• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.11
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• pp.1230-1233
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• 2004

The ITO thin films were prepared by the FTS(Facing Targets Sputtering) system. The ITO thin films are deposited by changing the input current and working gas pressure. Then, electric characteristics, transmittance and surface roughness of ITO thin films were measured by Hall effect measurement, UV-VIS spectrometer and AFM. As a result, the ITO thin film was fabricated with resistivity 6xl0$^{-4}$ Ωㆍcm, carrier mobility 52.11 $\textrm{cm}^2$/Vㆍsec, carrier concentration 1.72 x $10^{20}$ $cm^{-3}$ transmittance over 85 % of ITO film at working gas pressure 1 mTorr and input current 0.6 A.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.11
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• pp.2076-2082
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• 2011

The goal of this paper is to find an operating conditions of the single direct ethanol fuel cell such as the cell temperature, and flow rates of ethanol and oxygen. To investigate the output characteristics, the electrical current increased from 0[A] with interval of 0.001[A] every 2[s], and the cell voltage was increased until the voltage became 0.05[V]. Related to the effect of the cell temperature, the output characteristics both voltage and power were increased upto 80[$^{\circ}C$] according to the increase of the current density, but those were decreased over that temperature. In addition, the optimal flow rate of ethanol in anode was identified as of 2[mL/min] due to the dependence of generation rate such as the hydrogen ion and electron. And the flow rate of oxygen in cathode was desirable to about 300[sccm/min], it might be affected by the chemical reaction rate of the water formation among hydrogen ion, electron, and oxygen. Consequently, the fundamental conditions were identified in this work, and it will be carried out to find the best conditions of membrane by the effect of the plasma surface treatment, and the effect of other catalysts except for a platinum.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.6
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• pp.40-44
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• 2014

In this paper, maximum power is the lowering device using the facility's energy use and peak load electricity through analyzing attitude should like to make it reduce its power base rate. Simulator to manage the demand for power, a maximum electric power base power from electronic watt-hour meters by a device's signal, predictive power, the current power by computing the goal of power for less than Maximum peak power and peak shift, so that you can manage, and peak York, which role you want a cut Metal heat treatment result which analyzes the data, demand for electricity company over the years of analyzing the characteristics of each load, and effects and Reducing power consumption device every month identified seven Sequence control to the load system and successful power control is about showing that the defined goals.

• Journal of Information Technology Services
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• v.17 no.2
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• pp.143-163
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• 2018

The business models has a great impact on the successful management of enterprises. Business environment has been shifting from industrial economy to knowledge-based economy. Enterprises go through numerous trials for successful management in the changing environment. Along with trial tests, research areas have been growing simultaneously. Although many researches have been conducted with regard to business models, it is very insufficient to systematically analyze the knowledge flow of research. Accordingly, successive researchers who want to study the business model may find it difficult to establish the orientation of future application research based on understanding the process of changing the knowledge structure that have accumulated so far. This study is intended to determine the current state of the business model research and to understand the process of knowledge structure changes in keywords that appear in 2,667 business model articles in the SCOPUS database. Identifying the knowledge structure has been completed through social network analysis, a methodology based on the 'relationship', and the changes in the knowledge structure were identified by classifying them into four different periods. The analysis showed that, first, the number of business model co-author increases over time with the need for academic diversity. Second, the 'innovation' keyword has the biggest center in the network, and over time, the lower-rank keyword which was in the former period has emerged as the top-rank keyword. Third, the cohesiveness group decreased from 12 before 2000 to 5 in 2015 and also the modularity decreased as well. Finally, examining characteristics of study area through a cognitive map showed that the relationships between domains increased gradually over time. The study has provided a systematic basis for understanding the current state of the business model research and the process of changing knowledge structure. In addition, considering that no research has ever systematically analyzed the knowledge structure accumulated by individual researches, it is considered as a significant study.

• Journal of the Korean Data and Information Science Society
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• v.21 no.6
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• pp.1031-1039
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• 2010

The decathlon is an athletic event consisting of ten track and field events. Events are held over two consecutive days and the winners are determined by the combined performance in all. Performance is judged in meters, centimeters, minutes, and seconds. However, how to convert results into points is a difficult and controversial issue. We explored the distribution of decathlon results from the 1991 to 2009 using top 200 decathlons in the Olympic games and word championships. The conclusion is that the results from top level decathlon competition are normally distributed, and the current scoring system does not have the property that the performance with same difficulty should get same points. A new model for evaluating the decathlon score has been applied that display uniform characteristics over all events in order to meet the notion of allroundness. The proposed model is uniform over the events and support self-stabilization.

• Journal of the Korea Convergence Society
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• v.2 no.2
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• pp.35-45
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• 2011

Recently, with the increasement of the interest about global warming, pollutions, and so on, a number of distributed generations(DGs) such as photovoltaic(PV) and wind power(WP), are interconnected with distribution systems. However, installing of DGs makes power flow changes such as directions, one-direction to bi-direction, and increasing/decreasing of fault current. Therefore, it may cause the critical problems. This paper proposes an evaluation algorithm for bi-directional protection coordination and presents an evaluation system for protection coordination based on this algorithm. Additionally, the result shows that the existing method may cause critical problems, and also the effectiveness of proposed method is verified.

