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161.
Radu Ioan Bo? Sorin-Mihai Grad 《Journal of Mathematical Analysis and Applications》2008,337(2):1315-1325
We give some necessary and sufficient conditions which completely characterize the strong and total Lagrange duality, respectively, for convex optimization problems in separated locally convex spaces. We also prove similar statements for the problems obtained by perturbing the objective functions of the primal problems by arbitrary linear functionals. In the particular case when we deal with convex optimization problems having infinitely many convex inequalities as constraints the conditions we work with turn into the so-called Farkas-Minkowski and locally Farkas-Minkowski conditions for systems of convex inequalities, recently used in the literature. Moreover, we show that our new results extend some existing ones in the literature. 相似文献
162.
近来,一种称之为时标动力系统的新理论得到了蓬勃的发展. 该文给出并建立了时标动力系统的各种稳定性概念和Lyapunov稳定性准则(稳定, 一致稳定, 渐近稳定, 指数渐近稳定等等). 相似文献
163.
The condensation of benzene 1,3,5-tricarbonylchloride with cystine-di-Me [H2N-CH(COOMe)-CH2-S-S-CH2-CH(COOMe)-NH2] yielded triply bridged (1,3,5) cyclophane 1, which was shown by detailed spectral studies and molecular orbital calculations to have a D3 symmetry with conformationally identical linkers and a spherical topology. In sharp contrast, the (1,3,5) cyclophane 2 from the rarely studied lanthionine di-Me [H2N-CH(COOMe)-CH2-S-CH2-CH(COOMe)-NH2], showed only a equatorial twofold symmetry. This work highlights the special properties of the -S-S- bridge in cystine, which makes it an exceptional synthon in nature and organic synthesis. 相似文献
164.
Ahmad Shaabani Ali Hossein Rezayan Afshin Sarvary Sajjad Keshipour Hamid Reza Khavasi 《Tetrahedron letters》2010,51(31):4091-3424
An unexpected coupling reaction between isocyanides and carboxylic acids which led to the synthesis of highly stable symmetrical and unsymmetrical alkylamidine and arylamidine carbocations under mild reaction conditions is described. The structures of these compounds were confirmed by IR, mass, 1H NMR, 13C NMR, and single-crystal X-ray diffraction studies and a plausible mechanism is proposed. 相似文献
165.
Zhiliang Xu Yingjie Liu Huijing Du Guang Lin Chi-Wang Shu 《Journal of computational physics》2011,230(17):6843-6865
We develop a new hierarchical reconstruction (HR) method and for limiting solutions of the discontinuous Galerkin and finite volume methods up to fourth order of accuracy without local characteristic decomposition for solving hyperbolic nonlinear conservation laws on triangular meshes. The new HR utilizes a set of point values when evaluating polynomials and remainders on neighboring cells, extending the technique introduced in Hu, Li and Tang [9]. The point-wise HR simplifies the implementation of the previous HR method which requires integration over neighboring cells and makes HR easier to extend to arbitrary meshes. We prove that the new point-wise HR method keeps the order of accuracy of the approximation polynomials. Numerical computations for scalar and system of nonlinear hyperbolic equations are performed on two-dimensional triangular meshes. We demonstrate that the new hierarchical reconstruction generates essentially non-oscillatory solutions for schemes up to fourth order on triangular meshes. 相似文献
166.
Simone Göttlich Simon Hoher Patrick Schindler Veronika Schleper Alexander Verl 《Applied Mathematical Modelling》2014
In this paper a model comparison approach based on material flow systems is investigated that is divided into a microscopic and a macroscopic model scale. On the microscopic model scale particles are simulated using a model based on Newton dynamics borrowed from the engineering literature. Phenomenological observations lead to a hyperbolic partial differential equation on the macroscopic model scale. Suitable numerical algorithms are presented and both models are compared numerically and validated against real-data test settings. 相似文献
167.
168.
In the present paper the author investigates the global structure stability of Riemann solutions for general quasilinear hyperbolic systems of conservation laws under small BV perturbations of the initial data, where the Riemann solution contains rarefaction waves, while the perturbations are in BV but they are assumed to be C1-smooth, with bounded and possibly large C1-norms. Combining the techniques employed by Li–Kong with the modified Glimm’s functional, the author obtains a lower bound of the lifespan of the piecewise C1 solution to a class of generalized Riemann problems, which can be regarded as a small BV perturbation of the corresponding Riemann problem. This result is also applied to the system of traffic flow on a road network using the Aw–Rascle model. 相似文献
169.
演化博弈理论解决策略均衡问题是目前比较认可的好方法.对于博弈方的经验行为,还未曾研究.本文以非对称2×2的博弈问题为研究对象,建立起带有时滞的博弈系统,通过动力学相关知识,分别研究了两类系统下博弈参与者策略的稳定状态.数值模拟分析了延时给决策带来的影响.实验表明,时滞作用不改变策略的稳定状态,改变的仅是达到稳态的速率. 相似文献
170.
《Communications in Nonlinear Science & Numerical Simulation》2014,19(7):2228-2233
By solving the zero-curvature equation associated with a 3 × 3 matrix spectral problem, a super hierarchy of coupled derivative nonlinear Schrödinger equations is proposed. The corresponding super bi-Hamiltonian structures are established by means of the super trace identity. Then, we derive infinite conservation laws of the super coupled derivative nonlinear Schrödinger equation with the aid of spectral parameter expansions. 相似文献