• 한국공간구조학회논문집
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• 제15권4호
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• pp.107-114
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• 2015

Large spatial structures can not easily predict the dynamic behavior due to the lack of construction and design practices. The spatial structures are generally analyzed through the numerical simulation and experimental test in order to investigate the seismic response of large spatial structures. In the case of analysis for seismic response of large spatial structure, the many studies by the numerical analysis was carried out, researches by the shaking table test are very rare. In this study, a shaking table test of a small-scale arch structure was conducted and the dynamic characteristics of arch structure are analyzed. And the dynamic characteristics of arch structures are investigated according to the various column cross-section and length. It is found that the natural vibration periods of the small-scaled arch structure that have large column stiffness are very similar to the natural vibration period of the non-column arch structure. And in case of arch structure with large column stiffness, primary natural frequency period by numerical analysis is very similar to the primary natural frequency period of by shaking table test. These are because the dynamic characteristics of the roof structure are affected by the column stiffness of the spatial structure.

• International Journal of Costume and Fashion
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• 제7권1호
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• pp.1-10
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• 2007

The Italian fashion industry has achieved a remarkable success in the global market with the distinctive features of its industry structure and product quality, and such a system has been subject to many researches. Especially, the retail structure centered on small speciality retail stores rather than the industry structure of medium and small sized companies and department stores is thought to be the most noticeable distinctive feature that differentiates the Italian fashion industry from other countries. This system is thought to be a driving force behind the continuous development and innovation closely associated with the market. In result, As medium and small size companies are the center of the Italian fashion industry, advantages of small companies based on region, that is, flexibility and innovation of medium and small size companies, close cooperation between companies are utilized and it has been progressing closely with the Italian traditional culture and being modernized based on traditional technological skills.

• 한국콘텐츠학회논문지
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• 제19권3호
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• pp.539-547
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• 2019

본 연구의 목적은 팀 프로세스의 작은 세상 구조가 팀 성과에 미치는 영향을 탐색적으로 살펴보는 것이다. 관련 문헌을 고찰하여 팀 프로세스의 작은 세상 구조와 팀 성과 사이의 관계를 이론적으로 논의하였으며, 축구팀의 패스 데이터를 이용하여 실증적으로 분석하였다. 2014년 브라질 월드컵 경기의 패스 데이터를 수집하여 128개의 패스 네트워크를 구성하고 작은 세상을 나타내는 구조적 특성을 측정하였다. 이 과정에서 작은 세상의 정도를 측정하는 데 폭넓게 사용된 작은세상지수(small-world index)의 단점을 극복할 수 있는 새로운 지수를 개발하였다. 그리고 작은 세상 구조와 성과 사이의 관계를 밝히기 위하여 상관분석과 회귀분석을 실시하였다. 분석 결과에 의하면, 팀 프로세스의 군집성은 팀 성과와 지수함수의 관계가 있고 팀 프로세스의 연결성은 팀 성과와 로그함수의 관계가 있는 것으로 나타났다. 결과적으로 팀 프로세스의 작은 세상 구조는 팀 성과에 긍정적인 영향을 미치는 것으로 나타났다. 이론적 논의와 실증적 분석을 통해, 본 연구는 팀 프로세스의 작은 세상 구조가 팀원 사이의 업무 조정과 협업을 촉진하는데 효과적으로 작용하여 팀 성과에 긍정적인 영향을 미친다는 것을 밝혀내었다.

• 천문학회보
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• 제39권2호
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• pp.82-82
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• 2014

One of the subjects in clouds' structure and development is small scale structure of interstellar cloud. The possibility of AU scale structure (Marscher et al. 1993; Moore & Marscher 1995; Roy et al. 2012) is discussed, and this small scale structure is considered as the result of hydrogen volume density (Moore & Marscher 1995), or small-scale chemical and other inhomogeneities (Liszt & Lucas 2000). In order to study this subject with emission line, extremely high resolution is mandatory by VLBI system. However, the alternative method could be observing the absorption line of interstellar cloud on the continuum object. In this case, the resolution would be restricted to the size of the continuum object, if the size of the object is smaller than the resolution of a used telescope. We observed the previous researchers' three objects (BLLAC, NRAO150, B0528+138), whose spectrums are changed from 1993 to 1998 (Liszt & Lucas 2000), with KVN. Through KVN observation, we found the changes of optical depth spectrum compared with the previous spectrums. We will discuss the optical depth spectrum variation by time variation and the meaning of it.

• 한국재료학회지
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• 제1권2호
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• pp.86-92
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• 1991

Morse potential을 변형한 2체항(2-body tem)과 Axilrod-Teller potential을 변형한 3체항(3-body tem)으로 구성된 포텐셜에너지 함수를 사용하여 $C_2-C_6$ cluster 동소체들의 에너지들의 에너지를 3체항 세기인자(3-body intensity factor)의 함수로 나타냄으로써 3체 인력의 기여도의 증가함에 따라 carbon cluster들의 구조는 open structure로부터 closed structure로, 또한 복잡한 구조로부터 단순한 구조, 즉 3차원적인 형태로부터 2차원 및 1차원적인 형태로 변해감을 알 수 있었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.2833-2838
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• 2007

Recently, small hydropower attracts attention because of its clean, renewable and abundant energy resources to develop. However, suitable turbine type is not determined yet in the range of small hydropower and it is necessary to study for the effective turbine type. Moreover, relatively high manufacturing cost by the complex structure of the turbine is the highest barrier for developing the small hydropower turbine. Therefore, a cross-flow turbine is adopted because of its simple structure and high possibility of applying to small hydropower. The purpose of this study is to examine the optimum configuration of nozzle shape to further optimize the cross-flow hydraulic turbine structure and to improve the performance. The results show that pressure on the runner blade in Stage 1 and velocity at nozzle outlet have close relation to the turbine performance.

