• Proceedings of the KIEE Conference
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• 2008.10a
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• pp.83-84
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• 2008

인구의 증가로 인한 전력수요의 증가는 가공 및 지중 송진설비의 대용량화로 이어져왔다. 그러나 최근 도시 경관과 전자파로 인한 건강 등에 대한 관심이 급증하면서 주거지 주변 송전선로 실리에 대한 민원이 증가하고 있다 을에 대한 대안으로 대용량 전력송전이 가능하고 가공 및 지중송전의 단점을 보완한 가스결연 송전선로(Gas Insulated Transmission Line, GIL)가 개발되었다. 선진국에서는 가스 절연으로 우수한 절연성능과 안정성을 가지며, 기존 교통용 터널 또는 지하 전력구에 설치함으로써 주변 경관을 해치지 않고 낮은 전계 형성 등의 장점을 가진 가스절연송전선로의 연구와 개발에 많은 노력 기울이고 있다[$1{\sim}5$]. 본 논문에서는 전력기기들의 결함진단에 많이 사용되는 부분방전 측정을 가스절연 송전선로에 적용할 수 있는 최적의 측정용 센서를 개발하여 유사한 구조를 가지는 75kV GIS Mock-up과 Free moving particle 모의 방전 셀을 이용하여 발생시킨 부분방전 신호를 측정하여, 광대역 특성을 보이는 대수주기 패치 안테나와의 성능을 비교하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.454-458
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• 2007

Nonpoint source (NPS) pollution is a serious problem causing the degradation of soil and water quality. Concentrated overland flow is the primary transport mechanism for a large amount of NPS pollutants from hillslope areas to downslope areas in a watershed. In this study, a soil erosion model, nLS model, to identify transitional overland flow regions (i.e., ephemeral gully head areas) was developed using the kinematic wave overland flow theory. Spatial data, including digital elevation models (DEMs), soil, and landcover, were used in the GIS-based model algorithm. The model was calibrated and validated using gully head locations in a large agricultural watershed, which were identified using 1-m aerial photography. The model performance was better than two previous approaches; the overall accuracy of the nLS model was 72 % to 87 % in one calibration subwatershed and the mean overall accuracy was 75 to 89 % in four validation subwatersheds, showing that the model well predicted potential transitional erosion areas at different watersheds. However, the user accuracy in calibration and validation was still low. To improve the user accuracy and study the effects of DEM resolution, finer resolution DEMs may be preferred because DEM grid is strongly sensitive to estimating model parameters. Information gained from this study can improve assessing soil erosion process due to concentrated overland flow as well as analyze the effect of microtopographic landscapes, such as riparian buffer areas, in NPS control.

• Journal of the Society of Naval Architects of Korea
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• v.40 no.6
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• pp.1-11
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• 2003

For an accurate shock response analysis of a floating structure such as a naval surface ship subjected to an UNDEX(UNDerwater Explosion), the cavitation effects due to reflected wave at free surface and wetted structural surface should be considered. In this study, for the consideration of cavitation effects an effective method using LS-DYNA/USA and its theoretical background were presented. Through the application of the analysis of bulk cavitation phenomena in the free field, it could be confirmed that almost the same results were obtained between LS-DYNA/USA code and the analytical method. for the investigation of cavitation effects from the structural shock response characteristics, three dimensional UNDEX shock response analysis of an idealized ship model was also carried out It could be found that the cavitation Phenomena gave significant effects on the structural shock response characteristics, and especially that the shock loadings calculated at the installed location of shipboard equipment were underestimated in the case of no consideration of the cavitation effects, which might cause the severe mistake in its shock-resistance design.

