• 호남수학학술지
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• 제24권1호
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• pp.35-41
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• 2002

The solutions of a homogeneous system in state space form $\dot{x}=Ax$ are to the form $x=e^{At}x_0$ and the solutions of an inhomogeneous system $\dot{x}=Ax(t)+f(t)$ are to the form $x=e^{At}x_0+{{\int}_0^t}\;e^{A(t-{\tau})}f({\tau})d{\tau}$. In this note we show that the solution of descriptor systems under some conditions exists, and is unique, moreover it is interesting to know the solutions of descriptor system are schematically like the solutions as in the state space form. Also we will give some algorithms to compute these solutions.

• 대한한방소아과학회지
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• 제30권2호
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• pp.96-106
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• 2016

Objectives The purpose of this study is to investigate the effects of Gleditsiae Fructus 70% EtOH extract (JS_E) on anti-inflammatory action in HaCaT cells (A spontaneously immortalized human keratinocyte cell line) and inhibiting triglyceride genesis in SEB-1 cells (Immortalized human sebocyte). Methods The anti-inflammatory effect of JS_E was analyzed by enzyme-linked immunosorbent assays (ELISA) which measured levels of IP-10, RANTES and MDC in HaCaT cells. Also the effect on secretion of sebum of JS_E was analyzed by TG-S kit which measured the quantity of triglyceride in SEB-1 cells. Results JS_E inhibited IP-10, RANTES and MDC expression in a dose dependent manner. IP-10 expression was inhibited significantly in comparison to TNF-${\alpha}$ and IFN-${\gamma}$ recombination (TI) control group at concentration of JS_E $200{\mu}g/ml$ and RANTES and MDC expressions were inhibited significantly at concentration of JS_E 100, $200{\mu}g/ml$. JS_E also inhibited triglyceride secretion of SEB-1 cells significantly in comparison to the control group in a dose dependent manner. Conclusions This study shows that JS_E has the effects of anti-inflammatory action and inhibiting sebum secretion. According to these results, JS_E can be used for treating skin diseases such as acne and dermatitis caused by inflammation and excessive secretion of sebum by controlling the activity of the HaCaT and SEB-1 cells.

• Imaging Science in Dentistry
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• 제43권4호
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• pp.245-251
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• 2013

Purpose: This study was performed to evaluate the relationship between anterior disc displacement and effusion in temporomandibular disorder (TMD) patients using magnetic resonance imaging (MRI). Materials and Methods: The study subjects included 253 TMD patients. MRI examinations were performed using a 1.5 T MRI scanner. T1- and T2-weighted images with para-sagittal and para-coronal images were obtained. According to the MRI findings, temporomandibular joint (TMJ) disc positions were divided into 3 subgroups: normal, anterior disc displacement with reduction (DWR), and anterior disc displacement without reduction (DWOR). The cases of effusion were divided into 4 groups: normal, mild (E1), moderate (E2), and marked effusion (E3). Statistical analysis was made by the Fisher's exact test using SPSS (version 12.0, SPSS Inc., Chicago, IL, USA). Results: The subjects consisted of 62 males and 191 females with a mean age of 28.5 years. Of the 253 patients, T1- and T2-weighted images revealed 34 (13.4%) normal, DWR in 103 (40.7%), and DWOR in 116 (45.9%) on the right side and 37 (14.6%) normal, DWR in 94 (37.2%), and DWOR in 122 (48.2%) joints on the left side. Also, T2-images revealed 82 (32.4%) normal, 78 (30.8%) E1, 51 (20.2%) E2, and 42 (16.6%) E3 joints on the right side and 79 (31.2%) normal, 85 (33.6%) E1, 57 (22.5%) E2, and 32 (12.7%) E3 on the left side. There was no difference between the right and left side. Conclusion: Anterior disc displacement was not related to the MRI findings of effusion in TMD patients (P>0.05).

