• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 2004.04a
• /
• pp.144-148
• /
• 2004

Recently, various studies had been made for automatic control system of small ships, in order to improve maneuvering and to reduce labor and working on board. To achieve efficient operation of small ships, it had accomplished to rapid development of automatic technique, but the ship operation had been more complicated because of the need to handle various gauges and instruments. To solve these problems, there are examples to be applied to the speech information processing technologies which is one of the human interface methods in the system operation of ship, but the implementation of definite system is still incomplete. Therefore, the purpose of this paper is to implement the control system for ship steering using the voice recognition module.

• 제어로봇시스템학회:학술대회논문집
• /
• 2001.10a
• /
• pp.126.4-126
• /
• 2001

Recently, researches on CIM in product lines of industrial plant are widely progressed, automation of working environment with modernization of product equipments is realized and also, installation of integrated control system based on computer is activated. Since the CIM system is basically developed by using computer, there are several complicated problems such as design problem of hardware interface between computer and many product machines with individual special functions, software development problem with realtime data process and multi communication functions for realtime data monitoring and control of product machines This paper shows the development results for a single board type of microcontroller and a monitoring software based on realtime processing database system ...

• 제어로봇시스템학회:학술대회논문집
• /
• 2002.10a
• /
• pp.105.5-105
• /
• 2002

Digital Polymer Motor (DPM) based on dielectric elastomer is presented. It includes all the supplementary parts for actuation such as micro-controller, DC-DC converter etc. DPM can be operated by itself with the program embedded and controlled via serial interface with PC. The actuator accomplishes bidirectional actuation and compliance controllability, which are important characteristics for a biomimetic artificial muscle actuator. DPM accomplish these requirements without any mechanical substitute or complicated algorithms. Its basic concepts and working principles are addressed with modeling and simulation and the compliance controllability are verified by conducting several experiments. $\textbullet$ Polymer, Dielectric, Biomimetic

• 한국전산유체공학회:학술대회논문집
• /
• 2008.03a
• /
• pp.340-346
• /
• 2008

A level-set method is developed for computation of drop motions in various engineering applications. Compared with the volume-of-fluid method based on a non-smooth volume-fraction function, the LS method can calculate an interface curvature more accurately by using a smooth distance function. Also, it is straightforward to implement for two-phase flows in complex geometries unlike the VOF method requiring much more complicated geometric calculations. The LS method is applied to simulation of inkjet process, thin film pattering and droplet collisions.

• 한국전산유체공학회:학술대회논문집
• /
• 2008.10a
• /
• pp.340-346
• /
• 2008

A level-set method is developed for computation of drop motions in various engineering applications. Compared with the volume-of-fluid method based on a non-smooth volume-fraction function, the LS method can calculate an interface curvature more accurately by using a smooth distance function. Also, it is straightforward to implement for two-phase flows in complex geometries unlike the VOF method requiring much more complicated geometric calculations. The LS method is applied to simulation of inkjet process, thin film pattering and droplet collisions.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.9 no.2
• /
• pp.104-109
• /
• 2009

At a lower supply voltage, voltage-mode drivers draw less current than current-mode drivers. In this paper, we newly propose a voltage-mode driver with an additional current path that reduces the output voltage swing without the need for complicated additional circuitry, compared to conventional voltage-mode drivers. The prototype driver is fabriccated in a 0.13-$^{\mu}m$ CMOS technology and used to transmit data streams at the rate of 2.5 Gb/s. Deemphasis is also implemented for the compensation of channel attenuation. With a 1.2-V supply, it dissipates 8.0 mA for a 400-mV output voltage swing.

• 한국전산유체공학회:학술대회논문집
• /
• 1995.04a
• /
• pp.5-29
• /
• 1995

A three-dimensional flow field induced by two trains passing by each other inside a tunnel is studied based on the numerical simulation of the three-dimensional compressible Euler/Navier-Stokes equations formulated in the finite difference approximation. Domain decomposition method with the FSA(fortified solution algorithm) interface scheme is used to treat this moving-body problem. The computed resluts show basic characteristic of the flow field created when two trains passing by each other. History of the pressure distributions and the aerodynamic forces acting on the trains are mailnly discussed. The results indicate that the phenomenon is complicated due to the interaction of the flow induced by two trains. Strong side force occurs between the two trains when the front portion of the opposite train passes by. It fluctuates rapidly and maximum suction force occurs when two trains are aligned side by side. The results also indicate the effectiveness of the present numerical method for moving boundary problems.

• 한국전산유체공학회:학술대회논문집
• /
• 2005.04a
• /
• pp.123-127
• /
• 2005

The numerical analyses of the complicated flows are widely attempted in these days. Because of the enormous demanding memory and calculation time, parallel processing is used for these problems. In order to obtain calculation efficiency, it is important to choose proper domain decomposition technique and numerical algorithm. In this research we enhanced the efficiency of the CFDS code developed by ADD, using parallel computation and newly developed numerical algorithms. For the huge amount of data transfer between blocks non-blocking method is used, and newly developed data transfer algorithm is used for non-aligned block interface. Recently developed RoeM scheme is adpoted as a spatial difference method, and AF-ADI and LU-SGS methods are used as a time integration method to enhance the convergence of the code. Analyses of the flows around the ONERA M6 wing and the high angle of attack missile configuration are performed to show the efficiency improvement.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.30 no.2 s.245
• /
• pp.112-119
• /
• 2006

Due to their intrinsic anisotropy, composite materials show quite complicated damage mechanism with their fiber orientation and stacking sequence and especially, their fatigue damage process is sequential occurrence of matrix cracking, delamination and fiber breakage. In the study, to propose new model capable of describing damage mechanism under fatigue loading, fatigue analysis of composite laminates based on damage mechanics, are performed. The average stress is disassembled with stress components of matrix, fiber and interlaminar interface through stress analysis. Each stress components are used to assess static damage analysis based on continuum damage mechanics (C.D.M.). Fatigue damage curves are obtained from hysteresis loop and assessed by the fatigue damage analysis. Then, static and fatigue damage analysis are combined. Expected results such as stress-cycle relation are verified by the experimental results of fatigue tests.

• 한국전산유체공학회:학술대회논문집
• /
• 2007.04a
• /
• pp.95-98
• /
• 2007

A general purpose program NUFLEX has been extended for two-phase flows with topologically complex interface and cavitation flows with liquid-vapor phase change caused by large pressure drop. In analysis of two-phase flow, the phase interfaces are tracked by employing a LS(Level Set) method. Compared with the VOF(Volume-of-Fluid} method based on a non-smooth volume-fraction function, the LS method can calculate an interfacial curvature more accurately by using a smooth distance function. Also, it is quite straightforward to implement for 3-D irregular meshes compared with the VOF method requiring much more complicated geometric calculations. Also, the cavitation process is computed by including the effects of evaporation and condensation for bubble formation and collapse as well as turbulence in flows. The volume-faction and continuity equations are adapted for cavitation models with phase change. The LS and cavitation formulation are implemented into a general purpose program for 3-D flows and verified through several test problems.