• 한국유통학회지:유통연구
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• 제7권2호
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• pp.21-44
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• 2003

The entry of large discount stores into small cities such as Choonchun or Wonju have had a profound impacts on the businesses of small-sized retailers. The impacts of the entry by large discount store will be much larger than those of the entry by department store or other small-scale retailers. Most of research studies on the competitive retail structure focused on the change of retailing in the advanced countries dynamically and investigated macro-trends in sales and market share. As a result, they tend to overlook the micro aspects of consumers" perception and actual behaviors. Furthermore, they tend to limit their research scopes to relatively competitive retailers not to overall competitive structures. In this study, we analyze the overall competitive structures by investigating the retailers" characteristics, perceptions of consumers on retailers and actual purchase of products across different types of retailers We could obtain competitive retail structure. Based on that, we discuss the strategies on the revitalization and enhancement of small-sized retailers" productivities.

• Applied Microscopy
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• 제22권1호
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• pp.15-32
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• 1992

This study was an attempt to investigate and compare the fine structure of small cells in the space of Disse of various animal livers. All animal livers contained small cells with or without lipid droplets and the one with lipid droplet seemed to be more developed and show an abundance of activity in function. The fine structure of the small cells observed in the nonmammals was similar to that of Ito cell in the mammal. The electron density of the small cells was similar to that of other cell types in the same animal liver. The cisternal dilation of rough endoplasmic reticulum and Golgi apparatus was more predominant in the mammalian Ito cells. In the nonmammalian, aquatic vertebrates, however, lysosomes and filaments are much more abundant in the Ito cell and its abundant cytoplasmic processes rich in filaments were usually extended between the parenchymal cells. The disparity in size of organelles and numbers of lipid droplets in the small cells showed a tendency similar to those of other cell types in the same animal. From these results, it is considered that the small cells in the space of Disse is a Ito cell and the Ito cell without lipid droplets differentiates into the one containing lipid droplets according to the characteristics of the different animals respectively, and that the Ito cells in the mammals are more active in metabolic function, while those in the nonmammalian aquatic vertebrates are abundant in support of parenchyme.

• Journal of Mechanical Science and Technology
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• 제18권9호
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• pp.1604-1613
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• 2004

This paper presents an effective and reliable evaluation method for fracture strength and material degradation of the micro-structure of high temperature service steel weldment using advanced small punch (ASP) test developed from conventional small punch (CSP) test. For the purpose of the ASP test, a lower die with a minimized ${\Phi}$1.5 mm diameter loading ball and an optimized deformation guide hole of ${\Phi}$3 mm diameter were designed. The behaviors of fracture energy (E$\_$sp/), ductile-brittle transition temperature (DBTT) and material degradation from the ASP test showed a definite dependency on the micro-structure of weldment. Results obtained from ASP test were compared and reviewed with results from CSP test, Charpy impact test, and hardness test. The utility and reliability of the proposed ASP test were verified by investigating fracture strength, behavior of DBTT, and fracture location of each micro-structure of steel weldment for test specimen in ASP test. It was observed that the fracture toughness in the micro-structure of FL＋CGHAZ and ICHAZ decreased remarkably with increasing aging time. From studies of all micro-structures, it was observed that FGHAZ microstructure has the most excellent fracture toughness, and it showed absence of material degradation.

• Bulletin of the Korean Chemical Society
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• 제35권11호
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• pp.3267-3274
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• 2014

In order to investigate the effects of the double replacement of $\small{L}$-Pro, $\small{D}$-Pro, $\small{D}$-Leu or Nleu (the peptoid residue for Leu) in the hydrophobic face (positions 9 and 13) of amphipathic ${\alpha}$-helical non-cell-selective antimicrobial peptide $L_8K_9W_1$ on the structure, cell selectivity and mechanism of action, we synthesized a series of $L_8K_9W_1$ analogs with double replacement of $\small{L}$-Pro, $\small{D}$-Pro, $\small{D}$-Leu or Nleu in the hydrophobic face of $L_8K_9W_1$. In this study, we have confirmed that the double replacement of $\small{L}$-Pro, $\small{D}$-Pro, or Nleu in the hydrophobic face of $L_8K_9W_1$ let to a great increase in the selectivity toward bacterial cells and a complete destruction of ${\alpha}$-helical structure. Interestingly, $L_8K_9W_1$-$\small{L}$-Pro, $L_8K_9W_1$-$\small{D}$-Pro and $L_8K_9W_1$-Nleu preferentially interacted with negatively charged phospholipids, but unlike $L_8K_9W_1$ and $L_8K_9W_1$-$\small{D}$-Leu, they did not disrupt the integrity of lipid bilayers and depolarize the bacterial cytoplasmic membrane. These results suggested that the mode of action of $L_8K_9W_1$-$\small{L}$-Pro, $L_8K_9W_1$-$\small{D}$-Pro and $L_8K_9W_1$-Nleu involves the intracellular target other than the bacterial membrane. In particular, $L_8K_9W_1$-$\small{L}$-Pro, $L_8K_9W_1$-$\small{D}$-Pro and $L_8K_9W_1$-Nleu had powerful antimicrobial activity (MIC range, 1 to $4{\mu}M$) against methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant Pseudomonas aeruginosa (MDRPA). Taken together, our results suggested that $L_8K_9W_1$-$\small{L}$-Pro, $L_8K_9W_1$-$\small{D}$-Pro and $L_8K_9W_1$-Nleu with great cell selectivity may be promising candidates for novel therapeutic agents, complementing conventional antibiotic therapies to combat pathogenic microorganisms.