• Title/Summary/Keyword: adjacent channel

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Luminance Assessment of Outdoor Lighting for Advertisements at Night (옥외광고용 발광조명의 야간휘도분포 분석)

  • Shin, Hwa Young;Lee, Jong Soo;Kim, Jeong Tai
    • KIEAE Journal
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    • v.9 no.6
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    • pp.65-72
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    • 2009
  • Lighting for outdoor advertising is very common feature of building facades as they provide the information and commercial identification. As the interest of improving street beautification more widely, application of various lighting technologies has been develop for advertisement such as electric sign board and signage. Furthermore, the installation of higher sign luminance than needed has many negative consequences, including higher energy consumption and light pollution. There are now no standard for outdoor advertisements in terms of luminance, and installation of indiscreet outdoor advertisement without luminance consideration is becoming more commonplace. This study was to evaluate the luminous characteristics of outdoor advertising as a function of sign and building facade luminance, luminance ratio. Data were collected on 8 electric sign boards, 20 internally illuminated, externally illuminated, neon, and channel letter signs and 4 commercial areas. Photometric measurements were taken by CS-100(Minolta) and ProMetric-1400(Radiant Imaging) for various sign modes and sign design. Also luminance of building facades were analyzed according with CIE standard of maximum obtrusive light permitted for exterior lighting installations. The findings are as follows; (1) There were excessive luminance of electric sign boards that could affect adjacent building facade and night sky luminance. (2) Sings that are externally illuminated providing an inappropriate amount of light on to the outer surface of the sign caused higher building facade luminance and potential of unnecessary glare.

Convergence System to Guarantee Quality of Services (서비스 품질 보장을 위한 통합 전달 시스템)

  • Youn JiWook;Hong SeungWoo;Lee JongHyun;Yeom KyungWhan
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.42 no.12
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    • pp.25-30
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    • 2005
  • We propose and design a fully conversed Ethernet and TDM transport system to guarantee qualify of service for Ethernet packet. Developed convergence system can support not only L2 VPN service and premium multimedia service based on MPLS protocol but also TDM leased line service, simultaneously. Developed convergence system has the advantage of providing high reliability that realizes high-quality and real time communications due to assign QoS profile and guarantee bandwidth per channel consist of VCGs without affect adjacent channels. Evaluation for proposed system was successfully performed within the ling network.

Time- and Frequency-Domain Optimization of Sparse Multisine Coefficients for Nonlinear Amplifier Characterization

  • Park, Youngcheol;Yoon, Hoijin
    • Journal of electromagnetic engineering and science
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    • v.15 no.1
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    • pp.53-58
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    • 2015
  • For the testing of nonlinear power amplifiers, this paper suggests an approach to design optimized multisine signals that could be substituted for the original modulated signal. In the design of multisines, complex coefficients should be determined to mimic the target signal as much as possible, but very few methods have been adopted as general solutions to the coefficients. Furthermore, no solid method for the phase of coefficients has been proven to show the best resemblance to the original. Therefore, in order to determine the phase of multisine coefficients, a time-domain nonlinear optimization method is suggested. A frequency-domain-method based on the spectral response of the target signal is also suggested for the magnitude of the coefficients. For the verification, multisine signals are designed to emulate the LTE downlink signal of 10 MHz bandwidth and are used to test a nonlinear amplifier at 1.9 GHz. The suggested phase-optimized multisine had a lower normalized error by 0.163 dB when N = 100, and the measurement results showed that the suggested multisine achieved more accurate adjacent-channel leakage ratio (ACLR) estimation by as much as 12 dB compared to that of the conventional iterative method.

