http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
구간분할 제어를 이용한 형상기억합금 와이어의 히스테리시스 특성에 관한 연구
정상화,김주환 한국공작기계학회 2007 한국공작기계학회 추계학술대회논문집 Vol.2007 No.-
Shape memory alloy(SMA) is one of artificial actuators used in the anthropomorphic robot hand. It generates displacement by input of heat or electric current on the entire SMA wire. SMA has a prominent strain hysteresis and its phase transition is dependent on temperature, stress and the direction of motion. Conventional control methods of SMA wire use the analogue, approach such as Galerkin method, Preishach method, slide mode, neural fuzzy, etc. The position control of SMA which uses the analogue approach is difficult. In this paper, the hysteresis characteristics of SMA wire using segment control is studied. SMA wire is controled by the digital approach. Thermo-electric module(TEM) which can heat and cold the same surface using the h-bridge circuit is used for segmenting a SMA wire and hysteresis of segmented SMA wire is measured.
구간 분할 제어를 이용한 형상기억합금 와이어의 온도제어에 관한 연구
정상화,김주환,김태호,서호진,박진완 朝鮮大學校 機械技術硏究所 2007 機械技術硏究 Vol.10 No.1
The key technology of robot is the design of the actuator. Particularly breakthroughs of power-to-weight ratio or energy-density III actuator technology have significant impacts upon the design and the control of robotic systems. To realize the anthropomorphic motion, artificial muscles such as shape memory alloy(SMA) and electro active polymer(EAP) are used. These actuators have the higher energy density than the electromechanical actuators such as the electric motor. The EAP has the property of good elasticity, but it is difficult to get the required power. The SMA has the good power density and simple structure, but the control scheme of the actuator is difficult. In this paper, temperature control of SMA wire using segment control is studied. The SMA wire is segmented by thermo-electric module(TEM). To supply constant currents in TEMs, MOSFET is used. Hysteresis in one segment of SMA wire is evaluated. The force and displacement of SMA wire are measured according to the number of segment. The program to control the temperature of TEM is developed by using LabVIEW software.
내식성 첨가물질로서 폴리아날린/금속(산화물) 복합체의 제조
조정환,오영주,최영주 고신대학교 자연과학연구소 2007 고신대학교 자연과학연구소 논문집 Vol.14 No.-
폴리아닐린 합성에는 아닐린 단량체에 파라-툴루엔설폰산(ρ-TSA)과 같은 유기도판트를 사용하였으며, 복합체 제조에는 산화알루미늄, 산화마그네슘 등의 금속 산화물이나 나노사이즈의 아연 분말을 사용하였다. 이렇게 제조한 복합체를 다양한 조성으로 수분산 바인더에 첨가하여 내식성 코팅 물질을 제조하였다. Aniline monomers and ρ-toluenesulfonic acid as a dopant were used to synthesize polyanilines, and metal oxides such as Aluminum oxides, Magnesium oxides, and metal powders such as Zinc and Aluminium were used to prepare polyaniline/metal(oxides) complexes. The coating materials for corrosion protection of metals were prepared by adding the complexes of various ratios into a water soluble binder.
쌍태아에서 제 1태아의 분만 후 제 2태아의 지연분만 : 중례보고
김주환,서민정,유희정,노권일,조대현,박정규,이정헌,조성남,손영수 朝鮮大學校 附設 醫學硏究所 2005 The Medical Journal of Chosun University Vol.30 No.3
With the widespread use of fertility medications and techniques of in vitro fertilization, multiple gestation has become epidemic in modern obstetric practice. Delivery of the initial fetus in a multiple gestation usually is followed by delivery of the subsequent fetus or fetuses shortly thereafter. However in rare circumstances, the delivery is delayed for days due to disappearance of uterine contraction after delivery of the first fetus. When uterine activity ceases after the delivery of the first neonate, a policy of nonintervention may be considered in case of an immature or very premature delivery, in order to achieve a gestational age for the remaining fetus(es) more compatible with neonatal survival. We report a case of twin gestation with prolongation of the delivery interval between the twins for 46 days.
초정밀가공기를 이용한 Zerodur의 연삭 특성에 관한 연구
김주환,김건희,한정열,김석환,원종호 한국공작기계학회 2003 한국공작기계학회 춘계학술대회논문집 Vol.2003 No.-
We explored a new rough grinding technique on optics materials such as Zerodur. The facility used is a NANOFORM-600 diamond turning machine with a custom grinding module and a range of diamond resin bond wheel. The grinding parameters such as workpiece rotation speed, depth of cut and feed rate were altered while grinding the workpiece surfaces of 20mm in diameter. Surface roughness is measured by Form Talysurf series2. Our target is to define grinding conditions producing the surface roughness better than 0.02μm Ra and the form accuracy of around 0.2μm PV.
Gas-Liquid Chromatography를 이용한 사과 및 배 중의 농약 다성분 잔류분석법
박주황,김택겸,오창환,김정한,이영득,김장억 한국환경농학회 2004 한국환경농학회지 Vol.23 No.3
사과 및 배 시료에서 농약 다성분의 gas chromatography를 이용한 잔류분석법 확립을 위하여 199가지의 농약를 선정 하여 retention time 및 검출기에 따라 ECD 5 그룹 및 NPD 5 그룹의 10개 그룹으로 분류하였다. 시료의 종류에 따른 분석조건을 확립하기 위한 회수율 시험은 농약들의 log P_(ow) 값과 화학적 분류에 따라 총 18개 (ECD 11개, NPD 7개)의 농약을 선정하였다. 예비실험 후 확립된 분석방법에 따라 10개 그룹의 혼합 표준용액으로 사과 및 배에 대한 회수율시험을 행하였다. 그 결과, 총 196가지의 농약의 70%에 해당하는 사과에서 136개, 배에서 133개의 농약들에서 회수율 70에서 120%의 양호한 결과를 나타내었다. 그러나 사과에서 43개, 배에서 45개의 농약들이 70% 미만의 회수율을 보였고, fenvalerate는 120% 이상의 회수율을 나타내었으며, 사과에서 17개 및 배에서 18개의 농약들은 검출이 되지 않았다. 그러나 확립된 분석법은 SOP에 의한 신속하고 수월한 수행으로 농산물 중의 잔류농약을 검출 및 모니터링하는 목적에 적합하다고 사료된다. A rapid analytical method was developed to determine multiple pesticide residues in apples and pears using gas-liquid chromatography (GLC). The samples were extracted with water-miscible solvents and purified by cleanup procedures serially comprising liquid-liquid partition and solid-phase extraction (SPE). Each analyte was separated and determined by a high-resolution GLC equipped with electron-capture detector (ECD) and nitrogen-phosphorous detector (NPD). A total of 196 pesticides, which were previously classified into 5 groups each for ECD and NPD based on their retention behaviors on the capillary column and responses to the detector, were subjected to the recovery experiment. In compliance with the analytical criteria, 70 to 120% of recovery and less than 20% relative standard deviation, the proposed method could be successfully applied to analyze 136 and 133 pesticide residues in apples and pears, respectively, which enabled not only rapid screening but quantitation of the residues. Even though less reliability was resulted from unacceptable recovery range, rest of pesticides including 43 and 45 analytes in apples and pears, could be also detected for their identity. The proposed method, failed to cover 17 and 18 pesticides for apples and pears, which mostly showed high polarity or heat-lability but, could be suitable for fast surveilance or monitoring of fruit harvests.