• 제목/요약/키워드: D factor

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층간분리성장률(dAD/da)과 섬유가교효과인자(FBE)를 이용한 Al/GFRP 적층재의 피로거동 해석 (The Analysis of Fatigue Behavior Using the Delamination Growth Rate(dAD/da) and Fiber Bridging Effect Factor(FBE) in Al/GERP Laminates)

  • 송삼홍;김철웅
    • 대한기계학회논문집A
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    • 제27권2호
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    • pp.317-326
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    • 2003
  • The influence of cyclic bending moment on the delamination and the fatigue crack propagation behavior in Al/GFRP laminate such as the wing section was investigated. The main objective of this study was to evaluate the relationship between crack profile and delamination behavior. And a propose parameter on the delamination growth rate(d $A_{D}$/da) of Al/GFRP laminates with a saw-cut using relationship between delamination area( $A_{D}$) and cycles(N), crack length(a), stress intensity factor range($\Delta$K). Also, the fiber bridging effect factor( $F_{BE}$ ) was propose that the fiber bridging modification factor($\beta$$_{fb}$ ) to evaluate using the delamination growth rate(d $A_{D}$/da). The shape and size of the delamination zone formed along the fatigue crack between aluminum alloy sheet. Class fiber-adhesive layer were measured by an ultrasonic C-scan image. The shape of delamination zone turns out to be semi-elliptic with the contour decreased non-linearly toward the crack tip. It represents that relationship between crack length and delamination growth rate(d $A_{D}$/da) were interdependent by reciprocal action, therefore it's applicable present a model for the delamination growth rate(dA/sib D//da) in Al/GFRP laminates.minates.s.

LOCALLY SEMICOMPLETE DIGRAPHS WITH A FACTOR COMPOSED OF k CYCLES

  • Gould, Ronald J.;Guo, Yubao
    • 대한수학회지
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    • 제41권5호
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    • pp.895-912
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    • 2004
  • A digraph is locally semicomplete if for every vertex $\chi$, the set of in-neighbors as well as the set of out-neighbors of $\chi$ induce semicomplete digraphs. Let D be a k-connected locally semicomplete digraph with k $\geq$ 3 and g denote the length of a longest induced cycle of D. It is shown that if D has at least 7(k-1)g vertices, then D has a factor composed of k cycles; furthermore, if D is semicomplete and with at least 5k + 1 vertices, then D has a factor composed of k cycles and one of the cycles is of length at most 5. Our results generalize those of [3] for tournaments to locally semicomplete digraphs.

색채조화가 전채요리의 음식선택속성에 미치는 영향 (The Effect of Food Color on Hors d′oeuvre Choice Characters)

  • 김장익;고범석
    • 한국조리학회지
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    • 제8권2호
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    • pp.153-171
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    • 2002
  • This study had three major purpose: 1) to examine the relationship between coloring factor of Hors d'oeuvre and preference of dishes. 2) to examine the relationship between coloring factor of Hors d'oeuvre and selection of dishes. 3) to examine the relationship between coloring factor of Hors d'oeuvre and customer satisfaction. Questionnaires for the study were distributed 300 subjects in deluxe class hotels in Seoul. Among 300 questionnaires, 280 subjects were collected and utilized for analysis. In HY hotel, 35 subjects of customers, 24 subjects of cooks, and 32 subjects of service personnels were collected. In R hotel, 29 subjects of customers, 32 subjects of cooks, and 32 subjects of service personnels were collected. In H hotel, 29 subjects of customers, 34 subjects of cooks, and 33 subjects of service personnels were collected. Analysis ways used for this study were frequency analysis, factor analysis, reliability analysis, ANOVA, To accomplished the objective 1), ANOVA was utilized. To accomplished the objective 2) and 3), regression analysis was unitized. The findings from this study were as follows. First it was found that selection of dishes was affected by coloring factory of Hors d'oeuvre. Secondly, it was found that customer satisfaction was affected by coloring factor of Hors d'oeuvre. Consequently, development of Hors d'oeuvre by harmonizing of various colorings should be activated to raise level of preference of dishes. Also, in regard to level of satisfaction, harmony of various colorings should be required.

