• Journal of Mechanical Science and Technology
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• 제17권3호
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• pp.449-456
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• 2003

In this study, numerical and experimental analysis on the spray atomization characteristics of a GDI injector is performed. For numerical approach, four hybrid models that are composed of primary and secondary breakup model are considered. Concerning the primary breakup, a conical sheet disintegration model and LISA model are used. The secondary breakup models are made based on the DDB model and RT model. The global spray behavior is also visualized by the shadowgraph technique and local Sauter mean diameter and axial mean velocity are measured by using phase Doppler particle analyzer Based on the comparison of numerical and experimental results, it is shown that good agreement is obtained in terms of spray developing process and spray tip penetration at the all hybrid models. However, the hybrid breakup models show different prediction of accuracy in the cases of local SMD and the spatial distribution of breakup.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.3467-3472
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• 2007

The effects of the wall geometry on the spray-wall impingement process of a hollow-cone fuel spray emerging from a high-pressure swirl injector of the Gasoline Direct Injection (GDI) engine were investigated by means of a numerical method. The ized Instability Sheet Atomization (LISA) & Aerodynamically Progressed Taylor Analogy Breakup (APTAB) model for spray atomization process and the Gosman model were applied to model the atomization and wall impingement process of the spray. The calculation results of spray characteristics, such as a spray development process and a radial distance after wall impingement, compared with the experimental ones by the Laser Induced Exciplex Fluorescence (LIEF) technique. It was found that the radial distance of the cavity angle of 90$^{circ]$ after wall impingement was the shortest and the ring shaped vortex was generated near the wall after spray-wall impingement process.

• 천문학회보
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• 제40권1호
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• pp.58.1-58.1
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• 2015

Gravitational-wave has been predicted by Einstein's general relativity in 1916, but its direct detection has failed to date despite of the persistent efforts in the last fifty years in the ground-based gravitational wave detectors. In the centennial year of the birth of general relativity, 'advanced LIGO', one of the most promising Earth-based gravitational wave detectors, plans to start commissioning for the successful discovery of gravitational waves. In addition, a pathfinder satellite of eLISA project, a space-based GW antenna by European Space Agency (ESA), will be launched in the mid of this year. In this talk, we review the current status of gravitational waves detection experiments and discuss its scientific impacts and the possibility of opening the new age of astronomy.

• Child Studies in Asia-Pacific Contexts
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• 제1권1호
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• pp.1-23
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• 2011

Many immigrant youth and their families undergo painful separations and complicated reunification experiences. Using data from the Longitudinal Immigrant Student Adaptation (LISA) study, a 5-year longitudinal, mixed-methods study of newcomer youth to the U.S., we examine the impact of lengthy family separations on youth's mental health and their perceived family conflict. Quantitative analyses demonstrate that longer separations positively predict higher psychological symptoms and family conflict, particularly for girls over a sustained period of time. Qualitative analyses of parent and child responses provide insights into the family reunification experiences.

• Journal of the Korean Wood Science and Technology
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• 제24권4호
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• pp.64-73
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• 1996

고인성 종이의 탄성-소성 파괴를 파괴역학을 이용하여 분석하였다. 탄성-소성 물질의 파괴에 있어서 균열이 언제 진행되기 시작하는지 이론적 판단 기준을 유도하고, mode I 파괴를 linear image strain analysis(LISA)로 관찰한 후, 파괴역학 변수들을 계산하였다. 크랙(crack)이 있는 물질에 외부하중이 작용할 때 변형율 에너지 발산 속도(strain energy release rate)가 그 물질이 견딜 수 있는 파괴저항(fracture resistance)에 도달하면 안정적인 파괴가 진행된다. 이를 이용하여 크랙의 초기 진행시 결점주위의 응력, 파괴저항, 크랙 진행거리, 기하인자(geometry factor) 등을 구하였다. 이 변수들은 종이의 파괴역학적 특성을 정량적으로 나타내므로 유용하게 활용될 수 있을 것이다.