• 방송공학회논문지
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• 제10권4호통권29호
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• pp.610-620
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• 2005

본 연구는 프로그램 연동형 T-Commerce 이용 의도에 영향을 미치는 소비자 수용 요인을 파악하기 위하여 지상파 양방향 디지털 방송에 노출된 시청자들을 대상으로 이들이 e-Commerce에 대해 지각하는 유용성 및 이용 용이성이 T-Commerce 이용 의도에 미치는 영향을 실증 분석하였다. 이 과정에서 사용자가 보유한 새로운 기술에 대한 혁신성이 유용성이나 이용 용이성과 이용 의도간의 관계를 조절하는 지에 대한 분석이 병행되었다. 분석 결과 양방향 매체를 대상으로 실시된 선행 연구들과 마찬가지로 지각된 유용성은 이용 의도에 유의한 영향을 미치는 반면 지각된 이용 용이성은 유의한 영향을 미치지 못하는 것으로 나타났다. 또한, 다른 양방향 매체들을 대상으로 실시된 기존의 연구 결과와는 달리 이용자의 혁신성이 지각된 유용성이 이용 의도에 미치는 영향을 조절하는 것으로 나타났다. 이러한 연구 결과를 통하여 T-Commerce의 시행 단계에 따라 시청자 유인 전략이 달라져야 한다는 시사점을 얻을 수 있었다.

• 한국수산과학회지
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• 제36권4호
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• pp.402-408
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• 2003

A quantitative method was suggested for estimating damages in fishery production due to the diffusion and deposition of suspended silt and clay by various construction processes in tidal flat fishing grounds. Marine populations are maintained through the process of spawning, growth, recruitment, natural death and death by fishing each year. All of the year classes of the population in a fishery ground could be affected when damages occur by human activities such as land filling or reclamation. The propose of this study is to calculate damages in terms of fishery production using a quantitative population dynamic method. If the maximum age in the population is $X_\lambda,$ the starting year of damage is $t_s,$ and the ending year of damage is $t_e,$ the number of year classes damaged is $t_{s-n\lambda}-t_e,$ Many year classes present in the year $t_s,$ and so if damages occur, they Influence all the year classes which are present in the population. Damaged year classes in year $t_e$ would still be in the population until the year $t_{e+n\lambda}$, where $n_{\lambda}$ is the oldest age class. If the expected yield of a year class is constant, the total yield from year classes in the fishing ground during the construction periods can be calculated as follows: $Y_\Phi=[(t_e-t_s+1)+n_c]{\cdot}Y_E+\sum\limits^{n_\lambda-n_c}_{l=1}\;\sum\limits^{n_\lambda-n_c}_{l=i}\;Y_{n_c+i}$ This method was applied for damage estimation in the production of Ruditapes philippinarum in a tidal flat fishing ground.

• 미생물학회지
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• 제53권4호
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• pp.351-353
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• 2017

토마토 뿌리에서 분리한 Chryseobacterium sp. T16E-39 균주는 식물생육촉진과 역병, 시들음병에 대한 억제효과가 있었다. 이 균주의 유전체 염기서열은 4,873,888 염기쌍이었으며 G + C 함량은 35.22%이었다. 이 유전체는 4,289개 단백질 유전자, 15개 rRNA 유전자, 71개 tRNA 유전자를 포함하였다. T16E-39 균주의 유전체에서 인산가용화, 식물호르몬 조절, 항산화 활성, 키틴 분해, 제9형 분비시스템에 관여하는 유전자를 확인하였으며, 이들 유전자는 식물의 생육을 촉진하고 병발생을 억제하는 기작과 관련되어 있을 것으로 판단된다.

