• Journal of Information Display
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• v.1 no.1
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• pp.3-8
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• 2000

We have developed a high performance vertical alignment TFT-LCD (Thin Film Transistor Liquid Crystal Display), that shows a high light transmittance, and wide viewing angle characteristics with an unusually high contrast ratio. In order to optimize the electro-optical properties we have studied the effect of cell parameters, multi-domain structure and retardation film compensation. With the optimized cell parameters and process conditions, we have achieved a 24" wide UXGA TFTLCD monitor (16:10 aspect ratio 1920X1200) showing a contrast ratio of over 500:1, panel transmittance near 4.5%, response time near 25 ms, and viewing angle higher than 80 degree in all directions.

• Proceedings of the KIEE Conference
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• summer
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• pp.683-685
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• 2004

This paper introduces a basic design for the short-term load forecasting system using a commercial data base. The proposed system uses a hybrid load forecasting method using fuzzy linear regression for forecasting of weekends and Monday and general exponential smoothing for forecasting of weekdays. The temperature sensitive is used to improve the accuracy of the load forecasting during the summer season. MS-SQL Sever has been used a commercial data base for the proposed system and the database is operated by ADO(ActiveX Data Objects) and RDO(Remote Data Object). Database has been constructed by altering the historical load data for the past 38 years. The weather iDormation is included in the database. The developed short-term load forecasting system is developed as a user friendly system based on GUI(Graphical User interface) using MFC(Microsoft Foundation Class). Test results show that the developed system efficiently performs short-term load forecasting.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2467-2472
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• 2010

Twenty novel tetramic acid derivatives (E)-3-(1-(alkyloxyamino)ethylidene)-1-alkylpyrrolidine-2,4-diones were synthesized by the reaction of 3-(1-hydroxyethylidene)pyrrolidine-2,4-diones with O-alkyl hydroxylamines. The title compounds were confirmed by IR, $^1H$ NMR, MS and elemental analysis. The structure of compound 6r was further verified by X-ray diffraction crystallography. The bioassays showed that most of the title compounds exhibited noticeable herbicidal and fungicidal activities.

• Journal of Korea Multimedia Society
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• v.20 no.4
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• pp.606-613
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• 2017

When the planar area is captured by the depth camera, the shape of the plane in the captured image has perspective projection distortion according to the position of the camera. We can correct the distorted image by the depth information in the plane in the captured area. Previous depth information based perspective distortion correction methods fail to satisfy the real-time property due to a large amount of computation. In this paper, we propose the method of applying the conversion table selectively by measuring the motion of the plane and performing the correction process by parallel processing for correcting perspective projection distortion. By appling the proposed method, the system for correcting perspective projection distortion correct the distorted image, whose resolution is 640x480, as 22.52ms per frame, so the proposed system satisfies the real-time property.

• Natural Product Sciences
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• v.9 no.3
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• pp.174-176
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• 2003

Studies on the stem bark extracts of Garcinia cuneifolia have furnished a new xanthone cuneifolin (1) and the triterpene stigmasterol (2). Structures for these compounds were elucidated based on NMR, 2D NMR, MS and GCMS data. Larvicidal activity screening of the crude bark extract using the larvae of Aedes aegypti indicated the larvae to be susceptible to these extracts. $LC_{50}$ values of the bioassays show the extracts to be moderately toxic to the larvae of Aedes aegypti.

• Bulletin of the Korean Chemical Society
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• v.25 no.8
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• pp.1207-1210
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• 2004

Holmium $\beta$ -diketonate complexes, Ho(hfa)$_3$(tme), has been prepared and characterized by IR, TGA, MS, and single-crystal X-ray analyses. This complex is air- and moisture-stable and most importantly has good volatility and thermal stability. Holmium atom binds to nine oxygen atoms, contributed by six oxygen atoms of three hfa ligands and three oxygen atoms of the tme ligand. The coordination polyhedron of Ho can be described as a distorted tricapped trigonal prism. Crystal data for $Ho(hfa)_3(tme)$; orthorhombic $P2_12_12_1$, a = 15.415(4), b = 13.17(2), c = 17.291(3) $\AA$, V = 3496(1) ${\AA}^3$.

