• Title/Summary/Keyword: 준 가시선

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EIRP Measurements of WCDMA Base Station Using Pilot Channel in Line-of-Sight Environments (가시선 환경에서 Pilot 채널을 이용한 WCDMA 기지국의 EIRP 측정)

  • Jang, Byung-Jun;Moon, Sung-Won;Lim, Jae-Bong
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.22 no.5
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    • pp.545-551
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    • 2011
  • In this paper, we described a measurement method of an EIRP(Effective Isotropic Radiated Power) of a WCDMA base station using a pilot channel in line-of-sight environments. Especially we measured it in real base station environments in order to apply this method to domestic base station inspection test. Estimated EIRP results from measured value is -2 dB lower than theoretical values, which is calculated by the data of transmit antenna. The deviation of -2 dB is verified as a polarization mismatch between the base station antenna and a receiver antenna, and it can be calibrated. Therefore, we verified that our measurement method could be an effective tool to measure an EIRP in WCDMA base station inspection test.

A Study on Preventive Diagnosis of the Pole Transformer by Gas Analysis -Measurement of Aging of Insulating Oil by UV-Visible Spectrophotometric Method- (개스분석에 의한 주상변압기의 예방진단에 관한 연구 -자외-가시선 흡수분광광도법에 의한 절연유의 열화도 측정-)

  • 곽희로;남영우;윤영자;남궁미옥;이동준
    • The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.10 no.5
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    • pp.94-100
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    • 1996
  • Criteria for insulating oil condition of pole transformer were suggested by applying the UV-Visible spectrophotometric method. Aging of insulating oil caused the change in absorbances of oil as well as the deterioration of electrical properties of oil. By comparing the electrical properties such as tan$\delta$ and dielectric breakdown voltage with the UV-Visible absorbances of oil, following criteria for absorbance values determining oil condition were established, fair condition is below 0.580, need attention is 0.580-0.900 and poor condition is above 0.900. This W-Visible spectrophotometric method may be applied in aging analysis of oil and expected to replace the current visual method. It is necessary to develop cheap, light and portable UV-Visible spectrophotometer in near future for field application.

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A Study on the Strength Enhancement of Wale in Temporary Retaining Structures (흙막이 지하 가시설 구조체의 띠장 휨 강성 증대를 위한 연구)

  • Lim, Dong Hwan;Lee, Yong Jun;Ahn, Sang Ro
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.29 no.3C
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    • pp.91-96
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    • 2009
  • The purpose of this study was to investigate a method for the strength enhancement of wale in temporary retaining structures. Tests on the wale structures strengthened with carbon fibre reinforced plastic (CFRP) strips and prestressed with seven wire strands were conducted. From this test, it is found that the flexural stiffness and strength of the wales strengthened with CFRP strips and seven wire strands were significantly improved compared to the unstrengthened one. The ultimate tensile strains of attached CFRP strips on the steel beam were in the range of 8,000 and $11,000{\mu}{\epsilon}$, and it is noticed that the bonding ability with steel and CFRP strips is good. In this paper, a new method for enhancing the strength of wale in retaining structures is suggested.

Content-based Trademark Image Retrieval System using SOM (SOM을 이용한 등록상표에 대한 내용기반 이미지 검색)

  • Lee, Jae-Jun;Shin, Min-Ki;Paik, Woo-Jin;Shin, Moon-Sun
    • Annual Conference of KIPS
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    • 2007.05a
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    • pp.489-492
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    • 2007
  • 산업재산권중 하나인 상표에 대한 효율적인 이미지 검색은 상표도용 및 이로 인한 분쟁을 방지할 수 있다. 이를 위해서는 효율적인 내용기반 유사이미지 검색이 필요하다. 본 논문에서는 상표이미지검색에 있어 가시적인 특성(visual feature)을 그레이 히스토그램을 통해서 상표이미지의 특성값을 추출하여 이를 입력패턴으로 SOM(Self-Organizing Map)알고리즘을 적용한 내용기반 유사이미지 검색시스템을 제안한다.

