• 한국정밀공학회지
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• 제17권5호
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• pp.180-185
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• 2000

An interface V-notched crack problem can be formulated as a eigenvalue problem. there are the eigenvalues which give stress singularities at the V-notched crack tip. The RWCIM is a method of calculating the eigenvector coefficients associated with eigenvalues for a V-notched crack problem. Obtaining the stress intensity factors for an interface crack in dissimilar materials is examined by the RWCIM. The results of stress intensity factors for an interface crack are compared with those of the displacement extrapolation method by the BEM

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집A
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• pp.115-120
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• 2000

This paper examines that it is possible to apply RWCIM for determining eigenvector coefficients associated with eigenvalues for V-notched cracks in anisotropic dissimilar materials using the complex stress function. To verify the RWCIM algorithm, two tests will be shown. First it is performed to ascertain whether predicted coefficients associated with eigenvectors is obtained exactly. Second, it makes an examination of the state of stress for FEM and RWCIM according to a number of eigenvectors at a location far away from the V-notched crack tip.

• 소음진동
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• 제9권5호
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• pp.943-948
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• 1999

This paper proposes a feasible and effective method for measuring the mechanical-acoustic transfer function by the application of equivalent area and velocity transfer function, a manifestation of the vibro-acoustical reciprocity principle. On the contrary to the volume velocity used in traditional method, the equivalent area is a peculiar raidation characteristics of sound sources and not influenced by any input signal for driving sound source. This invariant property of equivalent area can get rid of boresome works to measure the volume velocity of a sound source every time the driving signal is changed. Moreover, this method has a remarkable advantage to use a general loudspeaker as an accoustic exciter without the assumption of point source and can be applied to all kinds of sound sources even if they are not omni-directional sources.

• 한국자동차공학회논문집
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• 제9권6호
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• pp.178-185
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• 2001

This paper describes the correlation between the interior noise and the trunk wall vibration. Using the vibro-acoustic reciprocity, effect of the trunk wall vibration on the compartment noise is investigated on a medium size car. In the low frequency range, vehicle interior noise is dominated by several acoustic modes of the passenger compartment and the vibration modes of the surrounding shell parts. Especially, vibration of the trunk wall radiates sound and it is transferred through holes on the package tray into the passenger compartment. This paper experimentally reveals that sound can be well produced at some particular vibration modes of the trunk lid and it strongly influences the compartment noise through package tray holes. Contributions of the trunk walls to the interior noise are estimated by measuring the acoustic-structural transfer function, based on the vibro-acoustical reciprocity theorem.

• 대한기계학회논문집A
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• 제25권9호
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• pp.1368-1375
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• 2001

This paper examines that it is possible to apply RWCIM for determining eigenvector coefficients associated with eigenvalues for V-notched cracks in anisotropic dissimilar materials using the complex stress function. To verify the RWCIM algorithm, two tests will be shown. First, it is performed to ascertain whether predicted coefficients associated with eigenvectors are obtained exactly. Second, it makes an examination of the state of stresses for FEM and RWCIM according to a number of eigenvectors at a location far away from the v-notched crack tip.

• 한국해양공학회지
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• 제14권2호
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• pp.36-43
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• 2000

In this paper a Vortex Lattice Method is used to predict the performances of a contra-Rotating Propeller. Greeley and Kerwin's(1982) wake model is adopted instead of the exact trailing vortex geometry. The interaction of the two propellers is treated by the sense that the induction of one propeller upon the other propeller is averaged in the circumferential direction . Two single propellers (DTRC 4119 & DTRC 4842) are chosen and compared with the experimental and other numerical results published. Then the computational results for three CRP's (4-0-4 CRP(DTRC 3686+DTRC 3687A) 4-0-5 CRP(DTRC 3686+DTRC 3849) & DTRC CRT(DTRC 5067+DTRC 5068) are compared with the experimental and numerical results published. The interaction of both propellers by the change of inflow velocity and circulation of each propeller is investigated.

• 석유와에너지
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• 1호통권234호
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• pp.44-49
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• 2003

석유제품은 고율의 세금(특소세 및 교통세) 부과와 소비자나 거래자가 품질ㆍ상표ㆍ계량을 확인하기 어려운 특성을 갖고 있으며, 그 결과 탈세ㆍ무자료 거래 등 불법ㆍ부정유통의 가능성이 매우 크고, 실제로 이 같은 불법ㆍ부정유통이 시장에서 빈번히 발생되고 있다는 지적이 있어왔다. 특히, 1995년이후 석유산업의 전반적인 자유화 및 규제완화 추세에 따라 이동차량을 이용한 무자료 거래와 일부 수입사의 부당영업행위 등 불법ㆍ부정유통의 규모가 커지고 있다는 우려가 제기되어 왔다. 이에 따라 산자부는 2002년 5월이후 연구용역과 관련업계 및 전문가의 광범위한 의견수렴을 거쳐 이번 개선방안을 마련하였다. 2002. 12. 11(수) 규제개혁위원회 경제1분과위원회의 심의를 마쳤으며, 향후 필요한 절차를 거쳐 내년 상반기내 석유사업법령 개정을 추진, 빠른시일내 시행할 예정이다. 산자부는 이번 「석유유통구조 개선방안」과 별도로 『유류구매카드제』 도입을 추진, 정유사ㆍ수입사ㆍ대리점ㆍ주유소ㆍ판매소 및 직매처(대수요처)간의 거래를 카드로 결제하고, 그 내용이 석유공사의 석유수급전산망에 자동입력되게 하여, 석유제품거래의 투명성과 유통의 건전성을 근본적으로 제고할 계획이다.

• 한국사회복지학
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• 제5권
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• pp.41-62
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• 1984

• 원자력산업
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• 제8권12호통권70호
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• pp.22-25
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• 1988

현대사회에서는 대중의 견해를 묻기 위해 자주 여론조사를 실시한다. 그러나 여론조사는 주어지는 질문과 방법에 따라 나타나는 결과는 매우 상반되게 나타난다. 미국 에너지계발협의회(USCEA)의 Ann S. Bisconti 부이사장은 본고에서 여론조사의 위험성과 나타난 결과에 대해서 정확한 판단을 지적하고 있다.

• 월간산업보건
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• 통권252호
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• pp.39-52
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• 2009