• 정보화사회
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• 통권9호
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• pp.8-9
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• 1988

• 정보화사회
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• 통권14호
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• pp.18-19
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• 1989

• 한국초등과학교육학회지:초등과학교육
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• 제41권2호
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• pp.236-249
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• 2022

이 연구는 일제강점기의 교사 윤재천(尹在千)이 언급한 조선의 초등 과학교육에 대한 내용을 분석한 것이다. 윤재천은 대한제국 말에 태어나 일제강점기와 광복을 직접 경험한 사람이었다. 일제강점기에 경성사범학교 교사였던 윤재천은 <조선의 교육 연구(朝鮮の敎育硏究)>라는 교육 전문 잡지에 과학교육에 관련된 글을 많이 게재했다. 특히 그가 1939년에 저술한 "조선의 이과교육(朝鮮の理科敎育)"은 조선인 교사가 평가한 당시의 과학교육 전반을 분석하여 보고한 기사였다. 이 연구에서는 일제강점기에 조선인 교사의 눈으로 본 조선의 과학교육의 전반적인 상황을 추적했다. 일제가 강제 점령한 식민지 상황의 조선에서 윤재천이 생각했던 과학교육의 관점은 친일적인 색채를 드러내지 않을 수 없었던 한계가 있었다.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2005년도 추계학술대회 논문집
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• pp.356-358
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• 2005

• 복식문화연구
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• 제17권1호
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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.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1998년도 제27회 춘계학술대회
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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.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2009년도 춘계학술대회 논문집
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• pp.277-280
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• 2009

본 연구는 v-gutter형 보염기를 장착한 연소기 내에 발생한 연소 주파수의 발생 메커니즘에 대해 규명 하는 것이다. 연소기는 $40{\times}40\;mm$의 단면적을 가진 긴 덕트 형상을 가지고 있으며, 14mm의 폭을 가진 v-gutter 형의 보염기를 장착하였다. 연료로 등유와 메탄를 수직 분무하여 실험을 수행하였다. 연소 시 발생하는 주파수는 연소기의 형상에 기인한 1L 종방향 모드와 보염기에서 발생하는 와류 주파수가 주로 발생함을 확인하였다. 또한 연료의 특성에 기인한 주파수와 노즐의 영향에 대한 주파수가 저주파 영역에서 발생함을 확인하였다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2009년도 춘계학술대회 논문집
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• pp.107-110
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• 2009

연소불안정현상은 주로 음향파와 열방출률 섭동간의 상호작용에 의해 발생한다고 알려져 있다. 이러한 현상은 헬름홀츠 공진기와 같은 수동제어기를 사용하여 감소시킬 수 있다. 그러나 헬름홀츠 공진기는 일반적으로 좁은 주파수대역에 대해서만 효과가 있는 단점을 가진다. 따라서 본 연구에서는 다양한 작동 범위에서 효과를 가질 수 있도록 피스톤을 사용하여 헬름홀츠 공진기의 부피를 변화시켜가며 연소불안정현상에 적용하였다. 그 결과 피스톤을 최적위치에 동조시킴으로써 연소 불안정 모드의 진폭을 감소시킬 수 있었다. 또한 이러한 결과를 바탕으로 능동적으로 동조되는 수동제어방식의 가능성에 대해서 알아보고자 한다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년도 제31회 추계학술대회논문집
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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.

• 한국가금학회지
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• 제27권1호
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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.