• 한국전산구조공학회논문집
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• 제28권2호
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• pp.123-130
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• 2015

본 논문에서는 전자기파에 대한 수치적 파동흡수 경계모델인 Perfectly-Matched-Layer(PML)를 개발하고 PML을 연동시킨 유한요소법에 의해 콘크리트 구조물을 통과하는 마이크로파의 전파거동을 해석하는 수치적 기법을 제시한다. 콘크리트 부재와 공기로 구성된 무한매질을 PML을 경계로 하는 유한영역으로 치환하고, 이 유한영역에서 평면 전자기파에 대한 시간 영역 맥스웰방정식의 수치 해를 혼합유한요소법에 의해 계산하였다. 공기로만 이루어진 균일매질의 경우와 콘크리트 구조물이 존재하는 비균일 매질의 경우에 대하여 단일주파수 및 복합주파수를 갖는 마이크로파의 전기장을 계산하였고, 오차분석을 위해 $L^2$-놈 형태로 표현되는 정해와 수치 해의 상대오차를 정의하여 수치 해의 정확도를 평가하였다. 이 연구는 마이크로파를 이용한 철근콘크리트 구조물의 건전도평가 및 손상평가에 적용될 수 있다.

• 한국전산구조공학회논문집
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• 제29권6호
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• pp.521-527
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• 2016

본 논문은 효과적인 무반사 기법을 이용한 수중폭발에 따른 부유식 해상풍력발전기의 동응답 수치해석에 관한 내용이다. 수치해석을 위해 무한한 바다 영역을 유한한 영역으로 한정하고 그 경계에서 필연적인 충격파의 반사를 흡수하기 위해 PML(perfectly matched layer)이라 불리는 무반사 기법을 적용하였다. 수중폭발을 수반한 비점성 압축성 유동을 표현하는 일반화된 수송방정식은 방향별 흡수계수와 상태변수를 도입하여 3개의 PML 방정식으로 분리하였다. 풍력발전기와 해수 유동으로 구성된 유체-구조 연계문제는 오일러 기반의 유한체적법과 라그랑지 기반의 유한요소법을 연계하여 반복계산으로 해석하였다. 그리고 수중폭발에 따른 동수압은 JWL 상태방정식으로 계산하였다. 수치실험을 통해 수중폭발에 따른 동수압과 구조 동응답을 분석하였으며, PML 무반사 기법을 적용한 경우가 그렇지 않은 경우에 비해 보다 정확한 해석결과를 제공함을 확인하였다.

• Structural Engineering and Mechanics
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• 제50권3호
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• pp.349-364
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• 2014

Perfectly matched layers are employed in time harmonic analysis of dam-foundation systems. The Lysmer boundary condition at the truncation boundary of the PML region has been incorporated in the formulation of the dam-foundation FE model (including PML). The PML medium is defined in a way that the formulation of the system can be transformed into time domain. Numerical experiments show that applying Lysmer boundary conditions at the truncation boundary of the PML area reduces the computational cost and make the PML approach a more efficient technique for the analysis of dam-foundation systems.

• 종양간호연구
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• 제9권2호
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• pp.114-121
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• 2009

Purpose: This study was to explore the hope structures of the newly diagnosed cancer patients by examining the relationships between hope and the three concepts of 'Personal Spirit', 'Risk' and 'Authentic Caring' which composed the multidimensions of the Nekolaichuk and Bruera's hope model. Methods: Data was collected via survey from 32 newly diagnosed cancer patients. The perceived meaning of life (PML) for 'personal spirit', perceived confidence in cure (PCC) for 'risk', and perceived family support (PFS) and perceived support from medical team (PSM) for 'authentic caring' were adapted from the definitions of the concepts in the model. Hope, PML, and PCC were measured with VAS. PFS and PSM were measured with Korean version of 'Cobb's family support scale', which was modified by Kang. Pearson correlation coefficients were used to identify the relationships among the concepts. Results: The significant relationships were revealed between hope and PCC (p<.001), hope and PML (p<.001), PML and PCC (p<.001), PFS and PML (p=.030), and PSM and PML (p=.047). Conclusion: The newly diagnosed cancer patients experience hope in different ways. The cancer patients' hope immediate after diagnosis, however, is most likely to be experienced as seeking balance between uncertainty about cancer treatment and the meaning of life.

