• 제목/요약/키워드: IPS g-value

검색결과 5건 처리시간 0.018초

Development of Forecast Algorithm for Coronal Mass Ejection Speed and Arrival Time Based on Propagation Tracking by Interplanetary Scintillation g-Value

  • Park, Sa-Rah;Jeon, Ho-Cheol;Kim, Rok-soon;Kim, Jong-Hyeon;Kim, Seung-Jin;Cho, Junghee;Jang, Soojeong
    • Journal of Astronomy and Space Sciences
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    • 제37권1호
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    • pp.43-50
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    • 2020
  • We have developed an algorithm for tracking coronal mass ejection (CME) propagation that allows us to estimate CME speed and its arrival time at Earth. The algorithm may be used either to forecast the CME's arrival on the day of the forecast or to update the CME tracking information for the next day's forecast. In our case study, we successfully tracked CME propagation using the algorithm based on g-values of interplanetary scintillation (IPS) observation provided by the Institute for Space-Earth Environmental Research (ISEE). We were able to forecast the arrival time (Δt = 0.30 h) and speed (Δv = 20 km/s) of a CME event on October 2, 2000. From the CME-interplanetary CME (ICME) pairs provided by Cane & Richardson (2003), we selected 50 events to evaluate the algorithm's forecast capability. Average errors for arrival time and speed were 11.14 h and 310 km/s, respectively. Results demonstrated that g-values obtained continuously from any single station observation were able to be used as a proxy for CME speed. Therefore, our algorithm may give stable daily forecasts of CME position and speed during propagation in the region of 0.2-1 AU using the IPS g-values, even if IPS velocity observations are insufficient. We expect that this algorithm may be widely accepted for use in space weather forecasting in the near future.

Facilitators and Barriers in the Use of a Checklist by Insurance Physicians during Work Ability Assessments in Depressive Disorder

  • Blok, Sebastiaan;Gouttebarge, Vincent;Slebus, Frans G.;Sluiter, Judith K.;Frings-Dresen, Monique H.W.
    • Safety and Health at Work
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    • 제2권4호
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    • pp.328-335
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    • 2011
  • Objectives: Depressive disorder (DD) is a complex disease, and the assessment of work ability in patients with DD is also complicated. The checklist depression (CDp) has recently been developed to support such work ability assessments and has been recommended for implementation in insurance medicine, starting with an analysis of the organisational and social contexts. The aim of this study was to identify the potential facilitators and barriers in the use of the CDp by insurance physicians (IPs) during work ability assessments of employees on sick leave due to DD. Methods: A qualitative research was conducted based on semi-structured interviews. The participants were IPs with at least one year of work experience in performing work ability assessments. The interviews were audiotaped, transcribed and analysed qualitatively. Results: Ten IPs (7 males, 3 females; mean 53 years) were interviewed. Important facilitators, which emerged for use of the CDp, were an oral introduction for colleagues and staff, support from management, valuing the increased transparency in work ability assessments with using the CDp, having adequate time for assessments as well as modification of the appearance (colour, plasticised form) and content (clarifying aspects of the examples) of the assessment tool. The fear of the loss of autonomy, lack of added value of the CDp, high workload, inadequate instructions and lack of time were mentioned as barriers. Conclusion: Adequate introduction to the use of CDp and the fear of the loss of autonomy of IPs need special attention in planning its implementation.

The improvement of GTG response time using new concept LC mixture in S-IPS Mode for high frame frequency technologies

  • Kim, D.K.;Lim, C.S.;Lee, D.J.;Hwang, J.I.;Jung, H.G.;Lee, S.W.;Oh, C.H.;Kang, I.B.;Jin, Min-Ok;Jin, Heui-Seok;Lee, Seung-Eun;Jacob, Thomas;Czanta, Markus;Tarumi, Kazuaki
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.864-867
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    • 2006
  • In order to satisfy with the clear visibility without any difficulties such as blurring and tailing, the high refreshing rate technology and fast response time of LC itself were applied to TFT-LCDs. In proportion to the decrease of holding time of 1 frame, the fast transition of LC behavior was necessary to both maintain the luminance and minimize the tailing appearance. The introduction of a new LC mixture for faster response times was realized by the good combination of newly introduced dielectrically neutral LC material so called 'Super Low Viscosity' (SLV) and highly polar $CF_2O-linkage$ LC material. This resulted in about a 20% reduction in the ${\gamma}_1$ of the new LC mixture compared to the references. In accordance with a new LC mixture with low ${\gamma}_1$, fast response time of 5ms has been made for S-IPS LCD TV application. Consequently, by applying the high frame frequency of 120Hz driving alongside the 5ms response time characteristics, the MPRT value was reduced by half.

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슈퍼컴퓨터 보안 이슈 및 대책 (Supercomputer's Security Issues and Defense: Survey)

  • 홍성혁
    • 디지털융복합연구
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    • 제11권4호
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    • pp.215-220
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    • 2013
  • 슈퍼 컴퓨터는 20G 프리플롭을 처리 할 수 있는 용량을 가진 컴퓨터를 말하며, 과거에는 슈퍼 컴퓨터로 복잡한 과학 계산을 처리하였으며, 지금도 많은 클라이언트 컴퓨터가 복잡한 계산 처리를 요청하면 빠른 처리 속도로 클라이언트의 요청을 처리하고 있다. 슈퍼 컴퓨터가 바이러스에 감염될 경우 연결된 많은 클라이언트 컴퓨터에 영향을 미칠 수 있기 때문에 최근 사이버 공격은 슈퍼 컴퓨터에 초점을 맞추고 있고, 따라서, 본 연구 논문은 슈퍼 컴퓨터 보안 문제를 분석하고 슈퍼 컴퓨터의 보안 레벨을 올리기 위해 현재 문제점과 생체정보를 이용한 방어책을 제시하였다.

Enhanced Production of Valuable Bioactive Metabolites in Submerged Cultures of Medicinal Mushroom Ganoderma lucidum by Manipulation of Oxygen Supply

  • Zhong, Jian-Jiang;Fang, Qing-Hua;Tang, Ya-Jie
    • Journal of Plant Biotechnology
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    • 제4권3호
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    • pp.109-115
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    • 2002
  • Submerged cultures of Ganoderma lucidum, a valuable mushroom in traditional Chinese medicine, were used for production of bioactive Banoderic acids and Ganoderma polysaccharides. The significant effects of oxygen supply were demonstrated in both shake flasks and bioreactors. By changing the medium loading volume in a shake flask, a different value of initial volumetric oxygen transfer coefficient ($K_L$a) was obtained, and a higher $K_L$a value led to a higher biomass density and a higher productivity of both intracellular polysaccharide and ganoderic acid. In a stirred bioreactor, at an initial $K_L$a of 78.2 $h^{-1}$, a maximal cell concentration of 15.6 g/L by dry weight was obtained, as well as a maximal intracellular polysarcharide (IPS) production of 2.2 g/L and its maximal productivity of 220 mg/(L.d). An increase of initial $K_L$a led to a higher production and productivity of GA, and the GA production and productivity at an initial $K_L$a of 96.0 $h^{-1}$ was 1.8-fold those at an initial $K_L$a of 16.4 $h^{-1}$. The fundamental information obtained in this study may be useful for efficient large-scale production of these valuable bioactive products by the submerged cultures.