A Study on the Inter Cell Interference Analysis of Digital LMDS System (디지털 LMDS 시스템의 셀 내부 간섭 분석에 관한 연구)

  • 장태화;방효창;손성찬;김원후
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.9B
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    • pp.1608-1615
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    • 1999
  • In this study, we investigate the inter cell interference of LMDS(Local multipoint Distribution Service) system cell in LMDS system design process. There are several interference sources in LMDS system but we consider co-channel adjacent interference, cross-polarization interference, tx/rx interworking interference as three major factors. As the summation of each interference, C/N is keep 19 dB in 2km range but decreased gradually over 2km. Based on theoretical results, we process the experimental test and get results that C/I=20 dB have to be maintained to transmit the data successfully under rain fall attenuation condition. This experiential results are similar to the theoretical analysis results we examined.

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Design And Implementation Of ASK Modulator MMIC Operating At 5.8 GHz (5-8 GHz 대역 ASK 변조기 MMIC 설계 및 제작)

  • Jang, Mi-Sook;Ha, Young-Chul;Hur, Hyuk;Moon, Tae-Jung;Hwang, Sung-Beam;Song, Chung-Kun;Hong, Chang-Hee
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.11B
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    • pp.1595-1599
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    • 2001
  • In this paper, we have desired and implemented of ASK modulator MMIC operating at 5.8 GHz for OBE used in AGPS(Automatic Gate Passing System). The proposed ASK modulator MMIC was implemented to apply a single supply voltage of 3 V to the drain in order to decrease ACP(Adjacent Channel Power). As a result, it is exhibits a broad linear modulation range from 0.7 V to 3 V and an On/off characteristic over 40 dB. The layouts of ASK modulator MMICs was designed and fabricated by using ETRI 0.57m MESFET library The chip size was 1.0mm $\times$x1.0mm.

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Numerical Determination of Lateral Loss Coefficients for Subchannel Analysis in Nuclear Fuel Bundles (핵 연료집합체 부수로 해석을 위한 횡 방향 압력손실계수의 수치적 결정)

  • Kim, Sin;Park, Goon-Cherl
    • Nuclear Engineering and Technology
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    • v.27 no.4
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    • pp.491-502
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    • 1995
  • In accurate prediction of cross-flow based on detailed knowledge of the velocity field in subchannels of a nuclear fuel assembly is of importance in nuclear fuel performance analysis. In this study, the low-Reynolds number k-$\varepsilon$ turbulence model has been adopted in too adjacent subchannels with cross-flow. The secondary flow is accurately estimated by the anisotropic algebraic Reynolds stress model. This model was numerically calculated by the finite element method and has been verified successfully through comparison with existing experimental data. Finally, with the numerical analysis of the velocity Held in such subchannel domain, an analytical correlation of the lateral loss coefficient is obtained to predict the cross-flow rate in subchannel analysis codes. The correlation is expressed as a function of the ratio of the lateral How velocity to the donor subchannel axial velocity, recipient channel Reynolds number and pitch-to-diameter.

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Dynamics of Fish Larvae in the Han River Estuary and Kyunggi Bay, Korea

  • Park, Gyung-Soo;Han, Kyung-Nam
    • Journal of the korean society of oceanography
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    • v.32 no.4
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    • pp.202-207
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    • 1997
  • Species composition and abundance of fish larvae were studied from May 1988 through August 1989 in the Han River Estuary and adjacent Kyunggi Bay, Korea. Of 23 taxa identified, Coilia nasus, llisha elongata, and Cyprinidae spp. were dominated. Maximum density (3,5771/1,000m)$^3$ occurred in August 1988 and minimum (3/1,m$^3$) in February 1989. O1igo- ormesohaline species dominated during ebb tides while polyhaline species during flood tides. Correspondence analysis revealed that three distinctive species groups; oligohaline species, Coilia nasus, Ilisha elongata and Cyprinidae spp., which dominated at both channels of Kwanghwa Island (stations 1, 2), mesohaline species, Sardinella zunasi and Gobiidae spp., at the mouth of Yeomha Channel (station 3), and polyhaline species, Engraulis japonicus and Syngnathus schlegeli, in the middle of Kyunggi Bay (station 4). Coilia nasus was the most abundant species and reported first time in the study area. Given the species composition and density of fish larvae, the Han River Estuary is considered to be a major spawning and nursery ground for brackish water species such as Coilia nasus, Ilisha elongata and some Cyprinidae spp.

