Vapor Bubble Nucleation : A Microscopic Phenomenon

곽호영 대한기계학회 2004 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.18 No.8

In this article, vapor bubble nucleation in liquid and the evaporation process of a liquid droplet at its superheat limit were discussed from the viewpoint of molecular clustering (molecular cluster model for bubble nucleation). For the vapor bubble formation, the energy barrier against bubble nucleation was estimated by the molecular interaction due to the London dispersion force. Bubble nucleation by quantum tunneling in liquid helium under negative pressure near the absolute zero temperature and bubble nucleation on cavity free micro heaters were also presented as the homogenous nucleation processes.

반려동물용 BCG 센싱 데이터에서 호흡 및 맥박 신호를 분리하는 방법

곽호영,장진욱,김수균,송우진,윤영민 한국컴퓨터정보학회 2022 韓國컴퓨터情報學會論文誌 Vol.27 No.2

Currently, as the number of families living with companion animals increases, the demand for information about the health status of companion animals has increased. As the demand for this increases, there is a need for a method to measure respiration and pulse in companion animals. Considering the characteristics of hairy companion animals, we want to measure respiration and pulse signals using BCG, which is different from adsorption ECG. Since this BCG method is made by mixing respiration and pulse signals into one signal, it is necessary to separate the respiration signal waveform and the pulse signal waveform from one signal waveform. In this paper, a wearable device for BCG measurement was implemented to measure the signal, and a method of separating the signal input from the BCG wearable device into a respiration signal and a pulse signal was proposed. 현재 반려동물과 함께 사는 가정이 매우 늘어나면서 반려동물의 건강 상태에 대해서 알고 싶어하는 요구가 늘었다. 이에 대한 요구의 증가에 따라 반려동물에게서 호흡과 맥박을 측정하는 방법이 필요한데 반려동물의 특성상 털이 있다는 것을 고려하여 흡착식의 심전도와는 다른 방법인심탄도 방식을 이용하여 호흡과 맥박 신호를 측정하고자 한다. 이 심탄도 방식은 호흡과 맥박 신호가 하나의 신호에 섞여 만들어지기 때문에 하나의 신호 파형에서 호흡 신호 파형과 맥박 신호파형을 분리할 필요가 있다. 본 논문에서는 심탄도 측정을 위한 웨어러블 기기를 구현하여 신호를 측정할 수 있게 하고, 이 심탄도 웨어러블 장치로부터 입력된 신호를 호흡 신호와 맥박 신호로 분리하는 방법을 제안하였다.

누룩(Rhizopus oryzae KSD-815)으로부터 분리한 지질화합물의세포독성 및 항염증 활성

곽호영,이상진,이대영,배낙현,정낙훈,홍성렬,김계원,백남인 한국응용생명화학회 2008 Journal of Applied Biological Chemistry (J. Appl. Vol.51 No.2

Nuruk is the Korean traditional Koji that contains various microorganisms and has been used to make the traditional fermented foods including alcoholic beverages. Rhizopus oryzae KSD-815 was isolated from the alcohol-fermenting Nuruk used for manufacturing traditional alcohol. In this study, the authors reported the isolation and identification of four lipids from the Nuruk (Rhizopus oryzae KSD-815) that inoculated wheat with Rhizopus oryzae KSD-815. The dried and powdered Nuruk (Rhizopus oryzae KSD-815) were extracted three times at room temperature with 80% aqueous MeOH. The extracts were partitioned with EtOAc, n-BuOH, and water, successively. The EtOAc extract was suspended in 80% MeOH and partitioned repeatedly with n-hexane. From the n-hexane fraction, four lipids were isolated through the repeated silica gel and ODS column chromatographies. According to the results of physico-chemical data including NMR, GC and MS, the chemical structures of the compounds were determined as linolenic acid methyl ester (1), palmitic acid methyl ester (2), linoleic acid (3), palmitic acid (4). Cytotoxicity was evaluated in huamn breast cancer cells, MDA-MB-231 and human hepatocarcinoma, SK-HEP-1 cells using MTT assay. Exposure of compounds 1 and 3 led to a dose-dependent inhibition of cell viability in both cancer cell lines. In addition, treatment of RAW264.7 cells with compound 3 caused inhibition of lipopolysaccharide/interferon-γ-induced nitric oxide production. Nuruk is the Korean traditional Koji that contains various microorganisms and has been used to make the traditional fermented foods including alcoholic beverages. Rhizopus oryzae KSD-815 was isolated from the alcohol-fermenting Nuruk used for manufacturing traditional alcohol. In this study, the authors reported the isolation and identification of four lipids from the Nuruk (Rhizopus oryzae KSD-815) that inoculated wheat with Rhizopus oryzae KSD-815. The dried and powdered Nuruk (Rhizopus oryzae KSD-815) were extracted three times at room temperature with 80% aqueous MeOH. The extracts were partitioned with EtOAc, n-BuOH, and water, successively. The EtOAc extract was suspended in 80% MeOH and partitioned repeatedly with n-hexane. From the n-hexane fraction, four lipids were isolated through the repeated silica gel and ODS column chromatographies. According to the results of physico-chemical data including NMR, GC and MS, the chemical structures of the compounds were determined as linolenic acid methyl ester (1), palmitic acid methyl ester (2), linoleic acid (3), palmitic acid (4). Cytotoxicity was evaluated in huamn breast cancer cells, MDA-MB-231 and human hepatocarcinoma, SK-HEP-1 cells using MTT assay. Exposure of compounds 1 and 3 led to a dose-dependent inhibition of cell viability in both cancer cell lines. In addition, treatment of RAW264.7 cells with compound 3 caused inhibition of lipopolysaccharide/interferon-γ-induced nitric oxide production.

