• Journal of Life Science
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• v.21 no.1
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• pp.127-133
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• 2011

${\beta}$-Galactosidase was immobilized on chitosan bead by covalent bonding using glutaraldehyde. The characteristics of the immobilized enzyme were investigated. Maximum immobilization yield of 75% was obtained on chitosan bead. Optimum pH and temperature for the immobilized enzyme was 7.0 and $50^{\circ}C$, respectively. The immobilized enzyme showed a broader range of pH and temperature compared to a free one. A mathematical model for the operation of the immobilized enzyme in a packed-bed reactor was established and solved numerically. Under different inlet lactose concentrations and feed flow rate conditions, lactose conversion was measured in a packed-bed reactor. The experimental results of continuous operation in a packed-bed reactor were compared to theoretic results using Michaelis-Menten kinetics with competitive product inhibition and external mass transfer resistance. The model predicted the experimental data with errors less than 5%. Process optimization of continuous operation in a packed-bed reactor was also conducted. In a recirculation packed-bed operation, conversion of lactose was 97% in 3 hours. In a continuous packed-bed operation, the effect of flow rate and initial lactose concentration was investigated. Increasing flow rates and initial lactose concentration decreased the conversion of substrate.

• Journal of the Economic Geographical Society of Korea
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• v.10 no.3
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• pp.344-353
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• 2007

Business incubators (BIs) could be regarded as an effective mechanism for linking research and industry to inspire technology and knowledge based entrepreneurship and innovation of start-up SMEs. The performance of BIs for small and medium enterprises (SMEs) innovation should be differentiated in accordance with the technology capacity of SMEs, the national entrepreneurial culture and characters in each economy. Therefore, the research intended to categorize BIs in the selected 10 APEC member economies into four types by investigating the issue of member economies' strategies, functions and characteristics in various focused programs.

• Journal of the Korea Fashion and Costume Design Association
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• v.8 no.1
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• pp.145-154
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• 2006

본 연구는 미국 쇼핑몰 내에서의 소비자행동에 관한 것으로, 인구통계학적 변수와 소핑가치 및 쇼핑의도와의 관계를 모델검증을 통하여 밝혔다. 우선 쇼핑가치와 쇼핑의도 하위차원의 구조를 살펴보면, 소비자가 인지한 쇼핑가치를 쾌락적 쇼핑가치와 실용적 쇼핑 가치로 구분하였다. 또한 기존연구와는 달리 쇼핑의도 변수에 있어서는 다차원적인 구조의 접근을 시도하여 쇼핑의도의 차원을 경제적, 외식, 기분전환, 서비스 이용 의도로 분류한 모델을 제시하였다. 인구통계학적 변수는 소비자가 인지한 쇼핑가치에 영향을 미치고 쇼핑가치는 소비자의 쇼핑의도에 영향을 미치는 인과적인 모델을 검증해본 결과를 살펴보면, 다음과 같다. 제시된 쇼핑가치 및 쇼핑의도의 차원은 통계적으로 유의하였으며, 인종 및 성별의 인구통계학적 변수는 쇼핑가치에 영향을 미치고 쇼핑가치는 쇼핑의도에 영향을 미치는 모델의 구조 또한 유의한 것으로 나타났다. 실용적 쇼핑 가치의 인지에 있어서 백인과 흑인간의 차이는 없었으나, 쾌락적 쇼핑 가치에서는 차이를 보여 흑인이 백인보다 쾌락적 쇼핑가치를 더욱 느낀 것으로 나타났다. 성별의 차이에서는 쾌락적 쇼핑가치뿐 아니라 실용적 쇼핑가치에서도 여성이 남성보다 더 큰 반응을 보였다. 또한 쾌락적 및 실용적 쇼핑가치 모두 쇼핑의도의 전체 차원들과 정적인 관계가 있는 결과를 보여, 실용적 쾌락적 쇼핑가치를 더욱 인지하면 할수록 경제적, 외식, 기분전환, 서비스 이용의 쇼핑의도 모두 높은 것으로 나타났다.

