• Journal for History of Mathematics
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• v.28 no.6
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• pp.321-332
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• 2015

This paper is concerned with the convergence of double trigonometric series and Fourier series. Since the beginning of the 20th century, many authors have studied on those series. Also, Ferenc $M{\acute{o}}ricz$ has studied the convergence of double trigonometric series and double Fourier series so far. We consider $L^p(T^2)$-convergence results focused on the Ferenc $M{\acute{o}}ricz^{\prime}s$ studies from the second half of the 20th century up to now. In section 2, we reintroduce some of Ferenc $M{\acute{o}}ricz^{\prime}s$ remarkable theorems. Also we investigate his several important results. In conclusion, we investigate his research trends and the simple minor genealogy from J. B. Joseph Fourier to Ferenc $M{\acute{o}}ricz$. In addition, we present the research minor lineage of his study on $L^p(T^2)$-convergence.

• Journal of radiological science and technology
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• v.37 no.2
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• pp.75-84
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• 2014

In this study, we surveyed the current status, satisfaction and demand of radiologic technologist continuing education for 93 radiologic technologists who participated in the continuing education. To understand the current status and general evaluation and to find out the improvement direction, survey was conducted on 3 categories: participation, satisfaction and demand of continuing education. In addition, we analyzed the continuing education implementation status and the management system by collecting related regulations. As a result, the education completion rates of radiologic technologists from 2010 to 2012 were respectively 42.6%, 43.4% and 34.2%; the rates were similar to other medical technician's average education completion rates. According to the survey, in case of participation, the most frequent answer was 'more than five times less than 10 times per year' with 48.4% and in satisfaction section, the most common answer was 'Average(3)' with 34.4%. In demand of continuing education section, 32.8% of the respondents chose 'Clinical skill training in major field'. In the results of this research, continuing education needs to be managed in the direction of helping radiologists improve their personal ability and self development. Furthermore, to meet the demand of radiologists, the quality of continuing education should be improved to satisfy the educatee.

• Journal of the Korean Applied Science and Technology
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• v.40 no.3
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• pp.425-434
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• 2023

An analysis was conducted on landfill gas generation and surface emission by major routes for three landfill sites of S Landfill in the metropolitan area. LS1, which had a total landfill gas generation ratio of 10.9%, accounted for 49.4% of the total surface emissions. The total surface emission of methane alone was 13.6 Nm³/min in the three landfill sites. Among them, the surface emission of methane at LS1, LS2, and LS3 was 8.4(61.7%), 4.0(29.4%), and 1.2 Nm³/min(8.9%), respectively. By emission path in the upper, slope, and dike, it was 7.3(53.2%), 6.4(46.7%), and 0.02 Nm³/min(0.1%). The dike section of the major surface emission areas showed the largest oxidation rate at 87.5%, followed by the upper at 72.3%, and the slope at 71.8%. Based on methane generation, LS1 had the largest surface emission contribution rate, with 61.7% of the total by S Landfill. By major emission path, the slope section of LS1 accounted for 41.7% of the total, the upper section of LS2 24.4%, and the upper section of LS1 20.0%, which accounted for 86.1% of the total methane surface emission of S Landfill. Therefore, it is concluded that intensive management will be necessary.

• Journal of the Korea Convergence Society
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• v.5 no.2
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• pp.19-23
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• 2014

In this study, the air resistance is studied by using flow analysis near automotive body due to the its shape. Flow velocities of airs entering into inlet plane are two kinds of 70 km/h and 100 km/h. Air resistance in case of high speed driving(100 km/h) becomes higher than regular speed driving(70 km/h) and the resistance in case of the car with wider cross section at front side becomes higher than narrower cross section. By using this analysis result, the shape of automotive body can be effectively designed in order to reduce the air resistance.

• Transactions on Electrical and Electronic Materials
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• v.14 no.4
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• pp.216-220
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• 2013

The etching characteristics of indium zinc oxide (IZO) in $Cl_2/Ar$ plasma were investigated, including the etch rate and selectivity of IZO. The IZO etch rate showed non-monotonic behavior with increasing $Cl_2$ fraction in the $Cl_2/Ar$ plasma, and with increasing source power, bias power, and process pressure. In the $Cl_2/Ar$ (75:25%) gas mixture, a maximum IZO etch rate of 87.6 nm/min and etch selectivity of 1.09 for IZO to $SiO_2$ were obtained. Owing to the relatively low volatility of the by-products formation, ion bombardment was required, in addition to physical sputtering, to obtain high IZO etch rates. The chemical state of the etched surfaces was investigated with X-ray photoelectron spectroscopy. These data suggested that the IZO etch mechanism was ion-enhanced chemical etching.