경포부자(Processed Aconitium carmichaeli)로부터 steroid 화합물의 분리 및 동정

곽호영,류하나,이도경,김경태,백남인 慶熙大學校 食糧資源開發硏究所 2007 硏究論文集 Vol.26 No.2

Kyong-Po Buja, the processed Aconitium carmichaeli, was extracted with 80% aqueous MeOH and the concentrated extract was partitioned with EtOAc, n-BuOH and H20. The repeated silica gel and ODS column chromatographies of the EtOAc fraction led to the isolation of two steroids. From the result of physico-chemical data including NMR, the chemical structures of the compounds were determined as β-sitostεrol and daucosterol.

A Method of Dog Recognition using Nose Print and Landmarks

곽호영,윤영민,장진욱,송우진,김수균 한국컴퓨터정보학회 2022 韓國컴퓨터情報學會論文誌 Vol.27 No.2

In this paper, We propose a method for identifying objects by setting inscriptions and landmarks of dogs. The phenomenon of abandoning dogs is on the rise, and the number of abandoned individuals is also rapidly increasing. These abandoned dogs are becoming wild animals, causing a lot of damage to people's daily life, causing serious problems. As a solution to this problem, the animal registration system is being implemented, but there is a phenomenon that some dog owners avoid the registration method that inserts a chip, so the complete registration system is not settled. When registering a dog, removing the avoidance of dog owners will help establish the companion animal registration system. In this paper, we present a technique to identify objects by setting inscriptions and landmarks of dogs so that dog owners can register their dogs in a friendly way to eliminate this avoidance phenomenon. 본 논문은 비문과 반려견의 랜드마크를 설정하여 개체를 식별하는 방법에 대해 제안한다. 최근반려견을 유기하는 현상이 점차 늘어나고 있는 추세이며 유기된 개체 수도 급증하고 있다. 이 유기된 반려견은 야생화가 되어 사람들의 일상생활에 많은 피해를 주고 있어 심각한 문제를 발생시키고 있다. 이에 대한 해결 방법으로 동물등록제가 시행되고 있으나 일부 반려견 주인들은 칩을삽입하는 등록 방법에 대해 기피하는 현상이 있어 완전한 등록제가 정착되지 않고 있다. 반려견을 등록할 때에 반려견주들의 혐오감이나 기피 현상을 제거하는 것이 반려동물등록제를 정착시킬수 있을 것이다. 본 논문에서는 이러한 기피 현상을 없애고 반려견주들이 친근하게 반려견을 등록할 수 있도록 비문과 반려견의 랜드마크를 설정하여 개체를 식별하는 방법을 제안하였다.

3He , 4He액체의 절대 인장 내력 ( Absolute Tensile Strength )

곽호영,유제청 대한기계학회 1990 대한기계학회 춘추학술대회 Vol.- No.-

On the Problem of Microbubble Paradox

곽호영 대한기계학회 1989 대한기계학회 춘추학술대회 Vol.- No.-

Fe-C-O금속액내에서 CO가스의 기포형성 모델

곽호영,이근배 대한기계학회 1988 대한기계학회 춘추학술대회 Vol.- No.-

해설 : 커스크호의 마지막 순간

곽호영,강상우 대한기계학회 2000 기계저널 Vol.40 No.11

진동하는 기포에 있어서의 열적감쇠 ( Thermal Damping )

곽호영,오시덕,홍재호 대한기계학회 1990 대한기계학회 춘추학술대회 Vol.- No.-