• Bulletin of the Korean Chemical Society
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• v.29 no.6
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• pp.1211-1216
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• 2008

A series of DTPA-bis(amides) functionalized by pyridine (1a-c) and N-phenylpicolinamide) (1d-e) and their Gd(III)-complexes of the type [Gd(1)($H_2O$)]·x$H_2O$ (2a-e) were prepared and characterized by analytical and spectroscopic techniques. Potentiality of 2a-e as contrast agents for magnetic resonance imaging (MRI CA) was investigated by measuring relevant physicochemical properties and relaxivities and compared with [Gd(DTPA-BMA)($H_2O$)] (DTPA-BMA=N,N''-di(methylcarbamoylmethyl)diethylenetriamine-N,N',N''-triacetate) ($Omniscan^{(R)}$). The R1 relaxivities of aqueous solutions of 2a-c are in the range of 3.33 -5.02 $mM^{-1}$$sec^{-1}$, which are comparable with those of $Omniscan^{(R)}$ (r1=4.58 $mM^{-1}sec^{-1}$). Complexes 2d-e, insoluble in water, exhibit relatively higher R1 values (8.1- 8.3 $mM^{-1}sec^{-1}$) in HP-$\beta$-CD solutions.

• Journal of Sensor Science and Technology
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• v.26 no.3
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• pp.155-159
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• 2017

The analog-to-digital converter (ADC) is an important component in various fields of sensor signal processing. This paper presents an expandable flash analog-to-digital converter (E-flash ADC) for sensor signal processing using a comparator, a subtractor, and a multiplexer (MUX). The E-flash ADC was simulated and designed in $0.35-{\mu}m$ standard complementary metal-oxide semiconductor (CMOS) technology. For operating the E-flash ADC, input voltage is supplied to the inputs of the comparator and subtractor. When the input voltage is lower than the reference voltage, it is outputted through the MUX in its original form. When it is higher than the reference voltage, the reference voltage is subtracted from the input value and the resulting voltage is outputted through the MUX. Operation of the MUX is determined by the output of the comparator. Further, the output of the comparator is a digital code. The E-flash ADC can be expanded easily.

• Journal of Korean Society on Water Environment
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• v.22 no.1
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• pp.66-73
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• 2006

The purpose of this study was done to evaluate degradation characteristics of non-biodegradable organic matters including aromatic compounds in livestock wastewater using CFZ process. The CFZ process is consisted of coagulation/sedimentation, Fenton oxidation and zeolite adsoption process. degradation charateristics of each treatment water including livestock wastewater were analyzed by UV scanning, FT-IR and GC/MS. After coagulation/sedimentation process as 1st treatment, non-biodegradable matters remained after 1st treatment were removed by using OH radical produced in Fenton oxidation process. As a result of treatment using these processes, NBDCOD removal efficiency was over 90%. Increase of $E_2/E_3$ ratio (absorbance at 250 and 365 nm) in each treatment water means that aromaticity of livestock wastewater decreased. In case of GC/MS, most aromatics or polynuclear aromatics like benzene, phenol and scatol in livestock wastewater almost wasn't detected after oxidation using OH radical.

• Journal of the Korean institute of surface engineering
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• v.47 no.6
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• pp.341-346
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• 2014

Ga-doped ZnO (GZO) single layer and $SiO_2/GZO$ bi-layered films were deposited on Polycarbonate(PC) substrate by radio frequency magnetron sputtering. Influence of the structural, electrical, and optical properties of the films was considered. We have considered the influence of electron irradiation energy of 450 and 900 eV on the stuctural, electrical and optical properties of $SiO_2/GZO$ thin films. The optical transmittance in a visible wave length region increased with the electron irradiation energy. The electrical resistivity of the films were dependent on the electron's irradiation energy. The $SiO_2/GZO$ films irradiated at 900 eV were showen the lowest resistivity of $7.8{\times}10^{-3}{\Omega}cm$. The film which was irradiated by electron at 900 eV shows 84.3% optical transmittance and also shows lower than contact angle of $58^{\circ}$ in this study.

