant focusing on the digital I&C systems important to safety, for which the participating organizations independently developed their own PSA models. Through comparison of the PSA models, sensitivity analyses as well as observations throughout the whole activity, both qualitative and quantitative lessons were learned. These include insights on failure behavior of digital I&C systems, experience from models with different levels of abstraction, benefits from benchmarking as well as major contributors to the core damage frequency and those with minor effect. The study also highlighted the challenges with modeling of large common cause component groups and the difficulties associated with estimation of key software and common cause failure parameters.

• 한국초등과학교육학회지:초등과학교육
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• 제37권2호
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• pp.206-218
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• 2018

The purpose of this study is to analyze the teaching behaviors and visual attention according to teacher's career in Elementary Science Inquire-based Class. Participants were four elementary school teachers in Seoul. They were all in grade 5 and taught science. According to the experience of elementary science education, two novice teachers and two expert teachers were identified. Participants taught Respiration in the 'Structure and Function of our Body' in the elementary science fifth grade. The mobile eye tracker used in this study is SMI's ETG 2w, which is a binocular tracking system. In addition, a video camera was installed behind the classroom to record the entire class. We recorded all the contents of the recorded video and analyzed the results. In this study, the actual practice time, participant's visual attention, and decentralized attention ability were analyzed by class phase. The results of the study are as follows. First, there was a difference between planned class time and actual practice time. The novice teachers were having difficulty in reconstructing the contents of education, and the expert teachers were reconstructing the curriculum and interacting with the students with high understanding and application of the curriculum. There were many differences between the novice teachers and the expert teachers in the tour guidance to confirm student activities. Second, if we look at the visual attention on the area related to teaching and learning by class phase, the novice teacher concentrates all the steps in a specific area, expert teachers showed an equal visual attention to meaningful areas of teaching and learning activities. Third, there was a statistically significant difference in activities 1-1, 1-2, 2-1, and 2-2 when the participants' decentralized attention ability. Expert teachers frequently checked students' understanding and interests. There was a lot of interaction with students. It is also shown through the decentralized attention ability that the novice teachers concentrate on a specific area, and the expert teachers have a high degree of decentralized attention ability and visual attention evenly.

• 해양환경안전학회지
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• 제15권4호
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• pp.369-374
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• 2009

해기직업에 대한 안정이 없으면 인적요인에 의한 해양안전도 크게 개선되지 않을 것으로 판단된다. 따라서 해기직업 진입단계에서 부터 은퇴하기까지 생애에 걸쳐 해기사의 직업경로를 개발함으로써 보다 장기적이고 안정적인 해기직업 생활과 해양안전을 확보할 수 있을 것이다. 이를 위해 해기직업 경로모델을 설정하고 해기교육기관 진입자, 해상근무자, 육상근무자 2,830명을 대상으로 설문조사를 실시하여 가설을 검증하였다. 직업경로에 따른 행동요인 분석 결과, 첫째, 해기교육기관 진입자들에게 교육환경 개선과 해기직업생활에 대한 충분한 정보를 전달하고 둘째, 소득수준과 같은 경제적 요인은 해기직업 진입자에게는 동기요인이 되지 못하며 셋째, 적정 시기에 육상근무를 위한 하선유도가 해기직업의 매력화와 파생적인 장기승선 효과를 기대할 수 있으며 넷째, 해기면허체계를 단순화시켜 조기에 상위면허를 취득함으로써 상위직책에 근무할 수 있는 기회를 제공할 필요가 있다.