• Title/Summary/Keyword: 진구도

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Analysis of the Effects of Out-of-Sphericity in Spiral Grooved Hemispherical Air dynamic Bearings (나선 홈을 가진 반구형 공기 동압베어링에서 진구도 오차의 영향 해석)

  • Choe, U-Cheon;Sin, Yong-Ho;Choe, Jeong-Hwan
    • Journal of the Korean Society for Precision Engineering
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    • v.17 no.9
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    • pp.145-150
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    • 2000
  • Out-of-sphericity is degree of deformation of an air bearing sphere deviated from a perfect sphere. This paper investigates numerically the effect of out-of-sphericity error on the radial stiffness of an air bearing Three types of out-of-sphericity modes are considered. in this study the stiffness is calculated from pressure distribution at the bearing surface which is obtained by solving th Reynolds equation. in some cases large out-of-sphericity errors are found to improve the stiffnesses of air bearings. This implies that an air bearing of perfect hemispheres is not necessarily of the best performance. Thus much labor and cost in manufacturing air bearings can be saved, In addition the radial stiffness of an air bearing depends greatly on the application direction.

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An Analysis on the Educational Needs of the Career Education according to the Career Recognition of the Undergraduates (대학생의 진로인식에 따른 진로 교육 요구도 차이 분석)

  • Kim, Hyun-Soon;Kim, Ji-Hyo
    • The Journal of the Korea Contents Association
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    • v.16 no.5
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    • pp.651-659
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    • 2016
  • The purposes of this study is to investigate the influence of career recognition upon career development competencies and educational needs. To achieve this, the survey was carried out and 362 undergraduates participated. The findings of the survey were shown as follows: First, the students perceived that career management was needed the most, and then came career information searches. Next, career transition technologies, positive self-concept formation, career planning, and effective interpersonal relationships were in order. Second, the influence of career recognition upon the level of the preparations showed statistically significant differences, however, the influence of career recognition upon the level of the requirement did not reveal statistically significant differences. Third, the rating of the educational needs was identical from the first place to the third, but different from the fourth to the sixth. These results will contribute to enhancing the efficiency of career education.

시베리아횡단철도(TSR) 이용 활성화와 한-러 경제 협력

  • 권원순
    • Journal of the Korean Society for Railway
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    • v.4 no.1
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    • pp.40-56
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    • 2001
  • 지난해 6.15 남북공동선언을 계기로 남북간의 교류와 협력의 분위기가 조성되고 남북정상회담의 가시적 성과의 하나로 이산가족상봉과 남북철도 연결사업이 시작되어 경의선의 남쪽구간은 상당한 공사진척도를 보이고 있다. 그러나 최근의 상황은 북쪽은 아직 공사조차 시작하지 않고 있는 입장이다. 그러나 이와는 별도로 남북철도의 연결과 이의 대륙철도와의 연결은 '철의 실크로드' 구성과 함께 시베리아횡단철도(TSR)의 이용이 그간의 논의 수준을 넘어 구체화 되었다. 게다가 수교이후 러시아가 가장 적극적으로 접근하고 있는 시베리아횡단철도(TSR)의 활성화 논의는 남북관계가 한러관계 나아가 남·북·러 삼각협력의 복잡한 구도 속에서 논의되고 있는 현실이다. (중략)

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Development of Mirror~like Polishing System for Hemispherical High-¬speed Precision Bearing for Digital VTR Drum (디지탈 VTR 드럼용 반구 고속 정밀베어링의 경면연마 시스템)

  • 김정두;최민석;우기명;김영일
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.04a
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    • pp.24-28
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    • 1996
  • Mirror-like polishing system of hemisphericall high-speed precision bearing for digital VTR drum was developed. Mechamism of the polishing process was analyzed in the view point of polishing contact range and contact length between the tool and the workpiece surface. It was suggested that the two stage polishing process adoptiong the diamond grinding wheel and polishing tool instead of multistage lapping processes, which enables the mass production of the bearing by reduction of polishing time.

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Ultra Precision Polishing Mechanism of Glass Ball in Float Polishing (액중 부상 방식에 의한 유리볼의 초정밀 연마 기구)

  • 김한섭;박규열
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2000.05a
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    • pp.850-853
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    • 2000
  • 최근에 초정밀 제조업 분야에서 볼의 이용에 관한 연구가 급속히 진행되고 있으며, 일부 반도체 분야에서는 BGA(Ball Grid Array)와 같은 용도로 이용되기도 하며, 볼 자체를 반도체 칩으로 응용하려는 시도가 제안되어 있다. 이러한 적용분야들에서 볼의 진구도, 정밀도 및 청정도 등을 만족시킬 수 있는 가공기술이 선결되어야 한다. 본 연구에서는 초정밀 볼의 가공기술 개발을 목적으로 하여 유리 볼을 대상으로 하고 $H_2O$와 CeO$_2$를 혼합한 연마재를 사용하여 부상회전에 의한 비접촉식 연마방법을 제안하고 가공특성을 조사하였다 연구 결과로서, 비 접촉식 볼의 가공에서는 가공에 앞서 $H_2O$와의 전처리 과정을 거침으로 해서 가공속도를 촉진시킬 수 있다는 사실이 확인되었다.

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Comparative Study of Labor-Saving Structure in Various Sowing Methods of Winter Barley (대맥의 파종진식별 생력화 구조 비교연구)

  • 민경수;구자옥;김인권
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.26 no.4
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    • pp.311-317
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    • 1981
  • As the low labor-productivity is being floated up to be the most limiting factor in barley cropping, the endeavor of many researchers concerned have been concentrated on recovering from that. For this reason, in this experiment 8 kinds of sowing methods were employed to survey the yield productivity and the labor-requirement of each methods. And with promising the possibility of consistent mechanization, both prediction of the assurable requirement of labor investment and calculation of the labor productivity in each method were estimated so that the possibility of labor-saving in barley cultivation investigated. Also sowing methods for labor-saving cultivation were presented according to the labor-structure of farm as divided with the phases.

