• 한국자기공명학회논문지
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• 제18권2호
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• pp.58-62
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• 2014

Human transmembrane proteins (hTMPs) are closely related to transport, channel formation, signaling, cell to cell interaction, so they are the crucial target of modern medicinal drugs. In order to study the structure and function of these hTMPs, it is important to prepare reasonable amounts of proteins. However, their preparation is seriously difficult and time-consuming due to insufficient yields and low solubility of hTMPs. We tried to produce large amounts of Syndecan-4 transmembrane domain (Syd4-TM) that is related to the healing wounds and tumor for a long time. In this study, we performed the structure determination of Syd4-TM combining the Polarity Index at Slanted Angle (PISA) wheel pattern analysis based on $^{15}N-^1H$ 2D SAMPI-4 solid-state NMR of expressed Syd4-TM and Molecular Dynamics (MD) simulation using Discovery Studio 3.1.

• Earthquakes and Structures
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• 제14권3호
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• pp.187-201
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• 2018

The paper describes a modified cyclic bar model including bond-slip phenomena between steel reinforcing bars and surrounding concrete. The model is focused on plain bar and is useful, for its simplicity, for the seismic analyses of RC structures with plain bars and insufficient constructive details, such as in the case of '60s -'70s Mediterranean buildings. The model is based on an imposed exponential displacements field along the bar including both steel deformation and slip; through the adoption of equilibrium and compatibility equations a stress-slip law can be deducted and simply applied, with opportune operations, to RC numerical models. This study aims to update and complete the original monotonic model published by the authors, solving some numerical inconsistencies and, mostly, introducing the cyclic formulation. The first aim is achieved replacing the imposed linear displacement field along the bar with an exponential too, while the cyclic behaviour is described through a formulation based on the results of parametric analyses concerning a large range of steel and concrete properties and geometric configurations. Validations of the proposed model with experimental results available in the current literature confirm its accuracy and the reduced computational burden, highlighting its suitability in performing nonlinear analyses of RC structures.

• Geomechanics and Engineering
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• 제20권5호
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• pp.433-445
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• 2020

A new code, called PRaFULL (Piled Raft Foundation Under Lateral Load), was developed for the analysis of laterally loaded Combined Pile Raft Foundation (CPRF). The proposed code considers the contribution offered by the raft-soil contact and the interactions between all the CPRF system components. The nonlinear behaviour of the reinforced concrete pile and the soil are accounted. As shallower soil layers are of great relevance in the lateral response of a pile foundation, PRaFULL includes the possibility to consider layered soil profiles with appropriate properties. The shadowing effect on the ultimate soil pressure is accounted, when dealing with pile groups, as proposed by the Strain Wedge Model. PRaFULL BEM code obviously requires less computational resources compared to FEM (Finite Element Method) or FDM (Finite Difference Method) codes. The proposed code was validated in the linear elastic range by comparisons with the code APRAF (Analysis of Piled Raft Foundations). The reliability of the procedure to predict piled raft performance was then verified in nonlinear range by comparisons with both centrifuge tests and computer code PRAB.

• Nuclear Engineering and Technology
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• 제39권5호
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• pp.627-636
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• 2007

The present work is aimed at further discussing the effectiveness of dimensionless parameters recently proposed for the analysis of flow stability in heated channels with supercritical fluids. In this purpose, after presenting the main motivations for the introduction of these parameters in place of previously proposed ones, additional information on the theoretical bases and on the consequences of this development is provided. Stability maps, generated by an in-house program adapted from a previous application to boiling channels, are also shown for different combinations of the operating parameters. The maps are obtained as contour plots of an amplification parameter obtained from numerical discretization and subsequent linearization of governing equations; as such, they provide a quantitatively clear perspective of the effect of different boundary conditions on the stability of heated channels with supercritical fluids. In order to assess the validity of the assumptions at the basis of the in-house model, supporting calculations have been performed making use of the RELAP5/MOD3.3 computer code, detecting the values of the dimensionless parameters at the threshold for the occurrence of instability for a heated channel representative of SCWR proposed core configurations. The obtained results show reasonable agreement with the maps, supporting the applicability of the proposed scaling parameters for describing the dynamic behaviour of heated channels with supercritical fluids.

• Journal of Periodontal and Implant Science
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• 제53권5호
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• pp.347-361
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• 2023

