• 제목/요약/키워드: Gyongsan

검색결과 18건 처리시간 0.022초

Interfacial Crack Propagation Under Various Mode-Mixes

  • Park, Byung-Sun;Chai, Young-Suck
    • Journal of Mechanical Science and Technology
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    • 제16권1호
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    • pp.39-45
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    • 2002
  • Initiation and propagation of interfacial crack along bimaterial interface are considered in this study. A biaxial loading device for a single specimen is used for obtaining a wide range of mode-mixities. The specimen is an edge-cracked bimaterial strip of glass and epoxy; the biaxial loading device, being capable of controlling displacements in two perpendicular directions, is developed. A series of interfacial crack initiation and Propagation experiments are conducted using the biaxial loading device for various mixed modes. Normal crack opening displacement (NCOD) is measured near crack front by a crack opening interferometry and used for extracting fracture parameters. From mixed mode interfacial crack initiation experiments, large increase in toughness with shear components is observed. The behavior of interfacial crack propagation analyzed as a function of mode-mix shows that initial crack propagation is delayed with increase of mode-mixity, and its velocity is increased with positive mode-mixity but decreased with negative case. However, it is found that crack propagation is less accelerated with positive mode-mixity than the negative mode-mixity, which may be caused by contact and/or effects of friction between far field and near-tip Held along the interfacial crack.

ON THE RATIO X/(X + Y) FOR WEIBULL AND LEVY DISTRIBUTIONS

  • ALI M. MASOOM;NADARAJAH SARALEES;WOO JUNGSOO
    • Journal of the Korean Statistical Society
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    • 제34권1호
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    • pp.11-20
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    • 2005
  • The distributional properties of R = X/(X + Y) and related estimation procedures are derived when X and Y are independent and identically distributed according to the Weibull or Levy distribution. The work is of interest in biological and physical sciences, econometrics, engineering and ranking and selection.

Fuzzy Logic Modeling and Control for Drilling of Composite Laminates ; Simulation

  • Chung, Byeong-Mook;Ye Sheng;Masayoshi Tomizuka
    • International Journal of Precision Engineering and Manufacturing
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    • 제2권1호
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    • pp.11-17
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    • 2001
  • In drilling of composite laminates, it is important to minimize of reduce occurrences of delaminations. In particular, a peel -up delamination at entrance and push-up delamination at exit are common. Deleaminations may by avoided by regulating the drill thrust force can be controlled by adjusting the feedrate of the drill. Dynamics involved in drilling of composite laminates is time varying and nonlinear. In this paper, a fuzzy logic model and control strategy are proposed. Simulation results show that the fuzzy model can describe the nonlinear time-varying process well. The fuzzy controller realizes a fast rise time and a little overshoot of drilling force.

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Polyester/면 혼방직물의 alkali 처리가공 (Alkali-Treatment of Polyester/Cotton Blend Fabric)

  • Lee, Suk-Young;Cho, Hwan
    • 한국염색가공학회지
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    • 제3권3호
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    • pp.6-14
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    • 1991
  • To develop an one-bath process for weight-reduction and mercerization of polyester/cotton fabric, concentrated NaOH solution was padded and steam-treated at high temperature. Following results which can be used commercially are obtained. (1) Steaming temperature of 110-12$0^{\circ}C$ is most efficient. (2) Optimum concentration of NaOH solution is 15-20%. (3) Most favorable weight-reduction is 20% in the aspect of fabric handle, and under this treating condition, dye exhaustion onto the mercerized cotton fiber is also increased to 40% or more. From above results, we believe that the economical and concurrent weight-reduction and mercerzation of polyester/cotton fabric can be realized. Moreover, with continuous treatment by pad-steam procedure, it is expected that this is, also, advantageous for the improvement of fabric quality and productivity.

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ON THE BERWALD'S NEARLY KAEHLERIAN FINSLER MANIFOLD

  • Park, Hong-Suh;Lee, Hyo-Tae
    • 대한수학회논문집
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    • 제9권3호
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    • pp.649-658
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    • 1994
  • The notion of the almost Hermitian Finsler manifold admitting an almost complex structure $f^i_j(x)$ was, for the first time, introduced by G. B. Rizza [8]. It is known that the almost Hermitian Finsler manifold (or a Rizza manifold) has been studied by Y. Ichijyo [2] and H. Hukui [1]. In those papers, the almost Hermitian Finsler manifold which the h-covariant derivative of the almost complex structure $f^i_j(x)$ with respect to the Cartan's Finsler connection vanishes was defined as the Kaehlerian Finsler manifold. The nearly Kaehlerian Finsler manifold was defined and studied by the former of authors [7]. The present paper is the continued study of above paper.

