• Title, Summary, Keyword: EMC

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Discharge Characteristics of Indicator Microorganisms from Agricultural-Forestry Watersheds (농지-임야에서 발생하는 지표미생물 유출 특성)

  • Kim, Geonha
    • Journal of The Korean Society of Civil Engineers
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    • v.28 no.1B
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    • pp.153-160
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    • 2008
  • To estimate microbial contaminant loading discharged from diffuse sources, rainfall runoff of six rainfall events were monitored at three study watersheds of forestry and agricultural land use. Monitored indicator microorganism constituents were total coliform (TC), fecal coliform (FC), Escherichia coli (EC), and fecal streptococcus (FS). Soil loss during elevated flow rate caused higher suspended solid concentrations. Indicator microorganism concentrations were closely related with flow rate. TC event mean concentration (EMC) from unpolluted forestry was $5.3{\times}10^3CFU/100ml$, FC EMC was $1.4{\times}10^3CFU/100ml$, EC EMC was $1.1{\times}10^3CFU/100ml$, and FS EMC was $2.9{\times}10^2CFU/100ml$. From a watershed with agricultural-forestry land use, TC EMC was $1.7{\times}10^5CFU/100ml$, FC EMC was $8.5{\times}10^4CFU/100ml$, EC EMC was $8.9{\times}10^4CFU/100ml$, and FS EMC was $3.4{\times}10^4CFU/100ml$. Mixed land use of agricultural-forestry with bigger area, TC EMC was $1.9{\times}10^5CFU/100ml$, FC EMC was $9.6{\times}10^4CFU/100ml$, EC EMC was $7.0{\times}10^4CFU/100ml$, and FS EMC was $5.1{\times}10^4CFU/100ml$.

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EMC Design of Communication System on the Basis of EMC Design Rule (EMC Design Rule을 이용한 통신 System의 EMC Design)

  • 박학병;박종성;이승한;강석환
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.12 no.1
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    • pp.77-83
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    • 2001
  • We analyzed the mechanism of EM emission in telecommunication system and extracted the dominant parameter in EMC design. The I/O cable, ventilation hole and shield design of chassis are important EMC design Issues in telecommunication systems. Because telecommunication systems have much more I/O cables than other electronic products, EMC design of I/O cable is very important in telecommunication systems. Therefore by the method of experimentation and simulation, EM coupling mechanism of I/O cable was analyzed and the design rule for low emission was extracted. On the base of these EMC design rules, EMC design of telecommunication system was executed without complex redesign or debug. The result obtained by these methods was shown in this paper.

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The Review on the Enzyme System and Biochemical Properties of Enzyme Modified Cheese(EMC) (Enzyme Modified Cheese(EMC)의 효소체계 및 생화학적 특성에 대한 고찰)

  • Jeon, Woo-Min
    • Journal of Dairy Science and Biotechnology
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    • v.26 no.2
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    • pp.39-43
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    • 2008
  • EMC have a similar enzymatic reaction to cheese, but the EMC produce the stronger flavors than cheese by much more enzymatic reaction. It is important to find appropriate enzyme in order to develop these kind of superior EMC. Calf PGE is more suitable than that of kid and lamb to develop the mild cheese flavors. Especially, it was known that animal esterase and peptidase were more benefit than microbial enzyme for Cheddar cheese flavors. On the Cheddar and Swiss cheese, EMC flavors were much more 3 times than the cheese flavors. In the ratio of each component, butyric acid, myristic acid, palmitic acid and oleic acid were high in free fatty acid, and glutamic acid, valine, leucine and lysine were high in free amino acid of the Cheddar EMC.

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Power System and Electromagnetic Compatibility(EMC) (전력계통과 전자기적합성(EMC))

  • Kim, Oun-Seok;Kim, Jae-Chul;Choi, Joon-Ho;Moon, Jong-Fil
    • Proceedings of the KIEE Conference
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    • pp.524-526
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    • 2002
  • 본 논문에서는 전력계통 관련 기기에서 문제가 되고 있는 전자기적합성(Electromagnetic Compatibility, 이하 EMC)을 다루고자 한다. 전력계통은 서지와 같은 많은 전자기 장해를 발생한다. 그래서 최근 제정 및 개정되고 있는 전자기기 회로가 포함되어 있는 IEC 규격에서는 대부분 EMC 시험을 포함하고 있다. 본 논문에서는 전력계통과 EMC 연관성을 검토하고자 한다. 또한 주요 중전기기의 EMC 규격 동향을 소개하고자 한다. 마지막으로 국내 전력계통 기기에서 발생한 실제 EMC 문제를 소개하고자 한다.