A Study on the Characteristics of High Energy Nitrogen ion Implanted CdS Thin Films (고에너지 질소 이온 주입된 CdS 박막 특성에 관한 연구)

  • 이재형;홍석주;양계준
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.4
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    • pp.712-718
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    • 2003
  • The effects of nitrogen ion implantation on vacuum evaporated cadmium sulphide (CdS) thin films were investigated by X-ray diffraction, optical transmittance spectra, and Raman scattering studies. The as-deposited CdS films have a hexagonal structure with preferential (0 0 2) orientation. Formation of Cd metallic clusters was observed in ion implanted films from the XRD patterns. The band gap of N+ implanted films decreased, whereas the optical absorption coefficient values increased with the increase of implantation dose. The Raman peak position appeared at 299 cm-1 and the FWHM increased with the ion dose. A decrease in the area of Raman peak of CdS Al(LO) mode is seen on implantation.

Multipurpose Watermarking Scheme Based on Contourlet Transform (컨투어렛 변환 기반의 다중 워터마킹 기법)

  • Kim, Ji-Hoon;Lee, Suk-Hwan;Park, Seung-Seob;Kim, Ji-Hong;Oh, Sei-Woong;Seo, Yong-Su;Kwon, Ki-Ryong
    • Journal of Korea Multimedia Society
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    • v.12 no.7
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    • pp.929-940
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    • 2009
  • This paper presents multipurpose watermarking scheme in coutourlet transform domain for copyright protection, authentication and transform detection. Since contourlet transform can detect more multi direction edge and smooth contour than wavelet transform, the proposed scheme embeds multi watermarks in contourlet domain based on 4-level Laplacian pyramid and 2-level directional filter bank. In the first stage of the robust watermarking scheme for copyright protection, we generates the sequence of circle patterns according to watermark bits and projects these patterns into the average of magnitude coefficients of high frequency directional subbands. Then the watermark bit is embedded into variance distribution of the projected magnitude coefficients. In the second stage that is the semi-fragile watermarking scheme for authentication and transform detection, we embed the binary watermark image in the low frequency subband of higher level by using adaptive quantization modulation scheme. From the evaluation experiment using Checkmark 2.1, we verified that the proposed scheme is superior to the conventional scheme in a view of the robustness and the invisibility.

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An Analysis of Agenda-setting Process to Appoint Library Professional as the Director of National Assembly Library: Based on the Kingdon's Multiple Streams Model (국회도서관장 전문가 임명 정책 의제화 과정 분석 - Kingdon의 다중흐름모형을 적용하여 -)

  • Yeon, Jieun;Kim, Giyeong
    • Journal of the Korean Society for Library and Information Science
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    • v.51 no.3
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    • pp.293-322
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    • 2017
  • The purpose of the study is to identify the background of the agenda-setting to appoint library professional as the director of National Assembly Library and characteristics of the policy entrepreneur of this agenda. To this purpose an agenda-setting process in 2014 is analyzed with the Kingdon's multiple streams model. Kingdon's multiple streams model explains that an agenda is set when a window of opportunity is opened by coupling of problem stream, political stream, and policy stream. They have existed independently before setting the agenda. This study showed that the political stream was the major stream to open the window of opportunity. The lawmaker in the opposition party is identified as the leader for the agenda and the motivations, resources, and strategies of the policy entrepreneur were also analyzed. The analysis showed the agenda for library professional as the director was set without visible participation of library professionals. Therefore this study proposed the library professionals' roles for the library and information policy making process.

Synthesis and Photopolymerization of Discotic Liquid Crystals Containing Hydrogen Bondings and Two Polymerizable Groups (두 종류의 중합기와 수소결합을 가지는 원반형 액정의 합성과 광중합)

  • Lee Jun-Hyup;Lee Seung-Jun;Jang Ji-Sun;Jho Jae-Young
    • Polymer(Korea)
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    • v.30 no.5
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    • pp.373-379
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    • 2006
  • Polymerizable discotic liquid crystals containing diacetylene and acryloyl groups were formed through hydrogen bonding between phloroglucinol core and polymerizable pyridine derivatives, and their photopolymerization behavior was investigated. The discotic complexes exhibited discotic columnar and rectangular columnar mesophases depending on the number of aromatic rings. Photopolymerization of the discotic complexes was carried out by UV irradiation in the liquid crystalline state. IR and UV-Vis spectroscopy affirmed that diacetylene and acryloyl groups were selectively Polymerized, and that crosslinked polymers containing short conjugated diacetylene oligomers were produced by 1,4-addition. X-ray diffraction experiment showed that the columnar order in the discotic complex containing phenyl-pyridine moiety was maintained after photopolymerization, and that the rectangular columnar order in he discotic Complex with biphenyl units was changed to the lamellar order.

