• Title/Summary/Keyword: GEO

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Protection against Whole Body γ-Irradiation Induced Oxidative Stress and Clastogenic Damage in Mice by Ginger Essential Oil

  • Jeena, Kottarapat;Liju, Vijayasteltar B;Ramanath, Viswanathan;Kuttan, Ramadasan
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.3
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    • pp.1325-1332
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    • 2016
  • Radioprotective effects of ginger essential oil (GEO) on mortality, body weight alteration, hematological parameters, antioxidant status and chromosomal damage were studied in irradiated mice. Regression analysis of survival data in mice exposed to radiation yielded LD50/30 as 7.12 and 10.14 Gy for control (irradiation alone) and experimental (GEO-treated irradiated) mice, respectively, with a dose reduction factor (DRF) of 1.42. In mice exposed to whole-body gamma-irradiation (6 Gy), GEO pre-treatment at 100 and 500 mg/kg b.wt (orally) significantly ameliorated decreased hematological and immunological parameters. Radiation induced reduction in intestinal tissue antioxidant enzyme levels such as superoxide dismutase, catalase, glutathione peroxidase and glutathione was also reversed following administration of GEO. Tissue architecture of small intestine which was damaged following irradiation was improved upon administration of GEO. Anticlastogenic effects of GEO were studied by micronuclei assay, chromosomal aberration and alkaline gel electrophoresis assay. GEO significantly decreased the formation of micronuclei, increased the P/N ratio, inhibited the formation of chromosomal aberrations and protected agaisnt cellular DNA damage in bone marrow cells as revealed by comet assay. These results are supportive of use of GEO as a potential radioprotective compound.

The Design and Implementation of Festival Information Website using the GeoRSS Function (GeoRSS기능을 활용한 축제정보 사이트 구축)

  • Cho, A-Ra;Kang, Young-Ok
    • Spatial Information Research
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    • v.18 no.1
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    • pp.89-99
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    • 2010
  • This study has been implemented a map-based festival information website with Google Map to overcome a limit that existing festival information web sites supplied location information only through text-based format. To get the newest festival information, this website uses GeoRSS function which transform rss feed offered by newspaper websites into location based information. Through this function, internet users can see festival information at a glance on the basis of a map. Through this study we confirmed the efficiency of offering location based festival information and possibility of GeoRSS function to provide the newest festival information.

Estimation of Nitrogen Mass Balance in Sihwa-ho Watershed, 2010 (2010년 시화호유역 질소 물질수지 산정)

  • Choi, Jung-Kil;Lee, Hyo-Jin;Kim, Tea-ha;Choi, Jea-hun;Woo, Jun-Sik;Lee, Kang-Wung
    • Journal of Environmental Science International
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    • v.27 no.3
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    • pp.179-193
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    • 2018
  • Nitrogen budgets in Sihwa-ho in 2010 were estimated using a mass balance approach. Major nitrogen fluxes sources can be divided into three sections: cities, agricultural area, and forest. Surplus nitrogen 2,030~2,214 ton/yr (2,123 ton/yr in average) was discharged to Sihwa Lake. 20% of the surplus nitrogen is removed from the wetland and 60% is removed tidal flats. Therefore net nitrogen discharge from Sihwa basin is estimated to be 650~708 ton/yr (679 ton/yr in average). Wet and dry nitrogen deposition and load from non-point sources ware estimated to be 97 ton/yr and 69 ton/yr, deposition is using CAMx model. So estimated total nitrogen discharge into Sihwa-ho was 817~875 ton/yr (846 ton/yr in average). The atmospheric load explains 11.1~11.9% (11.5% in average) of the total nitrogen load Sihwa-ho.