• 한국정보통신학회논문지
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• 제9권1호
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• pp.188-198
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• 2005

부동소수점 제곱근 계산에 많이 사용하는 골드스미트 제곱근 알고리즘은 곱셈을 반복하여 제곱근을 계산한다. 본 논문에서는 골드스미트 제곱근 알고리즘의 반복 과정의 오차를 예측하여 오차가 정해진 값보다 작아지는 시점까지 반복 연산하는 알고리즘을 제안한다. 'F'의 제곱근 계산은 초기값 $X_0=Y_0=T^2{\times}F,\;T=\frac{1}{\sqrt {F}}+e_t$에 대하여, $R_i=\frac{3-e_r-X_i}{2},\;X_{i+1}=X_i{\times}R^2_i,\;Y_{i+1}=Y_i{\times}R_i,\;i{\in}\{{0,1,2,{\ldots},n-1} }}'$을 반복한다 곱셈 결과는 소수점 이하 p 비트 미만을 절삭하며, 절삭 오차는 $e_r=2^{-p}$보다 작다. p는 단정도실수에서 28, 배정도실수에서 58이다. $X_i=1{\pm}e_i$ 이면 $X_{i+1}$ = $1-e_{i+1}$ $e_{i+1} {\frac{3e^2_i}{4}{\mp}\frac{e^3_i}} $ +4$e_{r}$이다. $|X_i-1|$ < $2^{\frac{-p+2}{2}}$이면, $e_{i+1}$ < $8e_{r}$ 이 부동소수점으로 표현할 수 있는 최소값보다 작게 되며, $\sqrt{F}$ {\fallingdotseq}\frac{Y_{i+1}}{T}}$이다. 본 논문에서 제안한 알고리즘은 입력 값에 따라서 곱셈 횟수가 다르므로, 평균 곱셈 횟수를 계산하는 방식을 도출하고, 여러 크기의 근사 역수 제곱근 테이블 ($T=\frac{1}{\sqrt{F}}+e_i$)에서 단정도실수 및 배정도실수의 제곱근 계산에 필요한 평균 곱셈 횟수를 계산한다. 이들 평균 곱셈 횟수를 종래 알고리즘과 비교하여 본 논문에서 제안한 알고리즘의 우수성을 증명한다. 본 논문에서 제안한 알고리즘은 오차가 일정한 값보다 작아질 때까지만 반복하므로 제곱근 계산기의 성능을 높일 수 있다. 또한 최적의 근사 역수 제곱근 테이블을 구성할 수 있다. 본 논문의 연구 결과는 디지털 신호처리, 컴퓨터 그래픽스, 멀티미디어, 과학 기술 연산 등 부동소수점 계산기가 사용되는 분야에서 폭 넓게 사용될 수 있다.

• 생명과학회지
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• 제13권4호
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• pp.541-550
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• 2003

본 실험에서는 C형 간염바이러스 (HCV)의 외피 단백질인 E2 당단백질에 결합하는 세포단백질들을 클로닝하기 위해 간세포 cDNA를 phage 표면에 발현시킨 phage library를 제작하였고, 12-mer peptide library와 함께 E2 단백질에 대해 panning을 실시하였다. 검색결과 세포내 신호전달과 cytoskeleton 구성에 관여하는 tensin, membrane protein band 4.1 등 세포질내 단백질과 CCR7, CKR-L2, insulin-like growth factor-1 receptor 등 세포막 단백질 등이 확인되었다. 이들 단백질들을 발현하는 phage들은 수용성 E2단백질을 이용한 결합중화반응 결과 E2 단백질에 특이적으로 결합함이 확인되었다. 사람 T 세포에서 주로 발현되는 CCR7 유전자를 PHA로 활성화된 사람 T 세포의 total RNA를 이용하여 증폭하고 클로닝하였다. 293T 세포에 transfection시켜 단백질 발현양상을 flow cytometer로 분석하여 70% 이상의 세포들이 CCR7을 발현하고 있음을 관찰하였다. 수용성 E2 단백질을 CCR7이 transfection된 세포와 mock transfection된 대조군 세포에 각각 반응시킨 결과 dose-dependent 양상으로 CCR7에 결합하였다.

