• Korean Journal of Materials Research
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• v.8 no.7
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• pp.591-595
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• 1998

In this work, the freestanding GaN single crystalline substrates without cracks were grown by hydride vapor phase epitaxy (HVPE) and its some properties were investigated. The GaN substrate, having a current maximum size of 350 $\mu\textrm{m}$-thickness and 100$\textrm{mm}^2$ area, were obtained by HVPE growth of thick film GaN on sapphire substrate and subsequent mechanical removal of the sapphire substrate. A lattice constant of $C_o$= 5.18486 $\AA$ and a FWHM of DCXRD was 650 arcsec for the single crystalline GaN substrate. The low temperature PL spectrum consist of three excitonic emission and a deep D- A pair recombination at 1.8eV. The Raman E, (high) mode frequency was 567$cm^{-1}$ which was the same as that of strain free bulk single crystals. The Hall mobility and carrier concentration was 283$cm^3$<\ulcornerTEX>/ V.sand 1.1$\times$$10^{18}cm^{-3}$, respectively.

• Journal of the Korean Dietetic Association
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• v.20 no.4
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• pp.275-284
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• 2014

Reducing plate-waste for school lunches is an important strategy to guarantee adequate nutrition intakes by students as well as to protect the environment. This study was conducted to determine dieticians' perception of no-plate-waste day. The subjects were dieticians at 203 schools in Seoul and Kyeonggi-do. Among them, 132 schools (78.6%) operated no-plate-waste day once a week, 6.9% once a month, 10.8% twice a week, whereas 17.2% did not operate at all. According to dieticians, plate-waste per student on no-plate-waste day (mean 49.1 g) was lower than that on an ordinary day (mean 79.2 g). The most popular method to advertise no-plate-waste day was to notify it on the menu board (52.4%), followed by notifying it on the dining hall and the school website. The most frequently used reward on no-plate-waste day was a gift snack (67.3%), followed by complimentary stickers, awards, and GPA. The most common side effect of no-plate-waste day was students' abandoning foods (45.2%), followed by rejecting food and simplified menu. The most frequent barrier was insufficient recognition of necessity (39.3%), followed by shortage of manpower or budget and students and teachers' resistance. The dieticians at 35 schools without no-plate-waste day answered that they did not operate it due to 'no need perceived' and 'no budget' (31.4% and 31.4%, respectively). Based on this study, government and society should promote the need to reduce plate-waste by students and teachers as well as school administrators.

• Journal of Haehwa Medicine
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• v.24 no.1
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• pp.1-14
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• 2015

Objectives : The purpose of this study is to examine senior citizens' perception of medical welfare service in Daejeon, and to investigate the level of Korean Medicine University students' satisfaction about medical services that they have done. Methods : We visited Daejeon city hall and Dae jeon Seo-gu community health center, and interviewed them. After that we select two population and did two different surveys. First, to investigate the current state of medical services and medical welfare in Daejeon, we select neglected class senior citizens who were serviced at social welfare center. Second, we select Daejeon Korean Medicine University student to investigate the level of satisfaction about medical services and pre-education. In first population, we random select 25 of 34 senior citizen who visits mere social welfare center. In second population, we random select 78 of 115 Korean Medicine University student who belongs to medical welfare club. Results : We found some advantages and problems in medical services. A lot of senior citizen who were serviced at social welfare center showed high level of satisfaction about medical service. But there were few citizens who knows about health & medical welfare. And most Korean Medicine University student who services medical service to neglected class senior citizens showed high level of satisfaction. Conclusion : We concluded that medical welfare for senior citizen needs more publicizing. Because result of our survey, many senior citizens showed not only low level of recognition in medical welfare service, also showed low utilization rate in public health center. And most Korean Medicine University students were satisfied with themselves about medical service that they have done, it seemed medical service gives beneficial influence to not only senior citizen but also Korean Medicine University student.

