• 대한기계학회논문집A
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• 제26권11호
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• pp.2415-2420
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• 2002

In the present study, a new anchor design was proposed to minimize the initial deflection of micro multi-layer cantilever beam with step-up structure, which is a key component of thin film micro-mirror array. It is important to minimize the initial deflection, caused by residual stress, because it reduces the performance of the actuation. Theoretical and experimental studies were conducted to examine the cause of the initial bending deflection. It was found that the bending deflection at the anchor of the cantilever beam was the primary source of initial deflection. Various anchor designs were proposed and the initial deflections for each design were calculated by finite element analysis. The analysis results were compared with experiments. To reduce the initial deflection a secondary support was added to the conventional structure. The optimal shapes were obtained by simulation and experiment. It was found from the analysis that the ratio or horizontal and vertical dimensions of secondary support was the governing factor, which affected the initial deflection.

• 지역사회간호학회지
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• 제13권1호
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• pp.98-114
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• 2002

Purpose: This review examined literature relevant to adolescent's health behavior in order to identify key behaviors and factors related to health behaviors for targeting health promotion interventions. Method: A critical review of 29 research articles was carried out using the guidelines suggested by Cooper. Result: The majority of the studies were descriptive and cross-sectional. Generally. the study includes sub-dimensions such as general hygiene and daily life habit, safety and accident prevention, nutrition and eating (tobacco, drinking), exercise, mental health and stress management, health duty (drug, health examination, disease prevention). Factors highly related to health behaviors were age, living areas, economic status, parent health behaviors, parent health concern, social support, friends influence, self-efficacy, self-esteem, locus of control, and the perceived health status. Sex, parent education and health knowledge were not related to health behaviors of adolescents. Conclusion: Several conceptual and methodological problems were identified in the studies review, such as restricted conceptualization of health behaviors and sampling issues which limit the generalizability of the study outcomes. Further research is needed to enhance the concept clarification and generalizablity of the study results.

• 한국전자통신학회논문지
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• 제15권5호
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• pp.939-948
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• 2020

가상현실 기술을 농업 기술 교육에 접목하려는 많은 노력이 이루어지고 있으며, 농기계 교육과 같은 직접적인 교육뿐만 아니라 게임을 이용한 간접 교육에도 관심이 증가하고 있다. 가상현실에서 핵심적인 기술은 사용자가 실제와 같이 느낄 수 있게 대상을 모델링하는 것이다. 농장에서 재배하는 농작물은 농장의 환경에 따라 동일한 영향을 받는다. 또한, 농작물은 각각 독립적인 특성도 가지게 된다. 본 논문에서는 농작물 모델링의 이러한 특성을 반영하여 NPC 형태로 모델링하는 방법을 제안한다. 제안하는 방법에서는 개별 농작물이 날씨와 농장의 특성을 반영하는 방법과 독립적인 특성을 반영하는 방법을 구현한다. 구현 결과는 제안하는 방법이 간단한 알고리즘을 사용하지만 농작물을 매우 사실적으로 표현하는 것을 보여준다.

• 품질경영학회지
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• 제32권4호
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• pp.92-102
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• 2004

In this era of intense competition, TQM has become the key program in organizations as they strive for a competitive advantage. It has been applied to manufacturing and service sector since BNQA model was established in 1987. TQM literature for manufacturing sector abounds with empirical studies on the critical dimensions of TQM, but there is few empirical studies on the TQM evaluation for service sector. In this paper, two methodologies are applied to evaluate the TQM activities of service companies comparatively One of them is the traditional scoring system(TSS) by analytic hierarchy process(AHP). The other is the efficiency measuring system(EMS) by data envelopment analysis(DEA). DEA outperformed other alternative methods to measure the efficiency and it can be applied to evaluate the TQM activities. The objective of this paper is to evaluate TQM activities of domestic service companies by applying TAE(Total quality management Activities Evaluation) model to them. The result of this study is that TSS scores are not significantly correlated with EMS scores. It means that service organizations must not only make efforts to get the higher scores in terms of TSS but also take necessary steps to enhance their efficiencies.

• 대한기계학회논문집A
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• 제33권10호
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• pp.1108-1118
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• 2009

A Very High Temperature Gas Cooled Reactor (VHTR) has been selected as a high energy heat source of the order of $950^{\circ}C$ for nuclear hydrogen generation, which can produce hydrogen from water or natural gas. A primary hot gas duct (HGD) as a coaxial double-tube type cross vessel is a key component connecting a reactor pressure vessel and an intermediate heat exchanger in the VHTR. In this study, a structural sizing methodology for the primary HGD of the VHTR is suggested in order to modulate a flow-induced vibration (FIV). And as an example, a structural sizing of the horizontal HGD with a coaxial double-tube structure was carried out using the suggested method. These activities include a decision of the geometric dimensions, a selection of the material, and an evaluation of the strength of the coaxial double-tube type cross vessel components. Also in order to compare the FIV characteristics of the proposed design cases, a fluid-structure interaction (FSI) analysis was carried out using the ADINA code.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1265-1270
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• 2007