• BMB Reports
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• 제39권4호
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• pp.457-463
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• 2006

Insulin resistance is commonly observed in patients prior to the development of type 2 diabetes and may predict the onset of the disease. We tested the hypothesis that impairment in insulin stimulated glucose-disposal in insulin resistant patients would be reflected in the gene expression profile of skeletal muscle. We performed gene expression profiling on skeletal muscle of insulin resistant and insulin sensitive subjects using microarrays. Microarray analysis of 19,000 genes in skeletal muscle did not display a significant difference between insulin resistant and insulin sensitive muscle. This was confirmed with real-time PCR. Our results suggest that insulin resistance is not reflected by changes in the gene expression profile in skeletal muscle.

• 한국식생활문화학회지
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• 제17권2호
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• pp.97-102
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• 2002

본 연구는 한국에 거주하는 미국인 및 캐나다인의 식품구입 및 한국식당 이용실태를 조사한 결과 한국마켓에서의 식재료가 안전한지를 묻는 질문에 38%가 아니라고 응답하였고 77%가 음용수의 안전성을 확신한다고 대답하였으나 54%의 응답자는 수입된 물을 구입해서 마신다고 하였으며 한국음식을 상당히 좋아하고 한국음식점을 즐겨 찾는 것으로 나타났으며 한국음식의 단맛, 짠맛, spicy한 정도는 강하지 않다고 응답하였고 식당 종업원들의 위생관념에는 만족하지 않는 것으로 나타났다. 대부분의 응답자가 한국마켓에서의 식재료의 안전도에 관해서는 신뢰하고 있었으나, 일부 응답자들은 본국에서 음용수 및 음식을 가져다 먹는다고 응답한 것으로 보아 식재료에 대한 더욱 철저한 위생관리가 필요하다고 여겨지며, 또한 한국음식점 이용에 대한 질문에서도 전반적으로 좋은 반응을 보였으나 종업원의 위생관념의 부족을 지적한 바, 음식점에서의 위생분야에 더욱 주의를 기울여야 할 것을 지적하고자 한다.

• Child Studies in Asia-Pacific Contexts
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• 제4권1호
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• pp.1-12
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• 2014

Emotion is a central feature of social interactions. In this study, we examined age-related changes in emotion expressiveness and emotion knowledge and how young children's emotion expressiveness and knowledge were related. A total of 300 children attending a daycare center contributed data for the study. Observation and interview data relevant to measures of emotion expressiveness and knowledge were collected and analyzed. Both emotion knowledge and expressed positive affect increased with age. Older preschool children expressed positive affect more frequently than did younger preschoolers. Older preschool children also labeled, recognized, and provided plausible causes mores accurately than did younger preschool children. In addition, we tested whether children's errors on the free labeling component conform to the structural model previously suggested by Bullock and Russell (1986) and found that preschool children were using systematic strategies for labeling emotion states. Relations between emotion expressiveness and emotion knowledge generally were not significant, suggesting that emotional competence is only gradually constructed by the child over the preschool years.

• International Journal of Costume and Fashion
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• 제15권2호
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• pp.79-91
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• 2015

Creativity is an ever-increasing research area related to fashion design, namely the documentation and dissemination of creative scholarship. The purpose of this project is to apply creative bridge or creative leap theory to the development of an existing designer's garment collection using the creative design process of an architect. A single case study design was used to investigate the phenomenon of design process creative leap using a direct observation. Results indicate the difficult challenge of producing new and individualized silhouettes for the marketability of clothing, it is apparent that new methods of fostering creativity in designers through non-traditional approaches would benefit the education of apparel designers. Through targeted design practice, educators and practitioners can apply the principles of scientific inquiry into design processes to solve a problem, address a challenge, or create based on personal inspirations.

• 대한기계학회논문집B
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• 제28권5호
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• pp.545-552
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• 2004

The purpose of this study is to improve the prediction ability of the atomization and vaporization processes of GDI spray. Several models have been introduced and compared. The atomization process was modeled using hybrid breakup model that is composed of Linearized Instability Sheet Atomization (LISA) model and Aerodynamically Progressed TAB (APTAB) model. The vaporization process was modeled using Spalding model and Abramzon ＆ Sirignano model. Exciplex fluorescence method was used for comparing calculated with experimental results. The experiment and computation were performed at the ambient pressure of 0.1 MPa, 0.5 MPa and 1.0 MPa and the ambient temperature of 293k and 473k. Comparison of calculated and experimental spray characteristics was carried out and the calculated results of GDI spray showed good agreement with experimental results.