• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.69.2-69.2
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• 2012

Graphene films have a strong potential to replace indium tin oxide anodes in organic light-emitting diodes (OLEDs), to date. However, the luminous efficiency of OLEDs with graphene anodes has been limited by a lack of efficient methods to improve the low work function and reduce the sheet resistance of graphene films to the levels required for electrodes. Here, we fabricate flexible OLEDs by modifying the graphene anode to have a high work function and low sheet resistance, and thus achieve extremely high luminous power efficiencies (37.2 lm/W in fluorescent OLEDs, 102.7 lm/W in phosphorescent OLEDs), which are significantly higher than those of optimized devices with an indium tin oxide anode (24.1 lm/W in fluorescent OLEDs, 85.6 lm/W in phosphorescent OLEDs). We also fabricate flexible white OLED lighting devices using the graphene anode. These results demonstrate the great potential of graphene anodes for use in a wide variety of high-performance flexible organic optoelectronics.

• Applied Chemistry for Engineering
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• v.23 no.3
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• pp.289-292
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• 2012

Au electrodes modified with self-assembled monolayers (SAMs) were used to control the work function of source/drain electrodes in triethylsilylethynyl anthradithiophene (TES ADT)-based organic thin film transistors (OTFTs). By using benzothiol (BT) and pentafluorobenzothiol (PFBT) SAMs, the hole injection barrier between Au and the highest occupied molecular orbital (HOMO) of TES ADT was controlled. After a solvent annealing, TES ADT OTFTs with PFBT SAM-treated Au electrodes were found to exhibit high field-effect mobilities of $0.05\;cm^2/Vs$ and on/off current ratios of $10^6$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.2
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• pp.69-74
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• 2016

In this study, we proposed an a-IGZO (amorphous In-Ga-Zn-O) TFT (thin-film transistor) with off-planed source/drain structure. Furthermore, two different electrode materials (ITO and Ti) were applied to the source and drain contacts for performance improvement of a-IGZO TFTs. When the ITO with a large work-function and the Ti with a small work-function are applied to drain electrode and source contact, respectively, the electrical performances of a-IGZO TFTs were improved; an increased driving current, a decreased leakage current, a high on-off current ratio, and a reduced subthreshold swing. As a result of gate bias stress test at various temperatures, the off-planed S/D a-IGZO TFTs showed a degradation mechanism due to electron trapping and both devices with ITO-drain or Ti-drain electrode revealed an equivalent instability.

• Journal of the Korean institute of surface engineering
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• v.37 no.6
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• pp.313-318
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• 2004

Vertically-aligned and uniformly-distributed CuO nanowires were formed on copper-coated Si substrates by wet chemical process, immersing them in a hot alkaline solution. The effects of hydrogen plasma treatment on the field emission characteristics of CuO nanowires were investigated. It was found that hydrogen plasma treatment enhanced the field emission properties of CuO nanowires by showing a decrease in turn-on voltage, and an increase in emission current density, and stability of current-voltage curves. However, the excessive hydrogen plasma treatment made the I-V curves unstable. It was confirmed by XPS (X-ray Photoelectron Spectroscopy) analysis that hydrogen plasma treatment deoxidized CuO nanowires, thereby the work function of the nanowires decreased from 4.35 eV (CuO) to 4.1 eV (Cu). It is thought that the decrease in the work function enhanced the field emission characteristics. It is well-known that the lower the work function, the better the field emission characteristics. The results suggest that the hydrogen plasma treatment is very effective in achieving enhanced field emission properties of the CuO nanowires, and there may exist an optimal hydrogen plasma treatment condition.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.355-355
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• 2010

We studied the dependence of the performance of schottky barrier metal-oxide-field effect transistors(SB MOSFETs) on the work function of source/drain metals. A strong impact of the various work functions and the light wavelengths on the transistor characteristics is found and explained using experimental data. We used an insulator of a high thickness (100nm) and back gate issues in SOI substrate, subthreshold swing was measured to 300~400[mV/dec] comparing with a ideal subthreshold swing of 60[mV/dec]. Excellent characteristics of Al/Si was demonstrated higher on/off current ratios of ${\sim}10^7$ than others. In addition, extensive photoresponse analysis has been performed using halogen and deuterium light sources(200<$\lambda$<2000nm).

