• Title/Summary/Keyword: cut-outs

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P-Version 유한요소법

  • 우광성
    • Computational Structural Engineering
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    • v.2 no.4
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    • pp.15-20
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    • 1989
  • 이글에서는 2가지 예제를 통해 h-version과 p-version의 비교를 살펴보면서 p-version 해석이 h-version에 비해 상대적으로 많은 장점들을 가지고 있으며, 신뢰도, 정확도, 효율성, 경제성, 용장성 등 측면에서 우월함을 증명해 보였다. 특히 응력집중(stress concentration)이 일어나는 crack-tips, cut-outs, reentrant corners, presence of stiffners, mixed boundary conditions 등 많은 특이성(singularity) 문제에 더욱 적합함을 본 예제 외의 발표된 많은 논문들을 통해 알 수 있으며, 모델링의 단순성에 기인하여 사용이 매우 쉽다는 것도 무엇보다 큰 이점이라 하겠다. p-version은 h-version의 비효율성을 차수 p를 1, 2 또는 3으로 줄인 후 이 값을 고정시키고 다시 요소분할을 통해 진해(true solution)에 접근시키는 방식을 위하면 다시 종래의 h-version으로 환원되는 호환성을 갖고 있다는 것이다. 고로 구조해석에서 h-p version이 가장 이상적인 유한요소해석 방법이라 할 수 있겠는데, 다시 말하면 균열문제의 경우 균열선단(crack-tip)에서는 p-level을 높이고 (p=8, 9 or 10) 비교적 응력집중이 낮은 영역에서는 p-level을 낮춤으로써 (p=3, 4 or 5) 그 효율성을 극대화할 수 있겠다.

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A Study of the on-Line Surface Roughness Monitoring using the Cutting Force in Face Milling Operation (정면밀링작업에서 절삭력을 이용한 On-Line 표면조도 감시에 관한 연구)

  • Baek, Dae Kyun;Ko, Tae Jo;Kim, Hee Sool
    • Journal of the Korean Society for Precision Engineering
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    • v.14 no.1
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    • pp.185-193
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    • 1997
  • This paper presents the on-line monitoring of the surface roughness in a face milling operation. The cut- ting force was used to monitor the surface roughness, since the insert run-outs not only deteriorate surface roughness but also change cutting force. AR model and band energy method were taken to extract the fea- tures from the cutting force. The features extracted from AR modelling are more accurate about the moni- toring than those from band energy method, whereas, the computing speed of the former is slow. An artifi- cal neural network discriminated the level of the surface roughness by using the features extracted via signal processing.

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Transformation of Cooperative Groups for Agricultural Production with the Change Agricultural Productive Force (농업생산력의 변화에 따른 농업생산조직의 발전과정)

  • Joe, Soung-Back;Choi, Min-Ho
    • Journal of Agricultural Extension & Community Development
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    • v.3 no.1
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    • pp.1-16
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    • 1996
  • The purpose of this study was to interpret the transformation of Cooperative Groups for Agricultural Production(CGAP) with the change of the Agricultural Productive Force. The specific objectives were; 1) To investigate the change of agricultural labour-power, 2) To investigate the change of agricultural mechanization and arable land, 3) To interpret the transformation and content of CLAP. The population of farmhouseholds has decreased continuously since the late 1960s. Especially, with the move-outs of youth ages of twenties to forties, the condition of agricultural labour-power has been more serious. The processing of agricultural mechanization was a small scale step in the 1970s, but after the 1980s there was a spread of middle-large machines. However the usage rate of agricultural machines was constrained by the bad conditions of arable land. From the 1970s to now, the CGAP have bean processed by many kinds of patterns. In the 1970s, the lack of labour-power caused the creation of the Co-Working Team. After the late of 1970s, the wage of agricultural employees was raised, because the working population of agriculture was cut down. Also, the induction of agricultural machine was promoted. As a result, in the 1980s, the Machine-Using Team occurred due to these conditions of agricultural productive force. In the late of 1980s, the population decreased more rapidly, and the use of large machines were spread. Than farmhouseholds laking labour-power gave a trust to other farmhouseholds and Teams which had machines. In 1990, Given-Trust Cooperations were enacted by law, and in order to overcome the lack of labour-power, and solve the problem of the successors of agriculture, Cooperative Organizations were also enacted by law. Finally, in Korea from the 1970s to now, as the agricultural productive force has barn changed, the Co-Working Team was transformed into the Machine-Using Team, and the Machine-Using Team was transformed into the Given-Trust Cooperation, and the Cooperative Organization.

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A Study on the Costume Designs of Arts in the Italian & Russian Avant-Garde - Focused on Futurism and Constructivism - (이탈리아와 러시아 전위(Avant-Garde) 예술의상 디자인 연구 - 미래주의(Futurism)와 구성주의(Constructivism)를 중심으로 -)

  • Park, Yoon-Jeong
    • The Research Journal of the Costume Culture
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    • v.19 no.1
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    • pp.128-149
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    • 2011
  • This study dealing with the Italian futurist and Russian constructivist costume designs which aimed for new fashion design freed from the conventional meanings of fashion and explore the artistic purpose reflected within the designs expressed differently according to cultural and regional differences in order examine the early 20th century Avant-grade costume designs. The scope of this study is limited to the 1910s to the 1930s when the Italian futurism and the Russian constructivism were originated and were most active. This monograph focused on the works of the Italian futurists, Giacomo Balla who declared the 'Manifesto delle moda minile futurista', Fortunato Depero, and Thayaht who suggested a new direction for the futurist, and on the works of the Russian constructivists Alexander Rodchenko, Varvara Stepanova and Liubov Popova. As an one method of investigated, this paper is used materials of various sources to examine their features. Futurists costume designs expressed a radical conception of progress and their source of aesthetics was dynamism. The concept of 'power' which was the basis of the futurists was incorporated in the costumes while non-symmetrical cut-outs and bright and vivid colors completed the futurist costume designs. Moreover the Russian constructivists brought advances in the field of fabric and textile designs. What was particularly interesting about the Russian constructivist costumes was that the artists worked at the textile mills themselves, directly involved in the designs and manufacturing of fabric, developing an advancement in textile and a new understanding of costume. Furthermore, many Russian artists settled in Paris, actively participating in the fashion industry, and therefore, they have greatly contributed to the development of the early 20th century Avant-garde costume designs.