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지리정보체계를 이용한 일반폐기물 매립후보지의 입지선정에 관한 연구 (A Study on Selection of Proposed Waste Facilities Sites using Geographic Information System)

  • 배민기;장병문
    • 한국지리정보학회지
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    • 제1권2호
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    • pp.14-25
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    • 1998
  • 본 연구는 일반폐기물 매립지의 입지인자들의 상대적 중요도에 입각하여 매립후보지를 선정함으로서 합리적인 폐기물 매립지의 입지선정의 이론적, 실천적 토대를 제공하는 것을 목적으로 한다. 일반폐기물의 입지인자 및 그 입지 기준의 선정은 기존문헌의 고찰을 통해 이루어졌으며, 입지인자들간의 상대적 중요도 평가는 비율적 층화추출방법으로 선정된 전문가집단을 대상으로 한 계층분석방법(Analytic Hierarchy Process : AHP)을 적용하였다. 사례지역은 심각한 매립지의 부족과 평탄한 지형적 특성으로 인하여 입지선정에 어려움을 겪고 있는 경상북도 경산시를 대상으로 하였다. IDRISI V2.002를 사용하여 하나의 지리정보체계를 구축하고 경사, 토양, 인구 등 17개의 주제도면을 생성하였으며, 토지적합성분석은 선형조합법과 요소조합법을 동시에 적용하여 두 방법이 가진 방법상의 문제점을 보완하여 합리적인 일반폐기물 매립후보지 선정의 이론적, 실천적 바탕을 제시하였다.

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지역 급식소 성격에 따른 이용 노인의 영양소 섭취수준 및 급식 만족도 비교 : 유료 및 무료 급식 (Comparison of Nutrient Intake and Meal Service Satisfaction of Elderly at the Local Community Centers : Free and Reduced Meal Service Charge)

  • 최봉순;권선영;서주영;이인숙;이희자
    • 대한지역사회영양학회지
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    • 제10권3호
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    • pp.303-310
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    • 2005
  • The purpose of this study was to compare the nutrient intake and foodservice satisfaction of homebound elderly had lunch at the local community centers by the difference of meal service charge. Two local community center with cons-regate meal service program located in Daegu and Gyongsan were selected; one with free of meal service charge (F), and the other with 500-1,000 won for meal service charge (K), According to the dietary assessment, energy and nutrient intakes of the 156 elderly subjects were as a whole under the Korean Recommended Dietary Allowance (RDA). Elderly or F service conte. showed higher $\%$ RDA for the selected nutrients and MAR (mean adequacy ratio) than those of K service center (p<0.001). Participants were satisfied with most of the congregation meal service from community conte. with different reasons such as 'tasty (K service center)' and 'free of charge (F service center)'. In conclusion, elderly had the lunch at the community center with free of meal service charge was poor nutrition status and lower socioeconomic level than the other type of community center in this area. Therefore, healthy menu for elderly should be developed and managed by professional dietitian, as well as its impact on health status of this group, and congregate meal service system might be extended to the homebound elderly of whole community with free of charge.

작업공간 활용증대를 위한 컴퓨터 데스크 디자인 연구 -유형별 개발사례를 중심으로 - (Computer Desks Design for More Workspace Enlargement - Especially on the Case Study of Their Typical Development -)

  • 박규현
    • 디자인학연구
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    • 제14권3호
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    • pp.27-36
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    • 2001
  • 중.소기업의 장점은 대기업이 할 수 없는 틈새시장의 공략이다. 대기업이 디자인 개발을 거대조직 안에서 비교적 긴 시간을 요구하며 체계적으로 이행해 나갈 동안 중.소기업은 수익성이 발견되는 아이템에 대하여 매우 발빠르게 이를 추진하고 전략을 세워 비교적 찬은 기간에 제한된 범위의 시장점유 계획을 추진해 나갈 수 있다. 컴퓨터 데스크는 사용자의 사용환경과 목적의 변화에 따라 그때그때 얼마든지 대기업이 하기 어려운 중.소기업 특유의 전략제품이라 할 수 있다. 본 고는 국가적 생산주체로 최근 중.소기업 활성화를 위한 지역특성화 추진계획에 힘입어 지방의 한 가구생산업체에 대한 $\ulcorner$99년도 산학혈동연구개발사업$\lrcorner$ 지원의 개발과정과 그 결과물에 대한 보고서라 할 수 있다. 작업공간 팔용 증대를 위한 컨셉 내용을 유형별로 제시하면서 과연 어떠한 것이 중.소기업 특유의 전략상품으로 적절한 것인지를 파악해 보았다. 컨셉의 내용과 특징에 따라 5가지의 유형을 제시하였으며 그 가운데(키보드 전.후 슬라이드(Slide) 형>이 소비자 요구와 생산성, 적가성(適價性), 에너지 절약성, 사용성 둥의 제 조건을 충족시킬 수 있는 것으로 판단되어 작업공간 팔용 증대를 위한 컴퓨터 데스크로서 적합함을 결론지을 수 있었다.

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