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EMC Design of Communication System on the basis of EMC Design Rule (EMC Design Rule을 이용한 통신 System의 EMC Design)

  • 박학병;박종성;이승한;강석한;박현길
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • pp.272-276
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    • 2000
  • 본 논문에서는 I/O Cable을 가지는 일반 통신시스템의 전자파 방사 Mechanism을 분석하고, Design에 있어 중요한 Parameter를 도출하였다. 중요한 Design Parameter로 도출된 I/0 Cable의 Coupling mechanism을 실험 및 상용 Software를 이용한 Simulation방법에 의해 분석하고, 이에 대한 EMC Design Rule을 제시하였다. 도출된 EMC Design Rule을 준수하여 Design을 실현하고, 그 효과를 분석하였다. EMC Design Rule에 기반을 둔 개발을 통해 제품의 Redesign및 복잡한 Debug 과정이 없이 효과적으로 전자파 양립성 규격을 만족하였다.

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KoDSat System Level EMC(Electro Magnetic Compatibility) Test and an Analysis of the Test Results (검증위성 시스템레벨 전자기파(EMC) 시험 및 결과에 대한 분석)

  • Seo, Min-Seok;Park, Seok-Jun;Sim, Eun-Seop;Kim, Se-Yeon;Chae, Jang-Su
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.34 no.4
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    • pp.102-109
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    • 2006
  • In this paper, the system level EMC radiated emission test results of KoDSat(Korea Demonstration Satellite), its affects upon the Launch vehicle and H/W improving methods regarding its over exceed value of EMC specification are discussed. Regarding its over exceed value, we estimated that DAU of KoDSat generated the exceeded EMC noise source, and these test results were analyzed using the EMC2000 tool to find out how did it affect the FTS(Flight Termination Subsystem) of KSLV-1(Korea Small Launch Vehicle). To diminish the EMC noise source of UHF(430.1Mhz) band level, we redesigned the DAU power board to be applied the various schemes for EMI noise reduction such as grounding, shielding and EMI filtering, and also verified these reworks to analyze its diminishing affects in UHF band level by means of performing the DAU box level EMC test and performing the second KoDSat's system level EMC test.

Equilibrium Moisture Content of Korean Ginseng (인삼(人蔘)의 평형함수율(平衡含水率)에 관(關)한 연구(硏究))

