• Title/Summary/Keyword: spill-over

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Analysis on the spread variance by the spill-over spot on the spark sonance

  • Kim, Jeong-lae;Hwang, Kyu-sung
    • International Journal of Advanced Culture Technology
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    • v.7 no.1
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    • pp.237-242
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    • 2019
  • Spark variance technique is melded the jagged spill-over-sonance status of the glitter-differentiation knowledge level (GDKL) on the spark knowledge gestalt. The knowledge level condition by the spark knowledge gestalt system is comprised with the spill-over-sonance system. As to search a spot of the glitter situation, we are obtained of the spark value with black-red dot by the spill-over upper structure. The concept of knowledge level is comprised the reference of glitter-differentiation level for variance signal by the spark sonance gestalt. Further presenting a jagged variance of the GDKL of the maximum in terms of the spill-over-sonance gestalt, and spark spot sonance that was the a spark value of the far variance of the Spa-kg-FA-${\rho}_{MAXN}$ with $17.68{\pm}2.22units$, that was the a spark value of the convenient variance of the Spa-kg-CO-${\rho}_{MAXN}$ with $7.55{\pm}0.59units$, that was the a spark value of the flank variance of the Spa-kg-FL-${\rho}_{MAX}$ with $2.70{\pm}0.48units$, that was the a spark value of the vicinage variance of the Spa-kg-VI-${\rho}_{MAX}$ with $0.48{\pm}0.05units$. The spill-over sonance will be to appraisal at the jagged ability of the spill-over-sonance gestalt with black-red dot by the spark knowledge level on the GDKL that is presented the glitter-differentiation gestalt by the knowledge level system. Spill-over knowledge system will be possible to restrain of a gestalt by the special signal and to employ a spark data of spill-over sonance level.

The Design of X-band Cassegrain Antenna for Spill-over Suppression (Spill-over 억제를 위한 X-band 카세그레인 안테나 설계 연구)

  • Lee Woo-Sang;Jang Won;Lee Byoung-Moo;Yang Gi-Joo;Lee Sang-Heun;Yoon Young-Joong
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.17 no.9 s.112
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    • pp.829-835
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    • 2006
  • In this paper, new structure of the Cassegrain reflector antenna whose spill-over is efficiently reduced by modified reflectors is proposed for high power. It can be achieved by designing the geometry of subreflector in Cassegrain system using two hyperbolic curves in order to be suitable a lager beamwidth of feeding pattern without broadening main reflector. Finally, radiation efficiency and side lobe level of the proposed Cassegrain reflector antenna can be improved respectively 9 %, 10 dB than conventional one.

The Spill-over Effect of the Production and Investment of Telecommunication Service Industry (통신산업의 국민경제적 파급효과)

  • Kim, Sung-Whan;Kang, Im-Ho
    • Journal of Digital Convergence
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    • v.6 no.2
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    • pp.97-105
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    • 2008
  • This paper tries to measure the spill-over effect of the production and investment of telecommunication service industry (hereafter telecommunication industry), using the most recent data of 2003 input-output tables. The results are summarized as follows. First, the industries which have the biggest spill-over effect from the production of telecommunication industry is miscellaneous business service (including the sale commission of telecommunication service), other engineering services (including royalty), and business consumption. Second, the production of telecommunication industry induces more value-added, and less production, less import, and less employment than related industries such as radio and television equipment, communications and broadcasting equipment, and computer and peripheral equipment. Third, while the investment of telecommunication service amounts to 15% of its production, the effect of the investment on production, value-added, consumption, and employment reaches 70% of that of its production. The policy implication of this paper is that the telecommunication industry contributes to overall economy mainly through its investment.

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Development of Oil Spills Model and Contingency Planning ill East Sea (유류확산모델 개발 및 동해의 유류오염 사고대책)

  • RYU CHEONG-RO;KIM HONG-JIN
    • Journal of Ocean Engineering and Technology
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    • v.19 no.4 s.65
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    • pp.35-41
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    • 2005
  • There has been increasing offshore oil exploration, drilling, and production activities, as well as a huge amount of petroleum being transported by tankers and pipelines through the ocean and costal environment. Assessment must be made of the potential risk of damage resulting from the exploration, development and transportation activities. This is achieved through predictive impact evaluations of the fate of hypothetical or real oil spills. VVhen an oil spill occurs, planning and execution of cleanup measures also require the capability to forecast the short-term and long-term behavior of the spilled oil. A great amount of effort has been spent by government agencies, oil industries, and researchers over the past decade to develop more realistic models for oil spills. Numerous oil spill models have been developed and applied, most of which attempt to predict the oil spill fate and behavior. For an actual contingency planning, the oil fate and behavior model should be combined with an oil spill incident model, an environmental impact and risk model and a contingency planning model. The purpose of this review study is to give an overview of existing oil spill models that deal with the physical, chemical, biological, and socia-economical aspects of the incident, fate, and environmental impact of oil spills. After reviewing the existing models, future research needs are suggested. In the study, available oil spill models are separated into oil spill incident, oil spill fate and behavior, environmental impact and risk, and contingency planning models. The processes of the oil spill fate and behavior are reviewed in detail and the characteristics of existing oil spill fate and behavior models are examined and classified so that an ideal model may be identified. Finally, future research needs are discussed.

Performance of ADSL with crosstalks from ISDN and HDSL (ISDN과 HDSL 혼선잡음을 고려한 ADSL 성능분석)

  • 김재욱;정우곤
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.6B
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    • pp.867-873
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    • 2001
  • 최근 들어 초고속통신에 많이 이용되는 ADSL의 경우 케이블(bundle)안에 ISDN이나 HDSL이 제공되는 경우, 대역이 부분적으로 중첩되거나 불완전한 대역 필터링 때문에 그에 따른 spill-over 혼선 잡음의 영향을 받게 된다. 본 논문에서는 유선 선로에서 ISDN과 HDSL에 의한 ADSL의 성능 저하를 분석하였다. 그 결과, 이들에 의한 spill-over 혼선잡음은 ADSL의 성능에 많은 저하를 가져오며, 특히 HDSL의 경우 심각한 혼선잡음을 일으킴을 확인하였다.

