• 제목/요약/키워드: lager

검색결과 243건 처리시간 0.028초

맥주의 발효과정에서 효모와 발효온도가 황화수소의 발생에 미치는 영향 (Effects of Yeast Strains and Fermentation Temperatures in Production of Hydrogen Sulfide During Beer Fermentation)

  • 김영란;문승태;박승국
    • 한국식품과학회지
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    • 제40권2호
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    • pp.238-242
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    • 2008
  • Ale과 lager 효모를 이용하여 맥주발효 실험한 결과, lager 효모는 발효가 활발하게 일어나는 발효 초기에 많은 양의 황화수소를 발생하였으며 ale 효모보다 더욱 많은 양의 황화수소가 발생되었다. 효모의 증식이 활발한 발효 초기에 많은 양의 황화수소가 만들어지는 것을 보아 효모의 증식과 황화수소의 생성 사이에는 상관관계가 있음을 확인하였다. 온도 차이에 따른 실험 결과에서, lager 효모의 경우에는 발효 온도가 높은 것이 발효율이 더 높아 발효 시간을 줄일 수 있는 장점은 있으나, 많은 양의 황화수소가 발생되는 것을 알 수 있었다. 또한 APL은 $15^{\circ}C$에서 발효시켰을 때, 발효 끝 부분에서 많은 양의 황화수소가 발생되었는데, 이것은 맥주에 좋지 않은 냄새의 원인이 되므로 장시간의 숙성기간을 필요로 한다는 것을 의미한다. EA의 경우에는 낮은 온도에서 오히려 더 많은 양의 황화수소가 생성이 되었으나, HA의 경우에는 lager 효모에서와 같이 높은 온도에서 더 많은 양의 황화수소가 생성되었는데, 이는 각 효모마다 $H_2S$를 생성하기에 적합한 온도가 있음을 의미한다.

녹차 추출물을 첨가한 polyphenol 강화 맥주의 발효 특성에 대한 연구 (The Effect of Green Tea Extracts on the Fermentation Properties of Polyphenol-Enriched Beers)

  • 염행철
    • 대한가정학회지
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    • 제46권3호
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    • pp.49-55
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    • 2008
  • The purpose of this study was to investigate the effects of green tea extracts (GTE) on the fermentation properties of polyphenol-enriched beers. As such, the formation patterns of tannoid in beer with GTE were investigated at 3 different infusion times, while the ale and the lager beers fortified with GTE were analyze to ascertain effects on gravity, pH, yeast viability, total polyphenol, and tannoid during fermentation period. The results were as follows: 1) The formation of tannoid in beer with GTE in the tannometer; In reaction of GTE with polyvinylpyrrolidon (PVP), control lager beer peaked in the formation of tannoid at $70\;{\sim}\;80\;mg$ of PVP, the 1st extract exceeded the detection limit, the 2nd extract at $170\;{\sim}\;180\;mg$, while the third extract at $150\;{\sim}\;160\;mg$ of PVP. The GTE were slow in reacting with PVP, and their formation patterns were different from those of polyphenols from barley and hop. 2) Ale fermentation; The final alcohol content was 9.25% (ABV). The addition of GTE increased the yeast viability after 2 days and finally reached 52.3% from 30.9%. Total polyphenol in GTE beer increased by 1.5 times (p < .05). However, its tannoid contents increased by 6.4 times. 3) Lager fermentation; The final alcohol content was 5.93% (ABV). The effect of GTE on lager beer was minimal for all variables. However, total polyphenol of GTE beer increased by 1.4 times (p < .05). Its tannoid increased by 3.3 times (p < .05).

모형 그물에 대한 어군행동의 수직 모델링에 관한 연구 - 해산어에 의한 수치 모델의 적합성 검토 - (A Study on the Numerical Modeling of the Fish Behavior to the Model Net - Fitness Examination of Numerical Model by the Marine Fish -)

