• 융합신호처리학회 학술대회논문집
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• 한국신호처리시스템학회 2000년도 추계종합학술대회논문집
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• pp.113-116
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• 2000

본 논문에서는 카메라 또는 카메라 플랫폼의 흔들림 등의 외부 영향과 비디오 시퀸스내의 모션이 함께 있을 경우의 출렁이는 비디오를 전자적으로 안정화시키는 방법을 제안한다. 일반적인 영상 안정 시스템은 모션 측정과 모션 보상의 두과정으로 구성되어 있다. 모션 측정에서 프레임간 모션 모델을 가정하고 모션 파라메타를 측정한다. 모션 보상에서는 측정된 파라메타를 이용하여 현재 영상 좌표계를 기준 영상 좌표계로 변환하고 명암값 보간을 하여 영상안정을 이루어 낸다. 그러나 상기의 방법으로는 카메라 움직임외에 다른 모션 요소가 있을 때 어려움을 겪게 된다 이의 해결을 위해 motion vector scatter diagram(MVSD)에 기반한 지배 모션 측정 방법을 제안한다 이 방법은 영상을 일정영역의 subblock으로 나눈후 각 subblock의 중심을 특징점으로 잡아 correlation 과정을 거쳐 영상간의 모션 벡터를 구한 다음 구해진 모션 벡터로 needle diagram과 MVSD를 구축한다. 구축한 MVSD의 패턴은 모션의 종류에 따라 일정한 모양을 갖게 되는데 이의 분석을 위해 목적함수를 정의하고 피 함수의 최적화를 통해 지배 모션 파라메타를 측정한 후 그 파라메타로 모션 보상을 함으로서 영상안정을 이룰 수 있다.

• 전기학회논문지
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• 제65권2호
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• pp.319-328
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• 2016

This paper proposes a simplified SVPWM for three level inverters in transformerless photovoltaic (PV) systems. With the proposed SVPWM the three level space vector (SV) diagram is divided into only six sectors as in conventional two level SV diagram in such a way that only seven SVs are used among all the available SVs of three level inverter. The main features of the proposed SVPWM are that it is simple to implement, less switching losses as compared to conventional SVPWM and most importantly it eliminates the leakage currents in transformerless PV systems. Detailed theoretical analysis of the proposed SVPWM are presented and verified by numerical simulations and experimental results.

• 전기학회논문지
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• 제56권6호
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• pp.1071-1079
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• 2007

In this paper, a novel space vector control method for isolated multi-level inverter using 3-phase low frequency transformers is proposed. This method is based on the simplification of the space-vector diagram of a five-level inverter using calculated table into fully programming method. The execution time of the proposed method is about same as that of the method using calculated table. Also, the proposed method is easily applied to other case level inverter. We applied this method into the 3-phase IHCML inverter using common arm. It makes possible to use a single DC power source due to employing low frequency transformers. In this inverter, the number of transformers could be reduced compare with an exiting 3-phase multi-level inverter using single phase transformer. In addition, this method generates very low harmonic distortion operation with nearly fundamental switching frequency. Finally, We tested multi-level inverter to clarify electric circuit and reasonableness through Matlab simulation and experiment by using prototype inverter.

• 한국자동차공학회논문집
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• 제5권4호
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• pp.171-178
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• 1997

Vehicle interior noise has become increasingly important in this recent years. The noise of a vehicle is one of the important problems in a vehicle design. The interior noise is caused by various vibration sources of vehicle compartment. The booming noise of a vehicle can be significantly affected by vibrations transmitted from engine excitation forces to the vehicle body. Specially, we are interested in the state of transmission paths such as engine mounts to reduce noise in a vehicle compartment. In this paper, we have been calculated the contribution of each transmission path such as engine mounts to interior noise. To identify contribution of each input sources and transmission paths to output, the effectiveness of each input component to output is calculated. Sensitivity analysis is carried out for investigation of contribution to output due to input variations. With the simulation of magnitude and phase change of inputs using vector synthesis diagram, the trends of synthesized output vector are obtained. As a result, we suggested sensitivity analysis of vector synthesis as a technique of prediction and control for noise in a vehicle compartment.

• 한국소음진동공학회논문집
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• 제17권12호
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• pp.1254-1261
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• 2007

The structure has several types of noise and booming noise of a vehicle is usually caused by the vibration of the vehicle's body transmitted from the engine through the mounting system. Vector synthesis analysis is performed to predict the booming noise when the characteristic of the engine mounting system is changed., i.e., when magnitudes and phases of vibratory forces after the mounts are altered. To use this method effectively, the concept of Multi-dimensional-analysis and Experimental Design are introduced to identify the contributions of each vibration sources and transmission paths to interior noise. It was used 3inputs/1output system and found the magnitudes and phases of the forces for minimizing the noise. Finally, the synthesized interior booming noise level is predicted by the vector synthesis diagram. It is shown that the vector synthesis method can be used to obtain the optimum design characteristic of the mounting system to control the interior booming noise of a vehicle.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 추계학술대회논문집
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• pp.495-499
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• 2000

The booming noise of a vehicle is usually caused by the vibration of the vehicle's body transmitted from the engine through the mounting system. Thus the engine mounting system must be cautiously designed to reduce the noise. Vector synthesis analysis is performed to predict the booming noise when the characteristic of the engine mounting system is changed., i.e., when magnitudes and phases of vibratory forces after the mounts are altered. To effectively use the method, the concept of 'effectiveness' is introduced to identify the contributions of each vibration sources and transmission paths to interior noise. When the magnitudes and phases of the forces due to the engine vibration are changed, the synthesized interior booming noise level is predicted by the vector synthesis diagram. Thus, the optimum characteristics of the forces are obtained through the simulations of the vector synthesis analysis. It is shown that the vector synthesis method can be used to obtain the optimum design characteristic of the mounting system to control the interior booming noise of a vehicle.

• Journal of Multimedia Information System
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• 제7권2호
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• pp.165-174
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• 2020

This document outlines a new color image encryption technology development. After splitting the original image into 240-bit blocks and modifying the first block by an initialization vector, an improved Feistel circuit is applied, sponsored by a genetic crossover operator and then strong chaining between the encrypted block and the next clear block is attached to set up the confusion-diffusion and heighten the avalanche effect, which protects the system from any known attack. Simulations carried out on a large database of color images of different sizes and formats prove the robustness of such a system.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2001년도 춘계종합학술대회
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• pp.688-691
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• 2001

By using basic paths in the 0-tree of a linear TPMACA C we obtain the state-transition diagram of complemented CA C'derived from C such that the complement vector is a nonzero attractor of C. Also we analyze the behavior of C'.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부A
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• pp.176-178
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• 1998

Recently, Control method of induction Motor is applied in full circuit model, as circular diagram. In Elevetor moderization problem, there is no circuit information. Nothing but, Motor terminal voltage and HP of motor. So, in this study, using KS induction Motor table, try to solve initial valve problem and make some implementations of manual tuning for use of automatic tuning of induction motor parameter.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2003년도 추계학술대회 논문집
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• pp.11-16
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• 2003

The 3-level converter/inverter system is very efficient in the ac motor drives of high voltage and high power application. This paper proposed a simple method to diagnose faults using change of current vector pattern in space vector diagram when the faults occurrence in the 3-level inverter and a control method that can protect system from unbalance of the neutral point voltage according to faults. The validity of the proposed method is demonstrated by the simulation results.