• New & Renewable Energy
• /
• v.1 no.2 s.2
• /
• pp.11-18
• /
• 2005

A modular photovoltaic PCS with high-frequency isolation is proposed. The proposed system consists of a SEPIC converter and a full-bridge inverter Using the power slope versus voltage of the PV array, the MPPT controller is proposed that produces a smooth transition to the maximum power point. The dc current of the PV array is estimated without using a dc current sensor The disturbance of the line voltage is detected using a fast sensing technique. Experimental results obtained on a 500W prototype show high performance such as almost unity power factor, $90\%$ power efficiency, $3.6\%$ THD.

• Journal of the Korean Society of Safety
• /
• v.17 no.2
• /
• pp.32-38
• /
• 2002

In this paper, a new approach for the SynRM(Synchronous Reluctance Motor) control which ensures producing MTPA(Maximum Torque per Ampere) over the entire field weakening region is presented. In addition, this paper presents a speed sensorless control scheme of SynRM using flux observer. Also, by adjusting the base speed for the field weakening operation according to the flux level, the current and voltage limit, the smooth and precise transition into the field weakening operation can be achieved. The validity of the proposed scheme is verified through simulation.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2007.05a
• /
• pp.311-315
• /
• 2007

In this paper, a new approach for the Synchronous Reluctance Motor control which ensures producing Maximum Torque per Ampere(MTPA) over the entire field weakening region is presented. In addition, This paper presents a speed sensorless control scheme of SynRM using artificial neural network. Also, by adjusting the base speed for the field weakening operation according to the flux level, the current and voltage limit, the smooth and precise transition into the field weakening operation can be achieved The proposed scheme is verified validity through simulation.

• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.43 no.2
• /
• pp.225-232
• /
• 1994

In this paper, a new approach for the induction machine control whih ensures producing maximum torque per ampere over the entire field weakening region is presented. In addition, the relation of the output torque capability with the leakage factor of the machine is examined. Also the smooth and precise transition into the field weakening operation can be achieved by adjusting the base speed for the field weakening operation according to the flux level, the current limit and the voltage limit. The proposed is verified through simulation and experiment for a 5hp laboratory induction motor drive system.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.54 no.4
• /
• pp.185-191
• /
• 2005

In this paper, a new approach for the Synchronous Reluctance Motor control which ensures producing Maximum Torque per Ampere(MTPA) over the entire field weakening region is presented. In addition, This paper presents a speed sensorless control scheme of SynRM using artificial neural network. Also, by adjusting the base speed for the field weakening operation according to the flux level, the current and voltage limit, the smooth and precise transition into the field weakening operation can be achieved. The proposed scheme is verified validity through simulation.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.43 no.8 s.350
• /
• pp.69-76
• /
• 2006

In this paper, we propose blind adaptation strategies for decision feedback equalizer (DFE) optimizing the operation mode between acquisitionand tracking modes based on adjustable soft decision devices. The proposed schemes select an optimal soft decision device to generate feedback samples for the DFE at a given noise to signal ratio, and apply corresponding adaptation rules which combine a blind infinite impulse response (IIR) filtering adaptation and the decision-directed least mean squared (DD-LMS) DFE adaptation. These adaptation approaches attempt to achieve not only smooth transition between acquisition and tracking of DFE but also mitigation of error propagation.

• Clinical and Experimental Pediatrics
• /
• v.57 no.6
• /
• pp.257-263
• /
• 2014

The incidence of people living with congenital heart disease (CHD) has been increasing every year owing to remarkable advances in surgical and catheter intervention techniques and devices, and improved knowledge of critical care for patients with CHD. However, these patients continue to face physical, psychosocial, and environmental challenges, and a number of studies have shown higher rates of depression and anxiety disorders than the general population. To improve psychosocial functioning and quality of life for adults with CHD, health care providers are recommended to inform CHD patients of an accurate diagnosis, and overall treatment process, beginning in adolescence to facilitate a smooth transition from adolescence to adulthood. Active cooperation with psychiatrists, psychologists, social workers, chaplains, and family members is highly recommended to help CHD patients feel normal and optimistic and to promote good social interactions, close family relationships, and a strong sense of coherence.

• International Journal of CAD/CAM
• /
• v.12 no.1
• /
• pp.38-47
• /
• 2012

The paper proposes a method for generating a sequence of images with smooth transition of illumination from two input images with different lighting conditions. Our relighting approach is image-based, such as the light field rendering. We store the luminances (pixel RGB values) into "lighting functions" consisting of a couple of parameters related to normal vectors. Images with different light positions are rendered by interpolating the luminances retrieved from the lighting functions. The proposed method is a promising technique for many applications requiring a scene with variety of lighting effects, such as movies, TV games, and so on.

• Journal of Computational Design and Engineering
• /
• v.2 no.4
• /
• pp.197-205
• /
• 2015

Bladed disk (BLISK) is a vital part in jet engines with a complicated shape which is exclusively machined on a five-axis machine and requires high accuracy of machining. Poor quality of tool orientation (e.g., false tool positioning and unsmooth tool orientation transition) during the five-axis machining may cause collision and machine vibration, which will debase the machining quality and in the worst case sabotage the BLISK. This paper presents a reference plane based algorithm to generate a set of smoothly aligned tool orientations along a tool path. The proposed method guarantees that no collision would occur anywhere along the tool path, and the overall smoothness is globally optimized. A preliminary simulation verification of the proposed algorithm is conducted on a BLISK model and the tool orientation generated is found to be stable, smooth, and well-formed.

• Bulletin of the Korean Chemical Society
• /
• v.35 no.7
• /
• pp.2093-2096
• /
• 2014

2H-azirine, a less known acetonitrile isomer, is observed in matrix IR spectra from the precursor exposed to radiation from laser ablation of transition-metals. Its vibrational characteristics confirm the previous results, and those for the deuterated and $^{13}C$ substituted isotopomers are also newly reported. The weak absorptions are traced to the low production yield due to its high energy and low extinction constants. IRC computations reveal smooth inter-conversion between 2H-azirine and $CH_2NCH$, providing a rationale for the observed variation of their relative contents during photolysis.