• Title/Summary/Keyword: partial stability

Search Result 530, Processing Time 0.025 seconds

STABILITY OF THE $\bar\partial$-ESTIMATES AND THE MERGELYAN PROPERTY FOR WEAKLY q-CONVEX MANIFOLDS

  • Seo, Yeon-Seok
    • East Asian mathematical journal
    • /
    • v.24 no.3
    • /
    • pp.263-274
    • /
    • 2008
  • Let $r\;{\geq}\;q$. We get the stability of the estimates of the $\bar{\partial}$-Neumann problem for (p, r)-forms on a weakly q-convex complex submanifold. As a by-product of the stability of the $\bar{\partial}$-estimates, we get the Mergelyan approximation property for (p, r)-forms on a weakly q-convex complex submanifold which satisfies property (P).

  • PDF

STABILITY IN THE α-NORM FOR SOME STOCHASTIC PARTIAL FUNCTIONAL INTEGRODIFFERENTIAL EQUATIONS

  • Diop, Mamadou Abdoul;Ezzinbi, Khalil;Lo, Modou
    • Journal of the Korean Mathematical Society
    • /
    • v.56 no.1
    • /
    • pp.149-167
    • /
    • 2019
  • In this work, we study the existence, uniqueness and stability in the ${\alpha}$-norm of solutions for some stochastic partial functional integrodifferential equations. We suppose that the linear part has an analytic resolvent operator in the sense given in Grimmer [8] and the nonlinear part satisfies a $H{\ddot{o}}lder$ type condition with respect to the ${\alpha}$-norm associated to the linear part. Firstly, we study the existence of the mild solutions. Secondly, we study the exponential stability in pth moment (p > 2). Our results are illustrated by an example. This work extends many previous results on stochastic partial functional differential equations.

EXISTENCE, UNIQUENESS AND STABILITY OF IMPULSIVE STOCHASTIC PARTIAL NEUTRAL FUNCTIONAL DIFFERENTIAL EQUATIONS WITH INFINITE DELAYS

  • Anguraj, A.;Vinodkumar, A.
    • Journal of applied mathematics & informatics
    • /
    • v.28 no.3_4
    • /
    • pp.739-751
    • /
    • 2010
  • This article presents the result on existence, uniqueness and stability of mild solution of impulsive stochastic partial neutral functional differential equations under sufficient condition. The results are obtained by using the method of successive approximation.

Thermal Stability of Superconductor NdBCO Sintered at Various Oxygen Partial Pressures (다양한 산소분압에서 소결한 NdBCO 초전도체의 열적 안정성)

  • Chung, J.K.;Kim, W.J.;Park, S.C.;Kang, S.G.;Lim, Y.J.;Kim, C.J.
    • Progress in Superconductivity
    • /
    • v.10 no.2
    • /
    • pp.133-138
    • /
    • 2009
  • The $Nd_{1+x}Ba_{2-x}Cu_3O_{7-{\delta}}$(Nd123) superconductor exhibits high performance in high magnetic field and high temperature. We have studied phase stability for Nd123 under reduced oxygen partial pressure and various heat-treatment conditions. The main phase is Nd123 and some samples contain small amounts of Nd422 depending on the temperature and oxygen partial pressure. The decomposition temperature decreases with decreasing oxygen partial pressure from $1052^{\circ}C(P(O_2)$=150 Torr) to about $845^{\circ}C(P(O_2)$=0.1 Torr). The liquidus line was steeper temperature with decreasing oxygen partial pressure. In same condition of oxygen partial pressure, the region of stable Nd123 phase was formed at slightly higher temperature than the region of stable YBCO phase.

