• 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.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.301-304
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• 1999

밀리미터파 대역의 아날로그 광전송을 위한 진행파형 (travel ing wave, TW) 전계흡수 광변조기 (electroabsorption modulator, EAM)와 광수신기의 설계에 대해 발표하고자 한다. TW EAM 및 TW 광수신기의 일반적인 형태인 ridge-type의 co-planar waveguide (CPW)구조에서의 마이크로파의 전송특성을 3차원 FDTD로 분석하여 광파와 전파의 속도 정합 등을 이루는 최적화 구조를 설계하였다. TW EAM의 경우 광세기 변조의 비선형 응답특성에 있어서 마이크로파 손실과 소자길이가 RF 신호의 혼변조 왜곡 (intermodulation distortion)과 SFDR (spurious free dynamic range)성능에 미치는 영향도 이론적으로 조사하였다. TW PIN 광수신기의 경우 광파와 마이크로파의 속도정합의 영향과 이전에는 고려되지 않았던 photo-generated 전송자의 진성 영역에서의 transit time이 광수신기의 밴드 폭에 미치는 영향을 분석하여 최적화 설계하였다.

• Korean Journal of Veterinary Research
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• v.53 no.4
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• pp.225-230
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• 2013

To better understand the role of macrophages in early stages of experimental autoimmune myocarditis (EAM), we compared the expression of inducible nitric oxide synthase (iNOS) and arginase-1, markers for classically activated M1 and alternatively activated M2 macrophages, respectively, in the hearts of EAM-affected and control rats. Immunohistochemical evidence revealed that both iNOS-positive and arginase 1-positive macrophages were found in EAM lesions, while some cells were co-localized with both markers. This finding suggests that the increased level of arginase-1, which is partly from M2 macrophages, contributes to the modulation of EAM, possibly through the reduction of nitric oxide in the lesion.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.4
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• pp.41-47
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• 2004

In this paper, we analyze the microwave characteristics of traveling-wave electro-absorption modulator (TW-EAM) considering the microwave feedline and the impedance mismatch. The TW-EAM is analyzed by using the equivalent circuit model. The capacitance and the inductance of the equivalent circuit are evaluated by using 3-dimensional finite difference time domain (FDTD) method, while the microwave feedline is analyzed by momentum method. In a viewpoint of microwave characteristics, we present the effect of the structure and the length of microwave feedline.

• The Korean Journal of Physiology and Pharmacology
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• v.23 no.2
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• pp.103-111
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• 2019

The study is to investigate effects of andrographolide on experimental autoimmune myocarditis (EAM). Lewis rats were immunized on day 0 with porcine cardiac myosin to establish EAM. The EAM rats were treated with either andrographolide (25, 50, 100 mg/kg/day) or vehicle for 21 days. An antigen-specific splenocytes proliferation assay was performed by using the cells from control rats immunized with cardiac myosin. Survival rates, myocardial pathology and myocardial functional parameters (left ventricle end-diastolic pressure, ${\pm}dP/dt$ and left ventricular internal dimension) of EAM rats received andrographolide were significantly improved. Andrographolide treatment caused an decrease in the infiltration of $CD3^+$ and $CD14^+$ positive cells in myocardial tissue. Moreover, andrographolide treatment caused a reduction in the plasma levels of tumor necrosis factor-alpha, interleukin-17 (IL-17) and myosin-antibody, and an increase in the level of IL-10 in EAM rats. Oral administration of andrographolide resulted in the decreased expression of p-PI3K, p-Akt without any change of PI3K and Akt. Further results indicate andrographolide significantly inhibited myosin-induced proliferation in splenocytes, and this effect was inhibited by co-treatment of SC79 (Akt activator). Our data indicate andrographolide inhibits development of EAM, and this beneficial effect may be due to powerful anti-inflammatory activity and inhibitory effect on PI3K/Akt pathway.

• Journal of Physiology & Pathology in Korean Medicine
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• v.31 no.2
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• pp.111-117
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• 2017

The anti-cancer effects of Astragalus membranaceus (AM) and Adenophora triphylla var. japonica (AT) have been described. Each of their effects mainly focused on the immunopotentiating and apoptosis inducing-ability in several cancer cell lines. Although the combination of AM and AT is occasionally used in Chinese medicine to treat lung cancers, their synergistic effect has not been proved yet. This study was designed to verify whether AM combined with AT exhibits a synergistic anti-cancer effect in H1299 human lung carcinoma cells. The ethanol extracts of AM (EAM) and AT (EAT) showed only slight cytotoxicity in H1299 cells when treated alone. However, the combination of EAM and EAT markedly suppressed the cell growth measured by MTT assay and trypan blue counting assay. In addition, co-treatment of EAM with EAT significantly reduced the colony-forming ability compared with single treatment of EAM or EAT in H1299 cells. We demonstrated that the synergistic effect of AM and AT was related with apoptosis induction proved by an accumulation of chromatin condensation, annexin V-positive cells, sub-G1 phase population, and cleaved-PARP expression, which were not observed by single treatment of EAM or EAT. In conclusion, the combination of EAM and EAT exhibited superior anti-cancer activity in H1299 cells than single treatment of EAM or EAT. We suggest that EAM combined with EAT might be a novel therapeutic option for lung cancer patients, and provide a reference for the development of more effective combination of Chinese herbs to treat lung cancer.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.05a
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• pp.374-377
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• 2004

