• 제목/요약/키워드: media excess

검색결과 85건 처리시간 0.035초

다공성물질을 이용한 초단열 연소장치에서의 연소특성의 실험적 연구 (An Experimental Study on the Combustion Characteristics with Superadiabatic Combustor in Porous Media)

  • 채재우;;심민섭;정성찬
    • 설비공학논문집
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    • 제6권4호
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    • pp.399-405
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    • 1994
  • Beacuse of the energy resources exhaustion, the aggravating environmental air pollution and the smoke phenomena etc., the importance of clean gas fuel compared with liquid fuel is highly considered in recent years. The combustion system which consists of porous media is actively studied as a new method for solving above problems. Therefore, excess enthalpy combustion using porous media was interested by many researchers and investigated through numerical and experimental analysis. In this study, the simplified combustor has the unique combustion characteristics of mixture gas preheated effect using radiative and convective heat energy by changing the flow passage of unburned gas with solenoid valves and has the intensive excess enthalpy phenomena As the result of according to reduce equivalence ratio, flame temperature was remarkably higher than adiabatic flame temperature. This show the ability of super-lean combustion.

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미디어 환경개념의 정책적 함의: 공익성 관련 논의를 중심으로 (A Concept of Media-Environment and Its Policy Implications: Focusing on the Policy Discussions Concerning the Public Interest Idea)

  • 김평호
    • 한국언론정보학보
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    • 제43권
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    • pp.152-172
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    • 2008
  • 기본적으로 미디어 공익성이라는 개념은 사회적 차원에서 미디어에 대한 비판적 대응과 관리, 통제를 위해 확립된 이념체계, 즉 사회적 이익의 실현을 위해 미디어에 개입하는 철학적 근거로 기능해오고 있다. 그러나 문제는 공익성 철학을 미디어 융합시대에 걸맞은 현실의 정책으로 해석 적용하기 위한 수많은 논의와 연구에도 불구하고 실제 제시되는 구체적 정책내용이나 방안은 융합환경 이전이나 이후에도 사실상 유사하다는 점이다. 이 같은 한계는 여러 이유가 있겠지만 공익성의 제도화 관련 논의가 대체로 미디어에 대한 도구적 관점에 기초해있기 때문이라고 할 수 있다. 그러나 미디어는 도구, 또는 도구의 집합 이상의 의미를 갖고 있으며 이는 '미디어 과잉'이라는 사회적 상황을 조성하고 있는 융합시대에 들어 더욱 분명해지고 있다. 이러한 문제의식에서 출발하는 이 연구는 공익성과 관련한 기존의 정책과 정책논의가 가지고 있는 미디어에 대한 시각과 인식의 한계를 '미디어-환경'개념에 입각해 반성적으로 짚어보고자 한다. 미디어-환경개념은 말 그대로 미디어를 환경, 특히 '문화적 생태환경 체제'로 인식하는 것을 의미한다. 미디어에 대한 환경론적 접근은 융합시대에 요구되는 미디어 공익성 관련 정책의 철학적 기초와 내용을 보다 풍성하게 하는 한편 공익성의 실천적 기준과 주체의 범위를 더욱 확대해준다는 점에서 그 의의를 찾을 수 있다.

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FAME Analysis to Monitor Impact of Organic Matter on Soil Bacterial Populations

  • Kim, Jong-Shik;Joo, Jin-Bee;Weon, Hang-Yeon;Kang, Chang-Seong;Lee, Si-Kyung;Yahng, Chahng-Sool
    • Journal of Microbiology and Biotechnology
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    • 제12권3호
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    • pp.382-388
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    • 2002
  • In order to assess the effects of organic fertilizer on soil microbial community structure and diversity in the greenhouse fields, fatty acid methyl ester (FAME) was analyzed by the MIDI (Microbial ID, Inc., Newark, DE, U.S.A.) system and enumerations were performed. In relation to bacterial division of each sample, low GC Gram-positive bacteria were predominant among bacteria cultured on aerobic bacteria media. On the other hand, alpha subdivision was predominant on proteobacteria of control and OM (organic matter) 1 treated plot, and Flavobacterium spp. existed in OM2 plot on crystal violet media of all samples. Shannon-weaver Index (H) of OM1 plot varied most by 1.9 and 5.0 among bacteria cultured on aerobic bacteria media and crystal violet media, respectively. Our results revealed that addition of the organic wastes to soil led to a highly diverse microbial community, but the excessive amounts of organic and mineral fertilizer applied in the greenhouse fields produced excess nutrients in soil and led to simplification on bacterial populations.