• 한국HCI학회:학술대회논문집
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• 2008.02b
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• pp.205-209
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• 2008

The current representative supporting tool for seeing an exhibition is PDA, which is an information provider that is being activated in famous galleries in the world. It has been successful in making spectators' traffic line for exhibition free and in Overcoming time and spatial restrictions, but it still provides uniform information. And the field of its activities is 'inside' of an exhibition hall so it has some limitations in terms of two-directional communication. In order to overcome such limitations, this study intends to deduce applications for the activation of continuous communication in the changing exhibition environment from before spectators see an exhibition to after they see an exhibition, to design a prototype, and further, to improve the level of the exhibition culture.

• Journal of the Korean housing association
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• v.27 no.5
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• pp.55-63
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• 2016

This study intended to establish a direction for the revitalization of youth culture centers by examining the current status of youth centers operated in Daejeon and how they have been used. Four youth centers in Daejeon were visited and a survey was conducted targeting 180 people using the centers. Frequency, Mean, and ${\chi}^2$ analysis were performed by using SPSS statistics package, and major research outcomes are as follows; There were 6 youth culture centers in Daejeon and showed a lower construction rate of 7.4% on the basis of 81 up, myun and dong. Most youth centers were small, around $300-500m^2$ in total floor area, and accommodated 100-200 people, and the space comprised multipurpose hall, cafeteria, open space, club space, multimedia space, information service room, and guide booth. There were no sports spaces among the target facilities. So, it has created the need for physical activity space to promote health & development. Most users visited centers with their friends and simply to use the facilities, and the satisfaction with the facilities was relatively high at 4.32. The role of the local community and financial support of the government is required to activate the youth culture. Also, for the role of youth culture center, it was suggested that the youth culture center should develop program which corresponds with the level of the youth and boast the interest of the youth.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.11
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• pp.1758-1764
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• 2012

A large number of wire rope has been used in various inderstiries as Cranes and Elevators from expanding the scale of the industrial market. But now, the management of wire rope is used as manually operated by rope replacement from over time or after the accident.It is caused to major accidents as well as economic losses and personal injury. Therefore its time to need periodic fault diagnosis of wire rope or supply of real-time monitoring system. Currently, there are several methods has been reported for fault diagnosis method of the wire rope, to find out the feature point from extracting method is becoming more common compared to time wave and model-based system. This method has implemented a deterministic modeling like the observer and neural network through considering the state of the system as a deterministic signal. However, the out-put of real system has probability characteristics, and if it is used as a current method on this system, the performance will be decreased at the real time. And if the random noise is occurred from unstable measure/experiment environment in wire rope system, diagnostic criterion becomes unclear and accuracy of diagnosis becomes blurred. Thus, more sophisticated techniques are required rather than deterministic fault diagnosis algorithm. In this paper, we developed the fault diagnosis of the wire rope using probability density estimation techniques algorithm. At first, The steady-state wire rope fault signal detection is defined as the probability model through probability distribution estimate. Wire rope defects signal is detected by a hall sensor in real-time, it is estimated by proposed probability estimation algorithm. we judge whether wire rope has defection or not using the error value from comparing two probability distribution.

• Journal of Cadastre & Land InformatiX
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• v.47 no.2
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• pp.201-212
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• 2017

The purpose of this study is to identify the problems of the present status of the Jeollanamdo's geographical name task by analyzing it and to suggest ways to improve it. For this purpose, the theoretical review including the definition of the geographical name as the subject of the study is conducted. Also, by analyzing the current structure of geographical name, the enactment and improvement of the ordinance of the committee on geographical name, and the management of committee on geographical name etc, the problems of the geographical name task are derived and suggestions for improvement are proposed. The results of this study are as follows: First, as a plan to improve the professionalism of the organization and the officer in charge of the geographical name task, this study suggests the unification of the department in charge of geographical name task, the specialization of the official in charge, and the development of training and teaching materials related to the geographic name task. Secondly, in order to improve the ordinance and the management of the committee on geographical name, this study suggests the enactment and improvement of the ordinance of committee on geographical name, the guidance and the supervision of the establishment and operation of the committee on geographic name, the simplification of procedures of establishing and changing geographical name, and enactment of geographic name a Law.

