• Nuclear Engineering and Technology
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• 제45권4호
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• pp.459-468
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• 2013

During a station blackout (SBO), the initiating event is a loss of Class IV and Class III power, causing the loss of the pumps, used in systems such as the primary heat transporting system (PHTS), moderator cooling, shield cooling, steam generator feed water, and re-circulating cooling water. The reference case of the SBO case does not credit any of these active heat sinks, but only relies on the passive heat sinks, particularly the initial water inventories of the PHTS, moderator, steam generator secondary side, end shields, and reactor vault. The reference analysis is followed by a series of sensitivity cases assuming certain system availabilities, in order to assess their mitigating effects. This paper also establishes the strategies to mitigate SBO accidents. Current studies and strategies use the computer code of the Integrated Severe Accident Analysis Code (ISAAC) for Wolsong plants. The analysis results demonstrate that appropriate strategies to mitigate SBO accidents are established and, in addition, the symptoms of the SBO processes are understood.

• Journal of Applied and Pure Mathematics
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• 제4권1_2호
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• pp.27-36
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• 2022

An innovation diffusion model is proposed model consists of three classes, namely, a non-adopter class, adopter class innovation-I, and adopter class innovation-II in a partially competitive and cooperative market. The proposed model is analyzed with the help of the qualitative theory of a system of ordinary differential equations. Basic influence numbers associated with first and second innovation $R_{0_1}$ and $R_{0_2}$ respectively in the absence of each other are quantified. Then the overall basic influence number (R₀) of the system is assessed for analyzing stability in the market in different situations. Sensitivity analysis of basic influence numbers associated with first and second innovation in the absence of each other is carried out. Numerical simulation supports our analytical findings.

• Nuclear Engineering and Technology
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• 제56권4호
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• pp.1320-1329
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• 2024

When wall-thinning occurs in nuclear Class 2 and 3 pipes, reinforcement is typically applied rather than replacement. To analyze the structural integrity of reinforced wall-thinned pipe, stress analysis results using full 3-D FE analysis are not compatible to the design code equation, ASME BPVC Sec. III NC/ND-3650. Therefore, the efficient stress evaluation method for the reinforced wall-thinned pipe, compatible to the design code equation, needs to be developed. In this paper, stress evaluation methods for the reinforced wall-thinned pipe are proposed using the equivalent straight pipe concept. Furthermore, for fatigue analysis of the reinforced wall-thinned pipe, the stress intensification factor of reinforced wall-thinned pipe is presented using the structural stress method given in ASME BPVC Sec. VIII Div.2.

• 한국정보처리학회논문지
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• 제2권4호
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• pp.477-486
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• 1995

본 논문에서는 이산수학에서 많이 다루고 있는 Galois-격자를 이용하여 객체지향 분석 모델을 구축하고 이를 유지 보수하기 위한 방법들을 제시하고, 예를 통해 객체 지향분석 모델을 구축하는 것에 대해 분석하였다. 클래스 객체들과 그들 사이에 형성 된 속성을 이항관계로 표현한 Galois-격자를 이용하여 관계(relation)를 정립하고, 분 석단계의 클래스 계층구조에 새로운 클래스 노드를 추가할 때마다 Galois-격자구조를 점증적으로 갱신하는 알고리즘을 제안하였다. 이러한 제안은 실험을 통하여 새로운 클 래스 노드의 추가는 일정한 시간내에 수행됨을 알았으며, 격자구조의 성장 속도는 클 래스 노드수와 비례하며, 클래스 노드에 관련된 속성의 수가 상한치를 갖을 때 알고리 즘의 최악경우 복잡도는 객체수에 따라 선형적으로 증가함을 보였다. 이 결과는 객체 지향 분석 모델의 이해도와 모델의 유지수하는 추적도를 높이고, 객체지향 시스템의 장점인 클래스의 재사용 가능성을 향상시키고 클래스 계층 유지보수를 실질적으로 지 원한다.