• PNF and Movement
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• v.8 no.3
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• pp.9-16
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• 2010

Purpose : The purpose of this study was to investigate effects of kinesio taping of thigh muscle on isokinetic muscular function during closed kinetic chain exercise of lower extremity. Methods : Twenty healthy males were participated in this study. The isokinetic muscular function of closed kinetic chain were measured for peak torque, peak torque % body weight, average power, max rep tot work before and after application of kinesio taping on thigh muscles. Results : At $60^{\circ}/s$ peak force and peak force % body weight were significant increased in both extension(p<0.01) and flexion(p<0.001) after applying kinesio taping. At $180^{\circ}/s$ average power was significant increased in both extension and flexion after applying taping(p<0.001). At $240^{\circ}/s$ max rep tot work was significant increased in both extension(p<0.001) and flexion(p<0.05). Conclusion : This study suggests that application of kinesio taping on thigh muscle was more effective to improve isokinetic muscular function in closed kinetic chain exercise of lower extremity.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.482-484
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• 2005

The Modulation Transfer Function (MTF) is commonly used to characterize the spatial quality of imaging systems. This work is the attempt to measure the MTF at Nyquist frequency of the satellite imaging system what has 1m spatial resolution for KOMPSAT-2 image using the edge function. Artificial tarp targets are used in this study. A type of this tarp edge consists of two adjacent uniform bright and dark sides commonly used to test the performance of an optical system in edge function. The results from this work demonstrate the potential applicability of this method to estimate the response characteristics for KOMPSAT-2 that is scheduled to be launched.

• Journal of the Korean housing association
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• v.16 no.1
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• pp.65-72
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• 2005

With the changing consciousness of community people and the rising standard of living, there has recently been an emphasis on the creation of public facilities' new functions and their role as local community facilities. This changing trends are accordingly requiring a change in spatial structure of the public facilities. In this study, an analysis was conducted with 24 public facilities situated in the Buk-gu district of Daegu to identify the adequacy of their space scale after functional variation. The results of this study are summarized as follows. 1) The site area of public facilities has been being widened after functional variation since more spaces are needed to provide an outdoor resting space with community people, expand a parking space, and operate a community center. 2) The factors that had a direct effect on the change in the use of space are the reduced space for administrative work and the expanded scope of the community center's function. Specifically, the areas of activities for civil service and administrative work and for reserve forces have been reduced due to reduction of function, and floor division by each function group has been becoming stricter due to addition of a community center's function. 3) It was shown that in terms of the space for functions of public facilities, spaces for civil service and waiting have increased mostly after function variation. After functional variation, the scale of spaces for civil service and administrative work has been being planned within the range of $200\~300 m^2$, regardless of the number of population to be covered by public facilities. 4) The space for public use is showing the greatest increase in public facilities which have been built after functional variation. The major factors seem to be the increased moving passages, the expanded convenient facilities for community people, and the increased convenient facilities for disabled. Facilities scale plans have been being made more systematically, compared to the conventional facilities.

• Journal of Information Science Theory and Practice
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• v.10 no.3
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• pp.57-67
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• 2022

This study aims to understand human resource management in the Library of the House of Representatives of the Republic of Indonesia (DPR RI) during the COVID-19 pandemic. This institution had to change its work procedures, including its management of human resources. The research uses a qualitative approach with a case study method. Data was collected through interviews, observations, and document analysis, carried out from October to December 2020. The findings show that working from home practices had the following impacts: reduced ability to concentrate while working; many forced changes to the work programme; and problems of miscommunication due to work instructions being conveyed through a WhatsApp group. In response to the situation, the planning function of management was used to suspend the recruitment of interns; the organizing function was divided up tasks into two or three working days a week; the actuating function was seen in the willingness of leadership to motivate staff and to optimize resources by providing training; and the controlling function was realized in an online presence and online reporting mechanisms. It was concluded that the implementation of human resource management in the library was achieved through flexibility and staff empowerment. This involved carrying out initiatives and controlling their effectiveness in response to whatever changes were required by the latest pronouncements from government. Obstacles were still encountered in the implementation of these changes, especially in relation to the organizing function of management, where some conflict was seen between the DPR RI librarians.

• Journal of the Korean Home Economics Association
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• v.28 no.2
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• pp.73-89
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• 1990

The aim of the present study is to estimates the economic value of household work done by fulltime home makers, using alternative methods of valuation household work in Pusan Korea. Eight findings, five different methods -Self Estimation by Home Makers, Reservation Wage, Opportunity Cost, Individual function Cost, Replacement Cost(Visiting Housekeeper, Housekeeper, General Managemet, Housekeeper & General Management)- are tried for the estimation of economic value of household work. The results of this study can be outlined as follows : 1) The economic value of household work varies substantially by the methods of estimating. The averages are : 2) The economic value of household work varies with the level of education, ages, the number of children, the stage of FLC in all method of estimation, and the level of income in self estimation by home makers, Reservation wage. Specially, FLC revealed good explanation variable in method of estimation as input household work time. 3) The gap between two-day survey and three-day survey in household work time questionaire didn't so much.