• BMB Reports
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• 제51권9호
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• pp.450-455
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• 2018

Tamoxifen (TAM) is commonly used to treat estrogen receptor (ER)-positive breast cancer. Despite the remarkable benefits, resistance to TAM presents a serious therapeutic challenge. Since several HOX transcription factors have been proposed as strong candidates in the development of resistance to TAM therapy in breast cancer, we generated an in vitro model of acquired TAM resistance using ER-positive MCF7 breast cancer cells (MCF7-TAMR), and analyzed the expression pattern and epigenetic states of HOX genes. HOXB cluster genes were uniquely up-regulated in MCF7-TAMR cells. Survival analysis of in slico data showed the correlation of high expression of HOXB genes with poor response to TAM in ER-positive breast cancer patients treated with TAM. Gain- and loss-of-function experiments showed that the overexpression of multi HOXB genes in MCF7 renders cancer cells more resistant to TAM, whereas the knockdown restores TAM sensitivity. Furthermore, activation of HOXB genes in MCF7-TAMR was associated with histone modifications, particularly the gain of H3K9ac. These findings imply that the activation of HOXB genes mediate the development of TAM resistance, and represent a target for development of new strategies to prevent or reverse TAM resistance.

• Journal of Life Science
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• 제11권1호
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• pp.22-26
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• 2001

In estrogen-dependent MCF-7 human breast cancer cells, $E_2$ at 10 nM stimulated cell proliferation to over 200% compared to the untreated control. EGF and TGF${\alpha}$, which are known as the autocrine/paracrine growth factors induced by $E_2$, also directly stimulated the cell growth in almost as the same extent as $E_2$. DFMO which is the specific inhibitor of ODC could inhibit cell growth even at as low as 0.5 mM. In the treatment with 1 mM DFMO for 4 days, the cell growth was inhibited to 38% of the control. HO-TAM at 1 ${\mu}$M could inhibit the proliferation of MCF-7 cells to 19% of the control. Those inhibitory effects were also found in the cells stimulated with $E_2$, EGF, and TGF${\alpha}$. The inhibitory effects were found even in 2 days of treatment. However, $E_2$, EGF, and TGF${\alpha}$ did not give any effect in the protein synthesis. Neither DFMO or HO-TAM gave any effect on the total protein synthesis. But the pattern of protein secretion was noticeably influenced by the growth stimulants or inhibitors. Proteins of 160, 52, 42, 36, and 32 kDa belonged to the major secretory proteins. Especially, 42 and 36 kDa proteins were most significantly influenced by the treatment of $E_2$, EGF, or TGF$\alpha$. DFMO and HO-TAM inhibited the secretion of these major proteins.

• Asia pacific journal of information systems
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• 제14권1호
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• pp.165-184
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• 2004

This paper focused on developing and empirically testing an EAM(Electronic-Store Acceptance Model), By basing upon Davis' TAM(Technology Acceptance Model) and reflecting the characteristics of EC(Electronic Commerce), the EAM was proposed. This EAM could be regarded as a revised and extended TAM in the EC area. The theoretical rationale of this model was as following: 1) Though Davis' TAM was proposed a powerful tool to explain and predict usage of Information Technology, nowadays, TAM variables(perceived usefulness and ease of use) are posited as key drivers of e-commerce acceptance. 2) In the e-commerce and e-business studies, trust has been emerging as a potentially important antecedent of IT adoption. A famous internet book store was chosen to empirically test the EAM. In order to evaluate reliability and validity of instrument, and validate the research model, SEM(Structured equation model) analysis was conducted. The results showed that perceived usefulness and trust significantly influenced e-Store Acceptance but perceived ease of use did not have significant influence on e-Store Acceptance.

• 한국지능시스템학회논문지
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• 제17권4호
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• pp.526-533
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• 2007

본 논문에서는 조직구성원을 대상으로 하여 이고그램, 인생태도, 스트로크, 시간의 구조화 4개의 이론을 이용한 직무만족의 패턴에 대한 연구를 하였다. 패턴분석의 도구로서는 특별히 패턴분석에 효과적인 모델인 퍼지 TAM 네트워크를 사용하였다. 퍼지 TAM 네트워크의 입력데이터는 교류분석의 4개 이론의 값이며, 출력데이터는 직무만족의 점수를 2개로 나눈 클래스이다. 연구의 결과로서는 4개의 교류분석의 이론과 직무만족의 패턴분석에 대한 트레이닝 데이터의 정답률은 85-100%, 체킹데이터의 정답률은 60%이었다.

• 대한전자공학회논문지SD
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• 제43권10호
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• pp.140-150
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• 2006

본 논문은 SOC 내부의 다양한 코어들을 효율적으로 테스트하기 위한 하드웨어 구조에 초점을 두고 있다. 기존의 한 번에 한 개의 코어만을 순차적으로 테스트하는 방식은 많은 테스트 시간을 요구한다. 이를 보완하고자 본 논문에서는 병렬적으로 여러 코어를 테스트할 수 있는 S-TAM 구조 및 컨트롤러를 제안한다. S-TAM 구조는 테스트 버스 공유 방식을 이용하여 브로드캐스트 방법을 지원하며 이를 기반으로 하여 임의의 코어만을 선택적으로 테스트할 수도 있다. 이뿐 아니라 S-TAM 컨트롤러는 IEEE 1149.1 및 IEEE 1500 등과 같은 서로 상이한 테스트 기반을 통해 구현된 다양한 코어들을 동시에 제어함으로써 효과적인 SOC 테스트를 가능하게 한다.