Application of GeoWEPP to determine the annual average sediment yield of erosion control dams in Korea

  • Rhee, Hakjun;Seo, Junpyo
    • Korean Journal of Agricultural Science
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    • v.47 no.4
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    • pp.803-814
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    • 2020
  • Managing erosion control dams requires the annual average sediment yield to determine their storage capacity and time to full sediment-fill and dredging. The GeoWEPP (Geo-spatial interface for Water Erosion Prediction Project) model can predict the annual average sediment yield from various land uses and vegetation covers at a watershed scale. This study assessed the GeoWEPP to determine the annual average sediment yield for managing erosion control dams by applying it to five erosion control dams and comparing the results with field observations using ground-based LiDAR (light detection and ranging). The modeling results showed some differences with the observed sediment yields. Therefore, GeoWEPP is not recommended to determine the annual average sediment yield for erosion control dams. Moreover, when using the GeoWEPP, the following is recommended :1) use the US WEPP climate files with similar latitude, elevation and precipitation modified with monthly average climate data in Korea and 2) use soil files based on forest soil maps in Korea. These methods resulted in GeoWEPP predictions and field observations of 0 and 63.3 Mg·yr-1 for the Gangneung, 142.3 and 331.2 Mg·yr-1 for the Bonghwa landslide, 102.0 and 107.8 Mg·yr-1 for the Bonghwa control, 294.7 and 115.0 Mg·yr-1 for the Chilgok forest fire, and 0 and 15.0 Mg·yr-1 for the Chilgok control watersheds. Application of the GeoWEPP in Korea requires 1) building a climate database fit for the WEPP using the meteorological data from Korea and 2) performing further studies on soil and streamside erosion to determine accurate parameter values for Korea.

Privacy-Preserving Estimation of Users' Density Distribution in Location-based Services through Geo-indistinguishability

  • Song, Seung Min;Kim, Jong Wook
    • Journal of the Korea Society of Computer and Information
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    • v.27 no.12
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    • pp.161-169
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    • 2022
  • With the development of mobile devices and global positioning systems, various location-based services can be utilized, which collects user's location information and provides services based on it. In this process, there is a risk of personal sensitive information being exposed to the outside, and thus Geo-indistinguishability (Geo-Ind), which protect location privacy of LBS users by perturbing their true location, is widely used. However, owing to the data perturbation mechanism of Geo-Ind, it is hard to accurately obtain the density distribution of LBS users from the collection of perturbed location data. Thus, in this paper, we aim to develop a novel method which enables to effectively compute the user density distribution from perturbed location dataset collected under Geo-Ind. In particular, the proposed method leverages Expectation-Maximization(EM) algorithm to precisely estimate the density disribution of LBS users from perturbed location dataset. Experimental results on real world datasets show that our proposed method achieves significantly better performance than a baseline approach.

Conceptual Design Analysis of Satellite Communication System for KASS (KASS 위성통신시스템 개념설계 분석)

  • Sin, Cheon Sig;You, Moonhee;Hyoung, Chang-Hee;Lee, Sanguk
    • Journal of Advanced Navigation Technology
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    • v.20 no.1
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    • pp.8-14
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    • 2016
  • High-level conceptual design analysis results of satellite communication system for Korea augmentation satellite system (KASS) satellite communication system, which is a part of KASS and consisted of KASS uplink Stations and two leased GEO is presented in this paper. We present major functions such as receiving correction and integrity message from central processing system, taking forward error correction for the message, modulating and up converting signal and conceptual design analysis for concepts for design process, GEO precise orbit determination for GEO ranging that is additional function, and clock steering for synchronization of clocks between GEO and GPS satellites. In addition to these, KASS requires 2.2 MHz for SBAS Augmentation service and 18.5 MHz for Geo-ranging service as minimum bandwidths as a results of service performance analysis of GEO ranging with respect to navigation payload(transponder) RF bandwidth is presented. These analysis results will be fed into KASS communication system design by carrying out final analysis after determining two GEOs and sites of KASS uplink stations.

