• BMB Reports
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• v.51 no.9
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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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• v.11 no.1
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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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• v.14 no.1
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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.

• Journal of the Korean Institute of Intelligent Systems
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• v.17 no.4
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• pp.526-533
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• 2007

In this paper, we study to the pattern of job satisfaction using four theories of transactional analysis-egogram, life positions, strokes, time structuring-for organizational members. The tool of pattern analysis is used fuzzy TAM network which Is especially effective for pattern analysis. The input data of fuzzy TAM network ate values of four theories in transactional analysis, the output data is the classes which is divided by two groups from score of job satisfaction. From the result of this study, the correct rates of training data and checking data are 85-100% and 60%, respectively.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.10 s.352
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• pp.140-150
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• 2006

In this paper, we present a new hardware architecture for testing various cores embedded in SoC. The conventional solutions need much testing time since only one core is tested at single test period. To enhance this, S-TAM, a novel test architecture, and its controller which enable parallel testing of various cores are proposed. S-TAM supports bus sharing to broadcast testing and cores to be tested are selected by using it. In addition, S-TAM controller enables the effective SoC test by simultaneous controlling the various test cores which are based on the different test architectures like IEEE 1149.1 and IEEE 1500.

• Asia pacific journal of information systems
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• v.16 no.2
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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.

• Korean Management Science Review
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• v.26 no.2
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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.

• Proceedings of the KSRS Conference
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• 2003.11a
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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.

• Journal of Digital Contents Society
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• v.19 no.3
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• pp.569-577
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• 2018

Near-Field Communication(NFC) is a useful technology that is receiving worldwide attention. NFC mobile payment systems are being developed by many technology companies including financial institutions especially for the public transportation. In this research we find several factors for the intention to adopt NFC payment system. We surveyed 355 respondents who live in Ho Chi Minh city, Vietnam which became more interested by Korean as a post China country to test our research hypothesis. Using Technology Acceptance Model(TAM) we find that the factors of Social influence, Trust, Security, and Users' Convenience play the significant role to the factor of Intention to Use of NFC payment system.

• Proceedings of the KSRS Conference
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• 2002.10a
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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.