단보 : 국내 전통누룩에서 분리한 증류식 소주용 효모의 특성

최한석 ( Hanseok Choi ),강지은 ( Jieun Kang ),정석태 ( Seoktae Jeong ),김찬우 ( Chanwoo Kim ),( Kazunori Takamine ) 한국균학회 2015 韓國菌學會誌 Vol.43 No.3

본 연구에서는 국내 전통누룩에서 분리한 증류식 소주용 효모의 생리적 특성을 조사하고 동정하였다. 분리균(N4)의 26S rDNA-D1/D2 염기배열은 Saccharomyces cerevisiae 표준균주(NRRL Y-12632)와 100% 상동성을 나타내었고 다 극출아에 의해서 증식하였다. Glucose, galactose, maltose, sucrose를 발효할 수 있으며 trehalose, raffinose, methylglucoside를 자화할 수 있었다. 40℃ 이상에서는 증식하지 못했으며 50% glucose와 10% NaCl 농도에서 성장할 수 있었다. 염기배열, 형태관찰 및 생리적 특성을 종합하여 분리균을 S. cerevisiae로 동정하였다. The occurrence and characterization of yeast isolated from Korean traditional nuruk were investigated. Sequences of the D1/D2 domain of the 26S rDNA were identical for a strain examined and had a similarity value of 100% compared to sequences of the type strain of Saccharomyces cerevisiae (NRRL Y-12632). The isolate able to assimilate with trehalose, raffinose, and methyl-glucoside assimilate was also capable of glucose, galactose, maltose, and sucrose fermentation. It did not proliferate at 40oC or above, but was able to grow in concentration of 50% glucose and 10% NaCl. By combining nucleotide sequence, morphological observation, and physiological characteristics, the isolate was identified as S. cerevisiae.

Finding the optimal route of the subway systemusing context-aware

Hanseok Lee,Nam Gyu Kim,Kyong Joo Oh,Jaeyoung Choi 대한산업공학회 2007 대한산업공학회 추계학술대회논문집 Vol.2007 No.11

간섭신호의 영향에 따른 WLAN 서비스품질 측정

김한석(Hanseok Kim),최재훈(Jaehoon Choi),노정민(Jeongmin Noh),송대원(Daewon Song),이상엽(Sangyeob Lee),김근배(Geunbae Kim) 한국통신학회 2023 韓國通信學會論文誌 Vol.48 No.12

메탄/순산소 예혼합 화염의 선회특성

김한석(Hanseok Kim),최원석(Wonseok Choi),조주형(Juhyeong Cho),안국영(Kookyoung Ahn) 대한기계학회 2009 大韓機械學會論文集B Vol.33 No.5

The present study has experimentally investigated the effects of CO₂ diluted oxygen on the structure of swirl-stabilized flame in a lab-scale combustor. The methane fuel and oxidant mixture gas (CO₂ and O₂) were mixed in a pre-mixer and introduced to the combustor through different degrees of swirl vanes. The flame characteristics were examined for various amount of carbon dioxide addition to the methane fuel and various swirl strengths. The effects of carbon dioxide addition and swirl intensity on the combustion characteristics of pre-mixed methane flames were examined using chemiluminescence techniques to provide information about flow field. The results show that the hot combustion zone increases at the upstream reaction zone because of an increase in the recirculation flow for an increase in swirl intensity. The hot combustion zone is also increased at the downstream zone by recirculation flow because of an increase in swirl intensity which results in higher centrifugal force. The OH and CH radical intensities of reaction zone decrease with carbon dioxide addition because the carbon dioxide plays a role of diluted gas in the reaction zone.

Fruit and Brandy Liquor Quality on Ripening Time of Grape Cultivar

Eugene Kim,Hanseok Choi,Seoktae Jeong,Jiho Choi,Jieun Kang 한국식품영양과학회 2014 한국식품영양과학회 학술대회발표집 Vol.2014 No.10

Acoustic and visual signal based context awareness system for mobile application

Woo-Hyun Choi,Seung-Il Kim,Min-Seok Keum,Han, David K.,Hanseok Ko IEEE 2011 IEEE transactions on consumer electronics Vol.57 No.2

<P>In this paper, an acoustic and visual signal based context awareness system is proposed for a mobile application. In particular multimodal system is designed that can sense and determine, in real-time, user contextual information, such as where the user is or what the user does, by processing acoustic and visual signals from the suitable sensors available in a mobile device. A variety of contextual information, such as babble sound in cafeteria, user¿s movement, and etc., can be recognized by the proposed acoustic and visual feature extraction and classification methods. We first describe the overall structure of the proposed system and then the algorithm for each module performing detection or classification of various contextual scenarios is presented. Representative experiments demonstrate the superiority of the proposed system while the actual implementation of the proposed scheme into mobile device such as a smart-phone confirms the effectiveness and realization of the proposed system.</P>

메탄/순산소 예혼합 화염의 선회 특성

최원석(Wonseok Choi),김한석(Hanseok Kim),조주형(Joohyeong Cho),김용모(Yongmo Kim),안국영(Kookyoung Ahn),우타관(Takwan Woo) 대한기계학회 2008 대한기계학회 춘추학술대회 Vol.2008 No.11

The effects of carbon dioxide addition to oxygen have been investigated with swirl-stabilized premixed methane flame in a laboratory-scale pre-mixed combustor. The methane fuel and oxydant mixture gas (CO₂ and O₂) were mixed in a pre-mixer and introduced to the combustor through different degrees of swirl vanes. The flame characteristics were examined for different amount of carbon dioxide addition to the methane fuel and different swirl strengths. The effects of carbon dioxide addition and swirl intensity on the combustion characteristics of pre-mixed methane flames were examined using chemiluminescence techniques to provide information about flow field. The results show that the flame area increases at upstream of reaction zone because of increase in recirculation flow for increase in swirl intensity. The flame area is also increased at the downstream zone by recirculation flow because of increase in swirl intensity which results in higher centrifugal force. The OH and CH radical intensity of reaction zone decrease with carbon dioxide addition because the carbon dioxide plays a role of dilution gas in the reaction zone.

