• Title/Summary/Keyword: 가시장

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Low emission vehicles : their prospective engine technologies (저공해 엔진기술의 현황 및 방향)

  • 김창호
    • Journal of the korean Society of Automotive Engineers
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    • v.13 no.3
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    • pp.68-75
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    • 1991
  • 본 고에서는 배기가스 저감(특히 HC를 중심으로)에 대해 알려져 있는 기술들을 소개하고 가시적인 목표로 주어진 CARB의 저공해 차량에 적용 가능한 기술들을 예측해 보며 여러분야 전문가들의 열띤 토론의 장을 만들어 향후 엔진개발의 방향 설정에 기여해 보고자 한다. 여기서 논의의 범위를 승용차용 엔진으로 한정함을 첨언해 둔다.

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The Dissolution Efficiency of Gold Concentrate with Microwave-nitric Acid Leaching and the Recovery of Invisible Gold Using the Filter Paper (마이크로웨이브-질산용출에 의한 금 정광의 용해효율과 여과지를 이용한 비-가시성 금 회수)

  • Lee, Jong-Ju;Park, Cheon-Young
    • Economic and Environmental Geology
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    • v.52 no.6
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    • pp.595-604
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    • 2019
  • The purpose of this study was simply to obtain gold through a microwave-nitric acid experiment of invisible gold concentrate with the use of filter paper. For the purpose, this study conducted a microwave-nitric acid leaching experiment and examined nitric acid concentration. As a result of the experiment, this study discovered that Fe, Te and Ag were completely leached in the leaching solution whereas Au was not determined in all of the nitric acid conditions. The leaching solution was filtered with three filter papers and then these filter papers were analyzed with SEM/EDS. As a result of the EDS analysis, Au was detected in all of the surface and cross-section of the 1st, 2nd and 3rd filter papers. As the three filter papers containing solid-residue were analysed in the lead-fire assay, gold particles were found in all of the nitric acid conditions. In the lead-fire assay, maximum gold(452.50g/t) was recovered when nitric acid concentration was 6M and microwave leaching time was 12mins.

Experimentally Evaluating Fatigue Behavior of Corroded Steels Exposed in Atmospheric Environments (대기환경하에서 장기간 사용된 부식강재의 실험적 피로거동평가)

  • Mun, Jae Min;Jeong, Young Soo;Jeon, Je Hyeong;Ahn, Jin Hee;Kim, In Tae
    • Journal of Korean Society of Steel Construction
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    • v.29 no.3
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    • pp.193-204
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    • 2017
  • Fatigue strength of temporary steels and painted structural steels corroded under outdoor atmospheric environments is not clear. In this study, fatigue tests were carried out on steel plates which were cut off from 7-year-old temporary structural member under subway construction environment and from 75-year-old Yeongdo bridge member under marine atmospheric environment. After removing corrosion production on the steel surface, 3-dimensional surface geometry of the corroded steel was measured at intervals of $1.0{\times}1.0mm$, and corrosion characteristics such as minimum, maximum and mean values of residual thicknesses were calculated. From the fatigue test and FEM analysis results, the relationship between corrosion characteristics and fatigue behavior was presented, and change in fatigue strength of the unpainted and painted steels corroded in outdoor environments was also presented.

Performance Analysis of Wireless Communication Interface System Module Combined LED Light Device (LED조명 디바이스를 접목한 무선통신 인터페이스 시스템 모듈 성능 분석)

  • Jang, Tae-Soo;Lee, Jun-Myung;Park, Keon-Jun;Kim, Yong-Kab
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.11
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    • pp.2431-2436
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    • 2012
  • This paper is implemented simple visible light communication system by combining the communications through LED lighting. It uses a variable PD sensor to the receiver and 1~12 the LED light-emitting device to the transmitter to realize LED visible light communication. Initial distance value of the developed transmission and receiver is more than 0~1.5m for LED visible light communication, the overall system transmission rate is organized with thousands kbps variability visible light media transmission system. It was measured the performance experiment during lens wearing or not wearing in order to increase the overall efficiency of the LED module, configures the LED and PD to existing PC module for the performance analysis of the implemented research, experiments the maximum communication distance of the transmitter/receiver according to LED count and the transmission rate, check about application methods and the possibility.

A LED Light Communication Transceiver Module for Ubiquitous Sensor Networks (유비쿼터스 센서 네트워크용 LED 가시광통신 송수신 모듈 및 효율 연구)

  • Jang, Tae-Su;Kwon, Jae-Hyun;Kim, Yong-Kab;Park, Choon-Bae
    • The Journal of the Korea institute of electronic communication sciences
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    • v.7 no.6
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    • pp.1513-1518
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    • 2012
  • This paper is implemented media transmission system of VLC transmitter and receiver module using LED of White lighting that is based on PC module and to transmission technology for performance analysis. To realize LED visible light communication receiver is used 1~12 LED light-emitting device and transmitter is used a variable sensor. Developed initial distance of the tranceiver is more than 0~1m for LED VLC and the overall system transmission speed is achieved on variable having Visible light media transmission system. Composition to PC module with LED module and infrared sensor for performance analysis, predict and analyze the communication distance, check about the possibility of application methods. Measure each performance when the lens wearing and not wearing in order to increase the overall efficiency of the LED module, can know that increase efficiency of approximately 20%.