  • 장호영;이주희
    • 수산해양기술연구
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    • 제34권2호
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    • pp.174-184
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    • 1998
  • In order to accumulate fundamental. data for control of fishes’ behavior at the real fishing ground, the fitness of the numerical model for describing the behavior of fishes was examined by the marine fish. Mullet, Mugil cephalus were used as experimental fishes. The numerical model of fishes’ behavior presented in our earlier paper was modified on the vertical movement of fish school. For the comparision of parameters of the modified numerical model between mullet and rainbow trout, the estimated values of parameters were identified with dimension. The fitness of the modified numerical model was examined by the comparision between experiment and simulation on the several indexes represented by fishes’ swimming characteristics. The obtained result are summarized a follows : 1. The non-dimensional parameter a’ of propulsive force and kb’ of interactive force by the experiment without model net showed a similarity, but the non-dimensional parameter k sub(c’) of schooling force for rainbow trout was lager than one for mullet and the non-dimensional parameter k sub(w’) of repulsive force for mullet was lager than one for rainbow trout. 2. The non-dimensional parameter a’ and k sub(b’) for rainbow trout by the experiment with model net were a little lager than ones for mullet, but non-dimensional parameter k sub(c’) and k sub(w’) for mullet were lager than ones for rainbow trout. 3. The non-dimensional parameter k sub(c’) and k sub(b’) showed the largest and the smallest value among the non-dimensional parameters for rainbow trout and mullet, respectively. 4. The fitness of the modified numerical model was confirmed by means of the compulsion between experiment and simulation on the swimming trajectory of fishes, the mean distance of individual from wall, the mean swimming speed, the mean swimming depth and the mean distance between the nearest individuals. Especially, the similarity of mean swimming depth was improved by using the modified numerical model.

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방진구에 의한 표면파 산란해석 (A Study on Screening of Surface Waves by Trenches)

  • 김희석;이상진;이종세
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2004년도 봄 학술발표회 논문집
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    • pp.235-242
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    • 2004
  • In this study numerical and experimental studies are conducted to examine the wave screening effectiveness of trenches. The numerical study is based on a finite element model of a "sandbox" with Lysmer-Kuhlemeyer-type absorbing boundaries. Using the model, the screening effectiveness of trench is studied for different trench dimensions and distance from source and receiver to trench. The results of the numerical modeling are compared with the results of the ultrasonic experiment which is performed on a acrylic block with a drilled rectangular cut. These results show that the screening effectiveness of the trench is nearly equal if the depth of trench is lager than 60 % of the surface wave length. If is also shown that if the distance between the trench and the source is lager than twice the surface wave length, the thickness of the trench does not affect the screening effectiveness.

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Ge 농도에 따른 SGOI MOSFET의 전기적 특성 (Electrical characteristics of SGOI MOSFET with various Ge mole fractions)

  • 오준석;김민수;정종완;이영희;정홍배;조원주
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 하계학술대회 논문집
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    • pp.101-102
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    • 2009
  • SGOI MOSFETs with various Ge mole fractions were fabricated and compared to the SOI MOSFET. SGOI MOSFETs have a lager drain current and higher effective mobility than the SOI MOSFET as increased Ge mole fractions. The lattice constant difference causes lattice mismatch between the SiGe layer and the top-Si layer during the top-Si layer growth. However, SGOI MOSFETs have a lager leakage current at subthreshold region. Also, leakage current at subthreshold region increased with Ge mole fractions. This is attributable to the crystalline defects due to the lattice mismatch between the SiGe layer and the top-Si layer.

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Cu Oxide와 Silicon Tip 사이의 나노트라이볼러지 작용 (Nanotribological Behavior of Cu Oxide and Silicon Tip)

  • 김태곤;김인권;박진구
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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    • pp.364-365
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    • 2005
  • This paper report nanotribological behavior between Si tip and Cu wafer surfaces which was treated various concentration of $H_2O_2$. This experimental approach has proven atomic level insight into Cu CMP. It has been used to study interfacial friction and adhesion force between Si tip and Cu wafer surfaces in air by atomic force microscopy (AFM). Adhesion force of Cu surfaces which was pre-cleaned in diluted HF solution was lager than Cu oxide surfaces. Adhesion force of Cu oxide surface was saturated around 7 nN. Slope of normal force vs lateral signal was increased as increasing concentration of $H_2O_2$ and it was saturated around 24. Friction force of Cu oxide was lager than Cu.

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국내 포유동물에 적합한 생태통로의 유형과 규격 (The Suitable Types and Measures of Wildlife Crossing Structures for Mammals of Korea)

  • 최태영;양병국;우동걸
    • 환경영향평가
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    • 제21권1호
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    • pp.209-218
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    • 2012
  • In this study, suitable types and measures of Wildlife Crossing Structures (WCS) for mammals of Korea were analyzed to suggest basic information for design guidelines of WCS. In order to find the types and measures, we conducted field surveys on 79 WCS and literature reviews on 159 WCS. The results of our study were as follows; Small-medium sized carnivores usually use all measures of wildlife underpass, meanwhile large sized herbivores as water deer need lager measures than 0.7 Openness Index(OI). Furthermore, we found that wildlife overpasses were usually used at the measure of 6.8 m width by every mammal. Therefore, we concluded that the proper measures should be lager than 0.7 OI for underpass and 7 m width for overpass.