• Journal of Ginseng Research
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• 제45권2호
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• pp.295-304
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• 2021

Background: Acute promyelocytic leukemia (APL) is a hematopoietic malignancy driven by promyelocytic leukemia-retinoic acid receptor A (PML-RARA) fusion gene. The therapeutic drugs currently used to treat APL have adverse effects. 20(S)-ginsenoside Rh2 (GRh2) is an anticancer medicine with high effectiveness and low toxicity. However, the underlying anticancer mechanisms of GRh2-induced PML-RARA degradation and apoptosis in human APL cell line (NB4 cells) remain unclear. Methods: Apoptosis-related indicators and PML-RARA expression were determined to investigate the effect of GRh2 on NB4 cells. Z-VAD-FMK, LY294002, and C 87, as inhibitors of caspase, and the phosphatidylinositol 3-kinase (PI3K) and tumor necrosis factor-α (TNF-α) pathways were used to clarify the relationship between GRh2-induced apoptosis and PML-RARA degradation. Results: GRh2 dose- and time-dependently decreased NB4 cell viability. GRh2-induced apoptosis, cell cycle arrest, and caspase3, caspase8, and caspase9 activation in NB4 cells after a 12-hour treatment. GRh2-induced apoptosis in NB4 cells was accompanied by massive production of reactive oxygen species, mitochondrial damage and upregulated Bax/Bcl-2 expression. GRh2 also induced PML/PML-RARA degradation, PML nuclear bodies formation, and activation of the downstream p53 pathway in NB4 cells. Z-VAD-FMK inhibited caspase activation and significantly reversed GRh2-induced apoptosis and PML-RARA degradation. GRh2 also upregulated TNF-α expression and inhibited Akt phosphorylation. LY294002, an inhibitor of the PI3K pathway, enhanced the antitumor effects of GRh2, and C 87, an inhibitor of the TNF-α pathway, reversed NB4 cell viability, and GRh2-mediated apoptosis in a caspase-8-dependent manner. Conclusion: GRh2 induced caspase-dependent PML-RARA degradation and apoptosis in NB4 cells via the Akt/Bax/caspase9 and TNF-α/caspase8 pathways.

• 한국지진공학회논문집
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• 제27권1호
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• pp.25-35
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• 2023

Considering the non-linear behavior of structure and soil when evaluating a nuclear power plant's seismic safety under a beyond-design basis earthquake is essential. In order to obtain the nonlinear response of a nuclear power plant structure, a time-domain SSI analysis method that considers the nonlinearity of soil and structure and the nonlinear Soil-Structure Interaction (SSI) effect is necessary. The Boundary Reaction Method (BRM) is a time-domain SSI analysis method. The BRM can be applied effectively with a Perfectly Matched Layer (PML), which is an effective energy absorbing boundary condition. The BRM has a characteristic that the magnitude of the response in far-field soil increases as the boundary interface of the effective seismic load moves outward. In addition, the PML has poor absorption performance of low-frequency waves. For this reason, the accuracy of the low-frequency response may be degraded when analyzing the combination of the BRM and the PML. In this study, the accuracy of the analysis response was improved by adjusting the PML input parameters to improve this problem. The accuracy of the response was evaluated by using the analysis response using KIESSI-3D, a frequency domain SSI analysis program, as a reference solution. As a result of the analysis applying the optimal PML parameter, the average error rate of the acceleration response spectrum for 9 degrees of freedom of the structure was 3.40%, which was highly similar to the reference result. In addition, time-domain nonlinear SSI analysis was performed with the soil's nonlinearity to show this study's applicability. As a result of nonlinear SSI analysis, plastic deformation was concentrated in the soil around the foundation. The analysis results found that the analysis method combining BRM and PML can be effectively applied to the seismic response analysis of nuclear power plant structures.