In the highly competitive world, there has been a concomitant increase in the need for the research and planning methodology, which can perform an advanced assessment of technological opportunities and an early perception of threats and possibilities of the emerging technology according to the nation's economic and social status. the purpose of this research is to suggest schematized change aspects and new research directions hidden in bibliographical phenomenon of a paper in the science and technology field to science and technology researchers and policy planners. For this, the field this paper researches is the next generation OLED field. Thereason to choose this field is due to the importance of the next generation OLED, and wide scope connected by various fields. Besides, to measure application and technological fields by using bibliographical method and technology is as important as in a basic research field.

• Transactions of the Korean hydrogen and new energy society
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• v.15 no.4
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• pp.257-265
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• 2004

Numerical analysis, as EAM(Embedded Atom Method), in the atomic level is necessary to analyze the relation between the hydrogen and hydrogen absorption metals. EAM established on density functional theory was developed as a new means for calculating various properties and phenomena of realistic metal systems. In this study, we had constructed the EAM program from constitutive formulae and parameters of the hydrogen, nickel and palladium for the purpose of predicting the expansion behavior on hydrogen absorbing. In result, not only the ground state properties of metals but also lattice constants and the volume expansion ratio of metal hydrides show good agreement with Daw's data and experiment data.

• Investigative Magnetic Resonance Imaging
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• v.21 no.3
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• pp.131-138
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• 2017

Purpose: To optimize the timing of scans using cardiac magnetic resonance contrast-enhanced timing robust angiography (CMR-CENTRA) for electroanatomic mapping (EAM) of the right atrium (RA) and left atrium (LA) in patients with atrial fibrillation (AF). Materials and Methods: Fifty patients with AF (38 men; mean age, $59.6{\pm}9.3years$) underwent CMR-CENTRA in preparation for EAM. The CMR-CENTRA data were acquired at five different scan times: 0 seconds, 5 seconds, 10 seconds, 15 seconds, and 20 seconds after an intravenous injection of contrast media. To evaluate the degree of contrast enhancement, right atrial relative contrast (RA-RC) and left atrial relative contrast (LA-RC) on the CMR-CENTRA scans were assessed at each time point. The three-dimensional (3D) reconstruction of the RA and LA for the EAM system was performed using the CMR-CENTRA data. Results: A CMR-CENTRA at a scan time of 10 seconds showed significantly greater LA-RC (P < 0.05) compared with all other scan times. A CMR-CENTRA at a scan time of 15 seconds showed significantly greater RA-RC (P < 0.05) compared with all other scan times. In the 3D reconstruction of the RA, the success rates of CMR-CENTRA at scan times of 10 seconds and 15 seconds were 18% and 100%, respectively. In the 3D reconstruction of the LA, the success rates of CMR-CENTRA at 10- and 15-second scan times were 100%. Conclusion: The CMR-CENTRA data acquired at 15 seconds after the injection of contrast media is appropriate for the preparation of an EAM system that is focused on the RA and LA in patients with AF.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.220-220
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• 2013

Surface-normal transmission electro-absorption modulator (EAM) are attractive for high-definition (HD) three-dimensional (3D) imaging application due to its features such as small system volume and simple epitaxial structure [1,2]. However, EAM in order to be used for HD 3D imaging system requires uniform modulation performance over large area. To achieve highly uniform modulation performance of EAM at the operating wavelength of 850 nm, it is extremely important to remove the GaAs substrate over large area since GaAs material has high absorption coefficient below 870 nm which corresponds to band-edge energy of GaAs (1.424 eV). In this study, we propose and experimentally demonstrate a transmission EAM in which highly selective backside etching methods which include lapping, dry etching and wet etching is carried out to remove the GaAs substrate for achieving highly uniform modulation performance. First, lapping process on GaAs substrate was carried out for different lapping speeds (5 rpm, 7 rpm, 10 rpm) and the thickness was measured over different areas of surface. For a lapping speed of 5 rpm, a highly uniform surface over a large area ($2{\times}1\;mm^2$) was obtained. Second, optimization of inductive coupled plasma-reactive ion etching (ICP-RIE) was carried out to achieve anisotropy and high etch rate. The dry etching carried out using a gas mixture of SiCl4 and Ar, each having a flow rate of 10 sccm and 40 sccm, respectively with an RF power of 50 W, ICP power of 400 W and chamber pressure of 2 mTorr was the optimum etching condition. Last, the rest of GaAs substrate was successfully removed by highly selective backside wet etching with pH adjusted solution of citric acid and hydrogen peroxide. Citric acid/hydrogen peroxide etching solution having a volume ratio of 5:1 was the best etching condition which provides not only high selectivity of 235:1 between GaAs and AlAs but also good etching profile [3]. The fabricated transmission EAM array have an amplitude modulation of more than 50% at the bias voltage of -9 V and maintains high uniformity of >90% over large area ($2{\times}1\;mm^2$). These results show that the fabricated transmission EAM with substrate removed is an excellent candidate to be used as an optical shutter for HD 3D imaging application.