• Title/Summary/Keyword: Density 전파

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A study of Establishment on Radiomap that Utilizes the Mobile device Indoor Positioning DB based on Wi-Fi (Wi-Fi 기반 모바일 디바이스 실내측위 DB를 활용한 라디오맵 구축에 관한 연구)

  • Jeong, In Hun;Kim, Chong Mun;Choi, Yun Soo;Kim, Sang Bong;Lee, Yun
    • Journal of Korean Society for Geospatial Information Science
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    • v.22 no.3
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    • pp.57-69
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    • 2014
  • As of 2013, Korean population density is 505 persons per $1km^2$ and is ranked 3rd place in the most densely populated countries exception of city-states. It shows clearly the population is concentrated in the city area. To fulfil this urban concentration population demand, the enlargement and complexation of buildings, subway and other underground spaces connection tendency has been intensified, and it is need to construct the indoor spatial information DB as well as the accurate indoor surveying DB to promote people's safety and social welfare. In this study, Sadang station and Incheon National Airport were aimed for the construction of Wi-Fi AP location DB and RadioMap DB by collecting the indoor AP raw datas by using mobile device and those collected results were ran through the process of verification, supplementation, and analyzation. To evaluate the performance of constructed DB, 10 points in Incheon Airport- 3rd flr in block A, and 9 points in Sadang station-B1 were selected and calculated the estimated points and ran evaluation experiment using survey positioning error, which is distance between real position and the estimated position. The result shows that Incheon international airport's average and standard deviation was separately 17.81m, 17.79m and Sadang station's average and standard deviation was separately 22.64m, 23.74m. In Sadang station's case, the areas near the exit has low performance of surveying position due to fewer visible AP points than other areas. As total datas were examined except those position, it was verified that the user's location was mapping close position in surveying positioning by using constructed DB. It means that constructed DB contains correct Wi-Fi AP locations and radio wave patterns in object region, so it is considered that the indoor spatial information service based on constructed DB would be available.

Thrips Infesting Hot Pepper Cultured in Greenhouses and Variation in Gene Sequences Encoded in TSWV (시설재배지 고추를 가해하는 총채벌레류와 TSWV 유전자 서열 변이)

  • Kim, Chulyoung;Choi, Duyeol;Kang, Jeong Hun;Ahmed, Shabbir;Kil, Eui-Joon;Kwon, Gimyeon;Lee, Gwan-Seok;Kim, Yonggyun
    • Korean journal of applied entomology
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    • v.60 no.4
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    • pp.387-401
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    • 2021
  • Thrips infesting hot peppers were monitored in greenhouses using yellow sticky traps. In addition, the hot peppers infected with tomato spotted wilt virus (TSWV) were observed during the monitoring period. The flower thrips (Frankliniella intonsa) were initially trapped at a low density just after transplanting seedlings of hot peppers at late March. The western flower thrips (Frankliniella occidentalis) were trapped after mid April. These two thrips represented more than 98% of the total thrips attracted to the traps after May, in which F. intonsa showed higher occurrence frequency than F. occidentalis. The total number of thrips had two peaks at mid May with a small and short-term peak and at June-July with a large and long-term peak. The trapped thrips exhibited inconsistent sex ratios, suggesting a seasonal parthenogenesis. Different geographical populations were varied in cytochrome oxidase I sequences, in which local populations in Andong shared a high sequence similarity. TSWV-infected hot peppers, which might be mediated by these two thrips species, were observed and confirmed by an immunoassay kit and a molecular diagnosis using RT-PCR. In addition, the TSWV was detected in F. occidentalis collected from the infected hot peppers. Three open reading frames (NSS, N, and NSM) of the isolated TSWV genomes were sequenced and showed multiple point mutations containing missense mutations among geographical variants. When the isolated TSWV was fed to nonvirulent thrips of F. occidentalis, the virus was detected in both larvae and adults. However, the viral replication occurred in larvae, but not in adults.