• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 The Korea-Japan Joint Symposium
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• pp.17-18
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• 2003

Swelling behaviors of Lyocell and Polynosic fibers are investigated by measuring fiber sizes in ferric sodium tartrate complex (FeTNa) and NaOH solution. They showed an anisotropic swelling behavior, i.e., a large expansion in a radius and small shrinking in a longitudinal direction. Birefringent structure was maintained in Lyocell fibers in the swollen state but not in Polynosic fibers for both solvent systems.

• 대한수학회지
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• 제37권6호
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• pp.929-941
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• 2000

We study a parabolic system of chemotaxis introduced by E.F. Keler and L.A. Segel. First, norm behaviors of the blow-up solution are proven. Then some kind of symmetry breaking and the concentration toward the boundary follow when the L$^1$norm of the initial value is less than 8$\pi$. Meanwhile a method of rearrangement is porposed toprove an inequality of Trudinger-Moser's type.

• 한국유변학회:학술대회논문집
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• 한국유변학회 2000년도 추계 학술발표회 논문집
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• pp.29-32
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• 2000

• International Journal of Control, Automation, and Systems
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• 제5권1호
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• pp.93-98
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• 2007

A class of new observers in descriptor linear systems, proportional-derivative(PD) observers, are proposed. A parametric design approach for such observers is proposed based on a complete parametric solution to the generalized Sylvester matrix equation. The approach provides complete parameterizations for all the observer gains, gives the parametric expression for the corresponding left eigenvector matrix of the observer system matrix, realizes elimination of impulsive behaviors, and guarantees the regularity of the observer system.

• 통합자연과학논문집
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• 제3권1호
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• pp.28-32
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• 2010

Thiophene-derivatized pentiptycenes were synthesized and characterized by NMR and UV-Vis spectroscopy. Aggregation behavior of thiophene-derivatized pentiptycenes was monitored by the measurement of fluorescence. Fluorescence intensities for the thiophene-derivatized pentiptycenes and thiophene-derivatized pentiptycenes aggregates were compared. There is no shift in the maximum of the emission wavelength. In the range of water fraction between 20% and 40%, the emission intensity of thiophene-derivatized pentiptycene aggregates remains almost identical. Fluorescence efficiency incresaed by about 5 times higher when the thiophene-derivatized pentiptycenes forms the aggregates in solution.

• 호남수학학술지
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• 제39권1호
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• pp.27-40
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• 2017

In this paper, we construct exact traveling wave solutions of various kind of partial differential equations arising in mathematical science by the system technique. Further, the $Painlev{\acute{e}}$ test is employed to investigate the integrability of the considered equations. In particular, we describe the behaviors of the obtained solutions under certain constraints.

• 진공이야기
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• 제4권4호
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• pp.14-17
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• 2017

Recently, quantum-dots light emitting diodes (QLEDs) are considered as a next-generation display due to the superior luminescence behaviors, photo stability and narrow spectral emission bandwidth. Moreover, the emission color of QLEDs can be easily controlled by changing the dimension of quantum dots (QDs). A flexible display based on QLEDs can be achieved using low-cost solution process, such as a printing technology. Therefore, QLEDs are expected as a next generation display. In this document, recent progresses in QDs technology will be introduced.

• 약학회지
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• 제22권2호
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• pp.83-86
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• 1978

A colorless sublime needles (A), $C_{10}H_{10}O_{4}$, mp$142~143\circ$ was isolated from the fresh flowers of Chrysanthemun sinense Sabine in 0.16% yield. Its ir, nmr and mass spectral data suggested that it may have an aromatic methylester structure. Hydrolysis of this substane with 10% sodium hydroxide solution yielded terephthalic acid and methanol. This substance was confirmed as dimethyl terephthalate by comparison of ir and nmr spectra, and TLC and GC behaviors of an authentic sample which was prepared from terephthalic acid by methylation. This is the first report that dimethly terephthalate was isolated in the Composite plants.

• 대한수학회지
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• 제56권5호
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• pp.1309-1331
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• 2019

We study the homogeneous Dirichlet boundary value problem of generalized Laplacian systems with a singular weight which may not be in $L^1$. Using the well-known fixed point theorem on cones, we obtain the multiplicity results of positive solutions under two different asymptotic behaviors of the nonlinearities at 0 and ${\infty}$. Furthermore, a global result of positive solutions for one special case with respect to a parameter is also obtained.

• 한국도서관정보학회지
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• 제53권3호
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• pp.263-285
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• 2022

본 연구에서는 중학생을 대상으로 중학생의 온라인 학습 행동에 영향을 미치는 새로운 요인을 구성하기 위한 요인분석을 제시하였다. 총 204명의 한국 중학생이 참여했으며, 중학교 3년 학생의 표본을 목적표본으로 선정하여 사용하였다. 요인 분석 결과는 공유 분산의 66.15%를 차지하는 35개 항목에 대한 8개 요인 솔루션을 제시했다. 중학생들의 온라인 학습 행동을 식별하기 위해 다양한 요인이 고려된다. 이때, 중학교 시기 온라인 러닝의 적절한 경험과 활용도는 그들의 미래 교육의 중요한 발판이 되기 때문에 중요하다. 본 연구의 결과는 중학생을 위한 온라인 러닝 시스템의 질을 향상시키고 온라인 학습을 발전시키기 위한 정보를 제공할 것으로 기대한다. 연구 결과는 중학생의 온라인 학습 행동에 영향을 미치는 8가지 중요한 요인을 제시했고, 그것들은 1) 소셜 미디어를 학습 도구로 활용한 커뮤니케이션, 2) ICT를 활용한 정보 공유 의지, 3) 테크놀러지 중독, 4) 테크놀러지 도입, 5) ICT를 활용한 정보 탐색, 6) 소셜 미디어 학습 활용, 7) ICT를 이용한 정보 검색, 그리고 8) 테크놀러지 몰입이다. 본 연구의 결과는 중학생들이 학습도구로 소셜미디어를 활용한 커뮤니케이션을 선호하며, ICT를 활용한 정보 공유 의도를 대부분 중시하고 있음을 확인하였다. 요인 분석을 기반으로 얻은 데이터는 온라인 러닝의 새로운 교육 플랫폼을 적용하기 위해, 소셜 미디어 학습과 ICT의 혼합에 대한 온라인 학습 행동에 중요하게 적용할 수 있을 것이다. 이 연구는 중학생들의 온라인 학습 행동을 더 잘 이해하고 온라인 학습 환경을 설계하는 정보 전문가가 특히 디지털 리터러시가 필요한 중학생에게 더 잘 지원할 수 있도록 유용하게 사용할 것으로 기대한다.