  • Choi, B.M.;Lee, J.H.;Park, S.J.;Kim, C.S.;Rhee, J.Y.
    • Journal of Biosystems Engineering
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    • v.17 no.3
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    • pp.247-259
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    • 1992
  • This study intended to measure the desorption and adsorption EMC of four years old Peeled ginseng, Unpeeled ginseng and Taegeuk ginseng under various conditions$20^{\circ}C$, $30^{\circ}C$, $40^{\circ}C$, $50^{\circ}C$) and five levels of relative humidity from 31% to 88%) by the static method. Four widely used EMC models were selected and evaluated. Also the empirical model was evaluated. The results are summarized as follows ; 1) EMC difference between ginseng size was not found but found between ginseng species. EMC difference between Peeled ginseng and Unpeeled ginseng was not found. EMC of Peeled ginseng and Unpeeled ginseng was higher than that of Taegeuk ginseng. 2) The hysteresis, which is difference between desorption and adsorption EMC, was found. Desorption EMC was higher than adsorption EMC. The hysteresis at the same temperature decreased as relative humidity increase. The difference of hysteresis between Peeled ginseng and Unpeeled ginseng was not large and the hysteresis of Taegeuk ginseng was smaller than those of other species. 3) Among the selected models, Henderson model was the best to predict the adsorption EMC of White ginseng(Peeled and Unpeeled ginseng), and Oswin model was the best to predict the desorption EMC of White ginseng and the desorption and adsorption EMC of Taegeuk ginseng. The models are as follows ; (a) White ginseng(Peeled and Unpeeled ginseng) ${\circ}$ Desorption EMC(Oswin model) : $$M=(0.1272-0.0007420T){\cdot}[RH/(1-RH)]^{(0.4164+0.001368T)}$$ ${\circ}$ Adsorption(Henderson model) : $$1-RH={\exp}[-0.0003480T_k\;{M_o}^{0.9231}]$$ (b) Taegeuk ginseng ${\circ}$ Desorption EMC(Oswin model) : $$M=(0.1051-0.0008439T)[RH/(1-RH)]^{(0.4553+0.003425T)}$$ ${\circ}$ Adsorption EMC(Oswin model) : $$M=(0.08247-0.0007559T){\cdot}[RH/(1-RH)]^{(0.5760+0.005540T)}$$ 4) The developed empirical models could predict the desorption and adsorption EMC for White and Taegeuk ginseng more precisely than selected models. The empirical models are as follows ; (a) White ginseng(Peeled and Unpeeled ginseng) ${\circ}$ Desorption EMC : $$M=0.124-0.000647T-0.216RH+0.373RH^2$$ ${\circ}$ Adsorption EMC : $$M=0.0879-0.000663T-0.197RH+0.399RH^2$$. (b) Taegeuk ginseng ${\circ}$ Desorption EMC : $$M=0.159-0.000728T-0.429RH+0.565RH^2$$ ${\circ}$ Adsorption EMC : $$M=0.123-0.000662T-0.384RH+0.555RH^2$$.

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EMC Performance Improvement of Distribution Automation Circuit-Breaker by Modified Installing Method of Control Cable (제어케이블의 설치기법 개선에 의한 배전자동화용 개폐기의 EMC 성능 향상)

  • 김언석;김재철
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.17 no.5
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    • pp.60-67
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    • 2003
  • The goal of this paper is to improve EMC performance of circuit breaker. Circuit breaker and control cubicle are interconnected by multi control cable. Also many control cables are laid on each apparatus. These control cables are directly connected by electronic components. So control cables are very important to improve EMC performance of circuit breaker. This paper suggests installing a ground conductor in parallel(PGC) to control cables. Also this paper suggests using shielding cables as secondary cables of voltage transformer in circuit breakers, and grounding both ends of shielding. After applying suggested methods, we verified EMC performance of circuit breaker is improved.

Fracture Toughness of IC Molding Compound Materials(II) (IC 몰딩 콤파운드 재료의 파괴 인성치(II))

  • 김경섭;신영의
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.11 no.5
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    • pp.353-357
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    • 1998
  • Cracking problem of Epoxy Molding Compound(EMC) is critical for the reliability of the plastic package during temperature cycling and IR-reflow condition. Fracture toughness of EMC, which is defined as the resistance of EMC to the crack propagation, is a useful factor in ht estimation of EMC against package crack. Thus, development of EMC having high fracture toughness at a given loading condition would be important for confirming the integrity of package. In this study, toughness of several EMC was measured by varying the test conditions such as temperature, loading speeds, and weight percent of filler in order to quantify the variation of toughness of EMC under various applicable conditions. It was found from the experiments that toughness of all EMC has following trends, i.e., it rapidly decreases over the glass transition temperature, remains almost same or little decreases below $0^{\circ}C$. It decreases with the growth of cross head speed in EMC and the weight percent of filler as the degree of brittleness of EMC increases with the amount of filler content.

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On the Problems of EMC Test Site and EMC Antennas (EMC 측정 시험장과 EMC 안테나에 관한 문제점)

  • Kim, Ki-Chai
    • Journal of The Institute of Information and Telecommunication Facilities Engineering
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    • v.2 no.1
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    • pp.78-87
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    • 2003
  • One of the most difficult and important problems associated with radiated electromagnetic emissions from digital devices are the determination of antenna factor and site acceptability of an open area test site. This paper presents the problems of the open area test site and EMC antennas far measuring electromagnetic interferences radiated from the equipements. It seems desirable that the antenna factor of EMC antennas be revised to the antenna factor with zero reflection presented in this paper for accurate measurements.

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