• The Korean Journal of Ecology
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• v.17 no.2
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• pp.105-112
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• 1994

Structure of grassland communities was investigated, and performance of populations of Themeda triandra var. japonica and Miscanthus sinensis were compared on limestone and granite soils. Forty three and forty taxa occurred on the limestone and granite grasslands, respectively, but their similarity was very low. Shoot height and number of hills per patch, as a measure of performance, of Themeda on the limestone grassland were higherthan those on the granite grassland. In contrast, shoot height and number on hills per patch of Miscanthus were higher on limestone than granite grassland. Evidence shows that poor growth of Micanthus population on the limestone soil was associated with higher content of insoluble divalent cations than soluble ones in shoot tissue.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2019.11a
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• pp.206-207
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• 2019

MPEG 에서는 최대 6 자유도(6DoF)를 가지는 몰입형 미디어의 압축 표준화를 진행하고 있다. 360 비디오에 움직임 시차(parallax)를 추가한 것으로 정의되는 3DoF+의 가상 공간에서, 원하는 위치의 장면을 제공하려면 다른 위치에서 찍은 여러 비디오를 사용하여 임의의 원하는 시점의 뷰(view)를 렌더링 해야 한다. MPEG-I Visual 그룹에서는 이러한 3DoF+ 비디오의 효율적인 부호화 및 전송을 위한 표준화가 진행되고 있으며, 최근 시험모델(TMIV)을 개발하고 있다. 본 논문은 TMIV 에서 패치(patch)를 아틀라스(atlas)에 효율적으로 패킹하여 부호화 성능을 향상시킬 수 있는 패치 패킹 방법을 제안한다. 제안 방식은 패킹되는 패치들 간에 보호 대역(Guard Band)를 적용하여 패치간의 거리를 둠으로써 부호화로 인해 발생할 수 있는 아티팩트(artifact)를 줄여 최종 복원 뷰의 화질을 향상시킨다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.566-568
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• 2008

An E-OPMT(Electronically-controllable OPMT) was developed as an alternative of OPMT which could adjust the direction of the generated guided waves in a plate manually. The key idea of controlling the wave direction electronically is based on a few sets of axisymmetric figure-of-eight coils and the magnet which is located for making static omni-directionally biasing magnetic field over the patch. However, in order to explain wave phenomenon generated by this transducer, a new approach is required because there are various combinations between static biasing magnetic field and dynamic actuating magnetic field on the patch, not similar to OPMT. In this paper, the experiments were performed to understand characteristics of E-OPMT and the new theoretical analysis was set up for explaining the result.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.20 no.3
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• pp.268-275
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• 2007

Objectives : Pityriasis rosea is a rash that occurs most commonly in people between the ages of 10 and 43, but may occur at any age. It is common disease but I was haven't meet any case by oriental medical treatment. Methods : We experienced one case of Pityriasis rosea treated with oriental medical treatment, acupuncture and herbal medication. Results : The patient suffer from a large, scaly, pink patch on the chest and back and arm and leg. He have very terrible itching sign. After treatment his itching was subsided and large, scaly, pink patch was disappear. Conclusions: Oriental medical treatment could be safe and effective method in pityriasis rasea

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.11
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• pp.1177-1183
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• 2009

The effects of biasing magnetic fields on the performances of magnetostrictive ultrasonic transducers are investigated. The transducers are patch-type ones which are used for SHM of plate structures. Various kinds of configurations of biasing magnets are covered experimentally. It is experimentally verified that how the biasing magnetic field deploys is the most significant factors on maximizing the transducer output. From the magnetostriction curve of nickel, it is concluded qualitatively that it is not the absolute values of biasing magnetic field but the slope of magnetostriction curve to be taken account of.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2003.11a
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• pp.230-233
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• 2003

In this paper, the wideband microstrip patch antennas for the Personal communications Service $(PCS\;:\;1750\~1870\;MHz)$ and International Mobile Telecommunications-2000 $(IMT-2000\;:\;1920\~2170\;MHz)$ dual band are studied. Experimental and simulation results on the dual band antenna are presented. Simulation results are in good agreement with measurements. The experimental and simulation results confirm the wideband characteristics of the antenna. The studied antenna satisfied the wideband characteristics that are required characteristics for above 420 MHz impedance bandwidth for the PCS and IMT-2000 dual band antenna. In this paper, through the designing of a dual band antenna, we have presented the availability for PCS & IMT-2000 base station antenna. An impedance bandwidth of $31\%(VSWR<1.5,\;615\;MHz)$ and a maximum gain of 7dBi can be achieved. The radiation pattern is stable across the passband.

• Journal of Chest Surgery
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• v.24 no.7
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• pp.719-724
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• 1991

A case of pulmonary atresia with intact ventricular septum was presented in a 10-month-old cyanotic female patient, which was congenitally rare. Infant with pulmonary atresia and intact ventricular septum usually require urgent surgical intervention. Angiogram showed the pulmonary atresia at the level of the pulmonary valve, the hypoplasia of tricuspid valve and atrial septal defect without patent ductus arteriosus. We performed the pericardial patch graft on the right ventricular outflow tract and pulmonary artery after ventriculotomy using pacemaker wire as electrical saw and main pulmonary arteriotomy and then modified Waterston shunt from the ascending aorta to patch on the right ventricular outflow tract without extracorporeal circulation. Patient was postoperatively good condition.

• Geophysics and Geophysical Exploration
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• v.15 no.4
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• pp.245-248
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• 2012

Two dimensional Fourier transform can be used for the upward continuation of gravity or magnetic field data acquired at given altitude over a rectangular area. Earth's curvature is often neglected in most potential field continuations, however, it should be considered over several hundred kilometer field area. In this study, we developed a new method retaining terms of Earth's curvature to better perform the continuation of potential field on spherical patch area.

• Journal of electromagnetic engineering and science
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• v.13 no.4
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• pp.240-244
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• 2013

In this paper, we present an improvement of a closed-form formula for mutual impedance computation. Depending on the center-to-center spacing between two rectangular microstrip patch antennas, the mutual impedance formula is separated into two parts. The formula based on synthetic asymptote and variable separation is utilized for spacings of more than 0.5 ${\lambda}_0$. When the spacing is less than 0.5 ${\lambda}_0$, an approximate formula is proposed to improve the computation for closely spaced elements. Simulation results are compared to computational results of mutual impedances and mutual coupling coefficients as functions of normalized center-to-center spacing in both E- and H-plane coupling configurations. A good agreement between simulation and computation is achieved.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1993-1995
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• 2003

In this paper, a Dolph-Tschebyscheff type Microstrip array patch Antenna was designed and simulated with a commercial tools. Then we fabricated an Antenna and took a measurement of the radiation pattern of the Antenna in the Anechoic Chamber room. Despite of the same case, each simulation using commercial tools showed some different results. The simulation using the Microwave Studio gave more desirable result than the ADS. We found the error of the progress of production.