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271.
In this paper, stability of a parametric quasivariational inequality of the Minty type is studied via various sufficient conditions characterizing upper and lower semicontinuity of the solution sets as well as the approximate solution sets. Sufficient conditions ensuring upper semicontinuity of the approximate solution sets of an optimization problem with quasivariational inequality constraints are also presented. 相似文献
272.
Iosif Pinelis 《Journal of Theoretical Probability》2011,24(2):409-421
Integral expressions for positive-part moments E X+pmathsf{E},X_{+}^{p} (p>0) of random variables X are presented, in terms of the Fourier–Laplace or Fourier transforms of the distribution of X. A necessary and sufficient condition for the validity of such an expression is given. This study was motivated by extremal problems in probability and statistics, where one needs to evaluate such positive-part moments. 相似文献
273.
Khakim D. Ikramov 《Computational Mathematics and Mathematical Physics》2011,51(4):505-512
Suppose that one should verify whether a given complex n × n matrix can be converted into a real matrix by a unitary similarity transformation. Sufficient conditions for this property
to hold were found in an earlier publication of this author. These conditions are relaxed in the following way: as before,
the spectrum is required to be simple, but pairs of complex conjugate eigenvalues $
\lambda ,\bar \lambda
$
\lambda ,\bar \lambda
are now allowed. However, the eigenvectors corresponding to such eigenvalues must not be orthogonal. 相似文献
274.
As evidence for his conjecture in birational log geometry, Kawamata constructed a family of derived equivalences between toric
orbifolds. In a previous paper, the authors showed that the derived category of a toric orbifold is naturally identified with
a category of polyhedrally-constructible sheaves on ℝ
n
. In this paper we investigate and reprove some of Kawamata’s results from this perspective. 相似文献
275.
Vitaly Maiorov 《Advances in Computational Mathematics》2010,32(2):239-253
We study geometrical properties of the ridge function manifold \(\mathcal{R}_n\) consisting of all possible linear combinations of n functions of the form g(a· x), where a·x is the inner product in \({\mathbb R}^d\). We obtain an estimate for the ε-entropy numbers in terms of smaller ε-covering numbers of the compact class G n,s formed by the intersection of the class \(\mathcal{R}_n\) with the unit ball \(B\mathcal{P}_s^d\) in the space of polynomials on \({\mathbb R}^d\) of degree s. In particular we show that for n?≤?s d???1 the ε-entropy number H ε (G n,s,L q ) of the class G n,s in the space L q is of order nslog1/ε (modulo a logarithmic factor). Note that the ε-entropy number \(H_\varepsilon(B\mathcal{P}_s^d,L_q)\) of the unit ball is of order s d log1/ε. Moreover, we obtain an estimate for the pseudo-dimension of the ridge function class G n,s. 相似文献
276.
K Sheibani 《The Journal of the Operational Research Society》2010,61(5):813-818
This paper describes a polynomial-time heuristic for the permutation flow-shop scheduling problem with the makespan criterion. The proposed method consists of two phases: arranging the jobs in priority order and then constructing a sequence. A fuzzy greedy evaluation function is employed to prioritize the jobs for incorporating into the construction phase of the heuristic. Computational experiments using standard benchmark problems indicate an improvement of the new heuristic over the well-known Nawaz, Enscore and Ham (NEH) heuristic. It will be seen that the NEH heuristic is a special case of our more general heuristic. 相似文献
277.
Lawrence W. Jones 《Czechoslovak Journal of Physics》2006,56(1):A201-A210
The L3 detector at the CERN electron-positron collider had a muon spectrometer which was employed during the last years of LEP operation for cosmic ray studies. The results of this program include a precise muon spectrum and charge ratio between 20 GeV and 3 TeV, a limit on TeV primary antiprotons from a study of the Moon’s shadow, the (possible) observation of a are signal from a fixed position in the northern hemisphere through muons, a solar anisotropy of 200 GeV protons, and other results. Negative limits on muons associated with known H.E. gamma sources or gamma bursts, the search for anomalous H.E. interaction or decay events such as reported from the Kolar Gold Fields, and a search for muons correlated with a solar are are also noted. 相似文献
278.
G. S. Khadekar B. Sarada Cenap Ozel 《International Journal of Theoretical Physics》2008,47(6):1542-1551
A homogeneous and isotropic Friedmann-Robertson-Walker (FRW) model with varying gravitational and cosmological constant is
studied in the context of higher dimensional space time. Exact solution of the field equations are obtained by using the “gamma
law” equation of state p=(γ−1)ρ, where γ is adiabatic parameter varies continuously as the universe expands. The functional form γ which is assumed to be the function of scale factor R as proposed by Carvalho (1996) is used to analyse the behavior of scale factor R, cosmological constant Λ and the gravitational constant G for two different phases: inflation and radiation. The various physical aspects of the early cosmological models has also
been discussed in the framework of higher dimensional space time. 相似文献
279.
Xiaoying Yang Zhuohan Zhang Zunfeng Liu Yanfeng Ma Rongcun Yang Yongsheng Chen 《Journal of nanoparticle research》2008,10(5):815-822
Multi-functionalized single walled carbon nanotubes (SWNTs) were prepared and applied as tumor cell targeting biological transporters.
A positive charge was introduced on SWNTs to get high loading efficiency of fluorescein (FAM) labeled short double strands
DNA (20 base pairs). The SWNTs were encapsulated with the folic acid modified phospholipids for active targeting into tumor
cell. The tumor cell-targeting properties of these multi-functionalized SWNTs were investigated by active targeting into mouse
ovarian surface epithelial cells. The experimental results show that these multi-functionalized SWNTs have good tumor cell
targeting property. 相似文献
280.
We constrain the possible time variation of the Higgs vacuum expectation value (v) by recent results on the primordial 4He abundance (Y
P
). For that, we use an analytic approach which enables us to take important issues into consideration, that have been ignored
by previous works, like the v-dependence of the relevant cross sections of deuterium production and photodisintegration, including the full Klein–Nishina
cross section. Furthermore, we take a non-equilibrium Ansatz for the freeze-out concentration of neutrons and protons and
incorporate the latest results on the neutron decay. Finally, we approximate the key-parameters of the primordial 4He production (the mean lifetime of the free neutron and the binding energy of the deuteron) by terms of
(where v
0 denotes the present theoretical estimate). Eventually, we derive the relation
and the most stringent limit on a possible time variation of v is given by:
. 相似文献