• 호남수학학술지
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• 제28권4호
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• pp.533-541
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• 2006

let E be a Finsler modules over $C^*$-algebras. A with norm-map $\rho$ and L(E) set of all A-linear bonded operators on E. We show that the canonical homomorphism ${\phi}:L(E){\rightarrow}L(E_I)$ sending each operator T to its restriction $T|E_I$ is injective if and only if I is an essential ideal in the underlying $C^*$-algebra A. We also show that $T{\in}L(E)$ is a bounded below if and only if ${\mid}{\mid}x{\mid}{\mid}={\mid}{\mid}{\rho}{\prime}(x){\mid}{\mid}$ is complete, where ${\rho}{\prime}(x)={\rho}(Tx)$ for all $x{\in}E$. Also, we give a necessary and sufficient condition for the equivalence of the norms generated by the norm map.

• 대한약리학회지
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• 제9권1호
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• pp.59-63
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• 1973

Although numerous drugs are available for the treatment of superficial fungi infections of skin, and yet the clinical effects of most of such drugs are not satisfactory. In the hope of searching for effective drugs for superficial fungi infections, the authors observed fungistatic effects of Pyrethri Flos, a common herb in Korea, with water extract (PFWE), ethanol extract (PFEE), and methanol extract (PFME) from Pyrethrum cinerariaefolium V. In in vitro studies, the spores of fungi were inoculated on Sabouraud's glucose agar media which contained Pyrethri Flos extracts in each concentrations of $500\;{\mu}g/ml$, $1,000\;{\mu}g/ml$ and $5,000\;{\mu}g/ml$ respectively, and the growth of the fungi was observed for 3 weeks. The species of the fungi used in these experiments were Epidermophyton floccosum, Microsporum canis, Microsporum nanum, Microsporum gypseum, Microsporum cookei, Trichophyton rubrum, Trichophyton mentagrophytes, Trichophyton tonsurans and Trichophyton verrucosum. The results of these studies were as follows; 1. The growth of M. nanum & T. rubrum was slightly inhibited by PFWE $500\;{\mu}g/ml$, and the growth of M. nanum, M. cookei & T. rubrum was slightly inhibited by PFWE $1,000\;{\mu}g/ml$. The growth of E. floccosum, M. gypseum & M. cookei was slightly inhibited, however the growth of M. canis, M. nanum, T. mentagrophytes, T. rubrum & T. tonsurans was significantly inhibited by PFWE $5,000\;{\mu}g/ml$. With $500\;{\mu}g/ml$ of PFEE, the growth of M. canis, M. nanum, T. mentagrophytes, T. rubrum & T. tonsurans was significantly inhibited, and moderate inhibition of M. cookei growth and slight inhibition E. floccosum & M. gypseum were observed. The growth of M. canis, M. nanum, T. mentagrophytes, T. rubrum & T. tonsurans was significantly inhibited, and the growth of E. floccosum, M. gypseum & M. cookei was moderately inhibited by PFEE $1,000\;{\mu}g/ml$. Significant inhibitions of the growth of E. floccosum, M. canis, M. nanum, M. gypseum, M. cookei, T. mentagrophytes, T. rubrum & T. tonsurans were observed by PFEE $5,000\;{\mu}g/ml$. 3. The growth of E. floccosum & M. cookei was moderately inhibited, and the growth of M. canis, M. nanum, M. gypseum, M. mentagrophytes, T. rubrum & T. tonsurans was significantly inhibited by PFME $500\;{\mu}g/ml$. But the growth of E. floccosum, M. canis, M. nanum, M. gypseum, M. cookei, T. mentagrophytes, T, rubrum & T. tonsurans was significantly inhibited, and the growth of T. verrucosum was slightly inhibited in both PFME $1,000\;{\mu}g/ml$ and $5,000\;{\mu}g/ml$.