• Title/Summary/Keyword: GSO

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A Study on the Impact of Interference from NGSO/FSS Networks on a GSO/FSS Network (정지궤도/고정위성업무 위성망에 대한 비정지궤도/고정 위성업무 위성망의 간섭 영향에 관한 연구)

  • 권태곤;강병수;박세경
    • Proceedings of the IEEK Conference
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    • 1999.11a
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    • pp.837-840
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    • 1999
  • It is difficult to analyze the impact of interference of NGSO/FSS systems on a GSO/FSS network because of time-varying nature of NGSO/FSS systems. In this paper, we present an efficient method to assess the impact of interference of NGSO/FSS satellite networks on the GSO/FSS carrier performances. The example analysis shows the impact on the GSO/FSS carrier performances in terms of elevation angles of earth stations in a GSO/FSS system.

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Ginseng seed oil ameliorates hepatic lipid accumulation in vitro and in vivo

  • Kim, Go Woon;Jo, Hee Kyung;Chung, Sung Hyun
    • Journal of Ginseng Research
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    • v.42 no.4
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    • pp.419-428
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    • 2018
  • Background: Despite the large number of studies on ginseng, pharmacological activities of ginseng seed oil (GSO) have not been established. GSO is rich in unsaturated fatty acids, mostly oleic and linoleic acids. Unsaturated fatty acids are known to exert a therapeutic effect in nonalcoholic fatty liver disease (NAFLD). In this study, we investigated the protective effect and underlying mechanisms of GSO against NAFLD using in vitro and in vivo models. Methods: In vitro lipid accumulation was induced by free fatty acid mixture in HepG2 cells and by 3 wk of high fat diet (HFD)-feeding in Sprague-Dawley rats prior to hepatocyte isolation. The effects of GSO against diet-induced hepatic steatosis were further examined in C57BL/6J mice fed a HFD for 12 wk. Results: Oil Red O staining and intracellular triglyceride levels showed marked accumulation of lipid droplets in both HepG2 cells and rat hepatocytes, and these were attenuated by GSO treatment. In HFD-fed mice, GSO improved HFD-induced dyslipidemia and hepatic insulin resistance. Increased hepatic lipid contents were observed in HFD-fed mice and it was lowered in GSO (500 mg/kg)-treated mice by 26.4% which was evident in histological analysis. Pathway analysis of hepatic global gene expression indicated that GSO increased the expression of genes associated with ${\beta}$-oxidation (Ppara, Ppargc1a, Sirt1, and Cpt1a) and decreased the expression of lipogenic genes (Srebf1 and Mlxipl), and these were confirmed with reverse transcription and quantitative polymerase-chain reaction. Conclusion: These findings suggest that GSO has a beneficial effect on NAFLD through the suppression of lipogenesis and stimulation of fatty acid degradation pathway.

The Analysis on the Interference Effects from Airship of HAPS system to Satellite of GSO system in Ka band (Ka 대역에서 HAPS 비행선으로부터 GSO 위성으로의 간섭 영향 분석)

  • 강영흥;최문환
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.5B
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    • pp.476-481
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    • 2004
  • Since the bands 27.5 ∼ 28,350㎓ and 31.0 ~ 31.30Hz for existing fixed-satellite service were allocated to tile HAPS system in WRC-2000, the analysis on the interference effects between the existing FSS/GSO system and FS/HAPS system should be needed. To do study on the interference effects between above two systems, we can consider two frequency operational conditions, one is the Reverse mode, the other is Forward mode. In this paper, we analyzed the interference effects from airship of HAPS systems to satellite of the GSO system in the case of Reverse condition mode due to the C/I criterion, the latitude of HAPS and transmitting power of HAPS airship. In future, these results will be vital data to share between HAPS and GSO systems.

Study on the Anti-aging Activity of Gentianae sino-ornata Ethanol Extract (용담화 에탄올 추출물의 항노화 작용 연구)

  • Choi, Hyung-Wook;Li, Shun-Hua;Kim, Eun-Joo;Kim, Soo-Kyung;Lee, Jang-Cheon;Lim, Kyu-Sang
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.28 no.2
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    • pp.1-12
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    • 2015
  • Objective : The goal of this study is to identify the effects of extract ofGentianae sino-ornata(GSO) on the anti-oxidative activity of skin.For this purpose, several functions of GSO were analyzed in terms of skin-lightening activity and wrinkle improvement. Methods : Cell viability was measured by neutral red (NR) assay, and GSO showed highly efficacy in DPPH radical scavenging activity. The level of tyrosinase and matrix metalloproteinase-1 (MMP-1) in media was analyzed by ELISA kit, and the expressions of p-JNK and p-ERK was measured by Western blot. To elucidate inhibitory effects of GSO on melanin synthesis, I determined the tyrosinase activity and melanin production in B16F10 cells. Results : MMP-1 production in UVB-stimulated HDF cells was inhibited by GSO treatments, and also GSO inhibited protein expression levels of p-JNK and p-ERK. GSO significantly reduced tyrosinase activity and melanin synthesis in B16F10 cells. Conclusions : From these results, GSO appears to be effective on skin elasticity increase, wrinkle improvement, whitening as anti-aging activity.

