• Bulletin of the Korean Chemical Society
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• 제19권1호
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• pp.93-98
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• 1998

The molecular geometries and harmonic vibrational frequencies of biphenyl in the ground and the first excited triplet states have been calculated using the Hartree-Fock and Becke-3-Lee-Yang-Parr (B3LYP) density functional methods with 6-31G* basis set. Structural change occurs from a twisted benzene-like to a planar quinone-like form upon the excitation to the first excited state. Scaled harmonic vibrational frequencies for the ground state obtained from the B3LYP calculation show good agreement with the available experimental data. A few vibrational fundamentals for both states are newly assigned based on the B3LYP results.

• Bulletin of the Korean Chemical Society
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• 제19권1호
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• pp.103-106
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• 1998

The oxidation product bis(2-oxo-3H-1,3,4-thiadiazolidinyl)-5,5-disulfide (5b) was obtained from an attempted synthesis of 5-thioxo-3H,4H-1,3,4-thiadiazolidin-2-one (1). Spectroscopic results indicate that the most stable tautomeric form of 1 is the lactam-thiol form (1b). The computed total energies and relative energies at the MP4 level also showed that the most stable tautomer is 1b.

• 한국전자통신학회논문지
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• 제12권3호
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• pp.445-450
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• 2017

본 논문에서는 CPW 선로를 기반으로 한 수직 결합 구조를 이용한 반전력의 방향성 결합기가 설계 및 제작되었다. CPW 수직 결합 구조의 우수 모드는 유전체 기판 두께의 반을 갖는 일반적인 CPW 선로로 해석될 수 있으며, 기수 모드는 CBCPW 선로로 해석될 수 있다. 반전력 방향성 결합기는 유전율 2.55, 기판 두께 0.76mm의 테프론 기판 상에 중심주파수 2.45 GHz, 대역폭 61.6%로 설계되었으며, 제작된 반전력 방향성 결합기는 중심주파수 2.45 GHz, 대역폭 66.1%를 가졌고, 중심주파수에서 반사손실과 격리도는 각각 19.52 dB와 19.47 dB를 가졌다.

• 한국정보통신학회논문지
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• 제4권4호
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• pp.825-834
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• 2000

본 논문에서는 비아-홀 접지를 고려한 K-대역 인터디지트 대역통과필터를 설계하였다. 중심 주파수가 19.6GHz에서 25~30%대역만을 통과시키기 위해 6차 인터디지트 대역통과 필터를 마이크로 스트립라인으로 구성하였으며 비아-흘의 수에 따른 필터의 특성을 분석하였다. 비아-흘 접지와 인터디지트 대역통과필터는 설계 최적화 과정을 통하여 통과대역에서 중심주파수와 대역폭관계를 만족시킬 수 있었으며 실제 제작후 측정결과 중심주파수는 19.150Hz 삽입손실은 -4.IdB, 반사계수는 -16.7dB로 비아-홀 접지의 영향을 고려한 설계가 이루어짐을 증명하였다.

• 농촌의학ㆍ지역보건
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• 제47권2호
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• pp.99-108
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• 2022

본 연구는 19세 이상 성인들을 대상으로 B형간염 백신 접종률, 백신 접종이유 및 미접종 이유, 백신 접종 관련 요인을 파악하고자 하였다. B형간염 백신 접종률은 사후가중치를 적용 후 1차 38.0%, 2차 32.5%, 3차 26.9%로 나타났다. B형간염 백신 접종 관련 요인으로는 여자가, 저연령에서, 군부 거주자가, 직업이 있을 때, 고학력자가, 건강보험 가입자가, 배우자가 있을 때, 동거가족이 있을 때, 국가 권고 성인 예방접종을 인지하고 있을 때, 의사에게 성인 예방접종의 필요성을 설명 받은 경험이 있을 때, 본인의 성인 예방접종 기록 보관하고 있을 때, 성인 예방접종이 감염병 예방에 도움이 된다고 높게 인지하고 있을 때, 국가나 지방자치단체의 성인 예방접종 홍보 경험이 없을 때에 백신 접종률이 높게 나타났다. 결론적으로 우리나라 성인의 B형간염 백신 접종률은 양적 향상 및 질적인 측면에서의 개선을 위한 국가 정책 마련이 필요함을 발견하였다. 또한 성인의 B형간염 항체 형성률을 함께 파악하여 감염병 발생 감소나 퇴치를 위해서 국가수준의 예방접종률 목표치 선정과 함께 달성 정도 평가를 위한 정기적인 성인 예방접종률 산출이 필요하다. 더욱이 국가의 예방접종통합관리시스템을 통하여 안정적으로 성인의 예방접종 기록을 관리할 수 있도록 전산등록률 향상 방안을 마련할 필요가 있다.