항생제를 이용한 Bifidobacteria의 선택배지 (Selective Media Containing Antibiotics for Counting Bifidobacteria)

  • 이정준;신명수;나석환;배형석;백영진
    • 한국미생물·생명공학회지
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    • 제22권3호
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    • pp.309-315
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    • 1994
  • Selective agar media were constructed for the counting of bifidobacteria in dairy produ- cts containing bifidobacteria, lactobacilli and streptococci. This media containing antibiotics inhibited the growth of lactobacilli and streptococci at less than 10$^{5}$ cfu/ml, but had no influence on the recovery of bifidobacteria. In order to inhibit the growth of 10$^{5}$ cfu/ml of lactobacilli and streptoco- cci, the addition of 1.0~2.0 $\mu$g/ml of tetracycline in BL agar medium was needed. When 25 $\mu$g/ml of neomycin and paromomycin were mixed with 1.0 $\mu$g/ml of tetracycline in BL agar medium, it was able to inhibit the growth of 10$^{6}$ cfu/ml of lactobacilli and streptococci but had a little negative effect on the recovery of colonies of bifidobacteria. The results revealed that the BL agar medium containing 1.0 $\mu$g/ml of tetracycline was suitable to count the cell number of bifidobacteria selecti- vely in the presence of a 1 to 10$^{5}$-fold excess of L. casei, L. acidophilus and S. salivarius subsp.thermophilus.

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Effect of Media Components and Phytohormones on in vitro Frond Proliferation of Lemna gibba G3 and 24 Additional Lemna gibba Strains

  • Moon, H.K.
    • Plant Resources
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    • 제1권2호
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    • pp.98-104
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    • 1998
  • The effects of basal media, sucrose and phytohormone concentrations, and gelling agent combinations on in vitro frond proliferation of Lemna gibba G3 and 24 additional Lemna gibba strains were examined. Frond proliferation was equivalent on Schenk and Hidebrand. Murashige and Skoog. Nitsch and Nitsch, and Gamborg's B5 media and poor on murashige and Skoog medium in the absence of benzyladenine. With the addition of benzyladenine, Schenk and Hildebrand and Gamborg's B5 Were superior and equivalent. The addition of benzuyladenine increased equally frond proliferation at either 1 or $10{\mu}M$, however at $10{\mu}M$ fronds were severely curled or fused. Benzyladenine and thidiazuron suppressed root growth but kinetin was found to greatly enhance root growth. Gibberellic acid inhibited frond proliferation. Frond proliferation was significantly different on the four sucrose concentrations of 0, 1, 3, and 5% Among them, 3% sucrose was found to be superior. The reduced frond size observed in cultures grown on 8% sucrose could be explained by showing medium osmotic potential in excess of frond water potential. Gell agents also varied significantly in their ability to promote frond proliferation with 0.25% Gelrite or a mixture of 0.15% Gelrite and 0.4% agar. Proliferation of 25 Lemna gibba strains on medium neat optimal for Lemna gibba G3 showed a six-fold variation across strains with Lemna gobba G3 placing in the top 5 fastest proliferating strains.

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Highly Stable Photoluminescent and Magnetic Multilayers Using Nucleophilic Substitution Reaction in Organic Media

  • 조진한
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2010년도 제39회 하계학술대회 초록집
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    • pp.262-262
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    • 2010
  • We introduce a novel and efficient strategy for producing free-standing functional films via photo-crosslinking and electrostatic layer-by-layer (LbL) assembly, which can allow the buildup of hydrophilic multilayers onto hydrophobic surfaces. Hydrophobic multilayers were deposited on ionic substrates by a photo-crosslinking LbL process using photo-crosslinkable polymers. The photo-crosslinked surface was converted to an anionic surface by excess UV light irradiation. This treatment allowed also the stable adhesion between metal electrode or cationic polyelectrolyte and hydrophobic multilayers. After dissolving the ionic substrates in water, the formed free-standing films exhibited unique functionalities of inserted components within hydrophobic and/or hydrophilic multilayers.