• Ocean and Polar Research
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• v.36 no.1
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• pp.59-69
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• 2014

The long-term mooring performed at a KOGA station, located at about $30^{\circ}20^{\prime}N$, $126^{\circ}12^{\prime}E$ in the East China Sea shelf, shows some different behaviors between "semi-diurnal" and "diurnal currents" defined as the currents with periods around, respectively, a half day and a day. They appear to be predominantly tidal having significant coherences with sea level changes around the semi-diurnal and diurnal frequencies. The "semi-diurnal current" is strongly barotropic all year round. However, contrastingly, it is largely baroclinic in summer in the area about 70 km nearer to the continental slope, referred to as the "slope-area", as was found in previous current observations. The "diurnal current" of tidal origin is strongly barotropic in winter. In spring and summer, however, it becomes more baroclinic although it still remains largely barotropic, also showing more of its barotropic nature than in the "slope-area". The inertial oscillation contributing to the "diurnal current" appears to be more prominent when the current is baroclinic, indicating the important role played by stratification in generation of inertial oscillations. Downward energy propagation of inertial oscillation is not observed, suggesting that it is not created at the surface by wind. Considering that the study area is both near a critical latitude and proximity to the continental slope, it is suggested that parametric subharmonic instability (PSI) plays a significant role in creating the baroclinic inertial oscillation.

• Journal of Software Assessment and Valuation
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• v.16 no.2
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• pp.109-115
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• 2020

In this paper, the problem that occurs when negative voltage is generated using an inexpensive buck device in an IT device that is supplied with a single power by an adapter or battery is analyzed. For the cause analysis, the principle of operation of the buck device and the principle of the inverter circuit were examined, and the circuit characteristics of the inverter circuit were analyzed using the buck device. As a result of the analysis, it was confirmed that the inverter circuit using the buck device initially needs a large starting current, and in particular, in the case of a current capacity that is less than the starting current in the circuit that supplies power, it was confirmed that it could fall into a state similar to the latch-up phenomenon. In order to confirm the analysis result, an experimental circuit was constructed and the input current was checked. If the supply current is sufficient, it is confirmed that over-current flows and starts. If the supply current is insufficient, the circuit cannot start and a latch-up phenomenon occurs.

• Electrical & Electronic Materials
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• v.7 no.2
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• pp.145-151
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• 1994

The multi-dielectric layer SiOz/Si3N4/SiO2(ONO) is used to scale down the memory device. In this paper, the change of composition in ONO layer due to the process condition and the conduction mechanism are observed. The composition of the oxide film grown through the oxidation of nitride film is analyzed using auger electron spectroscopy(AES). AES results show that oxygen concentration increases at the interface between oxide and nitride layers as the thickness -of the top oxide layer increases. Results of I-V measurement show that the insulating properties improve as the thickness of the top oxide layer increases. But when the thickness of the nitride layer decreases below 63.angs, insulating peoperties of film 28.angs. of top oxide and film 35.angs. turn over showing that insulating property of film 28.angs. of top oxide is better than that of film 35.angs. of top oxide. This phenomenon of turn over is thought as the result of generation of surface state due to oxygen flow into nitride during oxidation process. As the thickness of the top oxide and nitride increases, the electrical breakdown field increases, but when the thickness of top oxide reaches 35.angs, the same phenomenon of turn over occurs. Optimum film thickness for scaled multi-layer dielectric of memory device SONOS is estimated to be 63.angs. of nitride layer and 28.angs. of top oxide layer. In this case, maximum electrical breakdown field and leakage current are 18.5[MV/cm] and $8{\times}{10^-12}$[A], respectively.

• Culinary science and hospitality research
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• v.11 no.3 s.26
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• pp.151-165
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• 2005

The current study aims to help field managers of companies providing foodservice for institutions to establish the more appropriate cost management strategy by analyzing the cost structure of foodservice center in institutions by operating types and the number of people served. From the result analyzing 161 foodservice centers, the number of factories was highest with 39.8% while offices 26.7%, schools 20.5%, and hospitals 13%. In terms of the number of people served, below 500 persons was 27.6%, 501${\sim}$l,000 persons was 23.9%, 1,001${\sim}$2,000 persons was 22.7%, and over 2,001 persons was 25%. In the demographic characteristics of managers, women occupied over 92%. The reason for this is usually dieticians perform management duties. For the age of workers, 70.8% were older than 40s, which ran become the cause of a rise in cost by causing the decrease of productivity by aging. Therefore, appropriate countermeasures are required. In case of workers in production, women occupy 962 persons (82.2%) rating absolute majority like mangers. This is because cooks are in charge of almost every producing activity of meal facilities. In addition, more than 72.9% of workers in production were over 40 years old, which requires diversified studies to promote efficiency of production associated with the aging problem. In proportion of sales compared with cost material cost presented the highest percentage with 54.5% while labor cost 28.3%, general expenses 9.6% and business profit 7.6%.