• Journal of Radiation Protection and Research
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• 제18권1호
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• pp.1-7
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• 1993

국제방사선방어위원회(ICRP)는 최근의 권고 60(1990)에서 이전의 권고 26(1976)에는 없었던 새로운 용어들을 도입하였다. 이중에서도 동 위원회는 지금까지 사용되어 왔던 국제 방사선단위 및 측정위원회(ICRU) 개념의 '션량당량(dose equivalent)'을 대체하는 용어로 '등가선량(equivalent dose)'을 새로 정의하여 방사선방어 프로그램에의 적용을 권고하고 있다. 그러나 한편 동 위원회는 선량 당량이라는 용어도 여전히 채택하고 있기 때문에 경우에 따라 두 양의 사용시 불필요한 혼동을 불러일으킬 수가 있다. 따라서 본 해설문에서는 방사선 방어, 관리 및 측정분야 종사자들의 이해를 돕기 위하여 두 양의 정의와 사용상의 차이점에 대하여 정리하였다.

• KSBB Journal
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• 제29권1호
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• pp.42-49
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• 2014

The aim of this study was to develop a composite human skin equivalent for wound healing. Collagen type1 and acellular dermal matrix powder were utilized as the scaffold with dermal fibroblasts and keratinocytes for the development of a composite human skin equivalent. Fibroblast maintained the volume of composite skin equivalent and also induced keratinocytes to attach and proliferate on the surface of composite skin equivalent. The composite human skin equivalent had a structure and curvature similar to those of real skin. Balb-C nu/nu mice were used for the evaluation of full-thickness wound healing effect of the composite human skin equivalent. Graft of composite skin equivalent on full-thickness wound promoted re-epithelialization and granulation tissue formation at 9 days. Given the average wound-healing time (14 days), the wound in the developed composite skin equivalent healed quickly. The overall results indicated that this three-dimensional composite human skin equivalent can be used to effectively enhance wound healing.

• 한국식품과학회지
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• 제22권5호
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• pp.575-581
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• 1990

일정한 열처리 공정에 대해 Equivalent point가 존재함을 이상적인 두가지의 직접가열곡선 즉, $120^{\circ}C$에서 10분간 $135^{\circ}C$에서 10초간의 등온가열 곡선을 이용하여 예시하였다. 이러한 조건하에서 Arrhe nius model을 적용한 경우 임의의 Ea-값을 사용하여 G-값을 결정하고 Bigelow model을 적용한 경우, 임의의 z-값을 사용하여 F-값을 결정하였다. 이들 값을 사용하여 Equivalent time과 Equivalent Temperature를 두가지 방법 즉, 직교좌표법과 회기분석법에 의해 결정하였다. 이들 두 방법에 의해 결정된 Equivalent Point는 서로 일치하였으며 각각의 값은 초기에 가정했던 직접가열곡선의 가열시간 및 온도와 일치하였다.

• 치과방사선
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• 제27권1호
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• pp.87-97
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• 1997

The purpose of this study was to evaluate the method for quantitative assessment of bone mass from aluminum-equivalent value of hydroxyapatite by using digital imaging system consisted of Power Macintosh 7200/120, 15-inch color monitor, and GT-9000 scanner with transparency unit. After aluminum-equivalent image made from correlation between aluminum thickness and grey scale, the accuracy of conversion to mass from aluminum-equivalent value was evaluated. Measured bone mass was compared with converted bone mass from aluminum-equivalent value of hydroxyapatite block by correlation formula between aluminum-equivalent value of hydroxyapatite block and hydroxyapatite mass. The results of this study were as follow; 1. Correlation between aluminum thickness and grey level for obtaining aluminum-equivalent image was high positively associated(r²=0.99). Converted masses from aluminum-equivalent value were very similar to measured masses. There was, statistically, no significant difference(P<0.05) between them 2. Correlation between hydroxyapatite aluminum-equivalent and hydroxyapatite mass was shown to linear relation (r²=0.95). 3. Converted masses from aluminum-equivalent value of 3 dry mandible segments were similar to measured masses. The difference between the exposure directions was not significantly different(P<0.05).

