• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.3
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• pp.349-358
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• 1997

meta-Nitroaniline(mNA) crystals were grown from the supercooled melt for the first time. A seed was introduced into the purified mNA melt of 100 ml 0.1 K above the melting temperature ($T_m$ : $112.0^{\circ}C$) and crystal was grown at constant supercooling of 0.1 K. The melt was stirred . mechanically and the crystal was also rotated while the growth proceeds. mNA crystals of size up to $20{\times}15{\times}15 \textrm {mm}^3 and of very high perfection could be grown for the period of one day. The bottom half of the crystal faces are well-faceted and covered by {111} and {021} faces, while the faces of the top half are not well defined. The overall crystal morphology was characterized by the unidirectional growth along one of the polar axes. The absolute direction of preferred growth was determined to be [001] by the pyroelectric measurements. The perfection of the crystal was characterized by synchrotron X-ray topography and optical characterization was made by measuring second harmonic conversion efficiency.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2011.06a
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• pp.76-76
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• 2011

선박이나 산업 플랜트에서 파이프 또는 탱크류의 맞대기 용접 시 안정적인 이면비드의 형성은 매우 중요하다. 대부분의 현장에서 파이프 맞대기 초층용접부의 안정적인 이면비드를 형성하기 위해 3mm의 루트갭을 띄우고 루트면이 없는 V-그루브에서 필러를 사용하는 수동 TIG용접을 주로 사용하고 있다. 수동 TIG용접은 고품질의 비드와 우수한 아크안정성, 그리고 용접인자의 제어가 쉽다는 장점이 있다. 그러나 수동 TIG용접은 용접속도가 10cpm정도로 느리기 때문에 GMAW에 비해 생산성이 낮고 작업자의 숙련도에 따라 품질이 변하게 된다. 본 연구에서는 높은 생산성과 기준갭 1.5mm에서 단차의 허용공차를 크게 하기 위해 루트면 3mm를 가지는 U-그루브의 설계를 하였으며, 두꺼운 루트면을 가지는 그루브에서 안정적인 이면비드를 형성시키기 위해 GMAW에서 아크 충격량에 대한 검토를 실시하였다. GMAW의 아크력이 용입에 어떠한 영향을 미치는지 검토하기 위해 수냉되는 동판에 갭을 1.5mm 띄우고 동일한 용착량과 입열량에서 아크력만을 변화시켜 실험하였다. 또한, U-그루브의 루트부를 모델링하여 두께3t의 평판시편을 각각의 갭과 단차 조건에서 실험하였다. 이 때, 기준갭 1.5mm에서 갭에 의해 생기는 단면적을 기준 갭단면적, 갭이 증가함에 따라 증가되는 단면적을 추가 갭단면적, 갭이 감소함에 따라 감소하는 단면적을 감소 갭단면적으로 정의하였다. 용접 중 발생하는 추가, 감소 갭단면적에 대하여 용착량을 50%의 수준으로 증가, 감소 시켰다. 갭에 따라 아크력을 변경하여 실험을 실시하였고 이면비드의 형상을 확인 하였다. 마지막으로 평판 시편의 조건에서 안정적으로 이면비드가 형성된 조건을 pipe U-그루브에 적용하였다. 그 결과 동판에서 용착량과 입열량이 같음에도 불구하고 아크력이 증가함에 따라 용입이 깊어짐을 확인하였다. 또한. 3t 평판시편에서 아크력의 제어를 통해 큰 단차와 갭이 있을 때, 안정적인 이면비드를 얻을 수 있는 조건을 확립하였다. 마지막으로 pipe U-그루브에서 앞선 실험의 용접조건으로 갭과 단차의 변화에 대해 실험을 하였으나, 시험편의 두께차이에 의한 전도 열손실로 인해 이면비드의 형성이 어려웠고, 아크 충격량의 증가를 통해 이러한 문제를 해결하였다.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.3
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• pp.95-99
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• 2002