Current Status of Geo-referenced Contents and a New Street Level Contents (공간정보 콘텐츠의 현황 및 새로운 거리 수준 콘텐츠)

  • Yoon, Bo Ram;Choi, Kyoung Ah;Lee, Im Pyeong
    • Spatial Information Research
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    • v.22 no.6
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    • pp.91-103
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    • 2014
  • The high popularity of geo-referenced mash-up improves the quality and availability of geo-referenced contents. Such contents which accurately represent the real world in street level as well as in aerial level have appeared. Despite the advent of geo-referenced contents of street level, it is still hardly used for mash-up. In this study, we thus find out its obstacles to spatial mash-up and solutions to overcome them to activate the mash-up based on street level contents. By analyzing the current geo-referenced content with respect to its spatial scope and the way of representation, we draw the limitations of current street level contents. Furthermore, we propose the 'new media geo-referenced content' as a solution to overcome those limitations. With 'new media geo-referenced content', it is able to determine the 3D coordinates of given object in real world. Using those coordinates, database linkage can be more closer, flexible and organic. Such 'new media geo-referenced content' can contribute to activation of geo-referenced contents in street level and its mash-up.

Bias Compensation of IKONOS Geo Imagery (IKONOS Geo Imagery의 편의 보정)

  • 김원만;김성삼;유환희
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2004.04a
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    • pp.197-202
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    • 2004
  • Recent researches have shown that IKONOS Geo imagery is capable of pixel-level geopositioning accuracy. However, a large number of ground control points(GCPs) are required in this case. For reducing the number of GCPs, users try to use the vender-supplied RPCs with Geo imagery. But, the biases included in RPCs give rise to absolute positioning error of about 25m as well known. In this paper, a method for the compensation of biases in rational polynomial coefficients(RPCs) for IKONOS Geo imagery is developed. the method requires provision of one or two GCPs to generate the compensated RPCs, and the analysis result of practical testing represents two or three pixels accuracy from IKONOS Geo imagery in case of using only compensated RPCs without GCPs.

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Enhancement of Geo-pointing Performance for Electro-Optical Systems by Compensating Transmission Time Delay of Navigation Data (항법정보 전송지연 보상을 통한 전자광학장비 좌표지향성능 향상)

  • Kim, Sung-Su;Moon, Seong-Man;Kwon, Kang-Hun;Yun, Chang-Ryul
    • Journal of the Korea Institute of Military Science and Technology
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    • v.16 no.2
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    • pp.191-198
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    • 2013
  • Geo-pointing is a function that maintains LOS(Line of Sight) to a stationary ground target by controlling azimuth and elevation angles of a EOS(Electro-Optical System) which are calculated from aircraft navigation data and target coordinates. In design and implementation of the geo-pointing, a transmission time delay between GPS/INS and EOS is a major degradation factor of the geo-pointing performance when the aircraft is rapidly maneuvered especially. In this paper, a kalman filter is designed to compensate the transmission time delay of aircraft navigation data. Simulation and test results show that the geo-pointing performance is enhanced by the proposed compensation technique.

Development of a Geo-Pointing System of Helicopter-Mounted FLIR (헬기 장착 전방관측적외선장비 좌표지향시스템 개발)

  • Kim, Sung-Su;Shin, Yong-San;Kim, Sung-Soo;Kwon, Kang-Hun
    • Journal of the Korea Institute of Military Science and Technology
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    • v.12 no.6
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    • pp.750-759
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    • 2009
  • FLIR(Forward Looking Infrared) geo-pointing is a function that helps pilots to see a target within the field of view under all coordinates and attitudes of helicopter. Geo-pointing controls FLIR LOS(line of sight) toward known target coordinates by using azimuth and elevation angles calculated from several information such as helicopter coordinates and attitudes, a FLIR position from a GPS antenna, and target coordinates. Geo-pointing performance has been tested and evaluated on the ground to save flight test costs and ensure flight safety. In this paper, design and implementation of a geo-pointing system is described with the results of performance test conducted on the ground test system.