• Archives of design research
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• v.15 no.1
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• pp.93-100
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• 2002

The University's web library is a form of library that enables to deal with information about searching loaning, returning of books or data housed in it through web. With the advent of the network and multimedia following the entrance to an information-oriented society, we are experiencing a big change in how to communicate and acquire information. Massive multimedia information transmitted by image and moving picture through the network, made it possible to overstep the limit of the physical gap between information suppliers and users. Despite this important role, it is accompanied by problems such as copyright, scarcity of recognition, paralysis of infra, technical matters and reliability which demand development. In this thesis, according to the State University Evaluation Standards, search node and user interface by system used in 20 different universities possessing web-based library sites were compared are analysed. On the basis of this, an experimental user interface for web-based University libraries was produced, and various questionnaires and data leer this produced interface were collected, classified and analyzed. With the application of the results for the work above to the general search system interface of the web-based library, we proposed a new user interface that contains the following functions, such as location and loan condition of books, search frequency and steps for purchasing books inside the web library.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.12
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• pp.4467-4488
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• 2014

The bibliometric analysis is widely used for understanding research domains, trends, and knowledge structures in a particular field. The analysis has majorly been used in the field of information science, and it is currently applied to other academic fields. This paper describes the analysis of academic literatures for classifying research domains and for suggesting empty research areas in the telecommunications policy. The application software is developed for retrieving Thomson Reuters' Web of Knowledge (WoK) data via web services. It also used for conducting text mining analysis from contents and citations of publications. We used three text mining techniques: the Keyword Extraction Algorithm (KEA) analysis, the co-occurrence analysis, and the citation analysis. Also, R software is used for visualizing the term frequencies and the co-occurrence network among publications. We found that policies related to social communication services, the distribution of telecommunications infrastructures, and more practical and data-driven analysis researches are conducted in a recent decade. The citation analysis results presented that the publications are generally received citations, but most of them did not receive high citations in the telecommunications policy. However, although recent publications did not receive high citations, the productivity of papers in terms of citations was increased in recent ten years compared to the researches before 2004. Also, the distribution methods of infrastructures, and the inequity and gap appeared as topics in important references. We proposed the necessity of new research domains since the analysis results implies that the decrease of political approaches for technical problems is an issue in past researches. Also, insufficient researches on policies for new technologies exist in the field of telecommunications. This research is significant in regard to the first bibliometric analysis with abstracts and citation data in telecommunications as well as the development of software which has functions of web services and text mining techniques. Further research will be conducted with Big Data techniques and more text mining techniques.

• Journal of The Korean Association of Information Education
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• v.10 no.3
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• pp.299-306
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• 2006

The Ministry of Education and Human Resources Department of Korea have formulated various policy for development of teacher's ICT competence. But most of efforts expended upon ICT utilization currently, emphasize the ability which can handle computer skillfully than the ability for practical use in instruction, so that cannot induce distinct competence according to the duties and operations of teachers. This study aims to make scales for teacher's ability of ICT utilization in education of Korea. For the original purpose of evaluation, this tool made by job analysis and comparative studies with the existing appraisal standards. It can be the standards for evaluation of teacher's wholly duties on ICT applied education and proper self-evaluation tool for improvement of teacher's ability on ICT utilizing instruction. I processed measurement value of participant of Gwangju and Jeollanamdo area in this system and analyzed the level of teacher's abilities using ICT, a sex gap, regional difference, duty position difference and education career difference etc.

