• Title/Summary/Keyword: Replica

Search Result 512, Processing Time 0.033 seconds

Relocation Strategy for an Efficient Management of Replicated Data on Mobile Computing (모바일 컴퓨팅상에서 중복데이터의 효율적 관리를 위한 재배치 전략)

  • Lee, Byung-Kwan;Oh, Am-Suk;Jeong, Eun-Hee
    • Journal of Korea Multimedia Society
    • /
    • v.7 no.5
    • /
    • pp.689-697
    • /
    • 2004
  • Rapid advances in mobile computing and the availability of wireless communications will soon provide mobile users with the ability to access data regardless of the location of the user or of the data. SRA(Static Replica Allocation) that is traditional scheme has been used for the replication method on the server. This replicates the data on the replica server after a moving host has been transferred to the cell. This strategy is simple and can easily relocate data. However, if a mobile user does not exist in the cell, the replicated data can be deleted in order to maintain data consistency. In addition to, if the mobile host leaves from replicated cell, it is difficult to access data in terms of replication route. Therefore, this paper proposes a new method of relocation based on data consistency strategy called USRAC(User Selection Replica Allocation based on Consistency) and also analyzes access cost according to the moving rate of mobile users, according to the access rate of mobile hosts, and according to the number of cells of mobile users and mobile hosts.

  • PDF

Vibrational Modes of Pyeongeong (편경의 진동모드 분석)

  • Yoo June-Hee
    • The Journal of the Acoustical Society of Korea
    • /
    • v.25 no.3
    • /
    • pp.121-128
    • /
    • 2006
  • Korean pyeongyeong, a set of sixteen L-shape chime stones covering one and one third octaves, is a standard instrument in the Korean traditional court music. We analyze the vibrational mode frequencies in a pyeongyeong replica which is played at the National Center for Korean Traditional Performance Arts and pyeongyeong remains which are exhibited at King Sejong Memorial Museum. The modal shapes on the Whangjong, the 1st stone and Cheonghyurjong, the 16th stone mapped by scanning accelerometer, TV holography and STAR system. The nominal frequencies in pyeongyeong replica at the National Center for Korean Traditional Performance Arts increase linearly with the thickness of the stones and the tones are tuned in line with the musical scale of Sambunsonik. The sexagenary cycles on the pyeongyeong remains at King Sejong Memorial. which show the Year of product indirectly, are different each other and the tones are not tuned in scale. The relative frequency ratios of each modes on stones differ more than just-noticeable differences from those on the pyeongyeong replica. Modal shapes are same for the two stones regardless of the thickness.

Changes of Facial Wrinkle after Topical Application of On Emulsion Containing Medimin A (Medimin A를 함유한 O/W 에멀전의 주름 개선 효과)

  • 박선규;장민열;김영득;정봉열;원영호;김진준;강세훈
    • Journal of the Society of Cosmetic Scientists of Korea
    • /
    • v.25 no.1
    • /
    • pp.23-36
    • /
    • 1999
  • Medimin A is a derivative of vitamin A which has been developed by coupling retinoic acid with polyethylene glycol(PEG) to enhance skin permeability and stability. We carried out the collagen synthesis and clinical test to examine the reducing effect of wrinkles by Medimin A. In vitro collagen synthesis was evaluated by quantitative assay of ($^3$H)-proline incorporation into collagenase sensitive protein in fibroblast cultures. Clinical test was evaluated by image analysis of skin replica, visual observation and self-estimated response of volunteers for 10 weeks. Medimin A stimulated about 40% in collagen synthesis. The area of main deep wrinkle on the skin replica was reduced 38.4% with topical application of O/W emulsion containing 0.2% Medimin A. The wrinkles on the eye region was also reduced 25.4%-44.1% by the visual observation and 93% of all volunteers responded that topical application of the O/W emulsion was showed some reducing effect of wrinkles after 10 weeks. From these results, we suggest that Medimin A is a potent anti-wrinkle agent by objective evaluation methods(in vitro collagen synthesis and image analysis of skin replica) and subjective evaluation methods(visual observation and self-estimated response of volunteers).

  • PDF

법랑질 평골면 갈색반의 형태학적 관찰

  • Min, Sung-Kee
    • The Journal of the Korean dental association
    • /
    • v.12 no.10
    • /
    • pp.763-766
    • /
    • 1974
  • The electron microscopic observation on the browny discolored enamel spot on smooth surface of permanent teeth was performed by mean of the Filmy Replica method and obtained the following: 1) The browny discolored enamel spot on smooth surface of permanenet teeth was identified as a dental caries.

  • PDF

Nondestructive Creep Damage Evaluation of High-Temperature Pipelines by Ultrasonic Attenuation Measurement and Electric Resistance Methods (초음파 감쇠 및 전기저항 측정법에 의한 발전소 고온배관의 크리프손상 평가)

  • Lee, In-Cheol;Kil, Du-Song;Gung, Gye-Jo;Cho, Yong-Sang;Lee, Sang-Guk
    • Journal of Ocean Engineering and Technology
    • /
    • v.13 no.3 s.33
    • /
    • pp.100-107
    • /
    • 1999
  • Due to the high temperature and pressure, the materials of pipeline in power plant are degraded by creep damage. So far, many conventional measurement techniques such as replica method, electric resistance method, adn hardness test method for creep damage have been used. Among them, the replica method has mainly been used for the inspection of components. But this technique is restricted to the applications at the surface of the objects and cannot be used to material inside. In this paper, the measuring methods of evaluation by using ultrasonic attenuation and electric resistance for the creep detection of creep damage in the form of cavities on grain boundaries or intergranular microcracks were carried out. Absolute measuring method of quantitave ultrasonic attenuation technique for 1Cr0.5Mo material degradation was analyzed for determining the creep degradation steps using life prediction formula. As a result of measurement for creep specimens, we founded that the coefficient of utrasonic attenuation was increased as the increase of creep life fracton(${phi}c$) and the decreasing rate of wlwctric resistance was also increased.

  • PDF

Creep Damage Evaluation of High-Temperature Pipeline in Power Plant by Using Ultrasonic Velocity Measurement and Hardness Test (초음파 음속 및 경도법에 의한 발전소 고온배관재의 크리프 손상평가)

  • Hur, Kwang-Beom;Yoo, Keun-Bong;Cho, Yong-Sang;Lee, Sang-Guk
    • Journal of Ocean Engineering and Technology
    • /
    • v.13 no.3 s.33
    • /
    • pp.92-99
    • /
    • 1999
  • High temperature and pressure materials in power plant are degraded by creep damage, if they are exposed to constant loads for long times, which occurs in load bearing structures of pressurized components operationg at elevated temperatures. Many conventional measurement techniques such as replica method, electric resistance method, and hardness test method for measuring creep damgage have been used. So far, the replica method is mainly used for the inspection of high temperature and pressure components. This technique is, however, restricted to applications at the surface of the testpieces and cannot be used to material inside. In this paper, ultrasonic evaluation for the detection of creep damage in the form of cavaties on grain boundaries or intergranular microcracks were carried out. And the absolute measuring method of quantitative ultrasonic velocity technique for Cr-Mo material degradation was analyzed. As a result of ultrasonic tests for crept for specimens, we founded that the sound velocity was decreased as increase of creep life fraction(${phi}c$) and also, confirmed that hardness was decreased as increase of creep life fraction(${phi}c$).

  • PDF