• Steel and Composite Structures
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• 제45권1호
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• pp.83-100
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• 2022

Timber is one of the few natural, renewable building materials and glulam is a type of engineering wood product. In the present work, timber-based braces are applied for retrofitting midrise Special Moment Resisting Frame (SMRF) using two types of timber base braces (Timber base glulam, and hybrid Timber-Steel-BRB) as alternatives for retrofitting by traditional steel bracings. The improving effects of adding the bracings to the SMRF on seismic characteristics of the frame are evaluated using load-bearing capacity, energy dissipation, and story drifts of the frame. For evaluating the retrofitting effects on the seismic performance of SMRF, a five-story SMRF is considered unretofitted and retrofitted with steel-hollow structural section (HSS) brace, Glued Laminated Timber (Glulam) brace, and hybrid Timber-Steel BRB. Using OpenSees structural analyzer, the performance are investigated under pushover, cyclic, and incremental loading. Results showed that steel-HSS, timber base Glulam, and hybrid timber-steel BRB braces have more significant roles in energy dissipation, increasing stiffness, changing capacity curves, reducing inter-story drifts, and reducing the weight of the frames, compared by steel bracing. Results showed that Hybrid BRB counteract the negative post-yield stiffness, so their use is more beneficial on buildings where P-Delta effects are more critical. It is found that the repair costs of the buildings with hybrid BRB will be less due to lower residual drifts. As a result, timber steel-BRB has the best energy dissipation and seismic performance due to symmetrical and stable hysteresis curves of buckling restrained braces that can experience the same capacities in tension and compression.

• 미생물학회지
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• 제41권3호
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• pp.157-163
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• 2005

요각류 Paracyclopina nana Acetate Kinase를 클로닝하였다. 전체 open reading frame은 1,200 bp이었으며, poly(A) signal sequence가 ORF에 내재되어 있었다. 분자계통학적 분석결과 P. nana acetate kinase 유전자는 진핵생물계 곰팡이류인 Aspegillus와 같은 branch를 형성하였고, P. nana acetate kinase가 다른 원핵미생물들의 acetate kinase와는 구별되며 fungi와 같은 branch에 존재하는 것을 확인하였다. 또한, E. coli를 이용하여 원핵세포 발현벡터를 이용한 단백질 발현 유도를 통하여 P. nana acetate kinase 단백질 분자량이 약 50 kDa에 이르는 것을 확인하였다. 이 자료는 본 요각류와 다른 생물의 acetate kinase 단백질의 생화학적 특성비교에 유용하게 쓰이리라 사료된다.

• Journal of Microbiology and Biotechnology
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• 제1권1호
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• pp.22-30
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• 1991

In order to secrete the Bacillus subtilis cytidine deaminase (CDase, cytidine/2'-deoxycytidine deaminase) encoded by the B. subtilis cdd gene in E. coli by the aid of signal sequences, the cdd gene was fused in-frame to either amyE or penP signal sequences and the gene expression and CDase localization were examined. For the penP signal sequence::cdd fusion, the cdd gene with 9 amino acids truncated from the 5'-terminus was fused in-frame to the signal sequence, then the $cdd^{+}$ colonies were not occurred from the minimal plate by cdd complementation. The result suggests that 9 amino acids on the $NH_2-terminal$ of CDase have an essential function in the enzyme activity. The hybrid protein obtained by fused gene amyE signal sequence::cdd structural gene gave $cdd^{+}$ phenotype and about half of the total CDase activity was found to be secreted in the periplasm of E. coli transformant JF611/pSO202. The periplasmic CDase activity of JF611 harboring pSO52 containing the intact cdd gene was considerablely lower than that of the cells harboring pSO202 carrying the hybrid cdd gene. This suggests that the CDase was secreted to the periplasm through the cytoplasmic membrane by the aid of the amyE signal sequence in the E. coli transformant.

• 한국안광학회지
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• 제20권1호
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• pp.9-14
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• 2015

목적: 본 논문에서는 안경테가 땀에 노출되었을 때 나타나는 변화를 알아보았다. 방법: 양백, 모넬 및 티타늄 재질의 안경테를 pH 6.5, 6.0, 5.0의 인공땀에 1주, 3주, 6주 동안 노출시킨 후 표면, 경도, 인장강도의 변화를 알아보았다. 결과: 인공땀에 의해 양백, 모넬, 티타늄 재질 안경테 표면의 부식이 유발되었으며 부식 양상은 각 재질별로 상이하였다. 인공땀의 pH와 노출시간에 비례하여 3가지 재질의 안경테 모두 경도가 감소하였으나 인장강도는 변화가 없었다. 결론: 인공땀에 의해 안경테의 표면 부식과 경도 변화가 관찰되었으므로 안경테의 일상적인 관리가 필요함을 제안한다.

• 대한토목학회논문집
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• 제33권2호
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• pp.409-422
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• 2013

부재간의 연결조건에 따른 다양하고 복잡한 강구조물의 P-${\Delta}$ 해석 및 좌굴 거동특성을 파악하기 위하여, 본 연구에서는 부재의 연결이 회전 및 이동스프링으로 구성된 부분강절(semi-rigid) 뼈대요소의 일반화된 접선강도 행렬을 유도하였고 이로부터 다시 Taylor 전개를 적용하여 탄성강도 행렬과 기하학적 강도행렬을 일반화된 형태로 제시하였다. 이를 위하여, 보-기둥부재의 좌굴조건을 만족시키는 처짐함수로부터 안정함수(stability function)를 유도하였고, 횡변위(sway)를 고려한 힘-변위관계와 적합조건을 고려하여 엄밀한 부분강절 뼈대요소의 접선강도행렬을 제시하였다. 다양한 수치해석 예제에 대해 타 연구자의 해석 결과 및 본 연구의 선형 및 비선형 해석이론을 통한 좌굴해석 결과를 비교하여 본 연구의 타당성과 부분강절 뼈대구조물의 좌굴거동 특성을 제시하였다.

