• 폴리머
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• 제28권6호
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• pp.551-555
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• 2004

셀룰로오스 디아세테이트에 다양한 종류의 가소제와 몬모릴로나이트를 메틸렌 클로라이드/에탄올 (9:1 w/w) 혼합용매에 첨가해 나노복합 필름 (nanocomposite film)을 제조하였다. 시차 주사 열분석 (DSC)을 이용하여 제조된 셀룰로오스 디아세테이트 필름의 열적 특성 (T$_{g}$)을 관찰하였으며, 가소제 함량이 증가함에 따라 T$_{g}$가 감소함을 관찰할 수 있었다. X-ray 회절 (XRD)을 이용하여 셀룰로오스 디아세테이트 필름내에서 몬모릴로나이트가 분산되는 정도를 관찰하였으며, 인장 강도와 인장 탄성률을 측정하여 셀룰로오스 디아세테이트 필름의 기계적 물성을 관찰하였다. 가소제의 함량을 30 wt%까지 증가시켰을 때 인장 탄성률은 1930 MPa에 1131 MPa로 감소하였고, 몬모릴로나이트의 함량을 7 wt%까지 증가시켰을 때 1731 MPa에서 2272 MPa로 증가하였다. 셀룰로오스 디아세테이트 필름의 기계적 물성은 가소제를 첨가할수록 감소하지만, 몬모릴로나이트의 첨가로 강화시킬 수 있다.다.

• Archives of Pharmacal Research
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• 제18권5호
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• pp.336-339
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• 1995

Ephedra distachya cultures have been known to accumulate two major $\rho-coumaroylamino$ acids (p-coumaroylgicine and $\rho-coumaroylamino$ -D-alanine) by D-Ala treament. When D-Ala was added together with serial concentrations of yeast-derived elicitor, the accumulation of $\rho-coumaroylamino$ -D-Ala $(\rho-CDA)$ was geatly increased in an additive manner. In feeding experiments, $[1-^14C]$-D-Ala was incorporated into $\rho-CDA$at a rate of 2.2% or 2.3% of added radioactivity, indicating that exogenous D-Ala served as a precursor of the conjugate. $[1-^14C]$-L-Ala wasalso incorporated into p-CDA (0.23%) in the elicitor treated cultures. This fact suggested that at least a part of $(\rho-CDA)$ was produced from active conversion of L-Ala by the elecitation. In order to investigate a possible role of D-Ala as an elicitor of $\rpo-coumaroylamino$ acids $(\rpo-CAA)$, cold D-Ala was added together with labeled L-Ala. Although L-Ala seemed to be incorporated into $\rho-CDA$ by this treatment, the incorporation ratio was too small (0.054%) to draw a clear conclusion. However, the amount of $\rpo-coumaroylglycine$, which did not use D-Ala as a substrate, was also sightly increased by D-Ala treatment irrespective of the presence of elicitor, suggesting that exogenous D-Ala might act as an elicitor of$\rpo-CAA$ as well as a precusor substrate of $\rho-CDA$.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2007년도 한국컴퓨터종합학술대회논문집 Vol.34 No.1 (A)
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• pp.101-102
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• 2007

• Journal of Microbiology and Biotechnology
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• 제19권12호
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• pp.1536-1541
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• 2009

The DNA shuffling technique has been used to generate libraries of evolved enzymes in thermostability. We have shuffled two thermostable cytidine deaminases (CDAs) from Bacillus caldolyticus DSM405 (T53) and B. stearothermophilus IFO12550 (T101). The shuffled CDA library (SH1067 and SH1077 from the first round and SH2426 and SH2429 from the second round) showed various patterns in thermostability. The CDAs of SH1067 and SH1077 were more thermostable than that of T53. SH2426 showed 150% increased halftime than that of T53 at $70^{\circ}C$. The CDA of SH2429 showed about 200% decreased thermostability than that of T53 at $70^{\circ}C$. A single amino acid residue replacement that presented between SH1077 and SH2429 contributed to dramatic changes in specific activity and thermostability. On SDS-PAGE, the purified CDA of SH1077 tetramerized, whereas that of SH2429 denatured and became almost monomeric at $80^{\circ}C$. A simulated three-dimensional structure for the mutant CDA was used to interpret the mutational effect.

• 한국초전도ㆍ저온공학회논문지
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• 제18권1호
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• pp.55-58
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• 2016

Quench Detection System (QDS) is essential to guarantee the stable operation of the Korea Superconducting Tokamak Advanced Research (KSTAR) Poloidal Field (PF) magnet system because the stored energy in the magnet system is very large. For the fast response, voltage-based QDS has been used. Co-wound voltage sensors and balanced bridge circuits were applied to eliminate the inductive voltages generated during the plasma operation. However, as the inductive voltages are hundreds times higher than the quench detection voltage during the pulse-current operation, Central Difference Averaging (CDA) and MIK, where I and K stand for mutual coupling indexes of different circuits, which is an active cancellation of mutually generated voltages have been suggested and studied. In this paper, the CDA and MIK technique were applied to the KSTAR magnet for PF magnet quench detection. The calculated inductive voltages from the MIK and measured voltages from the CDA circuits were compared to eliminate the inductive voltages at result signals.