• Journal of Korean Academy of Nursing
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• v.34 no.3
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• pp.515-524
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• 2004

Purpose: The purpose of this study was to develop and test a model to explain the transition state for Korean middle-aged women focusing on the transition concept. Method: A hypothetical model was constructed based on the transition model of Schumacher & Meleis(1994) and tested. Thehypothetical model consisted of 5 latent variables and 11 observed variables. Exogenous variables were demographic characteristics, obstetric characteristics, and health behavior. Endogenous variables were transition state and quality of life with 6 paths. The data from 221 middle-aged women selected by convenience was analyzed using covariance structure analysis. Result: The final model which was modified from the hypotheticalmodel improved to GFI=0.97, AGFI=0.94, NFI=0.94, and NNFI=0.95. The transition state was influenced directly by demographic characteristics, quality of life, and also indirectly by health behaviors. However, the influence of obstetric characteristics was not significant. The transition state was accountable for 68% of the variance by these factors. Conclusion: These results suggest that enhancing health behaviors of the women are necessary to increase quality of life and it consequently contributes toimproving the transition state. This model could be used to explain the health related vulnerability in these ages and to diagnosis individual women.

• 한국벤처창업학회:학술대회논문집
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• 2021.04a
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• pp.27-32
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• 2021

최근 산업계 전반은 코로나19 장기화에 따라 빠른 속도로 디지털트랜스포메이션이 가속화 되고 있다. 디지털트랜스포메이션의 비즈니스 모델은 기업의 성과에 영향을 미치는데, 새로운 비즈니스 모델로서의 가능성은 기업의 성과와 결과에 영향을 미친다. 또한 산업생태계 자체가 디지털 기술로 인해 재구성되는 디지털 변혁 시대 스타트업의 하이퍼스케일업(Hyper-Scaleup)이 중요해지고 있다. 코로나 대유행시기 동안 사회적 거리두기 정책으로 인해 스타트업은 많은 손실을 경험하였고, 이러한 문제를 극복하기 위해 비즈니스 피벗이 필요하며 비즈니스 전환은 필수이다. 물리적 제한이 없는 디지털 세계에서 변화하는 고객의 변화에 신속하게 대응해야 하고 이러한 변화 대응력을 높여야 하는 벤처 생태계를 중심으로 피벗이 중요한 비즈니스 전략으로 등장하고 있다. 이에 따라 본 연구에서는 첫째, 스타트업의 새로운 가치창출을 위해 창업아이템, 하이퍼스케일업, 비즈니스 피벗의 개념을 분석하였다. 둘째, 창업생태계의 디지털 전환 시점에서 창업아이템과 하이퍼스케일업이 창업성과와의 실증 분석을 통해 유의한 영향 관계를 규명하였다. 셋째, 창업아이템과 하이퍼스케일업이 창업성과에 영향을 미칠 때 비즈니스 피벗의 조절효과를 분석하였다. 마지막으로 이러한 연구결과를 바탕으로 스타트업 관점에서 디지털트랜스포메이션을 바르게 이해하고, 실무적 시사점을 제시하였다.

• Journal of Korea Society of Industrial Information Systems
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• v.14 no.1
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• pp.73-89
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• 2009

This research examines the factors that influence a consumer's decision to switch to new self-service technologies. The model related to attitudes, anticipated outcomes and intentions to change a behavior was assessed using structural equation modeling at the context of a banking industry. The results revealed that 1) an attitude toward a staff, Internet banking, and an ATM would influence an attitude toward a bank, 2) an attitude toward Internet banking and ATM influence utility and enjoyment, and an attitude toward Internet banking and staff affect social acceptance, 3) an attitude toward a bank was positively associated with enjoyment, 4) an attitude toward Internet banking had a positive effect on the intention, but an attitude toward an ATM had a negative one, and 5) both anticipated outcomes, enjoyment and social acceptance, were found to influence an intention to change behavior, but utility was found to affect negatively.

