• Journal of Institute of Control, Robotics and Systems
• /
• v.1 no.2
• /
• pp.119-126
• /
• 1995

The purpose of this study is to develop the technique of energy recovery and energy saving by using the optimization of heat exchanger network synthesis. This article proposes a new method of determining the optimal target of a heat exchanger network synthesis problem of which data feature multiple pinch points. The system separation method we suggest here is to subdivide the original system into independent subsystems with one pinch point. The optimal cost target was evaluated and the original pinch rules at each subsystem were employed. The software developed in this study was applied to the Alko prosess, which is an alcohol production process, for the synthesis of heat exchanger network. It was possible to save about 15% of the total annual cost.

• Journal of Sensor Science and Technology
• /
• v.13 no.3
• /
• pp.224-229
• /
• 2004

In this paper, we propose a new Active Noise Control (ANC) system using a teacher forced Blind Source Separation (BSS) algorithm. The Blind Source Separation based on the Independent Component Analysis (ICA) separates the desired sound signal from the unwanted noise signal. In the proposed system, the BSS algorithm is used as a preprocessor of ANC system. Also, we develop a teacher forced BSS learning algorithm to enhance the performance of BSS. The teacher signal is obtained from the output signal of the ANC system. Computer experimental results show that the proposed ANC system in conjunction with the BSS algorithm effectively cancels only the ship engine noise signal from the linear and convolved mixtures with human voice.

• Korean Chemical Engineering Research
• /
• v.54 no.1
• /
• pp.57-63
• /
• 2016

Thermally induced phase separation (TIPS) and nonsolvent induced phase separation (NIPS) were simultaneously induced for the preparation of flat PVDF membranes. N-methyl-2-pyrrolidone (NMP) was used as a solvent and dibutyl-phthlate (DBP) was used as a diluent for PVDF. When PVDF was melt blended with NMP and DBP, crystallization temperature was lowered for TIPS and unstable region was expanded for NIPS. Ratio of solvent to diluent changed the phase separation mechanism to obtain the various membrane structures. Contact mode of dope solution with nonsolvent determined the dominant phase separation behavior. Since heat transfer rate was greater than mass transfer rate, surface structure was formed by NIPS and inner structure was by TIPS. Quenching temperature of dope solution also affected the phase separation mechanism and phase separation rate to result in the variation of structure.

• Korean Journal of Child Studies
• /
• v.29 no.3
• /
• pp.175-189
• /
• 2008

This study examined influences of mothers' attachment experience and separation-anxious psychological control and of adolescents' attachment on adolescents' psychological independence. Participants were 302 high school students (106 boys; 196 girls) and their mothers. Data were collected via questionnaires. Data analyses were by Pearson's correlation and Hierarchical Multiple Regression. Results showed that 1) Mothers' attachment experience with their mothers was positively related to girls' attachment to their mothers; mothers' separation-anxious psychological control was negatively related to adolescents' attachment. 2) Adolescents' attachment to their mothers predicted their emotional and functional psychological independence negatively. 3) Mothers' psychological control was negatively related to functional independence of boys but positively related to emotional independence of both boys and girls.

• Journal of the Institute of Electronics Engineers of Korea TE
• /
• v.39 no.4
• /
• pp.431-436
• /
• 2002

This paper implements an improved model for access control enforcement in enterprise environments. The integration of the task role-based access control model and the "conflicting entities" administration paradigm supply a specification of static and dynamic separation of duty requirements in the workflow environment. The implemented Extended Task Role-Based Access Control model can deal with the conflicting entities for workflow oriented tasks. It will support elaborate separation of duty policy to tasks in enterprise environment through the classification of enterprise sessions according to their characteristics.

• Journal of Power System Engineering
• /
• v.4 no.4
• /
• pp.78-83
• /
• 2000

It is often necessary to observe the working environment of a robot to control it efficiently in the remote location. The remote sensing data and control commands are transmitted via various media such as radio, microwave, and computer network. The World Wide Web can be used as the infrastructure for teleoperation of mobile robots. In this paper we propose an advanced technique of the remote control of mobile robots on the web. For the real-time control, the image separation algorithm is proposed to transmit the current positions of mobile robots instead of transmitting the full frame image. It is shown by experiments that the proposed algorithm is effective.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2012.05a
• /
• pp.527-528
• /
• 2012

DBD (Dielectric Barrier Discharge) plasma actuator was designed for aerodynamic drag reduction using plasma flow control, and the drag reduction was measured by wind-tunnel tests using 2D test model. At the zero wind velocity, the plasma flow control had no effect on the drag reduction because the flow separation and surface friction drag were not occurred. At the wind velocity of 2m/s, 9.7% of drag was reduced by the flow separation control. The drag reduction decreased as the wind velocity increased.

• Journal of Environmental Science International
• /
• v.8 no.2
• /
• pp.263-269
• /
• 1999

For effective $CO_2$ separation using pore size controlled membrane, silica was deposited in the mesopores of a $\gamma$-alumina film by chemical vapor deposition of tetraethoxysilane (TEOS) and phenyl-substituted ethoxysilanes at 773-873K. The membranes prepared with phenyl-substituted ethoxysilanes were calcined to remove the phenyl group and control the pore size. The gas permaselectivity of prepared membranes was evaluated by using $H_2$, $CO_2$ $N_2$, $CH_2$ and $C_3H_8$ single component and a mixture of $CO_2$ and $N_2$. The membranes produced using TEOS contained micropores having permselectivity only to hydrogen, but the phenyl-subsitituted ethoxysilane derived membranes possessed micorpores which are recognizable molecules of $CO_2$, $N_2$ and $CH_4$. In the diphenyl-diethoxysilane-derived membrane, the $CO_2$ permeance and selectivity of $CO_2$/$CH_4$ were $10^{-6} m^3(STP) \cdot m^{-2} \cdot s^{-1} \cdot kPa^{-1}$ and 11, respectively. Therefore, the use of phenyl-substituted ethoxysilane was effective in controlling micropore size for $CO_2$ separation.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2009.05b
• /
• pp.49-52
• /
• 2009

This paper aims to evaluate hydration and intensity property of different kind of members and intensity in order to evaluate compressive strength of structural concrete using Joint Separation Test Body(JSTB). In fact it is difficult to test and evaluate already have constructed member. In this case, common method used by construction engineer is that ; Schmidt rebound hammer test, Ultrasonic pulse test, Method of using test specimen previously cast. However, these method to control the structural intensity involve many problem and impossibility to adapt construction. 80, this paper proposes advance an opinion which have proper to examine intensity. has also aims to examine its validity and the plan to make similar environment with structural concrete and joint separation test body in order to verify efficiency assessment and on-site application.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.10 no.2
• /
• pp.256-263
• /
• 2009

KORAIL carries out an improvement project of railway signaling system for the conventional line from the existing method which permits a train to move within limited speed the ground signal of ATS(Automatic Train Stop) system. The proposed system makes possible that a train can be driven using a speed profile created by onboard signaling system(ATP) with the movement authority from ground balise. A driving test over 100,000km is being executed by developing a tilting train for the speed elevation on the conventional line. And, the introduction of the tilting train by ATP system to the Jung-ang line is expected. However, a speed elevation on a curved line section has a restriction. Therefore, research on safety braking model and train separation control technology for the localization of ATP system is required preferentially. In this paper, we presented a safety braking model of ATP system and a train separation control method that use ground balise as variable information provider, and executed a performance simulation.