• Nuclear Engineering and Technology
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• 제54권3호
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• pp.1024-1029
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• 2022

Composite scintillation screens on a base of Gd_1.2Y_1.8Ga_2.5Al_2.5O₁₂:Ce (GYAGG) scintillator have been evaluated for neutron detection. Besides the powdered scintillator, the composite includes ⁶LiF particles; both are merged with a binder and deposited onto the light-reflecting aluminum substrate. Results obtained demonstrates that screens are suitable for use with a silicon photomultiplier readout to create a prospective solution for a compact and low-cost thermal neutron sensor. Composite GYAGG/⁶LiF scintillation screen shows a pretty matched sensitivity and γ-background rejection with a widely used ZnS/⁶LiF screens however, possesses forty times faster response.

• 한국약용작물학회지
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• 제11권3호
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• pp.207-211
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• 2003

가시오갈피의 종자번식에서 가장 큰 문제점 중의 하나인 종자의 불량과 발아가 동시에 이루어지지 않는 문제를 해결하고 최대한 많은 묘목을 얻기 위해서는 파종시기의 선택이 중요하다. 파종 전 종자처리를 통하여 성숙정도가 다른 가시오갈피의 파종 후 유묘출현율과 최종생존율을 높이기 위한 기초자료를 얻기 위해 본 연구를 실시한 결과를 요약하면 다음과 같다. 1. $15^{\circ}C$에서 145일 충적 저장한 가시오갈피 성숙종자의 개갑율은 16.6%로 매우 저조하였다. 2. 개갑종자의 기내발아실험에서 $GA_{3}$처리는 최고로 26.6%의 발아율을 보였으나 발아는 동시기에 이루어지지 않았다. 3. 후숙처리후 10일간 저온 처리한 개갑종자에서 파종 전 $GA_{3}$처리는 유묘출현율을 높이는 효과가 있었으나 저온처리는 대체하지 못하였다. 4. 휴면타파를 위한 저온 충적저장전의 종자의 $GA_{3}$처리는 파종 시 개갑종자의 유묘출현율에 영향을 주지 못하였다. 5. 저온저장 40일 경과한 후 파종 전 $GA_{3}$처리는 비개갑종자에서는 유묘출현율과 생존율을 높였다. 개갑종자에서는 유묘출현율은 14.6% 증가하였지만 최종생존율은 오히려 9.4% 감소하였다.

• Journal of Acupuncture Research
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• 제24권6호
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• pp.207-213
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• 2007

Objectives : This study was designed to investigate the effect of SAAM-Acupuncture and GamigungguitangGaNokyong(GMGGTN) on Ankle Fracture. Methods : SAAM-Acupuncture was administered once daily. The following points were selected: $SP_3$(太白), $LU_9$(太淵), $LI_{11}$(曲池). After short leg casting, GMGGTN was taken 3 times per a day from March 28th to April 30th. We evaluated the patient using the Visual Analogue Scale(VAS) and Ankle Range of Motion(ROM). Results : After about 3 weeks of treatment, the patient's short leg cast was removed a week earlier than expected and the patient could walk without crutches and physical therapy. Their VAS changed from 10 to 1. And after added treatment for 2 weeks, there was no pain and limitation of ROM. Conclusions : According to the results, SAAM-Acupuncture and GMGGTN may have rapid effects on ankle fractures. But further studies are required to confirm this effect.

• Archives of Pharmacal Research
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• 제28권1호
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• pp.81-86
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• 2005

The hepatoprotective effects of chalcone derivatives were evaluated in D-galactosamine/lipopolysaccharide (D-GaIN/LPS)-induced fulminant hepatic failure in mouse. Thirteen chalcone derivatives were synthesized for study and their hepatoprotective effects were evaluated by assessing aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels in serum. Chalcone preparations were injected into mice at 12 hand 1 h before intraperitoneal injection of D-GaIN/LPS. After abdominal administration, changes in AST and ALT between the control and treated groups were observed. Ten of the synthesized chalcone derivatives exhibited inhibitory effects on D-GaIN/LPS-induced levels of AST and ALT in mice. Compounds 2, 3, 8, 9, and 12 markedly reduced serum AST and ALT at 8 h, inhibited hepatocyte necrosis and showed significant hepatoprotective activities. The activity of compound 3 was compared with the bifendate (DDB) through oral administration. Compound 3 showed much higher inhibitory effects than bifendate for decreasing AST and ALT activity. The results indicate that compound 3 has strong hepatoprotective activity through suppression of tumor necrosis factor­alpha (TNF-alpha) preduction, reduction of the histological change in the liver, and attenuated of hepatocyte apoptosis confirmed by DNA fragmentation assay.