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Partial Sequence of the Bovine (Bos taurus coreanae) Myogenic Factor Encoding Gene MyoD

  • Kim, H.S.;Park, E.W.;Yoon, D.H.;Kim, H.B.;Cheong, I.C.;Cho, B.W.;Im, K.S.
    • Asian-Australasian Journal of Animal Sciences
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    • 제12권5호
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    • pp.689-694
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    • 1999
  • This experiment was carried out to isolate the partial bovine (Bos Taurus coreanae) myogenic factor encoding gene, MyoD, using the rat myogenic factor (MyoD) gene sequence and to compare the gene sequence between another myogenic factor (Myf 5) and MyoD gene of the bovine. To make the probe and isolate the MyoD gene, PCR was performed to amplify rat and bovine MyoD gene including exon I, II and intron I. The homology between mouse and bovine MyoD is high; bovine MyoD gene shows 17 different gene sequence region compared to rat MyoD. Among those, two regions have significant differences; one is the exon I part between 2834 and 2850 bp, the other is intron part between 3274 and 3303 bp of the mouse. At this region homology was 40% in the former and 50% in the latter. Homology between bovine MyoD and Myf5 was 83% in the exon 1. Especially exon I in the Myf5 602-617 bp and 651-683 bp have significant differences. These results suggest that MyoD gene have a similar gene structure in mouse and bovine and MyoD and Myf5 of the bovine, at least in part, have a similar expression and activity.

Effects of Technology and Innovation Management and Total Factor Productivity on the Economic Growth of China

  • LEE, Jung Wan;XUAN, Ye
    • The Journal of Asian Finance, Economics and Business
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    • 제6권2호
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    • pp.63-73
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    • 2019
  • The paper aims to investigate relationships between technology and innovation management, total factor productivity and economic growth in China. By comparing the trends in total factor productivity growth of industrialized economies (i.e. OECD), this study intends to showcase the importance of total factor productivity progress in the Chinese economy. The study employs time series data of an annual basis for the period from 1977 to 2016 retrieved from the World Development Indicator. The study employs unit root test, cointegration test, fully modified least squares estimation method, canonical cointegrating regression and dynamic least squares estimation method to test the hypotheses. The results of the cointegrating regression analysis show that manufacturing growth leads to an increase of total factor productivity in the short-run in China. The findings of the study suggest that manufacturing (i.e. technology and product innovation) is positively related to the increase of total factor productivity in the short-run and total output growth in the long-run. The findings suggest that promoting technology and innovation management and supporting R&D subsidies may reduce the marginal cost of conducting R&D and increase the rate of technology and innovation management and R&D activity and therefore, the total factor productivity growth rate.

강도감소법에 의한 3차원 사면안정해석에 대한 매개변수 연구 (Parametric Studies of Slope stability Analysis by 3D FEM Using Strength Reduction Method)

  • 김영민
    • 한국지반신소재학회논문집
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    • 제15권4호
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    • pp.25-32
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    • 2016
  • 지반공학에서 평면변형율을 가정하는 2차원 사면안정해석은 일반적으로 널리 사용되고 있다. 이 가정은 사면활동이 넓은 영역에 걸쳐서 발생되는 가정이므로 3차원 효과가 무시된다. 대다수 연구에서 2차원해석의 최소안전율값은 3차원해석에 비하여 작게 평가되는 보수적인 결과를 나타낸다. 최근에는 컴퓨터의 소프트웨어와 하드웨어를 포함한 해석방법의 발달로 3차원해석에 대한 요구가 커지고 있다. 본 논문에서는 원호모드, 병진모드사면을 이용하여 유한요소에 의한 2, 3차원해석 및 2차원 한계평형해석을 통하여 수치해석을 실시하였다. 해석결과 매개변수(요소망크기, 체적팽창각(dilatency angle), 경계조건, 응력이력, 모델차원)에 따른 사면안정해석에 미치는 영향을 분석하였다. 해석결과 2차원 해석보다 3차원 해석에 의한 사면의 안전율 값은 항상 크게 평가되며, W 뱡향 경계조건이 롤러지지인 경우, 사면폭에 의한 결과 차이는 없는 것으로 조사되었다.

