• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2000년도 추계종합학술대회 논문집(2)
• /
• pp.313-316
• /
• 2000

Concentric-Circle-Grating (CCG) cavity is analyzed by coupled mode theory. In this case concentric grating is acting as both feedback element and output coupler. In our calculations radiation loss terms are included in guided coupled mode equations. The surface-emitted field distribution is obtained in self-consistent manner.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
• /
• pp.13-14
• /
• 2003

Burgess?s concentric zone model is a famous theory in the geography of city. However, the zone border line drawing method was uncertain. We have developed the method of drawing the border using land use images.

• 한국연소학회지
• /
• 제4권2호
• /
• pp.75-83
• /
• 1999

The effect of temperature distributions on soot volume fraction in double-concentric diffusion flames have been investigated experimentally. Using fine thermocouple wires and a rapid insertion mechanism, we have measured temperature without the effect of soot particles attached to the thermocouple junction, which can lower the temperature signal about 100 K by increasing the heat loss from the junction by radiation. The temperature at the flame axis is higher in the double-concentric diffusion flames than in normal co-flow diffusion flames because of the inverse diffusion flame. However, it is almost the same as that at the periphery of normal flames, on which the inverse flame does not have an effect. Thus, the lower soot concentration found in the double-concentric diffusion flame can be explained by the effect of nitrogen diffusion from the central air jet.

• The Journal of Korean Physical Therapy
• /
• 제14권4호
• /
• pp.260-265
• /
• 2002

There are many methods for muscle strengthening. Muscle strengthening with eccentric contraction work is the best way by researcher's report. Also, eccentric contraction need proper resistance for muscle strengthening. Combination of isotonic in PNF is a muscle strengthening method with manual resistance. It makes concentric contraction $\rightarrow$ eccentric contraction $\rightarrow$ concentric contraction with continually and without muscle relaxation. Combination isotonic technique use with PNF pattern. Therefore, it will make development and increasing of active control motion, coordination, actual range of motion, strengthen and functional training in eccentric control of movement. Concentric contraction have the 3rd lever system and eccentric contraction have the 2nd lever system with combination of isotonic. Serial concentric contraction $\rightarrow$ eccentric contraction $\rightarrow$ concentric contraction make strong SEC and PEC. It will be increase elasticity of SEC, PEC and contractile components either.

• 전기학회논문지
• /
• 제62권2호
• /
• pp.239-245
• /
• 2013

In this paper, we propose a time-frequency domain reflectometry (TFDR) based measurement method for localizing concentric neutrals corrosion on live underground power cable. It consists of two inductive couplers which can transmit the reference signal into live underground power cable and measure the reflected signals from the impedance discontinuities of concentric neutrals corrosion. In order to compensate the dispersion of the measured reflected signal via inductive coupler, an equalizer based on Wiener filtering is designed. To improve the localizing performance of concentric neutrals corrosion in the vicinity of the measurement point, the reference signal is removed from the measured reflected signals. The localization performance of the proposed method is verified by the concentric neutrals corrosion localization experiment.

• The Journal of Korean Physical Therapy
• /
• 제35권2호
• /
• pp.43-47
• /
• 2023

Purpose: This study compared the movement control ability of the ankle joint according to the type of muscle contraction, namely, eccentric or concentric contractions. Methods: Thirty-four healthy adult subjects participated in this study. As a single group, before the experiment, the subjects were trained on achieving the required position of the ankle around the target point by manually controlling the ankle dorsiflexion by 10°. Concentric contraction starts at 0° and continues until the target point of 10° is reached. During an eccentric contraction, the ankle joint starts at 20° ankle dorsiflexion and continues till the target point is reached. Movements using eccentric contraction and concentric contraction were randomly performed 3 times each. Results: The results of comparing the difference in the movement control ability of each type of muscle contraction of ankle dorsiflexion showed that the measurement-remeasurement error was significant in eccentric contraction. Conclusion: In this study, we found a difference in the ability to control movement according to whether the contraction is eccentric or concentric. Therefore, we propose that the ability to control movement is affected by the type of muscle contraction.

