• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.311-311
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• 2006

The morphology of Poly(styrene-b-methylmethacrylate) (P(S-b-MMA)) block copolymer thin films deposited on silicon wafers was controlled by treating the substrates with Self-Assembled Monolayers (SAM) of phenylsilanes with different alkyl chain lengths. It was found that the treatment with SAM strongly modified the substrates properties, especillay the surface energy, as compared with bare silicon oxide. By futher adjusting the molecular weight of P(S-b-MMA), a variety of morphologies could be generated, including a perpendicular orientation of lamellea of PS and PMMA, which is required for industrial applications.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.2030-2035
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• 2005

In this paper, we study the distributed coordination of a set of synchronous, anonymous, memoryless mobile robots that can freely move on a two-dimensional plane but are unable to communicate directly. Based on this model, we analyze the application problem that consists in having a group of robots form a barricade line to protect from car traffic a crowd of demonstrators parading on the street. For the sake of robustness, we privilege fully decentralized solutions to the problem. In particular, we give a self-stabilizing distributed algorithm to address the problem, in this presentation

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.1606-1609
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• 2008

In this paper, we present a novel process for the realization of large area, low cost field emission cathodes. The process makes use of alumina substrates, which are anodically oxidized in order to yield porous structures capable of hosting metal catalyst nanoparticles. By carefully controlling the final stage of the anodisation as well as the electrodeposition conditions, it is possible to fine tune the density of such catalysts in the range of $10^8-10^9/cm^2$. The catalytic growth of CNTs is subsequently performed at low temperature (${\sim}\;600^{\circ}C$ or below, thanks to the use of $H_2O$), using plasma enhanced chemical vapour deposition. There is no lithography need to make the cathode and current densities of ${\sim}\;1mA/cm^2$ are easily obtained.

• Journal of Communications and Networks
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• 제12권6호
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• pp.533-543
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• 2010

This paper proposes an orthogonal frequency division multiplexing (OFDM) waveform for the forward link of a fixed broadband satellite system. We focus on the synchronization tasks in the receiver. Our objective is to minimize the required overhead, in order to improve the spectral efficiency with regard to a single carrier waveform system. A non pilot aided algorithm is used for fine synchronization. It is preceded by a coarse synchronization stage, which relies on a limited overhead (short cyclic prefix associated to some pilots). The performance of the proposed receiver is assessed through simulation results.

• 천문학회보
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• 제42권2호
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• pp.71.4-72
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• 2017

국립청소년우주센터에서 캄보디아의 Xavier Jesuit School과 연계하여 지역 중등교사 18명을 대상으로 천문교육을 지원했다. 이번 교육지원은 한국천문학회 소속 천문교육프로그램지원단과 캄보디아와의 교류를 통해 이루어졌다. 2017년 4월 3일부터 7일까지 5일 동안 시간과 좌표, 간이 망원경 제작, 결상의 원리, 분광, 망원경의 조립과 분해 및 천체관측 등 천체관측과 관련된 내용을 위주로 교육을 진행하였다. 이번 천문교육을 계기로 지속적인 천문교육지원이 이뤄지길 바라며, 이를 통해 캄보디아를 비롯해 천문교육이 제대로 이루어지지 못하는 지역의 청소년이 우주에 관심을 가지고 자신의 꿈을 펼칠 수 있게 되길 기대한다.

• 식물분류학회지
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• 제43권2호
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• pp.103-105
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• 2013

베트남에서 발견된 Capparis sikkimensis Kurz subsp. Masaikai (H. L$\acute{e}$v.) Jacobs 를 베트남 미기록 분류군으로 보고하고 분류학적 처리 및 식별을 위한 도해를 첨부하였다.

• Advances in materials Research
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• 제2권3호
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• pp.173-180
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• 2013

Lead-free complex perovskite ceramics $NaMeO_3$ ($Me{\equiv}Nb$, Ta) were synthesized using conventional solid state reaction technique and characterized by structural, FTIR and electrical (dielectric and ac conductivity) studies. The crystal symmetry, space group and unit cell dimensions were determined from the experimental results using FullProf software. XRD analysis of the compound indicated the formation of single-phase orthorhombic structure with the space group Pmmm (47). Dielectric studies showed the diffuse phase transition at $394^{\circ}C$ for $NaNbO_3$ and $430^{\circ}C$ for $NaTaO_3$. Ac conductivity in both the compounds follows Jonscher's power law.

• ALGAE
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• 제20권3호
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• pp.225-232
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• 2005

Optical microscopy of recently living and cleared material of the fucoid, Ascophyllum nodosum (L.) Le Jolis, revealed novel aspects of its interaction with the ascomycete Mycophycias ascophylli (Cotton) Kohlmeyer and Kohlmeyer (previously Mycosphaerella ascophylli Cotton). Most host cells are associated with hyphae by lateral attachment of cell walls. Hyphae form extensive networks throughout the host thallus and show considerable differentiation in the various host tissues. In the base of epidermal cells, hyphae form multicellular rings around each host cell to produce a continuous network. In medullary regions, long, relatively unbranched and longitudinally aligned hyphae occur, with radial branches extending into cortical regions. Scattered in the inner cortex of host tissue are numerous multicellular nodes of smaller, polygonal to irregular shaped cells with five or more radiating arms of hyphae. Individual hyphal cells show a variety of specializations including swellings and appressoria-like attachments to some host cells. These observations provide the morphological basis for the mutualistic symbiosis supported by recent experimental work. We conclude that this association is best described by the term “symbiotum.”

• ALGAE
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• 제20권3호
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• pp.233-238
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• 2005

The photosynthetic parameters of dark- adapted minimum fluorescence (Fo) and maximum quantum yield of charge separation in PSII (Fv/Fm) were measured in transverse sections of eight species of marine Phaeophyceae (species of Laminariales, Fucales, Desmarestiales, Chordariales) using pulse amplified modulation (PAM) fluorometry. Within each transverse section fluorescence was measured in three regions corresponding to outer cortical and meristoderm cells, inner cortical cells and innermost medullary cells. Minimum fluorescence declined from 19-74% (mean of 39%) from outermost to innermost cells. Maximum quantum yield varied from 0.51-0.59 in outermost cell layers and this was reduced to 0.23-0.40 in innermost cell layers, with an average reduction of 50%. Despite the reduction Fo in medullary cells (inner), medullas of all species showed maximum quantum yields consistent with a photosynthetic role in carbon fixation. These results show that medullary cells of complex brown algae have more than a role in structure, storage or transport, and may also provide an important role in carbon fixation.

• 한국멀티미디어학회논문지
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• 제21권4호
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• pp.441-449
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• 2018

Deep learning has been used for various processing centered on image recognition. One core algorithms of the deep learning, convolutional neural network is an deep neural network that specialized in image recognition. In this paper, we use a convolutional neural network to classify forest insects and propose an optimization method. Experiments were carried out by combining two weight initialization and six parameter update methods. As a result, the Xavier-SGD method showed the highest performance with an accuracy of 82.53% in the 12 different combinations of experiments. Through this, the latest learning algorithms, which complement the disadvantages of the previous parameter update method, we conclude that it can not lead to higher performance than existing methods in all application environments.