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Joint Spatial-Temporal Quality Improvement Scheme for H.264 Low Bit Rate Video Coding via Adaptive Frameskip

  • Cui, Ziguan;Gan, Zongliang;Zhu, Xiuchang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.6 no.1
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    • pp.426-445
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    • 2012
  • Conventional rate control (RC) schemes for H.264 video coding usually regulate output bit rate to match channel bandwidth by adjusting quantization parameter (QP) at fixed full frame rate, and the passive frame skipping to avoid buffer overflow usually occurs when scene changes or high motions exist in video sequences especially at low bit rate, which degrades spatial-temporal quality and causes jerky effect. In this paper, an active content adaptive frame skipping scheme is proposed instead of passive methods, which skips subjectively trivial frames by structural similarity (SSIM) measurement between the original frame and the interpolated frame via motion vector (MV) copy scheme. The saved bits from skipped frames are allocated to coded key ones to enhance their spatial quality, and the skipped frames are well recovered based on MV copy scheme from adjacent key ones at the decoder side to maintain constant frame rate. Experimental results show that the proposed active SSIM-based frameskip scheme acquires better and more consistent spatial-temporal quality both in objective (PSNR) and subjective (SSIM) sense with low complexity compared to classic fixed frame rate control method JVT-G012 and prior objective metric based frameskip method.

Fast Noise Reduction Approach in Multifocal Multiphoton Microscopy Based on Monte-Carlo Simulation

  • Kim, Dongmok;Shin, Younghoon;Kwon, Hyuk-Sang
    • Current Optics and Photonics
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    • v.5 no.4
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    • pp.421-430
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    • 2021
  • The multifocal multiphoton microscopy (MMM) enables high-speed imaging by the concurrent scanning and detection of multiple foci generated by lenslet array or diffractive optical element. The MMM system mainly suffers from crosstalk generated by scattered emission photons that form ghost images among adjacent channels. The ghost image which is a duplicate of the image acquired in sub-images significantly degrades overall image quality. To eliminate the ghost image, the photon reassignment method was established using maximum likelihood estimation. However, this post-processing method generally takes a longer time than image acquisition. In this regard, we propose a novel strategy for rapid noise reduction in the MMM system based upon Monte-Carlo (MC) simulation. Ballistic signal, scattering signal, and scattering noise of each channel are quantified in terms of photon distribution launched in tissue model based on MC simulation. From the analysis of photon distribution, we successfully eliminated the ghost images in the MMM sub-images. If the priori MC simulation under a certain optical condition is established at once, our simple, but robust post-processing technique will continuously provide the noise-reduced images, while significantly reducing the computational cost.

A Practical Measurement Method of the Occupied Bandwidth for 8-VSB DTV Signal Using Modified ACPR

  • Kim, Young Soo;Lee, Bong Gyou;Song, Kyeongmin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.7
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    • pp.3550-3565
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    • 2019
  • This paper proposes a new measurement method for the effective measurement of the 99% occupied bandwidth (OBW) at monitoring stations. Although the OBW measurement of radio signal is recommended by the International Telecommunication Union Radio (ITU-R) with several methods, there still does not exist a clear measurement recommendation or standard for terrestrial DTV signal on-air environment. Modified adjacent channel power ratio (MACPR), which can be applied to 8-VSB (Vestigial Side Band) DTV (Digital Television) signal, is herein defined to verify the results of measurements obtained using the proposed measurement method. MACPR is a proper measuring parameter for determining the measuring area of a monitoring station. From measurement results obtained in real field environment, it has been found that the OBW of 8-VSB DTV signal can be effectively measured in areas where the MACPR value is over 35 dB and when the measurements are repeated more than 600 times in the same reception site. It also has been verified that measured results are within an error range of +/-0.1% compared to results directly obtained at a transmission station. It is expected that the proposed method is able to be employed in order to determine the proper location of monitoring station and provide a reliable OBW measurement procedure for 8-VSB DTV signal on-air environment.