• Plant Biotechnology Reports
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• 제3권4호
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• pp.285-292
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• 2009

Zoysiagrass (Zoysia japonica) is one of the important turfgrass species. Extending green period of zoysiagrass via delaying leaf senescence will make this species have more potential in the turfgrass industry. In this study, we found that zoysiagrass seedlings treated with $GA_3$ could delay the leaf senescence induced by darkness. To study expression of genes responsive to staying green in zoysiagrass, suppression subtractive hybridization (SSH) was used to identify differentially expressed genes between non-$non-GA_3-treated$ and $GA_3-treated$ seedlings subjected to darkness. A total of 307 ESTs were generated, of which 226 ESTs clustered into 54 contigs and 81 were singlets. Differentially expressed genes selected by subtractions were classified into six categories according to their putative functions generated by BLAST analysis. Expression of five selected genes, Met, SAM, V-ATPase, Cry (Cryptochrome gene), and An (diphthine synthase gene) were examined by RT-PCR and Real-time PCR. Both RT-PCR and Real-time PCR results demonstrated that the differential expressions of these genes were attributable to delaying senescence by exogenously applied gibberellic acid. This is the first genome-wide study of senescence in a species of turfgrass.

• Journal of Power Electronics
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• 제15권2호
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• pp.479-486
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• 2015

The application of soft-switching techniques is increasing in the DC/DC converter area. It is important to design soft-switching parameters to ensure the converter operates properly and efficiently. An optimized design method is presented in this paper. The objective function is the total power loss of a converter, while the variables are soft-switching parameters and the constraints are the electrical requirements for soft-switching. Firstly, a response surface methodology (RSM) model with a high precision is built, and the rough optimized parameters can be obtained with the help of a genetic algorithm (GA) in the solution space determined by the constraints. Secondly, a re-optimization is conducted with a SPICE model and a GA, and accurate optimized parameters can be obtained. Simulation and experiment results show that the proposed method performs well in terms of a wide adaptability, efficiency, and global optimization.

• Journal of Magnetics
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• 제21권1호
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• pp.12-19
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• 2016

The <100> oriented $Fe_{83}Ga_{17}$ alloys with various contents of NbC or B were prepared by directionally solidification method at the growth rate of $720mm{\cdot}h^{-1}$. With a small amount of precipitates, the columnar grains grew with cellular mode during directional solidification process, while like-dendrite mode of grains growth was observed in the alloys with higher contents of 0.5 at% due to the dragging effect of precipitates on the boundaries. The NbC precipitates disperse both inside grains and along the boundaries of $Fe_{83}Ga_{17}$ alloys with NbC addition, and the Fe2B secondary phase particles preferentially distribute along the grain boundaries in B-doped alloys. Precipitates could affect grain growth and improved the <100> orientation during directional solidification process. Small amount of precipitate element addition slightly increased the magnetostrictive strain, and a high value of 335 ppm under pre-stress of 15 MPa was achieved in the alloys with 0.1 at% NbC. Despite the fact that the effect on magnetic induction density of small amount of precipitates could be negligible, the coercivity markedly increased with addition of precipitate element for $Fe_{83}Ga_{17}$ alloy due to the retarded domain motion resulted by precipitates.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.406-407
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• 2009

In this paper, presents the Wilkinson power divider used integrated passive device (IPD) technology with excellent performance for personal communication services (PCS). The insertion loss of this power divider is 0.4 dB and the port isolation greater than 25 dB over the entire band. Return losses input and output ports are 18 dB and 19 dB, respectively. The power divider based on SI-GaAs substrate is designed within die size of about $0.775\times0.53\;mm^2$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.385-386
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• 2008

In this paper, a simple dual band filter chip is designed with 0603 case size using IPD technology. The dual-band filter achieves high frequency band at 2.5 GHz and low frequency band at 1.8 GHz. The insertion losses in high frequency band and low frequency band are -0.195 dB and -0.146 dB, respectively. The return losses in these bands are -22.7 dB and -22.8 dB, respectively. The simple dual-band filter based on SI-GaAs substrate is designed within die size of about 1.3 $mm^2$.

• Journal of the Optical Society of Korea
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• 제20권1호
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• pp.169-173
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• 2016

Terahertz (THz) generation by a GaP ridge waveguide with a collinear modal phase-matching scheme based on cascaded difference frequency generation (DFG) processes is theoretically analyzed. The cascaded Stokes interaction processes and the cascaded anti-Stokes interaction processes are investigated from coupled wave equations. THz intensities and quantum conversion efficiency are calculated. Compared with non-cascaded DFG processes, THz intensities from 11-order cascaded DFG processes are increased to 5.48. The quantum conversion efficiency of 177.9% in cascaded processes can be realized, exceeding the Manley-Rowe limit.