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101.
102.
Andrea Caliciotti Giovanni Fasano Stephen G. Nash Massimo Roma 《Operations Research Letters》2018,46(1):7-12
Starting from the paper by Nash and Sofer (1990), we propose a heuristic adaptive truncation criterion for the inner iterations within linesearch-based truncated Newton methods. Our aim is to possibly avoid “over-solving” of the Newton equation, based on a comparison between the predicted reduction of the objective function and the actual reduction obtained. A numerical experience on unconstrained optimization problems highlights a satisfactory effectiveness and robustness of the adaptive criterion proposed, when a residual-based truncation criterion is selected. 相似文献
103.
《组合设计杂志》2018,26(7):344-355
We derive a previously unknown lower bound of 41 for the frequency of of an E(s2)‐optimal and minimax‐optimal supersaturated design (SSD) with 20 rows and 76 columns. This is accomplished by an exhaustive computer search that uses the combinatorial properties of resolvable 2 − (20, 10, 36) designs and the parallel class intersection pattern method. We also classify all nonisomorphic E(s2)‐optimal 4‐circulant SSDs with 20 rows and . 相似文献
104.
建立灵敏、可靠的中药材中农药多残留的检测方法对保证中药材的质量和安全十分重要.制备了磁性亲水亲脂平衡萃取材料Fe3 O4@PLS,将其应用于农药多残留的磁性基质固相分散萃取中,并结合高效液相色谱-串联质谱法(HPLC-MS/MS)检测了金银花、菊花和三七块根(干)3种中药材中76种农药残留量.研究通过扫描电子显微镜(S... 相似文献
105.
This paper focuses on the class of finite-state, discrete-index, reciprocal processes (reciprocal chains). Such a class of processes seems to be a suitable setup in many applications and, in particular, it appears well-suited for image-processing. While addressing this issue, the aim is 2-fold: theoretic and practical. As to the theoretic purpose, some new results are provided: first, a general stochastic realization result is provided for reciprocal chains endowed with a known, arbitrary, distribution. Such a model has the form of a fixed-degree, nearest-neighbour polynomial model. Next, the polynomial model is shown to be exactly linearizable, which means it is equivalent to a nearest-neighbour linear model in a different set of variables. The latter model turns out to be formally identical to the Levi–Frezza–Krener linear model of a Gaussian reciprocal process, although actually non-linear with respect to the chain's values. As far as the practical purpose is concerned, in order to yield an example of application an estimation issue is addressed: a suboptimal (polynomial-optimal) solution is derived for the smoothing problem of a reciprocal chain partially observed under non-Gaussian noise. To this purpose, two kinds of boundary conditions (Dirichlet and Cyclic), specifying the reciprocal chain on a finite interval, are considered, and in both cases the model is shown to be well-posed, in a ‘wide-sense’. Under this view, some well-known representation results about Gaussian reciprocal processes extend, in a sense, to a ‘non-Gaussian’ case. 相似文献
106.
Huang Zhaoyong 《代数通讯》2013,41(12):5791-5812
Let λ be an artin algebra and λω λ a faithfully balanced self-orthogonal bimodule. We generalize the notion of the Auslander-Bridger transpose to that of the transpose with respect to λω λand obtain some properties about dual modules with respect toλω λFurther, we characterize cotilting bimodules and give criteria for computing generalized Goren-stein dimension. 相似文献
107.
The indentation-derived elastic modulus, E, of bovine compact bone was obtained by nanoindentation. The indentation modulus of the dry condition (i.e. under atmospheric conditions) is 40% higher than when measured wet (i.e. immersed in buffer solution). Although this difference is independent of orientation, there is a 20% difference in the indentation modulus within the same tested environment between longitudinal and transversal directions. In addition, the estimated indentation modulus of the same samples when tested wet in buffer solution after deep freezing (?15°C) was not affected. The discrepancy between wet and dry results was attributed to the non-mineralized phase contribution and rationalized by a simple mechanical model [I. Jäger and P. Fratzl, Biophys. J. 79 (2000) p.1737]. Anisotropy effects could be explained in terms of deformation mechanisms with orientation. The effect of frozen storage temperatures may be clarified considering the biomechanics of the helicoidal arrangement of lamellar bone. Viscoelastic effects were also considered and incorporated into analysis of the force–displacement data. 相似文献
108.
《Journal of Nonlinear Mathematical Physics》2013,20(1):151-160
This paper studies structures of the 3-Lie algebra M realized by the general linear Lie algebra gl(n, ?). We show that M has only one nonzero proper ideal. We then give explicit expressions of both derivations and inner derivations of M. Finally, we investigate substructures of the (inner) derivation algebra of M. 相似文献
109.
Ansgar Jüngel René Pinnau Elisa Röhrig 《Mathematical Methods in the Applied Sciences》2013,36(13):1701-1712
A simplified transient energy‐transport system for semiconductors subject to mixed Dirichlet–Neumann boundary conditions is analyzed. The model is formally derived from the non‐isothermal hydrodynamic equations in a particular vanishing momentum relaxation limit. It consists of a drift‐diffusion‐type equation for the electron density, involving temperature gradients, a nonlinear heat equation for the electron temperature, and the Poisson equation for the electric potential. The global‐in‐time existence of bounded weak solutions is proved. The proof is based on the Stampacchia truncation method and a careful use of the temperature equation. Under some regularity assumptions on the gradients of the variables, the uniqueness of solutions is shown. Finally, numerical simulations for a ballistic diode in one space dimension illustrate the behavior of the solutions. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
110.
Ayumu Hoshino 《代数通讯》2013,41(6):1997-2018
We describe the crystal bases of the modified quantum algebras and give the explicit form of the highest (or lowest) weight vector of its connected component B 0(λ) containing the unit element for arbitrary rank 2 cases. We also present the explicit form of B 0(λ) containing the highest (or lowest) weight vector by the polyhedral realization method. 相似文献