• International Journal of Fluid Machinery and Systems
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• 제3권1호
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• pp.20-28
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• 2010

This paper deals with the Design and Analysis of a Controlled Diffusion Aerofoil (CDA) Blade Section for an Axial Compressor Stator and Effect of incidence angle and Mach No. on Performance of CDA. CD blade section has been designed at Axial Flow Compressor Research Lab, Propulsion Division of National Aerospace Laboratories (NAL), Bangalore, as per geometric procedure specified in the U.S. patent (4). The CFD analysis has been performed by a 2-D Euler code (Denton's code), which gives surface Mach No. distribution on the profiles. Boundary layer computations were performed by a 2-D boundary layer code (NALSOF0801) available in the SOFFTS library of NAL. The effect of variation of Mach no. was performed using fluent. The surface Mach no. distribution on the CD profile clearly indicates lower peak Mach no. than MCA profile. Further, boundary layer parameters on CD aerofoil at respective incidences have lower values than corresponding MCA blade profile. Total pressure loss on CD aerofoil for the same incidence range is lower than MCA blade profile.

• 응용통계연구
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• 제30권1호
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• pp.83-93
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• 2017

k (${\geq}2$) 그룹의 p-차원 데이터의 시각화에서 가장 전형적인 방법은 Fisher의 정준판별분석(canonical discriminant analysis; CDA)이다. CDA는 마할라노비스 공간에서 k개 그룹 중심을 근사하게 통과하는 저차원 부공간에 관측점들을 사영한다. 본 논문은 척도화 유클리드 공간에서 다그룹 다차원 데이터를 시각화하는 방법을 제안하는데, 저차원 부공간의 제1축(또는 제1축과 제2축)은 그룹 중심들의 최대변별(maximum discrimination)에서 찾고 부공간의 제2축(또는 제3축)은 관측개체들의 최대산포(maximum dispersion)에서 찾는다. 이러한 혼종방법(hybrid method)은 2-그룹 다차원 자료의 시각화에서 특히 유용하다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권4호
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• pp.1594-1617
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• 2018

In this paper, we consider a spectrum access scenario which consists of two groups of users, namely Primary Users (PUs) and Secondary Users (SUs) in Cooperative Cognitive Radio Networks (CCRNs). SUs cooperatively relay PUs messages based on Amplify-and-Forward (AF) and Decode-and-Forward (DF) cooperative techniques, in exchange for accessing some of the spectrum for their secondary communications. From the literatures, we found that the Conventional Distributed Algorithm (CDA) and Pragmatic Distributed Algorithm (PDA) aim to maximize the PU sum-rate resulting in a lower sum-rate for the SU. In this contribution, we have investigated a suit of distributed matching algorithms. More specifically, we investigated SU-based CDA (CDA-SU) and SU-based PDA (PDA-SU) that maximize the SU sum-rate. We have also proposed the All User-based PDA (PDA-ALL), for maximizing the sum-rates of both PU and SU groups. A comparative study of CDA, PDA, CDA-SU, PDA-SU and PDA-ALL is conducted, and the strength of each scheme is highlighted. Different schemes may be suitable for different applications. All schemes are investigated under the idealistic scenario involving perfect coding and perfect modulation, as well as under practical scenario involving actual coding and actual modulation. Explicitly, our practical scenario considers the adaptive coded modulation based DF schemes for transmission flexibility and efficiency. More specifically, we have considered the Self-Concatenated Convolutional Code (SECCC), which exhibits low complexity, since it invokes only a single encoder and a single decoder. Furthermore, puncturing has been employed for enhancing the bandwidth efficiency of SECCC. As another enhancement, physical layer security has been applied to our system by introducing a unique Advanced Encryption Standard (AES) based puncturing to our SECCC scheme.

• 대한기계학회논문집B
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• 제38권11호
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• pp.873-879
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• 2014

CDA(Clean Dry Air) System 에서 공기 압축기는 핵심 설비이자 소비되는 전력의 대부분을 차지한다. 그리하여 압축기 성능(ECI)을 개선함으로써 CDA System 전체성능을 크게 향상 시킬 수 있다. 종래의 많은 연구를 통해 인입공기의 온/습도 조건이 압축기에 미치는 영향에 대해 잘 알려져 있으나, 본 연구에서는 인입공기의 조건에 따라 소비되는 실제 전력 및 토출유량의 상관관계를 조사하였다. 또한 증발 냉각장치를 설치하여 인입공기 조건의 다양한 변화를 통하여 압축기성능에 미치는 영향을 연구하였다. 얻어진 결과로부터 인입공기의 온/습도가 낮을수록 압축기성능이 개선되었고, 증발냉각장치를 설치하였을 때 압축기성능이 개선됨을 알았다.

• Journal of Microbiology and Biotechnology
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• 제32권4호
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• pp.504-513
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• 2022

Chitin deacetylase (CDA) inhibitors were developed as novel antifungal agents because CDA participates in critical fungal physiological and metabolic processes and increases virulence in soil-borne fungal pathogens. However, few CDA inhibitors have been reported. In this study, 150 candidate CDA inhibitors were selected from the commercial Chemdiv compound library through structure-based virtual screening. The top-ranked 25 compounds were further evaluated for biological activity. The compound J075-4187 had an IC50 of 4.24 ± 0.16 µM for AnCDA. Molecular docking calculations predicted that compound J075-4187 binds to the amino acid residues, including active sites (H101, D48). Furthermore, compound J075-4187 inhibited food spoilage fungi and plant pathogenic fungi, with minimum inhibitory concentration (MIC) at 260 ㎍/ml and minimum fungicidal concentration (MFC) at 520 ㎍/ml. Therefore, compound J075-4187 is a good candidate for use in developing antifungal agents for fungi control.