• Journal of Welding and Joining
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• 제24권4호
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• pp.39-49
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• 2006

The austenite grain growth model in low alloyed steel HAZ without precipitates was proposed by analyzing isothermal grain growth behavior. Steels used in this study were designed to investigate the effect of alloying elements. Meanwhile, a systematic procedure was proposed to prevent inappropriate neglect of initial grain size (D0) and misreading both time exponent and activation energy for isothermal grain growth. It was found that the time exponent was almost constant, irrespectively of temperature and alloying elements, and activation energy increased with the addition of alloying elements. From quantification of the effect of alloying elements on the activation energy, an isothermal grain growth model was presented. Finally, combining with the additivity rule, the austenite grain size in the CGHAZ was predicted.

• 성인간호학회지
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• 제12권2호
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• pp.256-266
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• 2000

The purpose of this study was to develop and test the validity of the standardized Korean nomenclature of Nursing Outcomes Classification (NOC), developed by Johnson & Maas at the University of Iowa. The four phases of the study were: (1) translation of the NOC into Korean by the research team, (2) four nursing professors and eight nurses with various clinical backgrounds reviewed each nomenclature taking into consideration definitions and nursing activities. The modified Delphi method was used to determine the most appropriate nomenclature for each term; (3) Twenty four academic and clinical experts in nursing were given a questionnaire to rate each Korean nomenclature using a 5 point Likert scale ranging from very inappropriate to very appropriate; (4) the team determined the most appropriate Korean nomenclature for each class of the NOC. The mean validity score of 190 items was 4.54, but several nursing outcome had a score lower than 4.0. They included 'adherence behavior(3.3)', 'ambulation : walking(3.57)', 'transfer performance (3.57)', 'caregiving endurance potential(3.57)'.

• 한국추진공학회지
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• 제21권4호
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• pp.36-43
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• 2017

격벽착화기의 최적 설계를 위하여 여폭약에 의해 생성되는 충격파의 감쇄 특성과 수폭약의 민감도에 관하여 연구하였다. 충격파의 감쇄 특성은 레이저 광간섭계인 VISAR를 이용하여 측정한 격벽의 자유 표면 속도로부터 유도하였고 수폭약의 민감도는 SSGT (Small Scale Gap Test) 결과로부터 구하였다. 격벽착화기의 기폭시험을 통하여 SSGT로부터 구한 화약의 민감도가 격벽착화기와 같이 소량의 화약을 사용하는 시스템에는 충격파 지속 시간이 상이하여 적합하지 않다는 것을 밝혀내었다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1998년도 지반조사위원회 봄 학술세미나
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• pp.37-46
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• 1998

Several researchers have developed a number of theoretical time factors to determine the coefficient of consolidation by biezocone excess pore water dissipation test in soft clay deposits. However, depending on the assumptions and analytical techniques, the estimated coefficient of consolidation could be in a considerably wide range even for a specific degree of consolidation. These solutions are obtained from an initial excess porewater pressure distribution which can be determined from. either the cavity expansion theory or the strain path method. The 야ssipation of the initial excess porelvater pressure has been usally simulated by means of linear-uncoupled consolidation analysis and then the dissipation curve is normalized by the initial excess porewater pressure for easy use. However. since there is no guidelines or rules on which method gives the best solution for obtaining the coefficient of consolidation from the dissipation curve, the final selection was only based on engineer's extrience and Judgements. Thus, such an arbitrary selection might be inappropriate for a specific site to characterize the consolidation behavior. In this paper, we reviewed various theoretical time factors and, based on this consideration, we mentioned needs for researches in selecting a specific solution that is compatible for Korean clays. Also we listed some source of errors that can be encountered in the procedure of dissipation analysis.

• 한국해양공학회지
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• 제26권5호
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• pp.87-93
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• 2012

Many longitudinally-arranged pipes in ships are equipped with loops as a measure to reduce stresses caused by displacement loads conveyed from the hull girder bending and/or thermal loads of carried fluid of non-ambient temperature. But as the loops have some negative effects such as causing extra manufacturing cost and occupying extra space, the number and the dimensions of the loops need to be minimized. In the meanwhile, a design formula for pipe loops has been developed by modeling them as a spring element of which stresses and axial stiffness are calculated based on the beam theory. But as the beam theory turns out to be inappropriate to deal with the complex structural behavior in the curved corner portion of the loop, this paper aims at improving the previously developed design formula by adopting correction factors which can allow for the gap between the results of beam theory and a more accurate analysis. This paper adopts a finite element analysis with two-dimensional shell elements with some validation work for it. The paper ends with a sample application of the proposed formulas showing their accuracy and efficiency.

