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131.
A stationary state of maximal entropy is derived as a solution of a variational procedure. Generators of a continuous group are used as the constraints. The self-consistent hamiltonian is linear in these generators so that the solution of the self-consistency problem is replaced by a solution of an algebraic equation. The familiar Hartree-Fock procedure is a special case. 相似文献
132.
The dynamic behaviour of the probe molecules DPH and TMA-DPH embedded in small unilamellar vesicles and planar multibilayers of POPC has been studied by time-resolved fluorescence depolarization techniques. The molecular dynamics of the probe molecules was analysed in terms of the rotational diffusion model. It is found that analysis of the time-dependent fluorescence anisotropy from the vesicle system yields two distinct, though statistically equivalent solutions. On the other hand the measurements on planar multibilayers can be interpreted unequivocally. It is shown that the order parameters of the probe molecules are higher in the multibilayers than in the vesicles. A reconstruction of the orientational distribution function reveals that the TMA-DPH molecules have a more pronounced tendency to lie with their long axes parallel to the bilayer surface in the curved vesicles than in the planar multibilayers. An intriguing finding is that the reorientational motion of the probes is considerably slower in the multibilayer samples than in the vesicles. These differences are attributed to the curvature and higher hydration of the bilayers in the vesicle systems. 相似文献
133.
134.
Abbott T Akiba Y Beavis D Bloomer MA Bond PD Chasman C Chen Z Chu YY Cole BA Costales JB Crawford HJ Cumming JB Debbe R Engelage J Fung SY Grodzins L Gushue S Hamagaki H Hansen O Hayano RS Hayashi S Homma S Huang HZ Ikeda Y Juricic I Kang J Katcoff S Kaufman S Kimura K Kitamura K Kurita K Ledoux RJ Levine MJ Miake Y Morse RJ Moskowitz B Nagamiya S Olness J Parsons CG Remsberg LP Sakurai H Sarabura M Shor A Stankus P Steadman SG Stephans GS Sugitate T Tanaka M Tannenbaum MJ Torikoshi M 《Physical review letters》1991,66(12):1567-1570
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Marc Levine 《K-Theory》1992,6(2):113-175
LetR be a commutative, semi-local ring,I
1, ...,I
s
ideals. In this paper, we define therelative Milnor K-groups of (R;I
1, ...,I
s
),K
p
M
(R;I
1, ...,I
s
), and show that these groups have many of the properties of the usual MilnorK-groups of a field. In particular, assuming a weak condition on the ideals, we show thatK
p
M
(R;I
1, ...,I
s
) is isomorphic to the weightp portion of the relative QuillenK-groupK
p
(R;I
1, ...,I
s
), after inverting (p–1)!. We also define the relative group homology of GL
n
(R;I
1, ...,I
s
), and show thatK
p
M
(R;I
1, ...,I
s
) is isomorphic toH
p
(GLp(R;I
1, ...,I
s
))/Im(H
p
(GL
p–1 (R;I
1, ...,I
s
))). Finally, we consider a generalization to the relative setting of Kato's conjecture asserting that the Galois symbol gives an isomorphism fromK
p
M
(F)/l
v
to
, and show that this relative version of Kato's conjecture implies the Quillen-Lichtenbaum conjectures asserting the Chern class:
相似文献
139.
140.
Estimates and regularization for solutions of some ill-posed problems of elliptic and parabolic type
In this paper, we examine, in a systematic fashion, some ill-posed problems arising in the theory of heat conduction. In abstract terms, letH be a Hilbert space andA: D (A)?H→H be an unbounded normal operator, we consider the boundary value problemü(t)=Au(t), 0<t<∞,u(0)=u 0∈D(A), \(\mathop {\lim }\limits_{t \to 0} \left\| {u\left( t \right)} \right\| = 0\) . The problem of recoveringu 0 whenu(T) is known for someT>0 is not well-posed. Suppose we are given approximationsx 1,x 2,…,x N tou(T 1),…,u(T N) with 0<T, <…<T N and positive weightsP i,i=1,…,n, \(\sum\limits_{i = 1}^N {P_i = 1} \) such that \(Q_2 \left( {u_0 } \right) = \sum\limits_{i = 1}^N {P_i } \left\| {u\left( {T_i } \right) - x_i } \right\|^2 \leqslant \varepsilon ^2 \) . If ‖u t(0)‖≤E for some a priori constantE, we construct a regularized solution ν(t) such that \(Q\left( {\nu \left( 0 \right)} \right) \leqslant \varepsilon ^2 \) while \(\left\| {u\left( 0 \right) - \nu \left( 0 \right)} \right\| = 0\left( {ln \left( {E/\varepsilon } \right)} \right)^{ - 1} \) and \(\left\| {u\left( t \right) - \nu \left( t \right)} \right\| = 0\left( {\varepsilon ^{\beta \left( t \right)} } \right)\) where 0<β(t)<1 and the constant in the order symbol depends uponE. The function β(t) is larger thant/m whent
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