• 한국안광학회지
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• 제18권3호
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• pp.305-311
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• 2013

목적: 간헐외사시의 비수술적 치료법들 중의 하나인 과교정 (-)렌즈 처방이 입체시와 사시각에 미치는 영향에 대해 연구하였다. 방법: 2011년 10월부터 2011년 12월까지 전남대학교 병원에서 간헐외사시로 진단받은 환자 24명을 대상으로 -1.00, -2.00, 그리고 -3.00 D의 단계적인 과교정 (-)렌즈를 착용하게 한 후 근거리(33 cm)와 원거리(6 m)에서 사시각(prism diopter, ${\Delta}$), 입체시(second of arc, arcsec), 양안시력(LogMAR), 사시조절능력(control of exodeviation) 및 워쓰4등검사를 이용한 융합력의 변화를 측정하였다. 결과: 과교정 전의 평균 사시각은 근거리 $20.9{\pm}9.7$ ${\Delta}$, 원거리 $23.0{\pm}7.5$ ${\Delta}$이다. -1.00, -2.00, -3.00 D의 (-)렌즈 착용 시 근거리 사시각은 각각 $18.5{\pm}10.0$ ${\Delta}$ (p<0.01), $15.8{\pm}9.0$ ${\Delta}$ (p<0.01), 그리고 $14.0{\pm}9.1$ ${\Delta}$ (p<0.01)로 의미 있게 감소하였으며, 원거리 사시각은 -2.00 D 및 -3.00D의 렌즈 착용 시 각각 $21.4{\pm}5.2$ ${\Delta}$ (p=0.01), $19.6{\pm}6.3$ ${\Delta}$ (p<0.01)으로 감소하였다. 이에 반하여 양안시력, 사시조절능력, 융합력, 입체시는 과교정 (-)렌즈를 처방하더라도 의미 있는 감소를 보이지 않고 유지되었다(p>0.05). 결론: 간헐외사시에서 과교정 (-)렌즈 처방은 근거리 및 원거리 외사시각을 줄일 수 있는 효과적인 방법이며 과교정 시 양안시력과 입체시는 감소하지 않고 유지됨을 알 수 있었다.

• Kyungpook Mathematical Journal
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• 제46권4호
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• pp.603-613
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• 2006

Near-rings considered are right near-rings and R is a near-ring. $J_0^r(R)$, the right Jacobson radical of R of type-0, was introduced and studied by the present authors. In this paper $J_1^r(R)$ and $J_2^r(R)$, the right Jacobson radicals of R of type-1 and type-2 are introduced. It is proved that both $J_1^r$ and $J_2^r$ are radicals for near-rings and $J_0^r(R){\subseteq}J_1^r(R){\subseteq}J_2^r(R)$. Unlike the left Jacobson radical classes, the right Jacobson radical class of type-2 contains $M_0(G)$ for many of the finite groups G. Depending on the structure of G, $M_0(G)$ belongs to different right Jacobson radical classes of near-rings. Also unlike left Jacobson-type radicals, the constant part of R is contained in every right 1-modular (2-modular) right ideal of R. For any family of near-rings $R_i$, $i{\in}I$, $J_{\nu}^r({\oplus}_{i{\in}I}R_i)={\oplus}_{i{\in}I}J_{\nu}^r(R_i)$, ${\nu}{\in}\{1,2\}$. Moreover, under certain conditions, for an invariant subnear-ring S of a d.g. near-ring R it is shown that $J_2^r(S)=S{\cap}J_2^r(R)$.

• 한국안광학회지
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• 제11권3호
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• pp.193-200
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• 2006