• 방송공학회논문지
• /
• 제11권2호
• /
• pp.164-173
• /
• 2006

동심원 모자이크 데이터 구조는 천천히 움직이는 카메라를 통해 얻는 비디오 시퀸스의 구조와 유사하다. 동심원 모자이크는 이러한 구조의 데이터들을 정렬하거나 합쳐서 모자이크 영상을 얻게 된다. 따라서 동심원 모자이크는 엄청나게 많은 양의 데이터를 필요로 하기 때문에 압축은 필수적이다. 따라서 압축 데이터를 그대로 유지하면서 특정 장면을 복호화 할 수 있는 알고리즘이 필요하다. 본 논문에서는 동심원 모자이크의 압축을 위하여 3차원 리프팅 변환을 사용하였다. 리프팅 변환은 웨이브렛의 장점을 그대로 유지하면서 연산량과 메모리의 사용량을 줄일 수 있다. 3차원으로 변환된 압축 비트 스트림은 프레임들 사이에 복잡한 연관성을 갖게 되어 특정 장면의 검출에 대한 복잡도가 높아지게 된다. 따라서 비교적 우수한 압축 성능을 가지면서 특정 장면의 검출에 대한 복잡도를 낮추기 위해 3차원 변환된 데이터를 프레임 단위로 압축하였다 압축은 가변적인 비트율을 사용하여 압축된다. 또한 리프팅 구조의 특징을 사용하여 압축 데이터의 형태를 유지하면서 특정한 장면을 복호화 할 수 있는 알고리즘을 제안하였다.

• 한국인터넷방송통신학회논문지
• /
• 제10권1호
• /
• pp.91-96
• /
• 2010

동심원 모자이크는 공통의 공간적인 기준을 사용하여 비디오 분할의 프레임들을 정렬시키거나 합쳐서 형성된다. 과거의 3차원 웨이브렛 변환 코딩의 연구와 비교하여 유연한 부분적 부호화와 비트 스트림의 임의 검색을 가능하게 하여주는 중요한 구성을 고려하여 압축된 동심 모자이크의 just-in-tim(JIT) 표현 알고리즘을 제안하였다. 이 동심 모자이크의 JIT 표현이 실시간 표현을 수행하기 위해서는 많은 계산량이 요구된다. 압축된 형태로 데이터가 유지되어 특정 장면을 표현하기 위해 사용되는 내용만이 복호 되어야 한다. 그래서 제안된 알고리즘은 웨이브렛을 리프팅 계산식의 구조를 사용하여 동심 모자이크의 실시간 표현을 가능하게 해준다.

• The Journal of Korean Physical Therapy
• /
• 제16권4호
• /
• pp.1-10
• /
• 2004

The purpose of this study was to investigate the effects of treadmill aerobic exercise training on isokinetic muscle strength in students with cerebral palsy. The subjects consisted of 9 female students with cerebral palsy between the ages of 10 to 22. The subjects performed treadmill aerobic exercise training with $0\%$ grade by free speed with three times a week for 20 minutes a session and 12 weeks. Concentric peak torque of knee flexors and knee extensors was measured before training and after training at $30^{\circ}/sec$ and $60^{\circ}/sec$ by isokinetic dynamometer. Paired t-test was used to assess changes in variables of isokinetic muscle strength. The results of analysis are as followings. 1) After training, concentric peak torque of the least affected knee flexors(p<.01) and the most affected knee flexors (p<.01) and concentric peak torque of the least affected knee extensors(p<.01) and the most affected knee extensors(p<.01) at $30^{\circ}/sec$ significantly increased. 2) After training, concentric peak torque of the least affected knee flexors(p<.05) and the most affected knee flexors(p<.01) and concentric peak torque of the least affected knee extensors(p<.05) and the most affected knee extensors(p<.01) at $60^{\circ}/sec$ significantly increased. These findings provide evidence that treadmill aerobic exercise training improves isokinetic muscle strength in students with cerebral palsy.

• 전자공학회논문지B
• /
• 제32B권11호
• /
• pp.1393-1404
• /
• 1995

For the factory automation(FA) of production or assembly lines, computer vision techniques have been widely used for the recognition and position-control of objects. In this application, it is very important to analyze characteristic features of each object and to find an efficient matching algorithm using the selected features. If the object has regular or homogeneous patterns, the problem is relatively simple. However, If the object is shifted or rotated, and if the depth of the input visual system is not fixed, the problem becomes very complicated. Also, in order to understand and recognize objects with concentric noise patterns, it is more effective to use feature-information represented in polar coordinates than in cartesian coordinates. In this paper, an algorithm for the recognition of objects with concentric circular noise-patterns is proposed. And position-conrtol information is calculated with the matching result. First, a filtering algorithm for eliminating concentric noise patterns is proposed to obtain concentric-feature patterns. Then a shift, rotation and scale invariant alogrithm is proposed for the recognition and position-control of objects uusing invariant feature information. Experimental results indicate the effectiveness of the proposed alogrithm.