Multi-spectral Flash Imaging using Region-based Weight Map (영역기반 가중치 맵을 이용한 멀티스팩트럼 플래시 영상 획득)

  • Choi, Bong-Seok;Kim, Dae-Chul;Lee, Cheol-Hee;Ha, Yeong-Ho
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.9
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    • pp.127-135
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    • 2013
  • In order to acquire images in low-light environments, it is usually necessary to adopt long exposure times or resort to flash lights. However, flashes often induce color distortion, cause the red-eye effect and can be disturbing to subjects. On the other hand, long-exposure shots are susceptible to subject-motion, as well as motion-blur due to camera shake when performed hand-held. A recently introduced technique to overcome the limitations of traditional low-light photography is that of multi-spectral flash. Multi-spectral flash images are a combination of UV/IR and visible spectrum information. The general idea is that of retrieving details from the UV/IR spectrum and color from the visible spectrum. However, multi-spectral flash images themselves are subject to color distortion and noise. This works presents a method to compute multi-spectral flash images so that noise can be reduced and color accuracy improved. The proposed approach is a previously seen optimization method, improved by the introduction of a weight map used to discriminate uniform regions from detail regions. The weight map is generated by applying canny edge operator and it is applied to the optimization process for discriminating the weights in uniform region and edge. Accordingly, the weight of color information is increased in the uniform region and the detail region of weight is decreased in detail region. Therefore, the proposed method can be enhancing color reproduction and removing artifacts. The performance of the proposed method has been objectively evaluated using long-exposure shots as reference.

Optical design of three-mirror telescope system for infra-red and visible imaging (적외선 및 가시광선 결상용 3반사망원경계의 설계)

  • 이종웅;홍경희;권우근
    • Korean Journal of Optics and Photonics
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    • v.7 no.3
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    • pp.183-190
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    • 1996
  • To design three-mirror telescope system (F/8, 120 inch in focal length) for visible and infra-red band imaging, methods for power configuring and correction of the third order aberrations were studied. In the design of the telescope system, a three-mirror system corrected for spherical aberration, coma, and astigmatism was used for infra-red imaging, and the aberrations were corrected by using conic surfaces. For visible imaging, a singlet corrector lens was appended at the front of the focal plane to correct filed curvature. The telescope system has diffraction limited performance for 10 ${\mu}{\textrm}{m}$ in wavelength within 2.4$^{\circ}$ of field-of-view. In the visible band imaging, the rms spot size of the telescope system is less than 25 ${\mu}{\textrm}{m}$ within 3$^{\circ}$ of field-of-view for monochromatic light, and the telescope system satisfies flat field condition for CCD application.

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A Study on the Visitor's Visual Behavior and Isovist Area in Museum Exhibition Space - Focus on the Busan Museum, Gimhae National Museum - (박물관 전시공간에서의 관람자 시각행동과 가시영역에 관한 조사 연구 - 부산박물관, 국립김해박물관을 중심으로 -)

  • Yoo, Jae-Yub;Choi, Jun-Huck;Lim, Che-Zinn
    • Korean Institute of Interior Design Journal
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    • v.19 no.6
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    • pp.197-205
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    • 2010
  • For the spatial experience of spectators visiting a museum, the route search of trying to follow the spatial structure or production of exhibition and the information search of trying to see are accomplished at the same time. In such process, the spectator's reaction of visual perception produces the result of emotional reaction and action exchanged between human and space by going through the recognition and perception on the target of environment factor. For the spatial experience of a spectator, the reaction of visual perception which interacts according to the exhibit and exhibition environment within space according to viewing purpose, interest and concern of spectator comes out as visual activity which is an activity to understand the spatial information shown as various activities according to spatial structure and unfolding characteristics of the display. The purpose of this study is to identify The Correlation of Spectator Movement Created According to Structural Form of Exhibition Area Based on Interaction between Exhibition Area Structure and Spectator to utilize as basic material while designing museum exhibition using isovist field which is a quantitative analysis tool of spectator's visual behavior and spatial structure at each exhibition area.

Visual Measurement of Rotational Displacements by Using Two Different Moire Fringes Simultaneously Generated by Repeated Sinusoidal Gratings (반복사인격자에서 동시에 생기는 두 가지 무아레 무늬를 이용한 회전변위의 가시적 측정)

  • Jeong, Youn-Hong;Oh, Jeong-Hyo;Jo, Jae-Heung
    • Korean Journal of Optics and Photonics
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    • v.19 no.4
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    • pp.302-309
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    • 2008
  • We present the precise visual measurement method of rotational displacements using two different moire fringes simultaneously generated by repeated sinusoidal gratings. We investigate the variation of moire fringes depending on rotational displacements through computer simulation and experiment using a rotator in detail. The moire fringes are composed of the wide linear fringe part with a long period and the narrow linear fringe part with a short period. These parts are superior to the angle detection of more than 12 degrees and less than 12 degree, respectively. Additionally, the method can be visually used in the determination of the rotational direction by observing the moire fringe's direction.

Photocatalytic Degradation of Methyl-tertiary butyl ether using Element-Enhanced Photocatalyst

  • Yang, Chang-Hui;Sin, Myeong-Hui;Jang, Jong-Dae;Lee, Jin-U;Choe, Seong-Rak;Jo, Wan-Geun
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2008.11a
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    • pp.110-113
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    • 2008
  • 최근 가시광선에서 응답하는 광촉매를 이용하여 저농도의 일반적인 실내 대기 오염물질 제어를 위한 적용가능성에 대해 많은 평가가 있어왔다. 가시광선에서 활성을 보이는 질소 원소가 도핑된 TiO$_2$광촉매를 이용하여 대표적인 휘발성유기화합물질들 중에 하나인 MTBE의 분해율에 대한 실험을 실시하였다. 본 연구에서 여러 가지 변수들 중에 농도와 상대습도에 따라 MTBE의 분해율에 대하여 실험하였으며, 본 연구의 실험조건하에서 질소가 도핑된 TiO$_2$ 광촉매를 통해서 효과적으로 MTBE가 제거됨을 확인 할 수 있었다.

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