• ETRI Journal
• /
• v.29 no.6
• /
• pp.811-813
• /
• 2007

We report on a ridge waveguide laser diode with laterally tapered waveguides fabricated in a single growing step using a double patterning method. In this structure, nearly constant output power is obtained with the change of the lower tapered waveguide width, and the facet power ratio of 1.4 to 1.5 is observed over the current range. The asymmetric facet power property is also investigated.

• Journal of the Korean Institute of Telematics and Electronics A
• /
• v.32A no.10
• /
• pp.25-34
• /
• 1995

A new vertical power MOSFET with over-current protection capability is proposed. The MOSFET consists of main power MOSFET cell, sensing MOSFET cell and lateral npn bipolar transistor. The proposed MOSFET may be fabricated by a conventional DMOS process without any additional fabrication step. Overcurrent state is sensed by the newly designed lateral bipolar transistor. Mixed-mode simulations proved that the overcurrent protection is achieved by the proposed MOSFET successfully with a small protection area less than 0.2 % of the total die area.

• Proceedings of the KIPE Conference
• /
• 1999.07a
• /
• pp.675-679
• /
• 1999

A single-phase PWM current source rectifier with a neutral leg is presented and throughly analyzed in this paper. This novel topology is implemented by adding an extra leg a step-down single phase PWM space vector modulation method to reduce the dc output voltage harmonics is proposed. The PWM pattern generation need a digital system. As compared with a conventional single-phase PWM rectifier, over 20% improvement of the total harmonics distortion in the output voltage can be obtained. Different SVM techniques are analyzed for this PWM rectifier and simulation result are presented.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.25 no.1
• /
• pp.63-71
• /
• 1988

In this paper, a fast matching method using hierarchical neighborhood search and subtemplate to reduce very heavy computational load of the conventional matching method, is presented. Some parameters of the proposed method are chosen so that an automatic target tracker to which it is applied can track one moving object well in comparatively simple background. Experimental results show that its performance is not so degraded in spite of high computational reduction over that of the matching method using 3-step search.

• Journal of applied mathematics & informatics
• /
• v.30 no.1_2
• /
• pp.127-133
• /
• 2012

We establish the polynomial convergence of a new class of path-following methods for SDLCP whose search directions belong to the class of directions introduced by Monteiro [3]. We show that the polynomial iteration-complexity bounds of the well known algorithms for linear programming, namely the short-step path-following algorithm of Kojima et al. and Monteiro and Alder, carry over to the context of SDLCP.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.24 no.4
• /
• pp.684-695
• /
• 1987

In this paper, an improved matching method using subtemplate of moving region and 3-step search algorithm is proposed. It reduces heavy computational load of the conventional method and also can continuously track the target even with occlusion. The proposed method is applied to an automatic target tracker using high speed 16bit microprocessor in order to track one moving target in real time. Experimental results show that the proposed method has better performance over the conventional method in spite of greately reducing the computational load, even in case with complex background and/or with occlusion.

• Korean Architects
• /
• v.3 no.9 s.9
• /
• pp.44-51
• /
• 1968

This article discusses at a basic level the of chimney construction. The concept, design, and operation can be understood easily. This, of course, is the first step to orderly construction. The selection of the boiler as to type, capacity, etc., was summarized in brief. The over all planning of the boiler and chimney together was the main object of this article. The architectural books covering this subject are very technical and this article tries to make the understanding of the basic principles more easy for the beginner in architecture.

• Proceedings of the IEEK Conference
• /
• 2006.06a
• /
• pp.143-144
• /
• 2006

This paper presents an adaptive OFDM system with multistep predictor to effectively compensate multiple feedback delays. The proposed scheme adaptively changes the modulation order per subcarrier based on the predicted CSI to improve data capacity and system performance.

• Journal of the Korean Ceramic Society
• /
• v.18 no.3
• /
• pp.152-156
• /
• 1981

$Fe_2O_3$ was reduced over the temperature range of 600-100$0^{\circ}C$ in both the atmospheres for the Fe-stable and FeO-stable states. It was found that the reduction follows first order kinetics and the reduction of $Fe_3O_3$ to $Fe_3O_4$ is the rate-controlling step.

• Korean Architects
• /
• v.3 no.8 s.8
• /
• pp.27-32
• /
• 1968

This article discusses at a basic level the process of chimney construction. The concept, design, and operation can be understood easily. This, of course, is the first step to orderly construction. The selection of the boiler as to type, capacity, etc. was summarized in brief. The over all planning of the boiler and chimney together was the main object of this article. The architectural books covering this subject are very technical and this article tries to make the understanding of the basic principles more easy for the beginner in architecture.