• Journal of Magnetics
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• v.4 no.1
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• pp.5-9
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• 1999

Effect of sulfur segregation on tertiary recrystallization and magnetic induction during final annealing was investigated in a 3% Si-Fe electrical strip containing 6 ppm(LS) and 15 ppm(HS) sulfur. During final annealing, Auger peak height of segregated sulfur on the surface of the strips reached a maximum, and then decreased to low level with increasing annealing time, which is attributed to sulfur segregation and evaporation. The magnetic induction of the thin-gauged 3% Si strip was inversely proportional to the Auger peak height of segregated sulfur on the surface. The overall profile for surface segregation of sulfur and B10 was observed, irrespective of sulfur content in Si-Fe strips, but the peaks of LS strips appeared earlier than those of HS strips. The grain growth rate of the LS strips during final annealing was faster than that of the HS strips, which may be attributed to the pinning effects of segregated sulfur. With increasing final annealing temperature, B10 value increased rapidly and the saturation level in B10 increased.

• Korean Journal of Plant Resources
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• v.25 no.3
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• pp.323-328
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• 2012

This paper describes the potential use of deep sea water to stimulate seed germination in both common and Tartary buckwheat. Treatment of 10% deep sea water at $25^{\circ}C$ would slightly enhance germination of buckwheat seeds compared to non-DSW treatment and other temperature. In this study, the significant effects of photoperiod and temperature on seedling growth were also found in the HL treatment for the number of leaf, plant height, and plant fresh weight and LL treatment for root length and leaf size. Common buckwheat (Suwon No.1) showed higher rate (93%) of flowering plants in the HS and LL (93% of flowering rates) than those revealed in the HS and LS treatment, while the low percentage(67%) of plant flowering plants was shown in the LS treatment. All plants (100%) of a Korean landrace, Ahndong-jaerae showed flowers in the HS and LS treatment. HL and LL treatment status did not occur in the plant's flowering. Any Tartary buckwheat (KW45) plant did not yet flowered when it was 21 days-old.

• The Transactions of the Korean Institute of Power Electronics
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• v.26 no.5
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• pp.364-371
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• 2021

A magnetic flux saturation model of Synchronous Reluctance Motors (SynRMs) and a parameter estimation method are proposed at standstill. The proposed magnetic flux model includes the nonlinear relationship between the current and the magnetic flux for self-saturation and cross-saturation. Voltage is injected at standstill to estimate the magnetic flux saturation model. Voltages are injected into the d-axis and q-axis to obtain data on self-saturation. Subsequently, voltages are simultaneously injected into the d-q axis to obtain data on cross-saturation. On the basis of the measured current and the calculated magnetic flux, the parameters of the proposed model are estimated using the least square method (LSM). Simulation and experiment were performed on a 1.5-kW SynRM to verify the proposed method. The proposed model can be used to create a high-efficiency operation table, a sensorless algorithm, and a current controller to improve the control performance of a motor.

• Journal of Veterinary Science
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• v.23 no.6
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• pp.91.1-91.9
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• 2022

Three parameters, body weight gain (BWG), intestinal lesion score (LS) and fecal oocyst shedding, were compared in broilers infected with major parasitic species; Eimeria acervulina, E. maxima, and E. tenella. First, two- and three-week-old chickens with Eimeria infection showed LS of approximately 3, but two-week-old chickens were more correlated with BWG. Second, significant differences in BWG were observed between male and female broilers challenged with Eimeria. Finally, E. maxima-infected broilers among three Eimeria species showed a higher relationship between BWG and LS, suggesting three considerations such as genders, age and Eimeria species for Eimeria experiments.

• Journal of Nutrition and Health
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• v.37 no.1
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• pp.52-60
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• 2004