국가연구개발사업의 과학적 성과분석을 위한 새로운 계량지표 개발에 관한 연구 (Developing Bibliometric Indicators for Analysis & Evaluation of National R&D Programs)

  • 허정은;김해도;조영돈;조석민;조순로
    • 기술혁신학회지
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    • 제11권3호
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    • pp.376-399
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    • 2008
  • 최근 연구개발 투자규모가 급속히 증가함에 따라 정부는 R&D사업의 투자효율성을 높이기 위한 다양한 정책을 구사하고 있다. 구체적으로 R&D사업에 대한 성과평가를 강화하고 평가결과를 예산의 조정 및 배분에 반영하는 등 성과중심의 평가체계를 정착시키기 위해 노력하고 있다. 이처럼 국가연구개발사업에 대한 평가가 성과중심으로 체계화되기 위해서는 R&D 성과물을 과학적 객관적으로 분석할 수 있는 성과지표의 개발이 필요하다. 이에 본 연구에서는 전 부처 연구개발사업에 공통으로 적용할 수 있는 성과지표인 SCI논문지표를 바탕으로 교육과학기술부 3대 연구개발사업에 대한 구체적인 사례분석을 실시하여 이들 사업이 우리나라 전체 R&D에서 차지하는 질적 양적 위상을 파악하고자 하였다. 이러한 분석을 위해 SCI 관련 기존지표와 더불어 4개의 신규지표를 소개하였고 신규지표들의 타당성 조사를 위해 모의실험을 실시하였다. 그 결과 보완된 순위보정영향력지수(ordinal rank normalized impact factor, omIF)가 분야간 비교 시 가장 적절한 성과지표인 것으로 분석되었다.

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반도체 레이저의 변조특성에서 비선형 이득에 관한 연구 (Analysis of nonlinear gain in modulation characteristics of semiconductor lasers)

  • 엄진섭;김창봉
    • 전자공학회논문지D
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    • 제35D권2호
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    • pp.93-100
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    • 1998
  • In this paper we analyze the effect of nonlinear gain on laser modulation characteristics applying a small-signal analysis to the rate equation which includes a nonlinear gain term. Also we analyze the resonance frequency and the damping factor which determine laser modulation characteristics, define K factor which is the proportionality factor between resonance frequency and damping factor, and conclude that the decrease in K factor is due to increases in differential gain and no correlation between K factor and nonlinear gain is identified.

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LFFD 및 SFFD를 이용한 3차원 라스트 데이터 생성시스템 개발 (Three Dimensional Last Data Generation System Design Utilizing SFFD and LFFD)

  • 김시경;박인덕
    • 제어로봇시스템학회논문지
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    • 제12권2호
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    • pp.113-118
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    • 2006
  • A new last design approach based on the Limb line FFD (LFFD) and Scale factor FFD (SFFD) is presented in this paper. The proposed last design method utilizes the dynamic trimmed parametric patches for the measured foot 3D data and last 3D data. Furthermore, the proposed last data generation system utilizes cross sectional data extracted obtained from the measured 3D foot data. First, the last design rule of the LFFD is constructed on the FFD lattice based on foot last shape analysis. Secondly, SFFD is constructed on the LFFD new lattice based on scale factor deformation. The scale factor is constructed on the boundary edges of polygonized patch and the cross section last data boundary edge of the polygon object. Suppose the two boundary curves have been preprocessed so that they run in the same direction and they forms the SF(Scale Factor). In addition, the control points of FFD lattice are derived with cross. sectional data interpolation methods from a finite set of 3D foot data.

정부 R&D 지원사업의 참여요인이 중소기업의 R&D 성과에 미치는 영향 (The Effect of Government R&D Subsidies Program Participation Factor for SMEs R&D Performances)

  • 최승욱;정진택;유연우
    • 디지털융복합연구
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    • 제12권5호
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    • pp.171-180
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    • 2014
  • 본 연구는 정부의 R&D 지원사업에 참여하는 중소기업들의 참여요인이 기업의 R&D성과에 미치는 영향에 관한 것이다. 현재 정부의 R&D 지원사업은 여러 형태로 운영되고 있으며, 각 기업에 보조금이나 설비 및 장치, 인력, 교육 등의 지원이 이루어지고 있다. 각 기업들 또한 다양한 사업 참여요인을 가지고 지원 사업에 참여하게 된다. 따라서 본 연구는 이와 같은 정부 R&D 지원사업의 사업수행 종료 후, 기업의 다양한 참여요인이 관리적 성과에 해당하는 사업관리능력에 긍정적인 영향을 미치는지 대한 가설을 검증한다. 또한, 사업관리능력이 기술적 성과인 R&D 투자 강화와 기술역량 강화에 영향을 미치는지에 대한 가설을 검증한다. 이 분석결과를 통해 향후 정부지원사업에 참여하는 여러 기업들의 전략적 R&D성과 관리를 위한 방향설정에 도움이 될 것이다.