• 한국기계가공학회지
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• 제14권2호
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• pp.31-37
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• 2015

Recently, mobile phones have become necessary tools for everyday life. In this study, a device that can serve as a separation between a touch panel and an LCD module in a mobile phone was devised for mass repair processes at a smaill business. We used a wire cutting method to separate the bonding plate area between the modules. The device is composed of DC motors and stepping motors that can deliver a precise cutting motion. The motor control system is connected by individual control modules to a CAN network. The developed device showed excellent performance at high temperature conditions.

• 한국음향학회지
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• 제18권6호
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• pp.3-8
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• 1999

본 연구에서는 신호원에 대한 사전 정보 없이 혼합된 신호로부터 잡음 신호만을 선택적으로 제거할 수 있는 새로운 형태의 능동 소음 제거기(Active noise canceller)를 제안한다. 음성신호와 같은 동특성을 갖는 신호의 분리에 효과적으로 사용되는 동적 재귀 신경망(Dynamic recurrent neural network)을 원하는 신호원에 섞인 잡음신호를 분리하여 선택적으로 제거하기 위한 능동 소음 제거기의 전처리기로 이용한다. 능동 소음 제거기는 분리된 잡음 신호에 대한 역위상 신호를 적응적으로 발생함으로써 특정 위치에서 원하는 신호만을 선택적으로 남길 수 있도록 한다. 컴퓨터 시뮬레이션을 통하여 제안된 시스템이 선택적인 소음제거에 효과적임을 보인다.

• 상하수도학회지
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• 제18권4호
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• pp.461-469
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• 2004

This research is to determine the stormwater effects on sewer concentrations by measuring and comparing the flow and pollutant concentrations during dry and rainy periods in the existing BOX type combined sewer pipes. The monitoring was carried out in two sites, which are the Daesachen outfall having PE separation wall in BOX type combined sewer pipes and the Yongunchen outfall not having seperatioin wall. The average flow-weighted BOD concentraion in Yongunchen outfall is 2-fold lower than in Daesachen outfall because of the dilution effect from ravine water. However, the pollutant mass loading is 16 fold higher in Yongunchen outfall than in Daesachen outfall because of more flows. According to the research, the separation wall controls 52% pollutant mass during a storm period (11.5 mm/hr rainfall intensity). Therefore, the Yongunchen combined sewer system (CSS) need separation wall to control and to prevent more pollutant input in stream. In Daesachen area, the maximum sewer flow rate during a storm period measured about 10 fold bigger than average sewer flow during dry periods. Also the concentrations between rainy and dry periods increase approximately 33 fold for BOD and 120 fold for SS. In Yongunchen area, it increases about 9 fold for the maximum flow rate, 18 fold for BOD and 22 fold for SS during a storm. Therefore, the research is concluded that the separation wall between stromwater (or ravine water) and sewage can decrease the dilution effect in CSS and control the pollutant loading.

• 한국초전도ㆍ저온공학회논문지
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• 제25권3호
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• pp.13-17
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• 2023

Magnetic separation technology for small paramagnetic particles has been desired for the volume reduction of contaminated soil from the Fukushima nuclear power plant accident and for the separation of scale and crud from nuclear power plants. However, the magnetic separation for paramagnetic particles requires a superconducting high gradient magnetic separation system applied, hence expanding the bore diameter of the magnets is necessary for mass processing and the initial and running costs would be enormous. The use of high magnetic fields makes safe onsite operation difficult, and there is an industrial need to increase the magnetic separation efficiency for paramagnetic particles in as low a magnetic field as possible. Therefore, we have been developing a magnetic separation system combined with a selection tube, which can separate small paramagnetic particles in a low magnetic field. In the previous technique we developed, a certain range of particle size was classified, and the classified particles were captured by magnetic separation. In this new approach, the fluid control method has been improved in order to the selectively classify particles of various diameters by using a multi-stage selection tube. The soil classification using a multi-stage selection tube was studied by calculation and experiment, and good results were obtained. In this paper, we report the effectiveness of the multi-stage selection tube was examined.

• International Journal of Aeronautical and Space Sciences
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• 제9권1호
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• pp.111-120
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• 2008

A particle image velocimetry (PIV) technique was employed to investigate the effects of blowing jet on the flow characteristics over stationary and pitch-oscillating airfoils. The Reynolds number was $7.84{\times}10^5$ based on the chord length. It was found that for stationary airfoil cases, continuous and pulsating blowing jets successfully reduced separated wake region at high angles of attack. A comparison study of two different types of jet blowing indicated that pulsating jet is more effective than continuous jet for flow separation control. Pulsating leading-edge blowing postpones flow separation and increased stall angle of attack by $2^{\circ}{\sim}3^{\circ}$. For pitch-oscillating airfoil cases, the PIV results showed that blowing jet efficiently delays the separation onset point during pitch-up stroke, whereas it does not prevent flow separation during pitch-down stroke, even at angles of attack smaller than static ones.