• Journal of The Korean Association of Information Education
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• v.12 no.3
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• pp.333-345
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• 2008

The purpose of the research is to investigate the perception of corporate and e-Learning institute on ubiquitous society and learning environment in the context of human resource development. In addition, the study aims to analyze their recognition of u-Learning's components into the level of significance and actualization. The total of 118 institutes were participated in the research survey among the 144 e-learning certified institutes from the Ministry of Labor. The research includes the results of survey and implications on the area of human resource development.

• Journal of Information Technology Services
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• v.8 no.3
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• pp.111-134
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• 2009

We are living it what is referred to as the Digital Era; a time in which communication through the computer medium has deeply infiltrated our everyday lives and is now equivalent to face-to-face communication. In other words, e-communication is the core factor of knowledge sharing, for not only individuals but also for corporations, and its efficiency has increased gradually. At this time, studies on the factors affecting the outsourcing performance of e-communication channel services are gaining importance. Therefore, the purpose of this study is to empirically analyze the effects of the system, information, and service quality on the user satisfaction and user trust of e-communication channel outsourcing, as well as the effects of user satisfaction and user trust on the outsourcing performance of both individuals and organizations. In the results of the empirical study, the system, Information, and service quality appear to have a significant effect on both user satisfaction and user trust. In addition, user satisfaction and user trust appear to also have a significant effect on the outsourcing performance of both Individuals and organizations.

• Asia Marketing Journal
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• v.14 no.3
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• pp.7-26
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• 2012

The success story of E-mart fascinated many academics and practitioners alike. Though E-mart began as a nameless discount store in Chang-dong, Seoul in 1993, it has transformed itself into a leading distribution company and one of the most powerful brands in Korea. Surprisingly, it achieved the great success against the two crises it met: the national economic crisis and the invasion of the global giant Walmart. The main objective of this case study is to formally examine how E-mart overcame the two crises. More specifically, this case study highlights the ways with which E-mart turned those difficulties into opportunities for growth. In our examination of the E-mart case, we could clearly see E-mart's competence and spirit that allowed it to turn crises into advantageous opportunities. E-mart attracted the customers who wanted value-oriented consumption by its positioning as the "Lowest price discount store", when consumer sentiment was frozen under the economic crisis. Furthermore, when a large-scale foreign discount store like Walmart entered the Korea market, E-mart built its core competencies as the 'Korean style discount store'. These ingenious positioning and efforts resulted in E-mart taking over their archrival, Walmart, and forced the global Goliath to exit the Korean market. The case of E-mart's effective crisis management teaches many important lessons and a few core lessons that apply to many companies. One such lesson is the importance of positioning which enabled E-mart to turn crises into opportunities. Granted, the strategy of positioning as the 'Korean style discount store', or 'Lowest price discount store' was possible due to overall support with cost reduction, development and management of their own system, an apprentice educate system, etc. based on an excellent selection of location of the store and efficient distribution systems. Still, the positioning strategy of E-mart was truly ground breaking in distancing itself from its competitors. The lessons from E-mart will help those companies currently in a stagnant situation or a crisis to turn their obstacles into great success.

• The Korea Journal of Herbology
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• v.28 no.6
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• pp.15-23
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• 2013

Objectives : To clarify the possible effects of Sinapis Semen and Raphani Semen on the development of pulmonary eosinophilic inflammation in a asthmatic mouse model. Methods : BALBav/c mice were sensitized to OVA followed intratracheally and by aerosol allergene challenges. We investigated the effect of Sinapis Semen and Raphani Semen on airway hyperresponsiveness, eosinophiic infitratio, immune cell phenotype, The2 cytokine product, and OVA-spedific IgE production. Results : Total lung cells, eosinophils, and lung leukocytes, OVA specific IgE levels, and Th 2cytokine levels such as IL-5, IL-13, IL-17, TNF-alpha, and eotaxin in BALF were reduced compared with those of OVA sensitized asthma mice (control). The absolute numbers of $CD3^+$, $CD3^+/CD69^+$, $CD3^-/CCR3^+$, $CD4^+$, $CD8^+$, $Gr-1^+/CD11b^+$, $B220^+/CD22^+$, $B220^+/IgE^+$ cells in lung tissiues significantly reduced compared to those of control. Specially total lung cells in BALF and the absolute number of $CD3^+/CD69^+$ and, $B220^+/IgE^+$ cells in lung tissiue effectively reduced in Sinapis Semen plus Raphani Semen compared to those of Sinapis Semen and Raphani Semen. Conclusions : These results indicate that Sinapis Semen plus Raphani Semen has deep inhibitory effects on airway inflammation and hyperresponsiveness in asmatic mouse model and also has effect of suppression of IL-5, IL-13, IL-17, OVA specific IgE production in BALF. The results verified that Sinapis Semen, Raphani Semen, and Sinapis Semen plus Raphani Semen could act as a immunomodulator which possess anti-inflammatory and anti-asthmatic property by modulating the relationship of Th1/Th2 cytokine imbalance.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.10a
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• pp.41.1-41.1
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• 2011