Tectonic Movement in the Korean Peninsula (I): The Spatial Distribution of Tectonic Movement Identified by Terrain Analyses (한반도의 지반운동 ( I ): DEM 분석을 통한 지반운동의 공간적 분포 규명)

  • Park, Soo-Jin
    • Journal of the Korean Geographical Society
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    • v.42 no.3 s.120
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    • pp.368-387
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    • 2007
  • In order to explain geomorphological characteristics of the Korean Peninsula, it is necessary to understand the spatial distribution of tectonic movements and its causes. Even though geomorphological elements which might have been formed by tectonic movements(e.g. tilted overall landform, erosion surface, river terrace, marine terraces, etc.) have long been considered as main geomorphological research topics in Korea, the knowledge on the spatial distribution of tectonic movement is still limited. This research aims to identify the spatial distributions of tectonic movement via sequential analyses of Digital Elevation Model(DEM). This paper first developed a set of terrain analysis techniques derived from theoretical interrelationships between tectonic uplifts and landsurface denudation processes. The terrain analyses used in this research assume that elevations along major drainage basin divides might preserve original landsurfaces(psuedo-landsuface) that were formed by tectonic movement with relatively little influence by denudation processes. Psuedo-landsurfaces derived from a DEM show clear spatial distribution patterns with distinct directional alignments. Lines connecting psuedo-landsufaces in a certain direction are defined as psuedo-landsurface axes, which are again categorized into two groups: the first is uplift psuedo-landsurface axes that indicate the axis of landmass uplift; and the second is denudational psuedo-landsurface axes that cross step-shaped pusedo-landsurfaces formed via surface denudation. In total, 13 axes of pusedo-landsurface are identified in the Korean Peninsula, which show distinct direction, length, and relative uplift rate. Judging from the distribution of psudo-landsurfaces and their axes, it is concluded that the Korean Peninsula ran be divided into four tectonic regions, which are named as the Northern Tectonic Region, Center Tectonic Region, Southern Tectonic Region, and East Sea Tectonic Region, respectively. The Northern Tectonic Region had experienced a regional uplift centered at the Kaema plateau, and the rate of uplift gradually decreased toward southern, western and eastern directions. The Center Tectonic Region shows an arch-shaped uplift. Its uplift rate is the highest along the East Sea and the rate decreases towards the Yellow sea. The Southern Tectonic Region shows an asymmetric uplift centered a line connecting Dukyu and Jiri Mountains in the middle of the region. The eastern side of the Southern Regions shows higher uplift rate than that of the western side. The East Sea Tectonic Region includes south-eastern coastal area of the peninsula and Gilju-Myeongchun Jigudae, which shows relatively recent tectonic movements in Korea. Since this research visualizes the spatial heterogeneity of long-term tenonic movement in the Korean peninsula, this would provide valuable basic information on long-term and regional differences of geomorphological evolutionary processes and regional geomorphological differences of the Korean Peninsula.

An Evaluative Study on the Content-based Trademark Image Retrieval System Based on Self Organizing Map(SOM) Algorithm (Self Organizing Map(SOM) 알고리즘을 이용한 상표의 내용기반 이미지검색 성능평가에 관한 연구)

  • Paik, Woo-Jin;Lee, Jae-Joon;Shin, Min-Ki;Lee, Eui-Gun;Ham, Eun-Mi;Shin, Moon-Sun
    • Journal of the Korean Society for information Management
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    • v.24 no.3
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    • pp.321-341
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    • 2007
  • It will be possible to prevent the infringement of the trademarks and the insueing disputes regarding the originality of the trademarks by using an efficient content-based trademark image retrieval system. In this paper, we describe a content-based image retrieval system using the Self Organizing Map(SOM) algorithm. The SOM algorithm utilizes the visual features, which were derived from the gray histogram representation of the images. In addition, we made the objective effectiveness evaluation possible by coming up with a quantitative measure to gauge the effectiveness of the content-based image retrieval system.