• 핵의학기술
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• 제28권1호
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• pp.81-87
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• 2024

Purpose: CA 19-9 is the most widely used tumor marker for the diagnosis of digestive system tumor, especially pancreatic and biliary tract cancer. This study was conducted to improve the result value near reference range by comparing the reagents of CA 19-9 one step method and two step method. In addition, it was intended to establish a standard for selecting reagents. Material and Methods: 120 patients who visited the National Cancer Center in 2023 were selected as subjects for this study. The reagents used in the study were CA 19-9 IRMA kits (Shinjin, Korea) and three types of reagents were compared. Two step method reagent that is currently being used (A), one step method reagent (B) and two step method reagent improved by request (C) were compared and regression analysis was performed on their data. And we also performed recovery test, linearity test and hook effect test for each reagent. Result: There were 46 cases of reagent B in which the concentration value was lower than the result measured in reagent A that was previously used, and 77 cases of reagent C. As a result of regression analysis of reagents A, B, and C, the coefficients of determination of reagents A and B, reagents A and C, and reagents B and C were 0.653, 0.577, and 0.875. In the recovery rate test and the linearity test, the results of all reagents were good, and in the hook effect test, reagent B showed a hook effect at a low value. Conclusion: The improved reagent C appears to have been improved based on the concentration value of reagent B, which the manufacturer judged to be more stable at low concentrations. The hook effect in reagent B can be a fatal reason for disqualification when selecting reagents in general patient samples which high-concentration samples appear frequently. The first improved reagent C will be able to be used once it is confirmed that it has more stability for various concentration values.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제19권2호
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• pp.137-145
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• 2012

While investigating the Lauricella's list of 14 complete second-order hypergeometric series in three variables, Srivastava noticed the existence of three additional complete triple hypergeometric series of the second order, which were denoted by $H_A$, $H_B$ and $H_C$. Each of these three triple hypergeometric functions $H_A$, $H_B$ and $H_C$ has been investigated extensively in many different ways including, for example, in the problem of finding their integral representations of one kind or the other. Here, in this paper, we aim at presenting further integral representations for the Srivatava's triple hypergeometric function $H_B$.

• 한국통신학회논문지
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• 제22권1호
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• pp.72-80
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• 1997

알루미나 기판에 PHEMT 칩을 이용하여 750MHz CATV 증폭모듈을 설계 및 제작하였다. 와이어 본딩된 PHEMT 칩을 이용하여 개발된 2단 푸쉬풀 증폭기는 50~750MHz 대역에서 19dB 이득, 15dB 이상의 입출력 반사손실 4.2dB 이하의 잡음지수 특성을 나타내었다. 이 결과는 상용의 750MHz 증폭기모듈의 특성보다 우수하다. 본 논문에서는 증폭기 설계, 회로 구성 및 측정 결과 등을 제시하였다.

• Steel and Composite Structures
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• 제19권6호
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• pp.1483-1499
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• 2015

With the improvement of the quality of construction materials and the development of construction technologies, large-scale long-span steel frame buildings have been built recently. The P.E.B system using tapered members is being employed as an economically-efficient long-span structure owing to its advantage of being able to distribute stress appropriately depending on the size of sectional areas of members. However, in December 2005 and in February 2014, P.E.B buildings collapsed due to sudden loads such as snow loads and wind gusts. In this study, the design and construction of the P.E.B system in Korea were analyzed and its structural safety was evaluated using the finite element analysis program to suggest how to improve the P.E.B system in order to promote the efficient and rational application of the system.

• Steel and Composite Structures
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• 제19권3호
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• pp.777-787
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• 2015

Production and properties of metal matrix composites reinforced with an in-situ high aspect ratio $AlB_2$ flake have been investigated. Boron 2.2wt.% was dissolved in pure Al and Al-Cu alloy at $1300^{\circ}C$ by adding directly boron oxide which resulted in 4 vol.% reinforcing phase. The in-situ $AlB_2$ flake concentration was increased up to 30 vol.% in order to increase the tensile strength of the composites. Hardness, compressive strength and tensile strength of the composite were measured and compared with their matrix. Results showed that 30 vol.% $AlB_2/Al$ composite show a 193% increase in the compressive strength and a 322% increase in compressive yield strength. Results also showed that ductility of composites decreases with adding $AlB_2$ reinforcements.