최대진폭의 Fluctuation에 의한 유성음구간 Explicit 검출

鄭英暢,裵明振 湖西大學校工業技術硏究所 1989 工業技術硏究所論文集 Vol.8 No.-

Accurate detection of the voiced segment in speech signals is important for robust pitch extraction. This paper describes an explicit detection algorithm for detecting the voiced segment in speech signals. This algorithm is based on the fluctuation properties of maximum magnitudes in each frame of speech signals. The performance of this detector is evaluated and compared to that obtained from manually classifying 150 recorded digit utterances.

Ceramic Heater의 特性에 관한 硏究

鄭英暢,許敏旭 湖西大學校 工業技術硏究所 1991 工業技術硏究所論文集 Vol.10 No.-

The objectives of this study are to find out the characteristics of the ceramic heater, and to utilize them in developing other kind of semicoductor that will be used as heating materials. The characteristics of the current-voltage in P. T. C. are in accorance with the change of hyperbolic curves, and the characteristics of the voltage-temperature are saturated and equilibrated at 60[V]- 70[V]. About two minutes later, the ceramic heater operates normally as a heater. The ceramic heater is consmed with less power than any other kind of the heater. However, the effect of heat in the heater is as much as othc heaters, and it is safe enough from a fire caused by over heating. There is no noise and no poisonous gas when the fuel is burning. But, the cell of ceramic is not so easy to manufacture, and that is the problem we have to solve in the future.

매설 열배관의 열팽창 처리방법 비교

정영창,Jeong, Yeong-Chang 한국플랜트학회 2006 플랜트 저널 Vol.2 No.4

신경회로망을 이용한 휴대용 전자 혀 시스템의 설계

정영창(Jung, Young-Chang),김동진(Kim, Dong-Jin),김정도(Kim, Jeong-Do),정우석(Jung, Woo-Suk) 한국산학기술학회 2005 한국산학기술학회논문지 Vol.6 No.2

본 논문은 이온 선택성 전극을 모듈화한 MACS를 사용하여 시스템의 크기를 축소할 수 있었고, PDA를 사용함으로써 측정된 데이터를 장소에 구애받지 않고 분석할 수 있는 휴대용 전자혀 시스템을 개발하였다. MACS는 NH₄⁺, Na⁺, CI⁻, N03⁻, K⁺, Ca2⁺, Na⁺, pH의 7종의 이온 선택성 전극을 이용하여 구성하였으며, 초기화 및 교정과정과 완충용액에 의한 안정화 과정을 거친 후 MACS로 시료에 대한 각각의 이온선택성 전극의 변화를 측정한다. 이렇게 각 전극으로부터 측정된 데이터를 이용하여 신경회로망 알고리즘으로 측정된 시료의 종류를 구분할 수 있다. 실험은 분류가 어렵다고 알려진 고급양주와 저급양주를 분류하는 것으로 진행되었으며, 성공적이며 우수한 설험 결과를 얻었다. 이로부터 사용된 알고리즘이 휴대용 전자혀 시스템에 적절히 사용될 수 있음을 밝혔으며, 설제 휴대용 전자혀 시스템에 간단한 학습에 의해 적용될 수 있을 것으로 생각된다. In this paper, we have designed and implemented a portable e-tongue (electronic tongue) system using MACS (multi array chemical sensor) and PDA. The system embedded in PDA has merits such as comfortable user interface and data transfer by internet from on-site to remote computer. MACS was made up 7 electrodes (NH₄⁺, Na⁺, Cl⁻, N03-, K⁺, Ca2⁺, Na⁺ pH) and a reference electrode. For learning the system, we adapted the Levenberg-Marquardt algorithm based on the back-propagation, which could iteratively learned the pre-determined standard patterns, in etongue system. Conclusionally, the relationship between the standard patterns and unknown pattern can be easily analyzed. The e-tongue was applied to whiskeys and cognac (one high level whisky, one low level whiskey, two cognac) and 2 sample whiskeys for each standard patterns and unknown patterns. The relationship between the standard patterns and unknown patterns can be easily analyzed.

디지탈 회로의 雑音에 関한 研究

鄭英暢 호서대학교 사회과학연구소 1981 社會科學硏究 Vol.1 No.1

本 論文은 Digital Circuit에 있어서 発生하는 여러가지 雑音중 電源, 接地, 誘導, 反射 및 静電気와 雑音과의 관계를 밝혀보고 또한 그의 防止는 어떠한 方法이 있는가에 대해 알아보며 많은 문제점이 있는 이 分野에 더욱 研究가 要望된다.

실리콘의 펠티에 효과에 對한 硏究

鄭英暢(Young Chang Jung) 호서대학교 사회과학연구소 1985 社會科學硏究 Vol.4 No.1

Being that the melting point of silicon is 1800 J/gr, in this paper it is interested that Si-Semiconductors will be worth using of Peltier effect. For attachment of semiconductor chips, a cure schedule of 2 hours at 200°C has been found to yield a stable and reliable. In the results, it is a semi-permant element and using with a heating element the temperature is up to 200°C over. At the end, it will be possible to improve an excellent elements with a way.