• ETRI Journal
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• 제44권5호
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• pp.849-858
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• 2022

Dynamic voltage frequency scaling (DVFS) has been widely adopted for runtime power management of various processing units. In the case of neural processing units (NPUs), power management of neural network applications is required to adjust the frequency and voltage every layer to consider the power behavior and performance of each layer. Unfortunately, DVFS is inappropriate for layer-wise run-time power management of NPUs due to the long latency of voltage scaling compared with each layer execution time. Because the frequency scaling is fast enough to keep up with each layer, we propose a layerwise dynamic frequency scaling (DFS) technique for an NPU. Our proposed DFS exploits the highest frequency under the power limit of an NPU for each layer. To determine the highest allowable frequency, we build a power model to predict the power consumption of an NPU based on a real measurement on the fabricated NPU. Our evaluation results show that our proposed DFS improves frame per second (FPS) by 33% and saves energy by 14% on average, compared with DVFS.

• Asia Marketing Journal
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• 제11권2호
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• pp.173-192
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• 2009

As video games gain popularity and become a normal part of home entertainment, concern about youth access to inappropriate games continues to grow. Some people have claimed that violent video games influence children's aggressive behavior and that violent video games have some responsibility for violence in the school. In response to people's concerns, the video game industry created a video game rating system in 1995 to help parents decide which video games are appropriate for their children. This study investigated whether parents were aware of the video game rating system and how often they have used it when selecting video games for their children. This study attempted to find relationships among parents' attitudes toward video games, their guidance styles for their children's video game play, and their use of the video game rating system. This study found that most parents have used the video game ratings very frequently when they select video games for their children. But many parents still don't understand the video game rating system. This study showed that parents who had more negative attitudes or less positive attitudes toward video games were more likely to impose restrictions on their children's video game play and to use the video game rating system as a means to restrict their children's access to violent video games.

• 한국항공운항학회지
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• 제31권3호
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• pp.161-171
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• 2023

The traditional safety management method starts with the misconception that similar accidents will recur if the inappropriate behavior of the person who caused the accident is investigated and punishment is not judged. However, in modern safety management, incidents or situations occur when negative conditions latent in the system are mutually influenced and triggered. The precedent for revoking the disposition of suspension of first officer A of Eastar Jet, which won a legal lawsuit against the administrative regulatory authority, is a representative example that will serve as an opportunity for the administrative regulatory authority to break away from the punishment-oriented safety management method of the past. On the other hand, airmans and air carriers also need to have a clear understanding of flight regulations, and when judicial judgment is required, predictable and effective legal effects can be obtained by preparing clear standards for flight regulations. In addition, administrative regulatory authorities expect a change from the punishment-oriented safety management policy of the past to a systematic safety management policy.

• 보건의료산업학회지
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• 제6권1호
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• pp.39-51
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• 2012

The purpose of this study is to provide a set of fundamental data for the oral hygiene education for the elderly as a result of the survey on the oral hygiene and subjective oral health of the elderly in an aged society. For this purpose, 269 elders who dwelled in Gyeongsangbuk-do region were randomly selected in an arbitrary selection process, followed by a survey on their oral hygiene and health. The collected data were coded and processed by using SPSS 15.0 software. As for the analysis of the data, the general characteristics and the basic items concerning the management of the oral health were analyzed for their frequency and percentages, while the general characteristics and the awareness on the oral health were processed with Chi-square validation to show a set of results as follows; Firstly, among the items on the oral health, the satisfaction on the current condition of their oral health was below average. Secondly, concerning the oral hygienic behaviors, the majority of the samples answered that they were brushing their teeth twice a day. And, as for the brushing methods, the largest number of the samples answered that they were brushing their teeth in a 'horizontal direction'. Thirdly, they reported they were having difficulties in getting dental treatments. The implications of this study are that it is necessary to provide sound oral health education to them to correct the inappropriate oral hygienic behaviors.

• 한국안전학회지
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• 제33권1호
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• pp.66-72
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• 2018

This study analyses the types, related operations, facilities, and causes of chemical accidents in Korea based on the RISCAD classification taxonomy. In addition, human error analysis was carried out employing different human error classification criteria. Explosion and fire were major accident types, and nearly half of the accidents occurred during maintenance operation. In terms of related facility, storage devices and separators were the two most frequently involved ones. Results of the human error-based analysis showed that latent human errors in management level are involved in many accidents as well as active errors in the field level. Action errors related to unsafe behavior leads to accidents more often compared with the checking behavior. In particular, actions missed and inappropriate actions were major problems among the unsafe behaviors, which implicates that the compliance with the work procedure should be emphasized through education/training for the workers and the establishment of safety culture. According to the analysis of the causes of the human error, the frequency of skill-based mistakes leading to accidents were significantly lower than that of rule-based and knowledge based mistakes. However, there was limitation in the analysis of the root causes due to limited information in the accident investigation report. To solve this, it is suggested to adopt advanced accident investigation system including the establishment of independent organization and improvement in regulation.