중심코어를 가지는 저층 철근콘크리트 필로티 건물의 내진성능 (Seismic Performance of Low-rise Piloti RC Buildings with Concentric Core)

  • 윤태호
    • 한국산업융합학회 논문집
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    • 제25권4_2호
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    • pp.611-619
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    • 2022
  • In this study, the seismic performance of low - rise piloti buildings with concentric core (shear wall) position is analysed and reviewed based on KDS 41. The prototype is selected among the constructed low - rise piloti buildings with concentric core designed based on KBC 2005 which was used for many low - rise piloti buildings construction. The seismic performance of the building shows plastic behavior in X-direction and elastic behavior in Y-direction. The inter-story drift is lager than that of concentric core case and is under the maximum allowed drift ratio. The displacement ratio of first story is much lager the that of upper stories, and the frame structure in the first story is evaluated as vulnerable to lateral force. Therefore, low - rise piloti buildings with concentric core need the diminishment of lateral displacement and reinforcement of lateral resistance capacity in seismic design and seismic retrofit.

한국산 맥주성분에 관한 연구 (제 1 ) "Total carbohydrates, amino acids 및 peptides 의 정 에 관하여" (Studies on analysis of the Korean lager beers. (I) "On the estimation of total carbohydrates, amino acids and peptides")

  • 한홍의;김종협
    • 미생물학회지
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    • 제6권2호
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    • pp.63-67
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    • 1968
  • Total carbohydrates, amino acids and peptide-like substances in two kinds of Korean lager beers have been analyzed by the calorimetric method of Dreywood's anthrone reagent and Fowden's ninhydrin reagent. The samples were fractionated with column of ion-exchange resin. The experimental results are as follows; 1. Amounts of non-hydrolyzed carbohydrates in the part of column processed is 1. 82% and 1. 96 % (the value was measured by Bertrand's method). But the amounts of those measured by Dreywood's anthrone method are 5.57% and 4.25%, this values are much more than those of Bertrand's method. 2. It can be estimated the amounts of gum and dextrin are 3.75% and 3.30% in both two beers, by comparison of samples with the above mentioned two method. 3. The amounts of carbohydrates by anthrone reagent in acid-hydrolyzed beers are much increased than those of non-hydrolyzed, so it is suggested the presence of polymer carbohydrates which couldn't be detected by Bertrand's method. 4. Total amounts of amino acids are 0.015% and 0.025% (as glycine) in non-hydrolyzed beers measured by ninhydrine color reaction method, on the other hand the amount of amino acids in acid hydrolyzed beers are 0.06% and 0.056%, this is much more than those of nonhydrolysis. The different amounts means that of peptide-like substances. 5. It is necessary to determine the constituent of amino acid for the better taste of beer, and also it is desirable to check the role of carbohydrates in the course of fermentation, mashing and on lager beer for effective utilization of carbohydrate materials to eliminate the losses.

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Level Crossing과 DPCM을 사용한 유성음/무성음/묵음의 분류 (Voiced/Unvoiced/Silence Classification of Speech Signal by Level Crossing and DPCM)

  • 김진영;성굉모
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(II)
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    • pp.1615-1618
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    • 1987
  • 시간 영역에서 만들어진 음성신호의 파라미터을 이용하여 주어진 음성신호의 구간이 유성음, 무성음, 혹은 묵음인지를 분류하는 새로운 알고리듬을 제시하였다. 이에 사용한 파라미터은 구간내에서 샘플링된 값의 절대치 합과 일정한 level 이상의 peak의 합(T-peak), T-peak와 절대치 합의 비 그리고, DPCM의 절대치 합들이다. 이를 파라미터를 이용하여 간단히 유성음/무성음/묵음 구간을 분류 할였다. This paper proposes new algorithm for classifying speech signal frame into voiced, unvoiced, silence frame, using the parameters extracted from time domain behavior of speech signal The parameters used in this paper are absolute magnitude, the sum of peaks lager than reference level (T-peak), the ratio of T-peak to absolute magnitude and the magnitude of signal outputs of DPCM. Using this parameters, speech signal is more easily classified into voiced/unvoiced/silence frame.

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