본 연구에서는 MOCVD법으로 사파이어 기판위에 u-GaN를 성장한 후 Mg을 도핑시켜 p-GaN를 성장하고, RF 스퍼터를 이용하여 n-ZnO를 도포하여 n-ZnO/p-GaN 이종접합을 형성한 후 진공증착기를 이용하여 Au/Ni를 증착시켜 발광다이오드(LED)를 제작하고 전기 광학적 특성을 조사하였다. 두께가 500 nm인 u-GaN 위에 성장된 p-GaN의 운반자 농도는 $1.68{\times}10^{17}\;cm^{-3}$ 이었다. 그리고 150, 300 nm 두께의 p-GaN에 대하여 측정된 DXRD 반치폭은 각각 450 arcsec, 396 arcsec 이었고, 상온에서 2.8~3.0 eV 영역에서 Mg 억셉터와 관련된 광루미네센스가 검출되었다. RF 스퍼터링에 의해 0.7 nm/min의 속도로 증착된 n-ZnO 박막은 증착 두께에 따라 비저항이 27.7 $m{\Omega}{\cdot}cm$ 에서 6.85 $m{\Omega}{\cdot}cm$ 까지 감소하였다. 그리고 n-ZnO 박막은 (0002)면으로 우선 배향되었으며, 상온에서 에너지갭 관련된 광루미네센스가 3.25 eV 부근에서 주되게 검출되었다. n-ZnO/p-GaN 이종접합 LED의 전류전압 특성곡선은 다이오드 방정식에 만족하는 특성을 나타내었다. 다이오드 지수는 3 V 이하 영역에서 1.64, 3~5 V 영역에서 0.85이었다. 그리고 5 V 이상 영역에서 공간전하의 제한을 받았으며, 다이오드 지수는 3.36이었다. 한편, 역방향 전류전압 특성은 p-GaN 박막의 두께에 영향을 받았으며, p-GaN 박막의 두께가 150, 300 nm 일 때 각각의 누설 전류는 $1.3{\times}10^{-3}$ mA와 $8.6{\times}10^{-5}$ mA 이었다. 상온에서 측정된 EL 스펙트럼의 주된 발광피크는 430 nm이었고, 반치폭은 49.5 nm이었다.

• Journal of Life Science
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• v.20 no.2
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• pp.219-224
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• 2010

This study was carried out to develop the breeding and cultivation of Allium grayi by investigating its natural habitats in Korea. The number of sunny, half-shady, and shady natural habitats were 194 (64.0%), 96 (31.7%), and 13 (4.3%), respectively. Natural habitats included upland (51.2%), Buddhist temple (18.8%), mountain (11.6%), roadside (7.9%), river (5.9%), paddy field (2.3%), and seashore (2.3%). Natural habitats ranged widely in all areas between $33^{\circ}N{\sim}38^{\circ}N$ and $126^{\circ}E{\sim}130^{\circ}E$. Self-generation patterns included growing spontaneously with a 1~10m distance between plants, and there were 3~5 bulbils around each bulb. The sprout stage began in September and continued until March of next year in natural habitats. The bolting period was May, with the following three patterns: tuber (59.2%), flower and tuber (24.7%), and flower (16.1%).