This study was conducted to investigate the bone mineral density (BMD) and the anthropometric measurements, socioeconomic factors, family history of osteoporosis and other environmental factors affecting BMD in children. One hundred sixty children (80 males, 80 females) in second grade of elementary school in Seoul were recruited; the mean age was 7.7 $\pm$ 0.47 years. Bone mineral density was measured in the lumbar spine (LS), femoral neck (FN), femoral trochanter (FT), and Ward's triangle (WT) by Dual Energy X-ray Absorptiometry (DEXA). Socioeconomic factors, family history of osteoporosis, and other environmental factors were assessed by questionnaire. Bone mineral densities of LS, FN, FT, and WT were 0.677, 0.637, 0.618, and 0.658 g/$\textrm{cm}^2$. BMD of boys was higher than that of girls (LS: 0.685 vs. 0.669, FN: 0.660 vs. 0.614, FT: 0.632 vs. 0.604, WT: 0.678 vs. 0.639 g/$\textrm{cm}^2$). Anthrometric measurements (height, weight relative body weight, circumference of waist and hip) were positively correlated with BMD. With increasing family income, BMD of LS was significantly lowered, and negative correlation was observed between mother's age at birth of subject and the BMD of FN. And the BMD of children with a family history of osteoporosis was significantly lower. However BMDs were not different by educational level of parents, family pattern, delivery term, birth weight, and type of feeding. Further studies are needed to clarify the factors affecting BMD of children and earlier age, included infants and even prenatal life. If any association is revealed and persist until the attainment of peak bone mass, osteoporosis prevention programs are needed to be start very early in the life cycle.

• BMB Reports
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• v.45 no.12
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• pp.730-735
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• 2012

p13 gene was first described in Leucania separata multinuclear polyhedrosis virus (Ls-p13) several years ago, but the function of P13 protein has not been experimentally investigated to date. In this article, we indicated that the expression of p13 from Heliothis armigera single nucleocapsid nucleopolyhedrovirus (Ha-p13) was regulated by both early and late promoter. Luciferase assay demonstrated that the activity of Ha-p13 promoter with hr4 enhancer was more than 100 times in heterologous Sf9 cells than that in nature host Hz-AM1 cells. Both Ls-P13 and Ha-P13 are transmembrane proteins. Confocal microscopic analysis showed that both mainly located in the cytoplasm membrane at 48 h. Results of RNA interference indicated that Ha-p13 was a killing-associated gene for host insects H. armigera. The AcMNPV acquired the mentioned killing activity and markedly accelerate the killing rate when expressing Ls-p13. In conclusion, p13 is a killing associated gene in both homologous and heterologous nucleopolyhedrovirus.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.15
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• pp.6263-6267
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• 2014

Background: It is standard treatment to combine chemotherapy (CT) and thoracic radiotherapy (TRT) in treating patients with limited stage small cell lung cancer (LS-SCLC). However, optimal timing of TRT is unclear. We here evaluated the survival impact of early versus late TRT in patients with LS-SCLC. Materials and Methods: Follow-up was retrospectively analyzed for seventy consecutive LS-SCLC patients who had successfully completed chemo-TRT between January 2006 and January 2012. Patients received TRT after either 1 to 2 cycles of CT (early TRT) or after 3 to 6 cycles of CT (late TRT). Survival and response rates were evaluated using the Kaplan-Meier method and comparisons were made using the multivariate Cox regression test. Results: Median follow-up was 24 (5 to 57) months. Carboplatin+etoposide was the most frequent induction CT (59%). Median overall, disease free, and metastasis free survivals in all patients were 15 (5 to 57), 5 (0 to 48) and 11 (3 to 57) months respectively. Late TRT was superior to early TRT group in terms of response rate (p=0.05). 3 year overall survival (OS) rates in late versus early TRT groups were 31% versus 17%, respectively (p=0.03). Early TRT (p=0.03), and incomplete response to TRT (p=0.004) were negative predictors of OS. Significant positive prognostic factors for distant metastasis free survival were late TRT (p=0.03), and use of PCI (p=0.01). Use of carboplatin versus cisplatin for induction CT had no significant impact on OS (p=0.634), DFS (p=0.727), and MFS (p=0.309). Conclusions: Late TRT appeared to be superior to early TRT in LS-SCLC treatment in terms of complete response, OS and DMFS. Carboplatin or cisplatin can be combined with etoposide in the induction CT owing to similar survival outcomes.