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USING SATELLITE SYNTHETIC APERTURE RADAR IMAGERY TO MAP OIL SPILLS IN THE EAST CHINA SEA

  • Shi, Lijian;Ivanov, Andrei Yu.;He, Mingxia;Zhao, Chaofang
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.981-984
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    • 2006
  • Oil pollution of the ocean is a major environmental problem, especially in its coastal zones. Synthetic aperture radar (SAR) flown on satellites, such as ERS-2 and Envisat, has been proved to be a useful tool in oil spill monitoring due to its wide coverage, day and night, and all-weather capability. The total 120 SAR images containing oil spill over the East China Sea were collected and analyzed, ranging in date from July 23, 2002 to November 11, 2005. After preprocessed, SAR images were segmented by adaptive threshold method. The oil spill images were incorporated into GIS after distinguished from look-like phenomena, finally we presented the oil spills distribution map for the East China Sea. The wide-swath and quick-looks SAR imagery for mapping of oil spill distribution over large marine areas were proved to be useful when full resolution data are not available. After the temporal and spatial distribution of the oil spills were analyzed, we found that most of oil spills were distributed along the main ship routes, which means the illegal discharge by ships, and the occurrence of oil spill detected on SAR images acquired during morning and summer is much higher than during evening and winter.

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An Analysis of the Figure of Merit depending on the cut-off size of a Small Reflector for Satellite Broadcast Receiving Antenna (위성방송 수신용 소형 반사면 안테나의 절단 크기에 따른 성능지수의 분석)

  • Lim, Gye-jae
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.6 no.3
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    • pp.152-155
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    • 2013
  • In this paper, the reduction of the figure of merit depending on the increased spill-over when the parabolic reflector is cut off partially for low-profile configuration in the satellite broadcast receiving antenna is analyzed. Also for the accurate analysis and simulation, it is considered that the noise temperature is increased due to the effect of ground thermal noise toword the sidelobes and back lobes when the antenna is tracked from $0^{\circ}$ to $60^{\circ}$ in elevation angle, and that the total noise temperature is increased because to the noise figure of LNA. As the results, noise temperature is increased up to about 15K and G/T ratio is decreased to about 2.5dB, when the reflector is cut 35% off partially.

Actual Conditions of Spill Over by the Japan TV Broadcasting Signals (일본 TV 방송신호의 전파월경 실태)

  • Hue, Young-Tae;Kim, Hyun;Woo, Jong-Woo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.11A
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    • pp.1213-1218
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    • 2007
  • In this study, we have been constructed measuring system for spill over by the Japan TV broadcasting signals and analyzed those signals using APD curve. In Busan, we have been measured channel of Japan TV broadcasting signals during 9 months. The quality of image is that maximum grade is 2.5 level, and the quality of sound is that maximum grade is 3 level. In the result of analysis for measured Japan TV broadcasting signals, we have been observed Japan TV broadcasting signals those we have been chosen the ch 36 and ch 38, plotted the APD curve of each channel for a season, in Specially.

Failure Characteristics of Oil Boom Considering the Nonlinear Interaction of Oil Boom with Waves (Oil boom과 파랑의 비선형상호작용을 고려한 Oil Boom의 누유특성)

  • Cho, Yong-Jun;Yoon, Dae-Kyung
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.23 no.3
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    • pp.193-204
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    • 2011
  • To develop more robust oil boom which is vulnerable to various failure mode under severe weather condition, highly accurate wave model is developed using Spatially filtered Navier-Stokes Eq., LDS (Lagrangian Dynamic Smagorinsky model) for residual stresses, SPH (Smoothed Particle Hydrodynamics). To clarify the hydraulic characteristics of floating type oil boom, we numerically simulate the behavior of oil spill around oil boom under very energetic progressive waves. At the first stage, we firmly anchored the oil boom, and then, allowed the excursion of the oil boom. It turns out that oil boom with skirt of enough length (longer than 30% of depth) effectively confines the oil spill even against very energetic waves. We can also observe obliquely descending vertical eddies between y = 1~2 m as horizontal vortices shedding at the interface of oil spill and water are diffused toward the bottom, which is believed to be the birth, growing and break-down of Kelvin-Helmholz wave.

Oil Spill Simulation by Coupling Three-dimensional Hydrodynamic Model and Oil Spill Model (3차원 동수역학모형-유류확산모형 연계를 통한 유출유 거동 모의)

  • Jung, Tae-Hwa;Son, Sangyoung
    • Journal of Ocean Engineering and Technology
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    • v.32 no.6
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    • pp.474-484
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    • 2018
  • In this study, a new numerical modeling system was proposed to predict oil spills, which increasingly occur at sea as a result of abnormal weather conditions such as global warming. The hydrodynamic conditions such as the flow velocity needed to calculate oil dispersion were estimated using a three dimensional hydrodynamic model based on the Navier-Stokes equation, which considered all of the physical variations in the vertical direction. This improved the accuracy compared to those estimated by the conventional shallow water equation. The advection-diffusion model for the spilled oil was combined with the hydrodynamic model to predict the movement and fate of the oil. The effects of absorption, weathering, and wind were also considered in the calculation process. The combined model developed in this study was then applied to various test cases to identify the characteristics of oil dispersion over time. It is expected that the developed model will help to establish initial response and disaster prevention plans in the event of a nearshore oil spill.