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From the competitive communication service market which is about MVNO wholesale price-based research (경쟁적인 통신서비스 시장에서 MVNO 도매대가콘텐츠에 관한 연구)

  • Bae, Khee-Su;Song, Yeong-Hwa;Jeong, Do-Jin;Jeon, Heung-Joo
    • Proceedings of the Korea Contents Association Conference
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    • 2011.05a
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    • pp.127-128
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    • 2011
  • 기존에는 통신시장에 진출하려면 막대한 설비투자와 사업권의 획득이 필요했으나 이제는 망을 비롯한 주요 설비 없이도 사업을 할 수 있는 기회가 열렸다. 이러한 통신사업에 대한 신규진출 규제완화 움직임은 이동통신시장 경쟁구도의 변화뿐만 아니라 통신 산업 전반에 큰 영향을 미칠 것으로 기대되고 있다. 본 연구는 정부의 재판매(MVNO)제도의 도입과 관련하여 합리적인 도매대가 산정방안에 대한 고찰을 목적으로 다음과 같은 결론을 도출하였다. COST PLUS 모형과 RETAIL MINUS 모형에 각각 영업이익률과 원가 대비이익률을 적용하여 도매대가를 산출한 결과 원가대비이익률을 적용하여 RETAIL MINUS 모형으로 산출했을 때 가장 높은 도매대가가 산출되었다. 반면 도매대가가 가장 작은 모형은 영업이익률 적용 RETAIL MINUS 모형으로 나타났다. 이러한 결과는 도매대가산정 시 비용의 구분과 이익률의 산정이 중요한 요소로 작용하였으며, 이를 통해 보다 정교한 MVNO 도매대가산정을 할 수 있을 것으로 기대된다.

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Needs for Consumer Information on Internet (인터넷소비자정보요구도에 관한 연구)

  • 이수진;이승신
    • Journal of the Korean Home Economics Association
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    • v.39 no.12
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    • pp.159-175
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    • 2001
  • The internet which is only opened for special class at the past, diffuse to all classes like junior.senior highschool and woman in general and it boost the internet's popularize. So the consumers can reduce the all physical.time cost, and now the internet settle in the most important method to find the informations. I hope this project can expect the protection the over-carrying of consumer information on internet and consumers can activity acquire the information in consumer's side. Also in the business's side, it promote the developing of fair information offers for lighten the inequality of information. And in the governments side, it's a basic information to plan the legal system for help the consumers to use the safe and correctness internet.

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Improvements of Field Safety Management Using Image Processing (영상처리를 활용한 현장 안전관리 개선방안)

  • Jang, Min-Woo;Lee, Min-Yong;Gu, Do-Jin;Shin, Dong-Ho;Kang, Woo-chul
    • Proceedings of the Korea Information Processing Society Conference
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    • 2019.10a
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    • pp.710-712
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    • 2019
  • 오늘 날 산업현장에서는 현장에서의 생산성 향상과 안전을 강화하기 위한 방법으로 IT기술을 접목한 현장 안전관리 분야가 비약적으로 성장하고 있다. 특히 제조업, 건설업 분야의 산업현장에서 발생하는 안전사고에 대응하기 위해 현장 관리자를 보조하는 IT 기술은 지속적인 분석과 개선이 요구된다. 본 논문에서는 산업현장에 투입되는 근로자의 안전을 위하여 인물 Tracking과 광학문자인식 기법을 활용하여 스마트 현장 안전관리 시스템의 구조와 개선방안을 제시한다.

Passion + Innovation + Marketing = A Successful New Market Development 『A Case of Pulmuone Fresh Ramen, 'Jayeonun Masitda'』 (열정 + 혁신 + 마케팅 = 신시장 창출 『풀무원 '자연은 맛있다'의 생라면 시장 개척 사례』)

  • Chu, Kyounghee;Lee, Doo-Hee;Park, Seong Yeon;Yoo, Shijin
    • Asia Marketing Journal
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    • v.13 no.3
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    • pp.233-248
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    • 2011
  • This case illustrates a story of passionate and innovative new market development by Pulmuone, a fresh food provider in Korea. The company has been successfully developing a new market by introducing a (non-frying) fresh ramen, 'Jayeonun Masitda - The Nature Is Tasty' in the packaged ramen market dominated by fried ones. In this case, a detailed new market development process by Pulmuone will be investigated including; company overview, a new product development process, marketing strategy formulation, marketing mix implementation, market performance, and future directions. Pulmuone has been making efforts to create a new product category by marketing non-frying ramens since 1995, but with a modest success. In 2011, Pulmuone finally succeeded to develop an innovative product, 'Jayeonun Masitda' that brought more health and nutrition conscious consumers' attention in the ramen market. The company intended to change the current competitive structure in the ramen market, i.e., from the strength of taste and the amount of ingredient to fried/non-fried and the freshness of ingredient. By this new positioning, Pulmuone aimed to reshaping the ramen market into competition between healthy and unhealthy ramens. Pulmuone has been successful in developing a new market. Sales revenue of 'Jayeonun Masitda' has been continuously increasing, and customers are found to be highly satisfied with the product resulting in a high repeat purchase rate. The company's successful new market development can be attributed to a faithful new product development process, innovative technology, an appropriate positioning strategy, and consistent marketing communication. In addition, Pulmuone's eco-friendly corporate image and the organization's passion to grow are also important factors for success of this new market development.

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