• Journal of the Korean Society of Industry Convergence
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• v.5 no.3
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• pp.165-171
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• 2002

The thermosyphon has been used as a heat transmission device in the heat recovery of low level energy and cooling for heat generating equipments. Many studies on the working fluids and wicks have been reported to improve the heat transfer efficiency of the thermosyphon. A low temperature heat pipe with acetone is chosen in the present study to compare the heat transfer characteristics due to pouring amount of working fluid, magnitude of power supplied and tilt angles. The thermosyphon made ⵁ$15.88{\times}0.8t{\times}600mm$ of copper, evaporation section 200mm, insulation section 25mm, condensation 375mm. Heat transfer rate of the thermosyphon increase as magnitude of power supplied increase and observe dry out phenomenon at 5~10% of pouring amount of working fluid. So thermosyphon at the 150kJ/s judged to need 12% or more. Heat transfer rate of the thermosyphon have nothing to do with tilt angles. Dry out phenomenon of the thermo syphon makes it possible that a low temperature thermosyphon may be used to control temperature and heat transfer of a system when the critical quantity of a working fluid is supplied in the thermosyphon.

• Journal of the Korean Society of Industry Convergence
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• v.3 no.3
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• pp.219-228
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• 2000

In order to evaluate the applicability of thermosyphon as an equipment of heat transfer to the case where natural of low temperature and low density is necessary and to propose the possibility of using natural energy being clean and inexhaustible, a thermosypon using methanol as working fluid was constructed and its transfer characteristics were analysed. The wall temperature of the thermosyphon was maintained relatively uniform after rapid increase until after being heated about ten minutes regardless of the level of input powers to the evaporating section. Inner pressure of the thermosyphon increased rapidly until after ten minutes, and then increased slowly depending on the level of input power. But heat transfer coefficient of the condensible section decreased in inverse proportion to input powers of 250~300W, showing $1008.3{\sim}829.8W/m^2{\cdot}^{\circ}C$. For the input powers of the thermosyphon within the range of 100~250W, heat transferred and heat flux increased relatively linearly showing, in the case of input powers of 250~300W, heat transfer efficiency considerable increased, showing 63.8%.

• Transactions on Electrical and Electronic Materials
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• v.15 no.1
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• pp.49-54
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• 2014

In this study, we carried out an investigation of the etch characteristics of silicon (Si) film, and the selectivity of Si to $SiO_2$ in $SF_6/O_2$ plasma. The etch rate of the Si film was decreased on adding $O_2$ gas, and the selectivity of Si to $SiO_2$ was increased, on adding $O_2$ gas to the $SF_6$ plasma. The optical condition of the Si film with this work was 1,350 nm/min, at a gas mixing ratio of $SF_6/O_2$ (=130:30 sccm). At the same time, the etch rate was measured as functions of the various etching parameters. The X-ray photoelectron spectroscopy analysis showed the efficient destruction of oxide bonds by ion bombardment, as well as the accumulation of high volatile reaction products on the etched surface. Field emission auger electron spectroscopy analysis was used to examine the efficiency of the ion-stimulated desorption of the reaction products.

• Transactions on Electrical and Electronic Materials
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• v.14 no.2
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• pp.67-70
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• 2013

In this study, we changed the input parameters (gas mixing ratio, RF power, DC bias voltage, and process pressure), and then monitored the effect on TiN etch rate and selectivity with $SiO_2$. When the RF power, DC-bias voltage, and process pressure were fixed at 700 W, - 150 V, and 15 mTorr, the etch rate of TiN increased with increasing $CF_4$ content from 0 to 20 % in $CF_4$/Ar plasma. The TiN etch rate reached maximum at 20% $CF_4$ addition. As RF power, DC bias voltage, and process pressure increased, all ranges of etch rates for TiN thin films showed increasing trends. The analysis of x-ray photoelectron spectroscopy (XPS) was carried out to investigate the chemical reactions between the surfaces of TiN and etch species. Based on experimental data, ion-assisted chemical etching was proposed as the main etch mechanism for TiN thin films in $CF_4$/Ar plasma.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.1
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• pp.69-78
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• 2023

For this purpose, the research is to study the architectural characteristic of SooMaJaiJeon which is one of the DongHwaSa in the traditional wooden architecture by dividing it into three section-bracket, roof structure and frame structure. This study is largely divided into four stage-section do subject, research and actual measurement and conclusion. The whole process was consistently executed through detailed steps. The com position of this study is as follows. The 1^st chapter-the purpose, background, method, object and range of the research. The 2^nd chapter-the history of SooMajaiJeon. the 3^rd chapter-the structure of Dapo-style bracket has generally considered, the frame structure of Dapo-style, vertical and horizontal member and podium, the characteristic of bracket with member and the structure, design of bracket, roof structure. In the 4^th chapter, the conclusion of this study has been summarized, Dapo-style is the building that has deep symbolism and structural characteristic of traditional wooden architecture. The frame structure has a dominant regional characteristic and a typical part of typological classification in SooMaJaiJeon.