• Biomolecules & Therapeutics
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• 제4권1호
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• pp.103-109
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• 1996

To investigate the effect of the third intracellular loop (i3 loop) peptide of human $\beta$$_2$-adrenergic receptor on receptor agonist binding, we expressed third intracellular loop region of human $\beta$$_2$-adrenergic receptor as glutathione S-transferase fusion protein in E. coli. DNA fragment of the receptor gene which encodes amino acid 221-274 of human $\beta$$_2$-adrenergic receptor was amplified by polymerase chain reaction and subcloned into the bacterial fusion protein expression vector pGEX-CS and expressed as a form of glutathione-S-transferase (GST) fusion protein in E. coli DH5$\alpha$. The receptor fusion protein was identified by SDS-PAGE and Western blot using monoclonal anti-GST antibody. The fusion protein expressed in this study was purified to an apparent homogeneity by glutathione Sepharose CL-4B affinity chromatography. The purified i3 loop fusion proteins at a concentration of 10 $\mu\textrm{g}$/ι caused right shift of the isoproterenol competition curve of [$^3$H]Dihydroalprenolol binding to hamster lung $\beta$$_2$-adrenergic receptor indicating lowered affinity of isoproterenol to $\beta$$_2$-adrenergic receptor possibly due to the uncoupling of receptor and G protein in the presence of the fusion protein. The uncoupling of receptor and G protein suggests that i3 loop region plays a critical role on $\beta$$_2$-adrenergic receptor G protein coupling.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제6권2호
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• pp.225-233
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• 2000

번호 이동성은 사용자가 전화 번호의 변경 없이 통신 사업자, 지역, 서비스 종류를 바꿀 수 있는 능력을 제공하는 지능망 서비스이다. 번호 이동성은 통신 시장의 경쟁을 활성화 시키기 위해 반드시 필요한 서비스로, 최근 많은 나라에서 통신 사업자간에 규율을 정하고 번호 이동성 서비스를 도입하기 위한 작업을 추진 중에 있다. 번호 이동성 서비스를 제공하기 위해서는 통신 사업자들이 모든 고객의 정보를 각각 관리해야 하므로, 공통된 고객 정보를 관리하기 위한 단일화된 방법이 필요하다. 이러한 기능을 담당하는 것이 NPAC이다. 한편, 최근 CORBA는 분산 시스템 관리를 위한 주요 기술로 대두되고 있으며, CORBA를 지능망에 적용하기 위해 지능망, TMN, CORBA의 통합에 관한 연구가 진행되고 있다. 이러한 연구의 일환으로, 본 논문에서는 번호 이동성 서비스 관리에 TMN과 CORBA를 적용하기 위한 연구를 소개한다. 우선 CORBA 기반의 번호 이동성 서비스 관리 구조를 기술하고, CORBA를 이용하여 NPAC을 구현하는 방안에 대해 설명한다.

• BMB Reports
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• 제29권2호
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• pp.175-179
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• 1996

Viral surface proteins are known to play an essential role in attachment of the virus particle to the host cell membrane. In case of the hepatitis B virus (HBV) several reports have described potential receptors on the target cell side, but no definite receptor protein has been isolated yet. As for the viral side, it has been suggested that the preS region of the envelope protein, especially the preS1 region, is involved in binding of HBV to the host cell. In this study, preS1 region was recombinantly expressed in the form of a maltose binding protein (MBP) fusion protein and used to identify and visualize the expression of putative HBV receptor(s) on the host cell. Using laser scanned confocal microscopy and by FACS analysis, MBP-preS1 proteins were shown to bind to the human hepatoma cell line HepG2 in a receptor-ligand specific manner. The binding kinetic of MBP-preS1 to its cellular receptor was shown to be temperature and time dependent. In cells permeabilized with Triton X-100 and treated with the fusion protein, a specific staining of the nuclear membrane could be observed. To determine the precise location of the receptor binding site within the preS1 region, several short overlapping peptides from this region were synthesized and used in a competition assay. In this way the receptor binding epitope in preS1 was revealed to be amino acid residues 27 to 51, which is in agreement with previous reports. These results confirm the significance of the preS1 region in virus attachment in general, and suggest an internalization pathway mediated by direct attachment of the viral particle to the target cell membrane.