• 한국초등수학교육학회지
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• 제15권2호
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• pp.385-415
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• 2011

본 연구는 초등수학영재 수업에서 일어나는 교사와 학생간의 언어적 의사소통을 살펴보면서 수업 중 교사와 학생의 발언 흐름과 수학적 의사소통이 활발히 일어나는 상황에서의 교사 발언 유형의 분석을 통해 효과적인 수학적 의사소통의 언어흐름을 제안하는 것을 목적으로 한다. 이를 위해 Flanders 언어상호작용분석 프로그램으로 수학영재지도의 현장 교육 경력이 많고 수학영재교육분야의 전문가 추천을 받은 한 명의 우수 교사의 수업 사례를 분석하였다. 연구 결과 일반 학급 수업에서의 경향과 다른 양태였으며, 수학적 의사소통의 수준이 높고 활발하게 일어나는 과정은 대부분 (질문)${\rightarrow}$(활동 및 사고 대기)${\rightarrow}$(넓은 답변)${\rightarrow}$(활동)의 언어 흐름 형태였으며, 수학적 의사소통을 가장 활발하게 하는 교사 발언의 유형은 비지시적 발언 중 '아이디어 수용'인 것으로 나타났다. 이를 바탕으로 영재학급에서의 효과적인 언어 상호작용의 흐름을 제안하였다.

• 한국콘텐츠학회논문지
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• 제16권11호
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• pp.594-604
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• 2016

본 연구는 방송통신대학 간호학 전공과정 간호사를 대상으로 수업만족도, 학업적 자기효능감, 자기주도적 학습능력을 확인하고 자기주도적 학습능력에 미치는 영향을 파악하고자 수행하였다. 자료수집은 학업을 병행하고 있는 방송통신대학 간호학 전공 과정에 있는 간호사 231명을 대상으로 하였다. 자료분석은 퉁계분석 프로그램을 이용하여 기술통계, 상관관계분석, 다중회귀분석을 이용하였다. 연구결과 방송통신대학 간호학 전공 과정 간호사의 수업만족도 및 자기주도적 학습능력, 학업적 자기효능감 간에는 모두 유의한 양의 상관관계가 있는 것으로 나타났으며, 수업만족도와 자기주도적 학습능력은 학업적 자기효능감에 영향을 미치는 요인으로 파악되었다. 이에 본 연구 결과가 방송통신대학 간호학 전공과정 간호사의 자기주도적 학습능력 향상 프로그램 개발의 근거 자료로 활용될 수 있을 것으로 기대하며, 개발된 교육 프로그램의 타당성과 효과성을 분석하는 중재 연구 또한 필요함을 제안한다.

• 대한미생물학회지
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• 제21권2호
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• pp.171-179
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• 1986

The HLA class II region encodes a series of polymorphic glycoproteins that form cell surface heterodimers each consisting of one $\alpha$ and one $\beta$ chain. Thess class II molecules are encoded by genes clustered within three loci. DP, DQ, and DR are functfonally implicated as regulatory signals in intercellular communication during the immune resposes. The phenotypic hallmark of the HLA complex is a high degree of structural and functional polymorphism. Detailed analysis. of such polymorphisms should aid in understanding the molecular basis for associations between HLA and diseases. We have used techniques of restriction enzyme fragment analysis by Southern blotting to investigate polymorphisms associated with DQ $\beta$ class II genes on haplotypes expressing the HLA-DR4 and -DQw3 specificities. The endonucleases Hind III and Bam HI were used to identify a specific DQ $\beta$ genomic polymorphism that precisely corrresponds with the reactivity of a monoclonal antibody A-10-83, previously shown to define a serologic split of DQw3. This study identifies two allelic DQ va. riants. DQw3.1 and DQw3.2. We used these specific genotypic markers to investigate the genomic basis of the association of DR4 with insulin-dependent diabetes mellitus(IDDM) and seropositive juvenile rheumatoid arthritis(JRA). The DR4 positive IDDM demonstrate the predominant expression of DQw3.2 and the very rare expression of DQw3.l. However, in haplotype matched siblings from two IDDM families, all of the DR4 positive siblings display a IDDM-associated DQw3.2 allele. Thus, both affected and healthy individuals can carry the same haplotypes and genomic markers, demonstrating that thess specific allelic variants are genetic elements that indicate a increased risk of IDDM but are not in fact disease specific. We contrasted this result with a similar analysis of patients with another DR4-associated disease, JRA. In contrast to the preponderance of the DQw3.2 allele in IDDM, the JRA patients expressed either the DQw3.1 or the DQw3.2 allele and sometimes both, without apparent association with disease expession. The different genomic markers reported here within HLA-DQ region potentially an analysis of HLA-associated function and disease susceptibility.

