• Journal of Ocean Engineering and Technology
• /
• v.17 no.4
• /
• pp.66-72
• /
• 2003

This paper proposes an optimum, problematic design for structural and control systems, taking a 3-D truss structure as an example. The structure is subjected to initial static loads and time-varying disturbances. The structure is controlled by a state feedback H$_{\infty}$ controller which suppress the effects of disturbances. The design variables are the cross sectional areas of truss members. The structural objective function is the structural weight. For the control objective, we consider two types of performance indices, The first function represents the effect of the initial loads. The second function is the norm of the feedback gain, These objective functions are in conflict with each other but are transformed into one control objective by the weighting method. The structural objectives is treated as the constraint, By introducing the second control objective which considers the magnitude of the feedback gain, we can create a design to model errors.

• Proceedings of the KIEE Conference
• /
• 1994.07a
• /
• pp.432-434
• /
• 1994

This paper describes a phase-shifter which can flexibly adjust the active and reactive power flow through an ac transmission line. The phase-shifter has two voltage-source converters sharing an energy storage capacitor. The magnitude of the injected voltage is controlled by the converter I connected in parallel with the sending terminal, while that of phase angle by the converter II in series with the line through the coupling transformer. In order to analyze the whole system operation, an equivalent circuit model was developed and verified by a computer simulation with EMTP code.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.10 no.1
• /
• pp.15-26
• /
• 2004

Pharmaceuticals require more detailed packaging than do other sensitive products, such as foods, although there are several similarities in their requirements. Because the required action of a medication can be nullified by any deterioration in its active principles the protection required from its packaging is at least an order of magnitude greater than that needed by foods. Therefore, security and integrity of the package are more important and are controlled by licensing arrangements. To achieve levels of safety, reliability, and quality, pharmaceutical firms must identify and correct potential problems with packaging functions. Purpose of this study is to identify the present issues pharmaceutical packaging and to forecast their future for the development of pharmaceutical packaging.

• Proceedings of the KIPE Conference
• /
• 2008.06a
• /
• pp.69-71
• /
• 2008

Recently, the interest on power quality has been hot issue because the equipments cause voltage disturbance and become more sensitive to the voltage disturbance. The DVR(Dynamic Voltage Restorer) is one of the Custom Power Device that can compensate the voltage. DVR operates as a series connected compensator whose output voltage can be controlled system voltage. And the magnitude of compensation voltage is limited by the characteristics of system and load. Compensation capability of DVR was simulated by EMTDC under several condition. This paper analyzed effect of DVR's compensation at power quality test center which has SSFG(Sag, swell, and Flicker Generator, CPDs(SSTS, DVR, DSTATCOM), and loads.

• Proceedings of the KIEE Conference
• /
• 2006.07d
• /
• pp.1821-1823
• /
• 2006

This paper presents a development of interface device for electro-oculogram(EOG) signal and it's application to the wireless mouse of wearable PC. The interface device is composed of five bio-electrodes for detecting oculomotor motion, several band-pass filters, instrumentation amplifier and a microprocessor. we have first analyzed impedance characteristics between skin and a bio-electrode. since the impedance highly depends on human face, it's magnitude differs from person. this interface device was applied to develop a wireless mouse for wearable PC, as a Bio Machine Interface(BMI). Where in the prompt on PC monitor is controlled by only EOG signals. this system was implemented in a Head Mount Display(HMD) unit. experimental results show the accuracy of above 90%.

• International Journal of Control, Automation, and Systems
• /
• v.3 no.spc2
• /
• pp.346-354
• /
• 2005

This paper presents a new approach to Thyristor Controlled Phase Shifter (TCPS) control. In this paper we have proposed a nonlinear coordinated generator excitation and TCPS controller to enhance the transient stability of a power system. The proposed controller is able to control three main parameters affecting a.c. power transmission: namely excitation voltage, phase angle and reactance in a coordinated manner. The TCPS is located at the midpoint of the transmission line. A nonlinear feedback control law is proposed to linearize and decouple the power system. The design of the proposed controller is based on the local measurements only. Simulation results have been shown to demonstrate the effectiveness of the proposed controller for the enhancement of transient stability of the power system under a large sudden fault.

• Journal of the Korean GEO-environmental Society
• /
• v.15 no.11
• /
• pp.29-42
• /
• 2014

This paper investigates the effects of micro-tunneling on buried pipelines parametrically. A simplified numerical approach was developed and various parametric studies have been conducted to evaluate the effects of ground settlements on the response of buried pipelines. The controlled parameters included the pipe stiffness, ground loss magnitude, and pipe location with respect to a micro-tunnel. Maximum settlement and curvature along a pipeline have been investigated and compared among others for different conditions. In addition, the numerical results have been compared with a theoretical method by Attewell et al. (1986), which is based on a Winkler type linear-elastic solution. The comparison indicated that the response of buried pipes to micro-tunneling-induced ground settlements highly depends on the soil-pipe interaction including the separation and slippage of pipe from soil with the effects of the investigated parameters. Therefore, rather than using the theoretical method directly, it would be a better assessment of the response of buried pipelines to consider the soil-pipe interaction in more realistic conditions.

• Journal of the korean society of oceanography
• /
• v.34 no.4
• /
• pp.231-235
• /
• 1999

A simple analytic model for estimating the volume transport of the Tsushima Current is considered by assuming that the transports through the connecting channels, the Korea and Tsugaru Straits, are geostrophically controled. The model gives a much simpler form of solution than that by Minato and Kimura (1980). It depends no longer on the geometry of the marginal sea and on the thickness of western boundary layer relative to the dimension of the ocean, but considers the geometry of the connecting channels ignored by Nof (1993). The external parameters turn out to be the oceanic meridional sea level difference between the two channels, the depth of the channels and the meridional position of the marginal sea. For typical value of the depth ratio of the channels to the ocean, the model gives an estimate of the Tsushima Current transport of acceptable magnitude.

• Journal of the Semiconductor & Display Technology
• /
• v.14 no.2
• /
• pp.41-45
• /
• 2015

From 20nm technology node, the finFET has become standard device for ULSI's. However, the finFET process made stacking gate non-volatile memory obsolete. Some reported capacitor-less DRAM structure by utilizing the FBE. We present possible non-volatile memory device structure similar to the dual gate MOSFET. One of the gates is left floating. Since body of the finFET is only 40nm thick, control gate bias can make electron tunneling through the floating gate oxide which sits across the body. For programming, gate is biased to accumulation mode with few volts. Simulation results show that the programming electron current flows at the interface between floating gate oxide and the body. It also shows that the magnitude of the programming current can be easily controlled by the drain voltage. Injected electrons at the floating gate act similar to the body bias which changes the threshold voltage of the device.

• Journal of Electrical Engineering and Technology
• /
• v.6 no.3
• /
• pp.334-341
• /
• 2011

This paper presents accurate solutions for nonlinear transcendental equations of the selective harmonic elimination technique used in three-phase PWM inverters feeding the induction motor by particle swarm optimization (PSO). With the proposed approach, the required switching angles are computed efficiently to eliminate low order harmonics up to the $23^{rd}$ from the inverter voltage waveform, whereas the magnitude of the fundamental component is controlled to the desired value. A set of solutions and the evaluation of the proposed method are presented. The obtained results prove that the algorithm converges to a precise solution after several iterations. The salient contribution of the paper is the application of the particle swarm algorithm to attenuate successfully any undesired loworder harmonics from the inverter output voltage. The current paper demonstrates that the PSO is a promising approach to control the operation of a three-phase voltage source inverter with a selective harmonic elimination strategy to be applied in induction motor drives.