The Analysis on the Interference Effects from GSO Satellites into HAPS Ground station (GSO 위성으로부터 HAPS 지상국에 미치는 간섭 영향 분석)

  • 강영흥;최문환
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.3
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    • pp.523-528
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    • 2004
  • The bands 27.5 ∼ 28.35GHz and 31.0 ∼ 31.3GHz were allocated to the High Altitude Platform Station in WRC-2000. However, since these bands were already allocated to the existing fixed-satellite service, the analysis on the interference effects between the existing FSS/GSO system and FS/HAPS system should be needed. To do study on the interference effects between above two systems, we can consider two frequency operational conditions, one is the Reverse mode and the other Forward mode. In this paper, we considered the Forward mode as the frequency operational condition and analyzed the interference effect from a number of GSO satellites to HAPS ground station due to the I/N values, the latitude of HAPS and the satellite separation. In future, these results will be vital data to share between HAPS and GSO systems.

A Study of the Interference Varying from a NGSO network to a GSO Network according to NGSO Satellite Tracking Strategies (비정지궤도 위성망의 위성 선정 방식에 따른 정지궤도 위성망으로의 간섭량 변화에 대한 연구)

  • 강병수;권태곤;박세경
    • Proceedings of the IEEK Conference
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    • 1999.11a
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    • pp.841-844
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    • 1999
  • The interference situation from NGSO/FSS network to GSO/FSS network is more complicated than the situation between GSO networks because of the time varying orbital characteristics of NGSO systems. In this paper, the interference characteristics for several types of hand-over strategies are simulated and it is shown that the results should be useful in practical coordination of inter-network interference.

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Analysis of continuous curves of EPFDs between non-GSO/FSS and GSO/FSS (비정지궤도 위성시스템 및 정지궤도 위성시스템과의 등가전력속밀도 연속곡선 분석)

  • 장재철;양규식;정종혁
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.5 no.1
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    • pp.34-40
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    • 2001
  • The necessary of research is proposed about sharing between networks of the fixed-satellite service using non-geostationary satellites and other networks of the fixed-satellite service, interference criteria and calculation methods for the fixed-satellite service because WRC-2000 make a decision that the frequency bands l1/14GHz and 20/30GHz are available to system in the fixed-satellite service employing satellite in both geostationary and non-geostationary orbits. In the paper, four methodologies attempting to derive continuous curves of korea satellite network EPFD(equivalent power flux density) are used.

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A Study on the Frequency Sharing between HEO FSS System and GSO FSS Network in the 12GHz Band (12GHz 대역에서 HEO 위성시스템과 GSO 위성망간의 주파수 공유 방법 연구)

  • Lim, Sang-Hee;Seong, Hyang-Suk
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2003.11a
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    • pp.567-571
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    • 2003
  • Owing to the insufficient satellite resources such as frequency and orbit, the interest in the sharing of these resources has been increasing. ITU-R has been studying on the power limitation, the interference mitigation techniques etc. in order to facilitate the frequency sharing between different systems. Therefore, we studied on the interference mitigation techniques between HEO FSS system and GSO FSS network. We performed the simulation using four mitigation techniques and, based on the results of simulation, evaluated these techniques.

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Analysis on the Interference from Satellites to HAPS ground station for Sharing between HAPS and FSS (HAPS와 FSS간의 주파수 공유를 위한 위성과 HAPS 지상국간의 간섭 분석)

  • 최문환;강영흥
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2003.10a
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    • pp.610-614
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    • 2003
  • The bands 27.5 - 28.35GHz and 31.0 - 31.3GHz were allocated to the High Altitude Platform Station in WRC-2000. However, since these bands were already allocated to the existing fired-satellite service, the analysis on the interference effects between the existing FSS/GSO system and FS/HAPS system should be needed. To do study on the interference effects between above two systems, we can consider two frequency operational renditions, one is the Reverse mode and the other Forward mode. In this paper, we considered the Forward mode as the frequency operational condition and analyzed the interference effect from a number of GSO satellites to HAPS ground station due to the I/N values, the latitude of HAPS and the satellite separation. In future, these results will be vital data to share between HAPS and GSO systems.

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Analysis of a Simulated Optical GSO Survey Observation for the Effective Maintenance of the Catalogued Satellites and the Orbit Determination Strategy

  • Choi, Jin;Jo, Jung Hyun;Yim, Hong-Suh;Choi, Young-Jun;Son, Ju-Young;Park, Sun-youp;Bae, Young-Ho;Roh, Dong-Goo;Cho, Sungki
    • Journal of Astronomy and Space Sciences
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    • v.32 no.3
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    • pp.237-245
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    • 2015
  • A strategy is needed for a regional survey of geosynchronous orbits (GSOs) to monitor known space objects and detect uncataloged space objects. On the basis of the Inter-Agency Debris Committee's recommendation regarding the protected region of geosynchronous Earth orbit (GEO), target satellites with perigee and apogee of $GEO{\pm}200km$ and various inclinations are selected for analysis. The status of the GSO region was analyzed using the satellite distribution based on the orbital characteristics in publicly available two-line element data. Natural perturbation effects cause inactive satellites to drift to two stable longitudinal points. Active satellites usually maintain the designed positions as a result of regular or irregular maneuver operations against their natural drift. To analyze the detection rate of a single optical telescope, 152 out of 412 active satellites and 135 out of 288 inactive satellites in the GSO region were selected on the basis of their visibility at the observation site in Daejeon, Korea. By using various vertical view ranges and various numbers of observations of the GSO region, the detection efficiencies were analyzed for a single night, and the numbers of follow-up observations were determined. The orbital estimation accuracies were also checked using the arc length and number of observed data points to maintain the GSO satellite catalog.