• Development and Reproduction
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• v.21 no.4
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• pp.379-389
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• 2017

Connexin (Cx) involves in the regulation of various physiological functions of tissue by forming a channel, a gap junction which allows direct cell-cell communication, between adjacent cells. The effect of a single subcutaneous treatment of estradiol benzoate (EB) or flutamide (Flu) at the weaning age on the expression of Cx isoforms in the adult caput epididymis was evaluated in this research. Using quantitative real-time PCR analysis, a low-dose of EB [$0.015{\mu}g/kg$ body weight (BW)] caused significant decreases of Cx30.3, Cx32, Cx40, Cx43, and Cx45 mRNA levels and no change of Cx26, Cx31, Cx31.1, Cx37 transcript levels. The treatment of a high-dose EB ($1.5{\mu}g/kg\;BW$) resulted in reduced expression of Cx30.3, Cx31, Cx43, and Cx45 but increased expression of Cx37 and Cx40. Expression of all Cx isoforms examined, except Cx31, was significantly increased by the treatment of a low-dose Flu ($500{\mu}g/kg\;BW$). However, the treatment of a high-dose Flu (5 mg/kg BW) led significant expressional suppression of Cx30.3, Cx31, Cx31.1, Cx32, Cx40, Cx43, and Cx45 but an increase of Cx37 transcript level. With the comparison of previous findings, the expression of Cx isoforms in the adult epididymis after the exposure to EB or Flu is likely differentially regulated in regional-specific and/or exposed postnatal age-specific manner.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.269-274
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• 2016

This paper proposes the development of a low frequency electronic hammer drive system that is used to prevent scaling or clogging in the hopper process. The electro-mechanical hammering driving method involves the generation of vibration and impact energy. The operation principles of the electromagnetic hammer were considered by parallel/series spring coefficient analysis and the amount of kinetic energy generated was calculated from the product of the equivalent spring constant, which is coupled with the E core and the gap of between the E core and I core. In addition, the Pulsation Driving algorithm was applied to the proposed electromagnetic hammer to obtain the maximizing kinetic energy. This algorithm was then implemented by a logical AND operation process and micro-controller (atmega128) built in functions with a timer interrupt and PWM generation function. The driving circuit of the electromagnetic hammer was designed using the H-bridge type IGBT circuit. The experimental test was performed by usefulness of the developed electromagnetic hammer systems with the acceleration measurement method. The experimental result showed that the proposed system has good kinetic energy generation performance and can be applied to the hopper process.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.97-97
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• 2010

We demonstrate the hybrid polymer-quantum dot based multi-functional device (Organic bistable devices, Light-emitting diode, and Photovoltaic cell) with a single active-layer structure consisting of CdSe/ZnS semiconductor quantum-dots (QDs) dispersed in a poly N-vinylcarbazole (PVK) and 1,3,5-tirs- (N-phenylbenzimidazol-2-yl) benzene (TPBi) fabricated on indium-tin-oxide (ITO)/glass substrate by using a simple spin coating technique. The multi-functionality of the device as Organic bistable device (OBD), Light Emitting Diode (LED), and Photovoltaic cell can be successfully achieved by adding an electron transport layer (ETL) TPBi to OBD for attaining the functions of LED and Photovoltaic cell in which the lowest unoccupied molecular orbital (LUMO) level of TPBi is positioned at the energy level between the conduction band of CdSe/ZnS and LiF/Al electrode (band-gap engineering). Through transmission electron microscopy (TEM) study, the active layer of the device has a p-i-n structure of a consolidated core-shell structure in which semiconductor QDs are uniformly and isotropically adsorbed on the surface of a p-type polymer core and the n-type small molecular organic materials surround the semiconductor QDs.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.12 no.2
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• pp.53-66
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• 1999