3.5KHz subbottom profiling systems are useful for delineating of shallow (up to 10~100m below the sea bottom) geological structure. These systems are generally used to image geological structures with less than 1m of vertical resolution. However swell in the sea is quite often higher than 1m, causing degradation in the quality of the 3.5KHz subbottom profiles. In this paper, we show the quality of digitally recorded data can be enhanced by the suppression of swell effect. Prior to suppression of swell effect, sea bottom detection procedure was applied using the characteristics that the amplitude of sea bottom reflection is high. To suppress the swell effect, we applied moving average method and high-cut filtering method using the extracted water depth of adjacent traces. Acceptable results were obtained from both methods. In the case of bad quality data or shallow data interfered with direct wave, the suppression of swell effect is difficult due to incorrect sea bottom detection.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.7
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• pp.1021-1025
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• 2003

The study was to investigate the quality of wet noodle added with the powder green tea. The wet noodles were prepared to the ratio of 1, 2, 3, 5, 7.5 and 10% (w/w) of the powder green tea based on a flour weight. The initial pasting temperature in an amylograph was increased as the increase of the powder green tea, while peak and final viscosity as the increase decreased. The weight and volume of cooked noodles were decreased, and turbidity of soup was increased with the addition of the powder green tea. L and a values of wet noodles were decreased with the addition of the powder green tea, and b value was increased. Texture profile analysis of cooked noodle showed a increase of hardness, cohesiveness, springiness, chewiness up to 2% powder green tea, but decreased from 3% power green tea. However, adhesiveness decreased as the increase of the powder green tea. From the sensory evaluation, the wet noodles included 1% powder green tea were similarly evaluated as the noodle used whole wheat flour.

• Journal of Korea Society of Industrial Information Systems
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• v.23 no.4
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• pp.107-121
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• 2018

This study investigates the effects of the Kano model on the product quality and quality satisfaction on the FDM low cost 3D printer, which is used by consumer and makers. 3D printer product quality is analyzed in terms of functionality, usability, durability, reliability and safety based on the inherent quality of the product itself. This study were tested using Kano analysis to calculate the product detail characteristics and Timko coefficient to calculate the degree of satisfactory effects of the 3D printer. As a result, this study becomes product size, the output speed, durability against external impact as attractive quality and the safety part is regarded as One-dimensional quality. With the exception of surface resolution, the Timko customer satisfaction index was the same as the Kano model.

• Journal of Global Scholars of Marketing Science
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• v.9
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• pp.189-201
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• 2002

Objectives of this study were: First, the purpose of this study is to develope the factors affecting private brand based on past researches and to review effects of the consumer perception factors affecting private brand preference. Second, to set up research model specifying relationships among price perception, information search and experience, Quality perception and private brand preference. Third, to test hypotheses derived from the research model of this study and to attempts to explain how to have the effect the private brand preference. Marketing implications of this study were: As a result LISREL analysis, price perception, informations search and experience, quality perception increase and enhance private brand preference. Limitations of this study were: Data collection methods used in this study were questionable for the lack of general analysis in the difference of preference between characteristics of purchaser and characteristics of non-purchaser exactly because our sample was only limited to Changwon, Masan and Jinhae. So future study has to include samples in other regions.

• Food Science and Preservation
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• v.13 no.3
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• pp.337-343
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• 2006

This study was conducted to develop naengmyon added with persimmon leaf powder. To find out the proper mixing ratio, physicochemical properties were investigated. There was a little difference in water binding capacity between control and naengmyon added with persimmon leaf powder. Amylogram showed that initial pasting temperature and peak point value were increased as increment of adding amount of persimmon leaf powder. After cooking, the weight of a naengmyon was increased but cooking loss and turbidity were decreased with increment of persimmon leaf powder. At a glance of color difference values, there was a distinctive boundary near at 6%. But similar at over 6% as increasing adding amount of persimon leaf powder texture characteristics such as hardness, adhesiveness, cohesiveness, springness and gumminess were declined. From overall experimental result, the proper mixing ratio of persimmon leaf powder for naengmyon was 4%.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.150-150
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• 2010

