• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.80.3-81
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• 2021

RR Lyrae variables are excellent distance indicators thanks to their visual magnitude-metallicity relation and well-defined Period-Luminosity Relations (PLRs) at infrared wavelengths. These population II variables together with the tip of the red giant branch provide primary calibration for the first-rung of the population II distance ladder. We will present new empirical calibration of RR Lyrae PLRs at near-infrared wavelengths using our data from the ongoing CFHT-WIRCam RR Lyrae program. We will discuss the systematic uncertainties involved in the calibration of these relations based on the latest Gaia EDR3 parallaxes and the implication for the cosmic distance scale.

• Korean Journal of Poultry Science
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• v.25 no.4
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• pp.195-202
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• 1998

The present study was conducted to investigate the effects of dietary supplemental dry powder of Rehmannia radix (RR) root on the growth performance and physiological status of broiler chicks. The treatments consisted of corn-soybean meal control diet, and RR 0.5, 1, and 2％ diets. A total of 160 Arbor Acre male broiler chicks were randomly allotted to 16 pens ; four pens per treatment and 10 birds per pen. The growth performance, feed intake and carcass weight did not show any differences among the treatment groups, but feed conversion was significantly lower (P< 0.05) in RR 1％ group than that of the control group. The muscle color was lighter (P < 0.05) in RR lof group than those of the other treatment groups. The blood concentrations of protein, glutamic-oxaloacetic-transaminase (GOT) and glutamic- pyruvic-transaminase (GPT) were not different (P > 0.05) among the treatment groups, but the blood total cholesterol content was significantly decreased (P < 0.05) in RR 2％ group than those the other treatment groups. The blood concentration of sugar was lower (P <0.05) in RR 2％ group than those of the other treatment groups, and hemoglobin concentration was decreased (P <0.05) by addition RR. Crude fat content of thigh muscle was higher in RR 1％ group than those of the other treatment groups, and bone hardness of broiler chicks fed RR was higher (P < 0.05) than that of the control group. The saturated fatty acid content of the thigh muscle tende to be high in control and RR 0.5％ groups, and unsaturated fatty acid content tende to be high in RR 1 and 2％ groups than those of the other treatment groups

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.2
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• pp.233-242
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• 2018

Previous works for detecting arrhythmia have mostly used nonlinear method such as artificial neural network, fuzzy theory, support vector machine to increase classification accuracy. Most methods require higher computational cost and larger processing time. Therefore it is necessary to design efficient algorithm that classifies PVC(premature ventricular contraction) and decreases computational cost by accurately detecting feature point based on only R peak through optimal R wave. For this purpose, we detected R wave through optimal threshold value and extracted RR interval and R peak pattern from noise-free ECG signal through the preprocessing method. Also, we classified PVC in realtime through RR interval and R peak pattern. The performance of R wave detection and PVC classification is evaluated by using 9 record of MIT-BIH arrhythmia database that included over 30. The achieved scores indicate the average of 99.02% in R wave detection and the rate of 94.85% in PVC classification.

• Korean Journal of Pharmacognosy
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• v.45 no.1
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• pp.28-34
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• 2014

Rhei Rhizoma (RR) and Moutan cortex (MC) have been reported to have anti-inflammatory effects. However, little is known about the effects of RR and MC on endothelial inflammation and insulin resistance (IR). This study aims to investigate whether the water extracts of RR and MC could exert protection against palmitic acid (PA)-induced inflammation and IR in human umbilical vein endothelial cells (HUVECs). HUVECs were pretreated for 6 h with RR or MC, and then exposed to PA for 24 h. The levels of interleukin-6 (IL-6) and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) were determined by enzyme-linked immunosorbant assay kits. Western blot analysis was performed for activation of nuclear factor-${\kappa}B$ (NF-${\kappa}B$) and insulin receptor substrate-1 (IRS-1). In HUVECs stimulated with PA, both RR and MC significantly inhibited the production of TNF-${\alpha}$ and IL-6 and the activation of NF-${\kappa}B$. At the same concentrations, the inhibitory effects of RR were more potent than those of MC. PA reduced insulin-induced phosphorylation of IRS-1, which was reversed by RR and MC. The results suggest that RR and MC are effective in inhibiting PA-associated endothelial inflammation and ameliorating IR by beneficial regulation of NF-${\kappa}B$ and IRS-1 activation.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.7
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• pp.4273-4278
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• 2013

Objective: We aimed to define clinicopathologic risk factors associated with regional recurrence (RR) and thus the effectiveness of postoperative radiotherapy (PORT) for neck control for head and neck squamous cell carcinomas (HNSCCs) with differing cervical lymph node status. Methods: A retrospective study was performed in 196 HNSCC patients with pathologically positive neck node (N+) to evaluate the high-risk factors for RR and to define the role of PORT in control after neck dissection and postoperative radiotherapy (PORT). Results: Overall, the RR rate after neck dissection and PORT was 29%. Extracapsular spread (ECS) was confirmed to be the only independent risk factor for RR. There were no significant risk factors associated with RR in the ECS- group. The 5-year disease-specific survival rate was 45%, which descended to 10% with the emergence of RR. Conclusions: ECS remains a determined risk factor for RR after neck dissection and PORT in patients with N+. PORT alone is not adequate for preventing RR in the neck with ECS after neck dissection. More intensive postoperative adjuvant therapies, especially combined chemotherapy and radiotherapy, are needed to prevent regional failure in HNSCC patients with ECS.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.10
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• pp.1542-1549
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• 2018