• 한국항만경제학회지
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• 제31권3호
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• pp.93-105
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• 2015

본 연구는 최근까지 이루어진 공항의 집중도 및 항공 유동성 자료를 바탕으로 한 선행연구를 고찰하고, 항공 및 공항의 환경변화에 따라 변화되고 있는 아시아 주요공항의 화물 물동량 구조를 파악하였다. 또한, 아시아 지역에서의 화물 전이 현상을 분석하여, 경쟁공항들의 경쟁수준을 파악하여 향후 전략적 시사점을 제시하는 것을 본 연구의 목적으로 하였다. 현재 동북아 권역의 과점화는 꾸준히 약화되고 있으나 이는 중국공항의 성장에 따른 결과이며 이 지역에서의 푸동공항은 지속적인 물동량 확대는 새로운 과점화 증대 현상도 일어날 수 있다는 것을 시사한다. 또한, 2000년부터 2012년까지 항공화물 변이 효과분석 결과에 의하면 인천공항의 항공화물은 약 42만 톤이, 나리타공항은 약 128만 톤이 동북아 권역의 다른 공항으로 전이된 것으로 분석되었다. 이는 일부가 직접경쟁이 가능한 푸동공항으로 전이된 것으로 판단할 수 있어 향후 전이가 지속적으로 창출되는 원인과 이유에 대한 추후 연구도 필요한 것으로 판단된다.

• 한국건축시공학회지
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• 제21권4호
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• pp.319-331
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• 2021

본 연구는 베리-허핀달 지수를 활용한 글로벌 주요 국가의 해외건설 지역별 및 공종별 다각화 및 다변화 지수를 분석하였다. 분석결과, 글로벌 설계 및 시공기업의 해외비중이 높고, 공종별 및 지역별 다각화 정도가 높은 국가들은 유럽 선진 국가들이 대부분을 차지하고 있다. 한국은 시공기업의 공종별 전문화를 통한 다각화를 추진하고 있고, 설계기업은 공종별 및 지역별로 전문화 및 일부 지역에 편중되어 있다. 향후에는 한국의 글로벌 건설기업은 선진국과 같이 해외사업 지역 다변화 및 공종 다각화로 해외경쟁력을 강화할 필요가 있다.

• 산업경영시스템학회지
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• 제23권58호
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• pp.41-47
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• 2000

Global(mega) event has increased throughout the 1990s, with the biggest surge occurring in the Asia-Pacific region. Along with this upward trend, competition for more desirable tourists is also surging, so destinations cannot be complacent (Getz, 1997). Event is appearing as the powerful method in the fierce competition around the industry. International events like 99 Hanam Environment Expo have been held annually in Korea since 1991 in which the local government system started. The main roles of event are to enhance the image of communities and attract tourists (Kotler and Haider and Rein, 1993), to strengthen destination attractiveness as drawing power (Mill and Morrison, 1985), and so on. Focused on the destination image, the research (Sirakaya and Sheppard and McLellan, 1997) about the effect of perceived safety at a potential vacation destination showed that destination marketers, travel agents, and hospitality industry members should be concerned with improving their images when such images are negative with regard to safety. Event industry in Korea does not seriously recognize the importance of the safety management against accidents known for tarnishing the destination images. Moreover few safety standards or studies for event industry can be found. This paper investigated the safety factors considered by visitors of 99 Hanam Environment Expo and analyzed the correlation between the safety factors and the demographic characteristics of the visitors.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2001년도 춘계종합학술대회
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• pp.575-578
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• 2001