K-SVD 기반 사전 훈련과 비음수 행렬 분해 기법을 이용한 중첩음향이벤트 검출

최현식,금민석,고한석,Choi, Hyeonsik,Keum, Minseok,Ko, Hanseok 한국음향학회 2015 韓國音響學會誌 Vol.34 No.3

비음수 행렬 분해(Nonnegative Matrix Factorization, NMF) 기법은 사전행렬과 크기성분을 번갈아 가며 업데이트 하면서 구하는 방법이며 직관적 해석 및 구현의 용이성으로 인해 중첩음향이벤트 분리 및 검출방법으로 널리 활용되었다. 하지만 비음수 행렬 분해의 고유한 특성인 부분기반표현(part-based representation)으로 인해 하나의 음향 이벤트를 구성 하는 사전(dictionary)의 파편화 현상이 발생하고, 다른 음향이벤트와 중복되는 사전이 생성되어 결과적으로 분리, 검출 성능의 저하 문제가 발생한다. 본 논문에서는 사전 획득 단계의 부분기반표현에 의한 문제를 해소하기 위해 K-Singular Value Decomposition(K-SVD)을 사용하여 사전을 획득하고, 음향이벤트 검출 단계 에서는 기존 비음수 행렬 분해 기법을 이용하여 크기를 획득 한다. 제안하는 방식을 통해 비음수 행렬 분해 기반의 사전을 사용하는 경우보다 중첩음향이벤트 검출 성능이 개선되는 것을 확인하였다. Non-Negative Matrix Factorization (NMF) is a method for updating dictionary and gain in alternating manner. Due to ease of implementation and intuitive interpretation, NMF is widely used to detect and separate overlapping sound events. However, NMF that utilizes non-negativity constraints generates parts-based representation and this distinct property leads to a dictionary containing fragmented acoustic events. As a result, the presence of shared basis results in performance degradation in both separation and detection tasks of overlapping sound events. In this paper, we propose a new method that utilizes K-Singular Value Decomposition (K-SVD) based dictionary to address and mitigate the part-based representation issue during the dictionary learning step. Subsequently, we calculate the gain using NMF in sound event detection step. We evaluate and confirm that overlapping sound event detection performance of the proposed method is better than the conventional method that utilizes NMF based dictionary.

가정용 연료전지 막 가습기 해석 모델 개발

유상석(Sangseok Yu),김한석(Hanseok Kim),이상민(Sangmin Lee),이영덕(Youngduk Lee),최원석(Wonseok Choi),안국영(Kookyoung Ahn) 대한기계학회 2008 대한기계학회 춘추학술대회 Vol.2008 No.5

The performance of proton exchange membrane fuel cell (PEMFC) is seriously changed by the humidification condition which is intrinsic characteristics of the PEMFC. Typically, the humidification of fuel cell is completed by internal or external humidifier. A membrane humidifier is applied to the external humidification of fuel cell used for residential power generation. In this study, a simple static model is constructed to understand the physical phenomena of the membrane humidifier over various parameters. The model is based on the concept of shell and tube heat exchanger but the model is also able to estimate the mass transport through the membrane. Model is constructed in Matlab/Simulink<SUP>®</SUP>□environment to keep consistency with any other components model which we developed. Parametric study of the membrane humidifier is carried out in terms of selected geometric factors and operating factors.

재발량 분석을 이용한 음향 상황 인지

박상욱,최우현,고한석,Park, Sangwook,Choi, Woohyun,Ko, Hanseok 한국음향학회 2016 韓國音響學會誌 Vol.35 No.1

동일한 장소에서도 매우 다양한 음향이 발생하고, 서로 다른 장소에서도 유사한 음향이 발생하기 때문에 훈련 데이터가 적거나, 훈련 단계에서 일부 음향만 고려된 경우 음향 상황 인지 성능을 보장할 수 없다. 이러한 문제점을 해결하기 위한 방법으로 Bag of Words (BOW) 기반 히스토그램 특징이 소개되었다. 하지만 BOW 기반 히스토그램 특징은 일정 시간동안 발생한 음향의 분포를 이용하기 때문에 음향이 발생한 순차적인 정보는 고려할 수 없다. 음향 상황 인지에서 일정 시간 동안 발생한 음향의 주기성과 지속성은 상황을 인지하는데 중요한 정보가 될 수 있다. 따라서 본 논문에서는 재발량 분석을 이용하여 주기성과 지속성에 대한 특징을 추출하였다. 인식 실험에서 재발량 분석을 통해 추출된 특징을 함께 사용한 경우 기존 방법들 보다 향상된 성능을 확인했다. Since a variety of sound occur in same place and similar sound occurs in other places, the performance of acoustic scene classification is not guaranteed in case of insufficient training data. A Bag of Words (BOW) based histogram feature is foreseen as a method to overcome the problem. However, since the histogram features is made by using a feature distribution, the ordering of sequence of features is ignored. A temporal information such as periodicity and stationarity are also important for acoustic scene classification. In this paper, temporal features about a periodicity and a stationarity are extracted by using a recurrent quantification analysis. In the experiment, performance of the proposed method is shown better than other baseline methods.