정시이거나 근시성 굴절이상자 83명을 대상으로 전체 표본값과 원거리 사위별 표본값 및 표본그래프를 작성하여 분석한 결과 다음과 같은 결론을 얻었다. 1. 전체 표본값은 원거리 사위량: $1.12{\Delta}$ 외사위, 근거리 사위량: $0.50{\Delta}$ 외사위, 원거리 허성상대폭주력(N.R.C.): ${\times}$/11/5, 원거리 실성상대폭주력(P.R.C.): 10/20/8, 근거리 허성상대폭주력(N.R.C.): 11/21/5, 근거리 실성상대폭주력(P.R.C.): 10/20/8, 허성상대조절력(N.R.A.): +2.54D, 실성상대조절력: -2.60D로 측정되어 모건(Morgan)의 표준값괴는 약간의 차이가 있었으며 원거리의 표본값은 증가하였고 근거리의 표본값은 감소하여 나타났다. 2. 모건(Morgan)이 분류한 A, B, C군과 데이터의 상관관계는 서로 유기적이고 밀접하게 연결되어 시기능 분석시 적극적으로 활용될 수 있다고 판정되었다. 3. 원거리 사위별 그래프 분석을 통해 쉐어드(Sheard)와 퍼시벌(Percival) 기준을 적용한 경우 원거리 사위가 외사위에는 7~9프리즘 군 이상인 경우, 내사위에는 4~6프리즘 군 이상에서 프리즘 처방이 필요하도록 나타났다.

• 한국통신학회논문지
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• 제33권3C호
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• pp.271-280
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• 2008

M채널 NPR(Near-Perfect Reconstruction) pseudo-QMF(Quadrature Mirror Filter) 뱅크의 설계는 일반적으로 SF(Spectral Factorization) 접근 방식을 혼합하여 많이 사용하며, 분리와 합성 필터들은 프로토타입 저역통과 필터(prototype lowpass filter : p-LPF)를 코사인 변조하여 사용한다. 그러나 이 방식은 $2M^{-th}$ 대역 필터 $G(z)=z^{-(N-1)}H(z^{-1})H(z)$의 SF 방식에 의해 p-LPF H(z)을 설계하기 때문에 p-LPF가 선형위상을 갖지 못할 뿐만 아니라 진폭왜곡이 최적화되지도 않았다. 따라서 대부분의 방법들이 재생 진폭왜곡 보다는 중첩상쇄왜곡을 줄이기 위한 p-LPF 설계를 제안하였다. 본 논문에서는 NPR pseudo-QMF 뱅크 구현에 필요한 p-LPF 설계를 위해 폐쇄형전달함수를 갖는 선형위상의 Maxflat(maximally flat) FIR 필터를 이용하는 새로운 방식을 제안하였다. 또한 폐쇄형주파수함수를 이용하여 $2M^{-th}$ 대역 필터 $G(z)=H^2(z)$로 표현되는 2M개 채널들의 전체진폭응답이 단일응답을 갖도록 p-LPF H(z)을 최적화하는 방법이 제안되었다. 실험 결과 시스템 최대진폭 왜곡이 $3.5{\times}10^{-4}\;({\simeq}-70dB)$보다 적고 각 분리 및 합성 필터들의 저지대역 감쇠가 -100dB 이상의 매우 뛰어난 NPR pseudo-QMF 뱅크 설계가 가능함이 증명되었다.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1274-1274
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• 2001

An anharmonicity is a fundamental quantity shaping the potential for stretching OH vibration in phenol and its derivatives. The phenomenon is examined both by experimental and theoretical methods. FT-IR and NIR spectra of series of phenols derivatives were measured in the range of fundamental and first two Overtones of $_{s}(OH)$ Vibrations in $CCl_4$ solutions. The electronic influence of substituents on the analyzed frequencies is discussed and correlated with $pK_{a}$ parameters. Ab initio MP2/6-31G(d,p) and B3LYP/6-31G(g,p) calculations of the potential for proton movement in OH group were performed. Equilibrium structures were also determined. The frequencies of fundamental and overtones were calculated by Numerov-type procedure. The results of calculations are compared with the experimental data. The best linear correlations were obtained for the results of MP2/6-31G(d,p) calculations. It was shown that some structural parameters are especially sensitive on substitution. The linear correlations were found between those parameters and spectroscopic data. The results of calculation are compared with available crystallographic data.