• 아동학회지
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• 제29권5호
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• pp.65-78
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• 2008

This study examined whether parental psychological control influences adolescents' depressive feelings through personality features of dependency and self-criticism. Participants were 315 high school students (M=16 years) who completed questionnaires tapping two types of parental psychological control and student personality and depressive symptoms. Both girls and boys perceived equal levels of maternal and paternal separation-anxious psychological control. Boys perceived higher achievement- oriented psychological control of fathers than mothers; girls perceived equal levels of maternal and paternal achievement-oriented control. Structural relations between types of psychological control, personality features, and depressive symptoms were equivalent for both mothers and fathers and for both boys and girls. Results confirmed that separation-anxious and achievement-oriented control have negative effects on adolescents' adjustment through differential pathways; dependency and self-criticism, respectively.

• 한국물환경학회지
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• 제27권1호
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• pp.36-43
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• 2011

This study is selected two points of combined sewer that occurred Fish Kill after first flush, that analyzed generation of pollutants and stream runoff generation of combined sewer overflows (CSOs) as fine weather and rainfall. In addition, this study was to analyze the relationship between CSOs and sediments, to propose measures to reduce the sediment relevant with CSOs and rainfall runoff from entering sewage treatment plants and measures for discharged directly into streams when indicate relatively good water quality after overflow. Sediments in combined sewer system was discharged about 50~80% as overflows during rainfall and we can reduce the amount of the CSOs at least 50% or more if the sewer does not exist in the sediments because of the amount of discharge about the amount of intercept has been investigated by 3~5 times. Because of velocity at sediment interval in sewer is very low, sewage velocity of about 3~5 times as much as it can increase the amount of sediment can be reduced if the separation wall is installed. Effective control of BOD overflow load is respectively 77.5%, 75.8% at first point, second point by the separation wall is installed. Drainage area greater than area in this study or many combined sewer overflows region is increased the more effective control of separation wall. Turbidity to measure changes in water quality of overflows can be used as an factor to control the intercept flows because the intercept flows(3Q) after the first flush has lowered removal efficiency and increases the operational load of sewage treatment plants. Sewage water quality after a overflow when the reasonable turbidity was measured at this point flows to excluded intercept flow(1Q) can be discharged to stream.

• 한국컴퓨터정보학회논문지
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• 제15권1호
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• pp.167-175
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• 2010

임무분리(Separation of Duty: 이하 SoD)는 위임(delegation)과 더불어 접근제어 분야에서 중요한 보안 정책 중의 하나이다. 기존의 역할 기반 접근제어 모델을 기반으로 한 과거 임무분리모델은 역할기반 접근제어 모델의 여러 제한적인 구성 요소(역할계층, 역할계승 등)에 의해 조직 내에서 관리하는 정보의 무결성 침해 가능성에 대한 최소화를 충분히 해결하지 못하고 있다. 본 논문에서는 관리적 역할기반 접근제어 모델인 OS-RBAC 모델과 임무분리 정책을 통합한 조직 구조 기반의 임무분리 관리모델(OS-SoDAM)을 제시한다. OS-SoDAM은 분산 기업 환경의 관리 행위의 범위 기준을 역할 계층과는 구별된 조직 구조로 정의하고 있어 역할계층 및 역할계승에 제한적인 임무분리의 한계를 극복하고 자유롭게 임무분리 정책을 접근제어 모델에 적용할 수 있는 유연성을 제공한다.

• 한국안전학회지
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• 제12권2호
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• pp.22-26
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• 1997

A small scale centrifugal oil separator consisted of two concentric tubes was fabricated for spilt oil recovery. With speed control of the inner tube, its performance of oil separation was investigated. Oil-water mixture is separated by forced vortex motion with the rotating inner tube. Velocity and pressure distributions in the tubes were calculated. Control of rotating speed, which is the most influencing parameter, showed an optimum value 946rpm corresponding to the acceleration of 20g at the inner tube surface. Separation performance was suddenly deteriorated at rotating speed higher than 1200rpm.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.93-98
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• 1991

An improved and flexible matrix algorithm for solving interlinked separation problems which is based on the homotopy continuation method has been developed. A flexible model of the interlinked stream in standardized matrix form and JACOBIAN generation I algorithm for homotopy continuation are suggested. Also DOF analysis is performed for easy-understanding of equation based simulation of complex column systems. The Algorithm is tested on several problems of interlinked separation processes and some of results are documented.