Objective: Because lactation periods in dairy cows lengthen with increasing total milk production, it is important to predict individual productivities after 305 days in milk (DIM) to determine the optimal lactation period. We therefore examined whether the random regression (RR) coefficient from 306 to 450 DIM (M2) can be predicted from those during the first 305 DIM (M1) by using a RR model. Methods: We analyzed test-day milk records from 85,690 Holstein cows in their first lactations and 131,727 cows in their later (second to fifth) lactations. Data in M1 and M2 were analyzed separately by using different single-trait RR animal models. We then performed a multiple regression analysis of the RR coefficients of M2 on those of M1 during the first and later lactations. Results: The first-order Legendre polynomials were practical covariates of RR for the milk yields of M2. All RR coefficients for the additive genetic (AG) effect and the intercept for the permanent environmental (PE) effect of M2 had moderate to strong correlations with the intercept for the AG effect of M1. The coefficients of determination for multiple regression of the combined intercepts for the AG and PE effects of M2 on the coefficients for the AG effect of M1 were moderate to high. The daily milk yields of M2 predicted by using the RR coefficients for the AG effect of M1 were highly correlated with those obtained by using the coefficients of M2. Conclusion: Milk production after 305 DIM can be predicted by using the RR coefficient estimates of the AG effect during the first 305 DIM.

• Journal of Bio-Environment Control
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• v.11 no.4
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• pp.199-204
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• 2002

To overcome a decrease of Korean ginseng production caused by successive cropping, we have tried to develop a nutrient culture system for Korean ginseng production. For determining the optimal substrate, mixture of sand and TKS-2 (S＋T), peatmoss (P), reused rockwool (RR), and granular rockwool (GR) were investigated. The overall physico-chemical properties of RR fell into the reported optimal range for the ginseng cultivation. However, bulk density of S＋T was a little higher than that of soil in Korean ginseng fields. The top fresh weight of the ginseng was high in RR and S＋T substrates. The root fresh and dry weights in the RR were remarkably greater than that in the conventional soil (CS) of Korean ginseng fields. In terms of ginseng quality, the vitamin C content of ginseng root in nutrient culture was higher than that in CS. However, the contents of crude saponin and total ginsenosides in ginseng between in the nutrient culture and in the soil culture did not show any significant differences.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1643-1646
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• 1997

In this study, the method is proposed, which enable us to noninvasively assess baroreflex sensitivity through the closed-loop feedback modle between RR flucturarion and arterial blood pressure fluctuation. The proposed indexes of baroreflex sensitivity, BRS$_{LF}$와 BRS$_{HF}$ are calculated by the modulus (or gain) of the transfer function between fluctuatuons in blood pressure and RR interval in the LF band HF band, where the coherence is more than 0.5 to evaluate the performance of the proposed method, it is applied to various cardiovascular variability signals obtained form subjects under the submaximal ecericse on bicycle ergometner. In result it is concluded that the proposed method can noninvasively assess the baroreflex sensitivity.ty.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2003.07a
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• pp.267-271
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• 2003

IETF mobileip WG에서 MN(Mobile Node)의 위치를 나타내는‘바인딩정보’를 안전하게 CN(Correspond Node)에게 송신하여 최적경로를 설정하는 RR(Return Routability)프로토콜을 드래프트 문서로 제안하고 있다［1］. 하지만 이 프로토콜은 최적경로설정이 MN에 의해 시작됨에 따라 최적경로설정 지연에 따른 최적경로설정 확률의 저하와 불필요한 메시지 교환에 따른 통신부담을 문제점으로 지적할 수 있다. 본 논문에서는 상기와 같은 문제점 해결방안으로 HA(Home Agent)가 CN으로부터 첫번째 패킷을 수신했을 때 최적경로설정을 시작하도록 개선된 RR프로토콜을 제안하였다. 이를 통해서 최적경로 설정에 소용되는 시간을 단축하고 교환되는 메시지 수를 감소시켜 통신부담 경감효과를 얻을 수 있다. 이럼에도 불구하고 기존의 RR프로토콜과 동일한 보안수준을 제공한다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.373-376
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• 2004

전력전자 회로의 고속화에 따라 정류기의 역할은 점차 중요해지고 있다. 전원장치의 compact화 및 초소형화에 따라 스위칭 주파수는 높아지고 있다. 최근 전원장치의 on-line 뿐만 아니라 off-line에서의 효율을 향상시키려면 도통손실 및 스위칭 손실을 최소화를 요구받고 있다. 스위칭 주파수가 증가함에 따라 power rectifier는 도전 및 스위칭 손실의 최소화를 위해서는 스위칭 손실의 주된 원인인 역회복 특성을 잘 파악해야 한다. 이를 위해 본 고에서는 최근 제작된 SiC SBD의 역회복 특성을 분석을 위한 $t_{rr}$, 측정을 위한 $t_{rr}$ Tester를 MIL-STD-750-4031.4에 참고하여 제작하였으며, 제작된 $t_{rr}$ Tester를 이용하여 SiC SBD의 $t_{rr}$의 측정결과에 대해 기술하였다.