• International Journal of Oral Biology
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• 제37권3호
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• pp.91-102
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• 2012

Bcl-2 protects tumor cells from the apoptotic effects of various anti-neoplastic agents. Increased expression of Bcl-2 has been associated with a poor response to chemotherapy in various malignancies, including leukemia. Hence, bypassing the resistance conferred by anti-apoptotic factors such as Bcl-2 represents an attractive therapeutic strategy against cancer cells, including leukemic cells. This study was undertaken to examine whether the anticancer drug, cisplatin and the synthetic chenodeoxycholic acid (CDCA) derivative, HS-1200 show anti-tumor activity in U937 and U937/Bcl-2 cells. Viability assays revealed that HS-1200 overcomes the resistance conferred by Bcl-2 in human leukemic U937 cells. Various apoptosis assessment assays further demonstrated that HS-1200 overcomes the resistance conferred by Bcl-2 in human leukemic U937 cells by inducing apoptosis. In addition HS-1200, but not cisplatin, overcomes the anti-apoptotic effects of Bcl-2 in Bcl-2 over-expressing human leukemic cells (U937/Bcl-2 cells). Notably, we observed that the HS-1200-induced formation of mature promyelocytic leukemia (PML) nuclear bodies (NBs) correlates with a suppression of the anti-apoptotic effects of Bcl-2 in human leukemic cells over-expressing this protein (U937/Bcl-2 cells). Furthermore, HS-1200 was found to induce the association between PML and SUMO-1, Daxx, Sp100, p53 or CBP in the aggregated PML-NBs of U937/Bcl-2 cells. Thus, PML protein and the formation of mature PML-NBs could be considered as therapeutic targets that may help to bypass the resistance to apoptosis conferred by Bcl-2. Elucidating the exact mechanism by which PML regulates Bcl-2 will require further work.

• 한국정보통신학회논문지
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• 제9권4호
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• pp.712-719
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• 2005

인터넷과 컴퓨터 네트워크의 발전에 힘입어 차세대 컴퓨팅 패러다임으로 유비쿼터스 컴퓨팅이 등장하였고, 이를 실현하기 위한 핵심 기술로 RFID(Radio Frequency Identification) 기술이 주목받고 있다. 이러한 RFID 응용 시스템에서 상호간의 데이터 교환을 위해 MIT Auto-ID Center 에서는 물리적 객체의 정보를 표현하기 위한 표준 언어로 XML(Extensible Markup Language) 기반의 PML(Physical Markup Language)을 제안하여 사용하고 있다. 하지만 Auto-ID Center에서 제시한 PML은 객체의 정보를 기술하기 위한 핵심부분만 정의 되어 있고, 실제 적용에 필요한 부분은 별도로 확장 정의하여 사용하도록 되어 있다. 이에 본 논문에서는 Auto-ID Center의 PML Core에 기반하여 RFID 응용 서비스에서 전자태그 정보 처리를 위해 사용될 수 있는 객체 타입을 정의하고 물류 유통 서비스 분야에 적용할 수 있도록 객체 정보 데이터 모델을 설계하였다.

• 지능정보연구
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• 제11권2호
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• pp.105-121
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• 2005

EPC를 탑재한 RFID 형태의 스마트객체를 이용한 물류 시스템을 구축하기 위해서는 시스템 구성 요소간의 거래에 필수적인 RFID 객체의 PML 데이터를 표현하고 검색요구에 대응하는 RFID 정보서비스의 설계 및 관리가 매우 중요하다. EPC기반 RPID 정보서비스는 네트워크상의 정보시스템들에 보안과 운영의 이유로 분산되어 있는 RFID 객체 정보들을 검색하여 사용자가 요구하는 결과를 반환하는 역할을 담당한다. 하지만 RFID 객체 정보의 표준화된 표현과 처리, 그리고 분산처리로 인한 통신량과 처리시간 과다의 문제가 존재한다. 이에 대해서 본 연구는 물류시스템의 PML 데이터의 표현 및 사용, 검색패턴을 분석하고, 분석 결과를 기반으로 미들웨어를 이용하는 분산형 RFID 객체 데이터 관리 및 RFID 객체 정보서비스 구조를 설계하고 제시하였다. 단일형 및 통합형 RFID 정보서비스 구조를 제시하였다.

• 한국전자파학회논문지
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• 제11권4호
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• pp.592-598
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• 2000

The existin Berenger's PML(Perfectly Matched Layer) cannot absorb evanescent modes effectively generated in waveguides or periodic array structures. Although some absorbing boundary conditons(ABC) were introduced to absorp the evanescent modes, they did not show sufficient performance or could not be applied easily because of their much difference from Berengers PML. In this paper, NPML(New PML) is introduced to absorb the evanescent modes by splitting the conductivity and permittivity profile of the Berengers PML. The proposed NPML is certified as an ABC having enough performance for evanescent and propagating modes by analyzing the global error and the reflectivity of a waveguide.