• Title/Summary/Keyword: Space group

Search Result 3,027, Processing Time 0.026 seconds

CME and radio characteristics of making large solar proton events

  • Hwang, Jung-A;Cho, Kyung-Suk;Bong, Su-Chan;Kim, Su-Jin;Park, Young-Deuk
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.35 no.1
    • /
    • pp.33.2-33.2
    • /
    • 2010
  • We have investigated a relationship among the solar proton events (SPEs), coronal mass ejections (CMEs) and solar flares during the solar cycle 23 (1997-2006). Using 63 SPE dataset, we found that SPE rise time, duration time, and decrease times depend on CME speed and SPE peak intensity depends on the CME earthward direction parameter as well as CME speed and x-ray flare intensity. While inspecting the relation between SPE peak intensity and the CME earthward direction parameter, we found that there are two groups: first group consists of large 6 SPEs (> 10,000 pfu at >10 MeV proton channel of GOES satellite) and shows a very good correlation (cc=0.65) between SPE peak intensity and CME earthward direction parameter. The second group has a relatively weak SPE peak intensity and shows poor correlation between SPE peak intensity and the CME earthward direction parameter (cc=0.01). By investigating characteristics of 6 SPEs in the first group, we found that there are special common conditions of the extremely large proton events (group 1); (1) all the SPEs are associated with very fast halo CME (>1400km/s), (2) they are almost located at disk region, (3) they also accompany large flare (>M7), (4) all they are preceded by another wide CMEs, and (5) they all show helmet streamer nearby the main CME. In this presentation, we will give details of the energy spectra of the 6 SPE events from the ERNE/HED aboard the Solar and Heliospheric Observatory (SOHO), and onset time comparison among the SPE, flare, type II burst, and CME.

  • PDF

IMAGING OBSERVATION SYSTEM USING CMOS IMAGE SENSOR (CMOS 영상센서를 이용한 영상관측장비 활용)

  • Jin, Ho;Park, Young-Sik;Park, Jang-Hyun;Yuk, In-Soo;Seon, Kwang-Il;Nam, Wook-Won;Han, Won-Yong;Lee, Woo-Baik;Lee, Sung-Woon;Shin, Young-Hoon
    • Journal of Astronomy and Space Sciences
    • /
    • v.18 no.3
    • /
    • pp.231-238
    • /
    • 2001
  • A prototype CMOS (complementary metal oxide semiconductor) imaging system has been built and the possibility of applying to the application to astronomical observations has been investigated. The CCD (charge coupled device) image sensor has been the mainstay of image capture and astronomical imaging for the last 30 years, but CMOS devices have shown rapidly increasing success and have been adapted to many commercial imaging systems . Although the photometric performances and system noise of CMOS sensors are lower than that of CCD image sensors, CMOS Imaging system can be used to obtain general image capture for astronomical applications.

  • PDF

DIMENSIONAL STABILITY OF IMPRESSION BODY USING SILICONE INDEX TOOTH TRAY IMPRESSION SYSTEM (Silicone Index Tooth Tray를 이용한 인상체의 체적안정성에 대한 연구)

  • Lee Kyu-Young;Jeong Seung-Mi;Shim June-Sung;Choi Byung-Gap;Lee Keun-Woo
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.43 no.5
    • /
    • pp.622-632
    • /
    • 2005
  • Statement of problem: Silicone Index Tooth Tray impression system which does not use gingicord has a shortcoming. It takes time to remove internal wall of Silicone Index Tooth Tray for space of wash impression material. Purpose: This study was to evaluate whether providing certain space to impression body can prevent from doing complicated laboratory work. Material and methods: After mounting metal dies with shoulder and chamfer margins arbiturarily, SITT was produced using $Blu-mousse^(R)$. In one experimental group, wash impression was taken using $Fit-tester^(R)$ without removing interior surface of SITT and in the other group, wash impression was taken using $Fit-tester^(R)$ providing 0.5mm space in the SITT and then compared the differences in two groups. Results: 1. There was no significant difference between a group which did not allow space and a group which granted equal 0.5mm space. 2. There was no significant difference between gingival diameter, occlusal diameter of metal die that has shoulder margin and gingival diameter, occlusal diameter of metal die that has chamfer margin. 3. There was no significant difference between a group which did not take pick-up impression and a group which took pick-up impression through relining method using SITT 4. There was no significant difference between a group that poured immediately after taking primary impression and a group that poured after removing poured stone die. Conclusions: When taking an impression of an abutment using SITT impression system, it is considered to obtain clinically identical results between a group that did not grant a 0.5mm space within SITT for wash impression and a group which invest a space. Furthermore, it is considered possible to produce an individual die through secondary pouring.

The Behavior of Space Occupancy as Demonstrated caused by Activities of Daily Living of Residents in Group Homes for Elderly People (고령자 그룹홈 거주자의 일상생활능력에 따른 공간이용행태)

  • Kim, Hyun-Jin;Lim, Hi-Kyung;An, Ok-Hee
    • Journal of the Korean Home Economics Association
    • /
    • v.44 no.7 s.221
    • /
    • pp.177-188
    • /
    • 2006
  • This study evaluated 26 elderly residents living independently in 4 group homes for their abilities in daily living and analyzed their behaviors of space occupancy and activities of daily living. The aim of the study was to identify the relationships between the physical environments of the group homes and the daily activities of the residents. The results of this study are summarized as follows. 1) Most residents in the group home considered bathing and cooking to be the most difficult of their living activities. The residents were categorized into "Independent," "Semi-dependent" and "Dependent" groups, on the basis of their ADL and IADL scores, and individual groups were examined. On ADL scorelt was shown, then, that 65.4% of the residents were was independent in ADL, but there was no any significant difference in IADL between the independent, semi-dependent and dependent groups. In addition, there was a difference in ADL and IADL among the groups. The independent group's residents were shown to be independent in ADL and IADL, whereas the but those of the semi-dependent and dependent groups' residents were lower in IADL than in ADL. 2) When their behaviors of space occupancy were examined, it appeared that the independent group showed a different space sharing pattern among individual residents, with a wide range of behavior of space occupancy. Meanwhile, The semi-dependent group mostly shared a common space with simple activities of daily living while no any service low leisure program was provided. However, the dependent group mainly consisted of residents who had a low level of independence in ADL and IADL, so that their behaviors of space occupancy were entirely negative.

INVARIANT RINGS AND DUAL REPRESENTATIONS OF DIHEDRAL GROUPS

  • Ishiguro, Kenshi
    • Journal of the Korean Mathematical Society
    • /
    • v.47 no.2
    • /
    • pp.299-309
    • /
    • 2010
  • The Weyl group of a compact connected Lie group is a reflection group. If such Lie groups are locally isomorphic, the representations of the Weyl groups are rationally equivalent. They need not however be equivalent as integral representations. Turning to the invariant theory, the rational cohomology of a classifying space is a ring of invariants, which is a polynomial ring. In the modular case, we will ask if rings of invariants are polynomial algebras, and if each of them can be realized as the mod p cohomology of a space, particularly for dihedral groups.