• Journal of Photoscience
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• 제9권2호
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• pp.70-73
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• 2002

A cyanobacteria-like organism Aaryochloris marina performs oxygenic photosynthesis with near far-red light by the use of chlorophyll d. Reaction center chlorophyll (Chl) of Photosystem (PS) II of A. marina was studied by analysis of millisecond-delayed fluorescence. Delayed fluorescence is emitted by Chi d indicating efficient energy transfer between antenna Chi d molecules and the unknown primary electron donor of PS II. P740 a reaction center Chl of PS I of A. marina is shown to give a dimer type cation, and triplet state with a D value of 245xlO$\^$-4/ cm$\^$-l/ in contrast to the 280-290 xlO$\^$-4/cm$\^$-l/ values of P700 suggesting triplet spins interacting at a 5% larger distance in P740 than in P700.

• Korean Chemical Engineering Research
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• 제50권5호
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• pp.913-922
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• 2012

환경 및 화학공업에서 액-액 교반조내의 특성을 파악하는 일은 매우 중요하다. 액적 부근의 물질이동용량계수 $k_La$와 Sauter 평균경 $d_{32}$은 에스테르의 알칼리 가수분해반응을 이용하여 임펠러 부착위치나 액높이를 변화시켜 측정하였다. 그 결과 아래와 같은 이들의 양호한 상관식을 얻었다. $$d_{32}=0.270\(\frac{{\sigma}^{0.6}}{{\rho}^{0.2}P^{0.4}_{Vi}}\)k_La=0.49\(\frac{6{\phi}D_A}{d^2_{32}}\)\(\frac{P_Vd^4_{32}}{{\rho}v^3}\)^{0.193}Sc^{1/3}$$.

• 한국항공운항학회지
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• 제12권3호
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• pp.25-39
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• 2004

An experimental study was quantitatively carried out in order to investigate the influence of flow conditions on a boundary layer in the near-wake of a flat plate. Tripping wires attached at various positions were selected to change flow conditions of a boundary layer in the vicinity of trailing edge. The flows such as laminar, transitional, and turbulent boundary layer at 0.98C from the leading edge are imposed to investigate the evolution of symmetric and asymmetric wake. Measurements were made at freestream velocity of 6.0m/s, and the corresponding Reynolds number is $2.8{\times}10^5$. An x-type hot-wire probe(55P61) was employed to measure at 8 stations in the near-wake region. Test results show that the near-wake of the flat plate for the case of a laminar and transitional boundary layer is sensitive to mean flow shear generated after separation but for the case of turbulent boundary layer is insensitive.

• Bulletin of the Korean Chemical Society
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• 제4권2호
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• pp.68-72
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• 1983

The $pK_{a}$ of $-NH_{3}^{+}$ group of chitosan in water was 6.2, while that of D-glucosamine-HCl, monomer of chitosan, was found to be 7.8. The difference of $pK_{a}$ values between chitosan and D-glucosamine was attributed to the strong electrostatic interaction between $-NH_{3}^{+}$ groups in chitosan. The apparent binding constant of $Cu^{2+}$ to D-glucosamine was estimated to be $1{\times}10^{4}$. For chitosan, no significant binding of $Cu^{2+}$ to the polymer was observed when pH < 5, but strong cooperative binding was observed near pH 5.1. The mechanism of such cooperativity was proposcd. Chitosan in solution exhibited typical polyelectrolytic behaviors: viscosity increases with increased amount of charged group, and decreases with addition of salt. The concentration dependence of viscosity was measured, and the Huggins parameters and intrinsic viscosity were calculated at various ionic strength. The results were interpreted in terms of molecular properties of the chitosan molecule.

• 한국전기전자재료학회논문지
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• 제28권2호
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• pp.99-103
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• 2015

One-dimensional photonic crystals (1D PCs) were fabricated by RF sputtering technique on p-Si (100), and fused quartz substrates. The 1D PCs structures consisted of $TeO_x$ (x=1.42), and $SiO_2$ with the difference refractive index. In order to estimate the effect on a defect level within 1D PCs structures, samples were prepared with both normal, and defect mode. The structural and optical properties were confirmed by Scanning electron microscope (SEM), and Ultraviolet visible near-infrared spectrophotometer (UV-VIS-NIR) respectively. In the case of a 1D PC normal mode without defect layer, it had a photonic band gap (PBG) in the near infrared (NIR) region. In the case of a 1D PC defect mode with defect layer, it had a sharp transmission band owing to a defect level, and moved towards the longer wavelength after exposing He-Cd laser with a wavelength of 325 nm.