• Asia pacific journal of information systems
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• 제16권2호
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• pp.159-181
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• 2006

The purpose of this research is to identify the factors affecting user acceptance of mobile banking. To test the hypotheses, this research incorporates trust to extend the model. This study investigates the causal relationship among four factors; perceived ease of use, perceived usefulness, trust, and intention to use in mobile banking. This study also identifies the elements by which these factors are influenced. The result finds that facilitation condition and self-efficacy are significant elements affecting perceived ease of use. System quality, perceived ease of use and trust are significant elements affecting perceived usefulness, However, social influence is found to be not significant. System quality and perceived ease of use are significant elements affecting trust. Conclusively, perceived ease of use, perceived usefulness and trust are significant factors affecting the user acceptance in Mobile banking.

• 경영과학
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• 제26권2호
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• pp.71-89
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• 2009

The purpose of this research is to identify the factors affecting user acceptance of e-learning site. To more precisely explain an individual's behavior of accepting e-learning site, Perceived Interactivity is divided into four components; User Control, Responsiveness, Personalization and Connectedness. This research investigates the causal relationship among four components and basic factors of TAM. This research uses structural equation modeling (SEM) to confirm the validity and analyzes the causal relationship of the suggested model. The results indicates strong support for the validity of proposed model with 54.8% of the variance in behavioral intention to e-learning site. The result finds that all the basic casuality of TAM are significant and most components of Perceived Interactivity are significant. However the path Connectedness to Perceived Ease of Use and User Control to Perceived Playfulness is not significant. Among components of Perceived Interactivity, Personalization is the strongest antecedent of TAM. Perceived Usefulness is the strongest antecedent of behavioral intention of e-learning site.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.1236-1238
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• 2003

The Earth's total magnetic field was extracted from on board TAM (Three Axis Magnetometer) observations of KOMPSAT-1 satellite between June 19th and 21st, 2000. In the pre-processing, the TAM's telemetry data were transformed from ECI (Earth Centered Inertial frame) to ECEF (Earth Centered Earth Fixed frame) and then to spherical coordination, and self-induced magnetic field by satellite bus itself were removed by using an on-orbit magnetometer data correction method. The 2-D wavenumber correlation filtering and quadrant-swapping method were applied to the pre-processed data in order to eliminate dynamic components and track-line noise, respectively. Then, the spherical harmonic coefficients are calculated from KOMPSAT-1 data. To test the validity of the TAM's geomagnetic field, Danish/NASA/French ${\phi}$rsted satellite's magnetic model and IGRF2000 model were used for statistical comparison. The correlation coefficient between ${\phi}$rsted and TAM is 0.97 and IGRF and TAM is 0.96. It was found that the data from on board magnetometer observations for attitude control of Earth-observing satellites can be used to determinate the Earth's total magnetic field and that they can be efficiently used to upgrade the global geomagnetic field coefficients, such as IGRF by providing new information at various altitudes with better temporal and spatial coverage.

• 디지털콘텐츠학회 논문지
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• 제19권3호
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• pp.569-577
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• 2018

근거리 무선통신 (NFC)은 전 세계적으로 주목 받고 있는 유용한 기술이다. NFC 모바일 결제는 많은 금융 기관을 포함한 기술 회사에서 개발되었고 특히 대중교통에 많이 적용되고 있다. 본 연구에서 우리는 NFC 결제 시스템을 채택하려는 의도에 영향을 미치는 NFC 시스템에 관련된 주요 요인들을 확인하였다. 이러한 연구 가설을 검증하기 위하여 최근 한국에서 Post China로 많은 관심을 받고 있는 베트남의 경제 중심지인 호치민시에 거주하는 355 명의 응답자를 대상으로 설문을 통하여 자료를 수집하고 Amos를 활용하여 통계적 분석을 실시하였다. 이론적으로는 기술 수용 모델 (TAM)을 사용하였다. 사회적 영향력, 신뢰, 보안, 사용자의 편의성 모두가 매개변수(인지된 유용성 및 사용용이성)를 통하여 NFC결제 방법 사용의도 및 실제 사용에 영향을 미치는 중요한 역할을 하는 것으로 나타났다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.242-242
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• 2002

The Earth's magnetic field acquired from KOMPSAT-1's TAM (Three-Axis Magnetometer) between June 19th and 21st 2000 was analyzed. The TAM, one of the KOMPSAT-1's Attitude and Orbit Control Subsystems, plays an important role in determining and controlling the satellite's attitude. This also can provide new insight on the Earth's magnetic field. By transforming the satellite coordinate from ECI to ECEF, spherical coordinate of total magnetic field was achieved. These data were grouped into dusk (ascending) and dawn (descending) data sets, based on their local magnetic times. This partitioning is essential for performing 1-D WCA (Wavenumber Correlation Analysis). Also, this enhances the perception of external fields in the Kompsat-1's TAM magnetic maps that were compiled according to different local. The dusk and dawn data are processed independently and then merged to produce a total field magnetic anomaly map. To extract static and dynamic components, the 1-D and 2-D WCAs were applied to the sub-parallel neighboring tracks and dawn-dusk data sets. The static components were compared with the IGRF, the global spherical harmonic magnetic field model. The static and dynamic components were analyzed in terms of corefield, external, and crustal signals based on their origins.