• Proceedings of the Materials Research Society of Korea Conference
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• 2010.05a
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• pp.36.1-36.1
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• 2010

While the substrate-type solar cells with Cu(In,Ga)Se2 absorbers yield conversion efficiencies of up 20%[1], the highest published efficiency of Cu(In,Ga)Se2 superstrate solar cell is only 12.8% [2]. The commerciallized Cu(In,Ga)Se2 solar cells are made in the substrate configuration having the stacking sequence of substrate (soda lime glass)/back contact (molybdenum)/absorber layer (Cu(In,Ga)Se2)/buffer layer (cadmium sulfide)/window layer (transparent conductive oxide)/anti reflection layer (MgF2) /grid contact. Thus, it is not possible to illuminate the substrate-type cell through the glass substrate. Rather, it is necessary to illuminate from the opposite side which requires an elaborate transparent encapsulation. In contrast to that, the configuration of superstrate solar cell allows the illumination through the glass substrate. This saves the expensive transparent encapsulation. Usually, the high quality Cu(In,Ga)Se2 absorber requires a high deposition temperature over 550C. Therefore, the front contact should be thermally stable in the temperature range to realize a successful superstrate-type solar cell. In this study, it was tried to make a decent superstrate-type solar cell with the thermally stable ZnO:Al layer obtained by adjusting its deposition parameters in magnetron sputtering process. The effect of deposition condition of the layer on the cell performance will be discussed together with hall measurement results and current-voltage characteristics of the cells.

• The Plant Pathology Journal
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• v.29 no.3
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• pp.234-241
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• 2013

Polygalacturonase (PG) gene is a typical gene family present in eukaryotes. Forty-nine PGs were mined from the genomes of Neurospora crassa and five Aspergillus species. The PGs were classified into 3 clades such as clade 1 for rhamno-PGs, clade 2 for exo-PGs and clade 3 for exo- and endo-PGs, which were further grouped into 13 sub-clades based on the polypeptide sequence similarity. In gene structure analysis, a total of 124 introns were present in 44 genes and five genes lacked introns to give an average of 2.5 introns per gene. Intron phase distribution was 64.5% for phase 0, 21.8% for phase 1, and 13.7% for phase 2, respectively. The introns varied in their sequences and their lengths ranged from 20 bp to 424 bp with an average of 65.9 bp, which is approximately half the size of introns in other fungal genes. There were 29 homologous intron blocks and 26 of those were sub-clade specific. Intron losses were counted in 18 introns in which no obvious phase preference for intron loss was observed. Eighteen introns were placed at novel positions, which is considerably higher than those of plant PGs. In an evolutionary sense both intron loss and gain must have taken place for shaping the current PGs in these fungi. Together with the small intron size, low conservation of homologous intron blocks and higher number of novel introns, PGs of fungal species seem to have recently undergone highly dynamic evolution.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.389-389
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• 2012

Molybdenum is one of the most important materials used as a back ohmic contact for $Cu(In,Ga)(Se,S)_2$ (CIGS) solar cells because it has good electrical properties as an inert and mechanically durable substrate during the absorber film growth. Sputter deposition is the common deposition process for Mo thin films. Molybdenum thin films were deposited on soda lime glass (SLG) substrates using direct-current planar magnetron sputtering technique. The outdiffusion of Na from the SLG through the Mo film to the CIGS based solar cell, also plays an important role in enhancing the device electrical properties and its performance. The structure, surface morphology and electrical characteristics of Mo thin films are generally dependent on deposition parameters such as DC power, pressure, distance between target and substrate, and deposition temperature. The aim of the present study is to show the resistivity of Mo layers, their crystallinity and morphologies, which are influenced by the substrate temperature. The thickness of Mo films is measured by Tencor-P1 profiler. The crystal structures are analyzed using X-ray diffraction (XRD: X'Pert MPD PRO / Philips). The resistivity of Mo thin films was measured by Hall effect measurement system (HMS-3000/0.55T). The surface morphology and grain shape of the films were examined by field emission scanning electron microscopy (FESEM: Hitachi S-4300). The chemical composition of the films was obtained by the energy dispersive X-ray spectroscopy (EDX). Finally the optimum substrate temperature as well as deposition conditions for Mo thin films will be developed.