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71.
All pairs (G,H) of graphs G,H satisfying L(G) = T(H) are determined. The “graph equation“ is also solved. 相似文献
72.
An Evolution Program for Non-Linear Transportation Problems 总被引:1,自引:0,他引:1
In this paper we describe main features of a Strongly Feasible Evolution Program (SFEP) designed to solve non-linear network flow problems. The program can handle non-linearities both in the constraints and in the objective function. The solutions procedure is based on a recombination operator in which all parents in a small mating pool have equal chance of contributing their genetic material to offspring. When offspring is created with better fitness value than that of the worst parent, the worst parent is discarded from the mating pool while the offspring is placed in it. The main contributions are in the massive parallel initialization procedure which creates only feasible solutions with simple heuristic rules that increase chances of creating solutions with good fitness values for the initial mating pool, and the gene therapy procedure which fixes defective genes ensuring that the offspring resulting from recombination is always feasible. Both procedures utilize the properties of network flows. The algorithm is capable of handling mixed integer problems with non-linearities in both constraints and the objective function. Tests were conducted on a number of previously published transportation problems with 49 and 100 decision variables, which constitute a subset of network flow problems. Convergence to equal or better solutions was achieved with often less than one tenth of the previous computational efforts. 相似文献
73.
Cuk T Baumberger F Lu DH Ingle N Zhou XJ Eisaki H Kaneko N Hussain Z Devereaux TP Nagaosa N Shen ZX 《Physical review letters》2004,93(11):117003
Angle-resolved photoemission spectroscopy on optimally doped Bi(2)Sr(2)Ca(0.92)Y(0.08)Cu(2)O(8+delta) uncovers a coupling of the electronic bands to a 40 meV mode in an extended k-space region away from the nodal direction, leading to a new interpretation of the strong renormalization of the electronic structure seen in Bi2212. Phenomenological agreements with neutron and Raman experiments suggest that this mode is the B(1g) oxygen bond-buckling phonon. A theoretical calculation based on this assignment reproduces the electronic renormalization seen in the data. 相似文献
74.
We explore manifestations of electron-phonon coupling on the electron spectral function for two phonon modes in the cuprates exhibiting strong renormalizations with temperature and doping. Applying simple symmetry considerations and kinematic constraints, we find that the out-of-plane, out-of-phase O buckling mode (B(1g)) involves small momentum transfers and couples strongly to electronic states near the antinode while the in-plane Cu-O breathing modes involve large momentum transfers and couples strongly to nodal electronic states. Band renormalization effects are found to be strongest in the superconducting state near the antinode, in full agreement with angle-resolved photoemission spectroscopy data. 相似文献
75.
The basic concepts of classical mechanics are given in operator form. Then ahybrid systems approach with the operator formulation of both quantum andclassical sectors is applied to the case of an ideal nonselective measurement. Itis found that the dynamical equation, consisting of the Schrödinger and Liouvilledynamics, produces noncausal evolution when the initial state of the measured(quantum mechanical) system and measuring apparatus=nclassical mechanicalsystem is chosen to be as demanded in discussions regarding the problem ofmeasurement. Nonuniqueness of possible realizations of the transition from apure noncorrelated to a mixed correlated state is analyzed in detail. It is concludedthat the state of the quantum mechanical system instantaneously collapses becauseof the nonnegativity of probabilities, and a dynamical model of this reductionis proposed. 相似文献
76.
Nonlinear Dynamics - In the present work, we deal with nonlinear dynamics of microtubules. A new model, describing nonlinear dynamics of microtubules, is introduced. Its advantages over two... 相似文献
77.
Slobodan Brinić Marijo Buzuk Marija Bralić Eni Generalić 《Journal of Solid State Electrochemistry》2012,16(4):1333-1341
The development of Cu(II) solid-contact ion-selective electrodes, based on 1,2-di-(o-salicylaldiminophenylthio)ethane as a neutral carrier, is presented. For the electrodes construction, unmodified carbon ink
(type 1 electrode) and polymer membrane-modified carbon ink (type 2 electrode) were used as solid support and transducer layer.
Also, carbon ink composite polymer membrane electrode (type 3 electrode) was prepared. The analytical performance of the electrodes
was evaluated with potentiometry, while bulk and interfacial electrode features were provided with electrochemical impedance
spectroscopy. It is shown that modification of carbon ink with polymer membrane cocktail decreases the bulk contact resistance
of the transducer layer and polymer membrane, thus enhancing the analytical performance of the electrode in terms of sensitivity,
linear range, and stability of potential. The optimized electrodes of types 2 and 3 exhibit a wide linear range with detection
limits of 1.8 × 10−6 and 1.6 × 10−6 M, respectively. They are suitable for determination of Cu2+ in analytical measurements by direct potentiometry and in potentiometric titrations, within pH between 2.3 and 6.5. The electrodes
are selective for Cu2+ over a large number of tested transition and heavy metal ions. 相似文献
78.
Rabaeh Khalid A. Hammoudeh Issra’ M. E. Moftah Belal Oglat Ammar A. Eyadeh Molham M. Aldweri Feras M. Abdel-Qader Ala’ J. Devic Slobodan 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(2):665-672
Journal of Radioanalytical and Nuclear Chemistry - A novel low toxic normoxic polymer gel dosimeter containing acrylic acid monomer is prepared and characterized for dosimetry in radiotherapy. Gel... 相似文献
79.
Employment of Jacobian elliptic functions for solving problems in nonlinear dynamics of microtubules
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Slobodan Zekovi Annamalai Muniyappan Slobodan Zdravkovi Louis Kavitha 《中国物理 B》2014,23(2):20504-020504
We show how Jacobian elliptic functions (JEFs) can be used to solve ordinary differential equations (ODEs) describing the nonlinear dynamics of microtubules (MTs). We demonstrate that only one of the JEFs can be used while the remaining two do not represent the solutions of the crucial differential equation. We show that a kinkbtype soliton moves along MTs. Besides this solution, we also discuss a few more solutions that may or may not have physical meanings. Finally, we show what kind of ODE can be solved by using JEFs. 相似文献
80.
In analysis of numerically simulated or experimentally obtained nematic textures, data visualisation plays an important role in interpretation and comparison of results. We review both commonly used, and more recently developed visual presentation methods that expose different aspects of the textures, from director field patterns and topological content of nematic defects, to deformation modes and simulated optical effects. We outline the theoretical background and potential uses, with examples that highlight the features of each of the described techniques. 相似文献