전화번호이동성이란 전화서비스 가입자가 전화망 사업자, 지역, 서비스의 종류를 변경하여도 종전에 사용하던 전화번호를 변경하지 않고 그대로 사용할 수 있는 것을 뜻한다. 새로운 통신사업자가 계속 등장함에 따라 국가적으로 이들의 공정한 경쟁을 유도하는 정책이 필요하게 되었으며 전화번호 이동성의 제공은 후발 통신사업자가 선발 통신사업자와 공정한 경쟁을 할 수 있는 토대를 만드는 것으로 인식되면서 국내에서도 전화번호이동성을 제공하기 위한 법률이 만들어지고 전 사업자가 동의할 수 있는 전화번호이동성을 제공하기 위한 표준이 필요하게 되었다. 이를 위하여 번호이동성 구현을 위한 규격을 개발하였으며, 번호이동성 구현을 위한 규격에는 호처리구조, 망구조 요구사항 등이 있으며 본 논문에서는 상기와 같은 규격에 관하여 다룬다.

• BMB Reports
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• 제43권12호
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• pp.807-812
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• 2010

$NF{\kappa}B$ and ZAS3 are transcription factors that control important cellular processes including immunity, cell survival and apoptosis. Although both proteins bind the ${\kappa}B$-motif, they produce opposite physiological consequences; $NF{\kappa}B$ activates transcription, promotes cell growth and is often found to be constitutively expressed in cancer cells, while ZAS3 generally represses transcription, inhibits cell proliferation and is downregulated in some cancers. Here, we show that ZAS3 inhibits $NF{\kappa}B$-dependent transcription by competing with $NF{\kappa}B$ for the ${\kappa}B$-motif. Transient transfection studies show that N-terminal 645 amino acids is sufficient to repress transcription activated by $NF{\kappa}B$, and that the identical region also possesses intrinsic repression activity to inhibit basal transcription from a promoter. Finally, in vitro DNA-protein interaction analysis shows that ZAS3 is able to displace $NF{\kappa}B$ by competing with $NF{\kappa}B$ for the ${\kappa}B$-motif. It is conceivable that ZAS3 has therapeutic potential for controlling aberrant activation of $NF{\kappa}B$ in various diseases.

• 한국항해항만학회지
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• 제46권5호
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• pp.449-457
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• 2022

The Port of Busan is currently ranked as the seventh largest container port worldwide in terms of cargo throughput. However, port competition in the Far-East region is fierce. The growth rate of container throughput handled by the port of Busan has recently slowed down. In this study, we analyzed how economic conditions and multiple external shocks could influence cargo throughput and identified potential implications for port business. The aim of this study was to build a model to accurately forecast port throughput using the ARIMA model, which could incorporate external socio-economic shocks, and the VEC model considering causal variables having long-term effects on transshipment cargo. Findings of this study suggest that there are three main areas affecting container throughput in the port of Busan, namely the Russia-Ukraine war, the increased competition for transshipment cargo of Chinese ports, and the weaker growth rate of the Korean economy. Based on the forecast, in order for the Port of the Port of Busan to continue to grow as a logistics hub in Northeast-Asia, policy intervention is necessary to diversify the demand for transshipment cargo and maximize benefits of planned infrastructural investments.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2023년도 춘계학술대회
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• pp.118-120
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• 2023

Increasing port competition driven by the containerisation has motivated ports and terminals to focus on their performance to efficiently utilise the available resources and to make strategic decisions in port development and expansion. With both inter-port andintra-port competition increasing in the port of Colombo, this study aims to measure the efficiency of the container terminals in Colombo comparing to terminals in the port of Busan using the DEA window analysis to determine their operational efficiency and to provide suggestions for future port development activities. Multiple window analyses were conducted using CCR and BCC models with different orientations and window lengths to compare the efficiencies of 11 DMUs in both ports during the period from 2015-2019 to measure the efficiencies prior to the COVID-19 pandemic. Results revealed the largest terminal operator, PNC in Busan, to be the most efficient overall, while the second highest efficiency was recorded by one of the smallest terminal operators, SAGT in Colombo, among the sample. Although use of DEA in port performance measurement has been popular for many years, efficiency measurements in the port of Colombo, the main hub port in the South Asian region, has not been comprehensively studied so far.