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1515-1518
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• 2010

Regio- and diastereoselective 1,3-dipolar cycloaddition reactions of nitrones {(Z)-${\alpha}$-phenyl-N-methylnitrone (1a) and (Z)-${\alpha}$-propyl-N-butylnitrone (1b)} with electron-deficient perfluoro-2-methyl-2-pentene (2) lead to novel isoxazolidines {5-fluoro-5-pentafluoroethyl-4,4-bis-trifluoromethyl-2-methyl-3-phenyl-isoxazolidine (3a) and 2-butyl-5-fluoro-5-pentafluoroethyl-4,4-bis-trifluoromethyl-3-propyl-isoxazolidines (3b) respectively} as major constituents. These derivatives were characterized by IR, $^1H$ and $^{19}F$ NMR, GC-MS and NOE measurements, and the absolute structure of 3a was confirmed by X-ray crystallography.

• Annual Conference of KIPS
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• 2002.04a
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• pp.569-572
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• 2002

한글을 인식하기 위한 전처리 방법으로 흔히 모음의 종류 및 자음과의 결합 정도에 따라 6가지 유형으로 분류하는 방법을 많이 사용하고 있다. 간 논문에서는 이러한 한글 문자를 인식하기 위한 전처리 과정으로써 한글의 유형을 분류하는 방법에 대한 연구로 계층적인 신경회로망을 도입하여 빠르고 신뢰성 있는 분류 방법을 제안한다. 실험에 사용된 글자는 KS X 1001(KS C 5601) 완성형 글자 2,350개에 대한 굴림, 바탕, 돋움, 궁서 글꼴로 총 9400개의 이미지 파일을 사용하였으며. 이 중 일부는 훈련에 사용하고 나머지는 분류를 위한 테스트 데이터로 사용한 결과 약 94%의 유형 분류율과 개별 패턴을 5.67ms에 분류하는 빠른 분류 속도를 나타내었다.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.05a
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• pp.50.1-50.1
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• 2009

셀룰로오스를 Ca(OH)2와 Ni(OH)2를 Pot에 넣고 동시에 밀링 공정을 실시한 후, 열을 가함으로써 수소를 얻었다. X-ray diffraction (XRD), thermogravimetry/ mass spectrometry (TG/MS), gas chromatography (GC) 장비를 이용해 수소 발생량 및 촉매의 역할에 관하여 실험하였다. 촉매 Ni(OH)2를 대신한 NiO 또는 Ni를 사용했을 경우 사용된 촉매에 따른 수소의 발생량의 차이를 보였는데 이는 촉매의 사이즈가 수소 발생량과 관련이 있음을 보여주었다. 한편, Ca(OH)2를 대신하여 Li(OH)를 사용하였을 때 수소 발생 온도가 약$400\sim500\;^{\circ}C$ 범위에서 $350\sim400\;^{\circ}C$의 범위로 낮아져 보다 낮은 온도에서 수소 회수가 가능하였다. 이때 발생한 CO와 CO2는 수 ppm정도로 적은 양이었다.

• Information and Communications Magazine
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• v.24 no.12
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• pp.65-73
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• 2007

2007년8월 v2.0을 출간하면서 표준화가 완료된 Ultra Mobile Broadband(UMB) 기술은 진보된 안테나 기술과 함께, CDMA, TDM, Layer-superposed OFDM(LS-OFDM), OFDM, OFDMA의 장점들을 하나의 Air Interface로 통합하였으며, 효율적인 자원 관리 기법을 통해 더 많은 VoIP 사용자들을 수용할 수 있게 해준다. 4x4 안테나를 사용시 20MHz의 주파수 대역에 순방향 288 Mbps, 역방향 75 Mbps의 최대 전송률을 제공하며, 양방향에 대한 평균 Network 지연시간은 약 16.8 ms을 지원하고, 10 MHz 주파수 대역에 1000명 이상의 VoIP 사용자를 지원할 수 있다. 본 고에서는 UMB의 표준화 과정 및 현황 그리고 물리 계층과 MAC 계층의 요소 기술들에 대해 고찰한다.