인공신경망을 이용한 BTX 농도 측정에 관한 연구

정영창,김동진,홍철호,이장훈,권혁구 한국산학기술학회 2004 한국산학기술학회논문지 Vol.5 No.1

휘발성유기 화합물(Volatile Organic Compounds: VOCs)은 탄화수소 화합물을 총칭한다. 이는 오존 및 광화학 스모그의 원인물질일 뿐 아니라 인체에는 암을 유발시키는 유해 물질이다. 또한 대기 중 악취 물질로서 환경 및 건강에 영향을 초래하는 유해성 물질이다. 본 논문은 대기 중에 포함된 암을 유발시키는 유해성 물질인 BTX(Benzene, Toluene, Xylene)의 존재 유무와 농도 측정에 대해서 연구하였다. 다종의 가스센서를 어레이하여 BTX 가스를 측정하고 인공신경망(Artificial Neural Network ANN)의 역전파(Back propagation : BP) 알고리즘으로 시뮬레이션과 실험을 통해 농도를 추론하였다. ANN 모듈은 기준 데이터를 시뮬레이션을 통해 학습시키고, 가스를 주입하여 실험 할 때 학습된 델타 모델에 근거하여 추론을 할 수 있는 추론 알고리즘 모듈이다. 이 모듈은 기준데이터를 MATLAB 코드로 시뮬레이션을 하여 생성된 parameter를 가지고 수행했으며, 시뮬레이션 결과를 실험을 통해 비교 테스트하여 검증하였다. Air quality monitoring is a primary activity for industrial and social environment. Especially, the VOCs(Volatile Organic Compounds) are very harmful for human and environment. Throughout this research, we designed sensor array with various kinds of gas sensor, and the recognition algorithm with ANN (Artificial Neural Network : BP), respectively. We have designed system to recognize various kinds and quantities of VOCs, such as benzene, toluene, and xylene.

실리콘의 펠티에 효과에 對한 硏究

鄭英暢 湖西大學校工業技術硏究所 1985 工業技術硏究所論文集 Vol.4 No.-

Being that the melting point of silicon is 1800 J/gr, in this paper it is interested that Si-Semiconductors will be worth using of Peltier effect. For attachment of semiconductor chips, a cure schedule of 2 hours at 200℃ has been found to yield a stable and reliable. In the results, it is a semi-permant element and using with a heating element the temperature is up to 200℃ over. At the end, it will be possible to improve an excellent elements with a way.

Characteristics of woodland changes in an agricultural landscape - The case of Gwangju

이영창,정운주,김근호,Lee, Young-Chang,Jung, Woon-Joo,Kim, Keun-Ho Institute of Agricultural Science 2011 Korean Journal of Agricultural Science Vol.38 No.3

Recent landscape changes from human activities, such as agricultural development and urbanisation frequently result in the loss of habitats, the reduction in habitat patch size and an increasing isolation of habitat patches. However, there is little information on woodland changes in agricultural landscapes. Therefore, the aim of this research was to assess spatial characteristics and changes of woodland in an agricultural landscape and how these may have had an impact on ecological process for 33 years. One of the agricultural landscape character units was analysed based on aerial photographs from 1976, 1983, 1994, 2002 and 2009 in Gwangju city. The results indicated that landscape ecological metrics clearly showed that they could be used to monitor changes of woodland ecological conditions during the past 33 years. The results imply that particularly human activities have been leading to the decrease of the mean size of woodland patches and finally result in woodland isolation. These changes may have a negative impact on woodland bird species in the study area. This woodland information can be used to identify the potential and specific needs for setting priorities for conservation planning.

Characteristics of woodland changes in an agricultural landscape

이영창(Young-chang Lee),정운주(Woon-joo Jung),김근호(Keun-Ho Kim) 충남대학교 농업과학연구소 2011 농업과학연구 Vol.38 No.3

Recent landscape changes from human activities, such as agricultural development and urbanisation frequently result in the loss of habitats, the reduction in habitat patch size and an increasing isolation of habitat patches. However, there is little information on woodland changes in agricultural landscapes. Therefore, the aim of this research was to assess spatial characteristics and changes of woodland in an agricultural landscape and how these may have had an impact on ecological process for 33 years. One of the agricultural landscape character units was analysed based on aerial photographs from 1976, 1983, 1994, 2002 and 2009 in Gwangju city. The results indicated that landscape ecological metrics clearly showed that they could be used to monitor changes of woodland ecological conditions during the past 33 years. The results imply that particularly human activities have been leading to the decrease of the mean size of woodland patches and finally result in woodland isolation. These changes may have a negative impact on woodland bird species in the study area. This woodland information can be used to identify the potential and specific needs for setting priorities for conservation planning.