Conventional methods for fabricating three-dimensional (3-D) scaffolds have substantial limitations. In this paper, we present 3-D scaffolds that can be made repeatedly with the same dimensions using a microstereolithography system. This system allows the fabrication of a pre-designed internal structure, such as pore size and porosity, by stacking photopolymerized materials. The scaffolds must be manufactured in a material that is biocompatible and biodegradable. In this regard, we synthesized liquid photocurable biodegradable TMC/TMP, followed by acrylation at terminal ends. And also, solidification properties of TMC/TMP polymer are to be obtained through experiments. Cell adhesion to scaffolds significantly affects tissue regeneration. As a typical example, we seeded chondrocytes on two types of 3-D scaffold and compared the adhesion results. Based on these results, the scaffold geometry is one of the most important factors in chondrocyte adhesion. These 3-D scaffolds could be key factors for studying cell behavior in complex environments and eventually lead to the optimum design of scaffolds for the regeneration of various tissues, such as cartilage and bone.

• ALGAE
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• 제27권4호
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• pp.225-234
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• 2012

Zygnema is a conjugating filamentous green algal genus that is distributed in a broad range of freshwater habitats, from sea level to alpine summits. Although more than 150 species have been described worldwide, their taxonomy remains unclear, probably owing to their relatively simple morphology. We investigated the detailed morphology of Korean Zygnema species, combined with analysis of the plastid psbA gene from 22 specimens of the genus and putative relatives, in order to develope a key to their identification and isolation, and to determine their relationships. We recognized two species of Zygnema; Z. insigne and Z. leiospermum, based on morphological characters such as width of the vegetative cell, position of zygospores, dimensions and form of spores, shape of female gametangia, and color of mesospores. The analysis of psbA data was consistent with morphological comparison. The pairwise divergence between two species was 3.7-4.1% (34-38 bp) in psbA sequences. The phylogeny of psbA revealed the monophyly of Z. insigne and Z. leiospermum together with two isolates of Z. circumcarinatum from Germany and Scotland. This is the first report on the psbA gene phylogeny of Zygnema.

• Architectural research
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• 제17권4호
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• pp.139-146
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• 2015

In 2007, in the city of Chongqing, the city government announced a plan to meet the basic needs of its lower-to-middle class residents, namely those of providing a shelter and urban infrastructure. In one respect, the effort to attain such goals has achieved good quantitative results; however, a more critical examination reveals that little consideration has been given to analyzing the qualitative aspects of such a policy, namely the physical and emotional effects on tenants. The results of the research in this paper have implications on the need to focus on building a 'sustainable' and 'healthy' community, with the awareness that for people in low-rent areas, sociability and community spirit are more closely related to their neighborhood contentment. Although attention to scale and type of area-planning are both important, the immediate surroundings and services are often neglected, but as we shall show they are key considerations for residents in this new type of housing. While attempting to comprehend the role of community in the quality of a neighborhood, in this research, we attempt to document the physical appearance of the problem and explore its underlying causes in order to shed more light on residents' individual evaluations of quality in their local living conditions and include the affective dimensions of such perceptions.

• Structural Engineering and Mechanics
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• 제46권2호
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• pp.197-212
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• 2013

With more and more high-rise building being constructed in recent decades, bluff body flow with high Reynolds number and large scale dimensions has become an important topic in theoretical researches and engineering applications. In view of mechanics, the key problems in such flow are high Reynolds number turbulence and fluid-solid interaction. Aiming at such problems, a parallel fluid-structure interaction method based on socket parallel architecture was established and combined with the methods and models of large eddy simulation developed by authors recently. The new method is validated by the full two-way FSI simulations of 1:375 CAARC building model with Re = 70000 and a full scale Taipei101 high-rise building with Re = 1e8, The results obtained show that the proposed method and models is potential to perform high-Reynolds number LES and high-efficiency two-way coupling between detailed fluid dynamics computing and solid structure dynamics computing so that the detailed wind induced responses for high-rise buildings can be resolved practically.

• 한국도서관정보학회지
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• 제32권2호
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• pp.269-288
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• 2001

문헌정보학의 발전과정을 살펴보면 문헌정보학 연구가 사회과학의 전반적 변화에 적절하게 대응하지 못하였음을 알 수 있다. 일례로 다른 사회과학분야의 다양한 방법론적 실험에 대하여, 우리 분야에서는 여전히 실증주의적 연구경향이 지배적 영향력을 행사하고 있음을 지적할 수 있다. 이 글은 문헌정보학 연구가 우리사회에서 문헌정보학적 설명을 필요로 하는 다양한 여러 가지 키워들을 분석하고 해석하는 데 일익을 담당하여야 한다는 점을 밝힌다. 그 한 예로 최근에 우리 분야에서도 관심의 대상이 되고 있는 담론분석의 응용가능성과 유용성을 논증한다. 이를 위하여 우리 분야에 있어서 연구의 성격을 결정지은 역사적 배경을 고찰하고, 담론분석의 간략한 전개양상과 담론분석의 일반적인 원칙들을 살펴본 후, 문헌정보학에 있어서 이러한 관점의 적용가능성을 가늠한다