• 정보화사회
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• s.9
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• pp.8-9
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• 1988

• 정보화사회
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• s.14
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• pp.18-19
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• 1989

• Journal of Korean Elementary Science Education
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• v.41 no.2
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• pp.236-249
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• 2022

This study analyzed the contents of science education at the elementary school level in Joseon as narrated by teacher Yun Jae-Cheon (尹在千) during the Japanese colonial period. The study added commentaries and criticisms about his articles. Yun Jae-Cheon was born toward the end of the Korean Empire and gained first-hand experience of the Japanese colonial period and liberation. He was a teacher at Kyeongseong Normal School (京城師範學校) during the Japanese colonial period and published several articles related to science education in an educational journal called The Educational Study of Joseon (<朝鮮の敎育硏究>). Notably, he wrote "Science Education in Joseon" (朝鮮の理科敎育) in 1939, which analyzed and reported the overall science education at that time. This study outlined the context of science education in Joseon through the eyes of the Korean teacher during the Japanese colonial period. In Joseon, under the Japanese colonial rule, Yun Jae-Cheon's view of science education was extremely limited as he could not help to reveal the pro-Japanese activities.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2005.11a
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• pp.356-358
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• 2005

• The Research Journal of the Costume Culture
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• v.17 no.1
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• pp.177-188
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• 2009

SCM as the important marketing strategy enhance the firm's efficiency and compatibility in global market environment such as global outsourcing. Firms adopted SCM realized the need to evaluate precisely the performance of SCM. In spite of importance of SCM, there was not much intention and research to measure SCM performance in textile fashion industry. Therefore, the purpose of this case study was to measure performance of supply chain management in textile fashion business using BSC(Balanced Score Card) to measure not only financial perspective but also non-financial perspectives such as customer perspective, internal business perspectives, financial perspective, and innovation & learning perspective. The questionnaire developed by the reviews of the literature was adopted for this study. The results of this study showed that SCM performance was enhanced from the point of customer perspective(cost, quality, time, service), financial perspective(cash cycle time, inventory turn over, inventory obsolescence, return on asset, return on investment, capacity utilization), and innovation & learning perspective(cost for human resource management, service for human resources). But there was same performance level regarding internal business perspective(lead time, cost for manufacturing process, product quality control, productive flexibility for time, quantity, and variety). Therefore, we should keep close relationship and two way communication among supply chain members to promote better SCM performance.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1998.04a
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• pp.69-76
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• 1998

A precision wear tester is developed to measure the wear rate of a high friction and high pressurized cylinder. The tester consists of indentor system and optical measuring system. The indentor system has two diamond indentors so that they make indents on the inside of the cylinder by using compressed air system. The X-Y-$\theta$ stage of the measuring system can trace the positions of the indents and can measure the diameters of them. The variation of the diameter of each indent after test is converted into the wear rate.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.277-280
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• 2009

Mechanism of combustion frequencies occurring during combustion is experimentally investigated in model combustor with V-gutter flameholder. this combustor has a long duct shape with a cross section area of $40{\times}40\;mm$. The v-gutter type flameholder with 14mm width is mounted at the bottom of combustor. Kerosene and methane were used as fuel, and these fuel were injected transversely into air crossflow. It is found that combustion frequencies were considered as 1L longitudinal mode caused by combustor geometry and vortex shedding mode of flameholder. And fuel phase effect and nozzle effect were also observed in the low frequency range.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.107-110
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• 2009

Combustion oscillations are caused by a coupling between acoustic waves and unsteady heat release. They can be eliminated using passive controller such as a helmholtz resonator. But, helmholtz resonator is normally only effective over a narrow frequency range. In this work, helmholtz resonator is applied for reducing the combustion oscillations and we vary the helmholtz resonator volume using piston in oder to tune in the wide range of operating conditions. As the result, it is found that the dominant combustion oscillations can be reduced by optimizing the size of resonator volume. Also, from these results, we investigate feasibility of actively tuned passive control

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.11a
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• pp.447-448
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• 2008

The goal of this study is to find flame dynamic behavior using a transverse fuel injection in a model combustor, and is to investigate main causes of unstable combustion in a liquid-fueled combustor. For transverse fuel injection into air cross flow, spray result shows similar tendency with Wu et al.[1998] until spray arrives at flame-holder. However, passing through flame-holder, fuel inflow into recirculation region of flameholder is not sufficient so it makes large difference between shear flame and recirculation flame behind flameholder. In combustion tests, the stable flame shows a kind of shear flames and low peaks of dynamic pressure frequencies. On the other hand, unstable flame shows periodic detached flame in recirculation zone and a strong peak of dynamic pressure frequency. The instability frequency is highly affected by influx air velocity, air temperature, equivalence ratio and wake or vortex shedding frequency behind the flameholder.

• Korean Journal of Poultry Science
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• v.27 no.1
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• pp.37-41
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• 2000

This study was carried out to examine the effects of Lactobacillus spp. on performance and cecal microflora in broiler chicks. Eight diets consisting of basal diet(C), C+Lactobacillus crispatus BC7 (T2), C+Lactobacillus reuteri BC9 (T3), C+L.reuteri BC5+L.crispatus BC9 (T4), C+L. reuteri BC5 (T1)+L.reuteri BC9 (T5), C+L.crispatus BC7+L.reuteri BC9 (T6) and C+L.reuteri BC5+L.crispatus BC7+L.reuteri BC9 (T7), were fed to Ross male broiler chicks for 5 weeks. The level of supplemented Lactobacillus spp. was 107 cfu/g diet. Body weight and feed intake were measured every week, and cecal microfla was counted at 1 and 5 weeks for Lactobacillus and yeast. Body weight increased signigicantly in supplemental Lactobacillus treatments from 2 weeks of age (p<0.05). Chicks in T2, T5 and T5 of treatments were heavier than those of other treatments at 5 weeks of age(p<0.05). Viability was not different significantly. Feed intake and feed conversion also were not different, although feed conversion improved slightly in supplemental Lactobacillus treatments. Lactobacillus spp. of cecal content was increased in supplemental Lactobacillus treatments at 1 week, but no significance was found. The number of yeast in cecum was not different from that of supplemental Lactobacillus. In conclusion, Lactobacillus, L.crispatus BC7 and L.reuteri BC9 from broiler cecum could contribute to the increase in body weight with supplemented mono-or mixing of di-lactobacilli. The results indicate that Lactobacillus feeding can benefit to intestinal lactobacillus at early growing broiler.