• 한국식품영양학회지
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• 제31권2호
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• pp.284-292
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• 2018

This study was conducted to determine the elements that are required and that need improvement in the contents of dietary life education and the educational environment by analyzing the importance-satisfaction of a dietary life education program for dietary life education trainees. The results of the rank test for the satisfactory elements of dietary life education were in the order of competence of instructors, educational contents, time of education, educational environment and affordability of tuition. The importance-satisfaction analysis of the contents and construction of the dietary life education program showed that "suitable contents for the theme of the class", "contents and construction of practice class", "diversity of practice menu" and "diversity of educational contents" had high importance and satisfaction scores and therefore, could be maintained at their current levels. Meanwhile, "adequacy of class time" and "contents and construction of theory class" showed low importance and satisfaction scores, requiring a little effort. Whereas, "time and construction of group practice", "structure of textbook for class" and "duration of course and number of classes" showed relatively low satisfaction compared to importance, requiring major efforts for improvement. Similarly, analysis of the lecture element from dietary life education showed that "professional lecture by instructors", "lectures suitable for themes" and "lecture applicable in real life" had relatively low satisfaction compared to importance, requiring major efforts for improvement. In addition, analysis of the educational environment from dietary life education showed that "adequacy of lecture room space", "cooking equipment", "diversity of cooking utensils" and "sanitary condition of cooking utensils" also require major efforts for improvement. Therefore, dietary life education should not be executed with a simple delivery of knowledge but with both theory and practice classes to increase its application in real life, and active and specific efforts are required to nurture professional instructors and establish educational strategies.

• 대한치과교정학회지
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• 제42권4호
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• pp.190-200
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• 2012

Objective: The displacement of the hyoid bone (HB) is a critical biomechanical component of the swallowing function. The aim of this study was to evaluate the swallowing-induced vertical and horizontal displacements of the HB in subjects with 2 different magnitudes of skeletal Class III malocclusion, by means of real-time, balanced turbo-field-echo (B-TFE) cine-magnetic resonance imaging. Methods: The study population comprised 19 patients with mild skeletal Class III malocclusion, 16 with severe skeletal Class III malocclusion, and 20 with a skeletal Class I relationship. Before the commencement of the study, all subjects underwent cephalometric analysis to identify the nature of skeletal malformations. B-TFE images were obtained for the 4 consecutive stages of deglutition as each patient swallowed 10 mL of water, and the vertical and horizontal displacements of the HB were measured at each stage. Results: At all stages of swallowing, the vertical position of the HB in the severe Class III malocclusion group was significantly lower than those in the mild Class III and Class I malocclusion groups. Similarly, the horizontal displacement of the HB was found to be significantly associated with the severity of malocclusion, i.e., the degree of Class III malocclusion, while the amount of anterior displacement of the HB decreased with an increase in the severity of the Class III deformity. Conclusions: Our findings indicate the existence of a relationship between the magnitude of Class III malocclusion and HB displacement during swallowing.

• 한국통신학회논문지
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• 제21권3호
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• pp.629-642
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• 1996

ATM switch handles the traffic for a wide range of appliations with different QOS(Quality-of-Service) requirements. In ATM switch, the priority control mechanism is needed to improve effectively the required QOS requirements. In this paper, we propose a priority control mechanism using the cell transfer ratio type and discard threshold in order to archive the cell loss probability requirement and the delay requirement of each service class. The service classes of our concern are the service class with high time priority(class 1) and the service class with high loss priority control mechanism, cells for two kind of service classes are stored and processed within one buffer. In case cells are stored in the buffer, cells for class 2 are allocated in the stored and processed within one buffer. In case cells are stored in the buffer, cells for class 2 are allocated in the shole range of the buffer and cells for class 1 are allocated up to discard threshold of the buffer. In case cells in the buffer are transmitted, one cell for class 1 is transmitted whenever the maximum K cells for class 2 are transmitted consecutively. We analyze the time delay and the loss probability for each class of traffic using Markov chain. The results show that the characteristics of the mean cell delay about cells for class 1 becomes better and that of the cell loss probability about cells for class 2 becomes better by selecting properly discard threshold of the buffer and the cell transfer ratio according to the condition of input traffic.