• Proceedings of the KIPE Conference
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• 1998.07a
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• pp.129-133
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• 1998

This paper deals with a characteristic of output for high frequency resonant inverter type x-ray generator in short exposure time. In the same tube-voltage, the waveform is stable in long exposure time (200msec) but more decreasing exposure time (50msec), the waveform is distorted. The ripple factor of tube-voltage waveform distorted more and more increase tube-voltage and in this case output is also unstable. High-frequency resonant inverter type X-ray generator using PSU source which introduced in resent is stable tube-voltage waveform and low ripple factor.

• The Korean Journal of Applied Statistics
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• v.25 no.5
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• pp.733-741
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• 2012

The successful launch of Arirang satellites allow the acquisition of high resolution satellite imagery of Korean territory and enables the transition from the conventional cultivation area survey method to new image based methods adopted in advanced nations. In this study, we suggested reasonable sizes of the primary sampling unit and the secondary sampling unit for the satellite imagery based sampling design in 8 provinces preselected for this research. The PSU size was determined mainly in consideration of intracorrelation that shows the degree of homogeneity within each cluster and the efficiency of the image process. For the SSU size, we considered the relative standard error and the differences between the land cover maps produced by the Ministry of Environment and the satellite imagery processed by the National Statistical Office.

• Journal of the korean society of oceanography
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• v.35 no.4
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• pp.192-199
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• 2000

Standard CTD data processing recommended by Sea-Bird Electronics produced thermal-lag corrections larger than 0.1 psu for the data taken during the CREAMS expeditions in the northern part of the East/Japan Sea where a vertical temperature gradient frequently exceeds 1.0$^{\circ}$C/m in the upper 100 m near the sea surface. As the standard processing is based upon a recursive filter which was introduced by Lueck and Pickle (1990), coefficients of the recursive filter have been newly derived for the CREAMS data by minimizing the difference between salinities of downcast and upcast in temperature-salinity domain. The new coefficients are validated by comparison with salinities measured by a salinometer, AUTOSAL 8400B. An accurate correction for the thermal-lag is critical in identifying water masses at intermediate depth in the East/japan Sea.

• Ocean and Polar Research
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• v.23 no.1
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• pp.1-10
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• 2001

Sea surface temperature derived from infrared images of NOAA satellites showed a warm eddy in the East Korean Bight(EKB) or Donghan Man during the winter 1997${\sim}$2000. To describe the warm eddy in the EKB, hydrographic data collected in 1934 and 1936 were also analyzed. The center of the warm eddy was located at about $39^{\circ}N$ and $129^{\circ}E$. The temperature and salinity of the eddy was about $4.0^{\circ}C$ and 34.0 psu, respectively, at 100m depth. The eddy rotated anticyclonically with a geostrophic current speed of about 20 cm/s. The mean state calculated from the data of 1922${\sim}$1960 showed the existence of a warm eddy over the EKB in winter. The eddy persists until late spring, and disappears from the previous location in summertime, only to be seen again in autumn.

• Journal of Environmental Science International
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• v.11 no.4
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• pp.281-288
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• 2002

This study was carried out for reading the change of local meteorological environment according to dam construction of Nakdong-river using numerical model. The study used PSU/NCAR Mesoscale Model version5(MM5) for inquiring effect of formation of artificial lake after dam construction. The colleague simulated temperature mixing ratio, latent heat flux and sensible heat flux in two cause of existing lake and not. Temperature and mixing ratio in southwest of Andong lake increased because of the air that was warm and moist above the lake moved to southwest due to the northeasterly wind. In the case of existing lake around Andong, latent heat flux increased much in the daytime after sunrise. However, sensible heat flux decreased but it didn't change distinctly in southwest of Andong like the other values.