• Journal of Korea Port Economic Association
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• v.39 no.1
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• pp.17-34
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• 2023

The maritime industry is undergoing significant changes due to digitalization and decarbonization, collectively known as "2D." This study investigates how these transformations are impacting the industry's business models. Since the changes are still ongoing, a cognitive approach was used to derive business models, rather than relying on actual case studies. The study presents experimental maritime business models that correspond to the four types of business model frameworks (or archetypes), along with recent trends for each model. The research results show that new business models are emerging in various areas, including the commercial and technical fields of the maritime industry. This thought-provoking study is significant as a pioneering investigation that will stimulate subsequent case-based research in academia and provide strategic guidance to market participants or policy makers in the maritime industry.

• Journal of the Korean Geotechnical Society
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• v.22 no.4
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• pp.61-71
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• 2006

A numerical procedure is presented fur evaluating seismic liquefaction on sloping ground sites. The procedure uses a fully coupled dynamic effective stress analysis with a plastic constitutive model called UBCSAND. The model was first calibrated against laboratory element behavior. This involved cyclic simple shear tests performed on loose sand with and without initial static shear stress. The numerical procedure is then verified by predicting a centrifuge test with a slope performed on loose Fraser River sand. The predicted excess pore pressures, accelerations and displacements are compared with the measurements. The results are shown to be in good agreement. The shear stress reversal patterns depend on static and cyclic shear stress levels and are shown to play a key role in evaluating liquefaction response in sloping ground sites. The sand near the slope has low effective confining stress and dilates more. When no stress reversals occur, the sand behaves in a stiffer manner that curtails the accumulated downslope displacements. The numerical procedure using UBCSAND can serve as a guide for design of new soil structures or retrofit of existing ones.

• Journal of Korean Library and Information Science Society
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• v.55 no.2
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• pp.267-291
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• 2024

Since the introduction of the OA transformative agreement as a new way of licensing electronic resources, the number of OA transformative agreements has continued to grow. Despite the wide range of content that should be included in the agreement due to the nature of the OA transformative agreement, there is a lack of research on OA transformative agreements. As a basis for developing a standard for OA transformative agreements, this study examines the current status of OA transformative agreements and analyzes the differences between two types of OA transformative agreements and the subscription contract. It was found that the number of OA transformative agreements has increased significantly worldwide, but the disclosure of OA transformative agreements has not been universalized. The overall structure of two different types of OA transformative agreements and a subscription contract is similar, but there are differences in the detailed clauses. In the OA transformative agreement, the detailed clauses related to the characteristic of the transformative agreement were newly created, or the details of the transformative agreement were added to the existing clauses of the subscription agreement. There were also some differences between the two types of agreements, identifying clauses that differed in content regardless of the OA transformative agreement. The study concluded that it is important to standardize the OA transformative agreement, as the number of different clauses between agreement types may increase the burden on librarians. This study is significant in that it provides a basis for the development of standardized agreements by examining the overall status of OA transformative agreements and analyzing actual agreements.

• Korean Journal of Plant Tissue Culture
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• v.25 no.5
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• pp.323-327
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• 1998

The flavonoid biosynthetic pathway has been studied as a genetic model system, particularly in Petunia hybrida. In order to study the flavonoid biosynthetic pathway, we constructed a fusion gene system between Cauliflower Mosaic Virus (CaMV) 35S promoter and eggplant flavonoid 3', 5'-hydroxylase in pBI 121 plasmid. An optimal condition for plant regeneration was observed when internode explants were cultured on MS medium supplemented with IAA 0.2 mg/L plus BA 3 mg/L. For plant transformation internode explants of Petunia hybrida were precultured on BM medium supplemented with IAA 0.2 mg/L plus BA 3 mg/L. Putative transgenic plants were selected on medium containing kanamycin 50 mg/L plus cefotaxim 300 mg/L. Putative selected transformants were confirmed by amplification of selectable marker gene (nptII) by polymerase chain reaction (PCR) and Southern hybridization of flavonoid 3',5'-hydroxylase gene.