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순환 여과식 양식 시설에 이용될 수종의 여과 재료의 효능에 관한 연구 (The Ammonia Removal Capacity of a Few Kinds of Filter Media in a Water Reuse quaculture System)

  • 김인배;김평기;지영옥
    • 한국수산과학회지
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    • 제20권6호
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    • pp.561-567
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    • 1987
  • 순환 여과식 양식에 있어서 사육수에 축적되는 암모니아를 여과 재료별로 그 제거 능력을 알아보고, 실제 산업에의 적용에 관한 문제를 검토하였다.. 여과 재료는 첨모직(pile cloth), 스카이 라이트 골판(corrugated skylight roofing plate), 요철 플라스틱판(embossed plastic plate), 및 자갈의 4종류를 사용, $90cm\times60cm\times60cm$(깊이)의 수조에 각각 2개씩 같은 재료를 넣어서 모두 8개를 설치하였다. 주입수는 부산수산대학 순환여과식 양식 시설의 어류사육 탱크에서 나오는 물을 사용하여 그 속에 함유된 암모니아 제거능력을 측정하였다. 정상적 기능을 발휘하는 두 기간의 여과 재료별 1일 $1m^3$의 여과제 설치 용적당 평균 암모니아 제거 능력은 다음과 같았다. 1) 첨모직 8.381g 2) 2) 스카이 라이트 골판 7.834g 3) 요철 플라스틱판 7.797g 4) 자갈 7.051 g 이와 같이 주기능 발휘 기간동안에는 재료별 차이가 별로 없었지만 그 기간의 길이 차이, 청소의 난이도, 설치 비용 등을 고려해야 한다. 특히 대형 여과조의 경우, 자갈 여과조를 청소하는 일은 대단히 어렵고, 첨모직 여과조는 그 설치 작업이 까다롭고, 배수시 그 구조를 유지하는 데 어려운 문제가 따른다. 이러한 관점에서 볼 때 스카이 라이트 곡판과 요철 플라스틱판이 가장 적당하다고 생각된다. 그러나, 실제 설치시는 재료의 입수 가능성, 가격은 물론, 사용중 또는 계획중의 여과 탱크에의 적합 여부도 고려되어야 한다.

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연소 특성에 따른 강판 표면 산화거동에 관한 연구 (A Study on Behavior of Steel Surface Oxidation with Characteristics of the Combustion)

  • 김슬기;강기중;이기만
    • 한국수소및신에너지학회논문집
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    • 제28권4호
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    • pp.392-400
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    • 2017
  • An experimental study was conducted to investigate behavior of steel surface oxidation with characteristics of the combustion. The excess entalphy combustion in porous media system was applied to implement the direct radiation heating system. The surface oxidation thickness (SOT) of fuel-lean was thicker than the SOT of fuel-rich. Also, the SOT was increased by increasing residence time. Detailed explanations were given by SEM and EDS analysis.

생물막을 이용한 상수 원수에서의 암모니아 제거 특성 (Ammonia Removal Characteristics of Biolfilm Reactor)

  • 신항식;임경호;이상민
    • 상하수도학회지
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    • 제10권1호
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    • pp.78-84
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    • 1996
  • The presence of ammonia, usually in the form of ammonium ion ($NH_4{^+}$), can enhance bacterial growth m the distribution system and make the production of drinking water more costly if ammonium must be removed to ensure good disinfection. Removal of ammonia by biological oxidation could be economical which prevents excess chlorine dosage In this research, effects of hydraulic retention time (HRT) and media type on the ammonia removal efficiencies of submerged biofilm reactor were investigated. The biofilm reactors combined the characteristics of high biological solids capture efficiency and good hydraulic control. The results indicate that biofilms can remove over 77 percent of the ammonia with HRT of longer than 2 hr even at low temperature ranging from 14.6 to $16.6^{\circ}C$. The HRT has a significant effect on nitrification. The overall nitrification and efficiency of ammonia removal increase with increasing HRT. It has also been observed that when the fibrous media was used, the ammonia removal, nitrification rate and endurance to shock improved.

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단일 생물막 반응기에서 역세척과 다공성 생물막 담체가 질소제거에 미치는 영향

  • 이수철;유익근;김동진
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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    • pp.451-454
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    • 2000
  • This study was carried out to investigate the effects of hydraulic backwash load and porous ceramic media on the biological nitrogen removal efficiencies of a biological aerated filter. An upflow anoxic-oxic biological aerated filter(AO-BAF) with porous ceramic media can remove nitrogen by nitrification and denitrification in single unit. After the AO-BAF backwash, nitrogen removal efficiency was lowest and gradually increased to the steady state. Nitrification efficiency, however, showed the opposite result. It is likely that the biofilms are exposed to aerobic condition as the excess biofilms were sloughed off by backwashing

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