  • PDF

Dynamic Stability of a Cantilevered Timoshenko Beam on Partial Elastic Foundations Subjected to a Follower Force

  • Ryu, Bong-Jo;Shin, Kwang-Bok;Yim, Kyung-Bin;Yoon, Young-Sik
    • Journal of Mechanical Science and Technology
    • /
    • v.20 no.9
    • /
    • pp.1355-1360
    • /
    • 2006
  • This paper presents the dynamic stability of a cantilevered Timoshenko beam with a concentrated mass, partially attached to elastic foundations, and subjected to a follower force. Governing equations are derived from the extended Hamilton's principle, and FEM is applied to solve the discretized equation. The influence of some parameters such as the elastic foundation parameter, the positions of partial elastic foundations, shear deformations, the rotary inertia of the beam, and the mass and the rotary inertia of the concentrated mass on the critical flutter load is investigated. Finally, the optimal attachment ratio of partial elastic foundation that maximizes the critical flutter load is presented.

Influence of Partial Elastic Foundations on Dynamic Stability of a Cantilevered Timoshenko Beam with a Tip Mass under a follower force (끝단 질량을 갖고 종동력을 받는 외팔 Timoshenko 보의 동적안정성에 미치는 부분 탄성기초의 영향)

  • Shin, Kwang-Bok;Kim, Hyo-Jun;Ryu, Bong-Jo
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.22 no.10 s.175
    • /
    • pp.65-71
    • /
    • 2005
  • This paper presents the dynamic stability of a cantilevered Timoshenko beam on partial elastic foundations subjected to a follower force. The beam with a tip concentrated mass is assumed to be a Timoshenko beam taking into account its rotary inertia and shear deformation. Governing equations are derived by extended Hamilton's principle, and finite element method is applied to solve the discretized equation. Critical follower force depending on the attachment ratios of partial elastic foundations, rotary inertia of the beam and magnitude and rotary inertia of the tip mass is fully investigated.

Effect of a Partial Elastic Foundation on Dynamic Stability of a Cantilevered Timoshenko Beam under a Follower Force (종동력을 받는 외팔 Timoshenko보의 동적안정성에 미치는 부분탄성기초의 영향)

  • Ryu, Bong-Jo;Ryu, Si-Ung;Han, Hyun-Hee;Kim, Hyo-Jun
    • Proceedings of the KSME Conference
    • /
    • 2004.04a
    • /
    • pp.911-916
    • /
    • 2004
  • The paper deals with the dynamic stability of a cantilevered Timoshenko beam on partial elastic foundations subjected to a follower force. The beam is assumed to be a Timoshenko beam with a concentrated mass taking into account its rotary inertia and shear deformation. Governing equations are derived by extended Hamilton's principle, and FEM is applied to solve the discretized equation. Critical follower force depending on the attachment ratios of partial elastic foundations, concentrated mass and rotary inertia of the beam is fully investigated.

  • PDF

Partial Purification and Stability of a Water-soluble Yellow Pigment from Bacillus sp. PY123. (Bacillus sp. PY123 균주가 생성하는 수용성 황색수소의 부분 정제 및 그 안정성)

  • 김지연;김광현;김병우;이광배
    • Journal of environmental and Sanitary engineering
    • /
    • v.14 no.4
    • /
    • pp.35-40
    • /
    • 1999
  • For application of a yellow pigment as food additives, stability of a water-soluble yellow pigment from Bacillus sp. PY123 was investigated. The yellow pigment from Bacillus sp. PY123 was purified with pH treatment, activated carbon and silica gel column chromatography. The partial purified yellow pigment appeared only one spot on silica gel TLC after 12 evaporation and under irradiation of UV 253nm at dark room. Rf value of the pigment was measured at 0.04 and 0.12 with development of a solvent mixture (Butanol : Acetic acid : water = 4 :1:5) and a solvent mixture (Isopropanol : Ammonia : Water = 9 :1: 2), respectively, The partial purified pigment appeared a white fluorescence under UV365nm irradiation. The partial purified yellow pigment had a main peak and a minor peak on HPLC using 20mM phosphate buffer(pH 7.0) at 1ml/min flow rate. The partial purified pigment was stable at heat treatment, acidic pH, oxide-reductants and surfactants.

  • PDF