This study has been carried out to investigate the effects of Dojuksan on the renal functions and internal secretion system, as water balance, urine volume, urinary excretion of sodium and potassium, free water clearance, urinary excretion of creatinine, plasma levels of artrial natriuretic peptide (ANP), plasma levels of aldosterone and plasma renin activity, comparing experimental group which Dojuksan water extract were administrated with control group. Sprague-Dawley rats, about 200-250 g, were used for this experiment. The results of this study were as follows: 1. Water balance decreased significantly after the administration of Dojuksan water extract. 2. Urine volume increased significantly after the administration of $100{\mu}l$ Dojuksan water extract per 100g rat. 3. Urinary excretion of sodium increased significantly but urinary excretion of potassium did not change after the administration of Dojuksan water extract. 4. Free water clearance decreased significantly after the administration of Dojuksan water extract 5. Urinary excretion of creatinine increased significantly after the administration of Dojuksan water extract 6. Plasma renin activity did not change after the administration of Dojuksan water extract 7. Plasma levels of artrial natriuretic peptide (ANP) did not change after the administration of Dojuksan water extract 8. Plasma levels of aldosterone decreased significantly after the administration of 200 ${\mu}Dojuksan water extract per l00g rat The results suggest that Dojuksan increase the urinary excretion of sodium. and thus reduce the water balance, which resulted from suppression of sodium reabsorption into renal tubule by increasing glomerular filtration rate and decreasing aldosterone.

• Current Photovoltaic Research
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• v.7 no.1
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• pp.9-14
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• 2019

Carrier selective solar cell structure has allured curiosity of photovoltaic researchers due to the use of wide band gap transition metal oxide (TMO). Distinctive p/n-type character, broad range of work functions (2 to 7 eV) and risk free fabrication of TMO has evolved new concept of heterojunction intrinsic thin layer (HIT) solar cell employing carrier selective layers such as $MoO_x$, $WO_x$, $V_2O_5$ and $TiO_2$ replacing the doped a-Si layers on either front side or back side. The p/n-doped hydrogenated amorphous silicon (a-Si:H) layers are deposited by Plasma-Enhanced Chemical Vapor Deposition (PECVD), which includes the flammable and toxic boron/phosphorous gas precursors. Due to this, carrier selective TMO is gaining popularity as analternative risk-free material in place of conventional a-Si:H. In this work hole selective materials such as $MoO_x$, $WO_x$ and $V_2O_5$has been investigated. Recently $MoO_x$, $WO_x$ & $V_2O_5$ hetero-structures showed conversion efficiency of 22.5%, 12.6% & 15.7% respectively at temperature below $200^{\circ}C$. In this work a concise review on few important aspects of the hole selective material solar cell such as historical developments, device structure, fabrication, factors effecting cell performance and dependency on temperature has been reported.

• Journal of Digital Convergence
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• v.17 no.1
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• pp.179-187
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• 2019

Developing countries, including Africa, are experiencing very little human resources development due to the deprivation of equal educational opportunities, poor educational conditions, and the gap in information technology with developed countries. Developing countries that do not have excellent human resources are lagging behind in globalization competition with developed countries, and the problem of 'human resource development' in developing countries can not be avoided. In developing countries, education budgets are too low to meet education needs and compulsory education, and therefore they are not adequately responding to the increasing demand for education. The lack of education budget is due to the lack of education infrastructure. In this study, the NAS based server is configured to configure functions such as educational content and learning management, and the client area is presented with solutions for various media such as tablet, PC, and beam projector. And to support optimized e-learning services in developing countries by constructing a SCORM-based platform.

• Korean Journal of Optics and Photonics
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• v.30 no.2
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• pp.48-58
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• 2019

We investigate the signal-to-noise ratios (SNRs) of time-domain (i.e. pulsed illumination) and frequency-domain (i.e. chirped illumination) photoacoustic signals measured by a spherically focused ultrasound transducer for spherical absorbers. The simulation results show that the time-domain photoacoustic SNR is higher than that of frequency-domain photoacoustic signals, as reported in the previous literature. We understand the reason for this SNR gap between the two measurement modes by analyzing photoacoustic-signal spectra, considering the incident beam energy controlled by the maximum permissible exposure. As the result of this approach, we find that filtering off the DC term in the chirped signal's spectrum improves frequency-domain photoacoustic SNRs by up to approximately 5 dB. In particular, it is observed that photoacoustic SNRs are highly sensitive to an upper-frequency value of frequency filtering functions, and the optimal upper-frequency values maximizing the SNR are different in time- and frequency-domain photoacoustic measurements.