• 대한기계학회논문집B
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• 제35권9호
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• pp.897-902
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• 2011

PEMFC 의 내부에서 발생하는 화학반응은 계면의 물리적 조건 및 물성에 지배되고 그 거동은 임피던스로 표현된다. 일반적으로 임피던스 특성은 전기적 등가회로로 표현이 가능하기 때문에 PEMFC의 임피던스 계측 결과를 등가회로를 이용하여 해석함으로써 간단히 성능 진단을 할 수 있을 것이다. 본 연구에서는 이러한 등가회로를 이용하여 고분자 전해질 연료전지의 특성평가에 관한 기초연구를 수행하였다. 교류 임피던스 계측 값과 다양한 등가회로(단순 등가회로, CPE 를 고려한 등가회로, 2 개의 시정수를 고려한 등가회로, 2 개의 CPE 를 고려한 등가회로)를 이용하여 특성평가를 수행하였다. 그 결과 등가회로를 이용한 PEMFC 의 특성평가가 가능하고, 2 개의 CPE 를 고려한 등가회로가 가장 정도가 높음을 확인하였다.

• 호남수학학술지
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• 제4권1호
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• pp.167-172
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• 1982

Let A be a Banach $^{\ast}$-algebra and C(t) be a closed $^{\ast}$-subalgebra of A gengerated by $t{\in}A$. A is locally $B^{\ast}$-equivalent [$B^{\ast}$-equivalent] if C(t) [A] for every hermitian element t is $^{\ast}$-isomorphic to some $B^{\ast}$-algebra. It was proved that the locally $B^{\ast}$-equivalent algebras with some conditions is $B^{\ast}$-equivalent by B. A. Barnes. In this paper, we obtain the some conditions for a locally $B^{\ast}$-equivalent algebra to be $B^{\ast}$-equivalent.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.1218-1223
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• 2007

In this study, we experimentally investigate the equivalent ring theory for a slightly asymmetric ring. The slightly asymmetric ring has mode pair and frequency pair due to the small asymmetry and this mode pair generates beat in vibration and sound. In this paper, a slightly asymmetric ring is modeled as the equivalent ring, i.e., the assemblage of a symmetric ring and imperfect point masses. The equivalent ring has the same mode pair condition as that of the original asymmetric ring. Effect of the additional mass attachment is investigated by the equivalent ring theory and the result is compared with those of the measurement and the finite element analysis. It is confirmed that the original ring and the equivalent ring show the same change in frequency and mode under the various additional imperfection mass conditions. The equivalent ring theory explains how the asymmetric elements influence the mode characteristics and provides useful information to tune the beat property.

• 전기학회논문지
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• 제62권7호
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• pp.937-942
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• 2013

Equivalent series impedance of high-voltage pulsed power capacitor is one of the important electrical characteristics both for users and for capacitor manufacturers because it may have serious effects on the performance of pulse forming circuits. In this paper, definition of equivalent series impedance and factors which generate equivalent series impedance are reviewed. Theoretical analysis for the calculation of equivalent series impedance based on differential measurement method is described and calculation program has been developed. In order to acquire data which are necessary to calculate equivalent series impedance from discharging current waveform, charging-dischargig controller has been manufactured. Measurement results of equivalent series impedance for high voltage pulsed power capacitor have been given.

• 대한전기학회논문지:전력기술부문A
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• 제52권12호
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• pp.684-690
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• 2003

This paper estimates line constants of equivalent five-conductors model using the reduced equivalent method. Actually, the catenary system is considered by the equivalent five-conductors model in the electrical aspect. Therefore, we should compose the catenary system of the equivalent five-conductors model, then the line constants of this equivalent five-conductors model are calculated. This paper shows the reducing process about the real system of the field by using the proposed theory. Also the line constants of reduced system are provided in this paper.

• Structural Engineering and Mechanics
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• 제39권5호
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• pp.661-667
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• 2011

In the famous equivalent elasticity modulus method proposed by Ernst for the geometrical nonlinear analysis of stay cables, the cable shape was assumed as a parabolic curve, and only a part of the gravity load normal to the chord was taken into account with the other part of gravity load parallel to the chord being ignored. Using the actual catenary curve and considering the entire gravity load of stay cables, the present study has derived the equivalent stiffness method to analyze the sag effect of stay cables in cable-stayed bridges. The derived equivalent stiffness can be degenerated into Ernst's equivalent elasticity modulus method with some approximations. Therefore, the Ernst's method is a special and approximate formulation of the present method. The derived equivalent stiffness provides a theoretical explanation for the famous Ernst's formula.