질화물 기반의 LED의 경우 c-plane 사파이어에 GaN을 성장 하는 방법이 많이 연구되어 왔다. 그러나 c-plane 위에 성장시킨 LED는 분극현상이 발생하여 양자효율의 저하와 발광파장의 적색 편이를 야기한다[1]. 이런 문제를 해결하기 위하여 a-plane (11-20), m-plane (10-10) 등의 비극성면을 갖는 GaN을 성장을 통해 분극문제를 해결하고자 하는 방법이 제안되었다 [2] 하지만, 현재 비극성 면을 갖는 고품질의 박막을 성장시키기 어렵다는 단점이 존재한다. 고품질의 박막을 성장시키는 방법으로는 ELO와 다중 버퍼층의 사용처럼 여러가지 방법이 연구되고 있다. 하지만 사파이어의 tilt와 열처리에 따른 표면 개질에 대한 연구는 많이 진행되어지고 있지 않다. 본 연구에서는 사파이어에 열처리를 통하여 표면의 특성 변화를 관찰하고 이를 이용하여 고품위 GaN 박막의 품질을 높이려 하였다. r-plane 사파이어에 유기금속화학증착법(MOCVD)을 이용하여 a-plane GaN을 성장하였다. 이 공정에서 사용한 pre-treatment는off-axis angle을 가진 기판의 표면 열처리이다A-plane GaN 성장전에 m-direction으로 off-axis angle을 가진 r-plane 사파이어 기판을 1300도로 가열한 후 각각의 다른 시간에서 열처리를 진행하였다. Off-axis angle을 가진 사파이어는 표면에 step구조를 가지고 있으며, 이 step의 width를 비롯한 표면의 morphology는 off-axis angle에 따라 달라진다. Off-axis angle을 변화시킨 사파이어를 1300도에서 1시간, 3시간, 5시간 annealing하여 표면을 AFM을 사용하여 관측한 결과 step width가 증가하고 step의 형태가 뚜렷해지며 rms-roughness가 변화한 것을 관찰할 수 있었다. 그리고 이 각각의 기판을 동일한 조건으로 a-plane GaN을 성장하여 박막의 특성을 측정하였다. 본 발표에서는 사파이어 기판의 표면 처리에 따른 비극성 GaN의 특성 변화에 대한 분석 결과를 논의할 것이다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.3
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• pp.238-246
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• 1984

The objective of this experiment was to improve the quality of Kochujang and to shorten the aging time of it by using the Kojis of various Aspergillus strains. During the autumn season Kochujangs were mashed with Koji of Aspergillus oryzae, Aspergillus kawachii and Aspergillus shirousamii. Chemical composition of the Kochujang was determined during the aging period. There was no significant difference in quality and component between the Kochujang made with Aspergillus oryzae cultured Koji and Aspergillus kawachii cultured Koji. But the Kochujang with Aspergillus shirousamii cultured Koji was better in flavor, color and amino nitrogen contents than the Kochujang with Aspergillus oryzae cultured Koji, though two Kochuangs were almost the same in general components. The significant difference between the two tested Kochuangs was observed in pH, and the pH of the Kochujong with Aspergillus shirousamii cultured Koji was extremely low during the aging period. Thus it is presumed that Aspergillus shirousamii Koji can be used for the improvement of quality of Kochujang if a suitable method is applied to prevent pH from lowering.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1373-1380
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• 1998

Wet noodles were prepared with wheat flour and mushroom powder (oyster and oak mushrooms), and effects of added mushroom powders on dough rheology and wet noodle quality were examined. Particle size distribution of mushroom powder ranged from 0.04 to $500\;{\mu}m$, which was different from that of wheat flour. The initial pasting temperature in amylograph, and the water absorption and the dough development time in farinograph increased with the increase of mushroom powder. The peak and final viscosities in amylograph, and dough stability in farinograph decreased with the increase of mushroom powder. Decrease of L value and increase of a and b values were shown with the increase of mushroom powder in wheat flour-mushroom powder composite as well as wet noodles. The cooked weight and volume of cooked noodles were decreased, but the turbidity of soup were increased with the addition of mushroom powder. Most of texture parameters (hardness, cohesiveness, chewiness and cutting force) of cooked noodles decreased with the addition of oyster mushroom powder, but increased with the addition of oak mushroom powder. From the result of sensory evaluation, wet noodles containing 3% oyster mushroom powder and 5% oak mushroom powder were rated as high quality wet noodles.