Purpose: Exosomes are membrane vesicles that are present in body fluids and contain proteins, lipids, and microRNA (miRNA). Periodontal tissue examinations assess the degree of periodontal tissue destruction according to the probing depth (PD), clinical attachment loss (CAL), bleeding on probing, and X-ray examinations. However, the accurate evaluation of the prognosis of periodontitis is limited. In this study, we collected saliva from patients before and after initial periodontal therapy (IPT) and compared changes in the clinical parameters of periodontitis with changes in the components of salivary exosomes. Methods: Saliva was collected from patients with stage III and IV periodontitis at the first visit and post-IPT. Exosomes were purified from the saliva, and total protein and RNA were extracted. Changes in expression levels of C6, CD81, TSG101, HSP70, and 6 kinds of miRNA were analyzed by western blots and real-time polymerase chain reaction. Results: Patients with increased C6 expression after IPT had significantly higher levels of periodontal inflamed surface area (PISA), miR-142, and miR-144 before and after IPT than patients with decreased C6 expression after IPT. Patients with decreased and unchanged CD81 expression after IPT showed significantly higher PD, CAL, and PISA before IPT than after IPT. Patients with decreased and unchanged TSG101 expression after IPT had significantly higher PD before IPT than after IPT. Patients with increased HSP70 expression after IPT had significantly higher PD and PISA before and after IPT than patients with unchanged HSP70 after IPT. The expression levels of miR-142, miR-144, miR-200b, and miR-223 changed with changes in the levels of C6, CD81, TSG101, and HSP70 in the salivary exosomes of periodontitis patients before and after IPT. Conclusions: The expression levels of proteins and miRNAs in salivary exosomes significantly changed after IPT in periodontitis patients, suggesting that the components of exosomes could serve as biomarkers for periodontitis.

• 한국광학회:학술대회논문집
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• 한국광학회 2002년도 하계학술발표회
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• pp.2-2
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• 2002

검은공진현상은 양자광학현상으로 비흡수 공진으로 간단히 표현할 수 있다. 즉, 공진전이에서 광흡수가 일어나지 않는 현상인데 이는 1976년 Pisa대학에서 분광학 실험으로 우연히 관측된 이래 90년대 이후 수많은 응용분야가 제시되면서 검은공진 연구에 있어 비약적인 발전을 가져오게 된다. 그 중 비선형광학, 밀도전이 없는 레이저, 양자메모리, 고해상 분광학, 광스위치, 빛속도조절 등은 그 좋은 예이다. (중략)

• 대한수학회지
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• 제50권2호
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• pp.379-392
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• 2013

A general result for the complete convergence of arrays of rowwise extended negatively dependent random variables is derived. As its applications eight corollaries for complete convergence of weighted sums for arrays of rowwise extended negatively dependent random variables are given, which extend the corresponding known results for independent case.

• 대한수학회지
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• 제60권5호
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• pp.1135-1136
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• 2023

In this erratum, we offer a correction to [J. Korean Math. Soc. 60 (2023), No. 1, pp. 115-141]. We rectify Theorem 5.7 and Table 1 of the original paper.

• 컴퓨터교육학회논문지
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• 제17권2호
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• pp.77-86
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• 2014

국제 학업 성취도인 PISA2007, TIMSS 2011에 의하면 우리나라 학생들의 수학, 과학 학업성취도는 최상위에 해당하지만, 관련 태도가 낮다는 결과가 나왔다. 또, 사회에 만연한 이공계 기피현상, 초중고에서 점점 사라지고 있는 정보과학 교육의 현실을 반영하는 학습 경험을 제공해야 할 필요성이 제기되었다. 이러한 필요성에 의해 본 연구자는 2012년에 Physical Computing 기반의 STEAM 프로그램을 개발하고 그 효과를 연구하였다. 그 결과 과학적 문제해결력, 과학적 태도, 인성 등에서 향상되는 결과를 얻었다. 본 연구에서는 2012년 연구의 후속연구이다. STEAM 프로그램을 적용하여 향상을 가져 온 4학년 학생들이 1년 후에 STEAM 교육을 받지 않았을 때 학생들에게 어떤 변화가 생겼는가를 연구하였다. 분석 방법은 4학년 초, STEAM 교육을 받은 4학년말, STEAM 교육을 받지 않은 5학년말의 검사 결과를 비교하였다. 그 결과 과학적 탐구에 대한 태도를 제외한 모든 영역에서 STEAM 교육을 받지 않은 5학년말은 4학년 초에 비해 향상이 없는 결과를 얻었다. 이것은 STEAM 교육의 필요성에 대한 역설적인 증거라고 할 수 있다.

• 한국수학교육학회지시리즈A:수학교육
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• 제59권2호
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• pp.185-199
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• 2020

이 연구의 목적은 수학에 인문학적 상상력을 접목하는 것이 수학교육에 주는 의미를 논의하고, 수학교육에 시사점을 제안하는 것이다. 전통적으로 수학은 추상적 사고를 대상으로 하기 때문에 우리의 삶의 문제와는 거리가 있다고 인식되었다. TIMSS나 PISA와 같은 국제 연구에 따르면, 우리나라 학생들의 수학학업성취도는 다른 선진 국가들의 학생들에 비하여 상대적으로 높으나, 수학에 대한 태도는 매우 부정적이고 삶에 대한 만족도도 낮은 편이다. 수학과 인문학적 상상력을 연계하여 학습하도록 하는 것은 학생들에게 인간의 삶의 문제에 대하여 인문학적인 관점으로 보도록 한다. 이 연구에서는 수학교육을 위한 수학과 인문학적 상상력을 접목의 의미를 생각해 보고, 학교의 수학교육에서 적용해 볼 수 있는 몇 가지 사례를 소개한다. 연구자는 수학을 배우는 궁극적인 이유는 학습자로 하여금 깨달음을 얻도록 하는 것이고, 모두가 보다 행복한 삶을 살아가기 위한 것이어야 한다고 주장한다.