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111.
Nguyen V. Thoai 《Journal of Global Optimization》2000,18(4):321-336
The problem of optimizing some contiuous function over the efficient set of a multiple objective programming problem can be formulated as a nonconvex global optimization problem with special structure. Based on the conical branch and bound algorithm in global optimization, we establish an algorithm for optimizing over efficient sets and discuss about the implementation of this algorithm for some interesting special cases including the case of biobjective programming problems. 相似文献
112.
Alain Escassut Ta Thi Hoai An 《P-Adic Numbers, Ultrametric Analysis, and Applications》2018,10(1):12-31
Let IK be an algebraically closed field of characteristic 0 complete for an ultrametric absolute value. Following results obtained in complex analysis, here we examine problems of uniqueness for meromorphic functions having finitely many poles, sharing points or a pair of sets (C.M. or I.M.) defined either in the whole field IK or in an open disk, or in the complement of an open disk. Following previous works in C, we consider functions fn(x)fm(ax + b), gn(x)gm(ax + b) with |a| = 1 and n ≠ m, sharing a rational function and we show that f/g is a n + m-th root of 1 whenever n + m ≥ 5. Next, given a small function w, if n, m ∈ IN are such that |n ? m|∞ ≥ 5, then fn(x)fm(ax + b) ? w has infinitely many zeros. Finally, we examine branched values for meromorphic functions fn(x)fm(ax + b). 相似文献
113.
We obtain global bounds in Lorentz–Morrey spaces for gradients of solutions to a class of quasilinear elliptic equations with low integrability data. The results are then applied to obtain sharp existence results in the framework of Morrey spaces for Riccati type equations with a gradient source term having growths below the natural exponent of the operator involved. A special feature of our results is that they hold under a very general assumption on the nonlinear structure, and under a mild natural restriction on the boundary of the ground domain. 相似文献
114.
Quoc Thong Nguyen Kim Phuc Tran Henri L. Heuchenne Thi Hien Nguyen Huu Du Nguyen 《商业与工业应用随机模型》2019,35(5):1253-1268
In many industrial manufacturing processes, the ratio of the variance to the mean of a quantity of interest is an important characteristic to ensure the quality of the processes. This ratio is called the coefficient of variation (CV). A lot of control charts have been designed for monitoring the CV of univariate quantity in the literature. However, the CV control charts for multivariate quantity have not received much attention yet. In this paper, we investigate a variable sampling interval (VSI) Shewhart control chart for monitoring multivariate CV. The time between two consecutive samples is allowed to vary according to the previous value of the multivariate CV, which will help the chart to detect the process shifts faster. The comparison with the fixed sampling interval Shewhart chart is implemented to highlight the advantage of the VSI method. Finally, an illustrative example is demonstrated on real data. 相似文献
115.
Q.-Y. Shao A.-D. Li J.-B. Cheng H.-Q. Ling D. Wu Z.-G. Liu N.-B. Ming C. Wang H.-W. Zhou B.-Y. Nguyen 《Applied Physics A: Materials Science & Processing》2005,81(6):1181-1185
LaAlO3 (LAO) gate dielectric films were deposited on Si substrates by low-pressure metalorganic chemical vapor deposition. The interfacial structure and composition distribution were investigated by high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), secondary-ion mass spectroscopy (SIMS), and Auger-electron spectroscopy (AES). HRTEM confirms that there exists an interfacial layer between LAO and Si in most samples. AES, SIMS, and XPS analyses indicate that the interfacial layer is compositionally graded La–Al silicate and the Al element is severely deficient close to the Si surface. Electrical properties of LAO films were evaluated. No evident difference in electrical properties between samples with and without native SiO2 layers was observed. The electrical properties are discussed in terms of LAO growth mechanisms, in relation to the interfacial structure. PACS 73.40.Qv; 81.15.Gh; 77.55.+f; 68.35.-p 相似文献
116.
Nguyen Van Ho 《Applications of Mathematics》1998,43(2):93-102
Let X
i, 1 i N, be N independent random variables (i.r.v.) with distribution functions (d.f.) F
i(x,), 1 i N, respectively, where is a real parameter. Assume furthermore that F
i(·,0) = F(·) for 1 i N.
Let R = (R
1,R
N) and R
+,...,R
N
+
be the rank vectors of X = (X
1,X
N) and |X|=(|X
1|,...,|X
N|), respectively, and let V = (V
1,V
N) be the sign vector of X. The locally most powerful rank tests (LMPRT) S = S(R) and the locally most powerful signed rank tests (LMPSRT) S = S(R
+, V) will be found for testing = 0 against > 0 or < 0 with F being arbitrary and with F symmetric, respectively. 相似文献
117.
This paper gives lower estimates for the frequency modules of almost periodic solutions to equations of the form
, where A generates a strongly continuous semigroup in a Banach space
, F(t,x) is 2π-periodic in t and continuous in (t,x), and f is almost periodic. We show that the frequency module ℳ(u) of any almost periodic mild solution u of (*) and the frequency module ℳ(f) of f satisfy the estimate e
2π
iℳ(f)⊂e
2π
iℳ(u). If F is independent of t, then the estimate can be improved: ℳ(f)⊂ℳ(u). Applications to the nonexistence of quasi-periodic solutions are also given. 相似文献
118.
We define a generalized mass for asymptotically flat manifolds using some higher order symmetric function of the curvature tensor. This mass is non-negative when the manifold is locally conformally flat and the σ k curvature vanishes at infinity. In addition, with the above assumptions, if the mass is zero, then, near infinity, the manifold is isometric to a Euclidean end. 相似文献
119.
Using variational methods, we prove the existence of a nontrivial weak solution for the problem
{-∑i=1^Nδxi(|δxiu|pi-2δxiu)=λα(x)|u|q(x)-2u+|u|p*-2u,in Ω,
u=0 inδΩ,
where Ω R^N(N≥3) is a bounded domain with smooth boundary δΩ,2≤pi〈N,i=1,N,q:Ω→(1,p*)is a continuous function, p* =N/∑i=1^N 1/pi-1 is the critical exponent for this class of problem, and λ is a parameter. 相似文献
{-∑i=1^Nδxi(|δxiu|pi-2δxiu)=λα(x)|u|q(x)-2u+|u|p*-2u,in Ω,
u=0 inδΩ,
where Ω R^N(N≥3) is a bounded domain with smooth boundary δΩ,2≤pi〈N,i=1,N,q:Ω→(1,p*)is a continuous function, p* =N/∑i=1^N 1/pi-1 is the critical exponent for this class of problem, and λ is a parameter. 相似文献
120.
The observation of isolated positive and negative charges, but not isolated magnetic north and south poles, is an old puzzle. Instead, evidence of effective magnetic monopoles has been found in the abstract momentum space. Apart from Hall-related effects, few observable consequences of these abstract monopoles are known. Here, we show that it is possible to manipulate the monopoles by external magnetic fields and probe them by universal conductance fluctuation measurements in ferromagnets with strong spin-orbit coupling. The observed fluctuations are not noise, but reproducible quasiperiodic oscillations as a function of magnetization direction, a novel Berry phase fingerprint of the magnetic monopoles. 相似文献