• YAKHAK HOEJI
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• v.48 no.5
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• pp.291-296
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• 2004

Sparganium stoloniferum Buch.-Ham. (Sparganiaceae) is a perennial herb which has been used as treatments for menstrual disorder, galactagogue and endometriosis in folk remedies. The Sparganii Rhizoma processed, heated with vinegar, used to different purpose compared with origin in medicine. In order to estimate the different effects between processed (PSR) and unprocessed (USR) Sparganii Rhizoma, extraction and systemic fractionation of the rhizomes were archived. Inhibitory effects of the extracts as well as the fractions of PSR and USR on rat lens aldose reductase and on rat platelet aggregation were investigated for the prevention or the treatment of chronic diabetic complications. Their antioxidant effects, measured using lipid peroxidation of liver tissue and radical scavenging activities on 1,1-diphenyl-picrylhydrazyl in vitro, were evaluated. The most of biological activities tested except rat platelet aggregation, fractions from PSR were shown to exhibit stronger activities than those from USR. It seems that caused by changing of the chemical components by heating process in conditioned with acetic acid. Compounds isolated were shown to significant inhibitory activity on rat lens aldose reductase. Inhibitory activity of compounds isolated on rat lens aldose reductase have been tested in vitro. $IC_{50}$/ (6.31 $\mu$M) of cerebroside I (V) was nearly equal to that (6.32 $\mu$M) of a reference compound, tetrametbylene glutaric acid (TMG).

• The Transactions of the Korean Institute of Power Electronics
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• v.28 no.1
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• pp.30-38
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• 2023

In this paper, a constant current(CC) and constant voltage(CV) control method using a primary-side regulated(PSR) fly-buck converter is proposed. Because the primary-side structure of the fly-buck converter is the same as that of the synchronous buck converter, it always operates in continuous conduction mode(CCM). Therefore, in the proposed method, the load information on the secondary side can always be easily estimated by measuring the primary inductor current at the midpoint of the switch-on period. An accurate CC/CV control can be achieved through simple calculations based on this estimated information. Consequently, the proposed method is advantageous for optimizing the control performance of the PSR converter. The validity of the proposed control was verified using a 5 W prototype of a PSR fly-buck converter. The experimental results confirmed that the current reference of 500 mA was followed within the error range of 1.2%, and that the voltage reference of 12 V was followed within the error range of 1.8% despite the indirect control of the load current and output voltage from the primary side.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4B
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• pp.329-334
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• 2006

The spatial variability of the L- and C- band large scale remotely sensed soil moisture data, obtained during the Southern Great Plain 1999 Experiment (SGP'99), was characterized. The results demonstrate that soil moisture data using L-band show the break in statistical symmetry (multiscaling behavior) with the variation of scale of observation, which is similar to that of the soil property such as sand content. Also, soil moisture data using C-band show single scaling behavior with the variation of scale of observation, which is similar to that of the vegetation condition. The results should be considered during downscaling the Global soil moisture data using AMSR instrument.

• IEIE Transactions on Smart Processing and Computing
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• v.4 no.3
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• pp.152-157
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• 2015

Various power supply noise sources in a system integrated circuit degrade the performance of a low dropout (LDO) regulator. In this paper, a capacitor-less low dropout regulator for enhanced power supply rejection is proposed to provide good power supply rejection (PSR) performance. The proposed scheme is implemented by an additional capacitor at a gate node of a pass transistor. Simulation results show that the PSR performance of the proposed LDO regulator depends on the capacitance value at the gate node of the pass transistor, that it can be maximized, and that it outperforms a conventional LDO regulator.

• Nuclear Engineering and Technology
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• v.10 no.4
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• pp.203-213
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• 1978

A combination of computer codes such as LATREP, HWR, AXAV and CITATION is utilized in an attempt to analyze the nuclear design characteristics of the CANDU-PHWR of the Wolsung Unit 1. The major nuclear properties to be computed are tile lattice properties of CANDU fuel channel and the core channel power distribution. The computed results are compared with the PSR documentation for the Wolsung reactor. The observed discrepancies between our computation and the PSB values are discussed in terms of incomplete information on the description of the core configuration in the PSR and the different calculation methods.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.385-387
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• 2005

Polarimetric measurements of the sky radiation by the PSR-I000, which is the multi-spectral polarimeter developed by the Opt Research Corporation and has the same wavelength regions (443nm, 490nm, 565nm, 670nm, 765nm and 865nm) as the ADEOSII/POLDER sensor, have been carried out at the ground station in Kanazawa city, Japan from March to May. First of all, the wavelength dependency of degrees of polarization is examined and it is shown that degrees of polarization measured under the hazy dust cloud are lower than those measured in the clear sky and decrease as the wavelength increases. Next, a new method for estimating optical properties, such as the optical thickness, the number size distribution and the refractive index, of the Asian dust and the ground reflectance from degrees of polarization measured by PSR-I000 is described. Finally, this method is applied to polarization data acquired on April 15,2002. As a result, it is shown that our estimation algorithm provides a good result.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.55.2-55.2
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• 2018

Neutron stars (NS) are rapidly spinning compact objects. Their rotation energy is released by particles, electromagnetic waves, and even gravitational waves. The source of the energy is of course the rotation, so by studying the rotational properties of neutron stars, we can gain some insights into matter under extreme conditions. In particular, it is known that the braking index n is sensitive to the moment of inertia and/or NS winds. The neutron star PSR B0540-69 exhibits interesting timing behavior; previous measurements of the braking index for this pulsar may suggest a change in time. In order to see if the change is real, We investigate the timing properties of B0540-69 using recent ~1000-days Swift satellite data.

• Journal of Radiation Protection and Research
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• v.28 no.4
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• pp.349-351
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• 2003

To ensure the safety of the currently operating nuclear power plant, the Periodic Safety Review program has been conducted. In PSR program, the cumulative behavior of the radionuclide that might be released from the power plant is addressed. The Cs-137 in soil around Kori nuclear power plant was investigated. The soil sample was analyzed and compared with the reference area. The model calculation explained the depth profile of Cs-137.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1016-1017
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• 2015

본 논문은 최근 에너지 절약의 중요성이 커지면서 많은 관심을 가지고 있는 1차측 제어(PSR : Primary Side Regulation) Flyback 컨버터에 관한 연구이다. 낮은 부하 상태에서의 전원장치의 전력변환 효율을 증가시키기 위해서는 전력손실회로의 제거 및 대체가 중요하다. 본 논문에서는 낮은 부하 상태에서 상대적으로 전력소모가 큰 2차측 제어회로를 제거하고 보조권선 전압에 반영된 출력전압의 정보를 검출, 보존하도록 하여 Flyback 컨버터의 제어기 구현이 가능하도록 하는 출력전압 정보 검출회로를 설계하였다. 회로의 설계 및 검증은 Magnachip 0.35um, 700V CMOS 공정을 이용하였다.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.932-933
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• 2015

This paper presents methods to achieve and control accurate output voltage. PSR removed secondary output voltage sensing circuit, therefore standby power loss can be decreased. When sensing the auxiliary winding voltage, sensing must be done at accurate branch which has $V_O$ information. For this reason this paper presents the PSR sensing technique using sawtooth wave and peak detector. Circuit verification carried out with Spectre in Cadence corporation and Manga/Hynix $0.35{\mu}m$ 700V process.