• 에너지공학
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• 제2권3호
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• pp.285-292
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• 1993

A cylindrical-shape, horizontal furnace was used to investigate the effect of particle size on the pulverized coal combustion behavior. Three differently-sized fractions (5, 30, and 44 microns in average diameter) of high-volatile bituminous coal, were burned in the test furnace. Ignition characteristics of pulverized coal flame were determined through the amount of methane in the carrier gas for the self-sustaining flame. Easiest ignition occurred with the immediately-sized coal particles. Ignition of coal jet flame appeared to occur through a gas-phase homogeneous process for particles larger than 30 microns. Below this limiting size, heterogeneous process probably dominated ignition of coal flame. Oxygen concentration of combustion air was varied up to 50%, to determine the oxygen-enrichment effect on the coal ignition behavior. Oxygen enrichment of primary air assisted ignition behavior of pulverized coal flame. However, enrichment of secondary air didn't produce any effect on the ignition behavior.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2002년도 제24회 KOSCO SYMPOSIUM 논문집
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• pp.171-178
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• 2002

Numerical simulations of the condition in the iron ore sintering bed are performed for various parameters. The sintering bed is modelled as an unsteady one-dimensional progress of solid material, containing cokes and iron ore. Bed temperature, solid mass and gas species distributions are predicted for various parameters of moisture contents, cokes contents and air suction rates, along with the various particle diameters of the solid for sensitivity analysis. Calculation results show that influences of these parameters on the bed condition should be carefully evaluated for achievement of the self-sustaining combustion without the high temperature section, which can cause the excessive melting in the bed. It suggests that the model should be extended to consider the bed structural change and multiple solid phase, which can treat the inerts and fuel particles separately.

• International journal of advanced smart convergence
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• 제9권3호
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• pp.153-160
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• 2020

This research aims to provide empirical basic data for the development of local communities through the establishment of efficient strategies for the formation of positive relations between the club and the region through the Creation of Shared Value (CSV) activities. We come up with the results of this study to show that CSV, social problem orientation, and core competency utilization affect the team trust of local community, and that CSV, long-term orientation, social problem orientation and core competency utilization affect community identification. The research should enhance the value of professional sports teams that promote their own path to self-sustaining as a single independent business area, and identify their trust through CSV activities for co-prosperity with their local communities, and thus their relationship with the community. Therefore, various strategies and efforts will ultimately increase the team trust and community identity of local residents in professional volleyball teams, while at the same time gaining positive effects on professional volleyball teams.

• 성인간호학회지
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• 제24권6호
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• pp.607-614
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• 2012

Purpose: This is a descriptive research that reports incidents of workplace violence among care helpers. Methods: The subjects were 181 care helpers from elderly care facilities and domiciliary elderly welfare centers in Daejeon. Data were collected through self-administered questionnaires from July to November 2011. Subjects were asked to report incidents of violence within the previous six months. Data analysis included one-way ANOVA, and logistic regression analysis. Results: Forty-seven percent of care helpers reported verbal violence, 16% reported being physically threatened, more than 21 % reported sustaining a physical injury with 2% reporting severe physical injuries. Further, 18.8% of the care givers reported being sexually harassed by client. There were differences in reported workplace violence based on service types, service hours and whether there were policies about workplace violence. Conclusion: To prevent workplace violence for carehelpers, it is necessary to make a policy for preventing violence and develop a violence prevention program to meet service characteristics of facility-based and domiciliary care helpers.

• 항공우주시스템공학회지
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• 제7권4호
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• pp.55-61
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• 2013

In recent years, NASA, FAA and the aerospace industry, through MIL-HDBK-17 and the NASA-conceived AGATE(Advanced General Aviation Transport Experiments) program, have worked together to reduce the qualification burden imposed on individual aircraft manufacturers. AGATE is one of the most successful public/private cost-haring partnerships ever conceived, bringing together academia, the FAA, other government agencies and industry to develop affordable new technologies and accompanying industry standards and certification methods. In 2005, NASA established NCAMP(National Center for Advanced Materials Performance) with the purpose of refining and enhancing the AGATE process to a self-sustaining level to serve the entire aerospace industry in partnership with CMH-17, FAA, and SAE. In this paper, I will introduce briefly NCAMP process and explain its organization structure and core NCAMP documents. This paper can provide some help in establishing our certification system for composite materials where the NCAMP process is expected to be the most good model.

• 한국임상보건과학회지
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• 제6권2호
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• pp.1097-1105
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• 2018

Purpose: Loneliness is an extremely subjective experience that is influenced by life experiences and circumstances. This study attempted to provide basic data for the development of nursing intervention strategies to understand the concept of loneliness and to reduce loneliness on various topics. Methods: The research analysis method is based on the framework of concept analysis proposed by Walker and Avant (1988). Results: The results of this study are as follows: 1) Self-alienation 2) Isolation of human beings 3) Psychological damage reaction 4) Pain 5) Loneliness is the loss of a comfortable "frame". The prerequisites can be divided into personal characteristics and situational characteristics. Empirical criteria include intimate others, lack of social relationships or problems, family and friendship, belonging, recognition or expression of loneliness, emotional state changes and changes in health behavior, and physical symptoms. Conclusions: Loneliness is an important indicator of well-being and a cause of physical and mental illnesses, so nurses facing various subjects should be able to recognize the signs and symptoms of loneliness. By promoting and sustaining their interest, they should be able to enjoy lonely people.