• Journal of Aquaculture
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• v.17 no.4
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• pp.258-261
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• 2004

The Oxygen consumption of hybrid striped bass (Morone chrysops ♀ M. saxatilis ♂) was measured in relation to water temperature, salinity and photoperiod changes. Fish (574.0101.3 g) was individually exercised in a chamber for 24 h at 2$0^{\circ}C$, 24$^{\circ}C$ and 28$^{\circ}C$ with two salinity conditions (0 and 33 psu). Stepwise, the increase of water temperature induced a strong increase of the oxygen consumption. Salinity and photoperiod had an influence on the oxygen consumption of hybrid striped bass, even though there was not a consistent tendency between those.

• Mycobiology
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• v.38 no.2
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• pp.108-112
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• 2010

To investigate the possible roles of LAMMER kinase homologue, Lkh1, in Schizosaccharomyces pombe, whole proteins were extracted from wild type and lkh1-deletion mutant cells and subjected to polyacrylamide gel electrophoresis. Differentially expressed proteins were identified by tandem mass spectrometry (MS/MS) and were compared with a protein database. In whole-cell extracts, 10 proteins were up-regulated and 9 proteins were down-regulated in the mutant. In extracellular preparations, 6 proteins were up-regulated in the lkh1+ null mutant and 4 proteins successfully identified: glycolipid anchored surface precursor, $\beta$-glucosidase (Psu1), cell surface protein, glucan 1,3-$\beta$-glucosidase (Bgl2), and exo-1,3 $\beta$-glucanase (Exg1). These results suggest that Lkh1 is involved in regulating cell wall assembly.

• Korean Journal of Digital Imaging in Medicine
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• v.13 no.1
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• pp.27-32
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• 2011

The conventional types of X-ray generators were bulky in physical size and heavy in weight, and the control accuracies of the output voltages were not always satisfactory. The high frequency switching inverter and converter technology on power conversion and control systems have been greatly closed up introducing power semiconductor devices. To decreasing the volume and the weight of high voltage transformer, and to stabilize ripple. In this paper, the newly developed x-ray generator in a low cost using duty modulation PWM inverter. This system verify improved performance by stabilize ripple of X-ray tube voltage and compared the reproducibility, linearity and dose in single phase, three phase and PSU.

• Proceedings of the KIPE Conference
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• 2008.10a
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• pp.143-145
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• 2008

최근 각종 전자기기의 슬림화 추세에 따라 PDP PSU(Power Supply Unit) 또한 슬림화가 진행되고 있다. 슬림화를 위해서는 방열판과 벌크(Bulk) 커패시터, 입력단의 필터와 인덕터류, 그리고 변압기의 높이를 줄이는 것이 중요하다. 그 중에서도 변압기의 높이를 줄이는 것이 가장 큰 관건이다. 하나의 변압기를 사용할 경우 슬림화의 한계성을 가지기 때문에 적용된 변압기는 두 개의 LLT 변압기로 구성 하였으며 1차측과 2차측의 결선 방법을 통해 두 LLT변압기간의 전류 불균형 문제를 최소화 할 수 있도록 하였다. 그리고 높이 35mm 시제품을 제작하여 50HD PDP 전원에 적용시켜 검증한 결과를 나타내었다.

• Proceedings of the KIPE Conference
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• 2008.10a
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• pp.146-149
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• 2008

최근 대기전력저감기능을 갖는 PWM IC를 적용한 플라이백 컨버터는 대기전력 모드 시 Burst 스위칭 동작에 의해 소모 전력을 최소화 할 수 있지만 경 부하 및 대기전력모드 시 변압기를 통해 흐르는 큰 여자전류에 의해 여전히 낮은 효율특성을 가지는 문제점이 있었다. 본 논문에서는 경 부하 및 대기전력모드 동작 시 변압기에 흐르는 여자전류를 최소화함으로 효율을 개선한 회로를 제안하였으며 50인치 PDP TV PSU (Power Supply Unit)에 있어서 대기전력 및 보조전원으로 사용된 74W 플라이백 컨버터에 적용하여 비교 검토하여 보았다.