• 대한간호학회지
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• 제48권2호
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• pp.221-231
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• 2018

Purpose: This study aimed to compare the effects of three interventions on pain, blood pressure, and pulse rate during infiltration anesthesia in patients about to undergo gamma knife surgeries. Methods: The three interventions employed in a university-affiliated Hospital in J City, South Korea were as follows: EMLA cream plus Vapocoolant spray (Vapocoolant, n=30), EMLA cream plus 10.0% Lidocaine spray (Lidocaine, n=30), and EMLA cream only (EMLA, n=30). The equivalent control-group pre test - post test study design was used. Pain was assessed subjectively using the numeric rating scale (NRS) and objectively using a Galvanic Skin Response (GSR) tester. NRS scores were assessed after infiltration anesthesia and the GSR was assessed during infiltration anesthesia. Blood pressure and pulse rate were assessed twice: before and after infiltration anesthesia. Data were collected between August 3, 2016 and March 24, 2017. Results: NRS scores after infiltration anesthesia and the GSR during infiltration anesthesia were significantly lower in the Vapocoolant group than in the Lidocaine and EMLA groups (F=13.56, p<.001 and F=14.43, p<.001, respectively). The increase in systolic blood pressure (F=4.77, p=.011) and in pulse rates (F=4.78, p=.011) before and after infiltration anesthesia were significantly smaller in the Vapocoolant group than in the Lidocaine and EMLA groups; however, no significant differences were observed in diastolic blood pressures (F=1.51, p=.227). Conclusion: EMLA cream plus Vapocoolant spray was the most effective intervention to relieve pain and to lower increase in systolic blood pressure and pulse rate caused by infiltration anesthesia for stereotactic frame fixation. Thus, application of Vapocoolant spray in addition to EMLA cream is highly recommended as a nursing intervention for patients undergoing gamma knife surgeries.

• 한국식품영양학회지
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• 제14권4호
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• pp.329-332
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• 2001

The antimutagenic activity of resveratrol on the mutagenicity induced by Trp P-1 (3-amino-1,4-dime-thyl-5H-pyrido{4,3-b}indole) was studied using the Ames test with Salmonella typhimurium TA98 and 100. Trp P-1 showed strong mutagenecity in S. typhimurium TA98, but was higly decreased mutagenecity in S. typhimurium TA100. This result suggests that the mutagenecity of Trp P-1 can be mainly induced by the DNA lesions causing frame shift. Resveratrol itself did not show antibacterial effect upon 300 $\mu\textrm{g}$/assay. Resveratrol showed the strongest inhibitory effect with dose dependent manner on the mutagenicity induced by Trp P-1. The inhibition rates of resveratrol at concentration of 2, 10, 25, 50, 100, 300 $\mu\textrm{g}$/assay were 13%, 37%, 52%, 65%, 81%, 89%, respectively.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2013년도 하계학술대회
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• pp.405-406
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• 2013

현재 MPEG 에서 표준화 중인 IVC(Internet Video Coding)에서는 저지연 모드 부호화 구조에서 비참조 P 프레임 부호화 기법을 선택적으로 사용하여 2% 비트율 이득을 얻고 있다. 기존의 비참조 P 프레임 기법은 움직임 벡터(MV)의 크기를 이용하여 적응적으로 고정된 부호화 구조의 비참조 P 프레임을 적용하고 있으나 시퀀스에 따라서 오히려 부호화 성능이 크게 떨어지는 단점이 있다. 본 논문에서는 IVC 시험모델(ITM4.0)에 채택되어 있는 적응적 비참조 P 프레임 부호화 성능을 개선하기 위하여 기존의 고정된 비참조 P 프레임의 구조를 변경하는 기법과 MV 와 함께 프레임별 발생 비트량을 함께 사용하는 기법을 제시한다. 실험결과 제안된 기법은 시퀀스에 따른 큰 성능 저하 없이 ITM4.0 대비 3.0% 정도의 비트율 감소를 얻음을 확인하였다.

• Steel and Composite Structures
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• 제3권6호
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• pp.403-420
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• 2003

In the paper one investigates the benefits deriving from the introduction of SMA provisions in a structure subject to dynamic excitation and vertical loads. At this purpose one considers a multi-degree-of-freedom (mdof) shear elastic-plastic frame and designs couples of super-elastic SMA tendons to be placed at critical locations of the structure. Particular attention is focused on the reduction of $P-{\Delta}$ effects.

• Journal of Applied Biological Chemistry
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• 제64권3호
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• pp.213-216
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• 2021

A gene encoding thermostable cellulase A (TmCelA) was isolated from Thermotoga maritima. The open reading frame of TmCelA gene was 774 bp long which predicted to encode 257 amino acid residues with a molecular weight of 29,732 Da. To examine the biochemical properties, the TmCelA was overexpressed in E. coli BL21, and expressed protein was purified. The optimum temperature of recombinant TmCelA was 90-95 ℃, and the optimum pH of recombinant TmCelA was approximately pH 5.0. Recombinant TmCelA was stable at temperature below 90 ℃.