• Nuclear Engineering and Technology
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• 제50권8호
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• pp.1339-1348
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• 2018

The aim of this paper is to determine neutronic performances of the light water reactor (LWR) spent fuel mixed with fertile thorium fuel in a FFHR. Time dependent three dimensional calculations for major technical data, such as blanket energy multiplication, tritium breeding ratio, cumulative fissile fuel enrichment and burnup have been performed by using Monte Carlo Neutron-Particle Transport code MCNP5 1.4, coupled with a novel interface code MCNPAS, which is developed by our research group. A self-sustaining tritium breeding ratio (TBR>1.05) has been kept throughout the calculations. The study has shown that the fissile fuel quality will be improved in the course of the transmutation of the LWR spent in the FFHR. The latter has gained the reusable fuel enrichment level conventional LWRs between one and two years. Furthermore, LWR spent fuel - thorium mixture provides higher burn-up values than in light water reactors.

• East Asian mathematical journal
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• 제39권2호
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• pp.119-139
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• 2023

Most of calculus and real analysis are concerned with the study on continuous functions. Because of self-sustaining concept caused by everyday language, continuity has difficulties. This kind of viewpoint is strengthened with that teacher explains continuity by graph drawn ceaselessly and so finally confused with mathematics concept which is continuity and connection. Thus such a concept image of continuity becomes to include components which create conflicts. Therefore, we try to analyze understanding of continuity on university students by using the concept image as an analytic tool. We survey centering on problems which create conflicts with concept definition and image. And we investigate that difference of definition in continuous function which handles in calculus and analysis exists and so try to present various results on university students' understanding of continuity concept.

• 생명과학회지
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• 제22권8호
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• pp.999-1008
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• 2012

자기 현가적(self-sustaining) 조절 장치인 생체시계는 24시간 주기의 생체리듬을 조절하며 또한 생물체로 하여금 매일 변화하는 자연환경의 외부 신호를 인지할 수 있도록 해준다. 생체시계 유전자의 발현 조절은 전사/해독의 역환류 기작을 통해 이루어진다. 애기장대 LATE ELONGATED HYPOCOTYL (LHY)와 CIRCADIAN CLOCK-ASSOCIATED 1 (CCA1)는 아침에 최고조로 발현되며 해독된 LHY and CCA1는 저녁에 최고로 발현되는 TIMING OF CAB EXPRESSION1 (TOC1)의 발현을 억제한다. TOC1단백질은 LHY와 CCA1 발현을 촉진시킴으로써 생체시계의 핵심 진자(oscillator)를 형성한다. 동물에서 생체시계의 주요 전사 인자인CLOCK은 아세틸화효소 활성 기능을 가지며, 이는 생체시계의 기능 유지에 아세틸화의 중요함을 의미한다. 하지만 애기장대 생체시계에 아세틸화를 담당하는 인자에 대한 정보는 현재 보고된 바가 없다. 본 연구에서 DET1 (De-Etiolated1)는 암조건하에서 애기장대 생체시계 관련 핵심인자 중 하나인 LHY발현을 억제하는데 필요하며 이의 억제는 H3Ac 조절을 통해 이루어짐을 증명하였다. 하지만 LHY 아세틸화를 담당하는 효소의 발굴 및 이들 효소와 DET1과의 연결을 찾는 문제는 여전히 미재로 남아있다.

• Nutrition Research and Practice
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• 제15권5호
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• pp.639-654
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• 2021

BACKGROUND/OBJECTIVES: Many adolescents in developing countries skip breakfast. Innovative nutrition education (NE) strategies are needed to enhance knowledge and skills related to the breakfasts of adolescents in a low socioeconomic setting. The objective was to evaluate short- and long-term effects of a multi-strategy, school-based NE intervention on adolescents' breakfast-related personal influences and behaviors. SUBJECTS/METHODS: An intervention study with a cluster randomized controlled trial design was conducted in 4 senior high schools in Makassar, Indonesia. The multi-strategy NE intervention was delivered for 3 months. Data were collected using a self-administered questionnaire and a 3-day breakfast recall (face-to-face interview). Wilcoxon, McNemar, and Mann-Whitney tests were used to determine intra- and intergroup differences. RESULTS: Unlike knowledge, improvement was observed in attitude and self-efficacy scores in the intervention groups (IGs) (P < 0.01); however, no significant changes were observed in the control group (CG). More students showed improved motivation in the IG than in the CG (P > 0.05). Changes in breakfast frequency and macronutrient intake from breakfast were greater in the IG than in the CG (P < 0.05). CONCLUSIONS: A multi-strategy NE intervention is effective in producing positive changes in breakfast-related attitude, self-efficacy, and motivation of adolescents from a low-middle socioeconomic setting. The intervention improved breakfast frequency and nutrient intake. This intervention has promise for sustaining the observed changes over the long-term.